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Sample records for gene repertoires species-specific

  1. Identification of a bitter-taste receptor gene repertoire in different Lagomorphs species

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    Ana M. Ferreira

    2016-04-01

    Full Text Available The repertoires of bitter taste receptor (T2R gene have been described for several animal species, but these data are still scarce for Lagomorphs. The aim of the present work is to identify potential repertoires of T2R in several Lagomorph species, covering a wide geographical distribution. We studied these genes in Lepus timidus, Lepus europaeus, Oryctolagus cuniculus algirus, Romerolagus diazi and Sylvilagus floridanus, using Oryctolagus cuniculus cuniculus as control species for PCR and DNA sequencing. We studied the identities of the DNA sequences and built the corresponding phylogenetic tree. Sequencing was successful for both subspecies of Oryctolagus cuniculus for all T2R genes studied, for five genes in Lepus, and for three genes in Romerolagus diazi and Sylvilagus floridanus. We describe for the first time the partial repertoires of T2R genes for Lagomorphs species, other than the common rabbit. Our phylogenetic analyses indicate that sequence proximity levels follow the established taxonomic classification.

  2. Conserved repertoire of orthologous vomeronasal type 1 receptor genes in ruminant species

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    Okamura Hiroaki

    2009-09-01

    Full Text Available Abstract Background In mammals, pheromones play an important role in social and innate reproductive behavior within species. In rodents, vomeronasal receptor type 1 (V1R, which is specifically expressed in the vomeronasal organ, is thought to detect pheromones. The V1R gene repertoire differs dramatically between mammalian species, and the presence of species-specific V1R subfamilies in mouse and rat suggests that V1R plays a profound role in species-specific recognition of pheromones. In ruminants, however, the molecular mechanism(s for pheromone perception is not well understood. Interestingly, goat male pheromone, which can induce out-of-season ovulation in anestrous females, causes the same pheromone response in sheep, and vice versa, suggesting that there may be mechanisms for detecting "inter-species" pheromones among ruminant species. Results We isolated 23 goat and 21 sheep intact V1R genes based on sequence similarity with 32 cow V1R genes in the cow genome database. We found that all of the goat and sheep V1R genes have orthologs in their cross-species counterparts among these three ruminant species and that the sequence identity of V1R orthologous pairs among these ruminants is much higher than that of mouse-rat V1R orthologous pairs. Furthermore, all goat V1Rs examined thus far are expressed not only in the vomeronasal organ but also in the main olfactory epithelium. Conclusion Our results suggest that, compared with rodents, the repertoire of orthologous V1R genes is remarkably conserved among the ruminants cow, sheep and goat. We predict that these orthologous V1Rs can detect the same or closely related chemical compound(s within each orthologous set/pair. Furthermore, all identified goat V1Rs are expressed in the vomeronasal organ and the main olfactory epithelium, suggesting that V1R-mediated ligand information can be detected and processed by both the main and accessory olfactory systems. The fact that ruminant and rodent V1Rs

  3. Diversification of the Primary Antibody Repertoire by AID-Mediated Gene Conversion.

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    Lanning, Dennis K; Knight, Katherine L

    2015-01-01

    Gene conversion, mediated by activation-induced cytidine deaminase (AID), has been found to contribute to generation of the primary antibody repertoire in several vertebrate species. Generation of the primary antibody repertoire by gene conversion of immunoglobulin (Ig) genes occurs primarily in gut-associated lymphoid tissues (GALT) and is best described in chicken and rabbit. Here, we discuss current knowledge of the mechanism of gene conversion as well as the contribution of the microbiota in promoting gene conversion of Ig genes. Finally, we propose that the antibody diversification strategy used in GALT species, such as chicken and rabbit, is conserved in a subset of human and mouse B cells.

  4. Co-regulation of a large and rapidly evolving repertoire of odorant receptor genes

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    Lane Robert P

    2007-09-01

    Full Text Available Abstract The olfactory system meets niche- and species-specific demands by an accelerated evolution of its odorant receptor repertoires. In this review, we describe evolutionary processes that have shaped olfactory and vomeronasal receptor gene families in vertebrate genomes. We emphasize three important periods in the evolution of the olfactory system evident by comparative genomics: the adaptation to land in amphibian ancestors, the decline of olfaction in primates, and the delineation of putative pheromone receptors concurrent with rodent speciation. The rapid evolution of odorant receptor genes, the sheer size of the repertoire, as well as their wide distribution in the genome, presents a developmental challenge: how are these ever-changing odorant receptor repertoires coordinated within the olfactory system? A central organizing principle in olfaction is the specialization of sensory neurons resulting from each sensory neuron expressing only ~one odorant receptor allele. In this review, we also discuss this mutually exclusive expression of odorant receptor genes. We have considered several models to account for co-regulation of odorant receptor repertoires, as well as discussed a new hypothesis that invokes important epigenetic properties of the system.

  5. Evidence of strain structure in Plasmodium falciparum var gene repertoires in children from Gabon, West Africa.

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    Day, Karen P; Artzy-Randrup, Yael; Tiedje, Kathryn E; Rougeron, Virginie; Chen, Donald S; Rask, Thomas S; Rorick, Mary M; Migot-Nabias, Florence; Deloron, Philippe; Luty, Adrian J F; Pascual, Mercedes

    2017-05-16

    Existing theory on competition for hosts between pathogen strains has proposed that immune selection can lead to the maintenance of strain structure consisting of discrete, weakly overlapping antigenic repertoires. This prediction of strain theory has conceptual overlap with fundamental ideas in ecology on niche partitioning and limiting similarity between coexisting species in an ecosystem, which oppose the hypothesis of neutral coexistence. For Plasmodium falciparum , strain theory has been specifically proposed in relation to the major surface antigen of the blood stage, known as Pf EMP1 and encoded by the multicopy multigene family known as the var genes. Deep sampling of the DBLα domain of var genes in the local population of Bakoumba, West Africa, was completed to define whether patterns of repertoire overlap support a role of immune selection under the opposing force of high outcrossing, a characteristic of areas of intense malaria transmission. Using a 454 high-throughput sequencing protocol, we report extremely high diversity of the DBLα domain and a large parasite population with DBLα repertoires structured into nonrandom patterns of overlap. Such population structure, significant for the high diversity of var genes that compose it at a local level, supports the existence of "strains" characterized by distinct var gene repertoires. Nonneutral, frequency-dependent competition would be at play and could underlie these patterns. With a computational experiment that simulates an intervention similar to mass drug administration, we argue that the observed repertoire structure matters for the antigenic var diversity of the parasite population remaining after intervention.

  6. The repertoire of bitter taste receptor genes in canids.

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    Shang, Shuai; Wu, Xiaoyang; Chen, Jun; Zhang, Huanxin; Zhong, Huaming; Wei, Qinguo; Yan, Jiakuo; Li, Haotian; Liu, Guangshuai; Sha, Weilai; Zhang, Honghai

    2017-07-01

    Bitter taste receptors (Tas2rs) play important roles in mammalian defense mechanisms by helping animals detect and avoid toxins in food. Although Tas2r genes have been widely studied in several mammals, minimal research has been performed in canids. To analyze the genetic basis of Tas2r genes in canids, we first identified Tas2r genes in the wolf, maned wolf, red fox, corsac fox, Tibetan fox, fennec fox, dhole and African hunting dog. A total of 183 Tas2r genes, consisting of 118 intact genes, 6 partial genes and 59 pseudogenes, were detected. Differences in the pseudogenes were observed among nine canid species. For example, Tas2r4 was a pseudogene in the dog but might play a functional role in other canid species. The Tas2r42 and Tas2r10 genes were pseudogenes in the maned wolf and dhole, respectively, and the Tas2r5 and Tas2r34 genes were pseudogenes in the African hunting dog; however, these genes were intact genes in other canid species. The differences in Tas2r pseudogenes among canids might suggest that the loss of intact Tas2r genes in canid species is species-dependent. We further compared the 183 Tas2r genes identified in this study with Tas2r genes from ten additional carnivorous species to evaluate the potential influence of diet on the evolution of the Tas2r gene repertoire. Phylogenetic analysis revealed that most of the Tas2r genes from the 18 species intermingled across the tree, suggesting that Tas2r genes are conserved among carnivores. Within canids, we found that some Tas2r genes corresponded to the traditional taxonomic groupings, while some did not. PIC analysis showed that the number of Tas2r genes in carnivores exhibited no positive correlation with diet composition, which might be due to the limited number of carnivores included in our study.

  7. The normally expressed kappa immunoglobulin light chain gene repertoire and somatic mutations studied by single-sided specific polymerase chain reaction (PCR); frequent occurrence of features often assigned to autoimmunity

    DEFF Research Database (Denmark)

    Juul, L; Hougs, L; Andersen, V

    1997-01-01

    The expressed human kappa light chain gene repertoire utilized by healthy individuals was studied by two different single-sided specific PCR techniques to avoid bias for certain V genes. A total of 103 rearranged kappa sequences from peripheral blood mononuclear cells from healthy individuals were...

  8. Genome sequencing and comparative genomics reveal a repertoire of putative pathogenicity genes in chilli anthracnose fungus Colletotrichum truncatum.

    Science.gov (United States)

    Rao, Soumya; Nandineni, Madhusudan R

    2017-01-01

    Colletotrichum truncatum, a major fungal phytopathogen, causes the anthracnose disease on an economically important spice crop chilli (Capsicum annuum), resulting in huge economic losses in tropical and sub-tropical countries. It follows a subcuticular intramural infection strategy on chilli with a short, asymptomatic, endophytic phase, which contrasts with the intracellular hemibiotrophic lifestyle adopted by most of the Colletotrichum species. However, little is known about the molecular determinants and the mechanism of pathogenicity in this fungus. A high quality whole genome sequence and gene annotation based on transcriptome data of an Indian isolate of C. truncatum from chilli has been obtained. Analysis of the genome sequence revealed a rich repertoire of pathogenicity genes in C. truncatum encoding secreted proteins, effectors, plant cell wall degrading enzymes, secondary metabolism associated proteins, with potential roles in the host-specific infection strategy, placing it next only to the Fusarium species. The size of genome assembly, number of predicted genes and some of the functional categories were similar to other sequenced Colletotrichum species. The comparative genomic analyses with other species and related fungi identified some unique genes and certain highly expanded gene families of CAZymes, proteases and secondary metabolism associated genes in the genome of C. truncatum. The draft genome assembly and functional annotation of potential pathogenicity genes of C. truncatum provide an important genomic resource for understanding the biology and lifestyle of this important phytopathogen and will pave the way for designing efficient disease control regimens.

  9. A survey of the gene repertoire of Gigaspora rosea unravels conserved features among Glomeromycota for obligate biotrophy

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    Nianwu eTANG

    2016-03-01

    Full Text Available Arbuscular mycorrhizal (AM fungi are a diverse group of soil fungi (Glomeromycota that form the most ancient mutualistic association termed arbuscular mycorrhizal symbiosis with a majority of land plants, improving their nutrition uptake and resistance to stresses. In contrast to their great ecological implications, the knowledge of the molecular biological mechanisms involved is still scant, partly due to the limited genomic resources available. Here, we describe the gene repertoire of a new AM fungus Gigaspora rosea (Diversisporales. Among the 86332 nonredundant virtual transcripts assembled, 15346 presented similarities with proteins in the Refseq database and 10175 were assigned with GO terms. KOG and Interpro domain annotations clearly showed an enrichment of genes involved in signal transduction in G. rosea. KEGG pathway analysis indicates that most primary metabolic processes are active in G. rosea. However, as for R. irregularis, several metabolic genes were not found, including the fatty acid synthase gene. This finding supports the hypothesis that AM fungi depend on the lipids produced by their hosts. Furthermore, the presence of a large number of transporters and hundreds of secreted proteins, together with the reduced number of plant cell wall degrading enzymes could be interpreted as an evolutionary adaptation to its mutualistic obligate biotrophy. The detection of meiosis-related genes suggests that G. rosea might use a cryptic sexual process. Lastly, a phylogeny of basal fungi clearly shows Glomeromycota as a sister clade to Mucoromycotina, not only to the Mucorales or Mortierellales. The characterization of the gene repertoire from an AM fungal species belonging to the order of Diversisporales and its comparison with the gene sets of R. irregularis (Glomerales and Gigaspora margarita (Diversisporales, reveal that AM fungi share several features linked to mutualistic obligate biotrophy. This work contributes to lay the foundation

  10. Genomes of the most dangerous epidemic bacteria have a virulence repertoire characterized by fewer genes but more toxin-antitoxin modules.

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    Kalliopi Georgiades

    2011-03-01

    Full Text Available We conducted a comparative genomic study based on a neutral approach to identify genome specificities associated with the virulence capacity of pathogenic bacteria. We also determined whether virulence is dictated by rules, or if it is the result of individual evolutionary histories. We systematically compared the genomes of the 12 most dangerous pandemic bacteria for humans ("bad bugs" to their closest non-epidemic related species ("controls".We found several significantly different features in the "bad bugs", one of which was a smaller genome that likely resulted from a degraded recombination and repair system. The 10 Cluster of Orthologous Group (COG functional categories revealed a significantly smaller number of genes in the "bad bugs", which lacked mostly transcription, signal transduction mechanisms, cell motility, energy production and conversion, and metabolic and regulatory functions. A few genes were identified as virulence factors, including secretion system proteins. Five "bad bugs" showed a greater number of poly (A tails compared to the controls, whereas an elevated number of poly (A tails was found to be strongly correlated to a low GC% content. The "bad bugs" had fewer tandem repeat sequences compared to controls. Moreover, the results obtained from a principal component analysis (PCA showed that the "bad bugs" had surprisingly more toxin-antitoxin modules than did the controls.We conclude that pathogenic capacity is not the result of "virulence factors" but is the outcome of a virulent gene repertoire resulting from reduced genome repertoires. Toxin-antitoxin systems could participate in the virulence repertoire, but they may have developed independently of selfish evolution.

  11. Rapid evolution of the sequences and gene repertoires of secreted proteins in bacteria.

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    Teresa Nogueira

    Full Text Available Proteins secreted to the extracellular environment or to the periphery of the cell envelope, the secretome, play essential roles in foraging, antagonistic and mutualistic interactions. We hypothesize that arms races, genetic conflicts and varying selective pressures should lead to the rapid change of sequences and gene repertoires of the secretome. The analysis of 42 bacterial pan-genomes shows that secreted, and especially extracellular proteins, are predominantly encoded in the accessory genome, i.e. among genes not ubiquitous within the clade. Genes encoding outer membrane proteins might engage more frequently in intra-chromosomal gene conversion because they are more often in multi-genic families. The gene sequences encoding the secretome evolve faster than the rest of the genome and in particular at non-synonymous positions. Cell wall proteins in Firmicutes evolve particularly fast when compared with outer membrane proteins of Proteobacteria. Virulence factors are over-represented in the secretome, notably in outer membrane proteins, but cell localization explains more of the variance in substitution rates and gene repertoires than sequence homology to known virulence factors. Accordingly, the repertoires and sequences of the genes encoding the secretome change fast in the clades of obligatory and facultative pathogens and also in the clades of mutualists and free-living bacteria. Our study shows that cell localization shapes genome evolution. In agreement with our hypothesis, the repertoires and the sequences of genes encoding secreted proteins evolve fast. The particularly rapid change of extracellular proteins suggests that these public goods are key players in bacterial adaptation.

  12. Gain, loss and divergence in primate zinc-finger genes: a rich resource for evolution of gene regulatory differences between species.

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    Katja Nowick

    Full Text Available The molecular changes underlying major phenotypic differences between humans and other primates are not well understood, but alterations in gene regulation are likely to play a major role. Here we performed a thorough evolutionary analysis of the largest family of primate transcription factors, the Krüppel-type zinc finger (KZNF gene family. We identified and curated gene and pseudogene models for KZNFs in three primate species, chimpanzee, orangutan and rhesus macaque, to allow for a comparison with the curated set of human KZNFs. We show that the recent evolutionary history of primate KZNFs has been complex, including many lineage-specific duplications and deletions. We found 213 species-specific KZNFs, among them 7 human-specific and 23 chimpanzee-specific genes. Two human-specific genes were validated experimentally. Ten genes have been lost in humans and 13 in chimpanzees, either through deletion or pseudogenization. We also identified 30 KZNF orthologs with human-specific and 42 with chimpanzee-specific sequence changes that are predicted to affect DNA binding properties of the proteins. Eleven of these genes show signatures of accelerated evolution, suggesting positive selection between humans and chimpanzees. During primate evolution the most extensive re-shaping of the KZNF repertoire, including most gene additions, pseudogenizations, and structural changes occurred within the subfamily homininae. Using zinc finger (ZNF binding predictions, we suggest potential impact these changes have had on human gene regulatory networks. The large species differences in this family of TFs stands in stark contrast to the overall high conservation of primate genomes and potentially represents a potent driver of primate evolution.

  13. GeoChip-based insights into the microbial functional gene repertoire of marine sponges (high microbial abundance, low microbial abundance) and seawater

    KAUST Repository

    Bayer, Kristina

    2015-01-08

    The GeoChip 4.2 gene array was employed to interrogate the microbial functional gene repertoire of sponges and seawater collected from the Red Sea and the Mediterranean. Complementary amplicon sequencing confirmed the microbial community composition characteristic of high microbial abundance (HMA) and low microbial abundance (LMA) sponges. By use of GeoChip, altogether 20 273 probes encoding for 627 functional genes and representing 16 gene categories were identified. Minimum curvilinear embedding analyses revealed a clear separation between the samples. The HMA/LMA dichotomy was stronger than any possible geographic pattern, which is shown here for the first time on the level of functional genes. However, upon inspection of individual genes, very few specific differences were discernible. Differences were related to microbial ammonia oxidation, ammonification, and archaeal autotrophic carbon fixation (higher gene abundance in sponges over seawater) as well as denitrification and radiation-stress-related genes (lower gene abundance in sponges over seawater). Except for few documented specific differences the functional gene repertoire between the different sources appeared largely similar. This study expands previous reports in that functional gene convergence is not only reported between HMA and LMA sponges but also between sponges and seawater.

  14. GeoChip-based insights into the microbial functional gene repertoire of marine sponges (high microbial abundance, low microbial abundance) and seawater

    KAUST Repository

    Bayer, Kristina; Moitinho-Silva, Lucas; Brü mmer, Franz; Cannistraci, Carlo V.; Ravasi, Timothy; Hentschel, Ute

    2015-01-01

    The GeoChip 4.2 gene array was employed to interrogate the microbial functional gene repertoire of sponges and seawater collected from the Red Sea and the Mediterranean. Complementary amplicon sequencing confirmed the microbial community composition characteristic of high microbial abundance (HMA) and low microbial abundance (LMA) sponges. By use of GeoChip, altogether 20 273 probes encoding for 627 functional genes and representing 16 gene categories were identified. Minimum curvilinear embedding analyses revealed a clear separation between the samples. The HMA/LMA dichotomy was stronger than any possible geographic pattern, which is shown here for the first time on the level of functional genes. However, upon inspection of individual genes, very few specific differences were discernible. Differences were related to microbial ammonia oxidation, ammonification, and archaeal autotrophic carbon fixation (higher gene abundance in sponges over seawater) as well as denitrification and radiation-stress-related genes (lower gene abundance in sponges over seawater). Except for few documented specific differences the functional gene repertoire between the different sources appeared largely similar. This study expands previous reports in that functional gene convergence is not only reported between HMA and LMA sponges but also between sponges and seawater.

  15. Sequence-Based Discovery Demonstrates That Fixed Light Chain Human Transgenic Rats Produce a Diverse Repertoire of Antigen-Specific Antibodies

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    Katherine E. Harris

    2018-04-01

    Full Text Available We created a novel transgenic rat that expresses human antibodies comprising a diverse repertoire of heavy chains with a single common rearranged kappa light chain (IgKV3-15-JK1. This fixed light chain animal, called OmniFlic, presents a unique system for human therapeutic antibody discovery and a model to study heavy chain repertoire diversity in the context of a constant light chain. The purpose of this study was to analyze heavy chain variable gene usage, clonotype diversity, and to describe the sequence characteristics of antigen-specific monoclonal antibodies (mAbs isolated from immunized OmniFlic animals. Using next-generation sequencing antibody repertoire analysis, we measured heavy chain variable gene usage and the diversity of clonotypes present in the lymph node germinal centers of 75 OmniFlic rats immunized with 9 different protein antigens. Furthermore, we expressed 2,560 unique heavy chain sequences sampled from a diverse set of clonotypes as fixed light chain antibody proteins and measured their binding to antigen by ELISA. Finally, we measured patterns and overall levels of somatic hypermutation in the full B-cell repertoire and in the 2,560 mAbs tested for binding. The results demonstrate that OmniFlic animals produce an abundance of antigen-specific antibodies with heavy chain clonotype diversity that is similar to what has been described with unrestricted light chain use in mammals. In addition, we show that sequence-based discovery is a highly effective and efficient way to identify a large number of diverse monoclonal antibodies to a protein target of interest.

  16. A depauperate immune repertoire precedes evolution of sociality in bees.

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    Barribeau, Seth M; Sadd, Ben M; du Plessis, Louis; Brown, Mark J F; Buechel, Severine D; Cappelle, Kaat; Carolan, James C; Christiaens, Olivier; Colgan, Thomas J; Erler, Silvio; Evans, Jay; Helbing, Sophie; Karaus, Elke; Lattorff, H Michael G; Marxer, Monika; Meeus, Ivan; Näpflin, Kathrin; Niu, Jinzhi; Schmid-Hempel, Regula; Smagghe, Guy; Waterhouse, Robert M; Yu, Na; Zdobnov, Evgeny M; Schmid-Hempel, Paul

    2015-04-24

    Sociality has many rewards, but can also be dangerous, as high population density and low genetic diversity, common in social insects, is ideal for parasite transmission. Despite this risk, honeybees and other sequenced social insects have far fewer canonical immune genes relative to solitary insects. Social protection from infection, including behavioral responses, may explain this depauperate immune repertoire. Here, based on full genome sequences, we describe the immune repertoire of two ecologically and commercially important bumblebee species that diverged approximately 18 million years ago, the North American Bombus impatiens and European Bombus terrestris. We find that the immune systems of these bumblebees, two species of honeybee, and a solitary leafcutting bee, are strikingly similar. Transcriptional assays confirm the expression of many of these genes in an immunological context and more strongly in young queens than males, affirming Bateman's principle of greater investment in female immunity. We find evidence of positive selection in genes encoding antiviral responses, components of the Toll and JAK/STAT pathways, and serine protease inhibitors in both social and solitary bees. Finally, we detect many genes across pathways that differ in selection between bumblebees and honeybees, or between the social and solitary clades. The similarity in immune complement across a gradient of sociality suggests that a reduced immune repertoire predates the evolution of sociality in bees. The differences in selection on immune genes likely reflect divergent pressures exerted by parasites across social contexts.

  17. Dynamic evolution of bitter taste receptor genes in vertebrates

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    Jones Gareth

    2009-01-01

    Full Text Available Abstract Background Sensing bitter tastes is crucial for many animals because it can prevent them from ingesting harmful foods. This process is mainly mediated by the bitter taste receptors (T2R, which are largely expressed in the taste buds. Previous studies have identified some T2R gene repertoires, and marked variation in repertoire size has been noted among species. However, the mechanisms underlying the evolution of vertebrate T2R genes remain poorly understood. Results To better understand the evolutionary pattern of these genes, we identified 16 T2R gene repertoires based on the high coverage genome sequences of vertebrates and studied the evolutionary changes in the number of T2R genes during birth-and-death evolution using the reconciled-tree method. We found that the number of T2R genes and the fraction of pseudogenes vary extensively among species. Based on the results of phylogenetic analysis, we showed that T2R gene families in teleost fishes are more diverse than those in tetrapods. In addition to the independent gene expansions in teleost fishes, frogs and mammals, lineage-specific gene duplications were also detected in lizards. Furthermore, extensive gains and losses of T2R genes were detected in each lineage during their evolution, resulting in widely differing T2R gene repertoires. Conclusion These results further support the hypotheses that T2R gene repertoires are closely related to the dietary habits of different species and that birth-and-death evolution is associated with adaptations to dietary changes.

  18. Evolution of the Immune Repertoire with and without Somatic DNA Recombination

    NARCIS (Netherlands)

    Takumi, K.; Hogeweg, P.

    1998-01-01

    Repertoire of an immune system is a set of antigen receptors each having a unique specificity to bind an antigen. In many vertebrate species, antigen receptors are produced via combinatorial arrangements of DNA segments in specialized immune cells. Due to this molecular mechanism, repertoire

  19. Genomic and transcriptomic insights into the cytochrome P450 monooxygenase gene repertoire in the rice pest brown planthopper, Nilaparvata lugens.

    Science.gov (United States)

    Lao, Shu-Hua; Huang, Xiao-Hui; Huang, Hai-Jian; Liu, Cheng-Wen; Zhang, Chuan-Xi; Bao, Yan-Yuan

    2015-11-01

    The cytochrome P450 monooxygenase (P450) gene family is one of the most abundant eukaryotic gene families that encode detoxification enzymes. In this study, we identified an abundance of P450 gene repertoire through genome- and transcriptome-wide analysis in the brown planthopper (Nilaparvata lugens), the most destructive rice pest in Asia. Detailed gene information including the exon-intron organization, size, transcription orientation and distribution in the genome revealed that many P450 loci were closely situated on the same scaffold, indicating frequent occurrence of gene duplications. Insecticide-response expression profiling revealed that imidacloprid significantly increased NlCYP6CS1v2, NLCYP4CE1v2, NlCYP4DE1, NlCYP417A1v2 and NlCYP439A1 expression; while triazophos and deltamethrin notably enhanced NlCYP303A1 expression. Expression analysis at the developmental stage showed the egg-, nymph-, male- and female-specific expression patterns of N. lugens P450 genes. These novel findings will be helpful for clarifying the P450 functions in physiological processes including development, reproduction and insecticide resistance in this insect species. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Expressed var gene repertoire and variant surface antigen diversity in a shrinking Plasmodium falciparum population.

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    Carlos, Bianca C; Fotoran, Wesley L; Menezes, Maria J; Cabral, Fernanda J; Bastos, Marcele F; Costa, Fabio T M; Sousa-Neto, Jayme A; Ribolla, Paulo E M; Wunderlich, Gerhard; Ferreira, Marcelo U

    2016-11-01

    The var gene-encoded erythrocyte membrane protein-1 of Plasmodium falciparum (PfEMP-1) is the main variant surface antigen (VSA) expressed on infected erythrocytes. The rate at which antibody responses to VSA expressed by circulating parasites are acquired depends on the size of the local VSA repertoire and the frequency of exposure to new VSA. Because parasites from areas with declining malaria endemicity, such as the Amazon, typically express a restricted PfEMP-1 repertoire, we hypothesized that Amazonians would rapidly acquire antibodies to most locally circulating VSA. Consistent with our expectations, the analysis of 5878 sequence tags expressed by 10 local P. falciparum samples revealed little PfEMP-1 DBL1α domain diversity. Among the most commonly expressed DBL1α types, 45% were shared by two or more independent parasite lines. Nevertheless, Amazonians displayed major gaps in their repertoire of anti-VSA antibodies, although the breadth of anti-VSA antibody responses correlated positively with their cumulative exposure to malaria. We found little antibody cross-reactivity even when testing VSA from related parasites expressing the same dominant DBL1α types. We conclude that variant-specific immunity to P. falciparum VSAs develops slowly despite the relatively restricted PfEMP-1 repertoire found in low-endemicity settings. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Sorted gene genealogies and species-specific nonsynonymous substitutions point to putative postmating prezygotic isolation genes in Allonemobius crickets

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    Suegene Noh

    2016-02-01

    Full Text Available In the Allonemobius socius complex of crickets, reproductive isolation is primarily accomplished via postmating prezygotic barriers. We tested seven protein-coding genes expressed in the male ejaculate for patterns of evolution consistent with a putative role as postmating prezygotic isolation genes. Our recently diverged species generally lacked sequence variation. As a result, ω-based tests were only mildly successful. Some of our genes showed evidence of elevated ω values on the internal branches of gene trees. In a couple of genes, these internal branches coincided with both species branching events of the species tree, between A. fasciatus and the other two species, and between A. socius and A. sp. nov. Tex. In comparison, more successful approaches were those that took advantage of the varying degrees of lineage sorting and allele sharing among our young species. These approaches were particularly powerful within the contact zone. Among the genes we tested we found genes with genealogies that indicated relatively advanced degrees of lineage sorting across both allopatric and contact zone alleles. Within a contact zone between two members of the species complex, only a subset of genes maintained allelic segregation despite evidence of ongoing gene flow in other genes. The overlap in these analyses was arginine kinase (AK and apolipoprotein A-1 binding protein (APBP. These genes represent two of the first examples of sperm maturation, capacitation, and motility proteins with fixed non-synonymous substitutions between species-specific alleles that may lead to postmating prezygotic isolation. Both genes express ejaculate proteins transferred to females during copulation and were previously identified through comparative proteomics. We discuss the potential function of these genes in the context of the specific postmating prezygotic isolation phenotype among our species, namely conspecific sperm precedence and the superior ability of

  2. Analysis of B Cell Repertoire Dynamics Following Hepatitis B Vaccination in Humans, and Enrichment of Vaccine-specific Antibody Sequences.

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    Galson, Jacob D; Trück, Johannes; Fowler, Anna; Clutterbuck, Elizabeth A; Münz, Márton; Cerundolo, Vincenzo; Reinhard, Claudia; van der Most, Robbert; Pollard, Andrew J; Lunter, Gerton; Kelly, Dominic F

    2015-12-01

    Generating a diverse B cell immunoglobulin repertoire is essential for protection against infection. The repertoire in humans can now be comprehensively measured by high-throughput sequencing. Using hepatitis B vaccination as a model, we determined how the total immunoglobulin sequence repertoire changes following antigen exposure in humans, and compared this to sequences from vaccine-specific sorted cells. Clonal sequence expansions were seen 7 days after vaccination, which correlated with vaccine-specific plasma cell numbers. These expansions caused an increase in mutation, and a decrease in diversity and complementarity-determining region 3 sequence length in the repertoire. We also saw an increase in sequence convergence between participants 14 and 21 days after vaccination, coinciding with an increase of vaccine-specific memory cells. These features allowed development of a model for in silico enrichment of vaccine-specific sequences from the total repertoire. Identifying antigen-specific sequences from total repertoire data could aid our understanding B cell driven immunity, and be used for disease diagnostics and vaccine evaluation.

  3. Ancestral and derived attributes of the dlx gene repertoire, cluster structure and expression patterns in an African cichlid fish

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    Renz Adina J

    2011-01-01

    Full Text Available Abstract Background Cichlid fishes have undergone rapid, expansive evolutionary radiations that are manifested in the diversification of their trophic morphologies, tooth patterning and coloration. Understanding the molecular mechanisms that underlie the cichlids' unique patterns of evolution requires a thorough examination of genes that pattern the neural crest, from which these diverse phenotypes are derived. Among those genes, the homeobox-containing Dlx gene family is of particular interest since it is involved in the patterning of the brain, jaws and teeth. Results In this study, we characterized the dlx genes of an African cichlid fish, Astatotilapia burtoni, to provide a baseline to later allow cross-species comparison within Cichlidae. We identified seven dlx paralogs (dlx1a, -2a, -4a, -3b, -4b, -5a and -6a, whose orthologies were validated with molecular phylogenetic trees. The intergenic regions of three dlx gene clusters (dlx1a-2a, dlx3b-4b, and dlx5a-6a were amplified with long PCR. Intensive cross-species comparison revealed a number of conserved non-coding elements (CNEs that are shared with other percomorph fishes. This analysis highlighted additional lineage-specific gains/losses of CNEs in different teleost fish lineages and a novel CNE that had previously not been identified. Our gene expression analyses revealed overlapping but distinct expression of dlx orthologs in the developing brain and pharyngeal arches. Notably, four of the seven A. burtoni dlx genes, dlx2a, dlx3b, dlx4a and dlx5a, were expressed in the developing pharyngeal teeth. Conclusion This comparative study of the dlx genes of A. burtoni has deepened our knowledge of the diversity of the Dlx gene family, in terms of gene repertoire, expression patterns and non-coding elements. We have identified possible cichlid lineage-specific changes, including losses of a subset of dlx expression domains in the pharyngeal teeth, which will be the targets of future functional

  4. Analysis of B Cell Repertoire Dynamics Following Hepatitis B Vaccination in Humans, and Enrichment of Vaccine-specific Antibody Sequences

    Directory of Open Access Journals (Sweden)

    Jacob D. Galson

    2015-12-01

    Full Text Available Generating a diverse B cell immunoglobulin repertoire is essential for protection against infection. The repertoire in humans can now be comprehensively measured by high-throughput sequencing. Using hepatitis B vaccination as a model, we determined how the total immunoglobulin sequence repertoire changes following antigen exposure in humans, and compared this to sequences from vaccine-specific sorted cells. Clonal sequence expansions were seen 7 days after vaccination, which correlated with vaccine-specific plasma cell numbers. These expansions caused an increase in mutation, and a decrease in diversity and complementarity-determining region 3 sequence length in the repertoire. We also saw an increase in sequence convergence between participants 14 and 21 days after vaccination, coinciding with an increase of vaccine-specific memory cells. These features allowed development of a model for in silico enrichment of vaccine-specific sequences from the total repertoire. Identifying antigen-specific sequences from total repertoire data could aid our understanding B cell driven immunity, and be used for disease diagnostics and vaccine evaluation.

  5. Characterization of the sortase repertoire in Bacillus anthracis.

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    Willy Aucher

    Full Text Available LPXTG proteins, present in most if not all Gram-positive bacteria, are known to be anchored by sortases to the bacterial peptidoglycan. More than one sortase gene is often encoded in a bacterial species, and each sortase is supposed to specifically anchor given LPXTG proteins, depending of the sequence of the C-terminal cell wall sorting signal (cwss, bearing an LPXTG motif or another recognition sequence. B. anthracis possesses three sortase genes. B. anthracis sortase deleted mutant strains are not affected in their virulence. To determine the sortase repertoires, we developed a genetic screen using the property of the gamma phage to lyse bacteria only when its receptor, GamR, an LPXTG protein, is exposed at the surface. We identified 10 proteins that contain a cell wall sorting signal and are covalently anchored to the peptidoglycan. Some chimeric proteins yielded phage lysis in all sortase mutant strains, suggesting that cwss proteins remained surface accessible in absence of their anchoring sortase, probably as a consequence of membrane localization of yet uncleaved precursor proteins. For definite assignment of the sortase repertoires, we consequently relied on a complementary test, using a biochemical approach, namely immunoblot experiments. The sortase anchoring nine of these proteins has thus been determined. The absence of virulence defect of the sortase mutants could be a consequence of the membrane localization of the cwss proteins.

  6. Evolutionary constraints shape caste-specific gene expression across 15 ant species.

    Science.gov (United States)

    Morandin, Claire; Mikheyev, Alexander S; Pedersen, Jes Søe; Helanterä, Heikki

    2017-05-01

    Development of polymorphic phenotypes from similar genomes requires gene expression differences. However, little is known about how morph-specific gene expression patterns vary on a broad phylogenetic scale. We hypothesize that evolution of morph-specific gene expression, and consequently morph-specific phenotypic evolution, may be constrained by gene essentiality and the amount of pleiotropic constraints. Here, we use comparative transcriptomics of queen and worker morphs, that is, castes, from 15 ant species to understand the constraints of morph-biased gene expression. In particular, we investigate how measures of evolutionary constraints at the sequence level (expression level, connectivity, and number of gene ontology [GO] terms) correlate with morph-biased expression. Our results show that genes indeed vary in their potential to become morph-biased. The existence of genes that are constrained in becoming caste-biased potentially limits the evolutionary decoupling of the caste phenotypes, that is, it might result in "caste load" occasioning from antagonistic fitness variation, similarly to sexually antagonistic fitness variation between males and females. On the other hand, we suggest that genes under low constraints are released from antagonistic variation and thus more likely to be co-opted for morph specific use. Overall, our results suggest that the factors that affect sequence evolutionary rates and evolution of plastic expression may largely overlap. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  7. High diversity of the T-cell receptor repertoire of tumor-infiltrating lymphocytes in basal cell carcinoma

    DEFF Research Database (Denmark)

    Omland, Silje H; Hamrouni, Abdelbasset; Gniadecki, Robert

    2017-01-01

    to determine the clonality of TCR and degree of overlap in TCR repertoires between skin resident T-cells and TILs. We found high diversity of the TCR repertoire in BCC and control skin with random V-J gene usage and similar CDR3-length distribution. Lack of TCR repertoire restriction indicates absence of tumor......Whether specific T-cell clones are present in tumor infiltrating lymphocytes (TILs) in BCC is unknown. We employed deep sequencing of mRNA coding for the T-cell receptor (TCR) chains α- and β to characterize the repertoire of TILs in BCC. V and J gene-usage and CDR3 length were computed...

  8. Effects of spaceflight on the immunoglobulin repertoire of unimmunized C57BL/6 mice

    Science.gov (United States)

    Ward, Claire; Rettig, Trisha A.; Hlavacek, Savannah; Bye, Bailey A.; Pecaut, Michael J.; Chapes, Stephen K.

    2018-02-01

    Spaceflight has been shown to suppress the adaptive immune response, altering the distribution and function of lymphocyte populations. B lymphocytes express highly specific and highly diversified receptors, known as immunoglobulins (Ig), that directly bind and neutralize pathogens. Ig diversity is achieved through the enzymatic splicing of gene segments within the genomic DNA of each B cell in a host. The collection of Ig specificities within a host, or Ig repertoire, has been increasingly characterized in both basic research and clinical settings using high-throughput sequencing technology (HTS). We utilized HTS to test the hypothesis that spaceflight affects the B-cell repertoire. To test this hypothesis, we characterized the impact of spaceflight on the unimmunized Ig repertoire of C57BL/6 mice that were flown aboard the International Space Station (ISS) during the Rodent Research One validation flight in comparison to ground controls. Individual gene segment usage was similar between ground control and flight animals, however, gene segment combinations and the junctions in which gene segments combine was varied among animals within and between treatment groups. We also found that spontaneous somatic mutations in the IgH and Igκ gene loci were not increased. These data suggest that space flight did not affect the B cell repertoire of mice flown and housed on the ISS over a short period of time.

  9. Quantitative measurement of pathogen specific human memory T cell repertoire diversity using a CDR3β-specific microarray

    Directory of Open Access Journals (Sweden)

    Gorski Jack

    2007-09-01

    Full Text Available Abstract Background Providing quantitative microarray data that is sensitive to very small differences in target sequence would be a useful tool in any number of venues where a sample can consist of a multiple related sequences present in various abundances. Examples of such applications would include measurement of pseudo species in viral infections and the measurement of species of antibodies or T cell receptors that constitute immune repertoires. Difficulties that must be overcome in such a method would be to account for cross-hybridization and for differences in hybridization efficiencies between the arrayed probes and their corresponding targets. We have used the memory T cell repertoire to an influenza-derived peptide as a test case for developing such a method. Results The arrayed probes were corresponded to a 17 nucleotide TCR-specific region that distinguished sequences differing by as little as a single nucleotide. Hybridization efficiency between highly related Cy5-labeled subject sequences was normalized by including an equimolar mixture of Cy3-labeled synthetic targets representing all 108 arrayed probes. The same synthetic targets were used to measure the degree of cross hybridization between probes. Reconstitution studies found the system sensitive to input ratios as low as 0.5% and accurate in measuring known input percentages (R2 = 0.81, R = 0.90, p 0.05. Conclusion This novel strategy appears to be robust and can be adapted to any situation where complex mixtures of highly similar sequences need to be quantitatively resolved.

  10. Recurrent Gene Duplication Leads to Diverse Repertoires of Centromeric Histones in Drosophila Species.

    Science.gov (United States)

    Kursel, Lisa E; Malik, Harmit S

    2017-06-01

    Despite their essential role in the process of chromosome segregation in most eukaryotes, centromeric histones show remarkable evolutionary lability. Not only have they been lost in multiple insect lineages, but they have also undergone gene duplication in multiple plant lineages. Based on detailed study of a handful of model organisms including Drosophila melanogaster, centromeric histone duplication is considered to be rare in animals. Using a detailed phylogenomic study, we find that Cid, the centromeric histone gene, has undergone at least four independent gene duplications during Drosophila evolution. We find duplicate Cid genes in D. eugracilis (Cid2), in the montium species subgroup (Cid3, Cid4) and in the entire Drosophila subgenus (Cid5). We show that Cid3, Cid4, and Cid5 all localize to centromeres in their respective species. Some Cid duplicates are primarily expressed in the male germline. With rare exceptions, Cid duplicates have been strictly retained after birth, suggesting that they perform nonredundant centromeric functions, independent from the ancestral Cid. Indeed, each duplicate encodes a distinct N-terminal tail, which may provide the basis for distinct protein-protein interactions. Finally, we show some Cid duplicates evolve under positive selection whereas others do not. Taken together, our results support the hypothesis that Drosophila Cid duplicates have subfunctionalized. Thus, these gene duplications provide an unprecedented opportunity to dissect the multiple roles of centromeric histones. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  11. Analysis of the clonal repertoire of gene-corrected cells in gene therapy.

    Science.gov (United States)

    Paruzynski, Anna; Glimm, Hanno; Schmidt, Manfred; Kalle, Christof von

    2012-01-01

    Gene therapy-based clinical phase I/II studies using integrating retroviral vectors could successfully treat different monogenetic inherited diseases. However, with increased efficiency of this therapy, severe side effects occurred in various gene therapy trials. In all cases, integration of the vector close to or within a proto-oncogene contributed substantially to the development of the malignancies. Thus, the in-depth analysis of integration site patterns is of high importance to uncover potential clonal outgrowth and to assess the safety of gene transfer vectors and gene therapy protocols. The standard and nonrestrictive linear amplification-mediated PCR (nrLAM-PCR) in combination with high-throughput sequencing exhibits technologies that allow to comprehensively analyze the clonal repertoire of gene-corrected cells and to assess the safety of the used vector system at an early stage on the molecular level. It enables clarifying the biological consequences of the vector system on the fate of the transduced cell. Furthermore, the downstream performance of real-time PCR allows a quantitative estimation of the clonality of individual cells and their clonal progeny. Here, we present a guideline that should allow researchers to perform comprehensive integration site analysis in preclinical and clinical studies. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Rules of song development and their use in vocal interactions by birds with large repertoires

    OpenAIRE

    Geberzahn Nicole; Hultsch Henrike

    2004-01-01

    Songbirds are well known for settling their disputes by vocal signals, and their singing plays a dominant role. Most studies on this issue have concentrated on bird species that develop and use small vocal repertoires. In this article we will go farther and focus on examples of how species with large song repertoires make use of their vocal competence. In particular, we will outline the study of interaction rules which have been elucidated by examining time- and pattern-specific relationships...

  13. Can rarefaction be used to estimate song repertoire size in birds?

    Directory of Open Access Journals (Sweden)

    Kathleen R. PESHEK, Daniel T. BLUMSTEIN

    2011-06-01

    Full Text Available Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is important for ecological and evolutionary studies of speciation, studies of sexual selection, as well as studies of how species may adapt their songs to various acoustic environments. There are several methods to estimate repertoire size, however prior studies discovered that all but a full numerical count of song types might have substantial inaccuracies associated with them. We evaluated a somewhat novel approach to estimate repertoire size—rarefaction; a technique ecologists use to measure species diversity on individual and population levels. Using the syllables within American robins’ Turdus migratorius repertoire, we compared the most commonly used techniques of estimating repertoires to the results of a rarefaction analysis. American robins have elaborate and unique songs with few syllables shared between individuals, and there is no evidence that robins mimic their neighbors. Thus, they are an ideal system in which to compare techniques. We found that the rarefaction technique results resembled that of the numerical count, and were better than two alternative methods (behavioral accumulation curves, and capture-recapture to estimate syllable repertoire size. Future estimates of repertoire size, particularly in vocally complex species, may benefit from using rarefaction techniques when numerical counts are unable to be performed [Current Zoology 57 (3: 300–306, 2011].

  14. Repertoire of intensive care unit pneumonia microbiota.

    Directory of Open Access Journals (Sweden)

    Sabri Bousbia

    Full Text Available Despite the considerable number of studies reported to date, the causative agents of pneumonia are not completely identified. We comprehensively applied modern and traditional laboratory diagnostic techniques to identify microbiota in patients who were admitted to or developed pneumonia in intensive care units (ICUs. During a three-year period, we tested the bronchoalveolar lavage (BAL of patients with ventilator-associated pneumonia, community-acquired pneumonia, non-ventilator ICU pneumonia and aspiration pneumonia, and compared the results with those from patients without pneumonia (controls. Samples were tested by amplification of 16S rDNA, 18S rDNA genes followed by cloning and sequencing and by PCR to target specific pathogens. We also included culture, amoeba co-culture, detection of antibodies to selected agents and urinary antigen tests. Based on molecular testing, we identified a wide repertoire of 160 bacterial species of which 73 have not been previously reported in pneumonia. Moreover, we found 37 putative new bacterial phylotypes with a 16S rDNA gene divergence ≥ 98% from known phylotypes. We also identified 24 fungal species of which 6 have not been previously reported in pneumonia and 7 viruses. Patients can present up to 16 different microorganisms in a single BAL (mean ± SD; 3.77 ± 2.93. Some pathogens considered to be typical for ICU pneumonia such as Pseudomonas aeruginosa and Streptococcus species can be detected as commonly in controls as in pneumonia patients which strikingly highlights the existence of a core pulmonary microbiota. Differences in the microbiota of different forms of pneumonia were documented.

  15. First insights into the vocal repertoire of infant and juvenile Southern white rhinoceros.

    Science.gov (United States)

    Linn, Sabrina N; Boeer, Michael; Scheumann, Marina

    2018-01-01

    Describing vocal repertoires represents an essential step towards gaining an overview about the complexity of acoustic communication in a given species. The analysis of infant vocalisations is essential for understanding the development and usage of species-specific vocalisations, but is often underrepresented, especially in species with long inter-birth intervals such as the white rhinoceros. Thus, this study aimed for the first time to characterise the infant and juvenile vocal repertoire of the Southern white rhinoceros and to relate these findings to the adult vocal repertoire. The behaviour of seven mother-reared white rhinoceros calves (two males, five females) and one hand-reared calf (male), ranging from one month to four years, was simultaneously audio and video-taped at three zoos. Normally reared infants and juveniles uttered four discriminable call types (Whine, Snort, Threat, and Pant) that were produced in different behavioural contexts. All call types were also uttered by the hand-reared calf. Call rates of Whines, but not of the other call types, decreased with age. These findings provide the first evidence that infant and juvenile rhinoceros utter specific call types in distinct contexts, even if they grow up with limited social interaction with conspecifics. By comparing our findings with the current literature on vocalisations of adult white rhinoceros and other solitary rhinoceros species, we discuss to which extent differences in the social lifestyle across species affect acoustic communication in mammals.

  16. First insights into the vocal repertoire of infant and juvenile Southern white rhinoceros

    Science.gov (United States)

    Boeer, Michael; Scheumann, Marina

    2018-01-01

    Describing vocal repertoires represents an essential step towards gaining an overview about the complexity of acoustic communication in a given species. The analysis of infant vocalisations is essential for understanding the development and usage of species-specific vocalisations, but is often underrepresented, especially in species with long inter-birth intervals such as the white rhinoceros. Thus, this study aimed for the first time to characterise the infant and juvenile vocal repertoire of the Southern white rhinoceros and to relate these findings to the adult vocal repertoire. The behaviour of seven mother-reared white rhinoceros calves (two males, five females) and one hand-reared calf (male), ranging from one month to four years, was simultaneously audio and video-taped at three zoos. Normally reared infants and juveniles uttered four discriminable call types (Whine, Snort, Threat, and Pant) that were produced in different behavioural contexts. All call types were also uttered by the hand-reared calf. Call rates of Whines, but not of the other call types, decreased with age. These findings provide the first evidence that infant and juvenile rhinoceros utter specific call types in distinct contexts, even if they grow up with limited social interaction with conspecifics. By comparing our findings with the current literature on vocalisations of adult white rhinoceros and other solitary rhinoceros species, we discuss to which extent differences in the social lifestyle across species affect acoustic communication in mammals. PMID:29513670

  17. Primer sets for cloning the human repertoire of T cell Receptor Variable regions.

    Science.gov (United States)

    Boria, Ilenia; Cotella, Diego; Dianzani, Irma; Santoro, Claudio; Sblattero, Daniele

    2008-08-29

    Amplification and cloning of naïve T cell Receptor (TR) repertoires or antigen-specific TR is crucial to shape immune response and to develop immuno-based therapies. TR variable (V) regions are encoded by several genes that recombine during T cell development. The cloning of expressed genes as large diverse libraries from natural sources relies upon the availability of primers able to amplify as many V genes as possible. Here, we present a list of primers computationally designed on all functional TR V and J genes listed in the IMGT, the ImMunoGeneTics information system. The list consists of unambiguous or degenerate primers suitable to theoretically amplify and clone the entire TR repertoire. We show that it is possible to selectively amplify and clone expressed TR V genes in one single RT-PCR step and from as little as 1000 cells. This new primer set will facilitate the creation of more diverse TR libraries than has been possible using currently available primer sets.

  18. Uncovering the Legionella genus effector repertoire - strength in diversity and numbers

    Science.gov (United States)

    Burstein, David; Amaro, Francisco; Zusman, Tal; Lifshitz, Ziv; Cohen, Ofir; Gilbert, Jack A; Pupko, Tal; Shuman, Howard A; Segal, Gil

    2016-01-01

    Infection by the human pathogen Legionella pneumophila relies on the translocation of ~300 virulence proteins, termed effectors, which manipulate host-cell processes. However, almost no information exists regarding effectors in other Legionella pathogens. Here we sequenced, assembled and characterized the genomes of 38 Legionella species, and predicted their effector repertoire using a previously validated machine-learning approach. This analysis revealed a treasure trove of 5,885 predicted effectors. The effector repertoire of different Legionella species was found to be largely non-overlapping, and only seven core-effectors were shared among all species studied. Species-specific effectors had atypically low GC content, suggesting exogenous acquisition, possibly from their natural protozoan hosts. Furthermore, we detected numerous novel conserved effector domains, and discovered new domain combinations, which allowed inferring yet undescribed effector functions. The effector collection and network of domain architectures described here can serve as a roadmap for future studies of effector function and evolution. PMID:26752266

  19. Identification of Complete Repertoire of Apis florea Odorant Receptors Reveals Complex Orthologous Relationships with Apis mellifera

    Science.gov (United States)

    Karpe, Snehal D.; Jain, Rikesh; Brockmann, Axel; Sowdhamini, Ramanathan

    2016-01-01

    Abstract We developed a computational pipeline for homology based identification of the complete repertoire of olfactory receptor (OR) genes in the Asian honey bee species, Apis florea. Apis florea is phylogenetically the most basal honey bee species and also the most distant sister species to the Western honey bee Apis mellifera, for which all OR genes had been identified before. Using our pipeline, we identified 180 OR genes in A. florea, which is very similar to the number of ORs identified in A. mellifera (177 ORs). Many characteristics of the ORs including gene structure, synteny of tandemly repeated ORs and basic phylogenetic clustering are highly conserved. The composite phylogenetic tree of A. florea and A. mellifera ORs could be divided into 21 clades which are in harmony with the existing Hymenopteran tree. However, we found a few nonorthologous OR relationships between both species as well as independent pseudogenization of ORs suggesting separate evolutionary changes. Particularly, a subgroup of the OR gene clade XI, which had been hypothesized to code cuticular hydrocarbon receptors showed a high number of species-specific ORs. RNAseq analysis detected a total number of 145 OR transcripts in male and 162 in female antennae. Most of the OR genes were highly expressed on the female antennae. However, we detected five distinct male-biased OR genes, out of which three genes (AfOr11, AfOr18, AfOr170P) were shown to be male-biased in A. mellifera, too, thus corroborating a behavioral function in sex-pheromone communication. PMID:27540087

  20. Genome-wide identification of nuclear receptor (NR) superfamily genes in the copepod Tigriopus japonicus.

    Science.gov (United States)

    Hwang, Dae-Sik; Lee, Bo-Young; Kim, Hui-Su; Lee, Min Chul; Kyung, Do-Hyun; Om, Ae-Son; Rhee, Jae-Sung; Lee, Jae-Seong

    2014-11-18

    Nuclear receptors (NRs) are a large superfamily of proteins defined by a DNA-binding domain (DBD) and a ligand-binding domain (LBD). They function as transcriptional regulators to control expression of genes involved in development, homeostasis, and metabolism. The number of NRs differs from species to species, because of gene duplications and/or lineage-specific gene losses during metazoan evolution. Many NRs in arthropods interact with the ecdysteroid hormone and are involved in ecdysone-mediated signaling in arthropods. The nuclear receptor superfamily complement has been reported in several arthropods, including crustaceans, but not in copepods. We identified the entire NR repertoire of the copepod Tigriopus japonicus, which is an important marine model species for ecotoxicology and environmental genomics. Using whole genome and transcriptome sequences, we identified a total of 31 nuclear receptors in the genome of T. japonicus. Nomenclature of the nuclear receptors was determined based on the sequence similarities of the DNA-binding domain (DBD) and ligand-binding domain (LBD). The 7 subfamilies of NRs separate into five major clades (subfamilies NR1, NR2, NR3, NR4, and NR5/6). Although the repertoire of NR members in, T. japonicus was similar to that reported for other arthropods, there was an expansion of the NR1 subfamily in Tigriopus japonicus. The twelve unique nuclear receptors identified in T. japonicus are members of NR1L. This expansion may be a unique lineage-specific feature of crustaceans. Interestingly, E78 and HR83, which are present in other arthropods, were absent from the genomes of T. japonicus and two congeneric copepod species (T. japonicus and Tigriopus californicus), suggesting copepod lineage-specific gene loss. We identified all NR receptors present in the copepod, T. japonicus. Knowledge of the copepod nuclear receptor repertoire will contribute to a better understanding of copepod- and crustacean-specific NR evolution.

  1. Immunoglobulin gene repertoire diversification and selection in the stomach – from gastritis to gastric lymphomas

    Directory of Open Access Journals (Sweden)

    Miri eMichaeli

    2014-06-01

    Full Text Available Chronic gastritis is characterized by gastric mucosal inflammation due to autoimmune responses or infection, frequently with Helicobacter pylori. Gastritis with H. pylori background can cause gastric mucosa-associated lymphoid tissue lymphoma (MALT-L, which sometimes further transforms into diffuse large B cell lymphoma (DLBCL. However, gastric DLBCL can also be initiated de novo. The mechanisms underlying transformation into DLBCL are not completely understood. We analyzed immunoglobulin repertoires and clonal trees to investigate whether and how immunoglobulin gene repertoires, clonal diversification and selection in gastritis, gastric MALT-L and DLBCL differ from each other and from normal responses. The two gastritis types (positive or negative for H. pylori had similarly diverse repertoires. MALT-L dominant clones presented higher diversification and longer mutational histories compared with all other conditions. DLBCL dominant clones displayed lower clonal diversification, suggesting the transforming events are triggered by similar responses in different patients. These results are surprising, as we expected to find similarities between the dominant clones of gastritis and MALT-L and between those of MALT-L and DLBCL.

  2. Cloning of the Repertoire of Individual Plasmodium falciparum var Genes Using Transformation Associated Recombination (TAR)

    Science.gov (United States)

    Schmid, Christoph D.; Bühlmann, Tobias; Louis, Edward J.; Beck, Hans-Peter

    2011-01-01

    One of the major virulence factors of the malaria causing parasite is the Plasmodium falciparum encoded erythrocyte membrane protein 1 (PfEMP1). It is translocated to It the membrane of infected erythrocytes and expressed from approximately 60 var genes in a mutually exclusive manner. Switching of var genes allows the parasite to alter functional and antigenic properties of infected erythrocytes, to escape the immune defense and to establish chronic infections. We have developed an efficient method for isolating VAR genes from telomeric and other genome locations by adapting transformation-associated recombination (TAR) cloning, which can then be analyzed and sequenced. For this purpose, three plasmids each containing a homologous sequence representing the upstream regions of the group A, B, and C var genes and a sequence homologous to the conserved acidic terminal segment (ATS) of var genes were generated. Co-transfection with P. falciparum strain ITG2F6 genomic DNA in yeast cells yielded 200 TAR clones. The relative frequencies of clones from each group were not biased. Clones were screened by PCR, as well as Southern blotting, which revealed clones missed by PCR due to sequence mismatches with the primers. Selected clones were transformed into E. coli and further analyzed by RFLP and end sequencing. Physical analysis of 36 clones revealed 27 distinct types potentially representing 50% of the var gene repertoire. Three clones were selected for sequencing and assembled into single var gene containing contigs. This study demonstrates that it is possible to rapidly obtain the repertoire of var genes from P. falciparum within a single set of cloning experiments. This technique can be applied to individual isolates which will provide a detailed picture of the diversity of var genes in the field. This is a powerful tool to overcome the obstacles with cloning and assembly of multi-gene families by simultaneously cloning each member. PMID:21408186

  3. Rules of song development and their use in vocal interactions by birds with large repertoires.

    Science.gov (United States)

    Geberzahn, Nicole; Hultsch, Henrike

    2004-06-01

    Songbirds are well known for settling their disputes by vocal signals, and their singing plays a dominant role. Most studies on this issue have concentrated on bird species that develop and use small vocal repertoires. In this article we will go farther and focus on examples of how species with large song repertoires make use of their vocal competence. In particular, we will outline the study of interaction rules which have been elucidated by examining time- and pattern-specific relationships between signals exchanged by territorial neighbors. First we present an inquiry into the rules of song learning and development. In birds with large song repertoires, the ontogeny of such rules proceeds along a number of trajectories which help in understanding the often remarkable accomplishments of adult birds. In both approaches, our model species will be the Common Nightingale Luscinia megarhynchos that has been investigated intensively in the field and in the laboratory.

  4. Lineage-specific enhancers activate self-renewal genes in macrophages and embryonic stem cells

    OpenAIRE

    Soucie, E.L.; Weng, Z.; Geirsdottir, L.; Molawi, K.; Maurizio, J.; Fenouil, R.; Mossadegh-Keller, N.; Gimenez, G.; VanHille, L.; Beniazza, M.; Favret, J.; Berruyer, C.; Perrin, P.; Hacohen, N.; Andrau, J.C.

    2016-01-01

    Differentiated macrophages can self-renew in tissues and expand long-term in culture, but the gene regulatory mechanisms that accomplish self-renewal in the differentiated state have remained unknown. Here we show that in mice, the transcription factors MafB and c-Maf repress a macrophage-specific enhancer repertoire associated with a gene network controlling self-renewal. Single cell analysis revealed that, in vivo, proliferating resident macrophages can access this network by transient down...

  5. Discrimination of the Lactobacillus acidophilus group using sequencing, species-specific PCR and SNaPshot mini-sequencing technology based on the recA gene.

    Science.gov (United States)

    Huang, Chien-Hsun; Chang, Mu-Tzu; Huang, Mu-Chiou; Wang, Li-Tin; Huang, Lina; Lee, Fwu-Ling

    2012-10-01

    To clearly identify specific species and subspecies of the Lactobacillus acidophilus group using phenotypic and genotypic (16S rDNA sequence analysis) techniques alone is difficult. The aim of this study was to use the recA gene for species discrimination in the L. acidophilus group, as well as to develop a species-specific primer and single nucleotide polymorphism primer based on the recA gene sequence for species and subspecies identification. The average sequence similarity for the recA gene among type strains was 80.0%, and most members of the L. acidophilus group could be clearly distinguished. The species-specific primer was designed according to the recA gene sequencing, which was employed for polymerase chain reaction with the template DNA of Lactobacillus strains. A single 231-bp species-specific band was found only in L. delbrueckii. A SNaPshot mini-sequencing assay using recA as a target gene was also developed. The specificity of the mini-sequencing assay was evaluated using 31 strains of L. delbrueckii species and was able to unambiguously discriminate strains belonging to the subspecies L. delbrueckii subsp. bulgaricus. The phylogenetic relationships of most strains in the L. acidophilus group can be resolved using recA gene sequencing, and a novel method to identify the species and subspecies of the L. delbrueckii and L. delbrueckii subsp. bulgaricus was developed by species-specific polymerase chain reaction combined with SNaPshot mini-sequencing. Copyright © 2012 Society of Chemical Industry.

  6. The scavenger receptor repertoire in six cnidarian species and its putative role in cnidarian-dinoflagellate symbiosis

    Directory of Open Access Journals (Sweden)

    Emilie F. Neubauer

    2016-11-01

    Full Text Available Many cnidarians engage in a mutualism with endosymbiotic photosynthetic dinoflagellates that forms the basis of the coral reef ecosystem. Interpartner interaction and regulation includes involvement of the host innate immune system. Basal metazoans, including cnidarians have diverse and complex innate immune repertoires that are just beginning to be described. Scavenger receptors (SR are a diverse superfamily of innate immunity genes that recognize a broad array of microbial ligands and participate in phagocytosis of invading microbes. The superfamily includes subclades named SR-A through SR-I that are categorized based on the arrangement of sequence domains including the scavenger receptor cysteine rich (SRCR, the C-type lectin (CTLD and the CD36 domains. Previous functional and gene expression studies on cnidarian-dinoflagellate symbiosis have implicated SR-like proteins in interpartner communication and regulation. In this study, we characterized the SR repertoire from a combination of genomic and transcriptomic resources from six cnidarian species in the Class Anthozoa. We combined these bioinformatic analyses with functional experiments using the SR inhibitor fucoidan to explore a role for SRs in cnidarian symbiosis and immunity. Bioinformatic searches revealed a large diversity of SR-like genes that resembled SR-As, SR-Bs, SR-Es and SR-Is. SRCRs, CTLDs and CD36 domains were identified in multiple sequences in combinations that were highly homologous to vertebrate SRs as well as in proteins with novel domain combinations. Phylogenetic analyses of CD36 domains of the SR-B-like sequences from a diversity of metazoans grouped cnidarian with bilaterian sequences separate from other basal metazoans. All cnidarian sequences grouped together with moderate support in a subclade separately from bilaterian sequences. Functional experiments were carried out on the sea anemone Aiptasia pallida that engages in a symbiosis with Symbiodinium minutum

  7. Element repertoire: change and development with age in Whitethroat Sylvia communis song

    DEFF Research Database (Denmark)

    Balsby, T.J.S.; Hansen, P.

    2010-01-01

    Song repertoires are often important determining factors in sexual selection. In several species, older males have larger repertoires than 1-year-old males. The development of large song repertoires by an individual is, however, poorly understood. We studied song element repertoire changes in five...... based on the first-year repertoire, which may explain why large song repertoires are mainly expressed by males at least 2 years of age. It would appear, therefore, that song element repertoire size could be a reliable signal of male age....

  8. Primer sets for cloning the human repertoire of T cell Receptor Variable regions

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    Santoro Claudio

    2008-08-01

    Full Text Available Abstract Background Amplification and cloning of naïve T cell Receptor (TR repertoires or antigen-specific TR is crucial to shape immune response and to develop immuno-based therapies. TR variable (V regions are encoded by several genes that recombine during T cell development. The cloning of expressed genes as large diverse libraries from natural sources relies upon the availability of primers able to amplify as many V genes as possible. Results Here, we present a list of primers computationally designed on all functional TR V and J genes listed in the IMGT®, the ImMunoGeneTics information system®. The list consists of unambiguous or degenerate primers suitable to theoretically amplify and clone the entire TR repertoire. We show that it is possible to selectively amplify and clone expressed TR V genes in one single RT-PCR step and from as little as 1000 cells. Conclusion This new primer set will facilitate the creation of more diverse TR libraries than has been possible using currently available primer sets.

  9. In-Depth Analysis of Human Neonatal and Adult IgM Antibody Repertoires

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    Binbin Hong

    2018-02-01

    Full Text Available Although high-throughput sequencing and associated bioinformatics technologies have enabled the in-depth, sequence-based characterization of human immune repertoires, only a few studies on a relatively small number of sequences explored the characteristics of antibody repertoires in neonates, with contradictory conclusions. To gain a more comprehensive understanding of the human IgM antibody repertoire, we performed Illumina sequencing and IMGT/HighV-QUEST analysis of IgM heavy chain repertoire of the B lymphocytes from the cord blood (CB of neonates, as well as the repertoire from peripheral blood of healthy human adults (HH. The comparative study revealed unexpectedly high levels of similarity between the neonatal and adult repertoires. In both repertoires, the VDJ gene usage showed no significant difference, and the most frequently used VDJ gene was IGHV4-59, IGHD3-10, and IGHJ3. The average amino acid (aa length of CDR1 (CB: 8.5, HH: 8.4 and CDR2 (CB: 7.6, HH: 7.5, as well as the aa composition and the average hydrophobicity of the CDR3 demonstrated no significant difference between the two repertories. However, the average aa length of CDR3 was longer in the HH repertoire than the CB repertoire (CB: 14.5, HH: 15.5. Besides, the frequencies of aa mutations in CDR1 (CB: 19.33%, HH: 25.84% and CDR2 (CB: 9.26%, HH: 17.82% were higher in the HH repertoire compared to the CB repertoire. Interestingly, the most prominent difference between the two repertoires was the occurrence of N2 addition (CB: 64.87%, HH: 85.69%, a process that occurs during V-D-J recombination for introducing random nucleotide additions between D- and J-gene segments. The antibody repertoire of healthy adults was more diverse than that of neonates largely due to the higher occurrence of N2 addition. These findings may lead to a better understanding of antibody development and evolution pathways and may have potential practical value for facilitating the generation of more

  10. CRDB: database of chemosensory receptor gene families in vertebrate.

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    Dong Dong

    Full Text Available Chemosensory receptors (CR are crucial for animals to sense the environmental changes and survive on earth. The emergence of whole-genome sequences provides us an opportunity to identify the entire CR gene repertoires. To completely gain more insight into the evolution of CR genes in vertebrates, we identified the nearly all CR genes in 25 vertebrates using homology-based approaches. Among these CR gene repertoires, nearly half of them were identified for the first time in those previously uncharacterized species, such as the guinea pig, giant panda and elephant, etc. Consistent with previous findings, we found that the numbers of CR genes vary extensively among different species, suggesting an extreme form of 'birth-and-death' evolution. For the purpose of facilitating CR gene analysis, we constructed a database with the goals to provide a resource for CR genes annotation and a web tool for exploring their evolutionary patterns. Besides a search engine for the gene extraction from a specific chromosome region, an easy-to-use phylogenetic analysis tool was also provided to facilitate online phylogeny study of CR genes. Our work can provide a rigorous platform for further study on the evolution of CR genes in vertebrates.

  11. Song repertoire size correlates with measures of body size in Eurasian blackbirds

    DEFF Research Database (Denmark)

    Hesler, Nana; Mundry, Roger; Sacher, Thomas

    2012-01-01

    In most oscine bird species males possess a repertoire of different song patterns. The size of these repertoires is assumed to serve as an honest signal of male quality. The Eurasian blackbird’s (Turdus merula) song contains a large repertoire of different element types with a flexible song...... organisation. Here we investigated whether repertoire size in Eurasian blackbirds correlates with measures of body size, namely length of wing, 8th primary, beak and tarsus. So far, very few studies have investigated species with large repertoires and a flexible song organisation in this context. We found...... positive correlations, meaning that larger males had larger repertoires. Larger males may have better fighting abilities and, thus, advantages in territorial defence. Larger structural body size may also reflect better conditions during early development. Therefore, under the assumption that body size...

  12. Functional requirements driving the gene duplication in 12 Drosophila species.

    Science.gov (United States)

    Zhong, Yan; Jia, Yanxiao; Gao, Yang; Tian, Dacheng; Yang, Sihai; Zhang, Xiaohui

    2013-08-15

    Gene duplication supplies the raw materials for novel gene functions and many gene families arisen from duplication experience adaptive evolution. Most studies of young duplicates have focused on mammals, especially humans, whereas reports describing their genome-wide evolutionary patterns across the closely related Drosophila species are rare. The sequenced 12 Drosophila genomes provide the opportunity to address this issue. In our study, 3,647 young duplicate gene families were identified across the 12 Drosophila species and three types of expansions, species-specific, lineage-specific and complex expansions, were detected in these gene families. Our data showed that the species-specific young duplicate genes predominated (86.6%) over the other two types. Interestingly, many independent species-specific expansions in the same gene family have been observed in many species, even including 11 or 12 Drosophila species. Our data also showed that the functional bias observed in these young duplicate genes was mainly related to responses to environmental stimuli and biotic stresses. This study reveals the evolutionary patterns of young duplicates across 12 Drosophila species on a genomic scale. Our results suggest that convergent evolution acts on young duplicate genes after the species differentiation and adaptive evolution may play an important role in duplicate genes for adaption to ecological factors and environmental changes in Drosophila.

  13. The map-1 gene family in root-knot nematodes, Meloidogyne spp.: a set of taxonomically restricted genes specific to clonal species.

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    Iva Tomalova

    Full Text Available Taxonomically restricted genes (TRGs, i.e., genes that are restricted to a limited subset of phylogenetically related organisms, may be important in adaptation. In parasitic organisms, TRG-encoded proteins are possible determinants of the specificity of host-parasite interactions. In the root-knot nematode (RKN Meloidogyne incognita, the map-1 gene family encodes expansin-like proteins that are secreted into plant tissues during parasitism, thought to act as effectors to promote successful root infection. MAP-1 proteins exhibit a modular architecture, with variable number and arrangement of 58 and 13-aa domains in their central part. Here, we address the evolutionary origins of this gene family using a combination of bioinformatics and molecular biology approaches. Map-1 genes were solely identified in one single member of the phylum Nematoda, i.e., the genus Meloidogyne, and not detected in any other nematode, thus indicating that the map-1 gene family is indeed a TRG family. A phylogenetic analysis of the distribution of map-1 genes in RKNs further showed that these genes are specifically present in species that reproduce by mitotic parthenogenesis, with the exception of M. floridensis, and could not be detected in RKNs reproducing by either meiotic parthenogenesis or amphimixis. These results highlight the divergence between mitotic and meiotic RKN species as a critical transition in the evolutionary history of these parasites. Analysis of the sequence conservation and organization of repeated domains in map-1 genes suggests that gene duplication(s together with domain loss/duplication have contributed to the evolution of the map-1 family, and that some strong selection mechanism may be acting upon these genes to maintain their functional role(s in the specificity of the plant-RKN interactions.

  14. Putative and unique gene sequence utilization for the design of species specific probes as modeled by Lactobacillus plantarum

    Science.gov (United States)

    The concept of utilizing putative and unique gene sequences for the design of species specific probes was tested. The abundance profile of assigned functions within the Lactobacillus plantarum genome was used for the identification of the putative and unique gene sequence, csh. The targeted gene (cs...

  15. Lineage-specific enhancers activate self-renewal genes in macrophages and embryonic stem cells.

    Science.gov (United States)

    Soucie, Erinn L; Weng, Ziming; Geirsdóttir, Laufey; Molawi, Kaaweh; Maurizio, Julien; Fenouil, Romain; Mossadegh-Keller, Noushine; Gimenez, Gregory; VanHille, Laurent; Beniazza, Meryam; Favret, Jeremy; Berruyer, Carole; Perrin, Pierre; Hacohen, Nir; Andrau, J-C; Ferrier, Pierre; Dubreuil, Patrice; Sidow, Arend; Sieweke, Michael H

    2016-02-12

    Differentiated macrophages can self-renew in tissues and expand long term in culture, but the gene regulatory mechanisms that accomplish self-renewal in the differentiated state have remained unknown. Here we show that in mice, the transcription factors MafB and c-Maf repress a macrophage-specific enhancer repertoire associated with a gene network that controls self-renewal. Single-cell analysis revealed that, in vivo, proliferating resident macrophages can access this network by transient down-regulation of Maf transcription factors. The network also controls embryonic stem cell self-renewal but is associated with distinct embryonic stem cell-specific enhancers. This indicates that distinct lineage-specific enhancer platforms regulate a shared network of genes that control self-renewal potential in both stem and mature cells. Copyright © 2016, American Association for the Advancement of Science.

  16. Microbial culturomics unravels the halophilic microbiota repertoire of table salt: description of Gracilibacillus massiliensis sp. nov.

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    Awa Diop

    2016-10-01

    Full Text Available Background: Microbial culturomics represents an ongoing revolution in the characterization of environmental and human microbiome. Methods: By using three media containing high salt concentration (100, 150, and 200 g/L, the halophilic microbial culturome of a commercial table salt was determined. Results: Eighteen species belonging to the Terrabacteria group were isolated including eight moderate halophilic and 10 halotolerant bacteria. Gracilibacillus massiliensis sp. nov., type strain Awa-1T (=CSUR P1441=DSM 29726, is a moderately halophilic gram-positive, non-spore-forming rod, and is motile by using a flagellum. Strain Awa-1T shows catalase activity but no oxidase activity. It is not only an aerobic bacterium but also able to grow in anaerobic and microaerophilic atmospheres. The draft genome of G. massiliensis is 4,207,226 bp long, composed of 13 scaffolds with 36.05% of G+C content. It contains 3,908 genes (3,839 protein-coding and 69 RNA genes. At least 1,983 (52% orthologous proteins were not shared with the closest phylogenetic species. Hundred twenty-six genes (3.3% were identified as ORFans. Conclusions: Microbial culturomics can dramatically improve the characterization of the food and environmental microbiota repertoire, deciphering new bacterial species and new genes. Further studies will clarify the geographic specificity and the putative role of these new microbes and their related functional genetic content in environment, health, and disease.

  17. Microbial culturomics unravels the halophilic microbiota repertoire of table salt: description of Gracilibacillus massiliensis sp. nov.

    Science.gov (United States)

    Diop, Awa; Khelaifia, Saber; Armstrong, Nicholas; Labas, Noémie; Fournier, Pierre-Edouard; Raoult, Didier; Million, Matthieu

    2016-01-01

    Microbial culturomics represents an ongoing revolution in the characterization of environmental and human microbiome. By using three media containing high salt concentration (100, 150, and 200 g/L), the halophilic microbial culturome of a commercial table salt was determined. Eighteen species belonging to the Terrabacteria group were isolated including eight moderate halophilic and 10 halotolerant bacteria. Gracilibacillus massiliensis sp. nov., type strain Awa-1 T (=CSUR P1441=DSM 29726), is a moderately halophilic gram-positive, non-spore-forming rod, and is motile by using a flagellum. Strain Awa-1 T shows catalase activity but no oxidase activity. It is not only an aerobic bacterium but also able to grow in anaerobic and microaerophilic atmospheres. The draft genome of G. massiliensis is 4,207,226 bp long, composed of 13 scaffolds with 36.05% of G+C content. It contains 3,908 genes (3,839 protein-coding and 69 RNA genes). At least 1,983 (52%) orthologous proteins were not shared with the closest phylogenetic species. Hundred twenty-six genes (3.3%) were identified as ORFans. Microbial culturomics can dramatically improve the characterization of the food and environmental microbiota repertoire, deciphering new bacterial species and new genes. Further studies will clarify the geographic specificity and the putative role of these new microbes and their related functional genetic content in environment, health, and disease.

  18. Development of a multiplex assay for genus- and species-specific detection of Phytophthora based on differences in mitochondrial gene order.

    Science.gov (United States)

    Bilodeau, Guillaume J; Martin, Frank N; Coffey, Michael D; Blomquist, Cheryl L

    2014-07-01

    A molecular diagnostic assay for Phytophthora spp. that is specific, sensitive, has both genus- and species-specific detection capabilities multiplexed, and can be used to systematically develop markers for detection of a wide range of species would facilitate research and regulatory efforts. To address this need, a marker system was developed based on the high copy sequences of the mitochondrial DNA utilizing gene orders that were highly conserved in the genus Phytophthora but different in the related genus Pythium and plants to reduce the importance of highly controlled annealing temperatures for specificity. An amplification primer pair designed from conserved regions of the atp9 and nad9 genes produced an amplicon of ≈340 bp specific for the Phytophthora spp. tested. The TaqMan probe for the genus-specific Phytophthora test was designed from a conserved portion of the atp9 gene whereas variable intergenic spacer sequences were used for designing the species-specific TaqMan probes. Specific probes were developed for 13 species and the P. citricola species complex. In silico analysis suggests that species-specific probes could be developed for at least 70 additional described and provisional species; the use of locked nucleic acids in TaqMan probes should expand this list. A second locus spanning three tRNAs (trnM-trnP-trnM) was also evaluated for genus-specific detection capabilities. At 206 bp, it was not as useful for systematic development of a broad range of species-specific probes as the larger 340-bp amplicon. All markers were validated against a test panel that included 87 Phytophthora spp., 14 provisional Phytophthora spp., 29 Pythium spp., 1 Phytopythium sp., and 39 plant species. Species-specific probes were validated further against a range of geographically diverse isolates to ensure uniformity of detection at an intraspecific level, as well as with other species having high levels of sequence similarity to ensure specificity. Both diagnostic

  19. Hepatocyte specific expression of human cloned genes

    Energy Technology Data Exchange (ETDEWEB)

    Cortese, R

    1986-01-01

    A large number of proteins are specifically synthesized in the hepatocyte. Only the adult liver expresses the complete repertoire of functions which are required at various stages during development. There is therefore a complex series of regulatory mechanisms responsible for the maintenance of the differentiated state and for the developmental and physiological variations in the pattern of gene expression. Human hepatoma cell lines HepG2 and Hep3B display a pattern of gene expression similar to adult and fetal liver, respectively; in contrast, cultured fibroblasts or HeLa cells do not express most of the liver specific genes. They have used these cell lines for transfection experiments with cloned human liver specific genes. DNA segments coding for alpha1-antitrypsin and retinol binding protein (two proteins synthesized both in fetal and adult liver) are expressed in the hepatoma cell lines HepG2 and Hep3B, but not in HeLa cells or fibroblasts. A DNA segment coding for haptoglobin (a protein synthesized only after birth) is only expressed in the hepatoma cell line HepG2 but not in Hep3B nor in non hepatic cell lines. The information for tissue specific expression is located in the 5' flanking region of all three genes. In vivo competition experiments show that these DNA segments bind to a common, apparently limiting, transacting factor. Conventional techniques (Bal deletions, site directed mutagenesis, etc.) have been used to precisely identify the DNA sequences responsible for these effects. The emerging picture is complex: they have identified multiple, separate transcriptional signals, essential for maximal promoter activation and tissue specific expression. Some of these signals show a negative effect on transcription in fibroblast cell lines.

  20. Quantitative Analysis of Repertoire-Scale Immunoglobulin Properties in Vaccine-Induced B-Cell Responses

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    Ilja V. Khavrutskii

    2017-08-01

    Full Text Available Recent advances in the next-generation sequencing of B-cell receptors (BCRs enable the characterization of humoral responses at a repertoire-wide scale and provide the capability for identifying unique features of immune repertoires in response to disease, vaccination, or infection. Immunosequencing now readily generates 103–105 sequences per sample; however, statistical analysis of these repertoires is challenging because of the high genetic diversity of BCRs and the elaborate clonal relationships among them. To date, most immunosequencing analyses have focused on reporting qualitative trends in immunoglobulin (Ig properties, such as usage or somatic hypermutation (SHM percentage of the Ig heavy chain variable (IGHV gene segment family, and on reducing complex Ig property distributions to simple summary statistics. However, because Ig properties are typically not normally distributed, any approach that fails to assess the distribution as a whole may be inadequate in (1 properly assessing the statistical significance of repertoire differences, (2 identifying how two repertoires differ, and (3 determining appropriate confidence intervals for assessing the size of the differences and their potential biological relevance. To address these issues, we have developed a technique that uses Wilcox’ robust statistics toolbox to identify statistically significant vaccine-specific differences between Ig repertoire properties. The advantage of this technique is that it can determine not only whether but also where the distributions differ, even when the Ig repertoire properties are non-normally distributed. We used this technique to characterize murine germinal center (GC B-cell repertoires in response to a complex Ebola virus-like particle (eVLP vaccine candidate with known protective efficacy. The eVLP-mediated GC B-cell responses were highly diverse, consisting of thousands of clonotypes. Despite this staggering diversity, we identified statistically

  1. The effects of a partitioned var gene repertoire of Plasmodium falciparum on antigenic diversity and the acquisition of clinical immunity

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    Arinaminpathy Nimalan

    2008-01-01

    Full Text Available Abstract Background The human malaria parasite Plasmodium falciparum exploits antigenic diversity and within-host antigenic variation to evade the host's immune system. Of particular importance are the highly polymorphic var genes that encode the family of cell surface antigens PfEMP1 (Plasmodium falciparum Erythrocyte Membrane Protein 1. It has recently been shown that in spite of their extreme diversity, however, these genes fall into distinct groups according to chromosomal location or sequence similarity, and that recombination may be confined within these groups. Methods This study presents a mathematical analysis of how recombination hierarchies affect diversity, and, by using simple stochastic simulations, investigates how intra- and inter-genic diversity influence the rate at which individuals acquire clinical immunity. Results The analysis demonstrates that the partitioning of the var gene repertoire has a limiting effect on the total diversity attainable through recombination and that the limiting effect is strongly influenced by the respective sizes of each of the partitions. Furthermore, by associating expression of one of the groups with severe malaria it is demonstrated how a small number of infections can be sufficient to protect against disease despite a seemingly limitless number of possible non-identical repertoires. Conclusion Recombination hierarchies within the var gene repertoire of P. falciparum have a severe effect on strain diversity and the process of acquiring immunity against clinical malaria. Future studies will show how the existence of these recombining groups can offer an evolutionary advantage in spite of their restriction on diversity.

  2. Species-independent MicroRNA Gene Discovery

    KAUST Repository

    Kamanu, Timothy K.

    2012-12-01

    RNA genes are not only species-specific but may also be DNA strand-specific and chromosome-specific; the genomic distribution of miRNA genes is conserved at the chromosomal level across species; miRNA are conserved; More than one miRNA with different regulatory targets can be excised from one miRNA gene; Repeat-related miRNA and miRNA genes with palindromic sequences may be the largest subclass of miRNA class that have eluded detection by most computational and experimental methods.

  3. Massively Parallel RNA Sequencing Identifies a Complex Immune Gene Repertoire in the lophotrochozoan Mytilus edulis

    Science.gov (United States)

    Philipp, Eva E. R.; Kraemer, Lars; Melzner, Frank; Poustka, Albert J.; Thieme, Sebastian; Findeisen, Ulrike; Schreiber, Stefan; Rosenstiel, Philip

    2012-01-01

    The marine mussel Mytilus edulis and its closely related sister species are distributed world-wide and play an important role in coastal ecology and economy. The diversification in different species and their hybrids, broad ecological distribution, as well as the filter feeding mode of life has made this genus an attractive model to investigate physiological and molecular adaptations and responses to various biotic and abiotic environmental factors. In the present study we investigated the immune system of Mytilus, which may contribute to the ecological plasticity of this species. We generated a large Mytilus transcriptome database from different tissues of immune challenged and stress treated individuals from the Baltic Sea using 454 pyrosequencing. Phylogenetic comparison of orthologous groups of 23 species demonstrated the basal position of lophotrochozoans within protostomes. The investigation of immune related transcripts revealed a complex repertoire of innate recognition receptors and downstream pathway members including transcripts for 27 toll-like receptors and 524 C1q domain containing transcripts. NOD-like receptors on the other hand were absent. We also found evidence for sophisticated TNF, autophagy and apoptosis systems as well as for cytokines. Gill tissue and hemocytes showed highest expression of putative immune related contigs and are promising tissues for further functional studies. Our results partly contrast with findings of a less complex immune repertoire in ecdysozoan and other lophotrochozoan protostomes. We show that bivalves are interesting candidates to investigate the evolution of the immune system from basal metazoans to deuterostomes and protostomes and provide a basis for future molecular work directed to immune system functioning in Mytilus. PMID:22448234

  4. Teleost Fish-Specific Preferential Retention of Pigmentation Gene-Containing Families After Whole Genome Duplications in Vertebrates

    Science.gov (United States)

    Lorin, Thibault; Brunet, Frédéric G.; Laudet, Vincent; Volff, Jean-Nicolas

    2018-01-01

    Vertebrate pigmentation is a highly diverse trait mainly determined by neural crest cell derivatives. It has been suggested that two rounds (1R/2R) of whole-genome duplications (WGDs) at the basis of vertebrates allowed changes in gene regulation associated with neural crest evolution. Subsequently, the teleost fish lineage experienced other WGDs, including the teleost-specific Ts3R before teleost radiation and the more recent Ss4R at the basis of salmonids. As the teleost lineage harbors the highest number of pigment cell types and pigmentation diversity in vertebrates, WGDs might have contributed to the evolution and diversification of the pigmentation gene repertoire in teleosts. We have compared the impact of the basal vertebrate 1R/2R duplications with that of the teleost-specific Ts3R and salmonid-specific Ss4R WGDs on 181 gene families containing genes involved in pigmentation. We show that pigmentation genes (PGs) have been globally more frequently retained as duplicates than other genes after Ts3R and Ss4R but not after the early 1R/2R. This is also true for non-pigmentary paralogs of PGs, suggesting that the function in pigmentation is not the sole key driver of gene retention after WGDs. On the long-term, specific categories of PGs have been repeatedly preferentially retained after ancient 1R/2R and Ts3R WGDs, possibly linked to the molecular nature of their proteins (e.g., DNA binding transcriptional regulators) and their central position in protein-protein interaction networks. Taken together, our results support a major role of WGDs in the diversification of the pigmentation gene repertoire in the teleost lineage, with a possible link with the diversity of pigment cell lineages observed in these animals compared to other vertebrates. PMID:29599177

  5. Use of species-specific PCR for the identification of 10 sea cucumber species

    Science.gov (United States)

    Wen, Jing; Zeng, Ling

    2014-11-01

    We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species. Ten reverse species-specific primers designed from the 16S rRNA gene, in combination with one forward universal primer, generated PCR fragments of ca. 270 bp length for each species. The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species. Amplification was observed in specific species only. The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber, and was proven to be a useful, rapid, and low-cost technique to identify the origin of the sea cucumber product.

  6. The porcine antibody repertoire: Variations on the textbook theme

    Directory of Open Access Journals (Sweden)

    John eButler

    2012-06-01

    Full Text Available The genes encoding the heavy and light chains of swine antibodies are organized in the same manner as in other eutherian mammals. There are ~ 30 VH genes, two functional DH genes and one functional JH gene. There are 14-60 V genes and 5 J segments, >22V genes and at least four JC cassettes. The heavy chain constant regions encode the same repertoire of isotypes common to other eutherian mammals. The piglet models offers advantage over rodent models since the fetal repertoire develops without maternal influences and the precocial nature of their multiple offspring allows the experimenter to control the influences of environmental and maternal factors on repertoire development postnatally. B cell lymphogenesis in swine begins in the fetal yolk sac at 20 days of gestation (DG, moves to the fetal liver at 30 DG and eventually to the bone marrow which dominates until birth (114 DG and to at least 5 weeks postpartum. There is no evidence that the ileal Peyers patches are a site of B cell lymphogenesis or are required for B cell maintenance. Unlike rodents and humans, light chain rearrangement begins first in the lambda locus; kappa rearrangements are not seen until late gestation.Dissimilar to lab rodents and more in the direction of the rabbit, swine utilize a small number of VH genes to form >90% of their pre-immune repertoire. Diversification in response to environmental antigen does not alter this pattern and is achieved by somatic hypermutation (SHM of the same small number of VH genes. The situation for light chains is less-well studied, but certain V and J and V and J are dominant in transcripts. The transcribed and secreted pre-immune antibodies of the fetus include mainly IgM, IgA and IgG3; this last isotype may provide a type of first responder mucosal immunity. Development of functional adaptive immunity is dependent on bacterial PAMPs or PAMPs provided by viral infections, indicating the importance of innate

  7. Environmental genomics of "Haloquadratum walsbyi" in a saltern crystallizer indicates a large pool of accessory genes in an otherwise coherent species

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    Bolhuis Henk

    2006-07-01

    Full Text Available Abstract Background Mature saturated brine (crystallizers communities are largely dominated (>80% of cells by the square halophilic archaeon "Haloquadratum walsbyi". The recent cultivation of the strain HBSQ001 and thesequencing of its genome allows comparison with the metagenome of this taxonomically simplified environment. Similar studies carried out in other extreme environments have revealed very little diversity in gene content among the cell lineages present. Results The metagenome of the microbial community of a crystallizer pond has been analyzed by end sequencing a 2000 clone fosmid library and comparing the sequences obtained with the genome sequence of "Haloquadratum walsbyi". The genome of the sequenced strain was retrieved nearly complete within this environmental DNA library. However, many ORF's that could be ascribed to the "Haloquadratum" metapopulation by common genome characteristics or scaffolding to the strain genome were not present in the specific sequenced isolate. Particularly, three regions of the sequenced genome were associated with multiple rearrangements and the presence of different genes from the metapopulation. Many transposition and phage related genes were found within this pool which, together with the associated atypical GC content in these areas, supports lateral gene transfer mediated by these elements as the most probable genetic cause of this variability. Additionally, these sequences were highly enriched in putative regulatory and signal transduction functions. Conclusion These results point to a large pan-genome (total gene repertoire of the genus/species even in this highly specialized extremophile and at a single geographic location. The extensive gene repertoire is what might be expected of a population that exploits a diverse nutrient pool, resulting from the degradation of biomass produced at lower salinities.

  8. Specific duplication and dorsoventrally asymmetric expression patterns of Cycloidea-like genes in zygomorphic species of Ranunculaceae.

    Science.gov (United States)

    Jabbour, Florian; Cossard, Guillaume; Le Guilloux, Martine; Sannier, Julie; Nadot, Sophie; Damerval, Catherine

    2014-01-01

    Floral bilateral symmetry (zygomorphy) has evolved several times independently in angiosperms from radially symmetrical (actinomorphic) ancestral states. Homologs of the Antirrhinum majus Cycloidea gene (Cyc) have been shown to control floral symmetry in diverse groups in core eudicots. In the basal eudicot family Ranunculaceae, there is a single evolutionary transition from actinomorphy to zygomorphy in the stem lineage of the tribe Delphinieae. We characterized Cyc homologs in 18 genera of Ranunculaceae, including the four genera of Delphinieae, in a sampling that represents the floral morphological diversity of this tribe, and reconstructed the evolutionary history of this gene family in Ranunculaceae. Within each of the two RanaCyL (Ranunculaceae Cycloidea-like) lineages previously identified, an additional duplication possibly predating the emergence of the Delphinieae was found, resulting in up to four gene copies in zygomorphic species. Expression analyses indicate that the RanaCyL paralogs are expressed early in floral buds and that the duration of their expression varies between species and paralog class. At most one RanaCyL paralog was expressed during the late stages of floral development in the actinomorphic species studied whereas all paralogs from the zygomorphic species were expressed, composing a species-specific identity code for perianth organs. The contrasted asymmetric patterns of expression observed in the two zygomorphic species is discussed in relation to their distinct perianth architecture.

  9. Specific duplication and dorsoventrally asymmetric expression patterns of Cycloidea-like genes in zygomorphic species of Ranunculaceae.

    Directory of Open Access Journals (Sweden)

    Florian Jabbour

    Full Text Available Floral bilateral symmetry (zygomorphy has evolved several times independently in angiosperms from radially symmetrical (actinomorphic ancestral states. Homologs of the Antirrhinum majus Cycloidea gene (Cyc have been shown to control floral symmetry in diverse groups in core eudicots. In the basal eudicot family Ranunculaceae, there is a single evolutionary transition from actinomorphy to zygomorphy in the stem lineage of the tribe Delphinieae. We characterized Cyc homologs in 18 genera of Ranunculaceae, including the four genera of Delphinieae, in a sampling that represents the floral morphological diversity of this tribe, and reconstructed the evolutionary history of this gene family in Ranunculaceae. Within each of the two RanaCyL (Ranunculaceae Cycloidea-like lineages previously identified, an additional duplication possibly predating the emergence of the Delphinieae was found, resulting in up to four gene copies in zygomorphic species. Expression analyses indicate that the RanaCyL paralogs are expressed early in floral buds and that the duration of their expression varies between species and paralog class. At most one RanaCyL paralog was expressed during the late stages of floral development in the actinomorphic species studied whereas all paralogs from the zygomorphic species were expressed, composing a species-specific identity code for perianth organs. The contrasted asymmetric patterns of expression observed in the two zygomorphic species is discussed in relation to their distinct perianth architecture.

  10. Phylogeography of var gene repertoires reveals fine-scale geospatial clustering of Plasmodium falciparum populations in a highly endemic area.

    Science.gov (United States)

    Tessema, Sofonias K; Monk, Stephanie L; Schultz, Mark B; Tavul, Livingstone; Reeder, John C; Siba, Peter M; Mueller, Ivo; Barry, Alyssa E

    2015-01-01

    Plasmodium falciparum malaria is a major global health problem that is being targeted for progressive elimination. Knowledge of local disease transmission patterns in endemic countries is critical to these elimination efforts. To investigate fine-scale patterns of malaria transmission, we have compared repertoires of rapidly evolving var genes in a highly endemic area. A total of 3680 high-quality DBLα-sequences were obtained from 68 P. falciparum isolates from ten villages spread over two distinct catchment areas on the north coast of Papua New Guinea (PNG). Modelling of the extent of var gene diversity in the two parasite populations predicts more than twice as many var gene alleles circulating within each catchment (Mugil = 906; Wosera = 1094) than previously recognized in PNG (Amele = 369). In addition, there were limited levels of var gene sharing between populations, consistent with local parasite population structure. Phylogeographic analyses demonstrate that while neutrally evolving microsatellite markers identified population structure only at the catchment level, var gene repertoires reveal further fine-scale geospatial clustering of parasite isolates. The clustering of parasite isolates by village in Mugil, but not in Wosera was consistent with the physical and cultural isolation of the human populations in the two catchments. The study highlights the microheterogeneity of P. falciparum transmission in highly endemic areas and demonstrates the potential of var genes as markers of local patterns of parasite population structure. © 2014 John Wiley & Sons Ltd.

  11. Systems Analysis Reveals High Genetic and Antigen-Driven Predetermination of Antibody Repertoires throughout B Cell Development

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    Victor Greiff

    2017-05-01

    Full Text Available Antibody repertoire diversity and plasticity is crucial for broad protective immunity. Repertoires change in size and diversity across multiple B cell developmental stages and in response to antigen exposure. However, we still lack fundamental quantitative understanding of the extent to which repertoire diversity is predetermined. Therefore, we implemented a systems immunology framework for quantifying repertoire predetermination on three distinct levels: (1 B cell development (pre-B cell, naive B cell, plasma cell, (2 antigen exposure (three structurally different proteins, and (3 four antibody repertoire components (V-gene usage, clonal expansion, clonal diversity, repertoire size extracted from antibody repertoire sequencing data (400 million reads. Across all three levels, we detected a dynamic balance of high genetic (e.g., >90% for V-gene usage and clonal expansion in naive B cells and antigen-driven (e.g., 40% for clonal diversity in plasma cells predetermination and stochastic variation. Our study has implications for the prediction and manipulation of humoral immunity.

  12. Evolutionary acquisition of promoter-associated non-coding RNA (pancRNA) repertoires diversifies species-dependent gene activation mechanisms in mammals

    OpenAIRE

    Uesaka, Masahiro; Agata, Kiyokazu; Oishi, Takao; Nakashima, Kinichi; Imamura, Takuya

    2017-01-01

    Background Recent transcriptome analyses have shown that long non-coding RNAs (ncRNAs) play extensive roles in transcriptional regulation. In particular, we have reported that promoter-associated ncRNAs (pancRNAs) activate the partner gene expression via local epigenetic changes. Results Here, we identify thousands of genes under pancRNA-mediated transcriptional activation in five mammalian species in common. In the mouse, 1) pancRNA-partnered genes confined their expression pattern to certai...

  13. Species specificity in major urinary proteins by parallel evolution.

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    Darren W Logan

    Full Text Available Species-specific chemosignals, pheromones, regulate social behaviors such as aggression, mating, pup-suckling, territory establishment, and dominance. The identity of these cues remains mostly undetermined and few mammalian pheromones have been identified. Genetically-encoded pheromones are expected to exhibit several different mechanisms for coding 1 diversity, to enable the signaling of multiple behaviors, 2 dynamic regulation, to indicate age and dominance, and 3 species-specificity. Recently, the major urinary proteins (Mups have been shown to function themselves as genetically-encoded pheromones to regulate species-specific behavior. Mups are multiple highly related proteins expressed in combinatorial patterns that differ between individuals, gender, and age; which are sufficient to fulfill the first two criteria. We have now characterized and fully annotated the mouse Mup gene content in detail. This has enabled us to further analyze the extent of Mup coding diversity and determine their potential to encode species-specific cues.Our results show that the mouse Mup gene cluster is composed of two subgroups: an older, more divergent class of genes and pseudogenes, and a second class with high sequence identity formed by recent sequential duplications of a single gene/pseudogene pair. Previous work suggests that truncated Mup pseudogenes may encode a family of functional hexapeptides with the potential for pheromone activity. Sequence comparison, however, reveals that they have limited coding potential. Similar analyses of nine other completed genomes find Mup gene expansions in divergent lineages, including those of rat, horse and grey mouse lemur, occurring independently from a single ancestral Mup present in other placental mammals. Our findings illustrate that increasing genomic complexity of the Mup gene family is not evolutionarily isolated, but is instead a recurring mechanism of generating coding diversity consistent with a species-specific

  14. Phylogenomic analysis of vertebrate thrombospondins reveals fish-specific paralogues, ancestral gene relationships and a tetrapod innovation

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    Adams Josephine C

    2006-04-01

    Full Text Available Abstract Background Thrombospondins (TSPs are evolutionarily-conserved, extracellular, calcium-binding glycoproteins with important roles in cell-extracellular matrix interactions, angiogenesis, synaptogenesis and connective tissue organisation. Five TSPs, designated TSP-1 through TSP-5, are encoded in the human genome. All but one have known roles in acquired or inherited human diseases. To further understand the roles of TSPs in human physiology and pathology, it would be advantageous to extend the repertoire of relevant vertebrate models. In general the zebrafish is proving an excellent model organism for vertebrate biology, therefore we set out to evaluate the status of TSPs in zebrafish and two species of pufferfish. Results We identified by bioinformatics that three fish species encode larger numbers of TSPs than vertebrates, yet all these sequences group as homologues of TSP-1 to -4. By phylogenomic analysis of neighboring genes, we uncovered that, in fish, a TSP-4-like sequence is encoded from the gene corresponding to the tetrapod TSP-5 gene. Thus, all TSP genes show conservation of synteny between fish and tetrapods. In the human genome, the TSP-1, TSP-3, TSP-4 and TSP-5 genes lie within paralogous regions that provide insight into the ancestral genomic context of vertebrate TSPs. Conclusion A new model for TSP evolution in vertebrates is presented. The TSP-5 protein sequence has evolved rapidly from a TSP-4-like sequence as an innovation in the tetrapod lineage. TSP biology in fish is complicated by the presence of additional lineage- and species-specific TSP paralogues. These novel results give deeper insight into the evolution of TSPs in vertebrates and open new directions for understanding the physiological and pathological roles of TSP-4 and TSP-5 in humans.

  15. Employment of Near Full-Length Ribosome Gene TA-Cloning and Primer-Blast to Detect Multiple Species in a Natural Complex Microbial Community Using Species-Specific Primers Designed with Their Genome Sequences.

    Science.gov (United States)

    Zhang, Huimin; He, Hongkui; Yu, Xiujuan; Xu, Zhaohui; Zhang, Zhizhou

    2016-11-01

    It remains an unsolved problem to quantify a natural microbial community by rapidly and conveniently measuring multiple species with functional significance. Most widely used high throughput next-generation sequencing methods can only generate information mainly for genus-level taxonomic identification and quantification, and detection of multiple species in a complex microbial community is still heavily dependent on approaches based on near full-length ribosome RNA gene or genome sequence information. In this study, we used near full-length rRNA gene library sequencing plus Primer-Blast to design species-specific primers based on whole microbial genome sequences. The primers were intended to be specific at the species level within relevant microbial communities, i.e., a defined genomics background. The primers were tested with samples collected from the Daqu (also called fermentation starters) and pit mud of a traditional Chinese liquor production plant. Sixteen pairs of primers were found to be suitable for identification of individual species. Among them, seven pairs were chosen to measure the abundance of microbial species through quantitative PCR. The combination of near full-length ribosome RNA gene library sequencing and Primer-Blast may represent a broadly useful protocol to quantify multiple species in complex microbial population samples with species-specific primers.

  16. Expanding the Repertoire of Optogenetically Targeted Cells with an Enhanced Gene Expression System

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    Kenji F. Tanaka

    2012-08-01

    Full Text Available Optogenetics has been enthusiastically pursued in recent neuroscience research, and the causal relationship between neural activity and behavior is becoming ever more accessible. Here, we established knockin-mediated enhanced gene expression by improved tetracycline-controlled gene induction (KENGE-tet and succeeded in generating transgenic mice expressing a highly light-sensitive channelrhodopsin-2 mutant at levels sufficient to drive the activities of multiple cell types. This method requires two lines of mice: one that controls the pattern of expression and another that determines the protein to be produced. The generation of new lines of either type readily expands the repertoire to choose from. In addition to neurons, we were able to manipulate the activity of nonexcitable glial cells in vivo. This shows that our system is applicable not only to neuroscience but also to any biomedical study that requires understanding of how the activity of a selected population of cells propagates through the intricate organic systems.

  17. The mimetic repertoire of the spotted bowerbird Ptilonorhynchus maculatus

    Science.gov (United States)

    Kelley, Laura A.; Healy, Susan D.

    2011-06-01

    Although vocal mimicry in songbirds is well documented, little is known about the function of such mimicry. One possibility is that the mimic produces the vocalisations of predatory or aggressive species to deter potential predators or competitors. Alternatively, these sounds may be learned in error as a result of their acoustic properties such as structural simplicity. We determined the mimetic repertoires of a population of male spotted bowerbirds Ptilonorhynchus maculatus, a species that mimics predatory and aggressive species. Although male mimetic repertoires contained an overabundance of vocalisations produced by species that were generally aggressive, there was also a marked prevalence of mimicry of sounds that are associated with alarm such as predator calls, alarm calls and mobbing calls, irrespective of whether the species being mimicked was aggressive or not. We propose that it may be the alarming context in which these sounds are first heard that may lead both to their acquisition and to their later reproduction. We suggest that enhanced learning capability during acute stress may explain vocal mimicry in many species that mimic sounds associated with alarm.

  18. Genomic organization and evolution of the Atlantic salmon hemoglobin repertoire

    Directory of Open Access Journals (Sweden)

    Phillips Ruth B

    2010-10-01

    Full Text Available Abstract Background The genomes of salmonids are considered pseudo-tetraploid undergoing reversion to a stable diploid state. Given the genome duplication and extensive biological data available for salmonids, they are excellent model organisms for studying comparative genomics, evolutionary processes, fates of duplicated genes and the genetic and physiological processes associated with complex behavioral phenotypes. The evolution of the tetrapod hemoglobin genes is well studied; however, little is known about the genomic organization and evolution of teleost hemoglobin genes, particularly those of salmonids. The Atlantic salmon serves as a representative salmonid species for genomics studies. Given the well documented role of hemoglobin in adaptation to varied environmental conditions as well as its use as a model protein for evolutionary analyses, an understanding of the genomic structure and organization of the Atlantic salmon α and β hemoglobin genes is of great interest. Results We identified four bacterial artificial chromosomes (BACs comprising two hemoglobin gene clusters spanning the entire α and β hemoglobin gene repertoire of the Atlantic salmon genome. Their chromosomal locations were established using fluorescence in situ hybridization (FISH analysis and linkage mapping, demonstrating that the two clusters are located on separate chromosomes. The BACs were sequenced and assembled into scaffolds, which were annotated for putatively functional and pseudogenized hemoglobin-like genes. This revealed that the tail-to-tail organization and alternating pattern of the α and β hemoglobin genes are well conserved in both clusters, as well as that the Atlantic salmon genome houses substantially more hemoglobin genes, including non-Bohr β globin genes, than the genomes of other teleosts that have been sequenced. Conclusions We suggest that the most parsimonious evolutionary path leading to the present organization of the Atlantic salmon

  19. Genomic organization and evolution of the Atlantic salmon hemoglobin repertoire

    Science.gov (United States)

    2010-01-01

    Background The genomes of salmonids are considered pseudo-tetraploid undergoing reversion to a stable diploid state. Given the genome duplication and extensive biological data available for salmonids, they are excellent model organisms for studying comparative genomics, evolutionary processes, fates of duplicated genes and the genetic and physiological processes associated with complex behavioral phenotypes. The evolution of the tetrapod hemoglobin genes is well studied; however, little is known about the genomic organization and evolution of teleost hemoglobin genes, particularly those of salmonids. The Atlantic salmon serves as a representative salmonid species for genomics studies. Given the well documented role of hemoglobin in adaptation to varied environmental conditions as well as its use as a model protein for evolutionary analyses, an understanding of the genomic structure and organization of the Atlantic salmon α and β hemoglobin genes is of great interest. Results We identified four bacterial artificial chromosomes (BACs) comprising two hemoglobin gene clusters spanning the entire α and β hemoglobin gene repertoire of the Atlantic salmon genome. Their chromosomal locations were established using fluorescence in situ hybridization (FISH) analysis and linkage mapping, demonstrating that the two clusters are located on separate chromosomes. The BACs were sequenced and assembled into scaffolds, which were annotated for putatively functional and pseudogenized hemoglobin-like genes. This revealed that the tail-to-tail organization and alternating pattern of the α and β hemoglobin genes are well conserved in both clusters, as well as that the Atlantic salmon genome houses substantially more hemoglobin genes, including non-Bohr β globin genes, than the genomes of other teleosts that have been sequenced. Conclusions We suggest that the most parsimonious evolutionary path leading to the present organization of the Atlantic salmon hemoglobin genes involves

  20. Germline V repertoires: Origin, maintenance, diversification.

    Science.gov (United States)

    Steele, E J; Lindley, R A

    2018-06-01

    In our view, Melvin Cohn (Scand J Immunol. 2018;87:e12640) has set out the logical guidelines towards a resolution of the very real enigma of the selectability of vertebrate germline Ig V repertoires under the current evolutionary paradigm…" A somatically derived repertoire scrambles this (germline VL + VH) substrate so that its specificities are lost, making it un-selectable in the germline. Consequently, evolution faced an incompatibility." It is argued here in Reply that a reverse transcriptase-based soma-to-germline process (S->G) targeting germline V segment arrays goes some considerable way to resolving fundamental contradictions on the origin, maintenance and then real-time adaptive diversification of these limited sets of V segments encoded within various V repertoire arrays. © 2018 The Foundation for the Scandinavian Journal of Immunology.

  1. Antibody repertoires in humanized NOD-scid-IL2Rγ(null mice and human B cells reveals human-like diversification and tolerance checkpoints in the mouse.

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    Gregory C Ippolito

    Full Text Available Immunodeficient mice reconstituted with human hematopoietic stem cells enable the in vivo study of human hematopoiesis. In particular, NOD-scid-IL2Rγ(null engrafted mice have been shown to have reasonable levels of T and B cell repopulation and can mount T-cell dependent responses; however, antigen-specific B-cell responses in this model are generally poor. We explored whether developmental defects in the immunoglobulin gene repertoire might be partly responsible for the low level of antibody responses in this model. Roche 454 sequencing was used to obtain over 685,000 reads from cDNA encoding immunoglobulin heavy (IGH and light (IGK and IGL genes isolated from immature, naïve, or total splenic B cells in engrafted NOD-scid-IL2Rγ(null mice, and compared with over 940,000 reads from peripheral B cells of two healthy volunteers. We find that while naïve B-cell repertoires in humanized mice are chiefly indistinguishable from those in human blood B cells, and display highly correlated patterns of immunoglobulin gene segment use, the complementarity-determining region H3 (CDR-H3 repertoires are nevertheless extremely diverse and are specific for each individual. Despite this diversity, preferential D(H-J(H pairings repeatedly occur within the CDR-H3 interval that are strikingly similar across all repertoires examined, implying a genetic constraint imposed on repertoire generation. Moreover, CDR-H3 length, charged amino-acid content, and hydropathy are indistinguishable between humans and humanized mice, with no evidence of global autoimmune signatures. Importantly, however, a statistically greater usage of the inherently autoreactive IGHV4-34 and IGKV4-1 genes was observed in the newly formed immature B cells relative to naïve B or total splenic B cells in the humanized mice, a finding consistent with the deletion of autoreactive B cells in humans. Overall, our results provide evidence that key features of the primary repertoire are shaped by

  2. The genome sequence of the commercially cultivated mushroom Agrocybe aegerita reveals a conserved repertoire of fruiting-related genes and a versatile suite of biopolymer-degrading enzymes.

    Science.gov (United States)

    Gupta, Deepak K; Rühl, Martin; Mishra, Bagdevi; Kleofas, Vanessa; Hofrichter, Martin; Herzog, Robert; Pecyna, Marek J; Sharma, Rahul; Kellner, Harald; Hennicke, Florian; Thines, Marco

    2018-01-15

    Agrocybe aegerita is an agaricomycete fungus with typical mushroom features, which is commercially cultivated for its culinary use. In nature, it is a saprotrophic or facultative pathogenic fungus causing a white-rot of hardwood in forests of warm and mild climate. The ease of cultivation and fructification on solidified media as well as its archetypal mushroom fruit body morphology render A. aegerita a well-suited model for investigating mushroom developmental biology. Here, the genome of the species is reported and analysed with respect to carbohydrate active genes and genes known to play a role during fruit body formation. In terms of fruit body development, our analyses revealed a conserved repertoire of fruiting-related genes, which corresponds well to the archetypal fruit body morphology of this mushroom. For some genes involved in fruit body formation, paralogisation was observed, but not all fruit body maturation-associated genes known from other agaricomycetes seem to be conserved in the genome sequence of A. aegerita. In terms of lytic enzymes, our analyses suggest a versatile arsenal of biopolymer-degrading enzymes that likely account for the flexible life style of this species. Regarding the amount of genes encoding CAZymes relevant for lignin degradation, A. aegerita shows more similarity to white-rot fungi than to litter decomposers, including 18 genes coding for unspecific peroxygenases and three dye-decolourising peroxidase genes expanding its lignocellulolytic machinery. The genome resource will be useful for developing strategies towards genetic manipulation of A. aegerita, which will subsequently allow functional genetics approaches to elucidate fundamentals of fruiting and vegetative growth including lignocellulolysis.

  3. Automatic generation of gene finders for eukaryotic species

    DEFF Research Database (Denmark)

    Terkelsen, Kasper Munch; Krogh, A.

    2006-01-01

    and quality of reliable gene annotation grows. Results We present a procedure, Agene, that automatically generates a species-specific gene predictor from a set of reliable mRNA sequences and a genome. We apply a Hidden Markov model (HMM) that implements explicit length distribution modelling for all gene......Background The number of sequenced eukaryotic genomes is rapidly increasing. This means that over time it will be hard to keep supplying customised gene finders for each genome. This calls for procedures to automatically generate species-specific gene finders and to re-train them as the quantity...... structure blocks using acyclic discrete phase type distributions. The state structure of the each HMM is generated dynamically from an array of sub-models to include only gene features represented in the training set. Conclusion Acyclic discrete phase type distributions are well suited to model sequence...

  4. Variability and repertoire size of T-cell receptor V alpha gene segments.

    Science.gov (United States)

    Becker, D M; Pattern, P; Chien, Y; Yokota, T; Eshhar, Z; Giedlin, M; Gascoigne, N R; Goodnow, C; Wolf, R; Arai, K

    The immune system of higher organisms is composed largely of two distinct cell types, B lymphocytes and T lymphocytes, each of which is independently capable of recognizing an enormous number of distinct entities through their antigen receptors; surface immunoglobulin in the case of the former, and the T-cell receptor (TCR) in the case of the latter. In both cell types, the genes encoding the antigen receptors consist of multiple gene segments which recombine during maturation to produce many possible peptides. One striking difference between B- and T-cell recognition that has not yet been resolved by the structural data is the fact that T cells generally require a major histocompatibility determinant together with an antigen whereas, in most cases, antibodies recognize antigen alone. Recently, we and others have found that a series of TCR V beta gene sequences show conservation of many of the same residues that are conserved between heavy- and light-chain immunoglobulin V regions, and these V beta sequences are predicted to have an immunoglobulin-like secondary structure. To extend these studies, we have isolated and sequenced eight additional alpha-chain complementary cDNA clones and compared them with published sequences. Analyses of these sequences, reported here, indicate that V alpha regions have many of the characteristics of V beta gene segments but differ in that they almost always occur as cross-hybridizing gene families. We conclude that there may be very different selective pressures operating on V alpha and V beta sequences and that the V alpha repertoire may be considerably larger than that of V beta.

  5. Hybridization-based antibody cDNA recovery for the production of recombinant antibodies identified by repertoire sequencing.

    Science.gov (United States)

    Valdés-Alemán, Javier; Téllez-Sosa, Juan; Ovilla-Muñoz, Marbella; Godoy-Lozano, Elizabeth; Velázquez-Ramírez, Daniel; Valdovinos-Torres, Humberto; Gómez-Barreto, Rosa E; Martinez-Barnetche, Jesús

    2014-01-01

    High-throughput sequencing of the antibody repertoire is enabling a thorough analysis of B cell diversity and clonal selection, which may improve the novel antibody discovery process. Theoretically, an adequate bioinformatic analysis could allow identification of candidate antigen-specific antibodies, requiring their recombinant production for experimental validation of their specificity. Gene synthesis is commonly used for the generation of recombinant antibodies identified in silico. Novel strategies that bypass gene synthesis could offer more accessible antibody identification and validation alternatives. We developed a hybridization-based recovery strategy that targets the complementarity-determining region 3 (CDRH3) for the enrichment of cDNA of candidate antigen-specific antibody sequences. Ten clonal groups of interest were identified through bioinformatic analysis of the heavy chain antibody repertoire of mice immunized with hen egg white lysozyme (HEL). cDNA from eight of the targeted clonal groups was recovered efficiently, leading to the generation of recombinant antibodies. One representative heavy chain sequence from each clonal group recovered was paired with previously reported anti-HEL light chains to generate full antibodies, later tested for HEL-binding capacity. The recovery process proposed represents a simple and scalable molecular strategy that could enhance antibody identification and specificity assessment, enabling a more cost-efficient generation of recombinant antibodies.

  6. Frequency and genetic characterization of V(DD)J recombinants in the human peripheral blood antibody repertoire.

    Science.gov (United States)

    Briney, Bryan S; Willis, Jordan R; Hicar, Mark D; Thomas, James W; Crowe, James E

    2012-09-01

    Antibody heavy-chain recombination that results in the incorporation of multiple diversity (D) genes, although uncommon, contributes substantially to the diversity of the human antibody repertoire. Such recombination allows the generation of heavy chain complementarity determining region 3 (HCDR3) regions of extreme length and enables junctional regions that, because of the nucleotide bias of N-addition regions, are difficult to produce through normal V(D)J recombination. Although this non-classical recombination process has been observed infrequently, comprehensive analysis of the frequency and genetic characteristics of such events in the human peripheral blood antibody repertoire has not been possible because of the rarity of such recombinants and the limitations of traditional sequencing technologies. Here, through the use of high-throughput sequencing of the normal human peripheral blood antibody repertoire, we analysed the frequency and genetic characteristics of V(DD)J recombinants. We found that these recombinations were present in approximately 1 in 800 circulating B cells, and that the frequency was severely reduced in memory cell subsets. We also found that V(DD)J recombination can occur across the spectrum of diversity genes, indicating that virtually all recombination signal sequences that flank diversity genes are amenable to V(DD)J recombination. Finally, we observed a repertoire bias in the diversity gene repertoire at the upstream (5') position, and discovered that this bias was primarily attributable to the order of diversity genes in the genomic locus. © 2012 The Authors. Immunology © 2012 Blackwell Publishing Ltd.

  7. The Lepidoptera Odorant Binding Protein gene family: Gene gain and loss within the GOBP/PBP complex of moths and butterflies.

    Science.gov (United States)

    Vogt, Richard G; Große-Wilde, Ewald; Zhou, Jing-Jiang

    2015-07-01

    Butterflies and moths differ significantly in their daily activities: butterflies are diurnal while moths are largely nocturnal or crepuscular. This life history difference is presumably reflected in their sensory biology, and especially the balance between the use of chemical versus visual signals. Odorant Binding Proteins (OBP) are a class of insect proteins, at least some of which are thought to orchestrate the transfer of odor molecules within an olfactory sensillum (olfactory organ), between the air and odor receptor proteins (ORs) on the olfactory neurons. A Lepidoptera specific subclass of OBPs are the GOBPs and PBPs; these were the first OBPs studied and have well documented associations with olfactory sensilla. We have used the available genomes of two moths, Manduca sexta and Bombyx mori, and two butterflies, Danaus plexippus and Heliconius melpomene, to characterize the GOBP/PBP genes, attempting to identify gene orthologs and document specific gene gain and loss. First, we identified the full repertoire of OBPs in the M. sexta genome, and compared these with the full repertoire of OBPs from the other three lepidopteran genomes, the OBPs of Drosophila melanogaster and select OBPs from other Lepidoptera. We also evaluated the tissue specific expression of the M. sexta OBPs using an available RNAseq databases. In the four lepidopteran species, GOBP2 and all PBPs reside in single gene clusters; in two species GOBP1 is documented to be nearby, about 100 kb from the cluster; all GOBP/PBP genes share a common gene structure indicating a common origin. As such, the GOBP/PBP genes form a gene complex. Our findings suggest that (1) the lepidopteran GOBP/PBP complex is a monophyletic lineage with origins deep within Lepidoptera phylogeny, (2) within this lineage PBP gene evolution is much more dynamic than GOBP gene evolution, and (3) butterflies may have lost a PBP gene that plays an important role in moth pheromone detection, correlating with a shift from

  8. Study of Sylvilagus rabbit TRIM5α species-specific domain: how ancient endoviruses could have shaped the antiviral repertoire in Lagomorpha

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    Areal Helena

    2011-10-01

    Full Text Available Abstract Background Since the first report of the antiretroviral restriction factor TRIM5α in primates, several orthologs in other mammals have been described. Recent studies suggest that leporid retroviruses like RELIK, the first reported endogenous lentivirus ever, may have imposed positive selection in TRIM5α orthologs of the European rabbit and European brown hare. Considering that RELIK must already have been present in a common ancestor of the leporid genera Lepus, Sylvilagus and Oryctolagus, we extended the study of evolutionary patterns of TRIM5α to other members of the Leporidae family, particularly to the genus Sylvilagus. Therefore, we obtained the TRIM5α nucleotide sequences of additional subspecies and species of the three leporid genera. We also compared lagomorph TRIM5α deduced protein sequences and established TRIM5α gene and TRIM5α protein phylogenies. Results The deduced protein sequence of Iberian hare TRIM5α was 89% identical to European rabbit TRIM5α, although high divergence was observed at the PRYSPRY v1 region between rabbit and the identified alleles from this hare species (allele 1: 50% divergence; allele 2: 53% divergence. A high identity was expected between the Sylvilagus and Oryctolagus TRIM5α proteins and, in fact, the Sylvilagus TRIM5α was 91% identical to the Oryctolagus protein. Nevertheless, the PRYSPRY v1 region was only 50% similar between these genera. Selection analysis of Lagomorpha TRIM5α proteins identified 25 positively-selected codons, 11 of which are located in the PRYSPRY v1 region, responsible for species specific differences in viral capsid recognition. Conclusions By extending Lagomorpha TRIM5α studies to an additional genus known to bear RELIK, we verified that the divergent species-specific pattern observed between the Oryctolagus and Lepus PRYSPRY-domains is also present in Sylvilagus TRIM5α. This work is one of the first known studies that compare the evolution of the

  9. Revisiting the missing protein-coding gene catalog of the domestic dog

    Directory of Open Access Journals (Sweden)

    Galibert Francis

    2009-02-01

    Full Text Available Abstract Background Among mammals for which there is a high sequence coverage, the whole genome assembly of the dog is unique in that it predicts a low number of protein-coding genes, ~19,000, compared to the over 20,000 reported for other mammalian species. Of particular interest are the more than 400 of genes annotated in primates and rodent genomes, but missing in dog. Results Using over 14,000 orthologous genes between human, chimpanzee, mouse rat and dog, we built multiple pairwise synteny maps to infer short orthologous intervals that were targeted for characterizing the canine missing genes. Based on gene prediction and a functionality test using the ratio of replacement to silent nucleotide substitution rates (dN/dS, we provide compelling structural and functional evidence for the identification of 232 new protein-coding genes in the canine genome and 69 gene losses, characterized as undetected gene or pseudogenes. Gene loss phyletic pattern analysis using ten species from chicken to human allowed us to characterize 28 canine-specific gene losses that have functional orthologs continuously from chicken or marsupials through human, and 10 genes that arose specifically in the evolutionary lineage leading to rodent and primates. Conclusion This study demonstrates the central role of comparative genomics for refining gene catalogs and exploring the evolutionary history of gene repertoires, particularly as applied for the characterization of species-specific gene gains and losses.

  10. Antibodies: From novel repertoires to defining and refining the structure of biologically important targets.

    Science.gov (United States)

    Conroy, Paul J; Law, Ruby H P; Caradoc-Davies, Tom T; Whisstock, James C

    2017-03-01

    Antibodies represent a highly successful class of molecules that bind a wide-range of targets in therapeutic-, diagnostic- and research-based applications. The antibody repertoire is composed of the building blocks required to develop an effective adaptive immune response against foreign insults. A number of species have developed novel genetic and structural mechanisms from which they derive these antibody repertoires, however, traditionally antibodies are isolated from human, and rodent sources. Due to their high-value therapeutic, diagnostic, biotechnological and research applications, much innovation has resulted in techniques and approaches to isolate novel antibodies. These approaches are bolstered by advances in our understanding of species immune repertoires, next generation sequencing capacity, combinatorial antibody discovery and high-throughput screening. Structural determination of antibodies and antibody-antigen complexes has proven to be pivotal to our current understanding of the immune repertoire for a range of species leading to advances in man-made libraries and fine tuning approaches to develop antibodies from immune-repertoires. Furthermore, the isolation of antibodies directed against antigens of importance in health, disease and developmental processes, has yielded a plethora of structural and functional insights. This review highlights the significant contribution of antibody-based crystallography to our understanding of adaptive immunity and its application to providing critical information on a range of human-health related indications. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Identification of antigen-specific human monoclonal antibodies using high-throughput sequencing of the antibody repertoire.

    Science.gov (United States)

    Liu, Ju; Li, Ruihua; Liu, Kun; Li, Liangliang; Zai, Xiaodong; Chi, Xiangyang; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-04-22

    High-throughput sequencing of the antibody repertoire provides a large number of antibody variable region sequences that can be used to generate human monoclonal antibodies. However, current screening methods for identifying antigen-specific antibodies are inefficient. In the present study, we developed an antibody clone screening strategy based on clone dynamics and relative frequency, and used it to identify antigen-specific human monoclonal antibodies. Enzyme-linked immunosorbent assay showed that at least 52% of putative positive immunoglobulin heavy chains composed antigen-specific antibodies. Combining information on dynamics and relative frequency improved identification of positive clones and elimination of negative clones. and increase the credibility of putative positive clones. Therefore the screening strategy could simplify the subsequent experimental screening and may facilitate the generation of antigen-specific antibodies. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Flexible cultural repertoires

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz; Zimmermann, Francisca

    2017-01-01

    Despite extensive studies of street culture and the risks of offending and victimization in urban marginalized areas, little is known about the role of cultural repertoires for variation in victimization risks among young men not involved in crime. Based on two ethnographic studies, conducted...... independently of the authors in neighbouring township areas of Cape Town, we offer insights into patterns of victimization among young men not involved in crime who live and attend school in the townships. Young men WHO perform decent cultural repertoires are highly exposed to victimization due to their moral...... rejection of crime-involved youth. Young men who perform flexible cultural repertoires, by incorporating and shifting between gang and decent repertoires, experience low victimization due to their adaptation to crime-involved youth. Findings emphasize the importance of detailed investigations of the way...

  13. Endometrial natural killer (NK) cells reveal a tissue-specific receptor repertoire.

    Science.gov (United States)

    Feyaerts, D; Kuret, T; van Cranenbroek, B; van der Zeeuw-Hingrez, S; van der Heijden, O W H; van der Meer, A; Joosten, I; van der Molen, R G

    2018-02-13

    Is the natural killer (NK) cell receptor repertoire of endometrial NK (eNK) cells tissue-specific? The NK cell receptor (NKR) expression profile in pre-pregnancy endometrium appears to have a unique tissue-specific phenotype, different from that found in NK cells in peripheral blood, suggesting that these cells are finely tuned towards the reception of an allogeneic fetus. NK cells are important for successful pregnancy. After implantation, NK cells encounter extravillous trophoblast cells and regulate trophoblast invasion. NK cell activity is amongst others regulated by C-type lectin heterodimer (CD94/NKG2) and killer cell immunoglobulin-like (KIR) receptors. KIR expression on decidual NK cells is affected by the presence of maternal HLA-C and biased towards KIR2D expression. However, little is known about NKR expression on eNK cells prior to pregnancy. In this study, matched peripheral and menstrual blood (a source of endometrial cells) was obtained from 25 healthy females with regular menstrual cycles. Menstrual blood was collected during the first 36 h of menstruation using a menstrual cup, a non-invasive technique to obtain endometrial cells. KIR and NKG2 receptor expression on eNK cells was characterized by 10-color flow cytometry, and compared to matched pbNK cells of the same female. KIR and HLA-C genotypes were determined by PCR-SSOP techniques. Anti-CMV IgG antibodies in plasma were measured by chemiluminescence immunoassay. KIR expression patterns of eNK cells collected from the same female do not differ over consecutive menstrual cycles. The percentage of NK cells expressing KIR2DL2/L3/S2, KIR2DL3, KIR2DL1, LILRB1 and/or NKG2A was significantly higher in eNK cells compared to pbNK cells, while no significant difference was observed for NKG2C, KIR2DL1/S1, and KIR3DL1. The NKR repertoire of eNK cells was clearly different from pbNK cells, with eNK cells co-expressing more than three NKR simultaneously. In addition, outlier analysis revealed 8 and 15 NKR

  14. Molecular identification of Nocardia species using the sodA gene

    Directory of Open Access Journals (Sweden)

    K. Sánchez-Herrera

    2017-09-01

    Full Text Available Currently for bacterial identification and classification the rrs gene encoding 16S rRNA is used as a reference method for the analysis of strains of the genus Nocardia. However, it does not have enough polymorphism to differentiate them at the species level. This fact makes it necessary to search for molecular targets that can provide better identification. The sodA gene (encoding the enzyme superoxide dismutase has had good results in identifying species of other Actinomycetes. In this study the sodA gene is proposed for the identification and differentiation at the species level of the genus Nocardia. We used 41 type species of various collections; a 386 bp fragment of the sodA gene was amplified and sequenced, and a phylogenetic analysis was performed comparing the genes rrs (1171 bp, hsp65 (401 bp, secA1 (494 bp, gyrB (1195 bp and rpoB (401 bp. The sequences were aligned using the Clustal X program. Evolutionary trees according to the neighbour-joining method were created with the programs Phylo_win and MEGA 6. The specific variability of the sodA genus of the genus Nocardia was analysed. A high phylogenetic resolution, significant genetic variability, and specificity and reliability were observed for the differentiation of the isolates at the species level. The polymorphism observed in the sodA gene sequence contains variable regions that allow the discrimination of closely related Nocardia species. The clear specificity, despite its small size, proves to be of great advantage for use in taxonomic studies and clinical diagnosis of the genus Nocardia.

  15. Local Chromatin Features Including PU.1 and IKAROS Binding and H3K4 Methylation Shape the Repertoire of Immunoglobulin Kappa Genes Chosen for V(DJ Recombination

    Directory of Open Access Journals (Sweden)

    Louise S. Matheson

    2017-11-01

    Full Text Available V(DJ recombination is essential for the generation of diverse antigen receptor (AgR repertoires. In B cells, immunoglobulin kappa (Igκ light chain recombination follows immunoglobulin heavy chain (Igh recombination. We recently developed the DNA-based VDJ-seq assay for the unbiased quantitation of Igh VH and DH repertoires. Integration of VDJ-seq data with genome-wide datasets revealed that two chromatin states at the recombination signal sequence (RSS of VH genes are highly predictive of recombination in mouse pro-B cells. It is unknown whether local chromatin states contribute to Vκ gene choice during Igκ recombination. Here we adapt VDJ-seq to profile the Igκ VκJκ repertoire and present a comprehensive readout in mouse pre-B cells, revealing highly variable Vκ gene usage. Integration with genome-wide datasets for histone modifications, DNase hypersensitivity, transcription factor binding and germline transcription identified PU.1 binding at the RSS, which was unimportant for Igh, as highly predictive of whether a Vκ gene will recombine or not, suggesting that it plays a binary, all-or-nothing role, priming genes for recombination. Thereafter, the frequency with which these genes recombine was shaped both by the presence and level of enrichment of several other chromatin features, including H3K4 methylation and IKAROS binding. Moreover, in contrast to the Igh locus, the chromatin landscape of the promoter, as well as of the RSS, contributes to Vκ gene recombination. Thus, multiple facets of local chromatin features explain much of the variation in Vκ gene usage. Together, these findings reveal shared and divergent roles for epigenetic features and transcription factors in AgR V(DJ recombination and provide avenues for further investigation of chromatin signatures that may underpin V(DJ-mediated chromosomal translocations.

  16. Characterization and gene expression analysis of the cir multi-gene family of plasmodium chabaudi chabaudi (AS)

    KAUST Repository

    Lawton, Jennifer

    2012-03-29

    Background: The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due to antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism, allowing evasion of host immune responses. In order to fully understand the role(s) of CIR proteins during P. chabaudi infection, a detailed characterization of the cir gene family was required.Results: The cir repertoire was annotated and a detailed bioinformatic characterization of the encoded CIR proteins was performed. Two major sub-families were identified, which have been named A and B. Members of each sub-family displayed different amino acid motifs, and were thus predicted to have undergone functional divergence. In addition, the expression of the entire cir repertoire was analyzed via RNA sequencing and microarray. Up to 40% of the cir gene repertoire was expressed in the parasite population during infection, and dominant cir transcripts could be identified. In addition, some differences were observed in the pattern of expression between the cir subgroups at the peak of P. chabaudi infection. Finally, specific cir genes were expressed at different time points during asexual blood stages.Conclusions: In conclusion, the large number of cir genes and their expression throughout the intraerythrocytic cycle of development indicates that CIR proteins are likely to be important for parasite survival. In particular, the detection of dominant cir transcripts at the peak of P. chabaudi infection supports the idea that CIR proteins are expressed, and could perform important functions in the biology of this parasite. Further application of the methodologies described here may allow the elucidation of CIR sub-family A and B protein

  17. Characterization and gene expression analysis of the cir multi-gene family of plasmodium chabaudi chabaudi (AS

    Directory of Open Access Journals (Sweden)

    Lawton Jennifer

    2012-03-01

    Full Text Available Abstract Background The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due to antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism, allowing evasion of host immune responses. In order to fully understand the role(s of CIR proteins during P. chabaudi infection, a detailed characterization of the cir gene family was required. Results The cir repertoire was annotated and a detailed bioinformatic characterization of the encoded CIR proteins was performed. Two major sub-families were identified, which have been named A and B. Members of each sub-family displayed different amino acid motifs, and were thus predicted to have undergone functional divergence. In addition, the expression of the entire cir repertoire was analyzed via RNA sequencing and microarray. Up to 40% of the cir gene repertoire was expressed in the parasite population during infection, and dominant cir transcripts could be identified. In addition, some differences were observed in the pattern of expression between the cir subgroups at the peak of P. chabaudi infection. Finally, specific cir genes were expressed at different time points during asexual blood stages. Conclusions In conclusion, the large number of cir genes and their expression throughout the intraerythrocytic cycle of development indicates that CIR proteins are likely to be important for parasite survival. In particular, the detection of dominant cir transcripts at the peak of P. chabaudi infection supports the idea that CIR proteins are expressed, and could perform important functions in the biology of this parasite. Further application of the methodologies described here may allow the elucidation of CIR sub

  18. Characterization and gene expression analysis of the cir multi-gene family of plasmodium chabaudi chabaudi (AS)

    KAUST Repository

    Lawton, Jennifer; Brugat, Thibaut; Yan, Yam Xue; Reid, Adam James; Bö hme, Ulrike; Otto, Thomas Dan; Pain, Arnab; Jackson, Andrew; Berriman, Matthew; Cunningham, Deirdre; Preiser, Peter; Langhorne, Jean

    2012-01-01

    Background: The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due to antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism, allowing evasion of host immune responses. In order to fully understand the role(s) of CIR proteins during P. chabaudi infection, a detailed characterization of the cir gene family was required.Results: The cir repertoire was annotated and a detailed bioinformatic characterization of the encoded CIR proteins was performed. Two major sub-families were identified, which have been named A and B. Members of each sub-family displayed different amino acid motifs, and were thus predicted to have undergone functional divergence. In addition, the expression of the entire cir repertoire was analyzed via RNA sequencing and microarray. Up to 40% of the cir gene repertoire was expressed in the parasite population during infection, and dominant cir transcripts could be identified. In addition, some differences were observed in the pattern of expression between the cir subgroups at the peak of P. chabaudi infection. Finally, specific cir genes were expressed at different time points during asexual blood stages.Conclusions: In conclusion, the large number of cir genes and their expression throughout the intraerythrocytic cycle of development indicates that CIR proteins are likely to be important for parasite survival. In particular, the detection of dominant cir transcripts at the peak of P. chabaudi infection supports the idea that CIR proteins are expressed, and could perform important functions in the biology of this parasite. Further application of the methodologies described here may allow the elucidation of CIR sub-family A and B protein

  19. PanCoreGen - Profiling, detecting, annotating protein-coding genes in microbial genomes.

    Science.gov (United States)

    Paul, Sandip; Bhardwaj, Archana; Bag, Sumit K; Sokurenko, Evgeni V; Chattopadhyay, Sujay

    2015-12-01

    A large amount of genomic data, especially from multiple isolates of a single species, has opened new vistas for microbial genomics analysis. Analyzing the pan-genome (i.e. the sum of genetic repertoire) of microbial species is crucial in understanding the dynamics of molecular evolution, where virulence evolution is of major interest. Here we present PanCoreGen - a standalone application for pan- and core-genomic profiling of microbial protein-coding genes. PanCoreGen overcomes key limitations of the existing pan-genomic analysis tools, and develops an integrated annotation-structure for a species-specific pan-genomic profile. It provides important new features for annotating draft genomes/contigs and detecting unidentified genes in annotated genomes. It also generates user-defined group-specific datasets within the pan-genome. Interestingly, analyzing an example-set of Salmonella genomes, we detect potential footprints of adaptive convergence of horizontally transferred genes in two human-restricted pathogenic serovars - Typhi and Paratyphi A. Overall, PanCoreGen represents a state-of-the-art tool for microbial phylogenomics and pathogenomics study. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. The past, present and future of immune repertoire biology – the rise of next-generation repertoire analysis

    Directory of Open Access Journals (Sweden)

    Adrien eSix

    2013-11-01

    Full Text Available T and B cell repertoires are collections of lymphocytes, each characterised by its antigen-specific receptor. We review here classical technologies and analysis strategies developed to assess Immunoglobulin (IG and T cell receptor (TR repertoire diversity, and describe recent advances in the field. First, we describe the broad range of available methodological tools developed in the past decades, each of which answering different questions and showing complementarity for progressive identification of the level of repertoire alterations: global overview of the diversity by flow cytometry, IG repertoire descriptions at the protein level for the identification of IG reactivities, IG/TR CDR3 spectratyping strategies, and related molecular quantification or dynamics of T/B cell differentiation. Additionally, we introduce the recent technological advances in molecular biology tools allowing deeper analysis of IG/TR diversity by next-generation sequencing (NGS, offering systematic and comprehensive sequencing of IG/TR transcripts in a short amount of time. NGS provides several angles of analysis such as clonotype frequency, CDR3 diversity, CDR3 sequence analysis, V allele identification with a quantitative dimension, therefore requiring high-throughput analysis tools development. In this line, we discuss the recent efforts made for nomenclature standardisation and ontology development. We then present the variety of available statistical analysis and modelling approaches developed with regards to the various levels of diversity analysis, and reveal the increasing sophistication of modelling approaches. To conclude, we provide some examples of recent mathematical modelling strategies and perspectives that illustrate the active rise of a next-generation of repertoire analysis.

  1. Local Chromatin Features Including PU.1 and IKAROS Binding and H3K4 Methylation Shape the Repertoire of Immunoglobulin Kappa Genes Chosen for V(D)J Recombination

    OpenAIRE

    Louise S. Matheson; Daniel J. Bolland; Peter Chovanec; Felix Krueger; Simon Andrews; Hashem Koohy; Anne E. Corcoran

    2017-01-01

    V(D)J recombination is essential for the generation of diverse antigen receptor (AgR) repertoires. In B cells, immunoglobulin kappa (Igκ) light chain recombination follows immunoglobulin heavy chain (Igh) recombination. We recently developed the DNA-based VDJ-seq assay for the unbiased quantitation of Igh VH and DH repertoires. Integration of VDJ-seq data with genome-wide datasets revealed that two chromatin states at the recombination signal sequence (RSS) of VH genes are highly predictive o...

  2. Strategies for B-cell receptor repertoire analysis in Primary Immunodeficiencies:From severe combined immunodeficiency to common variable immunodeficiency

    Directory of Open Access Journals (Sweden)

    Hanna eIJspeert

    2015-04-01

    Full Text Available The antigen receptor repertoires of B and T cells form the basis of the adaptive immune response. The repertoires should be sufficiently diverse to recognize all possible pathogens. However, careful selection is needed to prevent responses to self or harmless antigens. Limited antigen receptor repertoire diversity leads to immunodeficiency, whereas unselected or misdirected repertoires can result in autoimmunity. The antigen receptor repertoire harbors information about abnormalities in many immunological disorders. Recent developments in next generation sequencing allow the analysis of the antigen receptor repertoire in much greater detail than ever before. Analyzing the antigen receptor repertoire in patients with mutations in genes responsible for the generation of the antigen receptor repertoire will give new insights into repertoire formation and selection. In this perspective we describe strategies and considerations for analysis of the naive and antigen selected B-cell repertoires in primary immunodeficiency (PID patients with a focus on severe combined immunodeficiency (SCID and common variable immunodeficiency (CVID.

  3. An Annotated Guide and Interactive Database for Solo Horn Repertoire

    Science.gov (United States)

    Schouten, Sarah

    2012-01-01

    Given the horn's lengthy history, it is not surprising that many scholars have examined the evolution of the instrument from the natural horn to the modern horn and its expansive repertoire. Numerous dissertations, theses, and treatises illuminate specific elements of the horn's solo repertoire; however, no scholar has produced a…

  4. Local Chromatin Features Including PU.1 and IKAROS Binding and H3K4 Methylation Shape the Repertoire of Immunoglobulin Kappa Genes Chosen for V(D)J Recombination.

    Science.gov (United States)

    Matheson, Louise S; Bolland, Daniel J; Chovanec, Peter; Krueger, Felix; Andrews, Simon; Koohy, Hashem; Corcoran, Anne E

    2017-01-01

    V(D)J recombination is essential for the generation of diverse antigen receptor (AgR) repertoires. In B cells, immunoglobulin kappa ( Igκ ) light chain recombination follows immunoglobulin heavy chain ( Igh ) recombination. We recently developed the DNA-based VDJ-seq assay for the unbiased quantitation of Igh VH and DH repertoires. Integration of VDJ-seq data with genome-wide datasets revealed that two chromatin states at the recombination signal sequence (RSS) of VH genes are highly predictive of recombination in mouse pro-B cells. It is unknown whether local chromatin states contribute to Vκ gene choice during Igκ recombination. Here we adapt VDJ-seq to profile the Igκ VκJκ repertoire and present a comprehensive readout in mouse pre-B cells, revealing highly variable Vκ gene usage. Integration with genome-wide datasets for histone modifications, DNase hypersensitivity, transcription factor binding and germline transcription identified PU.1 binding at the RSS, which was unimportant for Igh , as highly predictive of whether a Vκ gene will recombine or not, suggesting that it plays a binary, all-or-nothing role, priming genes for recombination. Thereafter, the frequency with which these genes recombine was shaped both by the presence and level of enrichment of several other chromatin features, including H3K4 methylation and IKAROS binding. Moreover, in contrast to the Igh locus, the chromatin landscape of the promoter, as well as of the RSS, contributes to Vκ gene recombination. Thus, multiple facets of local chromatin features explain much of the variation in Vκ gene usage. Together, these findings reveal shared and divergent roles for epigenetic features and transcription factors in AgR V(D)J recombination and provide avenues for further investigation of chromatin signatures that may underpin V(D)J-mediated chromosomal translocations.

  5. Defensive repertoire of Drosophila larvae in response to toxic fungi.

    Science.gov (United States)

    Trienens, Monika; Kraaijeveld, Ken; Wertheim, Bregje

    2017-10-01

    Chemical warfare including insecticidal secondary metabolites is a well-known strategy for environmental microbes to monopolize a food source. Insects in turn have evolved behavioural and physiological defences to eradicate or neutralize the harmful microorganisms. We studied the defensive repertoire of insects in this interference competition by combining behavioural and developmental assays with whole-transcriptome time-series analysis. Confrontation with the toxic filamentous fungus Aspergillus nidulans severely reduced the survival of Drosophila melanogaster larvae. Nonetheless, the larvae did not behaviourally avoid the fungus, but aggregated at it. Confrontation with fungi strongly affected larval gene expression, including many genes involved in detoxification (e.g., CYP, GST and UGT genes) and the formation of the insect cuticle (e.g., Tweedle genes). The most strongly upregulated genes were several members of the insect-specific gene family Osiris, and CHK-kinase-like domains were over-represented. Immune responses were not activated, reflecting the competitive rather than pathogenic nature of the antagonistic interaction. While internal microbes are widely acknowledged as important, our study emphasizes the underappreciated role of environmental microbes as fierce competitors. © 2017 John Wiley & Sons Ltd.

  6. PanCoreGen – profiling, detecting, annotating protein-coding genes in microbial genomes

    Science.gov (United States)

    Bhardwaj, Archana; Bag, Sumit K; Sokurenko, Evgeni V.

    2015-01-01

    A large amount of genomic data, especially from multiple isolates of a single species, has opened new vistas for microbial genomics analysis. Analyzing pan-genome (i.e. the sum of genetic repertoire) of microbial species is crucial in understanding the dynamics of molecular evolution, where virulence evolution is of major interest. Here we present PanCoreGen – a standalone application for pan- and core-genomic profiling of microbial protein-coding genes. PanCoreGen overcomes key limitations of the existing pan-genomic analysis tools, and develops an integrated annotation-structure for species-specific pan-genomic profile. It provides important new features for annotating draft genomes/contigs and detecting unidentified genes in annotated genomes. It also generates user-defined group-specific datasets within the pan-genome. Interestingly, analyzing an example-set of Salmonella genomes, we detect potential footprints of adaptive convergence of horizontally transferred genes in two human-restricted pathogenic serovars – Typhi and Paratyphi A. Overall, PanCoreGen represents a state-of-the-art tool for microbial phylogenomics and pathogenomics study. PMID:26456591

  7. The chromosomal organization of horizontal gene transfer in bacteria.

    Science.gov (United States)

    Oliveira, Pedro H; Touchon, Marie; Cury, Jean; Rocha, Eduardo P C

    2017-10-10

    Bacterial adaptation is accelerated by the acquisition of novel traits through horizontal gene transfer, but the integration of these genes affects genome organization. We found that transferred genes are concentrated in only ~1% of the chromosomal regions (hotspots) in 80 bacterial species. This concentration increases with genome size and with the rate of transfer. Hotspots diversify by rapid gene turnover; their chromosomal distribution depends on local contexts (neighboring core genes), and content in mobile genetic elements. Hotspots concentrate most changes in gene repertoires, reduce the trade-off between genome diversification and organization, and should be treasure troves of strain-specific adaptive genes. Most mobile genetic elements and antibiotic resistance genes are in hotspots, but many hotspots lack recognizable mobile genetic elements and exhibit frequent homologous recombination at flanking core genes. Overrepresentation of hotspots with fewer mobile genetic elements in naturally transformable bacteria suggests that homologous recombination and horizontal gene transfer are tightly linked in genome evolution.Horizontal gene transfer (HGT) is an important mechanism for genome evolution and adaptation in bacteria. Here, Oliveira and colleagues find HGT hotspots comprising  ~ 1% of the chromosomal regions in 80 bacterial species.

  8. Diversity and repertoire of IgW and IgM VH families in the newborn nurse shark.

    Science.gov (United States)

    Rumfelt, Lynn L; Lohr, Rebecca L; Dooley, Helen; Flajnik, Martin F

    2004-05-06

    Adult cartilaginous fish express three immunoglobulin (Ig) isotypes, IgM, IgNAR and IgW. Newborn nurse sharks, Ginglymostoma cirratum, produce 19S (multimeric) IgM and monomeric/dimeric IgM1gj, a germline-joined, IgM-related VH, and very low amounts of 7S (monomeric) IgM and IgNAR proteins. Newborn IgNAR VH mRNAs are diverse in the complementarity-determining region 3 (CDR3) with non-templated nucleotide (N-region) addition, which suggests that, unlike in many other vertebrates, terminal deoxynucleotidyl transferase (TdT) expressed at birth is functional. IgW is present in the lungfish, a bony fish sharing a common ancestor with sharks 460 million years ago, implying that the IgW VH family is as old as the IgM VH family. This nurse shark study examined the IgM and IgW VH repertoire from birth through adult life, and analyzed the phylogenetic relationships of these gene families. IgM and IgW VH cDNA clones isolated from newborn nurse shark primary and secondary lymphoid tissues had highly diverse and unique CDR3 with N-region addition and VDJ gene rearrangement, implicating functional TdT and RAG gene activity. Despite the clear presence of N-region additions, newborn CDR3 were significantly shorter than those of adults. The IgM clones are all included in a conventional VH family that can be classified into five discrete groups, none of which is orthologous to IgM VH genes in other elasmobranchs. In addition, a novel divergent VH family was orthologous to a published monotypic VH horn shark family. IgW VH genes have diverged sufficiently to form three families. IgM and IgW VH serine codons using the potential somatic hypermutation hotspot sequence occur mainly in VH framework 1 (FR1) and CDR1. Phylogenetic analysis of cartilaginous fish and lungfish IgM and IgW demonstrated they form two major ancient gene groups; furthermore, these VH genes generally diversify (duplicate and diverge) within a species. As in ratfish, sandbar and horn sharks, most nurse shark IgM VH

  9. Characteristics of the Lotus japonicus gene repertoire deduced from large-scale expressed sequence tag (EST) analysis.

    Science.gov (United States)

    Asamizu, Erika; Nakamura, Yasukazu; Sato, Shusei; Tabata, Satoshi

    2004-02-01

    To perform a comprehensive analysis of genes expressed in a model legume, Lotus japonicus, a total of 74472 3'-end expressed sequence tags (EST) were generated from cDNA libraries produced from six different organs. Clustering of sequences was performed with an identity criterion of 95% for 50 bases, and a total of 20457 non-redundant sequences, 8503 contigs and 11954 singletons were generated. EST sequence coverage was analyzed by using the annotated L. japonicus genomic sequence and 1093 of the 1889 predicted protein-encoding genes (57.9%) were hit by the EST sequence(s). Gene content was compared to several plant species. Among the 8503 contigs, 471 were identified as sequences conserved only in leguminous species and these included several disease resistance-related genes. This suggested that in legumes, these genes may have evolved specifically to resist pathogen attack. The rate of gene sequence divergence was assessed by comparing similarity level and functional category based on the Gene Ontology (GO) annotation of Arabidopsis genes. This revealed that genes encoding ribosomal proteins, as well as those related to translation, photosynthesis, and cellular structure were more abundantly represented in the highly conserved class, and that genes encoding transcription factors and receptor protein kinases were abundantly represented in the less conserved class. To make the sequence information and the cDNA clones available to the research community, a Web database with useful services was created at http://www.kazusa.or.jp/en/plant/lotus/EST/.

  10. Contribution of V(H replacement products in mouse antibody repertoire.

    Directory of Open Access Journals (Sweden)

    Lin Huang

    Full Text Available VH replacement occurs through RAG-mediated recombination between the cryptic recombination signal sequence (cRSS near the 3' end of a rearranged VH gene and the 23-bp RSS from an upstream unrearranged VH gene. Due to the location of the cRSS, VH replacement leaves a short stretch of nucleotides from the previously rearranged VH gene at the newly formed V-D junction, which can be used as a marker to identify VH replacement products. To determine the contribution of VH replacement products to mouse antibody repertoire, we developed a Java-based VH Replacement Footprint Analyzer (VHRFA program and analyzed 17,179 mouse IgH gene sequences from the NCBI database to identify VH replacement products. The overall frequency of VH replacement products in these IgH genes is 5.29% based on the identification of pentameric VH replacement footprints at their V-D junctions. The identified VH replacement products are distributed similarly in IgH genes using most families of VH genes, although different families of VH genes are used differentially. The frequencies of VH replacement products are significantly elevated in IgH genes derived from several strains of autoimmune prone mice and in IgH genes encoding autoantibodies. Moreover, the identified VH replacement footprints in IgH genes from autoimmune prone mice or IgH genes encoding autoantibodies preferentially encode positively charged amino acids. These results revealed a significant contribution of VH replacement products to the diversification of antibody repertoire and potentially, to the generation of autoantibodies in mice.

  11. Description of electrophoretic loci and tissue specific gene ...

    African Journals Online (AJOL)

    Protein electrophoresis was used to study the distributions and tissue specificity of gene expression of enzymes encoded by 42 loci in Rhinolophus clivosus and R. landeri, the genetically most divergent of the ten species of southern African horseshoe bats. No differences in gene expression were found between R.

  12. Species-Specific Mechanisms of Neuron Subtype Specification Reveal Evolutionary Plasticity of Amniote Brain Development

    Directory of Open Access Journals (Sweden)

    Tadashi Nomura

    2018-03-01

    Full Text Available Summary: Highly ordered brain architectures in vertebrates consist of multiple neuron subtypes with specific neuronal connections. However, the origin of and evolutionary changes in neuron specification mechanisms remain unclear. Here, we report that regulatory mechanisms of neuron subtype specification are divergent in developing amniote brains. In the mammalian neocortex, the transcription factors (TFs Ctip2 and Satb2 are differentially expressed in layer-specific neurons. In contrast, these TFs are co-localized in reptilian and avian dorsal pallial neurons. Multi-potential progenitors that produce distinct neuronal subtypes commonly exist in the reptilian and avian dorsal pallium, whereas a cis-regulatory element of avian Ctip2 exhibits attenuated transcription suppressive activity. Furthermore, the neuronal subtypes distinguished by these TFs are not tightly associated with conserved neuronal connections among amniotes. Our findings reveal the evolutionary plasticity of regulatory gene functions that contribute to species differences in neuronal heterogeneity and connectivity in developing amniote brains. : Neuronal heterogeneity is essential for assembling intricate neuronal circuits. Nomura et al. find that species-specific transcriptional mechanisms underlie diversities of excitatory neuron subtypes in mammalian and non-mammalian brains. Species differences in neuronal subtypes and connections suggest functional plasticity of regulatory genes for neuronal specification during amniote brain evolution. Keywords: Ctip2, Satb2, multi-potential progenitors, transcriptional regulation, neuronal connectivity

  13. Species-specific evolution of class I MHC genes in iguanas (order: Squamata; subfamily: Iguaninae).

    Science.gov (United States)

    Glaberman, Scott; Caccone, Adalgisa

    2008-07-01

    Over the last few decades, the major histocompatibility complex (MHC) has emerged as a model for understanding the influence of natural selection on genetic diversity in populations as well as for investigating the genetic basis of host resistance to pathogens. However, many vertebrate taxa remain underrepresented in the field of MHC research, preventing its application to studies of disease, evolution, and conservation genetics in these groups. This is particularly true for squamates, which are by far the most diversified order of non-avian reptiles but have not been the subject of any recent MHC studies. In this paper, we present MHC class I complementary DNA data from three squamate species in the subfamily Iguaninae (iguanas): the Galápagos marine iguana (Amblyrhynchus cristatus), the Galápagos land iguana (Conolophus subcristatus), and the green iguana (Iguana iguana). All sequences obtained are related to the few published class I genes from other squamates. There is evidence for multiple loci in each species, and the conserved alpha-3 domain appears to be evolving in a species-specific manner. Conversely, there is some indication of shared polymorphism between species in the peptide-binding alpha-1 and alpha-2 domains, suggesting that these two regions have different phylogenetic histories. The great similarity between alpha-3 sequences in marine iguanas in particular suggests that concerted evolution is acting to homogenize class I loci within species. However, while less likely, the data are also compatible with a birth and death model of evolution.

  14. Comparative genomic analysis of Drosophila melanogaster and vector mosquito developmental genes.

    Directory of Open Access Journals (Sweden)

    Susanta K Behura

    Full Text Available Genome sequencing projects have presented the opportunity for analysis of developmental genes in three vector mosquito species: Aedes aegypti, Culex quinquefasciatus, and Anopheles gambiae. A comparative genomic analysis of developmental genes in Drosophila melanogaster and these three important vectors of human disease was performed in this investigation. While the study was comprehensive, special emphasis centered on genes that 1 are components of developmental signaling pathways, 2 regulate fundamental developmental processes, 3 are critical for the development of tissues of vector importance, 4 function in developmental processes known to have diverged within insects, and 5 encode microRNAs (miRNAs that regulate developmental transcripts in Drosophila. While most fruit fly developmental genes are conserved in the three vector mosquito species, several genes known to be critical for Drosophila development were not identified in one or more mosquito genomes. In other cases, mosquito lineage-specific gene gains with respect to D. melanogaster were noted. Sequence analyses also revealed that numerous repetitive sequences are a common structural feature of Drosophila and mosquito developmental genes. Finally, analysis of predicted miRNA binding sites in fruit fly and mosquito developmental genes suggests that the repertoire of developmental genes targeted by miRNAs is species-specific. The results of this study provide insight into the evolution of developmental genes and processes in dipterans and other arthropods, serve as a resource for those pursuing analysis of mosquito development, and will promote the design and refinement of functional analysis experiments.

  15. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents.

    Science.gov (United States)

    Haitina, Tatjana; Fredriksson, Robert; Foord, Steven M; Schiöth, Helgi B; Gloriam, David E

    2009-01-15

    The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs) is one of the largest gene families in most mammals and the most exploited in terms of drug discovery. An accurate comparison of the GPCR repertoires in dog and human is valuable for the prediction of functional similarities and differences between the species. We searched the dog genome for non-olfactory GPCRs and obtained 353 full-length GPCR gene sequences, 18 incomplete sequences and 13 pseudogenes. We established relationships between human, dog, rat and mouse GPCRs resolving orthologous pairs and species-specific duplicates. We found that 12 dog GPCR genes are missing in humans while 24 human GPCR genes are not part of the dog GPCR repertoire. There is a higher number of orthologous pairs between dog and human that are conserved as compared with either mouse or rat. In almost all cases the differences observed between the dog and human genomes coincide with other variations in the rodent species. Several GPCR gene expansions characteristic for rodents are not found in dog. The repertoire of dog non-olfactory GPCRs is more similar to the repertoire in humans as compared with the one in rodents. The comparison of the dog, human and rodent repertoires revealed several examples of species-specific gene duplications and deletions. This information is useful in the selection of model organisms for pharmacological experiments.

  16. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents

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    Schiöth Helgi B

    2009-01-01

    Full Text Available Abstract Background The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs is one of the largest gene families in most mammals and the most exploited in terms of drug discovery. An accurate comparison of the GPCR repertoires in dog and human is valuable for the prediction of functional similarities and differences between the species. Results We searched the dog genome for non-olfactory GPCRs and obtained 353 full-length GPCR gene sequences, 18 incomplete sequences and 13 pseudogenes. We established relationships between human, dog, rat and mouse GPCRs resolving orthologous pairs and species-specific duplicates. We found that 12 dog GPCR genes are missing in humans while 24 human GPCR genes are not part of the dog GPCR repertoire. There is a higher number of orthologous pairs between dog and human that are conserved as compared with either mouse or rat. In almost all cases the differences observed between the dog and human genomes coincide with other variations in the rodent species. Several GPCR gene expansions characteristic for rodents are not found in dog. Conclusion The repertoire of dog non-olfactory GPCRs is more similar to the repertoire in humans as compared with the one in rodents. The comparison of the dog, human and rodent repertoires revealed several examples of species-specific gene duplications and deletions. This information is useful in the selection of model organisms for pharmacological experiments.

  17. Comparative gene expression between two yeast species

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    Guan Yuanfang

    2013-01-01

    Full Text Available Abstract Background Comparative genomics brings insight into sequence evolution, but even more may be learned by coupling sequence analyses with experimental tests of gene function and regulation. However, the reliability of such comparisons is often limited by biased sampling of expression conditions and incomplete knowledge of gene functions across species. To address these challenges, we previously systematically generated expression profiles in Saccharomyces bayanus to maximize functional coverage as compared to an existing Saccharomyces cerevisiae data repository. Results In this paper, we take advantage of these two data repositories to compare patterns of ortholog expression in a wide variety of conditions. First, we developed a scalable metric for expression divergence that enabled us to detect a significant correlation between sequence and expression conservation on the global level, which previous smaller-scale expression studies failed to detect. Despite this global conservation trend, between-species gene expression neighborhoods were less well-conserved than within-species comparisons across different environmental perturbations, and approximately 4% of orthologs exhibited a significant change in co-expression partners. Furthermore, our analysis of matched perturbations collected in both species (such as diauxic shift and cell cycle synchrony demonstrated that approximately a quarter of orthologs exhibit condition-specific expression pattern differences. Conclusions Taken together, these analyses provide a global view of gene expression patterns between two species, both in terms of the conditions and timing of a gene's expression as well as co-expression partners. Our results provide testable hypotheses that will direct future experiments to determine how these changes may be specified in the genome.

  18. Gene repertoire evolution of Streptococcus pyogenes inferred from phylogenomic analysis with Streptococcus canis and Streptococcus dysgalactiae.

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    Tristan Lefébure

    Full Text Available Streptococcus pyogenes, is an important human pathogen classified within the pyogenic group of streptococci, exclusively adapted to the human host. Our goal was to employ a comparative evolutionary approach to better understand the genomic events concomitant with S. pyogenes human adaptation. As part of ascertaining these events, we sequenced the genome of one of the potential sister species, the agricultural pathogen S. canis, and combined it in a comparative genomics reconciliation analysis with two other closely related species, Streptococcus dysgalactiae and Streptococcus equi, to determine the genes that were gained and lost during S. pyogenes evolution. Genome wide phylogenetic analyses involving 15 Streptococcus species provided convincing support for a clade of S. equi, S. pyogenes, S. dysgalactiae, and S. canis and suggested that the most likely S. pyogenes sister species was S. dysgalactiae. The reconciliation analysis identified 113 genes that were gained on the lineage leading to S. pyogenes. Almost half (46% of these gained genes were phage associated and 14 showed significant matches to experimentally verified bacteria virulence factors. Subsequent to the origin of S. pyogenes, over half of the phage associated genes were involved in 90 different LGT events, mostly involving different strains of S. pyogenes, but with a high proportion involving the horse specific pathogen S. equi subsp. equi, with the directionality almost exclusively (86% in the S. pyogenes to S. equi direction. Streptococcus agalactiae appears to have played an important role in the evolution of S. pyogenes with a high proportion of LGTs originating from this species. Overall the analysis suggests that S. pyogenes adaptation to the human host was achieved in part by (i the integration of new virulence factors (e.g. speB, and the sal locus and (ii the construction of new regulation networks (e.g. rgg, and to some extent speB.

  19. Next generation sequencing reveals skewing of the T and B cell receptor repertoires in patients with Wiskott Aldrich syndrome

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    Amy E O'Connell

    2014-07-01

    Full Text Available The Wiskott Aldrich syndrome (WAS is due to mutations of the WAS gene encoding for the cytoskeletal WAS protein (WASp, leading to abnormal downstream signaling from the T cell and B cell antigen receptors (TCR, BCR. We hypothesized that the impaired signaling through the TCR and BCR in WAS would subsequently lead to aberrations in the immune repertoire of WAS patients. Using next generation sequencing, the T cell receptor beta (TRB and B cell immunoglobulin heavy chain (IGH repertoires of 8 patients with WAS and 6 controls were sequenced. Clonal expansions were identified within memory CD4+ cells, as well as in total, naïve and memory CD8+ cells from WAS patients. In the B cell compartment, WAS patient IGH repertoires were also clonally expanded and showed skewed usage of IGHV and IGHJ genes, and increased usage of IGHG constant genes, compared with controls. To our knowledge, this is the first study that demonstrates significant abnormalities of the immune repertoire in WAS patients using next generation sequencing.

  20. Difficulties when assessing birdsong learning programmes under field conditions: a re-evaluation of song repertoire flexibility in the great tit.

    Science.gov (United States)

    Rivera-Gutierrez, Hector F; Pinxten, Rianne; Eens, Marcel

    2011-01-17

    There is a remarkable diversity of song-learning strategies in songbirds. Establishing whether a species is closed- or open-ended is important to be able to interpret functional and evolutionary consequences of variation in repertoire size. Most of our knowledge regarding the timing of vocal learning is based on laboratory studies, despite the fact that these may not always replicate the complex ecological and social interactions experienced by birds in the wild. Given that field studies cannot provide the experimental control of laboratory studies, it may not be surprising that species such as the great tit that were initially assumed to be closed-ended learners have later been suggested to be open-ended learners. By using an established colour-ringed population, by following a standardized recording protocol, and by taking into account the species' song ecology (using only recordings obtained during peak of singing at dawn), we replicated two previous studies to assess song repertoire learning and flexibility in adult wild great tits elicited by social interactions. First, we performed a playback experiment to test repertoire plasticity elicited by novel versus own songs. Additionally, in a longitudinal study, we followed 30 males in two consecutive years and analysed whether new neighbours influenced any change in the repertoire. Contrary to the previous studies, song repertoire size and composition were found to be highly repeatable both between years and after confrontation with a novel song. Our results suggest that great tits are closed-ended learners and that their song repertoire probably does not change during adulthood. Methodological differences that may have led to an underestimation of the repertoires or population differences may explain the discrepancy in results with previous studies. We argue that a rigorous and standardized assessment of the repertoire is essential when studying age- or playback-induced changes in repertoire size and composition

  1. Computational Strategies for Dissecting the High-Dimensional Complexity of Adaptive Immune Repertoires

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    Enkelejda Miho

    2018-02-01

    Full Text Available The adaptive immune system recognizes antigens via an immense array of antigen-binding antibodies and T-cell receptors, the immune repertoire. The interrogation of immune repertoires is of high relevance for understanding the adaptive immune response in disease and infection (e.g., autoimmunity, cancer, HIV. Adaptive immune receptor repertoire sequencing (AIRR-seq has driven the quantitative and molecular-level profiling of immune repertoires, thereby revealing the high-dimensional complexity of the immune receptor sequence landscape. Several methods for the computational and statistical analysis of large-scale AIRR-seq data have been developed to resolve immune repertoire complexity and to understand the dynamics of adaptive immunity. Here, we review the current research on (i diversity, (ii clustering and network, (iii phylogenetic, and (iv machine learning methods applied to dissect, quantify, and compare the architecture, evolution, and specificity of immune repertoires. We summarize outstanding questions in computational immunology and propose future directions for systems immunology toward coupling AIRR-seq with the computational discovery of immunotherapeutics, vaccines, and immunodiagnostics.

  2. Diversity and repertoire of IgW and IgM VH families in the newborn nurse shark

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    Dooley Helen

    2004-05-01

    Full Text Available Abstract Background Adult cartilaginous fish express three immunoglobulin (Ig isotypes, IgM, IgNAR and IgW. Newborn nurse sharks, Ginglymostoma cirratum, produce 19S (multimeric IgM and monomeric/dimeric IgM1gj, a germline-joined, IgM-related VH, and very low amounts of 7S (monomeric IgM and IgNAR proteins. Newborn IgNAR VH mRNAs are diverse in the complementarity-determining region 3 (CDR3 with non-templated nucleotide (N-region addition, which suggests that, unlike in many other vertebrates, terminal deoxynucleotidyl transferase (TdT expressed at birth is functional. IgW is present in the lungfish, a bony fish sharing a common ancestor with sharks 460 million years ago, implying that the IgW VH family is as old as the IgM VH family. This nurse shark study examined the IgM and IgW VH repertoire from birth through adult life, and analyzed the phylogenetic relationships of these gene families. Results IgM and IgW VH cDNA clones isolated from newborn nurse shark primary and secondary lymphoid tissues had highly diverse and unique CDR3 with N-region addition and VDJ gene rearrangement, implicating functional TdT and RAG gene activity. Despite the clear presence of N-region additions, newborn CDR3 were significantly shorter than those of adults. The IgM clones are all included in a conventional VH family that can be classified into five discrete groups, none of which is orthologous to IgM VH genes in other elasmobranchs. In addition, a novel divergent VH family was orthologous to a published monotypic VH horn shark family. IgW VH genes have diverged sufficiently to form three families. IgM and IgW VH serine codons using the potential somatic hypermutation hotspot sequence occur mainly in VH framework 1 (FR1 and CDR1. Phylogenetic analysis of cartilaginous fish and lungfish IgM and IgW demonstrated they form two major ancient gene groups; furthermore, these VH genes generally diversify (duplicate and diverge within a species. Conclusion As in ratfish

  3. Standardization of a two-step real-time polymerase chain reaction based method for species-specific detection of medically important Aspergillus species.

    Science.gov (United States)

    Das, P; Pandey, P; Harishankar, A; Chandy, M; Bhattacharya, S; Chakrabarti, A

    2017-01-01

    Standardization of Aspergillus polymerase chain reaction (PCR) poses two technical challenges (a) standardization of DNA extraction, (b) optimization of PCR against various medically important Aspergillus species. Many cases of aspergillosis go undiagnosed because of relative insensitivity of conventional diagnostic methods such as microscopy, culture or antigen detection. The present study is an attempt to standardize real-time PCR assay for rapid sensitive and specific detection of Aspergillus DNA in EDTA whole blood. Three nucleic acid extraction protocols were compared and a two-step real-time PCR assay was developed and validated following the recommendations of the European Aspergillus PCR Initiative in our setup. In the first PCR step (pan-Aspergillus PCR), the target was 28S rDNA gene, whereas in the second step, species specific PCR the targets were beta-tubulin (for Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus), gene and calmodulin gene (for Aspergillus niger). Species specific identification of four medically important Aspergillus species, namely, A. fumigatus, A. flavus, A. niger and A. terreus were achieved by this PCR. Specificity of the PCR was tested against 34 different DNA source including bacteria, virus, yeast, other Aspergillus sp., other fungal species and for human DNA and had no false-positive reactions. The analytical sensitivity of the PCR was found to be 102 CFU/ml. The present protocol of two-step real-time PCR assays for genus- and species-specific identification for commonly isolated species in whole blood for diagnosis of invasive Aspergillus infections offers a rapid, sensitive and specific assay option and requires clinical validation at multiple centers.

  4. Impact of a 3-Months Vegetarian Diet on the Gut Microbiota and Immune Repertoire

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    Chenchen Zhang

    2018-04-01

    Full Text Available The dietary pattern can influence the immune system directly, but may also modulate it indirectly by regulating the gut microbiota. Here, we investigated the effect of a 3-months lacto-ovo-vegetarian diet on the diversity of gut microbiota and the immune system in healthy omnivorous volunteers, using high-throughput sequencing technologies. The short-term vegetarian diet did not have any major effect on the diversity of the immune system and the overall composition of the metagenome. The prevalence of bacterial genera/species with known beneficial effects on the intestine, including butyrate-producers and probiotic species and the balance of autoimmune-related variable genes/families were, however, altered in the short-term vegetarians. A number of bacterial species that are associated with the expression level of IgA, a key immunoglobulin class that protects the gastrointestinal mucosal system, were also identified. Furthermore, a lower diversity of T-cell repertoire and expression level of IgE, as well as a reduced abundance of inflammation-related genes in the gut microbiota were potentially associated with a control group with long-term vegetarians. Thus, the composition and duration of the diet may have an impact on the balance of pro-/anti-inflammatory factors in the gut microbiota and immune system.

  5. Statistical inference of the generation probability of T-cell receptors from sequence repertoires.

    Science.gov (United States)

    Murugan, Anand; Mora, Thierry; Walczak, Aleksandra M; Callan, Curtis G

    2012-10-02

    Stochastic rearrangement of germline V-, D-, and J-genes to create variable coding sequence for certain cell surface receptors is at the origin of immune system diversity. This process, known as "VDJ recombination", is implemented via a series of stochastic molecular events involving gene choices and random nucleotide insertions between, and deletions from, genes. We use large sequence repertoires of the variable CDR3 region of human CD4+ T-cell receptor beta chains to infer the statistical properties of these basic biochemical events. Because any given CDR3 sequence can be produced in multiple ways, the probability distribution of hidden recombination events cannot be inferred directly from the observed sequences; we therefore develop a maximum likelihood inference method to achieve this end. To separate the properties of the molecular rearrangement mechanism from the effects of selection, we focus on nonproductive CDR3 sequences in T-cell DNA. We infer the joint distribution of the various generative events that occur when a new T-cell receptor gene is created. We find a rich picture of correlation (and absence thereof), providing insight into the molecular mechanisms involved. The generative event statistics are consistent between individuals, suggesting a universal biochemical process. Our probabilistic model predicts the generation probability of any specific CDR3 sequence by the primitive recombination process, allowing us to quantify the potential diversity of the T-cell repertoire and to understand why some sequences are shared between individuals. We argue that the use of formal statistical inference methods, of the kind presented in this paper, will be essential for quantitative understanding of the generation and evolution of diversity in the adaptive immune system.

  6. Molecular evolution of the keratin associated protein gene family in mammals, role in the evolution of mammalian hair.

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    Wu, Dong-Dong; Irwin, David M; Zhang, Ya-Ping

    2008-08-23

    Hair is unique to mammals. Keratin associated proteins (KRTAPs), which contain two major groups: high/ultrahigh cysteine and high glycine-tyrosine, are one of the major components of hair and play essential roles in the formation of rigid and resistant hair shafts. The KRTAP family was identified as being unique to mammals, and near-complete KRTAP gene repertoires for eight mammalian genomes were characterized in this study. An expanded KRTAP gene repertoire was found in rodents. Surprisingly, humans have a similar number of genes as other primates despite the relative hairlessness of humans. We identified several new subfamilies not previously reported in the high/ultrahigh cysteine KRTAP genes. Genes in many subfamilies of the high/ultrahigh cysteine KRTAP genes have evolved by concerted evolution with frequent gene conversion events, yielding a higher GC base content for these gene sequences. In contrast, the high glycine-tyrosine KRTAP genes have evolved more dynamically, with fewer gene conversion events and thus have a lower GC base content, possibly due to positive selection. Most of the subfamilies emerged early in the evolution of mammals, thus we propose that the mammalian ancestor should have a diverse KRTAP gene repertoire. We propose that hair content characteristics have evolved and diverged rapidly among mammals because of rapid divergent evolution of KRTAPs between species. In contrast, subfamilies of KRTAP genes have been homogenized within each species due to concerted evolution.

  7. OXA-258 from Achromobacter ruhlandii: a Species Specific Marker

    OpenAIRE

    Papalia, Mariana Andrea; Almuzara, Marisa; Cejas, Daniela; Traglia, German Matias; Ramirez, Maria Soledad; Galanternik, Laura; Vay, Carlos Alberto; Gutkind, Gabriel Osvaldo; Radice, Marcela Alejandra

    2015-01-01

    A new blaOXA-258 gene is described as species specific taxonomic marker for Achromobacter ruhlandii isolates (all recovered from cystic fibrosis patients). Even if the OXA-258 differs from OXA-114 variants, isolates could be misidentified as A. xiloxosidans by the amplification of an inner fragment from the OXA coding gene. A robust Identification of A. ruhlandii can be achieved by sequencing this single OXA gene as well as a more laborious recently proposed MLST scheme Fil: Papalia, Maria...

  8. Towards the identification of flower-specific genes in Citrus spp

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    Marcelo Carnier Dornelas

    2007-01-01

    Full Text Available Citrus sinensis is a perennial woody species, for which genetic approaches to the study of reproductive development are not readily amenable. Here, the usefulness of the CitEST Expressed Sequence Tag (EST database is demonstrated as a reliable new resource for identifying novel genes exclusively related to Citrus reproductive biology. We performed the analysis of an EST dataset of the CitEST Project containing 4,330 flower-derived cDNA sequences. Relying on bioinformatics tools, sequences exclusively present in this flower-derived sequence collection were selected and used for the identification of Citrus putative flower-specific genes. Our analysis revealed several Citrus sequences showing significant similarity to conserved genes known to have flower-specific expression and possessing functions related to flower metabolism and/or reproductive development in diverse plant species. Comparison of the Citrus flower-specific sequences with all available plant peptide sequences unraveled 247 unique transcripts not identified elsewhere within the plant kingdom. Additionally, 49 transcripts, for which no biological function could be attributed by means of sequence comparisons, were found to be conserved among plant species. These results allow further gene expression analysis and possibly novel approaches to the understanding of reproductive development in Citrus.

  9. Evolutionary Trails of Plant Group II Pyridoxal Phosphate-Dependent Decarboxylase Genes.

    Science.gov (United States)

    Kumar, Rahul

    2016-01-01

    Type II pyridoxal phosphate-dependent decarboxylase (PLP_deC) enzymes play important metabolic roles during nitrogen metabolism. Recent evolutionary profiling of these genes revealed a sharp expansion of histidine decarboxylase genes in the members of Solanaceae family. In spite of the high sequence homology shared by PLP_deC orthologs, these enzymes display remarkable differences in their substrate specificities. Currently, limited information is available on the gene repertoires and substrate specificities of PLP_deCs which renders their precise annotation challenging and offers technical challenges in the immediate identification and biochemical characterization of their full gene complements in plants. Herein, we explored their evolutionary trails in a comprehensive manner by taking advantage of high-throughput data accessibility and computational approaches. We discussed the premise that has enabled an improved reconstruction of their evolutionary lineage and evaluated the factors offering constraints in their rapid functional characterization, till date. We envisage that the synthesized information herein would act as a catalyst for the rapid exploration of their biochemical specificity and physiological roles in more plant species.

  10. The evolutionary history of bears is characterized by gene flow across species

    Science.gov (United States)

    Kumar, Vikas; Lammers, Fritjof; Bidon, Tobias; Pfenninger, Markus; Kolter, Lydia; Nilsson, Maria A.; Janke, Axel

    2017-01-01

    Bears are iconic mammals with a complex evolutionary history. Natural bear hybrids and studies of few nuclear genes indicate that gene flow among bears may be more common than expected and not limited to polar and brown bears. Here we present a genome analysis of the bear family with representatives of all living species. Phylogenomic analyses of 869 mega base pairs divided into 18,621 genome fragments yielded a well-resolved coalescent species tree despite signals for extensive gene flow across species. However, genome analyses using different statistical methods show that gene flow is not limited to closely related species pairs. Strong ancestral gene flow between the Asiatic black bear and the ancestor to polar, brown and American black bear explains uncertainties in reconstructing the bear phylogeny. Gene flow across the bear clade may be mediated by intermediate species such as the geographically wide-spread brown bears leading to large amounts of phylogenetic conflict. Genome-scale analyses lead to a more complete understanding of complex evolutionary processes. Evidence for extensive inter-specific gene flow, found also in other animal species, necessitates shifting the attention from speciation processes achieving genome-wide reproductive isolation to the selective processes that maintain species divergence in the face of gene flow. PMID:28422140

  11. The evolutionary history of bears is characterized by gene flow across species.

    Science.gov (United States)

    Kumar, Vikas; Lammers, Fritjof; Bidon, Tobias; Pfenninger, Markus; Kolter, Lydia; Nilsson, Maria A; Janke, Axel

    2017-04-19

    Bears are iconic mammals with a complex evolutionary history. Natural bear hybrids and studies of few nuclear genes indicate that gene flow among bears may be more common than expected and not limited to polar and brown bears. Here we present a genome analysis of the bear family with representatives of all living species. Phylogenomic analyses of 869 mega base pairs divided into 18,621 genome fragments yielded a well-resolved coalescent species tree despite signals for extensive gene flow across species. However, genome analyses using different statistical methods show that gene flow is not limited to closely related species pairs. Strong ancestral gene flow between the Asiatic black bear and the ancestor to polar, brown and American black bear explains uncertainties in reconstructing the bear phylogeny. Gene flow across the bear clade may be mediated by intermediate species such as the geographically wide-spread brown bears leading to large amounts of phylogenetic conflict. Genome-scale analyses lead to a more complete understanding of complex evolutionary processes. Evidence for extensive inter-specific gene flow, found also in other animal species, necessitates shifting the attention from speciation processes achieving genome-wide reproductive isolation to the selective processes that maintain species divergence in the face of gene flow.

  12. Evolutionary origins of Brassicaceae specific genes in Arabidopsis thaliana

    Science.gov (United States)

    2011-01-01

    Background All sequenced genomes contain a proportion of lineage-specific genes, which exhibit no sequence similarity to any genes outside the lineage. Despite their prevalence, the origins and functions of most lineage-specific genes remain largely unknown. As more genomes are sequenced opportunities for understanding evolutionary origins and functions of lineage-specific genes are increasing. Results This study provides a comprehensive analysis of the origins of lineage-specific genes (LSGs) in Arabidopsis thaliana that are restricted to the Brassicaceae family. In this study, lineage-specific genes within the nuclear (1761 genes) and mitochondrial (28 genes) genomes are identified. The evolutionary origins of two thirds of the lineage-specific genes within the Arabidopsis thaliana genome are also identified. Almost a quarter of lineage-specific genes originate from non-lineage-specific paralogs, while the origins of ~10% of lineage-specific genes are partly derived from DNA exapted from transposable elements (twice the proportion observed for non-lineage-specific genes). Lineage-specific genes are also enriched in genes that have overlapping CDS, which is consistent with such novel genes arising from overprinting. Over half of the subset of the 958 lineage-specific genes found only in Arabidopsis thaliana have alignments to intergenic regions in Arabidopsis lyrata, consistent with either de novo origination or differential gene loss and retention, with both evolutionary scenarios explaining the lineage-specific status of these genes. A smaller number of lineage-specific genes with an incomplete open reading frame across different Arabidopsis thaliana accessions are further identified as accession-specific genes, most likely of recent origin in Arabidopsis thaliana. Putative de novo origination for two of the Arabidopsis thaliana-only genes is identified via additional sequencing across accessions of Arabidopsis thaliana and closely related sister species

  13. Different Somatic Hypermutation Levels among Antibody Subclasses Disclosed by a New Next-Generation Sequencing-Based Antibody Repertoire Analysis

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    Kazutaka Kitaura

    2017-05-01

    Full Text Available A diverse antibody repertoire is primarily generated by the rearrangement of V, D, and J genes and subsequent somatic hypermutation (SHM. Class-switch recombination (CSR produces various isotypes and subclasses with different functional properties. Although antibody isotypes and subclasses are considered to be produced by both direct and sequential CSR, it is still not fully understood how SHMs accumulate during the process in which antibody subclasses are generated. Here, we developed a new next-generation sequencing (NGS-based antibody repertoire analysis capable of identifying all antibody isotype and subclass genes and used it to examine the peripheral blood mononuclear cells of 12 healthy individuals. Using a total of 5,480,040 sequences, we compared percentage frequency of variable (V, junctional (J sequence, and a combination of V and J, diversity, length, and amino acid compositions of CDR3, SHM, and shared clones in the IgM, IgD, IgG3, IgG1, IgG2, IgG4, IgA1, IgE, and IgA2 genes. The usage and diversity were similar among the immunoglobulin (Ig subclasses. Clonally related sequences sharing identical V, D, J, and CDR3 amino acid sequences were frequently found within multiple Ig subclasses, especially between IgG1 and IgG2 or IgA1 and IgA2. SHM occurred most frequently in IgG4, while IgG3 genes were the least mutated among all IgG subclasses. The shared clones had almost the same SHM levels among Ig subclasses, while subclass-specific clones had different levels of SHM dependent on the genomic location. Given the sequential CSR, these results suggest that CSR occurs sequentially over multiple subclasses in the order corresponding to the genomic location of IGHCs, but CSR is likely to occur more quickly than SHMs accumulate within Ig genes under physiological conditions. NGS-based antibody repertoire analysis should provide critical information on how various antibodies are generated in the immune system.

  14. Fine-scale genetic analysis of species-specific female preference in Drosophila simulans.

    Science.gov (United States)

    Laturney, M; Moehring, A J

    2012-09-01

    Behavioural differences are thought to be the first components to contribute to species isolation, yet the precise genetic basis of behavioural isolation remains poorly understood. Here, we used a combination of behaviour assays and genetic mapping to provide the first refined map locating candidate genes for interspecific female preference isolating Drosophila simulans from D. melanogaster. First, we tested whether two genes identified as affecting D. melanogaster female intraspecific mate choice also affect interspecific mate choice; neither of these genes was found to contribute to species-specific female preference. Next, we used deficiency mapping to locate genes on the right arm of the third chromosome for species-specific female preference and identified five small significant regions that contain candidate genes contributing to behavioural isolation. All five regions were located in areas that would have low interspecific recombination, which mirrors the results of other behavioural isolation studies that used quantitative trait locus (QTL) mapping, but without the potential concern of bias towards regions of low recombination that QTL mapping may have. As this model system may be refined to the individual gene level using the same methodology, this initial map we provide may potentially serve as a ready template for the identification and characterization of the first behavioural isolation genes. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

  15. B cell and antibody repertoire development in rabbits: the requirement of gut-associated lymphoid tissues.

    Science.gov (United States)

    Mage, Rose G; Lanning, Dennis; Knight, Katherine L

    2006-01-01

    The antibody repertoire of rabbits has interested immunologists for decades, in part because of the ease with which large quantities of high affinity antibodies can be obtained in serum, and in part because of the presence of genetic variants, allotypes, within V(H), C(H) and C(L) regions. Studies of these allotypes led to the initial descriptions of allelic exclusion, and neonatal suppression of serum Ig production (allotype suppression), and were instrumental in demonstrating that V and C regions are encoded by separate genes and are usually expressed in cis. The immune system of rabbit continues to be of interest primarily because of the use of both gene conversion and somatic hypermutation to diversify rearranged heavy and light chain genes and the role that gut-associated lymphoid tissues (GALT) and intestinal flora play in developing the primary (preimmune) antibody repertoire.

  16. Simultaneous discrimination of species and strains in Lactobacillus rhamnosus using species-specific PCR combined with multiplex mini-sequencing technology.

    Science.gov (United States)

    Huang, Chien-Hsun; Chang, Mu-Tzu; Huang, Lina; Chu, Wen-Shen

    2015-12-01

    This study described the use of species-specific PCR in combination with SNaPshot mini-sequencing to achieve species identification and strain differentiation in Lactobacillus rhamnosus. To develop species-specific PCR and strain subtyping primers, the dnaJ gene was used as a target, and its corresponding sequences were analyzed both in Lb. rhamnosus and in a subset of its phylogenetically closest species. The results indicated that the species-specific primer pair was indeed specific for Lb. rhamnosus, and the mini-sequencing assay was able to unambiguously distinguish Lb. rhamnosus strains into different haplotypes. In conclusion, we have successfully developed a rapid, accurate and cost-effective assay for inter- and intraspecies discrimination of Lb. rhamnosus, which can be applied to achieve efficient quality control of probiotic products. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Genes expressed in specific areas of the human fetal cerebral cortex display distinct patterns of evolution.

    Directory of Open Access Journals (Sweden)

    Nelle Lambert

    2011-03-01

    Full Text Available The developmental mechanisms through which the cerebral cortex increased in size and complexity during primate evolution are essentially unknown. To uncover genetic networks active in the developing cerebral cortex, we combined three-dimensional reconstruction of human fetal brains at midgestation and whole genome expression profiling. This novel approach enabled transcriptional characterization of neurons from accurately defined cortical regions containing presumptive Broca and Wernicke language areas, as well as surrounding associative areas. We identified hundreds of genes displaying differential expression between the two regions, but no significant difference in gene expression between left and right hemispheres. Validation by qRTPCR and in situ hybridization confirmed the robustness of our approach and revealed novel patterns of area- and layer-specific expression throughout the developing cortex. Genes differentially expressed between cortical areas were significantly associated with fast-evolving non-coding sequences harboring human-specific substitutions that could lead to divergence in their repertoires of transcription factor binding sites. Strikingly, while some of these sequences were accelerated in the human lineage only, many others were accelerated in chimpanzee and/or mouse lineages, indicating that genes important for cortical development may be particularly prone to changes in transcriptional regulation across mammals. Genes differentially expressed between cortical regions were also enriched for transcriptional targets of FoxP2, a key gene for the acquisition of language abilities in humans. Our findings point to a subset of genes with a unique combination of cortical areal expression and evolutionary patterns, suggesting that they play important roles in the transcriptional network underlying human-specific neural traits.

  18. Unusual evolutionary conservation and further species-specific adaptations of a large family of nonclassical MHC class Ib genes across different degrees of genome ploidy in the amphibian subfamily Xenopodinae.

    Science.gov (United States)

    Edholm, Eva-Stina; Goyos, Ana; Taran, Joseph; De Jesús Andino, Francisco; Ohta, Yuko; Robert, Jacques

    2014-06-01

    Nonclassical MHC class Ib (class Ib) genes are a family of highly diverse and rapidly evolving genes wherein gene numbers, organization, and expression markedly differ even among closely related species rendering class Ib phylogeny difficult to establish. Whereas among mammals there are few unambiguous class Ib gene orthologs, different amphibian species belonging to the anuran subfamily Xenopodinae exhibit an unusually high degree of conservation among multiple class Ib gene lineages. Comparative genomic analysis of class Ib gene loci of two divergent (~65 million years) Xenopodinae subfamily members Xenopus laevis (allotetraploid) and Xenopus tropicalis (diploid) shows that both species possess a large cluster of class Ib genes denoted as Xenopus/Silurana nonclassical (XNC/SNC). Our study reveals two distinct phylogenetic patterns among these genes: some gene lineages display a high degree of flexibility, as demonstrated by species-specific expansion and contractions, whereas other class Ib gene lineages have been maintained as monogenic subfamilies with very few changes in their nucleotide sequence across divergent species. In this second category, we further investigated the XNC/SNC10 gene lineage that in X. laevis is required for the development of a distinct semi-invariant T cell population. We report compelling evidence of the remarkable high degree of conservation of this gene lineage that is present in all 12 species of the Xenopodinae examined, including species with different degrees of ploidy ranging from 2, 4, 8 to 12 N. This suggests that the critical role of XNC10 during early T cell development is conserved in amphibians.

  19. Transcription Factor Repertoire of Necrotrophic Fungal Phytopathogen Ascochyta rabiei: Predominance of MYB Transcription Factors As Potential Regulators of Secretome

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    Sandhya Verma

    2017-06-01

    Full Text Available Transcription factors (TFs are the key players in gene expression and their study is highly significant for shedding light on the molecular mechanisms and evolutionary history of organisms. During host–pathogen interaction, extensive reprogramming of gene expression facilitated by TFs is likely to occur in both host and pathogen. To date, the knowledge about TF repertoire in filamentous fungi is in infancy. The necrotrophic fungus Ascochyta rabiei, that causes destructive Ascochyta blight (AB disease of chickpea (Cicer arietinum, demands more comprehensive study for better understanding of Ascochyta-legume pathosystem. In the present study, we performed the genome-wide identification and analysis of TFs in A. rabiei. Taking advantage of A. rabiei genome sequence, we used a bioinformatic approach to predict the TF repertoire of A. rabiei. For identification and classification of A. rabiei TFs, we designed a comprehensive pipeline using a combination of BLAST and InterProScan software. A total of 381 A. rabiei TFs were predicted and divided into 32 fungal specific families of TFs. The gene structure, domain organization and phylogenetic analysis of abundant families of A. rabiei TFs were also carried out. Comparative study of A. rabiei TFs with that of other necrotrophic, biotrophic, hemibiotrophic, symbiotic, and saprotrophic fungi was performed. It suggested presence of both conserved as well as unique features among them. Moreover, cis-acting elements on promoter sequences of earlier predicted A. rabiei secretome were also identified. With the help of published A. rabiei transcriptome data, the differential expression of TF and secretory protein coding genes was analyzed. Furthermore, comprehensive expression analysis of few selected A. rabiei TFs using quantitative real-time polymerase chain reaction revealed variety of expression patterns during host colonization. These genes were expressed in at least one of the time points tested post

  20. The artiodactyl APOBEC3 innate immune repertoire shows evidence for a multi-functional domain organization that existed in the ancestor of placental mammals

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    Andrésdóttir Valgerdur

    2008-11-01

    Full Text Available Abstract Background APOBEC3 (A3 proteins deaminate DNA cytosines and block the replication of retroviruses and retrotransposons. Each A3 gene encodes a protein with one or two conserved zinc-coordinating motifs (Z1, Z2 or Z3. The presence of one A3 gene in mice (Z2–Z3 and seven in humans, A3A-H (Z1a, Z2a-Z1b, Z2b, Z2c-Z2d, Z2e-Z2f, Z2g-Z1c, Z3, suggests extraordinary evolutionary flexibility. To gain insights into the mechanism and timing of A3 gene expansion and into the functional modularity of these genes, we analyzed the genomic sequences, expressed cDNAs and activities of the full A3 repertoire of three artiodactyl lineages: sheep, cattle and pigs. Results Sheep and cattle have three A3 genes, A3Z1, A3Z2 and A3Z3, whereas pigs only have two, A3Z2 and A3Z3. A comparison between domestic and wild pigs indicated that A3Z1 was deleted in the pig lineage. In all three species, read-through transcription and alternative splicing also produced a catalytically active double domain A3Z2-Z3 protein that had a distinct cytoplasmic localization. Thus, the three A3 genes of sheep and cattle encode four conserved and active proteins. These data, together with phylogenetic analyses, indicated that a similar, functionally modular A3 repertoire existed in the common ancestor of artiodactyls and primates (i.e., the ancestor of placental mammals. This mammalian ancestor therefore possessed the minimal A3 gene set, Z1-Z2-Z3, required to evolve through a remarkable series of eight recombination events into the present day eleven Z domain human repertoire. Conclusion The dynamic recombination-filled history of the mammalian A3 genes is consistent with the modular nature of the locus and a model in which most of these events (especially the expansions were selected by ancient pathogenic retrovirus infections.

  1. Rules of song development and their use in vocal interactions by birds with large repertoires

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    Nicole Geberzahn

    2004-06-01

    Full Text Available Songbirds are well known for settling their disputes by vocal signals, and their singing plays a dominant role. Most studies on this issue have concentrated on bird species that develop and use small vocal repertoires. In this article we will go farther and focus on examples of how species with large song repertoires make use of their vocal competence. In particular, we will outline the study of interaction rules which have been elucidated by examining time- and pattern-specific relationships between signals exchanged by territorial neighbors. First we present an inquiry into the rules of song learning and development. In birds with large song repertoires, the ontogeny of such rules proceeds along a number of trajectories which help in understanding the often remarkable accomplishments of adult birds. In both approaches, our model species will be the Common Nightingale Luscinia megarhynchos that has been investigated intensively in the field and in the laboratory.Pássaros canoros são bem conhecidos por resolver suas brigas através de sinais vocais e seu canto tem um papel dominante. A maioria dos estudos sobre este assunto focalizou espécies de aves que desenvolvem e usam repertórios vocais pequenos. Neste artigo iremos mais longe, examinando como espécies com grandes repertórios fazem uso de suas capacidades. Descreveremos particularmente o estudo das regras de interação que foram desvendadas pelo exame das relações temporais e estruturais entre os sinais trocados por vizinhos. Inicialmente, investigamos as regras de aprendizagem e desenvolvimento do canto. Nas aves com grande repertório vocal, a ontogênese dessas regras segue certas trajetórias que ajudam a entender o desempenho dos adultos, geralmente notável. Em ambas abordagens, nossa espécie-modelo será o Rouxinol-comum Luscinia megarhynchos, que foi pesquisado intensamente no campo e no laboratório.

  2. Antibody repertoire profiling with mimotope arrays

    OpenAIRE

    Pashova, Shina; Schneider, Christoph; von Gunten, Stephan; Pashov, Anastas

    2016-01-01

    Large-scale profiling and monitoring of antibody repertoires is possible through next generation sequencing (NGS), phage display libraries and microarrays. These methods can be combined in a pipeline, which ultimately maps the antibody reactivities onto defined arrays of structures - peptides or carbohydrates. The arrays can help analyze the individual specificities or can be used as complex patterns. In any case, the targets recognized should formally be considered mimotopes unless they are ...

  3. Accurate and High-Coverage Immune Repertoire Sequencing Reveals Characteristics of Antibody Repertoire Diversification in Young Children with Malaria

    Science.gov (United States)

    Jiang, Ning

    Accurately measuring the immune repertoire sequence composition, diversity, and abundance is important in studying repertoire response in infections, vaccinations, and cancer immunology. Using molecular identifiers (MIDs) to tag mRNA molecules is an effective method in improving the accuracy of immune repertoire sequencing (IR-seq). However, it is still difficult to use IR-seq on small amount of clinical samples to achieve a high coverage of the repertoire diversities. This is especially challenging in studying infections and vaccinations where B cell subpopulations with fewer cells, such as memory B cells or plasmablasts, are often of great interest to study somatic mutation patterns and diversity changes. Here, we describe an approach of IR-seq based on the use of MIDs in combination with a clustering method that can reveal more than 80% of the antibody diversity in a sample and can be applied to as few as 1,000 B cells. We applied this to study the antibody repertoires of young children before and during an acute malaria infection. We discovered unexpectedly high levels of somatic hypermutation (SHM) in infants and revealed characteristics of antibody repertoire development in young children that would have a profound impact on immunization in children.

  4. The function and evolution of Wnt genes in arthropods.

    Science.gov (United States)

    Murat, Sophie; Hopfen, Corinna; McGregor, Alistair P

    2010-11-01

    Wnt signalling is required for a wide range of developmental processes, from cleavage to patterning and cell migration. There are 13 subfamilies of Wnt ligand genes and this diverse repertoire appeared very early in metazoan evolution. In this review, we first summarise the known Wnt gene repertoire in various arthropods. Insects appear to have lost several Wnt subfamilies, either generally, such as Wnt3, or in lineage specific patterns, for example, the loss of Wnt7 in Anopheles. In Drosophila and Acyrthosiphon, only seven and six Wnt subfamilies are represented, respectively; however, the finding of nine Wnt genes in Tribolium suggests that arthropods had a larger repertoire ancestrally. We then discuss what is currently known about the expression and developmental function of Wnt ligands in Drosophila and other insects in comparison to other arthropods, such as the spiders Achaearanea and Cupiennius. We conclude that studies of Wnt genes have given us much insight into the developmental roles of some of these ligands. However, given the frequent loss of Wnt genes in insects and the derived development of Drosophila, further studies of these important genes are required in a broader range of arthropods to fully understand their developmental function and evolution. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. The MicroRNA Repertoire of Symbiodinium, the Dinoflagellate Symbiont of Reef-Building Corals

    KAUST Repository

    Baumgarten, Sebastian

    2013-07-01

    Animal and plant genomes produce numerous small RNAs (smRNAs) that regulate gene expression post-transcriptionally affecting metabolism, development, and epigenetic inheritance. In order to characterize the repertoire of endogenous microRNAs and potential gene targets, we conducted smRNA and mRNA expression profiling over nine experimental treatments of cultures from the dinoflagellate Symbiodinium sp. A1, a photosynthetic symbiont of scleractinian corals. We identified a total of 75 novel smRNAs in Symbiodinum sp. A1 that share stringent key features with functional microRNAs from other model organisms. A subset of 38 smRNAs was predicted independently over all nine treatments and their putative gene targets were identified. We found 3,187 animal-like target sites in the 3’UTRs of 12,858 mRNAs and 53 plantlike target sites in 51,917 genes. Furthermore, we identified the core RNAi protein machinery in Symbiodinium. Integration of smRNA and mRNA expression profiling identified a variety of processes that could be under microRNA control, e.g. regulation of translation, DNA modification, and chromatin silencing. Given that Symbiodinium seems to have a paucity of transcription factors and differentially expressed genes, identification and characterization of its smRNA repertoire establishes the possibility of a range of gene regulatory mechanisms in dinoflagellates acting post-transcriptionally.

  6. Mating type genes in the genus Neofusicoccum: Mating strategies and usefulness in species delimitation.

    Science.gov (United States)

    Lopes, Anabela; Phillips, Alan J L; Alves, Artur

    2017-04-01

    The genus Neofusicoccum includes species with wide geographical and plant host distribution, some of them of economic importance. The genus currently comprises 27 species that are difficult to identify based on morphological features alone. Thus, species differentiation is based on phylogenetic species recognition using multigene genealogies. In this study, we characterised the mating type genes of Neofusicoccum species. Specific primers were designed to amplify and sequence MAT genes in several species and a PCR-based mating type diagnostic assay was developed. Homothallism was the predominant mating strategy among the species tested. Furthermore, the potential of mating type gene sequences for species delimitation was evaluated. Phylogenetic analyses were performed on both MAT genes and compared with multigene genealogies using sequences of the ribosomal internal transcribed spacer region, translation elongation factor 1-alpha and beta-tubulin. Phylogenies based on mating type genes could discriminate between the species analysed and are in concordance with the results obtained with the more conventional multilocus phylogenetic analysis approach. Thus, MAT genes represent a powerful tool to delimit cryptic species in the genus Neofusicoccum. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  7. The immune gene repertoire of an important viral reservoir, the Australian black flying fox

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    Papenfuss Anthony T

    2012-06-01

    Full Text Available Abstract Background Bats are the natural reservoir host for a range of emerging and re-emerging viruses, including SARS-like coronaviruses, Ebola viruses, henipaviruses and Rabies viruses. However, the mechanisms responsible for the control of viral replication in bats are not understood and there is little information available on any aspect of antiviral immunity in bats. Massively parallel sequencing of the bat transcriptome provides the opportunity for rapid gene discovery. Although the genomes of one megabat and one microbat have now been sequenced to low coverage, no transcriptomic datasets have been reported from any bat species. In this study, we describe the immune transcriptome of the Australian flying fox, Pteropus alecto, providing an important resource for identification of genes involved in a range of activities including antiviral immunity. Results Towards understanding the adaptations that have allowed bats to coexist with viruses, we have de novo assembled transcriptome sequence from immune tissues and stimulated cells from P. alecto. We identified about 18,600 genes involved in a broad range of activities with the most highly expressed genes involved in cell growth and maintenance, enzyme activity, cellular components and metabolism and energy pathways. 3.5% of the bat transcribed genes corresponded to immune genes and a total of about 500 immune genes were identified, providing an overview of both innate and adaptive immunity. A small proportion of transcripts found no match with annotated sequences in any of the public databases and may represent bat-specific transcripts. Conclusions This study represents the first reported bat transcriptome dataset and provides a survey of expressed bat genes that complement existing bat genomic data. In addition, these data provide insight into genes relevant to the antiviral responses of bats, and form a basis for examining the roles of these molecules in immune response to viral infection.

  8. Immune Repertoire after Immunization As Seen by Next-Generation Sequencing and Proteomics

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    Martijn M. VanDuijn

    2017-10-01

    Full Text Available The immune system produces a diverse repertoire of immunoglobulins in response to foreign antigens. During B-cell development, VDJ recombination and somatic mutations generate diversity, whereas selection processes remove it. Using both proteomic and NGS approaches, we characterized the immune repertoires in groups of rats after immunization with purified antigens. Proteomics and NGS data on the repertoire are in qualitative agreement, but did show quantitative differences that may relate to differences between the biological niches that were sampled for these approaches. Both methods contributed complementary information in the characterization of the immune repertoire. It was found that the immune repertoires resulting from each antigen had many similarities that allowed samples to cluster together, and that mutated immunoglobulin peptides were shared among animals with a response to the same antigen significantly more than for different antigens. However, the number of shared sequences decreased in a log-linear fashion relative to the number of animals that share them, which may affect future applications. A phylogenetic analysis on the NGS reads showed that reads from different individuals immunized with the same antigen populated distinct branches of the phylogram, an indication that the repertoire had converged. Also, similar mutation patterns were found in branches of the phylogenetic tree that were associated with antigen-specific immunoglobulins through proteomics data. Thus, data from different analysis methods and different experimental platforms show that the immunoglobulin repertoires of immunized animals have overlapping and converging features. With additional research, this may enable interesting applications in biotechnology and clinical diagnostics.

  9. In silico peptide-binding predictions of passerine MHC class I reveal similarities across distantly related species, suggesting convergence on the level of protein function.

    Science.gov (United States)

    Follin, Elna; Karlsson, Maria; Lundegaard, Claus; Nielsen, Morten; Wallin, Stefan; Paulsson, Kajsa; Westerdahl, Helena

    2013-04-01

    The major histocompatibility complex (MHC) genes are the most polymorphic genes found in the vertebrate genome, and they encode proteins that play an essential role in the adaptive immune response. Many songbirds (passerines) have been shown to have a large number of transcribed MHC class I genes compared to most mammals. To elucidate the reason for this large number of genes, we compared 14 MHC class I alleles (α1-α3 domains), from great reed warbler, house sparrow and tree sparrow, via phylogenetic analysis, homology modelling and in silico peptide-binding predictions to investigate their functional and genetic relationships. We found more pronounced clustering of the MHC class I allomorphs (allele specific proteins) in regards to their function (peptide-binding specificities) compared to their genetic relationships (amino acid sequences), indicating that the high number of alleles is of functional significance. The MHC class I allomorphs from house sparrow and tree sparrow, species that diverged 10 million years ago (MYA), had overlapping peptide-binding specificities, and these similarities across species were also confirmed in phylogenetic analyses based on amino acid sequences. Notably, there were also overlapping peptide-binding specificities in the allomorphs from house sparrow and great reed warbler, although these species diverged 30 MYA. This overlap was not found in a tree based on amino acid sequences. Our interpretation is that convergent evolution on the level of the protein function, possibly driven by selection from shared pathogens, has resulted in allomorphs with similar peptide-binding repertoires, although trans-species evolution in combination with gene conversion cannot be ruled out.

  10. Multi-species sequence comparison reveals dynamic evolution of the elastin gene that has involved purifying selection and lineage-specific insertions/deletions

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    Green Eric D

    2004-05-01

    Full Text Available Abstract Background The elastin gene (ELN is implicated as a factor in both supravalvular aortic stenosis (SVAS and Williams Beuren Syndrome (WBS, two diseases involving pronounced complications in mental or physical development. Although the complete spectrum of functional roles of the processed gene product remains to be established, these roles are inferred to be analogous in human and mouse. This view is supported by genomic sequence comparison, in which there are no large-scale differences in the ~1.8 Mb sequence block encompassing the common region deleted in WBS, with the exception of an overall reversed physical orientation between human and mouse. Results Conserved synteny around ELN does not translate to a high level of conservation in the gene itself. In fact, ELN orthologs in mammals show more sequence divergence than expected for a gene with a critical role in development. The pattern of divergence is non-conventional due to an unusually high ratio of gaps to substitutions. Specifically, multi-sequence alignments of eight mammalian sequences reveal numerous non-aligning regions caused by species-specific insertions and deletions, in spite of the fact that the vast majority of aligning sites appear to be conserved and undergoing purifying selection. Conclusions The pattern of lineage-specific, in-frame insertions/deletions in the coding exons of ELN orthologous genes is unusual and has led to unique features of the gene in each lineage. These differences may indicate that the gene has a slightly different functional mechanism in mammalian lineages, or that the corresponding regions are functionally inert. Identified regions that undergo purifying selection reflect a functional importance associated with evolutionary pressure to retain those features.

  11. The polyphenol oxidase gene family in land plants: Lineage-specific duplication and expansion

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    Tran Lan T

    2012-08-01

    Full Text Available Abstract Background Plant polyphenol oxidases (PPOs are enzymes that typically use molecular oxygen to oxidize ortho-diphenols to ortho-quinones. These commonly cause browning reactions following tissue damage, and may be important in plant defense. Some PPOs function as hydroxylases or in cross-linking reactions, but in most plants their physiological roles are not known. To better understand the importance of PPOs in the plant kingdom, we surveyed PPO gene families in 25 sequenced genomes from chlorophytes, bryophytes, lycophytes, and flowering plants. The PPO genes were then analyzed in silico for gene structure, phylogenetic relationships, and targeting signals. Results Many previously uncharacterized PPO genes were uncovered. The moss, Physcomitrella patens, contained 13 PPO genes and Selaginella moellendorffii (spike moss and Glycine max (soybean each had 11 genes. Populus trichocarpa (poplar contained a highly diversified gene family with 11 PPO genes, but several flowering plants had only a single PPO gene. By contrast, no PPO-like sequences were identified in several chlorophyte (green algae genomes or Arabidopsis (A. lyrata and A. thaliana. We found that many PPOs contained one or two introns often near the 3’ terminus. Furthermore, N-terminal amino acid sequence analysis using ChloroP and TargetP 1.1 predicted that several putative PPOs are synthesized via the secretory pathway, a unique finding as most PPOs are predicted to be chloroplast proteins. Phylogenetic reconstruction of these sequences revealed that large PPO gene repertoires in some species are mostly a consequence of independent bursts of gene duplication, while the lineage leading to Arabidopsis must have lost all PPO genes. Conclusion Our survey identified PPOs in gene families of varying sizes in all land plants except in the genus Arabidopsis. While we found variation in intron numbers and positions, overall PPO gene structure is congruent with the phylogenetic

  12. Repertoire of free-living protozoa in contact lens solutions.

    Science.gov (United States)

    Bouchoucha, Ibtissem; Aziz, Aurore; Hoffart, Louis; Drancourt, Michel

    2016-10-29

    The repertoire of free-living protozoa in contact lens solutions is poorly known despite the fact that such protozoa may act as direct pathogens and may harbor intra-cellular pathogens. Between 2009 and 2014, the contact lens solutions collected from patients presenting at our Ophthalmology Department for clinically suspected keratitis, were cultured on non-nutrient agar examined by microscope for the presence of free-living protozoa. All protozoa were identified by 18S rRNA gene sequencing. A total of 20 of 233 (8.6 %) contact lens solution specimens collected from 16 patients were cultured. Acanthamoeba amoeba in 16 solutions (80 %) collected from 12 patients and Colpoda steini, Cercozoa sp., Protostelium sp. and a eukaryotic more closely related to Vermamoeba sp., were each isolated in one solution. Cercozoa sp., Colpoda sp., Protostelium sp. and Vermamoeba sp. are reported for the first time as contaminating contact lens solutions. The repertoire of protozoa in contact lens solutions is larger than previously known.

  13. Specific gene expression responses to parasite genotypes reveal redundancy of innate immunity in vertebrates.

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    David Haase

    Full Text Available Vertebrate innate immunity is the first line of defense against an invading pathogen and has long been assumed to be largely unspecific with respect to parasite/pathogen species. However, recent phenotypic evidence suggests that immunogenetic variation, i.e. allelic variability in genes associated with the immune system, results in host-parasite genotype-by-genotype interactions and thus specific innate immune responses. Immunogenetic variation is common in all vertebrate taxa and this reflects an effective immunological function in complex environments. However, the underlying variability in host gene expression patterns as response of innate immunity to within-species genetic diversity of macroparasites in vertebrates is unknown. We hypothesized that intra-specific variation among parasite genotypes must be reflected in host gene expression patterns. Here we used high-throughput RNA-sequencing to examine the effect of parasite genotypes on gene expression patterns of a vertebrate host, the three-spined stickleback (Gasterosteus aculeatus. By infecting naïve fish with distinct trematode genotypes of the species Diplostomum pseudospathaceum we show that gene activity of innate immunity in three-spined sticklebacks depended on the identity of an infecting macroparasite genotype. In addition to a suite of genes indicative for a general response against the trematode we also find parasite-strain specific gene expression, in particular in the complement system genes, despite similar infection rates of single clone treatments. The observed discrepancy between infection rates and gene expression indicates the presence of alternative pathways which execute similar functions. This suggests that the innate immune system can induce redundant responses specific to parasite genotypes.

  14. Study on Fusion Protein and Its gene in Baculovirus Specificity

    International Nuclear Information System (INIS)

    Nemr, W.A.H.

    2012-01-01

    Baculoviruses are subdivided into two groups depending on the type of budded virus envelop fusion protein; group I utilized gp64 which include the most of nucleopolyhedroviruses (NPVs), group II utilized F protein which include the remnants of NPVs and all Granuloviruses (GVs). Recent studies reported the viral F protein coding gene as a host cellular sourced gene and may evolutionary acquired from the host genome referring to phylogeny analysis of fusion proteins. Thus, it was deduced that F protein coding gene is species- specific nucleotide sequence related to the type of the specific host and if virus could infect an unexpected host, the resulted virus may encode a vary F gene. In this regard, the present study utilized the mentioned properties of F gene in an attempt to produce a model of specific and more economic wider range granulovirus bio- pesticide able to infect both Spodoptera littoralis and Phthorimaea operculella larvae. Multiple sequence alignment and phylogeny analysis were performed on six members of group II baculovirus, novel universal PCR primers were manually designed from the conserved regions in the alignment graph, targeted to amplify species- specific sequence entire F gene open reading frame (ORF) which is useful in molecular identification of baculovirus in unknown samples. So, the PCR product of SpliGV used to prepare a specific probe for the F gene of this type of virus. Results reflected that it is possible to infect S. littoralis larvae by PhopGV if injected into larval haemocoel, the resulted virus of this infection showed by using DNA hybridization technique to be encode to F gene homologous with the F gene of Spli GV, which is revealed that the resulted virus acquired this F gene sequence from the host genome after infection. Consequently, these results may infer that if genetic aberrations occur in the host genome, this may affect in baculoviral infectivity. So, this study aimed to investigate the effect of gamma radiation at

  15. Species- and sex-specific connectivity effects of habitat fragmentation in a suite of woodland birds.

    Science.gov (United States)

    Amos, Nevil; Harrisson, Katherine A; Radford, James Q; White, Matt; Newell, Graeme; Mac Nally, Ralph; Sunnucks, Paul; Pavlova, Alexandra

    2014-06-01

    Loss of functional connectivity following habitat loss and fragmentation could drive species declines. A comprehensive understanding of fragmentation effects on functional connectivity of an ecological assemblage requires investigation of multiple species with different mobilities, at different spatial scales, for each sex, and in different landscapes. Based on published data on mobility and ecological responses to fragmentation of 10 woodland-dependent birds, and using simulation studies, we predicted that (1) fragmentation would impede dispersal and gene flow of eight "decliners" (species that disappear from suitable patches when landscape-level tree cover falls below species-specific thresholds), but not of two "tolerant" species (whose occurrence in suitable habitat patches is independent of landscape tree cover); and that fragmentation effects would be stronger (2) in the least mobile species, (3) in the more philopatric sex, and (4) in the more fragmented region. We tested these predictions by evaluating spatially explicit isolation-by-landscape-resistance models of gene flow in fragmented landscapes across a 50 x 170 km study area in central Victoria, Australia, using individual and population genetic distances. To account for sex-biased dispersal and potential scale- and configuration-specific effects, we fitted models specific to sex and geographic zones. As predicted, four of the least mobile decliners showed evidence of reduced genetic connectivity. The responses were strongly sex specific, but in opposite directions in the two most sedentary species. Both tolerant species and (unexpectedly) four of the more mobile decliners showed no reduction in gene flow. This is unlikely to be due to time lags because more mobile species develop genetic signatures of fragmentation faster than do less mobile ones. Weaker genetic effects were observed in the geographic zone with more aggregated vegetation, consistent with gene flow being unimpeded by landscape

  16. Gaining insights into the codon usage patterns of TP53 gene across eight mammalian species.

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    Tarikul Huda Mazumder

    Full Text Available TP53 gene is known as the "guardian of the genome" as it plays a vital role in regulating cell cycle, cell proliferation, DNA damage repair, initiation of programmed cell death and suppressing tumor growth. Non uniform usage of synonymous codons for a specific amino acid during translation of protein known as codon usage bias (CUB is a unique property of the genome and shows species specific deviation. Analysis of codon usage bias with compositional dynamics of coding sequences has contributed to the better understanding of the molecular mechanism and the evolution of a particular gene. In this study, the complete nucleotide coding sequences of TP53 gene from eight different mammalian species were used for CUB analysis. Our results showed that the codon usage patterns in TP53 gene across different mammalian species has been influenced by GC bias particularly GC3 and a moderate bias exists in the codon usage of TP53 gene. Moreover, we observed that nature has highly favored the most over represented codon CTG for leucine amino acid but selected against the ATA codon for isoleucine in TP53 gene across all mammalian species during the course of evolution.

  17. Rapid male-specific regulatory divergence and down regulation of spermatogenesis genes in Drosophila species hybrids.

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    Jennifer Ferguson

    Full Text Available In most crosses between closely related species of Drosophila, the male hybrids are sterile and show postmeiotic abnormalities. A series of gene expression studies using genomic approaches have found significant down regulation of postmeiotic spermatogenesis genes in sterile male hybrids. These results have led some to suggest a direct relationship between down regulation in gene expression and hybrid sterility. An alternative explanation to a cause-and-effect relationship between misregulation of gene expression and male sterility is rapid divergence of male sex regulatory elements leading to incompatible interactions in an interspecies hybrid genome. To test the effect of regulatory divergence in spermatogenesis gene expression, we isolated 35 fertile D. simulans strains with D. mauritiana introgressions in either the X, second or third chromosome. We analyzed gene expression in these fertile hybrid strains for a subset of spermatogenesis genes previously reported as significantly under expressed in sterile hybrids relative to D. simulans. We found that fertile autosomal introgressions can cause levels of gene down regulation similar to that of sterile hybrids. We also found that X chromosome heterospecific introgressions cause significantly less gene down regulation than autosomal introgressions. Our results provide evidence that rapid male sex gene regulatory divergence can explain misexpression of spermatogenesis genes in hybrids.

  18. BRAZILIAN FEMINIST MOVEMENT: REPERTOIRE AND STRATEGIES FOR ACTION

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    Carla de Paiva Bezerra

    2014-08-01

    Full Text Available This article aims at analyzing the development of and changes in, the repertoire and strategies for action of the Brazilian feminist movement, in the period between the democratic “re-opening” set in the 1980s and the first decade of the XXI century. Our interest is centered in two foci of analysis: on the one hand, it focuses on the movement’s positioning in relation to the State, which varied from a situation of opposition, or even of indifference, to direct attempts at influencing public policies and actions in the State sphere, whether through party politics or participative institutions. On the other hand, we are interested in analyzing how, and in which specific moments, agency beyond the national feminist frontiers takes place and in which measure this influences the local repertoires and vice-versa.

  19. Somatic hypermutation of the new antigen receptor gene (NAR) in the nurse shark does not generate the repertoire: possible role in antigen-driven reactions in the absence of germinal centers.

    Science.gov (United States)

    Diaz, M; Greenberg, A S; Flajnik, M F

    1998-11-24

    The new antigen receptor (NAR) gene in the nurse shark diversifies extensively by somatic hypermutation. It is not known, however, whether NAR somatic hypermutation generates the primary repertoire (like in the sheep) or rather is used in antigen-driven immune responses. To address this issue, the sequences of NAR transmembrane (Tm) and secretory (Sec) forms, presumed to represent the primary and secondary repertoires, respectively, were examined from the peripheral blood lymphocytes of three adult nurse sharks. More than 40% of the Sec clones but fewer than 11% of Tm clones contained five mutations or more. Furthermore, more than 75% of the Tm clones had few or no mutations. Mutations in the Sec clones occurred mostly in the complementarity-determining regions (CDR) with a significant bias toward replacement substitutions in CDR1; in Tm clones there was no significant bias toward replacements and only a low level of targeting to the CDRs. Unlike the Tm clones where the replacement mutational pattern was similar to that seen for synonymous changes, Sec replacements displayed a distinct pattern of mutations. The types of mutations in NAR were similar to those found in mouse Ig genes rather than to the unusual pattern reported for shark and Xenopus Ig. Finally, an oligoclonal family of Sec clones revealed a striking trend toward acquisition of glutamic/aspartic acid, suggesting some degree of selection. These data strongly suggest that hypermutation of NAR does not generate the repertoire, but instead is involved in antigen-driven immune responses.

  20. Production of recombinant Ig molecules from antigen-selected single B cells and restricted usage of Ig-gene segments by anti-D antibodies

    NARCIS (Netherlands)

    Dohmen, Serge E.; Mulder, Arend; Verhagen, Onno J. H. M.; Eijsink, Chantal; Franke-van Dijk, Marry E. I.; van der Schoot, C. Ellen

    2005-01-01

    The Ig-genes of the heavy chains in anti-D-specific hybridomas and Fab/scFv-fragments selected from phage-display libraries are restricted to a group of closely related genes (IGHV3s genes). We analyzed the Ig-gene repertoire in anti-D-specific B cells of two hyperimmunized donors using a completely

  1. The molecular evolution of cytochrome P450 genes within and between drosophila species.

    Science.gov (United States)

    Good, Robert T; Gramzow, Lydia; Battlay, Paul; Sztal, Tamar; Batterham, Philip; Robin, Charles

    2014-04-20

    We map 114 gene gains and 74 gene losses in the P450 gene family across the phylogeny of 12 Drosophila species by examining the congruence of gene trees and species trees. Although the number of P450 genes varies from 74 to 94 in the species examined, we infer that there were at least 77 P450 genes in the ancestral Drosophila genome. One of the most striking observations in the data set is the elevated loss of P450 genes in the Drosophila sechellia lineage. The gain and loss events are not evenly distributed among the P450 genes-with 30 genes showing no gene gains or losses whereas others show as many as 20 copy number changes among the species examined. The P450 gene clades showing the fewest number of gene gain and loss events tend to be those evolving with the most purifying selection acting on the protein sequences, although there are exceptions, such as the rapid rate of amino acid replacement observed in the single copy phantom (Cyp306a1) gene. Within D. melanogaster, we observe gene copy number polymorphism in ten P450 genes including multiple cases of interparalog chimeras. Nonallelic homologous recombination (NAHR) has been associated with deleterious mutations in humans, but here we provide a second possible example of an NAHR event in insect P450s being adaptive. Specifically, we find that a polymorphic Cyp12a4/Cyp12a5 chimera correlates with resistance to an insecticide. Although we observe such interparalog exchange in our within-species data sets, we have little evidence of it between species, raising the possibility that such events may occur more frequently than appreciated but are masked by subsequent sequence change. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  2. Identification of hare meat by a species-specific marker of mitochondrial origin.

    Science.gov (United States)

    Santos, Cristina G; Melo, Vitor S; Amaral, Joana S; Estevinho, Letícia; Oliveira, M Beatriz P P; Mafra, Isabel

    2012-03-01

    Meat species identification in food has gained increasing interest in recent years due to public health, economic and legal concerns. Following the consumer trend towards high quality products, game meat has earned much attention. The aim of the present work was to develop a DNA-based technique able to identify hare meat. Mitochondrial cytochrome b gene was used to design species-specific primers for hare detection. The new primers proved to be highly specific to Lepus species, allowing the detection of 0.01% of hare meat in pork meat by polymerase chain reaction (PCR). A real-time PCR assay with the new intercalating EvaGreen dye was further proposed as a specific and fast tool for hare identification with increased sensitivity (1pg) compared to end-point PCR (10pg). It can be concluded that the proposed new primers can be used by both species-specific end-point PCR or real-time PCR to accurately authenticate hare meat. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Reconciliation of Gene and Species Trees

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    L. Y. Rusin

    2014-01-01

    Full Text Available The first part of the paper briefly overviews the problem of gene and species trees reconciliation with the focus on defining and algorithmic construction of the evolutionary scenario. Basic ideas are discussed for the aspects of mapping definitions, costs of the mapping and evolutionary scenario, imposing time scales on a scenario, incorporating horizontal gene transfers, binarization and reconciliation of polytomous trees, and construction of species trees and scenarios. The review does not intend to cover the vast diversity of literature published on these subjects. Instead, the authors strived to overview the problem of the evolutionary scenario as a central concept in many areas of evolutionary research. The second part provides detailed mathematical proofs for the solutions of two problems: (i inferring a gene evolution along a species tree accounting for various types of evolutionary events and (ii trees reconciliation into a single species tree when only gene duplications and losses are allowed. All proposed algorithms have a cubic time complexity and are mathematically proved to find exact solutions. Solving algorithms for problem (ii can be naturally extended to incorporate horizontal transfers, other evolutionary events, and time scales on the species tree.

  4. Distribution and development of the postnatal murine V delta 1 T-cell receptor repertoire

    Czech Academy of Sciences Publication Activity Database

    Holtmeier, W.; Gille, J.; Zeuzem, S.; Šinkora, Marek

    2010-01-01

    Roč. 131, č. 2 (2010), s. 192-201 ISSN 0019-2805 R&D Projects: GA ČR GA524/07/0087 Institutional research plan: CEZ:AV0Z50200510 Keywords : gene rearrangement * repertoire development * rodent Subject RIV: EE - Microbiology, Virology Impact factor: 3.302, year: 2010

  5. METHODOLOGICAL PRINCIPLES OF FORMING REPERTOIRE OF STUDENTS’ FOLK INSTRUMENTAL ORCHESTRA

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    Mykola Pshenychnykh

    2016-11-01

    Full Text Available One of the main aspects of forming future music teachers’ professional competence, connected with mastering professional musical and performing skills in the course “Orchestra Class” and realized in the activity of students’ performing group, is revealed. Nowadays the problem of creative personality development is relevant, as creative future music art teachers freely orient themselves and guide pupils students in today's cultural environment, music and media space, have a strong musical taste and aesthetic guidelines. The music genre groups have been characterized in the article. It is thought that these groups are the traditional components of repertoire of folk and orchestra student groups: arrangements of folk tunes; works of Ukrainian and world classics, orchestrated for the folk groups, taking into account each orchestra performing possibilities; works by contemporary authors, written specifically for the orchestra of folk instruments. The main methodological principles of selecting the repertoire for the student orchestra of folk instruments are disclosed, including: technical, artistic and performing capabilities of student groups; involvement of works of different genres into the repertoire; correspondence of orchestra scores to instrumental composition of the student orchestra, and their correction if it is necessary; selecting works, whose performing arouses interest of the student audience; using the experience of the leading professional ensembles of folk instruments; constant updating the orchestra's repertoire. In the conclusion the author emphasizes that taking into account the methodological tips helps solve the main tasks within the course of “Orchestra Class”. These tips are the following: students’ acquaintance with the history of foundation, composition, ways of musicianship, technique of playing the instrument of folk instrument orchestra and acquaintance with specific orchestral music; development of all

  6. Identification of Candida Species Using MP65 Gene and Evaluation of the Candida albicans MP65 Gene Expression in BALB/C Mice.

    Science.gov (United States)

    Bineshian, Farahnaz; Yadegari, Mohammad Hossien; Sharifi, Zohre; Akbari Eidgahi, Mohammadreza; Nasr, Reza

    2015-05-01

    Systemic candidiasis is a major public health concern. In particular, in immunocompromised people, such as patients with neutropenia, patients with Acquired Immune Deficiency Syndrome (AIDS) and cancer who are undergoing antiballistic chemotherapy or bone marrow transplants, and people with diabetes. Since the clinical signs and symptoms are nonspecific, early diagnosis is often difficult. The 65-kDa mannoprotein (MP65) gene of Candida albicans is appropriate for detection and identification of systemic candidiasis. This gene encodes a putative b-glucanase mannoprotein of 65 kDa, which plays a major role in the host-fungus relationship, morphogenesis and pathogenicity. The current study aimed to identify different species of Candida (C. albicans, C. glabrata and C. parapsilosis) using the Polymerase Chain Reaction (PCR) technique and also to evaluate C. albicans MP65 gene expression in BALB/C mice. All yeast isolates were identified on cornmeal agar supplemented with tween-80, germ tube formation in serum, and assimilation of carbon sources in the API 20 C AUX yeast identification system. Polymerase Chain Reaction was performed on all samples using species-specific primers for the MP65 65 kDa gene. After RNA extraction, cDNA synthesis was performed by the Maxime RT Pre Mix kit. Candida albicans MP65 gene expression was evaluated by quantitative Real-Time (q Real-Time) and Real-Time (RT) PCR techniques. The 2-ΔΔCT method was used to analyze relative changes in gene expression of MP65. For statistical analysis, nonparametric Wilcoxon test was applied using the SPSS version 16 software. Using biochemical methods, one hundred, six and one isolates of clinical samples were determined as C. albicans, C. glabrata and C. parapsilosis, respectively. Species-specific primers for PCR experiments were applied to clinical specimens, and in all cases a single expected band for C. albicans, C. glabrata and C. parapsilosis was obtained (475, 361 and 124 base pairs, respectively

  7. Specific versus non-specific immune responses in an invertebrate species evidenced by a comparative de novo sequencing study.

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    Emeline Deleury

    Full Text Available Our present understanding of the functioning and evolutionary history of invertebrate innate immunity derives mostly from studies on a few model species belonging to ecdysozoa. In particular, the characterization of signaling pathways dedicated to specific responses towards fungi and Gram-positive or Gram-negative bacteria in Drosophila melanogaster challenged our original view of a non-specific immunity in invertebrates. However, much remains to be elucidated from lophotrochozoan species. To investigate the global specificity of the immune response in the fresh-water snail Biomphalaria glabrata, we used massive Illumina sequencing of 5'-end cDNAs to compare expression profiles after challenge by Gram-positive or Gram-negative bacteria or after a yeast challenge. 5'-end cDNA sequencing of the libraries yielded over 12 millions high quality reads. To link these short reads to expressed genes, we prepared a reference transcriptomic database through automatic assembly and annotation of the 758,510 redundant sequences (ESTs, mRNAs of B. glabrata available in public databases. Computational analysis of Illumina reads followed by multivariate analyses allowed identification of 1685 candidate transcripts differentially expressed after an immune challenge, with a two fold ratio between transcripts showing a challenge-specific expression versus a lower or non-specific differential expression. Differential expression has been validated using quantitative PCR for a subset of randomly selected candidates. Predicted functions of annotated candidates (approx. 700 unisequences belonged to a large extend to similar functional categories or protein types. This work significantly expands upon previous gene discovery and expression studies on B. glabrata and suggests that responses to various pathogens may involve similar immune processes or signaling pathways but different genes belonging to multigenic families. These results raise the question of the importance

  8. Cross-species transcriptomic approach reveals genes in hamster implantation sites.

    Science.gov (United States)

    Lei, Wei; Herington, Jennifer; Galindo, Cristi L; Ding, Tianbing; Brown, Naoko; Reese, Jeff; Paria, Bibhash C

    2014-12-01

    The mouse model has greatly contributed to understanding molecular mechanisms involved in the regulation of progesterone (P4) plus estrogen (E)-dependent blastocyst implantation process. However, little is known about contributory molecular mechanisms of the P4-only-dependent blastocyst implantation process that occurs in species such as hamsters, guineapigs, rabbits, pigs, rhesus monkeys, and perhaps humans. We used the hamster as a model of P4-only-dependent blastocyst implantation and carried out cross-species microarray (CSM) analyses to reveal differentially expressed genes at the blastocyst implantation site (BIS), in order to advance the understanding of molecular mechanisms of implantation. Upregulation of 112 genes and downregulation of 77 genes at the BIS were identified using a mouse microarray platform, while use of the human microarray revealed 62 up- and 38 down-regulated genes at the BIS. Excitingly, a sizable number of genes (30 up- and 11 down-regulated genes) were identified as a shared pool by both CSMs. Real-time RT-PCR and in situ hybridization validated the expression patterns of several up- and down-regulated genes identified by both CSMs at the hamster and mouse BIS to demonstrate the merit of CSM findings across species, in addition to revealing genes specific to hamsters. Functional annotation analysis found that genes involved in the spliceosome, proteasome, and ubiquination pathways are enriched at the hamster BIS, while genes associated with tight junction, SAPK/JNK signaling, and PPARα/RXRα signalings are repressed at the BIS. Overall, this study provides a pool of genes and evidence of their participation in up- and down-regulated cellular functions/pathways at the hamster BIS. © 2014 Society for Reproduction and Fertility.

  9. The other side of comparative genomics: genes with no orthologs between the cow and other mammalian species

    Directory of Open Access Journals (Sweden)

    Ajmone-Marsan Paolo

    2009-12-01

    Full Text Available Abstract Background With the rapid growth in the availability of genome sequence data, the automated identification of orthologous genes between species (orthologs is of fundamental importance to facilitate functional annotation and studies on comparative and evolutionary genomics. Genes with no apparent orthologs between the bovine and human genome may be responsible for major differences between the species, however, such genes are often neglected in functional genomics studies. Results A BLAST-based method was exploited to explore the current annotation and orthology predictions in Ensembl. Genes with no orthologs between the two genomes were classified into groups based on alignments, ontology, manual curation and publicly available information. Starting from a high quality and specific set of orthology predictions, as provided by Ensembl, hidden relationship between genes and genomes of different mammalian species were unveiled using a highly sensitive approach, based on sequence similarity and genomic comparison. Conclusions The analysis identified 3,801 bovine genes with no orthologs in human and 1010 human genes with no orthologs in cow, among which 411 and 43 genes, respectively, had no match at all in the other species. Most of the apparently non-orthologous genes may potentially have orthologs which were missed in the annotation process, despite having a high percentage of identity, because of differences in gene length and structure. The comparative analysis reported here identified gene variants, new genes and species-specific features and gave an overview of the other side of orthology which may help to improve the annotation of the bovine genome and the knowledge of structural differences between species.

  10. Sex linkage, sex-specific selection, and the role of recombination in the evolution of sexually dimorphic gene expression.

    Science.gov (United States)

    Connallon, Tim; Clark, Andrew G

    2010-12-01

    Sex-biased genes--genes that are differentially expressed within males and females--are nonrandomly distributed across animal genomes, with sex chromosomes and autosomes often carrying markedly different concentrations of male- and female-biased genes. These linkage patterns are often gene- and lineage-dependent, differing between functional genetic categories and between species. Although sex-specific selection is often hypothesized to shape the evolution of sex-linked and autosomal gene content, population genetics theory has yet to account for many of the gene- and lineage-specific idiosyncrasies emerging from the empirical literature. With the goal of improving the connection between evolutionary theory and a rapidly growing body of genome-wide empirical studies, we extend previous population genetics theory of sex-specific selection by developing and analyzing a biologically informed model that incorporates sex linkage, pleiotropy, recombination, and epistasis, factors that are likely to vary between genes and between species. Our results demonstrate that sex-specific selection and sex-specific recombination rates can generate, and are compatible with, the gene- and species-specific linkage patterns reported in the genomics literature. The theory suggests that sexual selection may strongly influence the architectures of animal genomes, as well as the chromosomal distribution of fixed substitutions underlying sexually dimorphic traits. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

  11. Compendium of Immune Signatures Identifies Conserved and Species-Specific Biology in Response to Inflammation.

    Science.gov (United States)

    Godec, Jernej; Tan, Yan; Liberzon, Arthur; Tamayo, Pablo; Bhattacharya, Sanchita; Butte, Atul J; Mesirov, Jill P; Haining, W Nicholas

    2016-01-19

    Gene-expression profiling has become a mainstay in immunology, but subtle changes in gene networks related to biological processes are hard to discern when comparing various datasets. For instance, conservation of the transcriptional response to sepsis in mouse models and human disease remains controversial. To improve transcriptional analysis in immunology, we created ImmuneSigDB: a manually annotated compendium of ∼5,000 gene-sets from diverse cell states, experimental manipulations, and genetic perturbations in immunology. Analysis using ImmuneSigDB identified signatures induced in activated myeloid cells and differentiating lymphocytes that were highly conserved between humans and mice. Sepsis triggered conserved patterns of gene expression in humans and mouse models. However, we also identified species-specific biological processes in the sepsis transcriptional response: although both species upregulated phagocytosis-related genes, a mitosis signature was specific to humans. ImmuneSigDB enables granular analysis of transcriptomic data to improve biological understanding of immune processes of the human and mouse immune systems. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Strain diversity and host specificity in a specialized gut symbiont of honeybees and bumblebees.

    Science.gov (United States)

    Powell, Elijah; Ratnayeke, Nalin; Moran, Nancy A

    2016-09-01

    Host-restricted lineages of gut bacteria often include many closely related strains, but this fine-scale diversity is rarely investigated. The specialized gut symbiont Snodgrassella alvi has codiversified with honeybees (Apis mellifera) and bumblebees (Bombus) for millions of years. Snodgrassella alvi strains are nearly identical for 16S rRNA gene sequences but have distinct gene repertoires potentially affecting host biology and community interactions. We examined S. alvi strain diversity within and between hosts using deep sequencing both of a single-copy coding gene (minD) and of the V4 region of the 16S rRNA gene. We sampled workers from domestic and feral A. mellifera colonies and wild-caught Bombus representing 14 species. Conventional analyses of community profiles, based on the V4 region of the 16S rRNA gene, failed to expose most strain variation. In contrast, the minD analysis revealed extensive strain variation within and between host species and individuals. Snodgrassella alvi strain diversity is significantly higher in A. mellifera than in Bombus, supporting the hypothesis that colony founding by swarms of workers enables retention of more diversity than colony founding by a single queen. Most Bombus individuals (72%) are dominated by a single S. alvi strain, whereas most A. mellifera (86%) possess multiple strains. No S. alvi strains are shared between A. mellifera and Bombus, indicating some host specificity. Among Bombus-restricted strains, some are restricted to a single host species or subgenus, while others occur in multiple subgenera. Findings demonstrate that strains diversify both within and between host species and can be highly specific or relatively generalized in their host associations. © 2016 John Wiley & Sons Ltd.

  13. The natural antibody repertoire of sharks and humans recognizes the potential universe of antigens.

    Science.gov (United States)

    Adelman, Miranda K; Schluter, Samuel F; Marchalonis, John J

    2004-02-01

    In ancestral sharks, a rapid emergence in the evolution of the immune system occurred, giving jawed-vertebrates the necessary components for the combinatorial immune response (CIR). To compare the natural antibody (NAb) repertoires of the most divergent vertebrates with the capacity to produce antibodies, we isolated NAbs to the same set of antigens by affinity chromatography from two species of Carcharhine sharks and from human polyclonal IgG and IgM antibody preparations. The activities of the affinity-purified anti-T-cell receptor (anti-TCR) NAbs were compared with those of monoclonal anti-TCR NAbs that were generated from a systemic lupus erythematosus patient. We report that sharks and humans, representing the evolutionary extremes of vertebrate species sharing the CIR, have NAbs to human TCRs, Igs, the human senescent cell antigen, and to numerous retroviral antigens, indicating that essential features of the combinatorial repertoire and the capacity to recognize the potential universe of antigens is shared among all jawed-vertebrates.

  14. Identification of Carbohydrate Metabolism Genes in the Metagenome of a Marine Biofilm Community Shown to Be Dominated by Gammaproteobacteria and Bacteroidetes

    Directory of Open Access Journals (Sweden)

    Jennifer L. Edwards

    2010-10-01

    Full Text Available Polysaccharides are an important source of organic carbon in the marine environment and degradation of the insoluble and globally abundant cellulose is a major component of the marine carbon cycle. Although a number of species of cultured bacteria are known to degrade crystalline cellulose, little is known of the polysaccharide hydrolases expressed by cellulose-degrading microbial communities, particularly in the marine environment. Next generation 454 Pyrosequencing was applied to analyze the microbial community that colonizes and degrades insoluble polysaccharides in situ in the Irish Sea. The bioinformatics tool MG-RAST was used to examine the randomly sampled data for taxonomic markers and functional genes, and showed that the community was dominated by members of the Gammaproteobacteria and Bacteroidetes. Furthermore, the identification of 211 gene sequences matched to a custom-made database comprising the members of nine glycoside hydrolase families revealed an extensive repertoire of functional genes predicted to be involved in cellulose utilization. This demonstrates that the use of an in situ cellulose baiting method yielded a marine microbial metagenome considerably enriched in functional genes involved in polysaccharide degradation. The research reported here is the first designed to specifically address the bacterial communities that colonize and degrade cellulose in the marine environment and to evaluate the glycoside hydrolase (cellulase and chitinase gene repertoire of that community, in the absence of the biases associated with PCR-based molecular techniques.

  15. The vocal repertoire of the African Penguin (Spheniscus demersus): structure and function of calls.

    Science.gov (United States)

    Favaro, Livio; Ozella, Laura; Pessani, Daniela

    2014-01-01

    The African Penguin (Spheniscus demersus) is a highly social and vocal seabird. However, currently available descriptions of the vocal repertoire of African Penguin are mostly limited to basic descriptions of calls. Here we provide, for the first time, a detailed description of the vocal behaviour of this species by collecting audio and video recordings from a large captive colony. We combine visual examinations of spectrograms with spectral and temporal acoustic analyses to determine vocal categories. Moreover, we used a principal component analysis, followed by signal classification with a discriminant function analysis, for statistical validation of the vocalisation types. In addition, we identified the behavioural contexts in which calls were uttered. The results show that four basic vocalisations can be found in the vocal repertoire of adult African Penguin, namely a contact call emitted by isolated birds, an agonistic call used in aggressive interactions, an ecstatic display song uttered by single birds, and a mutual display song vocalised by pairs, at their nests. Moreover, we identified two distinct vocalisations interpreted as begging calls by nesting chicks (begging peep) and unweaned juveniles (begging moan). Finally, we discussed the importance of specific acoustic parameters in classifying calls and the possible use of the source-filter theory of vocal production to study penguin vocalisations.

  16. Mining whole genomes and transcriptomes of Jatropha (Jatropha curcas) and Castor bean (Ricinus communis) for NBS-LRR genes and defense response associated transcription factors.

    Science.gov (United States)

    Sood, Archit; Jaiswal, Varun; Chanumolu, Sree Krishna; Malhotra, Nikhil; Pal, Tarun; Chauhan, Rajinder Singh

    2014-11-01

    Jatropha (Jatropha curcas L.) and Castor bean (Ricinus communis) are oilseed crops of family Euphorbiaceae with the potential of producing high quality biodiesel and having industrial value. Both the bioenergy plants are becoming susceptible to various biotic stresses directly affecting the oil quality and content. No report exists as of today on analysis of Nucleotide Binding Site-Leucine Rich Repeat (NBS-LRR) gene repertoire and defense response transcription factors in both the plant species. In silico analysis of whole genomes and transcriptomes identified 47 new NBS-LRR genes in both the species and 122 and 318 defense response related transcription factors in Jatropha and Castor bean, respectively. The identified NBS-LRR genes and defense response transcription factors were mapped onto the respective genomes. Common and unique NBS-LRR genes and defense related transcription factors were identified in both the plant species. All NBS-LRR genes in both the species were characterized into Toll/interleukin-1 receptor NBS-LRRs (TNLs) and coiled-coil NBS-LRRs (CNLs), position on contigs, gene clusters and motifs and domains distribution. Transcript abundance or expression values were measured for all NBS-LRR genes and defense response transcription factors, suggesting their functional role. The current study provides a repertoire of NBS-LRR genes and transcription factors which can be used in not only dissecting the molecular basis of disease resistance phenotype but also in developing disease resistant genotypes in Jatropha and Castor bean through transgenic or molecular breeding approaches.

  17. High-throughput Sequencing Based Immune Repertoire Study during Infectious Disease

    Directory of Open Access Journals (Sweden)

    Dongni Hou

    2016-08-01

    Full Text Available The selectivity of the adaptive immune response is based on the enormous diversity of T and B cell antigen-specific receptors. The immune repertoire, the collection of T and B cells with functional diversity in the circulatory system at any given time, is dynamic and reflects the essence of immune selectivity. In this article, we review the recent advances in immune repertoire study of infectious diseases that achieved by traditional techniques and high-throughput sequencing techniques. High-throughput sequencing techniques enable the determination of complementary regions of lymphocyte receptors with unprecedented efficiency and scale. This progress in methodology enhances the understanding of immunologic changes during pathogen challenge, and also provides a basis for further development of novel diagnostic markers, immunotherapies and vaccines.

  18. Rapid evolution of female-biased genes among four species of Anopheles malaria mosquitoes.

    Science.gov (United States)

    Papa, Francesco; Windbichler, Nikolai; Waterhouse, Robert M; Cagnetti, Alessia; D'Amato, Rocco; Persampieri, Tania; Lawniczak, Mara K N; Nolan, Tony; Papathanos, Philippos Aris

    2017-09-01

    Understanding how phenotypic differences between males and females arise from the sex-biased expression of nearly identical genomes can reveal important insights into the biology and evolution of a species. Among Anopheles mosquito species, these phenotypic differences include vectorial capacity, as it is only females that blood feed and thus transmit human malaria. Here, we use RNA-seq data from multiple tissues of four vector species spanning the Anopheles phylogeny to explore the genomic and evolutionary properties of sex-biased genes. We find that, in these mosquitoes, in contrast to what has been found in many other organisms, female-biased genes are more rapidly evolving in sequence, expression, and genic turnover than male-biased genes. Our results suggest that this atypical pattern may be due to the combination of sex-specific life history challenges encountered by females, such as blood feeding. Furthermore, female propensity to mate only once in nature in male swarms likely diminishes sexual selection of post-reproductive traits related to sperm competition among males. We also develop a comparative framework to systematically explore tissue- and sex-specific splicing to document its conservation throughout the genus and identify a set of candidate genes for future functional analyses of sex-specific isoform usage. Finally, our data reveal that the deficit of male-biased genes on the X Chromosomes in Anopheles is a conserved feature in this genus and can be directly attributed to chromosome-wide transcriptional regulation that de-masculinizes the X in male reproductive tissues. © 2017 Papa et al.; Published by Cold Spring Harbor Laboratory Press.

  19. Generation of Novel Traj18-Deficient Mice Lacking Vα14 Natural Killer T Cells with an Undisturbed T Cell Receptor α-Chain Repertoire.

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    Nyambayar Dashtsoodol

    Full Text Available Invariant Vα14 natural killer T (NKT cells, characterized by the expression of a single invariant T cell receptor (TCR α chain encoded by rearranged Trav11 (Vα14-Traj18 (Jα18 gene segments in mice, and TRAV10 (Vα24-TRAJ18 (Jα18 in humans, mediate adjuvant effects to activate various effector cell types in both innate and adaptive immune systems that facilitates the potent antitumor effects. It was recently reported that the Jα18-deficient mouse described by our group in 1997 harbors perturbed TCRα repertoire, which raised concerns regarding the validity of some of the experimental conclusions that have been made using this mouse line. To resolve this concern, we generated a novel Traj18-deficient mouse line by specifically targeting the Traj18 gene segment using Cre-Lox approach. Here we showed the newly generated Traj18-deficient mouse has, apart from the absence of Traj18, an undisturbed TCRα chain repertoire by using next generation sequencing and by detecting normal generation of Vα19Jα33 expressing mucosal associated invariant T cells, whose development was abrogated in the originally described Jα18-KO mice. We also demonstrated here the definitive requirement for NKT cells in the protection against tumors and their potent adjuvant effects on antigen-specific CD8 T cells.

  20. Genome-wide comparative analysis of NBS-encoding genes between Brassica species and Arabidopsis thaliana.

    Science.gov (United States)

    Yu, Jingyin; Tehrim, Sadia; Zhang, Fengqi; Tong, Chaobo; Huang, Junyan; Cheng, Xiaohui; Dong, Caihua; Zhou, Yanqiu; Qin, Rui; Hua, Wei; Liu, Shengyi

    2014-01-03

    Plant disease resistance (R) genes with the nucleotide binding site (NBS) play an important role in offering resistance to pathogens. The availability of complete genome sequences of Brassica oleracea and Brassica rapa provides an important opportunity for researchers to identify and characterize NBS-encoding R genes in Brassica species and to compare with analogues in Arabidopsis thaliana based on a comparative genomics approach. However, little is known about the evolutionary fate of NBS-encoding genes in the Brassica lineage after split from A. thaliana. Here we present genome-wide analysis of NBS-encoding genes in B. oleracea, B. rapa and A. thaliana. Through the employment of HMM search and manual curation, we identified 157, 206 and 167 NBS-encoding genes in B. oleracea, B. rapa and A. thaliana genomes, respectively. Phylogenetic analysis among 3 species classified NBS-encoding genes into 6 subgroups. Tandem duplication and whole genome triplication (WGT) analyses revealed that after WGT of the Brassica ancestor, NBS-encoding homologous gene pairs on triplicated regions in Brassica ancestor were deleted or lost quickly, but NBS-encoding genes in Brassica species experienced species-specific gene amplification by tandem duplication after divergence of B. rapa and B. oleracea. Expression profiling of NBS-encoding orthologous gene pairs indicated the differential expression pattern of retained orthologous gene copies in B. oleracea and B. rapa. Furthermore, evolutionary analysis of CNL type NBS-encoding orthologous gene pairs among 3 species suggested that orthologous genes in B. rapa species have undergone stronger negative selection than those in B .oleracea species. But for TNL type, there are no significant differences in the orthologous gene pairs between the two species. This study is first identification and characterization of NBS-encoding genes in B. rapa and B. oleracea based on whole genome sequences. Through tandem duplication and whole genome

  1. Phenotypic integration and the evolution of signal repertoires: A case study of treefrog acoustic communication.

    Science.gov (United States)

    Reichert, Michael S; Höbel, Gerlinde

    2018-03-01

    Animal signals are inherently complex phenotypes with many interacting parts combining to elicit responses from receivers. The pattern of interrelationships between signal components reflects the extent to which each component is expressed, and responds to selection, either in concert with or independently of others. Furthermore, many species have complex repertoires consisting of multiple signal types used in different contexts, and common morphological and physiological constraints may result in interrelationships extending across the multiple signals in species' repertoires. The evolutionary significance of interrelationships between signal traits can be explored within the framework of phenotypic integration, which offers a suite of quantitative techniques to characterize complex phenotypes. In particular, these techniques allow for the assessment of modularity and integration, which describe, respectively, the extent to which sets of traits covary either independently or jointly. Although signal and repertoire complexity are thought to be major drivers of diversification and social evolution, few studies have explicitly measured the phenotypic integration of signals to investigate the evolution of diverse communication systems. We applied methods from phenotypic integration studies to quantify integration in the two primary vocalization types (advertisement and aggressive calls) in the treefrogs Hyla versicolor , Hyla cinerea, and Dendropsophus ebraccatus . We recorded male calls and calculated standardized phenotypic variance-covariance ( P ) matrices for characteristics within and across call types. We found significant integration across call types, but the strength of integration varied by species and corresponded with the acoustic similarity of the call types within each species. H. versicolor had the most modular advertisement and aggressive calls and the least acoustically similar call types. Additionally, P was robust to changing social competition

  2. Complex expression patterns of lymphocyte-specific genes during the development of cartilaginous fish implicate unique lymphoid tissues in generating an immune repertoire

    Science.gov (United States)

    Miracle, A. L.; Anderson, M. K.; Litman, R. T.; Walsh, C. J.; Luer, C. A.; Rothenberg, E. V.; Litman, G. W.

    2001-01-01

    Cartilaginous fish express canonical B and T cell recognition genes, but their lymphoid organs and lymphocyte development have been poorly defined. Here, the expression of Ig, TCR, recombination-activating gene (Rag)-1 and terminal deoxynucleosidase (TdT) genes has been used to identify roles of various lymphoid tissues throughout development in the cartilaginous fish, Raja eglanteria (clearnose skate). In embryogenesis, Ig and TCR genes are sharply up-regulated at 8 weeks of development. At this stage TCR and TdT expression is limited to the thymus; later, TCR gene expression appears in peripheral sites in hatchlings and adults, suggesting that the thymus is a source of T cells as in mammals. B cell gene expression indicates more complex roles for the spleen and two special organs of cartilaginous fish-the Leydig and epigonal (gonad-associated) organs. In the adult, the Leydig organ is the site of the highest IgM and IgX expression. However, the spleen is the first site of IgM expression, while IgX is expressed first in gonad, liver, Leydig and even thymus. Distinctive spatiotemporal patterns of Ig light chain gene expression also are seen. A subset of Ig genes is pre-rearranged in the germline of the cartilaginous fish, making expression possible without rearrangement. To assess whether this allows differential developmental regulation, IgM and IgX heavy chain cDNA sequences from specific tissues and developmental stages have been compared with known germline-joined genomic sequences. Both non-productively rearranged genes and germline-joined genes are transcribed in the embryo and hatchling, but not in the adult.

  3. Cross-species mapping of bidirectional promoters enables prediction of unannotated 5' UTRs and identification of species-specific transcripts

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    Lewin Harris A

    2009-04-01

    Full Text Available Abstract Background Bidirectional promoters are shared regulatory regions that influence the expression of two oppositely oriented genes. This type of regulatory architecture is found more frequently than expected by chance in the human genome, yet many specifics underlying the regulatory design are unknown. Given that the function of most orthologous genes is similar across species, we hypothesized that the architecture and regulation of bidirectional promoters might also be similar across species, representing a core regulatory structure and enabling annotation of these regions in additional mammalian genomes. Results By mapping the intergenic distances of genes in human, chimpanzee, bovine, murine, and rat, we show an enrichment for pairs of genes equal to or less than 1,000 bp between their adjacent 5' ends ("head-to-head" compared to pairs of genes that fall in the same orientation ("head-to-tail" or whose 3' ends are side-by-side ("tail-to-tail". A representative set of 1,369 human bidirectional promoters was mapped to orthologous sequences in other mammals. We confirmed predictions for 5' UTRs in nine of ten manual picks in bovine based on comparison to the orthologous human promoter set and in six of seven predictions in human based on comparison to the bovine dataset. The two predictions that did not have orthology as bidirectional promoters in the other species resulted from unique events that initiated transcription in the opposite direction in only those species. We found evidence supporting the independent emergence of bidirectional promoters from the family of five RecQ helicase genes, which gained their bidirectional promoters and partner genes independently rather than through a duplication process. Furthermore, by expanding our comparisons from pairwise to multispecies analyses we developed a map representing a core set of bidirectional promoters in mammals. Conclusion We show that the orthologous positions of bidirectional

  4. Impaired recovery of syllable repertoires after unilateral lesions of the HVC of male domesticated canaries.

    NARCIS (Netherlands)

    Halle, F; Gahr, M.; Kreutzer, M.

    2003-01-01

    Particular features of the song of adult male canaries such as a large syllable repertoire resulting in a great diversity of song phrases and special so-called 'complex' syllables enhance various features of female reproductive behaviour. These features are produced in a species or strain dependent

  5. Lineage-Specific Expansion of the Chalcone Synthase Gene Family in Rosids.

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    Kattina Zavala

    Full Text Available Rosids are a monophyletic group that includes approximately 70,000 species in 140 families, and they are found in a variety of habitats and life forms. Many important crops such as fruit trees and legumes are rosids. The evolutionary success of this group may have been influenced by their ability to produce flavonoids, secondary metabolites that are synthetized through a branch of the phenylpropanoid pathway where chalcone synthase is a key enzyme. In this work, we studied the evolution of the chalcone synthase gene family in 12 species belonging to the rosid clade. Our results show that the last common ancestor of the rosid clade possessed six chalcone synthase gene lineages that were differentially retained during the evolutionary history of the group. In fact, of the six gene lineages that were present in the last common ancestor, 7 species retained 2 of them, whereas the other 5 only retained one gene lineage. We also show that one of the gene lineages was disproportionately expanded in species that belonged to the order Fabales (soybean, barrel medic and Lotus japonicas. Based on the available literature, we suggest that this gene lineage possesses stress-related biological functions (e.g., response to UV light, pathogen defense. We propose that the observed expansion of this clade was a result of a selective pressure to increase the amount of enzymes involved in the production of phenylpropanoid pathway-derived secondary metabolites, which is consistent with the hypothesis that suggested that lineage-specific expansions fuel plant adaptation.

  6. Immune Antibody Libraries: Manipulating The Diverse Immune Repertoire for Antibody Discovery.

    Science.gov (United States)

    Lim, Theam Soon; Chan, Soo Khim

    2016-01-01

    Antibody phage display is highly dependent on the availability of antibody libraries. There are several forms of libraries depending mainly on the origin of the source materials. There are three major classes of libraries, mainly the naïve, immune and synthetic libraries. Immune antibody libraries are designed to isolate specific and high affinity antibodies against disease antigens. The pre-exposure of the host to an infection results in the production of a skewed population of antibodies against the particular infection. This characteristic takes advantage of the in vivo editing machinery to generate bias and specific immune repertoire. The skewed but diverse repertoire of immune libraries has been adapted successfully in the generation of antibodies against a wide range of diseases. We envisage immune antibody libraries to play a greater role in the discovery of antibodies for diseases in the near future. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Mother-Newborn Pairs in Malawi Have Similar Antibody Repertoires to Diverse Malaria Antigens.

    Science.gov (United States)

    Boudová, Sarah; Walldorf, Jenny A; Bailey, Jason A; Divala, Titus; Mungwira, Randy; Mawindo, Patricia; Pablo, Jozelyn; Jasinskas, Algis; Nakajima, Rie; Ouattara, Amed; Adams, Matthew; Felgner, Philip L; Plowe, Christopher V; Travassos, Mark A; Laufer, Miriam K

    2017-10-01

    Maternal antibodies may play a role in protecting newborns against malaria disease. Plasmodium falciparum parasite surface antigens are diverse, and protection from infection requires allele-specific immunity. Although malaria-specific antibodies have been shown to cross the placenta, the extent to which antibodies that respond to the full repertoire of diverse antigens are transferred from the mother to the infant has not been explored. Understanding the breadth of maternal antibody responses and to what extent these antibodies are transferred to the child can inform vaccine design and evaluation. We probed plasma from cord blood and serum from mothers at delivery using a customized protein microarray that included variants of malaria vaccine target antigens to assess the intensity and breadth of seroreactivity to three malaria vaccine candidate antigens in mother-newborn pairs in Malawi. Among the 33 paired specimens that were assessed, mothers and newborns had similar intensity and repertoire of seroreactivity. Maternal antibody levels against vaccine candidate antigens were the strongest predictors of infant antibody levels. Placental malaria did not significantly impair transplacental antibody transfer. However, mothers with placental malaria had significantly higher antibody levels against these blood-stage antigens than mothers without placental malaria. The repertoire and levels of infant antibodies against a wide range of malaria vaccine candidate antigen variants closely mirror maternal levels in breadth and magnitude regardless of evidence of placental malaria. Vaccinating mothers with an effective malaria vaccine during pregnancy may induce high and potentially protective antibody repertoires in newborns. Copyright © 2017 American Society for Microbiology.

  8. Human IgG repertoire of malaria antigen-immunized human immune system (HIS) mice.

    Science.gov (United States)

    Nogueira, Raquel Tayar; Sahi, Vincent; Huang, Jing; Tsuji, Moriya

    2017-08-01

    Humanized mouse models present an important tool for preclinical evaluation of new vaccines and therapeutics. Here we show the human variable repertoire of antibody sequences cloned from a previously described human immune system (HIS) mouse model that possesses functional human CD4+ T cells and B cells, namely HIS-CD4/B mice. We sequenced variable IgG genes from single memory B-cell and plasma-cell sorted from splenocytes or whole blood lymphocytes of HIS-CD4/B mice that were vaccinated with a human plasmodial antigen, a recombinant Plasmodium falciparum circumsporozoite protein (rPfCSP). We demonstrate that rPfCSP immunization triggers a diverse B-cell IgG repertoire composed of various human VH family genes and distinct V(D)J recombinations that constitute diverse CDR3 sequences similar to humans, although low hypermutated sequences were generated. These results demonstrate the substantial genetic diversity of responding human B cells of HIS-CD4/B mice and their capacity to mount human IgG class-switched antibody response upon vaccination. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  9. Construction of naïve camelids VHH repertoire in phage display-based library.

    Science.gov (United States)

    Sabir, Jamal S M; Atef, Ahmed; El-Domyati, Fotouh M; Edris, Sherif; Hajrah, Nahid; Alzohairy, Ahmed M; Bahieldin, Ahmed

    2014-04-01

    Camelids have unique antibodies, namely HCAbs (VHH) or commercially named Nanobodies(®) (Nb) that are composed only of a heavy-chain homodimer. As libraries based on immunized camelids are time-consuming, costly and likely redundant for certain antigens, we describe the construction of a naïve camelid VHHs library from blood serum of non-immunized camelids with affinity in the subnanomolar range and suitable for standard immune applications. This approach is rapid and recovers VHH repertoire with the advantages of being more diverse, non-specific and devoid of subpopulations of specific antibodies, which allows the identification of binders for any potential antigen (or pathogen). RNAs from a number of camelids from Saudi Arabia were isolated and cDNAs of the diverse vhh gene were amplified; the resulting amplicons were cloned in the phage display pSEX81 vector. The size of the library was found to be within the required range (10(7)) suitable for subsequent applications in disease diagnosis and treatment. Two hundred clones were randomly selected and the inserted gene library was either estimated for redundancy or sequenced and aligned to the reference camelid vhh gene (acc. No. ADE99145). Results indicated complete non-specificity of this small library in which no single event of redundancy was detected. These results indicate the efficacy of following this approach in order to yield a large and diverse enough gene library to secure the presence of the required version encoding the required antibodies for any target antigen. This work is a first step towards the construction of phage display-based biosensors useful in disease (e.g., TB or tuberculosis) diagnosis and treatment. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  10. B cell repertoires in HLA-sensitized kidney transplant candidates undergoing desensitization therapy.

    Science.gov (United States)

    Beausang, John F; Fan, H Christina; Sit, Rene; Hutchins, Maria U; Jirage, Kshama; Curtis, Rachael; Hutchins, Edward; Quake, Stephen R; Yabu, Julie M

    2017-01-13

    Kidney transplantation is the most effective treatment for end-stage renal disease. Sensitization refers to pre-existing antibodies against human leukocyte antigen (HLA) protein and remains a major barrier to successful transplantation. Despite implementation of desensitization strategies, many candidates fail to respond. Our objective was to determine whether measuring B cell repertoires could differentiate candidates that respond to desensitization therapy. We developed an assay based on high-throughput DNA sequencing of the variable domain of the heavy chain of immunoglobulin genes to measure changes in B cell repertoires in 19 highly HLA-sensitized kidney transplant candidates undergoing desensitization and 7 controls with low to moderate HLA sensitization levels. Responders to desensitization had a decrease of 5% points or greater in cumulated calculated panel reactive antibody (cPRA) levels, and non-responders had no decrease in cPRA. Dominant B cell clones were not observed in highly sensitized candidates, suggesting that the B cells responsible for sensitization are either not present in peripheral blood or present at comparable levels to other circulating B cells. Candidates that responded to desensitization therapy had pre-treatment repertoires composed of a larger fraction of class-switched (IgG and IgA) isotypes compared to non-responding candidates. After B cell depleting therapy, the proportion of switched isotypes increased and the mutation frequencies of the remaining non-switched isotypes (IgM and IgD) increased in both responders and non-responders, perhaps representing a shift in the repertoire towards memory B cells or plasmablasts. Conversely, after transplantation, non-switched isotypes with fewer mutations increased, suggesting a shift in the repertoire towards naïve B cells. Relative abundance of different B cell isotypes is strongly perturbed by desensitization therapy and transplantation, potentially reflecting changes in the relative

  11. MicroRNA repertoire for functional genome research in tilapia identified by deep sequencing.

    Science.gov (United States)

    Yan, Biao; Wang, Zhen-Hua; Zhu, Chang-Dong; Guo, Jin-Tao; Zhao, Jin-Liang

    2014-08-01

    The Nile tilapia (Oreochromis niloticus; Cichlidae) is an economically important species in aquaculture and occupies a prominent position in the aquaculture industry. MicroRNAs (miRNAs) are a class of noncoding RNAs that post-transcriptionally regulate gene expression involved in diverse biological and metabolic processes. To increase the repertoire of miRNAs characterized in tilapia, we used the Illumina/Solexa sequencing technology to sequence a small RNA library using pooled RNA sample isolated from the different developmental stages of tilapia. Bioinformatic analyses suggest that 197 conserved and 27 novel miRNAs are expressed in tilapia. Sequence alignments indicate that all tested miRNAs and miRNAs* are highly conserved across many species. In addition, we characterized the tissue expression patterns of five miRNAs using real-time quantitative PCR. We found that miR-1/206, miR-7/9, and miR-122 is abundantly expressed in muscle, brain, and liver, respectively, implying a potential role in the regulation of tissue differentiation or the maintenance of tissue identity. Overall, our results expand the number of tilapia miRNAs, and the discovery of miRNAs in tilapia genome contributes to a better understanding the role of miRNAs in regulating diverse biological processes.

  12. Longitudinal multiparameter single-cell analysis of macaques immunized with pneumococcal protein-conjugated or unconjugated polysaccharide vaccines reveals distinct antigen specific memory B cell repertoires.

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    Bin Jia

    Full Text Available The efficacy of protein-conjugated pneumococcal polysaccharide vaccines has been well characterized for children. The level of protection conferred by unconjugated polysaccharide vaccines remains less clear, particularly for elderly individuals who have had prior antigenic experience through immunization with unconjugated polysaccharide vaccines or natural exposure to Streptococcus pneumoniae.We compared the magnitude, diversity and genetic biases of antigen-specific memory B cells in two groups of adult cynomolgus macaques that were immunized with a 7-valent conjugated vaccine and boosted after five years with either a 13-valent pneumococcal polysaccharide conjugate vaccine (13vPnC or a 23-valent unconjugated pneumococcal polysaccharide vaccine (23vPS using microengraving (a single-cell analysis method and single-cell RT-PCR.Seven days after boosting, the mean frequency of antigen-specific memory B cells was significantly increased in macaques vaccinated with 13vPnC compared to those receiving 23vPS. The 13vPnC-vaccinated macaques also exhibited a more even distribution of antibody specificities to four polysaccharides in the vaccine (PS4, 6B, 14, 23F that were examined. However, single-cell analysis of the antibody variable region sequences from antigen-specific B cells elicited by unconjugated and conjugated vaccines indicated that both the germline gene segments forming the heavy chains and the average lengths of the Complementary Determining Region 3 (CDR3 were similar.Our results confirm that distinctive differences can manifest between antigen-specific memory B cell repertoires in nonhuman primates immunized with conjugated and unconjugated pneumococcal polysaccharide vaccines. The study also supports the notion that the conjugated vaccines have a favorable profile in terms of both the frequency and breadth of the anamnestic response among antigen-specific memory B cells.

  13. Species-specific identification from incomplete sampling: applying DNA barcodes to monitoring invasive solanum plants.

    Science.gov (United States)

    Zhang, Wei; Fan, Xiaohong; Zhu, Shuifang; Zhao, Hong; Fu, Lianzhong

    2013-01-01

    Comprehensive sampling is crucial to DNA barcoding, but it is rarely performed because materials are usually unavailable. In practice, only a few rather than all species of a genus are required to be identified. Thus identification of a given species using a limited sample is of great importance in current application of DNA barcodes. Here, we selected 70 individuals representing 48 species from each major lineage of Solanum, one of the most species-rich genera of seed plants, to explore whether DNA barcodes can provide reliable specific-species discrimination in the context of incomplete sampling. Chloroplast genes ndhF and trnS-trnG and the nuclear gene waxy, the commonly used markers in Solanum phylogeny, were selected as the supplementary barcodes. The tree-building and modified barcode gap methods were employed to assess species resolution. The results showed that four Solanum species of quarantine concern could be successfully identified through the two-step barcoding sampling strategy. In addition, discrepancies between nuclear and cpDNA barcodes in some samples demonstrated the ability to discriminate hybrid species, and highlights the necessity of using barcode regions with different modes of inheritance. We conclude that efficient phylogenetic markers are good candidates as the supplementary barcodes in a given taxonomic group. Critically, we hypothesized that a specific-species could be identified from a phylogenetic framework using incomplete sampling-through this, DNA barcoding will greatly benefit the current fields of its application.

  14. Reranking candidate gene models with cross-species comparison for improved gene prediction

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    Pereira Fernando CN

    2008-10-01

    Full Text Available Abstract Background Most gene finders score candidate gene models with state-based methods, typically HMMs, by combining local properties (coding potential, splice donor and acceptor patterns, etc. Competing models with similar state-based scores may be distinguishable with additional information. In particular, functional and comparative genomics datasets may help to select among competing models of comparable probability by exploiting features likely to be associated with the correct gene models, such as conserved exon/intron structure or protein sequence features. Results We have investigated the utility of a simple post-processing step for selecting among a set of alternative gene models, using global scoring rules to rerank competing models for more accurate prediction. For each gene locus, we first generate the K best candidate gene models using the gene finder Evigan, and then rerank these models using comparisons with putative orthologous genes from closely-related species. Candidate gene models with lower scores in the original gene finder may be selected if they exhibit strong similarity to probable orthologs in coding sequence, splice site location, or signal peptide occurrence. Experiments on Drosophila melanogaster demonstrate that reranking based on cross-species comparison outperforms the best gene models identified by Evigan alone, and also outperforms the comparative gene finders GeneWise and Augustus+. Conclusion Reranking gene models with cross-species comparison improves gene prediction accuracy. This straightforward method can be readily adapted to incorporate additional lines of evidence, as it requires only a ranked source of candidate gene models.

  15. Multivariate analysis using high definition flow cytometry reveals distinct T cell repertoires between the foetal-maternal interface and the peripheral blood

    Directory of Open Access Journals (Sweden)

    Michelle eNeller

    2014-02-01

    Full Text Available The human T-cell compartment is a complex system and while some information is known on repertoire composition and dynamics in the peripheral blood, little is known on repertoire composition at different anatomical sites. Here, we determine the T-cell receptor β-variable (TRBV repertoire at the decidua and compare it with the peripheral blood during normal pregnancy and preclampsia. We found total T-cell subset disparity of up to 58% between sites, including large signature TRBV expansions unique to the foetal-maternal interface. Defining the functional nature and specificity of compartment-specific T-cells will be necessary if we are to understand localised immunity, tolerance and pathogenesis.

  16. Systematic development of Phytophthora species-specific mitochondrial diagnostic markers for economically important members of the genus

    Science.gov (United States)

    The genus Phytophthora contains many invasive species to the USA that have the potential to cause significant damage to agriculture and native ecosystems. A genus and species-specific diagnostic assay was previously reported based on mitochondrial gene order differences that allowed for the systemat...

  17. Development of a Species-specific PCR Assay for Three Xanthomonas Species, Causing Bulb and Flower Diseases, Based on Their Genome Sequences

    Directory of Open Access Journals (Sweden)

    Chang-Gi Back

    2015-09-01

    Full Text Available In this study, we developed a species-specific PCR assay for rapid and accurate detection of three Xanthomonas species, X. axonopodis pv. poinsettiicola (XAP, X. hyacinthi (XH and X. campestris pv. zantedeschiae (XCZ, based on their draft genome sequences. XAP, XH and XCZ genomes consist of single chromosomes that contain 5,221, 4,395 and 7,986 protein coding genes, respectively. Species-specific primers were designed from variable regions of the draft genome sequence data and assessed by a PCR-based detection method. These primers were also tested for specificity against 17 allied Xanthomonas species as well as against the host DNA and the microbial community of the host surface. Three primer sets were found to be very specific and no amplification product was obtained with the host DNA and the microbial community of the host surface. In addition, a detection limit of 1 pg/μl per PCR reaction was detected when these primer sets were used to amplify corresponding bacterial DNAs. Therefore, these primer sets and the developed species-specific PCR assay represent a valuable, sensitive, and rapid diagnostic tool that can be used to detect three specific pathogens at early stages of infection and may help control diseases.

  18. Discrete Emotion Regulation Strategy Repertoires and Parasympathetic Physiology Characterize Psychopathology Symptoms in Childhood

    Science.gov (United States)

    Quiñones-Camacho, Laura E.; Davis, Elizabeth L.

    2018-01-01

    Certain psychopathologies are often linked to dysregulation of specific emotions (e.g., anxiety is associated with dysregulation of fear), but few studies have examined how regulatory repertoires for specific emotions (e.g., the strategies a person uses to regulate fear) relate to psychopathology, and fewer still have examined this in childhood. A…

  19. A regulatory code for neuron-specific odor receptor expression.

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    Anandasankar Ray

    2008-05-01

    Full Text Available Olfactory receptor neurons (ORNs must select-from a large repertoire-which odor receptors to express. In Drosophila, most ORNs express one of 60 Or genes, and most Or genes are expressed in a single ORN class in a process that produces a stereotyped receptor-to-neuron map. The construction of this map poses a problem of receptor gene regulation that is remarkable in its dimension and about which little is known. By using a phylogenetic approach and the genome sequences of 12 Drosophila species, we systematically identified regulatory elements that are evolutionarily conserved and specific for individual Or genes of the maxillary palp. Genetic analysis of these elements supports a model in which each receptor gene contains a zip code, consisting of elements that act positively to promote expression in a subset of ORN classes, and elements that restrict expression to a single ORN class. We identified a transcription factor, Scalloped, that mediates repression. Some elements are used in other chemosensory organs, and some are conserved upstream of axon-guidance genes. Surprisingly, the odor response spectra and organization of maxillary palp ORNs have been extremely well-conserved for tens of millions of years, even though the amino acid sequences of the receptors are not highly conserved. These results, taken together, define the logic by which individual ORNs in the maxillary palp select which odor receptors to express.

  20. The mammary gland-specific marsupial ELP and eutherian CTI share a common ancestral gene.

    Science.gov (United States)

    Pharo, Elizabeth A; De Leo, Alison A; Renfree, Marilyn B; Thomson, Peter C; Lefèvre, Christophe M; Nicholas, Kevin R

    2012-06-08

    The marsupial early lactation protein (ELP) gene is expressed in the mammary gland and the protein is secreted into milk during early lactation (Phase 2A). Mature ELP shares approximately 55.4% similarity with the colostrum-specific bovine colostrum trypsin inhibitor (CTI) protein. Although ELP and CTI both have a single bovine pancreatic trypsin inhibitor (BPTI)-Kunitz domain and are secreted only during the early lactation phases, their evolutionary history is yet to be investigated. Tammar ELP was isolated from a genomic library and the fat-tailed dunnart and Southern koala ELP genes cloned from genomic DNA. The tammar ELP gene was expressed only in the mammary gland during late pregnancy (Phase 1) and early lactation (Phase 2A). The opossum and fat-tailed dunnart ELP and cow CTI transcripts were cloned from RNA isolated from the mammary gland and dog CTI from cells in colostrum. The putative mature ELP and CTI peptides shared 44.6%-62.2% similarity. In silico analyses identified the ELP and CTI genes in the other species examined and provided compelling evidence that they evolved from a common ancestral gene. In addition, whilst the eutherian CTI gene was conserved in the Laurasiatherian orders Carnivora and Cetartiodactyla, it had become a pseudogene in others. These data suggest that bovine CTI may be the ancestral gene of the Artiodactyla-specific, rapidly evolving chromosome 13 pancreatic trypsin inhibitor (PTI), spleen trypsin inhibitor (STI) and the five placenta-specific trophoblast Kunitz domain protein (TKDP1-5) genes. Marsupial ELP and eutherian CTI evolved from an ancestral therian mammal gene before the divergence of marsupials and eutherians between 130 and 160 million years ago. The retention of the ELP gene in marsupials suggests that this early lactation-specific milk protein may have an important role in the immunologically naïve young of these species.

  1. Maximum-Entropy Models of Sequenced Immune Repertoires Predict Antigen-Antibody Affinity.

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    Lorenzo Asti

    2016-04-01

    Full Text Available The immune system has developed a number of distinct complex mechanisms to shape and control the antibody repertoire. One of these mechanisms, the affinity maturation process, works in an evolutionary-like fashion: after binding to a foreign molecule, the antibody-producing B-cells exhibit a high-frequency mutation rate in the genome region that codes for the antibody active site. Eventually, cells that produce antibodies with higher affinity for their cognate antigen are selected and clonally expanded. Here, we propose a new statistical approach based on maximum entropy modeling in which a scoring function related to the binding affinity of antibodies against a specific antigen is inferred from a sample of sequences of the immune repertoire of an individual. We use our inference strategy to infer a statistical model on a data set obtained by sequencing a fairly large portion of the immune repertoire of an HIV-1 infected patient. The Pearson correlation coefficient between our scoring function and the IC50 neutralization titer measured on 30 different antibodies of known sequence is as high as 0.77 (p-value 10-6, outperforming other sequence- and structure-based models.

  2. Sex-specific gonadal and gene expression changes throughout development in fathead minnow

    Science.gov (United States)

    Although fathead minnows (Pimephales promelas) are commonly used as a model fish in endocrine disruption studies, none have characterized sex-specific baseline expression of genes involved in sex differentiation during development in this species. Using a sex-linked DNA marker t...

  3. A Gene Catalogue of the Euchromatic Male-Specific Region of the Horse Y Chromosome: Comparison with Human and Other Mammals

    OpenAIRE

    Paria, Nandina; Raudsepp, Terje; Pearks Wilkerson, Alison J.; O'Brien, Patricia C. M.; Ferguson-Smith, Malcom A.; Love, Charles C.; Arnold, Carolyn; Rakestraw, Peter; Murphy, William J.; Chowdhary, Bhanu P.

    2011-01-01

    Studies of the Y chromosome in primates, rodents and carnivores provide compelling evidence that the male specific region of Y (MSY) contains functional genes, many of which have specialized roles in spermatogenesis and male-fertility. Little similarity, however, has been found between the gene content and sequence of MSY in different species. This hinders the discovery of species-specific male fertility genes and limits our understanding about MSY evolution in mammals. Here, a detailed MSY g...

  4. Polyphyly and gene flow between non-sibling Heliconius species

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    Jiggins Chris D

    2006-04-01

    Full Text Available Abstract Background The view that gene flow between related animal species is rare and evolutionarily unimportant largely antedates sensitive molecular techniques. Here we use DNA sequencing to investigate a pair of morphologically and ecologically divergent, non-sibling butterfly species, Heliconius cydno and H. melpomene (Lepidoptera: Nymphalidae, whose distributions overlap in Central and Northwestern South America. Results In these taxa, we sequenced 30–45 haplotypes per locus of a mitochondrial region containing the genes for cytochrome oxidase subunits I and II (CoI/CoII, and intron-spanning fragments of three unlinked nuclear loci: triose-phosphate isomerase (Tpi, mannose-6-phosphate isomerase (Mpi and cubitus interruptus (Ci genes. A fifth gene, dopa decarboxylase (Ddc produced sequence data likely to be from different duplicate loci in some of the taxa, and so was excluded. Mitochondrial and Tpi genealogies are consistent with reciprocal monophyly, whereas sympatric populations of the species in Panama share identical or similar Mpi and Ci haplotypes, giving rise to genealogical polyphyly at the species level despite evidence for rapid sequence divergence at these genes between geographic races of H. melpomene. Conclusion Recent transfer of Mpi haplotypes between species is strongly supported, but there is no evidence for introgression at the other three loci. Our results demonstrate that the boundaries between animal species can remain selectively porous to gene flow long after speciation, and that introgression, even between non-sibling species, can be an important factor in animal evolution. Interspecific gene flow is demonstrated here for the first time in Heliconius and may provide a route for the transfer of switch-gene adaptations for Müllerian mimicry. The results also forcefully demonstrate how reliance on a single locus may give an erroneous picture of the overall genealogical history of speciation and gene flow.

  5. Specific genetic modifications of domestic animals by gene targeting and animal cloning

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    Zhou Jiangfeng

    2003-11-01

    Full Text Available Abstract The technology of gene targeting through homologous recombination has been extremely useful for elucidating gene functions in mice. The application of this technology was thought impossible in the large livestock species until the successful creation of the first mammalian clone "Dolly" the sheep. The combination of the technologies for gene targeting of somatic cells with those of animal cloning made it possible to introduce specific genetic mutations into domestic animals. In this review, the principles of gene targeting in somatic cells and the challenges of nuclear transfer using gene-targeted cells are discussed. The relevance of gene targeting in domestic animals for applications in bio-medicine and agriculture are also examined.

  6. Phenotypic deconstruction of gene circuitry.

    Science.gov (United States)

    Lomnitz, Jason G; Savageau, Michael A

    2013-06-01

    It remains a challenge to obtain a global perspective on the behavioral repertoire of complex nonlinear gene circuits. In this paper, we describe a method for deconstructing complex systems into nonlinear sub-systems, based on mathematically defined phenotypes, which are then represented within a system design space that allows the repertoire of qualitatively distinct phenotypes of the complex system to be identified, enumerated, and analyzed. This method efficiently characterizes large regions of system design space and quickly generates alternative hypotheses for experimental testing. We describe the motivation and strategy in general terms, illustrate its use with a detailed example involving a two-gene circuit with a rich repertoire of dynamic behavior, and discuss experimental means of navigating the system design space.

  7. Phenotypic deconstruction of gene circuitry

    Science.gov (United States)

    Lomnitz, Jason G.; Savageau, Michael A.

    2013-06-01

    It remains a challenge to obtain a global perspective on the behavioral repertoire of complex nonlinear gene circuits. In this paper, we describe a method for deconstructing complex systems into nonlinear sub-systems, based on mathematically defined phenotypes, which are then represented within a system design space that allows the repertoire of qualitatively distinct phenotypes of the complex system to be identified, enumerated, and analyzed. This method efficiently characterizes large regions of system design space and quickly generates alternative hypotheses for experimental testing. We describe the motivation and strategy in general terms, illustrate its use with a detailed example involving a two-gene circuit with a rich repertoire of dynamic behavior, and discuss experimental means of navigating the system design space.

  8. Estimating phylogenetic relationships despite discordant gene trees across loci: the species tree of a diverse species group of feather mites (Acari: Proctophyllodidae).

    Science.gov (United States)

    Knowles, Lacey L; Klimov, Pavel B

    2011-11-01

    With the increased availability of multilocus sequence data, the lack of concordance of gene trees estimated for independent loci has focused attention on both the biological processes producing the discord and the methodologies used to estimate phylogenetic relationships. What has emerged is a suite of new analytical tools for phylogenetic inference--species tree approaches. In contrast to traditional phylogenetic methods that are stymied by the idiosyncrasies of gene trees, approaches for estimating species trees explicitly take into account the cause of discord among loci and, in the process, provides a direct estimate of phylogenetic history (i.e. the history of species divergence, not divergence of specific loci). We illustrate the utility of species tree estimates with an analysis of a diverse group of feather mites, the pinnatus species group (genus Proctophyllodes). Discord among four sequenced nuclear loci is consistent with theoretical expectations, given the short time separating speciation events (as evident by short internodes relative to terminal branch lengths in the trees). Nevertheless, many of the relationships are well resolved in a Bayesian estimate of the species tree; the analysis also highlights ambiguous aspects of the phylogeny that require additional loci. The broad utility of species tree approaches is discussed, and specifically, their application to groups with high speciation rates--a history of diversification with particular prevalence in host/parasite systems where species interactions can drive rapid diversification.

  9. Endogenous retroviruses function as species-specific enhancer elements in the placenta.

    Science.gov (United States)

    Chuong, Edward B; Rumi, M A Karim; Soares, Michael J; Baker, Julie C

    2013-03-01

    The mammalian placenta is remarkably distinct between species, suggesting a history of rapid evolutionary diversification. To gain insight into the molecular drivers of placental evolution, we compared biochemically predicted enhancers in mouse and rat trophoblast stem cells (TSCs) and found that species-specific enhancers are highly enriched for endogenous retroviruses (ERVs) on a genome-wide level. One of these ERV families, RLTR13D5, contributes hundreds of mouse-specific histone H3 lysine 4 monomethylation (H3K4me1)- and histone H3 lysine 27 acetylation (H3K27ac)-defined enhancers that functionally bind Cdx2, Eomes and Elf5-core factors that define the TSC regulatory network. Furthermore, we show that RLTR13D5 is capable of driving gene expression in rat placental cells. Analysis in other tissues shows that species-specific ERV enhancer activity is generally restricted to hypomethylated tissues, suggesting that tissues permissive for ERV activity gain access to an otherwise silenced source of regulatory variation. Overall, our results implicate ERV enhancer co-option as a mechanism underlying the extensive evolutionary diversification of placental development.

  10. Species-specific detection and quantification of common barnacle larvae from the Japanese coast using quantitative real-time PCR.

    Science.gov (United States)

    Endo, Noriyuki; Sato, Kana; Matsumura, Kiyotaka; Yoshimura, Erina; Odaka, Yukiko; Nogata, Yasuyuki

    2010-11-01

    Species-specific detection and quantification methods for barnacle larvae using quantitative real-time polymerase chain reaction (qPCR) were developed. Species-specific primers for qPCR were designed for 13 barnacle species in the mitochondrial 12S ribosomal RNA gene region. Primer specificity was examined by PCR using template DNA extracted from each of the 13 barnacle species, other unidentified barnacle species, and field collected zooplankton samples. The resulting PCR products comprised single bands following agarose gel electrophoresis when the templates corresponded to primers. The amplifications were highly species-specific even for the field plankton samples. The field plankton samples were subjected to qPCR assay. The calculated DNA contents for each barnacle species were closely correlated with the number of larvae measured by microscopic examination. The method could be applied to quantify barnacle larvae in natural plankton samples.

  11. Norepinephrine-induced apoptotic and hypertrophic responses in H9c2 cardiac myoblasts are characterized by different repertoire of reactive oxygen species generation

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    Anita Thakur

    2015-08-01

    Full Text Available Despite recent advances, the role of ROS in mediating hypertrophic and apoptotic responses in cardiac myocytes elicited by norepinephrine (NE is rather poorly understood. We demonstrate through our experiments that H9c2 cardiac myoblasts treated with 2 µM NE (hypertrophic dose generate DCFH-DA positive ROS only for 2 h; while those treated with 100 µM NE (apoptotic dose sustains generation for 48 h, followed by apoptosis. Though the levels of DCFH fluorescence were comparable at early time points in the two treatment sets, its quenching by DPI, catalase and MnTmPyP suggested the existence of a different repertoire of ROS. Both doses of NE also induced moderate levels of H2O2 but with different kinetics. Sustained but intermittent generation of highly reactive species detectable by HPF was seen in both treatment sets but no peroxynitrite was generated in either conditions. Sustained generation of hydroxyl radicals with no appreciable differences were noticed in both treatment sets. Nevertheless, despite similar profile of ROS generation between the two conditions, extensive DNA damage as evident from the increase in 8-OH-dG content, formation of γ-H2AX and PARP cleavage was seen only in cells treated with the higher dose of NE. We therefore conclude that hypertrophic and apoptotic doses of NE generate distinct but comparable repertoire of ROS/RNS leading to two very distinct downstream responses.

  12. Identification of a novel Gig2 gene family specific to non-amniote vertebrates.

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    Yi-Bing Zhang

    Full Text Available Gig2 (grass carp reovirus (GCRV-induced gene 2 is first identified as a novel fish interferon (IFN-stimulated gene (ISG. Overexpression of a zebrafish Gig2 gene can protect cultured fish cells from virus infection. In the present study, we identify a novel gene family that is comprised of genes homologous to the previously characterized Gig2. EST/GSS search and in silico cloning identify 190 Gig2 homologous genes in 51 vertebrate species ranged from lampreys to amphibians. Further large-scale search of vertebrate and invertebrate genome databases indicate that Gig2 gene family is specific to non-amniotes including lampreys, sharks/rays, ray-finned fishes and amphibians. Phylogenetic analysis and synteny analysis reveal lineage-specific expansion of Gig2 gene family and also provide valuable evidence for the fish-specific genome duplication (FSGD hypothesis. Although Gig2 family proteins exhibit no significant sequence similarity to any known proteins, a typical Gig2 protein appears to consist of two conserved parts: an N-terminus that bears very low homology to the catalytic domains of poly(ADP-ribose polymerases (PARPs, and a novel C-terminal domain that is unique to this gene family. Expression profiling of zebrafish Gig2 family genes shows that some duplicate pairs have diverged in function via acquisition of novel spatial and/or temporal expression under stresses. The specificity of this gene family to non-amniotes might contribute to a large extent to distinct physiology in non-amniote vertebrates.

  13. Detection of pork adulteration in processed meat by species-specific PCR-QIAxcel procedure based on D-loop and cytb genes.

    Science.gov (United States)

    Barakat, Hassan; El-Garhy, Hoda A S; Moustafa, Mahmoud M A

    2014-12-01

    Detection of pork meat adulteration in "halal" meat products is a crucial issue in the fields of modern food inspection according to implementation of very strict procedures for halal food labelling. Present study aims at detecting and quantifying pork adulteration in both raw and cooked manufactured sausages. This is by applying an optimized species-specific PCR procedure followed by QIAxcel capillary electrophoresis system. Manufacturing experiment was designed by incorporating pork with beef meat at 0.01 to 10 % substitution levels beside beef and pork sausages as negative and positive controls, respectively. Subsequently, sausages were divided into raw and cooked sausages then subjected to DNA extraction. Results indicated that PCR amplifications of mitochondrial D-loop and cytochrome b (cytb) genes by porcine-specific primers produced 185 and 117 bp pork-specific DNA fragments in sausages, respectively. No DNA fragments were detected when PCR was applied on beef sausage DNA confirming primers specificity. For internal control, a 141-bp DNA fragment of eukaryotic 18S ribosomal RNA (rRNA) gene was amplified from pork and beef DNA templates. Although PCR followed by either QIAxcel or agarose techniques were efficient for targeted DNA fragments differentiation even as low as 0.01 % (pork/meat: w/w). For proficiency, adequacy, and performance, PCR-QIA procedure is highly sensitive, a time-saver, electronically documented, mutagenic-reagent free, of little manual errors, accurate in measuring PCR fragments length, and quantitative data supplier. In conclusion, it can be suggested that optimized PCR-QAI is considered as a rapid and sensitive method for routine pork detection and quantification in raw or processed meat.

  14. Beyond Agrobacterium-Mediated Transformation: Horizontal Gene Transfer from Bacteria to Eukaryotes.

    Science.gov (United States)

    Lacroix, Benoît; Citovsky, Vitaly

    2018-03-03

    Besides the massive gene transfer from organelles to the nuclear genomes, which occurred during the early evolution of eukaryote lineages, the importance of horizontal gene transfer (HGT) in eukaryotes remains controversial. Yet, increasing amounts of genomic data reveal many cases of bacterium-to-eukaryote HGT that likely represent a significant force in adaptive evolution of eukaryotic species. However, DNA transfer involved in genetic transformation of plants by Agrobacterium species has traditionally been considered as the unique example of natural DNA transfer and integration into eukaryotic genomes. Recent discoveries indicate that the repertoire of donor bacterial species and of recipient eukaryotic hosts potentially are much wider than previously thought, including donor bacterial species, such as plant symbiotic nitrogen-fixing bacteria (e.g., Rhizobium etli) and animal bacterial pathogens (e.g., Bartonella henselae, Helicobacter pylori), and recipient species from virtually all eukaryotic clades. Here, we review the molecular pathways and potential mechanisms of these trans-kingdom HGT events and discuss their utilization in biotechnology and research.

  15. Gene expression profiling of non-polyadenylated RNA-seq across species

    Directory of Open Access Journals (Sweden)

    Xiao-Ou Zhang

    2014-12-01

    Full Text Available Transcriptomes are dynamic and unique, with each cell type/tissue, developmental stage and species expressing a different repertoire of RNA transcripts. Most mRNAs and well-characterized long noncoding RNAs are shaped with a 5′ cap and 3′ poly(A tail, thus conventional transcriptome analyses typically start with the enrichment of poly(A+ RNAs by oligo(dT selection, followed by deep sequencing approaches. However, accumulated lines of evidence suggest that many RNA transcripts are processed by alternative mechanisms without 3′ poly(A tails and, therefore, fail to be enriched by oligo(dT purification and are absent following deep sequencing analyses. We have described an enrichment strategy to purify non-polyadenylated (poly(A−/ribo− RNAs from human total RNAs by removal of both poly(A+ RNA transcripts and ribosomal RNAs, which led to the identification of many novel RNA transcripts with non-canonical 3′ ends in human. Here, we describe the application of non-polyadenylated RNA-sequencing in rhesus monkey and mouse cell lines/tissue, and further profile the transcription of non-polyadenylated RNAs across species, providing new resources for non-polyadenylated RNA identification and comparison across species.

  16. Halal authenticity of gelatin using species-specific PCR.

    Science.gov (United States)

    Shabani, Hessam; Mehdizadeh, Mehrangiz; Mousavi, Seyed Mohammad; Dezfouli, Ehsan Ansari; Solgi, Tara; Khodaverdi, Mahdi; Rabiei, Maryam; Rastegar, Hossein; Alebouyeh, Mahmoud

    2015-10-01

    Consumption of food products derived from porcine sources is strictly prohibited in Islam. Gelatin, mostly derived from bovine and porcine sources, has many applications in the food and pharmaceutical industries. To ensure that food products comply with halal regulations, development of valid and reliable analytical methods is very much required. In this study, a species-specific polymerase chain reaction (PCR) assay using conserved regions of mitochondrial DNA (cytochrome b gene) was performed to evaluate the halal authenticity of gelatin. After isolation of DNA from gelatin powders with known origin, conventional PCR using species-specific primers was carried out on the extracted DNA. The amplified expected PCR products of 212 and 271 bp were observed for porcine and bovine gelatin, respectively. The sensitivity of the method was tested on binary gelatin mixtures containing 0.1%, 1%, 10%, and 100% (w/w) of porcine gelatin within bovine gelatin and vice versa. Although most of the DNA is degraded due to the severe processing steps of gelatin production, the minimum level of 0.1% w/w of both porcine and bovine gelatin was detected. Moreover, eight food products labeled as containing bovine gelatin and eight capsule shells were subjected to PCR examination. The results showed that all samples contained bovine gelatin, and the absence of porcine gelatin was verified. This method of species authenticity is very useful to verify whether gelatin and gelatin-containing food products are derived from halal ingredients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. VLADIMIR AXIONOV ABOUT GHEORGHE NEAGADS COMPONISTIC REPERTOIRE

    Directory of Open Access Journals (Sweden)

    CHICIUC NATALIA

    2015-03-01

    Full Text Available This article presents one side of Vladimir Axionov’s scientific research, namely the one referring to Gheorghe NeagaUs componistic repertoire. A frequent analysis of Gh. NeagaUs works, practically, all the musicologyst’s studies, separately or together with the works of other authors, show that this composer’s repertoire played an important role in the creative processes occurring in Moldovan music, Gheorghe Neaga exemplifying many trends that have emerged in native composition.

  18. Identification of pathogenic Nocardia species by reverse line blot hybridization targeting the 16S rRNA and 16S-23S rRNA gene spacer regions.

    Science.gov (United States)

    Xiao, Meng; Kong, Fanrong; Sorrell, Tania C; Cao, Yongyan; Lee, Ok Cha; Liu, Ying; Sintchenko, Vitali; Chen, Sharon C A

    2010-02-01

    Although 16S rRNA gene sequence analysis is employed most often for the definitive identification of Nocardia species, alternate molecular methods and polymorphisms in other gene targets have also enabled species determinations. We evaluated a combined Nocardia PCR-based reverse line blot (RLB) hybridization assay based on 16S and 16S-23S rRNA gene spacer region polymorphisms to identify 12 American Type Culture Collection and 123 clinical Nocardia isolates representing 14 species; results were compared with results from 16S rRNA gene sequencing. Thirteen 16S rRNA gene-based (two group-specific and 11 species-specific) and five 16S-23S spacer-targeted (two taxon-specific and three species-specific) probes were utilized. 16S rRNA gene-based probes correctly identified 124 of 135 isolates (sensitivity, 92%) but were unable to identify Nocardia paucivorans strains (n = 10 strains) and a Nocardia asteroides isolate with a novel 16S rRNA gene sequence. Nocardia farcinica and Nocardia cyriacigeorgica strains were identified by the sequential use of an N. farcinica-"negative" probe and a combined N. farcinica/N. cyriacigeorgica probe. The assay specificity was high (99%) except for weak cross-reactivity between the Nocardia brasiliensis probe with the Nocardia thailandica DNA product; however, cross-hybridization with closely related nontarget species may occur. The incorporation of 16S-23S rRNA gene spacer-based probes enabled the identification of all N. paucivorans strains. The overall sensitivity using both probe sets was >99%. Both N. farcinica-specific 16S-23S rRNA gene spacer-directed probes were required to identify all N. farcinica stains by using this probe set. The study demonstrates the utility of a combined PCR/RLB assay for the identification of clinically relevant Nocardia species and its potential for studying subtypes of N. farcinica. Where species assignment is ambiguous or not possible, 16S rRNA gene sequencing is recommended.

  19. The mammary gland-specific marsupial ELP and eutherian CTI share a common ancestral gene

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    Pharo Elizabeth A

    2012-06-01

    Full Text Available Abstract Background The marsupial early lactation protein (ELP gene is expressed in the mammary gland and the protein is secreted into milk during early lactation (Phase 2A. Mature ELP shares approximately 55.4% similarity with the colostrum-specific bovine colostrum trypsin inhibitor (CTI protein. Although ELP and CTI both have a single bovine pancreatic trypsin inhibitor (BPTI-Kunitz domain and are secreted only during the early lactation phases, their evolutionary history is yet to be investigated. Results Tammar ELP was isolated from a genomic library and the fat-tailed dunnart and Southern koala ELP genes cloned from genomic DNA. The tammar ELP gene was expressed only in the mammary gland during late pregnancy (Phase 1 and early lactation (Phase 2A. The opossum and fat-tailed dunnart ELP and cow CTI transcripts were cloned from RNA isolated from the mammary gland and dog CTI from cells in colostrum. The putative mature ELP and CTI peptides shared 44.6%-62.2% similarity. In silico analyses identified the ELP and CTI genes in the other species examined and provided compelling evidence that they evolved from a common ancestral gene. In addition, whilst the eutherian CTI gene was conserved in the Laurasiatherian orders Carnivora and Cetartiodactyla, it had become a pseudogene in others. These data suggest that bovine CTI may be the ancestral gene of the Artiodactyla-specific, rapidly evolving chromosome 13 pancreatic trypsin inhibitor (PTI, spleen trypsin inhibitor (STI and the five placenta-specific trophoblast Kunitz domain protein (TKDP1-5 genes. Conclusions Marsupial ELP and eutherian CTI evolved from an ancestral therian mammal gene before the divergence of marsupials and eutherians between 130 and 160 million years ago. The retention of the ELP gene in marsupials suggests that this early lactation-specific milk protein may have an important role in the immunologically naïve young of these species.

  20. IDENTIFIKASI DAGING BABI MENGGUNAKAN METODE PCR-RFLP GEN Cytochrome b DAN PCR PRIMER SPESIFIK GEN AMELOGENIN (Pork Identification Using PCR-RFLP of Cytochrome b Gene and Species Specific PCR of Amelogenin Gene

    Directory of Open Access Journals (Sweden)

    Yuny Erwanto

    2013-03-01

    Full Text Available A polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP and species specific PCR methods had been applied for identifying pork in mixture of meat. Pork sample in various levels (1, 3, 5 and 10% was prepared in mixture with beef, chicken and mutton. The primary CYTb1 and CYTb2 were designed in the mitochondrial cytochrome b b (cytochrome b gene and PCR successfully amplified fragments of 359 bp. To distinguish pig species existence, the amplified PCR products of mitochondrial DNA were cut by BseDI restriction enzyme. The result showed that pig mitochondrial DNA was cut into 131 and 228 bp fragments. A polymerase chain reaction (PCR method based on the nucleotide sequence variation in the amelogenin gene has been chosen for the specific identification of pork DNAs in mixture meat. The primers designed generated specific fragments of 353 and 312 bp length for pork. The specificity of the primary designed was tested on 4 animal species including pig, cattle, chicken and goat species. Analysis of experimental mixture meat demonstrated that 1% of raw pork tissues could be detected using PCR-RFLP with BseDI restriction enzyme but detection using species-specific PCR showed the cross reactivity to beef, chicken and mutton. The cytochrome b PCR-RFLP species identification assay yielded excellent results for identification of pig species. PCR-RFLP is a potentially reliable technique for detection of the existence of pork in animal food product for Halal authentication. Keywords: Pork identification, cytochrome b, amelogenin, polymerase chain reaction   ABSTRAK   Penelitian ini dilakukan untuk mengaplikasikan metode deteksi daging babi dalam campuan daging dengan sapi, kambing dan ayam melalui PCR-RFLP dan PCR dengan primer spesifik untuk babi. Level kontaminasi daging babi dibuat sebesar 1, 3, 5 dan 10% dari total daging dalam campuran. Metode PCR-RFLP menggunakan sepasang primer yaitu gen cytochrome b dari mitokondria yang

  1. Reliable cloning of functional antibody variable domains from hybridomas and spleen cell repertoires employing a reengineered phage display system.

    Science.gov (United States)

    Krebber, A; Bornhauser, S; Burmester, J; Honegger, A; Willuda, J; Bosshard, H R; Plückthun, A

    1997-02-14

    A prerequisite for the use of recombinant antibody technologies starting from hybridomas or immune repertoires is the reliable cloning of functional immunoglobulin genes. For this purpose, a standard phage display system was optimized for robustness, vector stability, tight control of scFv-delta geneIII expression, primer usage for PCR amplification of variable region genes, scFv assembly strategy and subsequent directional cloning using a single rare cutting restriction enzyme. This integrated cloning, screening and selection system allowed us to rapidly obtain antigen binding scFvs derived from spleen-cell repertoires of mice immunized with ampicillin as well as from all hybridoma cell lines tested to date. As representative examples, cloning of monoclonal antibodies against a his tag, leucine zippers, the tumor marker EGP-2 and the insecticide DDT is presented. Several hybridomas whose genes could not be cloned in previous experimental setups, but were successfully obtained with the present system, expressed high amounts of aberrant heavy and light chain mRNAs, which were amplified by PCR and greatly exceeded the amount of binding antibody sequences. These contaminating variable region genes were successfully eliminated by employing the optimized phage display system, thus avoiding time consuming sequencing of non-binding scFv genes. To maximize soluble expression of functional scFvs subsequent to cloning, a compatible vector series to simplify modification, detection, multimerization and rapid purification of recombinant antibody fragments was constructed.

  2. Finding novel relationships with integrated gene-gene association network analysis of Synechocystis sp. PCC 6803 using species-independent text-mining.

    Science.gov (United States)

    Kreula, Sanna M; Kaewphan, Suwisa; Ginter, Filip; Jones, Patrik R

    2018-01-01

    The increasing move towards open access full-text scientific literature enhances our ability to utilize advanced text-mining methods to construct information-rich networks that no human will be able to grasp simply from 'reading the literature'. The utility of text-mining for well-studied species is obvious though the utility for less studied species, or those with no prior track-record at all, is not clear. Here we present a concept for how advanced text-mining can be used to create information-rich networks even for less well studied species and apply it to generate an open-access gene-gene association network resource for Synechocystis sp. PCC 6803, a representative model organism for cyanobacteria and first case-study for the methodology. By merging the text-mining network with networks generated from species-specific experimental data, network integration was used to enhance the accuracy of predicting novel interactions that are biologically relevant. A rule-based algorithm (filter) was constructed in order to automate the search for novel candidate genes with a high degree of likely association to known target genes by (1) ignoring established relationships from the existing literature, as they are already 'known', and (2) demanding multiple independent evidences for every novel and potentially relevant relationship. Using selected case studies, we demonstrate the utility of the network resource and filter to ( i ) discover novel candidate associations between different genes or proteins in the network, and ( ii ) rapidly evaluate the potential role of any one particular gene or protein. The full network is provided as an open-source resource.

  3. Characterization of abiotic stress genes from different species of eucalyptus

    International Nuclear Information System (INIS)

    Naz, S.; Kausar, H.; Saleem, F.; Zafarullah, A.

    2015-01-01

    The stresses causing dehydration damage to the plant cell like cold, drought, and high salinity are the most frequent environmental stresses that influence plant growth, development and restraining productivity in cultivated areas world-wide. Many drought, salinity and cold inducible genes causing tolerance to environmental stresses in many plants include Dehydrin1 (DHN1), Dehydrin2 (DHN2), Dehydrin10 (DHN10), putative phosphate transporter (Ecpt2), choline monooxygenase (CMO) and DREB/CBF1c genes. Gene specific primer pairs were designed for each gene using DNAStar software. These genes were amplified from different species of eucalyptus such as Eucalyptus camaldulensis, E. globulus, E. tereticornis and E. gunii through PCR. Dehydrin2 gene of E. camaldulensis and dehydrin10 gene of E. globulus were cloned using the TA Cloning Kit with pCR 2.1 vector and sequenced. The Dehydrin genes sequences were submitted to GeneBank: Eucalyptus globulus dehydrin10 gene (Accession No. HG915712) and E. camaldulensis dehydrin 2 gene (Accession No. HG813113). The amino acid sequence of Dehydrin10 from E. globulus showed 97% homology to E. globulus DHN10 (JN052210) and Dehydrin2 from E. camaldulensis presented 94% homology to E. globulus DHN2 (JN052209). These genes can be employed in generating drought resistant crop plants. (author)

  4. Taxonomically restricted genes are associated with the evolution of sociality in the honey bee

    Directory of Open Access Journals (Sweden)

    Tsutsui Neil D

    2011-03-01

    Full Text Available Abstract Background Studies have shown that taxonomically restricted genes are significant in number and important for the evolution of lineage specific traits. Social insects have gained many novel morphological and behavioral traits relative to their solitary ancestors. The task repertoire of an advanced social insect, for example, can be 40-50 tasks, about twice that of a solitary wasp or bee. The genetic basis of this expansion in behavioral repertoire is still poorly understood, and a role for taxonomically restricted genes has not been explored at the whole genome level. Results Here we present comparative genomics results suggesting that taxonomically restricted genes may have played an important role in generating the expansion of behavioral repertoire associated with the evolution of eusociality. First, we show that the current honey bee official gene set contains about 700 taxonomically restricted genes. These are split between orphans, genes found only in the Hymenoptera, and genes found only in insects. Few of the orphans or genes restricted to the Hymenoptera have been the focus of experimental work, but several of those that have are associated with novel eusocial traits or traits thought to have changed radically as a consequence of eusociality. Second, we predicted that if taxonomically restricted genes are important for generating novel eusocial traits, then they should be expressed with greater frequency in workers relative to the queen, as the workers exhibit most of the novel behavior of the honey bee relative to their solitary ancestors. We found support for this prediction. Twice as many taxonomically restricted genes were found amongst the genes with higher expression in workers compared to those with higher expression in queens. Finally, we compiled an extensive list of candidate taxonomically restricted genes involved in eusocial evolution by analyzing several caste specific gene expression data sets. Conclusions This

  5. VH repertoire in progeny of long term lymphoid-cultured cells used to reconstitute immunodeficient mice

    International Nuclear Information System (INIS)

    Denis, K.A.; Timson, L.K.; Witte, O.N.

    1989-01-01

    VH gene utilization in the progeny of long term lymphoid-cultured cells used for reconstitution of severe combined immunodeficient mice under varying conditions was determined. Hybridomas made from the spleens of these animals were evaluated for clonality and donor origin and a panel of 146 independent hybridomas were subsequently examined for VH expression. Hybridomas derived from the spleens of SCID mice reconstituted with fresh cells, used as a control, utilized VH families in proportion to their numerical representation in the genome. However, hybridomas from the spleens of mice reconstituted with long term cultured cells utilized a predominance of the two VH gene families most proximal to JH, characteristic of cells early in B lymphocyte development. Coinjection of thymocytes with cultured fetal liver cells, to provide good levels of T lymphocytes, did not alter this pattern of VH utilization. Irradiation (3 Gy) of the mice before cultured cell injection, which leads to more complete reconstitution of the B cell compartment, was effective in removing this bias in the VH repertoire. Hybridomas derived from these mice expressed their VH genes more in proportion to family size, characteristic of cells later in B lymphocyte development. In this manner, long term lymphoid-cultured cells can be used to study the transitions that occur in VH repertoire expression which appear to be mediated by either B lymphocyte developmental microenvironment or population size

  6. BRD4 localization to lineage-specific enhancers is associated with a distinct transcription factor repertoire

    OpenAIRE

    Najafova, Zeynab; Tirado-Magallanes, Roberto; Subramaniam, Malayannan; Hossan, Tareq; Schmidt, Geske; Nagarajan, Sankari; Baumgart, Simon J.; Mishra, Vivek?Kumar; Bedi, Upasana; Hesse, Eric; Knapp, Stefan; Hawse, John R.; Johnsen, Steven A.

    2016-01-01

    Proper temporal epigenetic regulation of gene expression is essential for cell fate determination and tissue development. The Bromodomain-containing Protein-4 (BRD4)was previously shown to control the transcription of defined subsets of genes in various cell systems. In this study we examined the role of BRD4 in promoting lineage-specific gene expression and show that BRD4 is essential for osteoblast differentiation. Genome-wide analyses demonstrate that BRD4 is rec...

  7. Interspecific gene flow and maintenance of species integrity in oaks

    Directory of Open Access Journals (Sweden)

    Oliver Gailing

    2014-07-01

    Full Text Available Oak species show a wide variation in morphological and physiological characters, and species boundaries between closely related species are often not clear-cut. Still, despite frequent interspecific gene flow, oaks maintain distinct morphological and physiological adaptations. In sympatric stands, spatial distribution of species with different ecological requirements is not random but constrained by soil and other microenvironmental factors. Pre-zygotic isolation (e.g. cross incompatibilities, asynchrony in flowering, pollen competition and post-zygotic isolation (divergent selection contribute to the maintenance of species integrity in sympatric oak stands. The antagonistic effects of interspecific gene flow and divergent selection are reflected in the low genetic differentiation between hybridizing oak species at most genomic regions interspersed by regions with signatures of divergent selection (outlier regions. In the near future, the availability of high-density genetic linkage maps anchored to scaffolds of a sequenced Q. robur genome will allow to characterize the underlying genes in these outlier regions and their putative role in reproductive isolation between species. Reciprocal transplant experiments of seedlings between parental environments can be used to characterize selection on outlier genes. High transferability of gene-based markers will enable comparative outlier screens in different oak species.

  8. eap Gene as novel target for specific identification of Staphylococcus aureus.

    Science.gov (United States)

    Hussain, Muzaffar; von Eiff, Christof; Sinha, Bhanu; Joost, Insa; Herrmann, Mathias; Peters, Georg; Becker, Karsten

    2008-02-01

    The cell surface-associated extracellular adherence protein (Eap) mediates adherence of Staphylococcus aureus to host extracellular matrix components and inhibits inflammation, wound healing, and angiogenesis. A well-characterized collection of S. aureus and non-S. aureus staphylococcal isolates (n = 813) was tested for the presence of the Eap-encoding gene (eap) by PCR to investigate the use of the eap gene as a specific diagnostic tool for identification of S. aureus. Whereas all 597 S. aureus isolates were eap positive, this gene was not detectable in 216 non-S. aureus staphylococcal isolates comprising 47 different species and subspecies of coagulase-negative staphylococci and non-S. aureus coagulase-positive or coagulase-variable staphylococci. Furthermore, non-S. aureus isolates did not express Eap homologs, as verified on the transcriptional and protein levels. Based on these data, the sensitivity and specificity of the newly developed PCR targeting the eap gene were both 100%. Thus, the unique occurrence of Eap in S. aureus offers a promising tool particularly suitable for molecular diagnostics of this pathogen.

  9. Parallel habitat acclimatization is realized by the expression of different genes in two closely related salamander species (genus Salamandra).

    Science.gov (United States)

    Goedbloed, D J; Czypionka, T; Altmüller, J; Rodriguez, A; Küpfer, E; Segev, O; Blaustein, L; Templeton, A R; Nolte, A W; Steinfartz, S

    2017-12-01

    The utilization of similar habitats by different species provides an ideal opportunity to identify genes underlying adaptation and acclimatization. Here, we analysed the gene expression of two closely related salamander species: Salamandra salamandra in Central Europe and Salamandra infraimmaculata in the Near East. These species inhabit similar habitat types: 'temporary ponds' and 'permanent streams' during larval development. We developed two species-specific gene expression microarrays, each targeting over 12 000 transcripts, including an overlapping subset of 8331 orthologues. Gene expression was examined for systematic differences between temporary ponds and permanent streams in larvae from both salamander species to establish gene sets and functions associated with these two habitat types. Only 20 orthologues were associated with a habitat in both species, but these orthologues did not show parallel expression patterns across species more than expected by chance. Functional annotation of a set of 106 genes with the highest effect size for a habitat suggested four putative gene function categories associated with a habitat in both species: cell proliferation, neural development, oxygen responses and muscle capacity. Among these high effect size genes was a single orthologue (14-3-3 protein zeta/YWHAZ) that was downregulated in temporary ponds in both species. The emergence of four gene function categories combined with a lack of parallel expression of orthologues (except 14-3-3 protein zeta) suggests that parallel habitat adaptation or acclimatization by larvae from S. salamandra and S. infraimmaculata to temporary ponds and permanent streams is mainly realized by different genes with a converging functionality.

  10. Nomadic enhancers: tissue-specific cis-regulatory elements of yellow have divergent genomic positions among Drosophila species.

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    Gizem Kalay

    2010-11-01

    Full Text Available cis-regulatory DNA sequences known as enhancers control gene expression in space and time. They are central to metazoan development and are often responsible for changes in gene regulation that contribute to phenotypic evolution. Here, we examine the sequence, function, and genomic location of enhancers controlling tissue- and cell-type specific expression of the yellow gene in six Drosophila species. yellow is required for the production of dark pigment, and its expression has evolved largely in concert with divergent pigment patterns. Using Drosophila melanogaster as a transgenic host, we examined the expression of reporter genes in which either 5' intergenic or intronic sequences of yellow from each species controlled the expression of Green Fluorescent Protein. Surprisingly, we found that sequences controlling expression in the wing veins, as well as sequences controlling expression in epidermal cells of the abdomen, thorax, and wing, were located in different genomic regions in different species. By contrast, sequences controlling expression in bristle-associated cells were located in the intron of all species. Differences in the precise pattern of spatial expression within the developing epidermis of D. melanogaster transformants usually correlated with adult pigmentation in the species from which the cis-regulatory sequences were derived, which is consistent with cis-regulatory evolution affecting yellow expression playing a central role in Drosophila pigmentation divergence. Sequence comparisons among species favored a model in which sequential nucleotide substitutions were responsible for the observed changes in cis-regulatory architecture. Taken together, these data demonstrate frequent changes in yellow cis-regulatory architecture among Drosophila species. Similar analyses of other genes, combining in vivo functional tests of enhancer activity with in silico comparative genomics, are needed to determine whether the pattern of

  11. Pollen irradiation and possible gene transfer in Nicotiana species

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1985-01-01

    , and Petunia parodii with irradiated pollen from N. alata and Petunia hybrida showed no evidence of gene transfer, nor did experiments with irradiated mentor pollen. This indicates that gene transfer with irradiated pollen between non-crossing species or between species giving sterile hybrids is probably...

  12. The functions of Mediator in Candida albicans support a role in shaping species-specific gene expression.

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    Nathalie Uwamahoro

    Full Text Available The Mediator complex is an essential co-regulator of RNA polymerase II that is conserved throughout eukaryotes. Here we present the first study of Mediator in the pathogenic fungus Candida albicans. We focused on the Middle domain subunit Med31, the Head domain subunit Med20, and Srb9/Med13 from the Kinase domain. The C. albicans Mediator shares some roles with model yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, such as functions in the response to certain stresses and the role of Med31 in the expression of genes regulated by the activator Ace2. The C. albicans Mediator also has additional roles in the transcription of genes associated with virulence, for example genes related to morphogenesis and gene families enriched in pathogens, such as the ALS adhesins. Consistently, Med31, Med20, and Srb9/Med13 contribute to key virulence attributes of C. albicans, filamentation, and biofilm formation; and ALS1 is a biologically relevant target of Med31 for development of biofilms. Furthermore, Med31 affects virulence of C. albicans in the worm infection model. We present evidence that the roles of Med31 and Srb9/Med13 in the expression of the genes encoding cell wall adhesins are different between S. cerevisiae and C. albicans: they are repressors of the FLO genes in S. cerevisiae and are activators of the ALS genes in C. albicans. This suggests that Mediator subunits regulate adhesion in a distinct manner between these two distantly related fungal species.

  13. Broad T-cell receptor repertoire in T-lymphocytes derived from human induced pluripotent stem cells.

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    Chia-Wei Chang

    Full Text Available Human induced pluripotent stem cells (hiPSCs have enormous potential for the treatment of inherited and acquired disorders. Recently, antigen-specific T lymphocytes derived from hiPSCs have been reported. However, T lymphocyte populations with broad T cell receptor (TCR diversity have not been generated. We report that hiPSCs derived from skin biopsy are capable of producing T lymphocyte populations with a broad TCR repertoire. In vitro T cell differentiation follows a similar developmental program as observed in vivo, indicated by sequential expression of CD7, intracellular CD3 and surface CD3. The γδ TCR locus is rearranged first and is followed by rearrangement of the αβ locus. Both γδ and αβ T cells display a diverse TCR repertoire. Upon activation, the cells express CD25, CD69, cytokines (TNF-α, IFN-γ, IL-2 and cytolytic proteins (Perforin and Granzyme-B. These results suggest that most, if not all, mechanisms required to generate functional T cells with a broad TCR repertoire are intact in our in vitro differentiation protocol. These data provide a foundation for production of patient-specific T cells for the treatment of acquired or inherited immune disorders and for cancer immunotherapy.

  14. Is Drosophila-microbe association species-specific or region specific? A study undertaken involving six Indian Drosophila species.

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    Singhal, Kopal; Khanna, Radhika; Mohanty, Sujata

    2017-06-01

    The present work aims to identify the microbial diversity associated with six Indian Drosophila species using next generation sequencing (NGS) technology and to discover the nature of their distribution across species and eco-geographic regions. Whole fly gDNA of six Drosophila species were used to generate sequences in an Illumina platform using NGS technology. De novo based assembled raw reads were blasted against the NR database of NCBI using BLASTn for identification of their bacterial loads. We have tried to include Drosophila species from different taxonomical groups and subgroups and from three different eco-climatic regions India; four species belong to Central India, while the rest two, D. melanogaster and D. ananassae, belong to West and South India to determine both their species-wise and region-wide distribution. We detected the presence of 33 bacterial genera across all six study species, predominated by the class Proteobacteria. Amongst all, D. melanogaster was found to be the most diverse by carrying around 85% of the bacterial diversity. Our findings infer both species-specific and environment-specific nature of the bacterial species inhabiting the Drosophila host. Though the present results are consistent with most of the earlier studies, they also remain incoherent with some. The present study outcome on the host-bacteria association and their species specific adaptation may provide some insight to understand the host-microbial interactions and the phenotypic implications of microbes on the host physiology. The knowledge gained may be importantly applied into the recent insect and pest population control strategy going to implement through gut microflora in India and abroad.

  15. Specific RNP capture with antisense LNA/DNA mixmers.

    Science.gov (United States)

    Rogell, Birgit; Fischer, Bernd; Rettel, Mandy; Krijgsveld, Jeroen; Castello, Alfredo; Hentze, Matthias W

    2017-08-01

    RNA-binding proteins (RBPs) play essential roles in RNA biology, responding to cellular and environmental stimuli to regulate gene expression. Important advances have helped to determine the (near) complete repertoires of cellular RBPs. However, identification of RBPs associated with specific transcripts remains a challenge. Here, we describe "specific ribonucleoprotein (RNP) capture," a versatile method for the determination of the proteins bound to specific transcripts in vitro and in cellular systems. Specific RNP capture uses UV irradiation to covalently stabilize protein-RNA interactions taking place at "zero distance." Proteins bound to the target RNA are captured by hybridization with antisense locked nucleic acid (LNA)/DNA oligonucleotides covalently coupled to a magnetic resin. After stringent washing, interacting proteins are identified by quantitative mass spectrometry. Applied to in vitro extracts, specific RNP capture identifies the RBPs bound to a reporter mRNA containing the Sex-lethal (Sxl) binding motifs, revealing that the Sxl homolog sister of Sex lethal (Ssx) displays similar binding preferences. This method also revealed the repertoire of RBPs binding to 18S or 28S rRNAs in HeLa cells, including previously unknown rRNA-binding proteins. © 2017 Rogell et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  16. The majority of genes in the pathogenic Neisseria species are present in non-pathogenic Neisseria lactamica, including those designated as 'virulence genes'

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    Saunders Nigel J

    2006-05-01

    Full Text Available Abstract Background Neisseria meningitidis causes the life-threatening diseases meningococcal meningitis and meningococcal septicemia. Neisseria gonorrhoeae is closely related to the meningococcus, but is the cause of the very different infection, gonorrhea. A number of genes have been implicated in the virulence of these related yet distinct pathogens, but the genes that define and differentiate the species and their behaviours have not been established. Further, a related species, Neisseria lactamica is not associated with either type of infection in normally healthy people, and lives as a harmless commensal. We have determined which of the genes so far identified in the genome sequences of the pathogens are also present in this non-pathogenic related species. Results Thirteen unrelated strains of N. lactamica were investigated using comparative genome hybridization to the pan-Neisseria microarray-v2, which contains 2845 unique gene probes. The presence of 127 'virulence genes' was specifically addressed; of these 85 are present in N. lactamica. Of the remaining 42 'virulence genes' only 11 are present in all four of the sequenced pathogenic Neisseria. Conclusion Assessment of the complete dataset revealed that the vast majority of genes present in the pathogens are also present in N. lactamica. Of the 1,473 probes to genes shared by all four pathogenic genome sequences, 1,373 hybridize to N. lactamica. These shared genes cannot include genes that are necessary and sufficient for the virulence of the pathogens, since N. lactamica does not share this behaviour. This provides an essential context for the interpretation of gene complement studies of the pathogens.

  17. A gene catalogue of the euchromatic male-specific region of the horse Y chromosome: comparison with human and other mammals.

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    Nandina Paria

    Full Text Available Studies of the Y chromosome in primates, rodents and carnivores provide compelling evidence that the male specific region of Y (MSY contains functional genes, many of which have specialized roles in spermatogenesis and male-fertility. Little similarity, however, has been found between the gene content and sequence of MSY in different species. This hinders the discovery of species-specific male fertility genes and limits our understanding about MSY evolution in mammals. Here, a detailed MSY gene catalogue was developed for the horse--an odd-toed ungulate. Using direct cDNA selection from horse testis, and sequence analysis of Y-specific BAC clones, 37 horse MSY genes/transcripts were identified. The genes were mapped to the MSY BAC contig map, characterized for copy number, analyzed for transcriptional profiles by RT-PCR, examined for the presence of ORFs, and compared to other mammalian orthologs. We demonstrate that the horse MSY harbors 20 X-degenerate genes with known orthologs in other eutherian species. The remaining 17 genes are acquired or novel and have so far been identified only in the horse or donkey Y chromosomes. Notably, 3 transcripts were found in the heterochromatic part of the Y. We show that despite substantial differences between the sequence, gene content and organization of horse and other mammalian Y chromosomes, the functions of MSY genes are predominantly related to testis and spermatogenesis. Altogether, 10 multicopy genes with testis-specific expression were identified in the horse MSY, and considered likely candidate genes for stallion fertility. The findings establish an important foundation for the study of Y-linked genetic factors governing fertility in stallions, and improve our knowledge about the evolutionary processes that have shaped Y chromosomes in different mammalian lineages.

  18. A gene catalogue of the euchromatic male-specific region of the horse Y chromosome: comparison with human and other mammals.

    Science.gov (United States)

    Paria, Nandina; Raudsepp, Terje; Pearks Wilkerson, Alison J; O'Brien, Patricia C M; Ferguson-Smith, Malcom A; Love, Charles C; Arnold, Carolyn; Rakestraw, Peter; Murphy, William J; Chowdhary, Bhanu P

    2011-01-01

    Studies of the Y chromosome in primates, rodents and carnivores provide compelling evidence that the male specific region of Y (MSY) contains functional genes, many of which have specialized roles in spermatogenesis and male-fertility. Little similarity, however, has been found between the gene content and sequence of MSY in different species. This hinders the discovery of species-specific male fertility genes and limits our understanding about MSY evolution in mammals. Here, a detailed MSY gene catalogue was developed for the horse--an odd-toed ungulate. Using direct cDNA selection from horse testis, and sequence analysis of Y-specific BAC clones, 37 horse MSY genes/transcripts were identified. The genes were mapped to the MSY BAC contig map, characterized for copy number, analyzed for transcriptional profiles by RT-PCR, examined for the presence of ORFs, and compared to other mammalian orthologs. We demonstrate that the horse MSY harbors 20 X-degenerate genes with known orthologs in other eutherian species. The remaining 17 genes are acquired or novel and have so far been identified only in the horse or donkey Y chromosomes. Notably, 3 transcripts were found in the heterochromatic part of the Y. We show that despite substantial differences between the sequence, gene content and organization of horse and other mammalian Y chromosomes, the functions of MSY genes are predominantly related to testis and spermatogenesis. Altogether, 10 multicopy genes with testis-specific expression were identified in the horse MSY, and considered likely candidate genes for stallion fertility. The findings establish an important foundation for the study of Y-linked genetic factors governing fertility in stallions, and improve our knowledge about the evolutionary processes that have shaped Y chromosomes in different mammalian lineages.

  19. Heterogeneous genetic diversity pattern in Plasmodium vivax genes encoding merozoite surface proteins (MSP) -7E, -7F and -7L.

    Science.gov (United States)

    Garzón-Ospina, Diego; Forero-Rodríguez, Johanna; Patarroyo, Manuel A

    2014-12-13

    The msp-7 gene has become differentially expanded in the Plasmodium genus; Plasmodium vivax has the highest copy number of this gene, several of which encode antigenic proteins in merozoites. DNA sequences from thirty-six Colombian clinical isolates from P. vivax (pv) msp-7E, -7F and -7L genes were analysed for characterizing and studying the genetic diversity of these pvmsp-7 members which are expressed during the intra-erythrocyte stage; natural selection signals producing the variation pattern so observed were evaluated. The pvmsp-7E gene was highly polymorphic compared to pvmsp-7F and pvmsp-7L which were seen to have limited genetic diversity; pvmsp-7E polymorphism was seen to have been maintained by different types of positive selection. Even though these copies seemed to be species-specific duplications, a search in the Plasmodium cynomolgi genome (P. vivax sister taxon) showed that both species shared the whole msp-7 repertoire. This led to exploring the long-term effect of natural selection by comparing the orthologous sequences which led to finding signatures for lineage-specific positive selection. The results confirmed that the P. vivax msp-7 family has a heterogeneous genetic diversity pattern; some members are highly conserved whilst others are highly diverse. The results suggested that the 3'-end of these genes encode MSP-7 proteins' functional region whilst the central region of pvmsp-7E has evolved rapidly. The lineage-specific positive selection signals found suggested that mutations occurring in msp-7s genes during host switch may have succeeded in adapting the ancestral P. vivax parasite population to humans.

  20. Rapid bursts of androgen-binding protein (Abp) gene duplication occurred independently in diverse mammals.

    Science.gov (United States)

    Laukaitis, Christina M; Heger, Andreas; Blakley, Tyler D; Munclinger, Pavel; Ponting, Chris P; Karn, Robert C

    2008-02-12

    The draft mouse (Mus musculus) genome sequence revealed an unexpected proliferation of gene duplicates encoding a family of secretoglobin proteins including the androgen-binding protein (ABP) alpha, beta and gamma subunits. Further investigation of 14 alpha-like (Abpa) and 13 beta- or gamma-like (Abpbg) undisrupted gene sequences revealed a rich diversity of developmental stage-, sex- and tissue-specific expression. Despite these studies, our understanding of the evolution of this gene family remains incomplete. Questions arise from imperfections in the initial mouse genome assembly and a dearth of information about the gene family structure in other rodents and mammals. Here, we interrogate the latest 'finished' mouse (Mus musculus) genome sequence assembly to show that the Abp gene repertoire is, in fact, twice as large as reported previously, with 30 Abpa and 34 Abpbg genes and pseudogenes. All of these have arisen since the last common ancestor with rat (Rattus norvegicus). We then demonstrate, by sequencing homologs from species within the Mus genus, that this burst of gene duplication occurred very recently, within the past seven million years. Finally, we survey Abp orthologs in genomes from across the mammalian clade and show that bursts of Abp gene duplications are not specific to the murid rodents; they also occurred recently in the lagomorph (rabbit, Oryctolagus cuniculus) and ruminant (cattle, Bos taurus) lineages, although not in other mammalian taxa. We conclude that Abp genes have undergone repeated bursts of gene duplication and adaptive sequence diversification driven by these genes' participation in chemosensation and/or sexual identification.

  1. Genome specific PPARαB duplicates in salmonids and insights into estrogenic regulation in brown trout.

    Science.gov (United States)

    Madureira, Tânia Vieira; Pinheiro, Ivone; de Paula Freire, Rafaelle; Rocha, Eduardo; Castro, Luis Filipe; Urbatzka, Ralph

    2017-06-01

    Peroxisome proliferator-activated receptors (PPARs) are key regulators of many processes in vertebrates, such as carbohydrate and lipid metabolism. PPARα, a member of the PPAR nuclear receptor gene subfamily (NR1C1), is involved in fatty acid metabolism, namely in peroxisomal β-oxidation. Two gene paralogues, pparαA and pparαB, were described in several teleost species with their origin dating back to the teleost-specific genome duplication (3R). Given the additional salmonid-specific genome duplication (4R), four genes could be theoretically anticipated for this gene subfamily. In this work, we examined the pparα gene repertoire in brown trout, Salmo trutta f. fario. Data disclosed two pparα-like sequences in brown trout. Phylogenetic analyses further revealed that the isolated genes are most likely genome pparαB duplicates, pparαBa and pparαBb, while pparαA is apparently absent in salmonids. Both genes showed a ubiquitous mRNA expression across a panel of 11 different organs. In vitro exposed primary brown trout hepatocytes strongly suggest that pparα gene paralogues are differently regulated by ethinylestradiol (EE2). PparαBb mRNA expression significantly decreased with dosage, reaching significance after exposure to 50μM EE2, while pparαBa mRNA increased, significant at 1μM EE2. The present data enhances the understanding of pparα function and evolution in teleost, and reinforces the evidence of a potential crosstalk between estrogenic and pparα signaling pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Violation of an evolutionarily conserved immunoglobulin diversity gene sequence preference promotes production of dsDNA-specific IgG antibodies.

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    Aaron Silva-Sanchez

    Full Text Available Variability in the developing antibody repertoire is focused on the third complementarity determining region of the H chain (CDR-H3, which lies at the center of the antigen binding site where it often plays a decisive role in antigen binding. The power of VDJ recombination and N nucleotide addition has led to the common conception that the sequence of CDR-H3 is unrestricted in its variability and random in its composition. Under this view, the immune response is solely controlled by somatic positive and negative clonal selection mechanisms that act on individual B cells to promote production of protective antibodies and prevent the production of self-reactive antibodies. This concept of a repertoire of random antigen binding sites is inconsistent with the observation that diversity (DH gene segment sequence content by reading frame (RF is evolutionarily conserved, creating biases in the prevalence and distribution of individual amino acids in CDR-H3. For example, arginine, which is often found in the CDR-H3 of dsDNA binding autoantibodies, is under-represented in the commonly used DH RFs rearranged by deletion, but is a frequent component of rarely used inverted RF1 (iRF1, which is rearranged by inversion. To determine the effect of altering this germline bias in DH gene segment sequence on autoantibody production, we generated mice that by genetic manipulation are forced to utilize an iRF1 sequence encoding two arginines. Over a one year period we collected serial serum samples from these unimmunized, specific pathogen-free mice and found that more than one-fifth of them contained elevated levels of dsDNA-binding IgG, but not IgM; whereas mice with a wild type DH sequence did not. Thus, germline bias against the use of arginine enriched DH sequence helps to reduce the likelihood of producing self-reactive antibodies.

  3. Chloroplast genes as genetic markers for inferring patterns of change, maternal ancestry and phylogenetic relationships among Eleusine species.

    Science.gov (United States)

    Agrawal, Renuka; Agrawal, Nitin; Tandon, Rajesh; Raina, Soom Nath

    2014-01-01

    Assessment of phylogenetic relationships is an important component of any successful crop improvement programme, as wild relatives of the crop species often carry agronomically beneficial traits. Since its domestication in East Africa, Eleusine coracana (2n = 4x = 36), a species belonging to the genus Eleusine (x = 8, 9, 10), has held a prominent place in the semi-arid regions of India, Nepal and Africa. The patterns of variation between the cultivated and wild species reported so far and the interpretations based upon them have been considered primarily in terms of nuclear events. We analysed, for the first time, the phylogenetic relationship between finger millet (E. coracana) and its wild relatives by species-specific chloroplast deoxyribonucleic acid (cpDNA) polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and chloroplast simple sequence repeat (cpSSR) markers/sequences. Restriction fragment length polymorphism of the seven amplified chloroplast genes/intergenic spacers (trnK, psbD, psaA, trnH-trnK, trnL-trnF, 16S and trnS-psbC), nucleotide sequencing of the chloroplast trnK gene and chloroplast microsatellite polymorphism were analysed in all nine known species of Eleusine. The RFLP of all seven amplified chloroplast genes/intergenic spacers and trnK gene sequences in the diploid (2n = 16, 18, 20) and allotetraploid (2n = 36, 38) species resulted in well-resolved phylogenetic trees with high bootstrap values. Eleusine coracana, E. africana, E. tristachya, E. indica and E. kigeziensis did not show even a single change in restriction site. Eleusine intermedia and E. floccifolia were also shown to have identical cpDNA fragment patterns. The cpDNA diversity in Eleusine multiflora was found to be more extensive than that of the other eight species. The trnK gene sequence data complemented the results obtained by PCR-RFLP. The maternal lineage of all three allotetraploid species (AABB, AADD) was the same, with E. indica being the

  4. T Cell Phenotype and T Cell Receptor Repertoire in Patients with Major Depressive Disorder

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    Kostas Patas

    2018-02-01

    Full Text Available While a link between inflammation and the development of neuropsychiatric disorders, including major depressive disorder (MDD is supported by a growing body of evidence, little is known about the contribution of aberrant adaptive immunity in this context. Here, we conducted in-depth characterization of T cell phenotype and T cell receptor (TCR repertoire in MDD. For this cross-sectional case–control study, we recruited antidepressant-free patients with MDD without any somatic or psychiatric comorbidities (n = 20, who were individually matched for sex, age, body mass index, and smoking status to a non-depressed control subject (n = 20. T cell phenotype and repertoire were interrogated using a combination of flow cytometry, gene expression analysis, and next generation sequencing. T cells from MDD patients showed significantly lower surface expression of the chemokine receptors CXCR3 and CCR6, which are known to be central to T cell differentiation and trafficking. In addition, we observed a shift within the CD4+ T cell compartment characterized by a higher frequency of CD4+CD25highCD127low/− cells and higher FOXP3 mRNA expression in purified CD4+ T cells obtained from patients with MDD. Finally, flow cytometry-based TCR Vβ repertoire analysis indicated a less diverse CD4+ T cell repertoire in MDD, which was corroborated by next generation sequencing of the TCR β chain CDR3 region. Overall, these results suggest that T cell phenotype and TCR utilization are skewed on several levels in patients with MDD. Our study identifies putative cellular and molecular signatures of dysregulated adaptive immunity and reinforces the notion that T cells are a pathophysiologically relevant cell population in this disorder.

  5. High Inter-Individual Diversity of Point Mutations, Insertions, and Deletions in Human Influenza Virus Nucleoprotein-Specific Memory B Cells.

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    Sven Reiche

    Full Text Available The diversity of virus-specific antibodies and of B cells among different individuals is unknown. Using single-cell cloning of antibody genes, we generated recombinant human monoclonal antibodies from influenza nucleoprotein-specific memory B cells in four adult humans with and without preceding influenza vaccination. We examined the diversity of the antibody repertoires and found that NP-specific B cells used numerous immunoglobulin genes. The heavy chains (HCs originated from 26 and the kappa light chains (LCs from 19 different germ line genes. Matching HC and LC chains gave rise to 43 genetically distinct antibodies that bound influenza NP. The median lengths of the CDR3 of the HC, kappa and lambda LC were 14, 9 and 11 amino acids, respectively. We identified changes at 13.6% of the amino acid positions in the V gene of the antibody heavy chain, at 8.4% in the kappa and at 10.6 % in the lambda V gene. We identified somatic insertions or deletions in 8.1% of the variable genes. We also found several small groups of clonal relatives that were highly diversified. Our findings demonstrate broadly diverse memory B cell repertoires for the influenza nucleoprotein. We found extensive variation within individuals with a high number of point mutations, insertions, and deletions, and extensive clonal diversification. Thus, structurally conserved proteins can elicit broadly diverse and highly mutated B-cell responses.

  6. Hominoid-specific de novo protein-coding genes originating from long non-coding RNAs.

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    Chen Xie

    2012-09-01

    Full Text Available Tinkering with pre-existing genes has long been known as a major way to create new genes. Recently, however, motherless protein-coding genes have been found to have emerged de novo from ancestral non-coding DNAs. How these genes originated is not well addressed to date. Here we identified 24 hominoid-specific de novo protein-coding genes with precise origination timing in vertebrate phylogeny. Strand-specific RNA-Seq analyses were performed in five rhesus macaque tissues (liver, prefrontal cortex, skeletal muscle, adipose, and testis, which were then integrated with public transcriptome data from human, chimpanzee, and rhesus macaque. On the basis of comparing the RNA expression profiles in the three species, we found that most of the hominoid-specific de novo protein-coding genes encoded polyadenylated non-coding RNAs in rhesus macaque or chimpanzee with a similar transcript structure and correlated tissue expression profile. According to the rule of parsimony, the majority of these hominoid-specific de novo protein-coding genes appear to have acquired a regulated transcript structure and expression profile before acquiring coding potential. Interestingly, although the expression profile was largely correlated, the coding genes in human often showed higher transcriptional abundance than their non-coding counterparts in rhesus macaque. The major findings we report in this manuscript are robust and insensitive to the parameters used in the identification and analysis of de novo genes. Our results suggest that at least a portion of long non-coding RNAs, especially those with active and regulated transcription, may serve as a birth pool for protein-coding genes, which are then further optimized at the transcriptional level.

  7. Architecture and Distribution of Introns in Core Genes of Four Fusarium Species

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    Mmatshepho M. Phasha

    2017-11-01

    Full Text Available Removal of introns from transcribed RNA represents a crucial step during the production of mRNA in eukaryotes. Available whole-genome sequences and expressed sequence tags (ESTs have increased our knowledge of this process and revealed various commonalities among eukaryotes. However, certain aspects of intron structure and diversity are taxon-specific, which can complicate the accuracy of in silico gene prediction methods. Using core genes, we evaluated the distribution and architecture of Fusarium circinatum spliceosomal introns, and linked these characteristics to the accuracy of the predicted gene models of the genome of this fungus. We also evaluated intron distribution and architecture in F. verticillioides, F. oxysporum, and F. graminearum, and made comparisons with F. circinatum. Results indicated that F. circinatum and the three other Fusarium species have canonical 5′ and 3′ splice sites, but with subtle differences that are apparently not shared with those of other fungal genera. The polypyrimidine tract of Fusarium introns was also found to be highly divergent among species and genes. Furthermore, the conserved adenosine nucleoside required during the first step of splicing is contained within unique branch site motifs in certain Fusarium introns. Data generated here show that introns of F. circinatum, as well as F. verticillioides, F. oxysporum, and F. graminearum, are characterized by a number of unique features such as the CTHAH and ACCAT motifs of the branch site. Incorporation of such information into genome annotation software will undoubtedly improve the accuracy of gene prediction methods used for Fusarium species and related fungi.

  8. Comparative analysis of the repertoire of G protein-coupled receptors of three species of the fungal genus Trichoderma.

    Science.gov (United States)

    Gruber, Sabine; Omann, Markus; Zeilinger, Susanne

    2013-05-16

    Eukaryotic organisms employ cell surface receptors such as the seven-transmembrane G protein-coupled receptors (GPCRs) as sensors to connect to the environment. GPCRs react to a variety of extracellular cues and are considered to play central roles in the signal transduction in fungi. Several species of the filamentous ascomycete Trichoderma are potent mycoparasites, i.e. can attack and parasitize other fungi, which turns them into successful bio-fungicides for the protection of plants against fungal phytopathogens. The identification and characterization of GPCRs will provide insights into how Trichoderma communicates with its environment and senses the presence of host fungi. We mined the recently published genomes of the two mycoparasitic biocontrol agents Trichoderma atroviride and Trichoderma virens and compared the identified GPCR-like proteins to those of the saprophyte Trichoderma reesei. Phylogenetic analyses resulted in 14 classes and revealed differences not only among the three Trichoderma species but also between Trichoderma and other fungi. The class comprising proteins of the PAQR family was significantly expanded both in Trichoderma compared to other fungi as well as in the two mycoparasites compared to T. reesei. Expression analysis of the PAQR-encoding genes of the three Trichoderma species revealed that all except one were actually transcribed. Furthermore, the class of receptors with a DUF300 domain was expanded in T. atroviride, and T. virens showed an expansion of PTH11-like receptors compared to T. atroviride and T. reesei. Comparative genome analyses of three Trichoderma species revealed a great diversity of putative GPCRs with genus- and species- specific differences. The expansion of certain classes in the mycoparasites T. atroviride and T. virens is likely to reflect the capability of these fungi to establish various ecological niches and interactions with other organisms such as fungi and plants. These GPCRs consequently represent

  9. Severity of Acute Infectious Mononucleosis Correlates with Cross-Reactive Influenza CD8 T-Cell Receptor Repertoires.

    Science.gov (United States)

    Aslan, Nuray; Watkin, Levi B; Gil, Anna; Mishra, Rabinarayan; Clark, Fransenio G; Welsh, Raymond M; Ghersi, Dario; Luzuriaga, Katherine; Selin, Liisa K

    2017-12-05

    Fifty years after the discovery of Epstein-Barr virus (EBV), it remains unclear how primary infection with this virus leads to massive CD8 T-cell expansion and acute infectious mononucleosis (AIM) in young adults. AIM can vary greatly in severity, from a mild transient influenza-like illness to a prolonged severe syndrome. We questioned whether expansion of a unique HLA-A2.01-restricted, cross-reactive CD8 T-cell response between influenza virus A-M1 58 (IAV-M1) and EBV BMLF1 280 (EBV-BM) could modulate the immune response to EBV and play a role in determining the severity of AIM in 32 college students. Only ex vivo total IAV-M1 and IAV-M1+EBV-BM cross-reactive tetramer + frequencies directly correlated with AIM severity and were predictive of severe disease. Expansion of specific cross-reactive memory IAV-M1 T-cell receptor (TCR) Vβ repertoires correlated with levels of disease severity. There were unique profiles of qualitatively different functional responses in the cross-reactive and EBV-specific CD8 T-cell responses in each of the three groups studied, severe-AIM patients, mild-AIM patients, and seropositive persistently EBV-infected healthy donors, that may result from differences in TCR repertoire use. IAV-M1 tetramer + cells were functionally cross-reactive in short-term cultures, were associated with the highest disease severity in AIM, and displayed enhanced production of gamma interferon, a cytokine that greatly amplifies immune responses, thus frequently contributing to induction of immunopathology. Altogether, these data link heterologous immunity via CD8 T-cell cross-reactivity to CD8 T-cell repertoire selection, function, and resultant disease severity in a common and important human infection. In particular, it highlights for the first time a direct link between the TCR repertoire with pathogenesis and the diversity of outcomes upon pathogen encounter. IMPORTANCE The pathogenic impact of immune responses that by chance cross-react to unrelated

  10. Tamoxifen-elicited uterotrophy: cross-species and cross-ligand analysis of the gene expression program

    Directory of Open Access Journals (Sweden)

    Forgacs Agnes L

    2009-04-01

    Full Text Available Abstract Background Tamoxifen (TAM is a well characterized breast cancer drug and selective estrogen receptor modulator (SERM which also has been associated with a small increase in risk for uterine cancers. TAM's partial agonist activation of estrogen receptor has been characterized for specific gene promoters but not at the genomic level in vivo.Furthermore, reducing uncertainties associated with cross-species extrapolations of pharmaco- and toxicogenomic data remains a formidable challenge. Results A comparative ligand and species analysis approach was conducted to systematically assess the physiological, morphological and uterine gene expression alterations elicited across time by TAM and ethynylestradiol (EE in immature ovariectomized Sprague-Dawley rats and C57BL/6 mice. Differential gene expression was evaluated using custom cDNA microarrays, and the data was compared to identify conserved and divergent responses. 902 genes were differentially regulated in all four studies, 398 of which exhibit identical temporal expression patterns. Conclusion Comparative analysis of EE and TAM differentially expressed gene lists suggest TAM regulates no unique uterine genes that are conserved in the rat and mouse. This demonstrates that the partial agonist activities of TAM extend to molecular targets in regulating only a subset of EE-responsive genes. Ligand-conserved, species-divergent expression of carbonic anhydrase 2 was observed in the microarray data and confirmed by real time PCR. The identification of comparable temporal phenotypic responses linked to related gene expression profiles demonstrates that systematic comparative genomic assessments can elucidate important conserved and divergent mechanisms in rodent estrogen signalling during uterine proliferation.

  11. Patterns of gene flow define species of thermophilic Archaea.

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    Hinsby Cadillo-Quiroz

    2012-02-01

    Full Text Available Despite a growing appreciation of their vast diversity in nature, mechanisms of speciation are poorly understood in Bacteria and Archaea. Here we use high-throughput genome sequencing to identify ongoing speciation in the thermoacidophilic Archaeon Sulfolobus islandicus. Patterns of homologous gene flow among genomes of 12 strains from a single hot spring in Kamchatka, Russia, demonstrate higher levels of gene flow within than between two persistent, coexisting groups, demonstrating that these microorganisms fit the biological species concept. Furthermore, rates of gene flow between two species are decreasing over time in a manner consistent with incipient speciation. Unlike other microorganisms investigated, we do not observe a relationship between genetic divergence and frequency of recombination along a chromosome, or other physical mechanisms that would reduce gene flow between lineages. Each species has its own genetic island encoding unique physiological functions and a unique growth phenotype that may be indicative of ecological specialization. Genetic differentiation between these coexisting groups occurs in large genomic "continents," indicating the topology of genomic divergence during speciation is not uniform and is not associated with a single locus under strong diversifying selection. These data support a model where species do not require physical barriers to gene flow but are maintained by ecological differentiation.

  12. Patterns of gene flow define species of thermophilic Archaea.

    Science.gov (United States)

    Cadillo-Quiroz, Hinsby; Didelot, Xavier; Held, Nicole L; Herrera, Alfa; Darling, Aaron; Reno, Michael L; Krause, David J; Whitaker, Rachel J

    2012-02-01

    Despite a growing appreciation of their vast diversity in nature, mechanisms of speciation are poorly understood in Bacteria and Archaea. Here we use high-throughput genome sequencing to identify ongoing speciation in the thermoacidophilic Archaeon Sulfolobus islandicus. Patterns of homologous gene flow among genomes of 12 strains from a single hot spring in Kamchatka, Russia, demonstrate higher levels of gene flow within than between two persistent, coexisting groups, demonstrating that these microorganisms fit the biological species concept. Furthermore, rates of gene flow between two species are decreasing over time in a manner consistent with incipient speciation. Unlike other microorganisms investigated, we do not observe a relationship between genetic divergence and frequency of recombination along a chromosome, or other physical mechanisms that would reduce gene flow between lineages. Each species has its own genetic island encoding unique physiological functions and a unique growth phenotype that may be indicative of ecological specialization. Genetic differentiation between these coexisting groups occurs in large genomic "continents," indicating the topology of genomic divergence during speciation is not uniform and is not associated with a single locus under strong diversifying selection. These data support a model where species do not require physical barriers to gene flow but are maintained by ecological differentiation.

  13. Misregulation of spermatogenesis genes in Drosophila hybrids is lineage-specific and driven by the combined effects of sterility and fast male regulatory divergence.

    Science.gov (United States)

    Gomes, S; Civetta, A

    2014-09-01

    Hybrid male sterility is a common outcome of crosses between different species. Gene expression studies have found that a number of spermatogenesis genes are differentially expressed in sterile hybrid males, compared with parental species. Late-stage sperm development genes are particularly likely to be misexpressed, with fewer early-stage genes affected. Thus, a link has been posited between misexpression and sterility. A more recent alternative explanation for hybrid gene misexpression has been that it is independent of sterility and driven by divergent evolution of male-specific regulatory elements between species (faster male hypothesis). The faster male hypothesis predicts that misregulation of spermatogenesis genes should be independent of sterility and approximately the same in both hybrids, whereas sterility should only affect gene expression in sterile hybrids. To test the faster male hypothesis vs. the effect of sterility on gene misexpression, we analyse spermatogenesis gene expression in different species pairs of the Drosophila phylogeny, where hybrid male sterility occurs in only one direction of the interspecies cross (i.e. unidirectional sterility). We find significant differences among genes in misexpression with effects that are lineage-specific and caused by sterility or fast male regulatory divergence. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  14. A diverse host thrombospondin-type-1 repeat protein repertoire promotes symbiont colonization during establishment of cnidarian-dinoflagellate symbiosis.

    Science.gov (United States)

    Neubauer, Emilie-Fleur; Poole, Angela Z; Neubauer, Philipp; Detournay, Olivier; Tan, Kenneth; Davy, Simon K; Weis, Virginia M

    2017-05-08

    The mutualistic endosymbiosis between cnidarians and dinoflagellates is mediated by complex inter-partner signaling events, where the host cnidarian innate immune system plays a crucial role in recognition and regulation of symbionts. To date, little is known about the diversity of thrombospondin-type-1 repeat (TSR) domain proteins in basal metazoans or their potential role in regulation of cnidarian-dinoflagellate mutualisms. We reveal a large and diverse repertoire of TSR proteins in seven anthozoan species, and show that in the model sea anemone Aiptasia pallida the TSR domain promotes colonization of the host by the symbiotic dinoflagellate Symbiodinium minutum . Blocking TSR domains led to decreased colonization success, while adding exogenous TSRs resulted in a 'super colonization'. Furthermore, gene expression of TSR proteins was highest at early time-points during symbiosis establishment. Our work characterizes the diversity of cnidarian TSR proteins and provides evidence that these proteins play an important role in the establishment of cnidarian-dinoflagellate symbiosis.

  15. Molecular identification of Nocardia species using the sodA gene: Identificación molecular de especies de Nocardia utilizando el gen sodA.

    Science.gov (United States)

    Sánchez-Herrera, K; Sandoval, H; Mouniee, D; Ramírez-Durán, N; Bergeron, E; Boiron, P; Sánchez-Saucedo, N; Rodríguez-Nava, V

    2017-09-01

    Currently for bacterial identification and classification the rrs gene encoding 16S rRNA is used as a reference method for the analysis of strains of the genus Nocardia. However, it does not have enough polymorphism to differentiate them at the species level. This fact makes it necessary to search for molecular targets that can provide better identification. The sod A gene (encoding the enzyme superoxide dismutase) has had good results in identifying species of other Actinomycetes. In this study the sod A gene is proposed for the identification and differentiation at the species level of the genus Nocardia. We used 41 type species of various collections; a 386 bp fragment of the sod A gene was amplified and sequenced, and a phylogenetic analysis was performed comparing the genes rrs (1171 bp), hsp 65 (401 bp), sec A1 (494 bp), gyr B (1195 bp) and rpo B (401 bp). The sequences were aligned using the Clustal X program. Evolutionary trees according to the neighbour-joining method were created with the programs Phylo_win and MEGA 6. The specific variability of the sod A genus of the genus Nocardia was analysed. A high phylogenetic resolution, significant genetic variability, and specificity and reliability were observed for the differentiation of the isolates at the species level. The polymorphism observed in the sod A gene sequence contains variable regions that allow the discrimination of closely related Nocardia species. The clear specificity, despite its small size, proves to be of great advantage for use in taxonomic studies and clinical diagnosis of the genus Nocardia.

  16. Programming in the Zone: Repertoire Selection for the Large Ensemble

    Science.gov (United States)

    Hopkins, Michael

    2013-01-01

    One of the great challenges ensemble directors face is selecting high-quality repertoire that matches the musical and technical levels of their ensembles. Thoughtful repertoire selection can lead to increased student motivation as well as greater enthusiasm for the music program from parents, administrators, teachers, and community members. Common…

  17. Transcriptome analyses and differential gene expression in a non-model fish species with alternative mating tactics.

    Science.gov (United States)

    Schunter, Celia; Vollmer, Steven V; Macpherson, Enrique; Pascual, Marta

    2014-02-28

    Social dominance is important for the reproductive success of males in many species. In the black-faced blenny (Tripterygion delaisi) during the reproductive season, some males change color and invest in nest making and defending a territory, whereas others do not change color and 'sneak' reproductions when females lay their eggs. Using RNAseq, we profiled differential gene expression between the brains of territorial males, sneaker males, and females to study the molecular signatures of male dimorphism. We found that more genes were differentially expressed between the two male phenotypes than between males and females, suggesting that during the reproductive period phenotypic plasticity is a more important factor in differential gene expression than sexual dimorphism. The territorial male overexpresses genes related to synaptic plasticity and the sneaker male overexpresses genes involved in differentiation and development. Previously suggested candidate genes for social dominance in the context of alternative mating strategies seem to be predominantly species-specific. We present a list of novel genes which are differentially expressed in Tripterygion delaisi. This is the first genome-wide study for a molecular non-model species in the context of alternative mating strategies and provides essential information for further studies investigating the molecular basis of social dominance.

  18. Comparative intra-and inter-specific sexual organ reciprocity in four distylous Primula species in the Himalaya-Hengduan Mountains.

    Science.gov (United States)

    Li, Hai-Dong; Ren, Zong-Xin; Zhou, Wei; Bernhardt, Peter; Zhao, Yan-Hui; Wu, Zhi-Kun; Li, De-Zhu; Wang, Hong

    2018-04-23

    Distyly is a mechanism promoting cross-pollination within a balanced polymorphism. Numerous studies show that the degree of inter-morph sexual organ reciprocity (SOR) within species relates to its pollen-mediated gene flow. Similarly, a lower inter-specific SOR should promote inter-specific isolation when congeners are sympatric, co-blooming, and share pollinators. In this comparative study, we address the significance of SOR at both intra- and inter-specific levels. Seventeen allopatric and eight sympatric populations representing four Primula species (P. anisodora, P. beesiana, P. bulleyana and P. poissonii) native to the Himalaya-Hengduan Mountains were measured for eight floral traits in both long- and short-styled morphs. GLMM and spatial overlap methods were used to compare intra- and inter-specific SOR. While floral morphology differed among four Primula species. SOR within species was generally higher than between species, but species pairs P. poissonii / P. anisodora and P. beesiana / P. bulleyana, the SOR was high at both intra- and inter-specific levels. We didn't detect a significant variation in intra-specific SOR or inter-specific SOR when compare allopatric vs. sympatric populations for all species studied. As intra-specific SOR increased, disassortative mating may be promoted. As inter-specific SOR decreased, inter-specific isolation between co-flowering species pairs also may increase. Hybridization between congeners occurred when inter-specific SOR increased in sympatric populations was confirmed in two species pairs, P. poissonii / P. anisodora and P. beesiana / P. bulleyana. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Functional immunomics: microarray analysis of IgG autoantibody repertoires predicts the future response of mice to induced diabetes.

    Science.gov (United States)

    Quintana, Francisco J; Hagedorn, Peter H; Elizur, Gad; Merbl, Yifat; Domany, Eytan; Cohen, Irun R

    2004-10-05

    One's present repertoire of antibodies encodes the history of one's past immunological experience. Can the present autoantibody repertoire be consulted to predict resistance or susceptibility to the future development of an autoimmune disease? Here, we developed an antigen microarray chip and used bioinformatic analysis to study a model of type 1 diabetes developing in nonobese diabetic male mice in which the disease was accelerated and synchronized by exposing the mice to cyclophosphamide at 4 weeks of age. We obtained sera from 19 individual mice, treated the mice to induce cyclophosphamide-accelerated diabetes (CAD), and found, as expected, that 9 mice became severely diabetic, whereas 10 mice permanently resisted diabetes. We again obtained serum from each mouse after CAD induction. We then analyzed, by using rank-order and superparamagnetic clustering, the patterns of antibodies in individual mice to 266 different antigens spotted on the chip. A selected panel of 27 different antigens (10% of the array) revealed a pattern of IgG antibody reactivity in the pre-CAD sera that discriminated between the mice resistant or susceptible to CAD with 100% sensitivity and 82% specificity (P = 0.017). Surprisingly, the set of IgG antibodies that was informative before CAD induction did not separate the resistant and susceptible groups after the onset of CAD; new antigens became critical for post-CAD repertoire discrimination. Thus, at least for a model disease, present antibody repertoires can predict future disease, predictive and diagnostic repertoires can differ, and decisive information about immune system behavior can be mined by bioinformatic technology. Repertoires matter.

  20. A human-specific de novo protein-coding gene associated with human brain functions.

    Directory of Open Access Journals (Sweden)

    Chuan-Yun Li

    2010-03-01

    Full Text Available To understand whether any human-specific new genes may be associated with human brain functions, we computationally screened the genetic vulnerable factors identified through Genome-Wide Association Studies and linkage analyses of nicotine addiction and found one human-specific de novo protein-coding gene, FLJ33706 (alternative gene symbol C20orf203. Cross-species analysis revealed interesting evolutionary paths of how this gene had originated from noncoding DNA sequences: insertion of repeat elements especially Alu contributed to the formation of the first coding exon and six standard splice junctions on the branch leading to humans and chimpanzees, and two subsequent substitutions in the human lineage escaped two stop codons and created an open reading frame of 194 amino acids. We experimentally verified FLJ33706's mRNA and protein expression in the brain. Real-Time PCR in multiple tissues demonstrated that FLJ33706 was most abundantly expressed in brain. Human polymorphism data suggested that FLJ33706 encodes a protein under purifying selection. A specifically designed antibody detected its protein expression across human cortex, cerebellum and midbrain. Immunohistochemistry study in normal human brain cortex revealed the localization of FLJ33706 protein in neurons. Elevated expressions of FLJ33706 were detected in Alzheimer's brain samples, suggesting the role of this novel gene in human-specific pathogenesis of Alzheimer's disease. FLJ33706 provided the strongest evidence so far that human-specific de novo genes can have protein-coding potential and differential protein expression, and be involved in human brain functions.

  1. Cross-species comparison of biological themes and underlying genes on a global gene expression scale in a mouse model of colorectal liver metastasis and in clinical specimens

    Directory of Open Access Journals (Sweden)

    Schirmacher Peter

    2008-09-01

    Full Text Available Abstract Background Invasion-related genes over-expressed by tumor cells as well as by reacting host cells represent promising drug targets for anti-cancer therapy. Such candidate genes need to be validated in appropriate animal models. Results This study examined the suitability of a murine model (CT26/Balb/C of colorectal liver metastasis to represent clinical liver metastasis specimens using a global gene expression approach. Cross-species similarity was examined between pure liver, liver invasion, tumor invasion and pure tumor compartments through overlap of up-regulated genes and gene ontology (GO-based biological themes on the level of single GO-terms and of condensed GO-term families. Three out of four GO-term families were conserved in a compartment-specific way between the species: secondary metabolism (liver, invasion (invasion front, and immune response (invasion front and liver. Among the individual GO-terms over-represented in the invasion compartments in both species were "extracellular matrix", "cell motility", "cell adhesion" and "antigen presentation" indicating that typical invasion related processes are operating in both species. This was reflected on the single gene level as well, as cross-species overlap of potential target genes over-expressed in the combined invasion front compartments reached up to 36.5%. Generally, histopathology and gene expression correlated well as the highest single gene overlap was found to be 44% in syn-compartmental comparisons (liver versus liver whereas cross-compartmental overlaps were much lower (e.g. liver versus tumor: 9.7%. However, single gene overlap was surprisingly high in some cross-compartmental comparisons (e.g. human liver invasion compartment and murine tumor invasion compartment: 9.0% despite little histolopathologic similarity indicating that invasion relevant genes are not necessarily confined to histologically defined compartments. Conclusion In summary, cross-species

  2. Genome-wide identification and comparative expression analysis reveal a rapid expansion and functional divergence of duplicated genes in the WRKY gene family of cabbage, Brassica oleracea var. capitata.

    Science.gov (United States)

    Yao, Qiu-Yang; Xia, En-Hua; Liu, Fei-Hu; Gao, Li-Zhi

    2015-02-15

    WRKY transcription factors (TFs), one of the ten largest TF families in higher plants, play important roles in regulating plant development and resistance. To date, little is known about the WRKY TF family in Brassica oleracea. Recently, the completed genome sequence of cabbage (B. oleracea var. capitata) allows us to systematically analyze WRKY genes in this species. A total of 148 WRKY genes were characterized and classified into seven subgroups that belong to three major groups. Phylogenetic and synteny analyses revealed that the repertoire of cabbage WRKY genes was derived from a common ancestor shared with Arabidopsis thaliana. The B. oleracea WRKY genes were found to be preferentially retained after the whole-genome triplication (WGT) event in its recent ancestor, suggesting that the WGT event had largely contributed to a rapid expansion of the WRKY gene family in B. oleracea. The analysis of RNA-Seq data from various tissues (i.e., roots, stems, leaves, buds, flowers and siliques) revealed that most of the identified WRKY genes were positively expressed in cabbage, and a large portion of them exhibited patterns of differential and tissue-specific expression, demonstrating that these gene members might play essential roles in plant developmental processes. Comparative analysis of the expression level among duplicated genes showed that gene expression divergence was evidently presented among cabbage WRKY paralogs, indicating functional divergence of these duplicated WRKY genes. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Exploring internal features of 16S rRNA gene for identification of clinically relevant species of the genus Streptococcus

    Science.gov (United States)

    2011-01-01

    Background Streptococcus is an economically important genus as a number of species belonging to this genus are human and animal pathogens. The genus has been divided into different groups based on 16S rRNA gene sequence similarity. The variability observed among the members of these groups is low and it is difficult to distinguish them. The present study was taken up to explore 16S rRNA gene sequence to develop methods that can be used for preliminary identification and can supplement the existing methods for identification of clinically-relevant isolates of the genus Streptococcus. Methods 16S rRNA gene sequences belonging to the isolates of S. dysgalactiae, S. equi, S. pyogenes, S. agalactiae, S. bovis, S. gallolyticus, S. mutans, S. sobrinus, S. mitis, S. pneumoniae, S. thermophilus and S. anginosus were analyzed with the purpose to define genetic variability within each species to generate a phylogenetic framework, to identify species-specific signatures and in-silico restriction enzyme analysis. Results The framework based analysis was used to segregate Streptococcus spp. previously identified upto genus level. This segregation was validated using species-specific signatures and in-silico restriction enzyme analysis. 43 uncharacterized Streptococcus spp. could be identified using this approach. Conclusions The markers generated exploring 16S rRNA gene sequences provided useful tool that can be further used for identification of different species of the genus Streptococcus. PMID:21702978

  4. Development of a gene cloning system in a fast-growing and moderately thermophilic Streptomyces species and heterologous expression of Streptomyces antibiotic biosynthetic gene clusters

    Science.gov (United States)

    2011-01-01

    Background Streptomyces species are a major source of antibiotics. They usually grow slowly at their optimal temperature and fermentation of industrial strains in a large scale often takes a long time, consuming more energy and materials than some other bacterial industrial strains (e.g., E. coli and Bacillus). Most thermophilic Streptomyces species grow fast, but no gene cloning systems have been developed in such strains. Results We report here the isolation of 41 fast-growing (about twice the rate of S. coelicolor), moderately thermophilic (growing at both 30°C and 50°C) Streptomyces strains, detection of one linear and three circular plasmids in them, and sequencing of a 6996-bp plasmid, pTSC1, from one of them. pTSC1-derived pCWH1 could replicate in both thermophilic and mesophilic Streptomyces strains. On the other hand, several Streptomyces replicons function in thermophilic Streptomyces species. By examining ten well-sporulating strains, we found two promising cloning hosts, 2C and 4F. A gene cloning system was established by using the two strains. The actinorhodin and anthramycin biosynthetic gene clusters from mesophilic S. coelicolor A3(2) and thermophilic S. refuineus were heterologously expressed in one of the hosts. Conclusions We have developed a gene cloning and expression system in a fast-growing and moderately thermophilic Streptomyces species. Although just a few plasmids and one antibiotic biosynthetic gene cluster from mesophilic Streptomyces were successfully expressed in thermophilic Streptomyces species, we expect that by utilizing thermophilic Streptomyces-specific promoters, more genes and especially antibiotic genes clusters of mesophilic Streptomyces should be heterologously expressed. PMID:22032628

  5. Cloning of the immunological repertoire in Escherichia coli for generation of monoclonal catalytic antibodies: construction of a heavy chain variable region-specific cDNA library.

    OpenAIRE

    Sastry, L; Alting-Mees, M; Huse, W D; Short, J M; Sorge, J A; Hay, B N; Janda, K D; Benkovic, S J; Lerner, R A

    1989-01-01

    Efficient generation of catalytic antibodies is uniquely dependent on the exact nature of the binding interactions in the antigen-antibody complex. Current methods for generation of monoclonal antibodies do not efficiently survey the immunological repertoire and, therefore, they limit the number of catalysts that can be obtained. We are exploring methods to clone and express the immunological repertoire in Escherichia coli. As the essential first step, we present here a method for the establi...

  6. Multiple independent insertions of 5S rRNA genes in the spliced-leader gene family of trypanosome species.

    Science.gov (United States)

    Beauparlant, Marc A; Drouin, Guy

    2014-02-01

    Analyses of the 5S rRNA genes found in the spliced-leader (SL) gene repeat units of numerous trypanosome species suggest that such linkages were not inherited from a common ancestor, but were the result of independent 5S rRNA gene insertions. In trypanosomes, 5S rRNA genes are found either in the tandemly repeated units coding for SL genes or in independent tandemly repeated units. Given that trypanosome species where 5S rRNA genes are within the tandemly repeated units coding for SL genes are phylogenetically related, one might hypothesize that this arrangement is the result of an ancestral insertion of 5S rRNA genes into the tandemly repeated SL gene family of trypanosomes. Here, we use the types of 5S rRNA genes found associated with SL genes, the flanking regions of the inserted 5S rRNA genes and the position of these insertions to show that most of the 5S rRNA genes found within SL gene repeat units of trypanosome species were not acquired from a common ancestor but are the results of independent insertions. These multiple 5S rRNA genes insertion events in trypanosomes are likely the result of frequent founder events in different hosts and/or geographical locations in species having short generation times.

  7. Identifying the rooted species tree from the distribution of unrooted gene trees under the coalescent.

    Science.gov (United States)

    Allman, Elizabeth S; Degnan, James H; Rhodes, John A

    2011-06-01

    Gene trees are evolutionary trees representing the ancestry of genes sampled from multiple populations. Species trees represent populations of individuals-each with many genes-splitting into new populations or species. The coalescent process, which models ancestry of gene copies within populations, is often used to model the probability distribution of gene trees given a fixed species tree. This multispecies coalescent model provides a framework for phylogeneticists to infer species trees from gene trees using maximum likelihood or Bayesian approaches. Because the coalescent models a branching process over time, all trees are typically assumed to be rooted in this setting. Often, however, gene trees inferred by traditional phylogenetic methods are unrooted. We investigate probabilities of unrooted gene trees under the multispecies coalescent model. We show that when there are four species with one gene sampled per species, the distribution of unrooted gene tree topologies identifies the unrooted species tree topology and some, but not all, information in the species tree edges (branch lengths). The location of the root on the species tree is not identifiable in this situation. However, for 5 or more species with one gene sampled per species, we show that the distribution of unrooted gene tree topologies identifies the rooted species tree topology and all its internal branch lengths. The length of any pendant branch leading to a leaf of the species tree is also identifiable for any species from which more than one gene is sampled.

  8. In situ hybridisation of a large repertoire of muscle-specific transcripts in fish larvae: the new superficial slow-twitch fibres exhibit characteristics of fast-twitch differentiation.

    Science.gov (United States)

    Chauvigné, F; Ralliere, C; Cauty, C; Rescan, P Y

    2006-01-01

    Much of the present information on muscle differentiation in fish concerns the early embryonic stages. To learn more about the maturation and the diversification of the fish myotomal fibres in later stages of ontogeny, we investigated, by means of in situ hybridisation, the developmental expression of a large repertoire of muscle-specific genes in trout larvae from hatching to yolk resorption. At hatching, transcripts for fast and slow muscle protein isoforms, namely myosins, tropomyosins, troponins and myosin binding protein C were present in the deep fast and the superficial slow areas of the myotome, respectively. During myotome expansion that follows hatching, the expression of fast isoforms became progressively confined to the borders of the fast muscle mass, whereas, in contrast, slow muscle isoform transcripts were uniformly expressed in all the slow fibres. Transcripts for several enzymes involved in oxidative metabolism such as citrate synthase, cytochrome oxidase component IV and succinate dehydrogenase, were present throughout the whole myotome of hatching embryos but in later stages became concentrated in slow fibre as well as in lateral fast fibres. Surprisingly, the slow fibres that are added externally to the single superficial layer of the embryonic (original) slow muscle fibres expressed not only slow twitch muscle isoforms but also, transiently, a subset of fast twitch muscle isoforms including MyLC1, MyLC3, MyHC and myosin binding protein C. Taken together these observations show that the growth of the myotome of the fish larvae is associated with complex patterns of muscular gene expression and demonstrate the unexpected presence of fast muscle isoform-expressing fibres in the most superficial part of the slow muscle.

  9. The Caenorhabditis chemoreceptor gene families

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    Robertson Hugh M

    2008-10-01

    Full Text Available Abstract Background Chemoreceptor proteins mediate the first step in the transduction of environmental chemical stimuli, defining the breadth of detection and conferring stimulus specificity. Animal genomes contain families of genes encoding chemoreceptors that mediate taste, olfaction, and pheromone responses. The size and diversity of these families reflect the biology of chemoperception in specific species. Results Based on manual curation and sequence comparisons among putative G-protein-coupled chemoreceptor genes in the nematode Caenorhabditis elegans, we identified approximately 1300 genes and 400 pseudogenes in the 19 largest gene families, most of which fall into larger superfamilies. In the related species C. briggsae and C. remanei, we identified most or all genes in each of the 19 families. For most families, C. elegans has the largest number of genes and C. briggsae the smallest number, suggesting changes in the importance of chemoperception among the species. Protein trees reveal family-specific and species-specific patterns of gene duplication and gene loss. The frequency of strict orthologs varies among the families, from just over 50% in two families to less than 5% in three families. Several families include large species-specific expansions, mostly in C. elegans and C. remanei. Conclusion Chemoreceptor gene families in Caenorhabditis species are large and evolutionarily dynamic as a result of gene duplication and gene loss. These dynamics shape the chemoreceptor gene complements in Caenorhabditis species and define the receptor space available for chemosensory responses. To explain these patterns, we propose the gray pawn hypothesis: individual genes are of little significance, but the aggregate of a large number of diverse genes is required to cover a large phenotype space.

  10. The Caenorhabditis chemoreceptor gene families.

    Science.gov (United States)

    Thomas, James H; Robertson, Hugh M

    2008-10-06

    Chemoreceptor proteins mediate the first step in the transduction of environmental chemical stimuli, defining the breadth of detection and conferring stimulus specificity. Animal genomes contain families of genes encoding chemoreceptors that mediate taste, olfaction, and pheromone responses. The size and diversity of these families reflect the biology of chemoperception in specific species. Based on manual curation and sequence comparisons among putative G-protein-coupled chemoreceptor genes in the nematode Caenorhabditis elegans, we identified approximately 1300 genes and 400 pseudogenes in the 19 largest gene families, most of which fall into larger superfamilies. In the related species C. briggsae and C. remanei, we identified most or all genes in each of the 19 families. For most families, C. elegans has the largest number of genes and C. briggsae the smallest number, suggesting changes in the importance of chemoperception among the species. Protein trees reveal family-specific and species-specific patterns of gene duplication and gene loss. The frequency of strict orthologs varies among the families, from just over 50% in two families to less than 5% in three families. Several families include large species-specific expansions, mostly in C. elegans and C. remanei. Chemoreceptor gene families in Caenorhabditis species are large and evolutionarily dynamic as a result of gene duplication and gene loss. These dynamics shape the chemoreceptor gene complements in Caenorhabditis species and define the receptor space available for chemosensory responses. To explain these patterns, we propose the gray pawn hypothesis: individual genes are of little significance, but the aggregate of a large number of diverse genes is required to cover a large phenotype space.

  11. Evolution and Diversity of Biosynthetic Gene Clusters in Fusarium

    Directory of Open Access Journals (Sweden)

    Koen Hoogendoorn

    2018-06-01

    Full Text Available Plant pathogenic fungi in the Fusarium genus cause severe damage to crops, resulting in great financial losses and health hazards. Specialized metabolites synthesized by these fungi are known to play key roles in the infection process, and to provide survival advantages inside and outside the host. However, systematic studies of the evolution of specialized metabolite-coding potential across Fusarium have been scarce. Here, we apply a combination of bioinformatic approaches to identify biosynthetic gene clusters (BGCs across publicly available genomes from Fusarium, to group them into annotated families and to study gain/loss events of BGC families throughout the history of the genus. Comparison with MIBiG reference BGCs allowed assignment of 29 gene cluster families (GCFs to pathways responsible for the production of known compounds, while for 57 GCFs, the molecular products remain unknown. Comparative analysis of BGC repertoires using ancestral state reconstruction raised several new hypotheses on how BGCs contribute to Fusarium pathogenicity or host specificity, sometimes surprisingly so: for example, a gene cluster for the biosynthesis of hexadehydro-astechrome was identified in the genome of the biocontrol strain Fusarium oxysporum Fo47, while being absent in that of the tomato pathogen F. oxysporum f.sp. lycopersici. Several BGCs were also identified on supernumerary chromosomes; heterologous expression of genes for three terpene synthases encoded on the Fusarium poae supernumerary chromosome and subsequent GC/MS analysis showed that these genes are functional and encode enzymes that each are able to synthesize koraiol; this observed functional redundancy supports the hypothesis that localization of copies of BGCs on supernumerary chromosomes provides freedom for evolutionary innovations to occur, while the original function remains conserved. Altogether, this systematic overview of biosynthetic diversity in Fusarium paves the way for

  12. Species-specific deletion of the viral attachment glycoprotein of avian metapneumovirus.

    Science.gov (United States)

    Kong, Byung-Whi; Foster, Linda K; Foster, Douglas N

    2008-03-01

    The avian metapneumovirus (AMPV) genome encodes the fusion (F), small hydrophobic (SH), and attachment glycoprotein (G) as envelope glycoproteins. The F and G proteins mainly function to allow viral entry into host cells during the early steps of the virus life cycle. The highly variable AMPV G protein is a major determinant for distinguishing virus subtypes. Sequence analysis was used to determine if any differences between avian or mammalian cell propagated subtype C AMPV could be detected for the 1.8kb G gene. As a result, the complete 1.8kb G gene was found to be present when AMPV was propagated in our immortal turkey turbinate (TT-1) cell line regardless of passage number. Surprisingly, AMPV propagated for 15 or more passages in mammalian Vero cells revealed an essentially deleted G gene in the viral genome, resulting in no G gene mRNA expression. Although the Vero cell propagated AMPV genome contained a small 122 nucleotide fragment of the G gene, no other mRNA variants were detected from either mammalian or avian propagated AMPV. The G gene truncation might be caused by cellular molecular mechanisms that are species-specific. The lack of viral gene deletions suggests that avian cell propagated AMPV will provide a better alternative host for live recombinant vaccine development based on a reverse genetics system.

  13. Personal receptor repertoires: olfaction as a model

    Directory of Open Access Journals (Sweden)

    Olender Tsviya

    2012-08-01

    Full Text Available Abstract Background Information on nucleotide diversity along completely sequenced human genomes has increased tremendously over the last few years. This makes it possible to reassess the diversity status of distinct receptor proteins in different human individuals. To this end, we focused on the complete inventory of human olfactory receptor coding regions as a model for personal receptor repertoires. Results By performing data-mining from public and private sources we scored genetic variations in 413 intact OR loci, for which one or more individuals had an intact open reading frame. Using 1000 Genomes Project haplotypes, we identified a total of 4069 full-length polypeptide variants encoded by these OR loci, average of ~10 per locus, constituting a lower limit for the effective human OR repertoire. Each individual is found to harbor as many as 600 OR allelic variants, ~50% higher than the locus count. Because OR neuronal expression is allelically excluded, this has direct effect on smell perception diversity of the species. We further identified 244 OR segregating pseudogenes (SPGs, loci showing both intact and pseudogene forms in the population, twenty-six of which are annotatively “resurrected” from a pseudogene status in the reference genome. Using a custom SNP microarray we validated 150 SPGs in a cohort of 468 individuals, with every individual genome averaging 36 disrupted sequence variations, 15 in homozygote form. Finally, we generated a multi-source compendium of 63 OR loci harboring deletion Copy Number Variations (CNVs. Our combined data suggest that 271 of the 413 intact OR loci (66% are affected by nonfunctional SNPs/indels and/or CNVs. Conclusions These results portray a case of unusually high genetic diversity, and suggest that individual humans have a highly personalized inventory of functional olfactory receptors, a conclusion that might apply to other receptor multigene families.

  14. Evolution of the complementary sex-determination gene of honey bees: balancing selection and trans-species polymorphisms.

    Science.gov (United States)

    Cho, Soochin; Huang, Zachary Y; Green, Daniel R; Smith, Deborah R; Zhang, Jianzhi

    2006-11-01

    The mechanism of sex determination varies substantively among evolutionary lineages. One important mode of genetic sex determination is haplodiploidy, which is used by approximately 20% of all animal species, including >200,000 species of the entire insect order Hymenoptera. In the honey bee Apis mellifera, a hymenopteran model organism, females are heterozygous at the csd (complementary sex determination) locus, whereas males are hemizygous (from unfertilized eggs). Fertilized homozygotes develop into sterile males that are eaten before maturity. Because homozygotes have zero fitness and because common alleles are more likely than rare ones to form homozygotes, csd should be subject to strong overdominant selection and negative frequency-dependent selection. Under these selective forces, together known as balancing selection, csd is expected to exhibit a high degree of intraspecific polymorphism, with long-lived alleles that may be even older than the species. Here we sequence the csd genes as well as randomly selected neutral genomic regions from individuals of three closely related species, A. mellifera, Apis cerana, and Apis dorsata. The polymorphic level is approximately seven times higher in csd than in the neutral regions. Gene genealogies reveal trans-species polymorphisms at csd but not at any neutral regions. Consistent with the prediction of rare-allele advantage, nonsynonymous mutations are found to be positively selected in csd only in early stages after their appearances. Surprisingly, three different hypervariable repetitive regions in csd are present in the three species, suggesting variable mechanisms underlying allelic specificities. Our results provide a definitive demonstration of balancing selection acting at the honey bee csd gene, offer insights into the molecular determinants of csd allelic specificities, and help avoid homozygosity in bee breeding.

  15. [Development of specific and degenerated primers to CesA genes encoding flax (Linum usitatissimum L.) cellulose synthase].

    Science.gov (United States)

    Grushetskaia, Z E; Lemesh, V A; Khotyleva, L V

    2010-01-01

    Cellulose synthase catalytic subunit genes, CesA, have been discovered in several higher plant species, and it has been shown that the CesA gene family has multiple members. HVR2 fragment of these genes determine the class specificity of the CESA protein and its participation in the primary or secondary cell wall synthesis. The aim of this study was development of specific and degenerated primers to flax CesA gene fragments leading to obtaining the class specific HVR2 region of the gene. Two pairs of specific primers to the certain fragments of CesA-1 and CesA-6 genes and one pair of degenerated primers to HVR2 region of all flax CesA genes were developed basing on comparison of six CesA EST sequences of flax and full cDNA sequences of Arabidopsis, poplar, maize and cotton plants, obtained from GenBank. After amplification of flax cDNA, the bands of expected size were detected (201 and 300 b.p. for the CesA-1 and CesA-6, and 600 b.p. for the HVR2 region of CesA respectively). The developed markers can be used for cloning and sequencing of flax CesA genes, identifying their number in flax genome, tissue and stage specificity.

  16. Using a periclinal chimera to unravel layer-specific gene expression in plants.

    Science.gov (United States)

    Filippis, Ioannis; Lopez-Cobollo, Rosa; Abbott, James; Butcher, Sarah; Bishop, Gerard J

    2013-09-01

    Plant organs are made from multiple cell types, and defining the expression level of a gene in any one cell or group of cells from a complex mixture is difficult. Dicotyledonous plants normally have three distinct layers of cells, L1, L2 and L3. Layer L1 is the single layer of cells making up the epidermis, layer L2 the single cell sub-epidermal layer and layer L3 constitutes the rest of the internal cells. Here we show how it is possible to harvest an organ and characterise the level of layer-specific expression by using a periclinal chimera that has its L1 layer from Solanum pennellii and its L2 and L3 layers from Solanum lycopersicum. This is possible by measuring the level of the frequency of species-specific transcripts. RNA-seq analysis enabled the genome-wide assessment of whether a gene is expressed in the L1 or L2/L3 layers. From 13 277 genes that are expressed in both the chimera and the parental lines and with at least one polymorphism between the parental alleles, we identified 382 genes that are preferentially expressed in L1 in contrast to 1159 genes in L2/L3. Gene ontology analysis shows that many genes preferentially expressed in L1 are involved in cutin and wax biosynthesis, whereas numerous genes that are preferentially expressed in L2/L3 tissue are associated with chloroplastic processes. These data indicate the use of such chimeras and provide detailed information on the level of layer-specific expression of genes. © 2013 East Malling Research The Plant Journal © 2013 John Wiley & Sons Ltd.

  17. Detecting lineage-specific adaptive evolution of brain-expressed genes in human using rhesus macaque as outgroup

    DEFF Research Database (Denmark)

    Yu, Xiao-Jing; Zheng, Hong-Kun; Wang, Jun

    2006-01-01

    related species as outgroup, it is difficult to identify human-lineage-specific changes, which is critical in delineating the biological uniqueness of humans. In this study, we conducted phylogeny-based analyses of 2633 human brain-expressed genes using rhesus macaque as the outgroup. We identified 47...... candidate genes showing strong evidence of positive selection in the human lineage. Genes with maximal expression in the brain showed a higher evolutionary rate in human than in chimpanzee. We observed that many immune-defense-related genes were under strong positive selection, and this trend was more...

  18. Sexual repertoires of heterosexuals: implications for HIV/sexually transmitted disease risk and prevention. The ACSF Group, Analyse des Comportements Sexuels en France.

    Science.gov (United States)

    Messiah, A; Blin, P; Fiche, V

    1995-12-01

    To provide a quantitative and population-based analysis of sexual repertoires among heterosexuals. The French National Survey of Sexual Behaviour (ACSF), conducted between September 1991 and February 1992 on a representative sample of the population aged 18-69 years. Sexual practices of the last heterosexual encounter were investigated among 4261 individuals; we measured the combinations of different practices and their correlations with age, and calculated frequencies for the main repertoires and their correlations with the interpartner relationship. Vaginal penetration and caressing were almost systematic, self-masturbation and anal penetration were rare, while mutual masturbation and orogenital practices had intermediate levels of occurrence. Examination of the correlations revealed (1) a very high correlation between practices which are reciprocal or symmetrical, (2) a strong association between genito-manual and genito-oral practices, (3) an association between anal penetration and fellatio, and (4) no clear correlation between any set of practices and vaginal sex or condom use. A small number of repertoires accounted for the vast majority of encounters. Younger people tended to have a more diversified repertoire. Repertoire types and diversity were strongly correlated to the pattern of interpartner relationship, independently of age. Reciprocity seems a standard feature of the heterosexual repertoire. The absence of a negative correlation between vaginal or anal penetration and other practices argues against promotion of the latter as substitute for the former. By contrast, the independence between condom use and any specific repertoire argues for its promotion as a universal means of protection.

  19. Specific Gene Loci of Clinical Pseudomonas putida Isolates.

    Directory of Open Access Journals (Sweden)

    Lázaro Molina

    Full Text Available Pseudomonas putida are ubiquitous inhabitants of soils and clinical isolates of this species have been seldom described. Clinical isolates show significant variability in their ability to cause damage to hosts because some of them are able to modulate the host's immune response. In the current study, comparisons between the genomes of different clinical and environmental strains of P. putida were done to identify genetic clusters shared by clinical isolates that are not present in environmental isolates. We show that in clinical strains specific genes are mostly present on transposons, and that this set of genes exhibit high identity with genes found in pathogens and opportunistic pathogens. The set of genes prevalent in P. putida clinical isolates, and absent in environmental isolates, are related with survival under oxidative stress conditions, resistance against biocides, amino acid metabolism and toxin/antitoxin (TA systems. This set of functions have influence in colonization and survival within human tissues, since they avoid host immune response or enhance stress resistance. An in depth bioinformatic analysis was also carried out to identify genetic clusters that are exclusive to each of the clinical isolates and that correlate with phenotypical differences between them, a secretion system type III-like was found in one of these clinical strains, a determinant of pathogenicity in Gram-negative bacteria.

  20. Mammalian transcriptional hotspots are enriched for tissue specific enhancers near cell type specific highly expressed genes and are predicted to act as transcriptional activator hubs.

    Science.gov (United States)

    Joshi, Anagha

    2014-12-30

    Transcriptional hotspots are defined as genomic regions bound by multiple factors. They have been identified recently as cell type specific enhancers regulating developmentally essential genes in many species such as worm, fly and humans. The in-depth analysis of hotspots across multiple cell types in same species still remains to be explored and can bring new biological insights. We therefore collected 108 transcription-related factor (TF) ChIP sequencing data sets in ten murine cell types and classified the peaks in each cell type in three groups according to binding occupancy as singletons (low-occupancy), combinatorials (mid-occupancy) and hotspots (high-occupancy). The peaks in the three groups clustered largely according to the occupancy, suggesting priming of genomic loci for mid occupancy irrespective of cell type. We then characterized hotspots for diverse structural functional properties. The genes neighbouring hotspots had a small overlap with hotspot genes in other cell types and were highly enriched for cell type specific function. Hotspots were enriched for sequence motifs of key TFs in that cell type and more than 90% of hotspots were occupied by pioneering factors. Though we did not find any sequence signature in the three groups, the H3K4me1 binding profile had bimodal peaks at hotspots, distinguishing hotspots from mono-modal H3K4me1 singletons. In ES cells, differentially expressed genes after perturbation of activators were enriched for hotspot genes suggesting hotspots primarily act as transcriptional activator hubs. Finally, we proposed that ES hotspots might be under control of SetDB1 and not DNMT for silencing. Transcriptional hotspots are enriched for tissue specific enhancers near cell type specific highly expressed genes. In ES cells, they are predicted to act as transcriptional activator hubs and might be under SetDB1 control for silencing.

  1. Self assertion modeled as a network repertoire of multi-determinant antibodies

    NARCIS (Netherlands)

    Takumi, K.; Boer, R.J. de

    1996-01-01

    We study repertoire selection in a network of natural antibodies that is maintained by stimulatory idiotypic interactions. The natural antibody repertoire develops in an environment of self epitopes to which the self-reactive B cell clones are completely tolerant. For the modeling formalism, we

  2. The Use of Cytochrome b Gene as a Specific Marker of the Rat Meat (Rattus norvegicus on Meat and Meat Products

    Directory of Open Access Journals (Sweden)

    C. Sumantri

    2012-04-01

    Full Text Available Falsification of the origin of livestock meat and its processed with rat meat is a problem that must be overcome to ensure food safety. One way that is often used to detect forgeries by using cytochrome b gene as a marker. The purpose of this study was to create a specific primer derived from cytochrome b sequences in rat (Rattus norvegicus as the DNA marker to detect any contamination of rat meat on fresh livestock meat and its processed meat products. Meatballs were made from beef meat with the addition of rat 1%-25%, and the meatballs were obtained from traditional markets. DNA extraction was conducted from seven species (goat, chicken, cattle, sheep, pig, horse, and rat by using phenol-chloroform. The highest success rate in detecting the presence of rat meat in a mixture of beef meatballs at concentration of 15% was 100%. The specific fragment of cytochrome b gene in R. norvegicus has no similarity with the cytochrome b gene from six other species, so it can be used as molecular markers to detect the presence of rat meat contamination in the processed of meat products. Amplified fragment length for goats, chickens, cattle, sheep, pigs, horses, and rats 157, 227, 274, 331, 398, 439 and 603 bp respectively. The amplification of cytochrome b gene in seven species of animals with different fragment length indicated the specificity of cytochrome b gene sequences among species.

  3. Metagenomic species profiling using universal phylogenetic marker genes

    DEFF Research Database (Denmark)

    Sunagawa, Shinichi; Mende, Daniel R; Zeller, Georg

    2013-01-01

    To quantify known and unknown microorganisms at species-level resolution using shotgun sequencing data, we developed a method that establishes metagenomic operational taxonomic units (mOTUs) based on single-copy phylogenetic marker genes. Applied to 252 human fecal samples, the method revealed th...... that on average 43% of the species abundance and 58% of the richness cannot be captured by current reference genome-based methods. An implementation of the method is available at http://www.bork.embl.de/software/mOTU/.......To quantify known and unknown microorganisms at species-level resolution using shotgun sequencing data, we developed a method that establishes metagenomic operational taxonomic units (mOTUs) based on single-copy phylogenetic marker genes. Applied to 252 human fecal samples, the method revealed...

  4. [High gene conversion frequency between genes encoding 2-deoxyglucose-6-phosphate phosphatase in 3 Saccharomyces species].

    Science.gov (United States)

    Piscopo, Sara-Pier; Drouin, Guy

    2014-05-01

    Gene conversions are nonreciprocal sequence exchanges between genes. They are relatively common in Saccharomyces cerevisiae, but few studies have investigated the evolutionary fate of gene conversions or their functional impacts. Here, we analyze the evolution and impact of gene conversions between the two genes encoding 2-deoxyglucose-6-phosphate phosphatase in S. cerevisiae, Saccharomyces paradoxus and Saccharomyces mikatae. Our results demonstrate that the last half of these genes are subject to gene conversions among these three species. The greater similarity and the greater percentage of GC nucleotides in the converted regions, as well as the absence of long regions of adjacent common converted sites, suggest that these gene conversions are frequent and occur independently in all three species. The high frequency of these conversions probably result from the fact that they have little impact on the protein sequences encoded by these genes.

  5. Development of a multiplex assay for genus- and species-specific detection of Phytophthora based on differences in mitochondrial gene order

    Science.gov (United States)

    G. J. Bilodeau; F. N. Martin; M. D. Coffey; C. L. Blomquist

    2014-01-01

    A molecular diagnostic assay for Phytophthora spp. that is specific, sensitive, has both genus- and species-specific detection capabilities multiplexed, and can be used to systematically develop markers for detection of a wide range of species would facilitate research and regulatory efforts. To address this need, a marker system was developed...

  6. Integrative characterization of germ cell-specific genes from mouse spermatocyte UniGene library

    Directory of Open Access Journals (Sweden)

    Eddy Edward M

    2007-07-01

    Full Text Available Abstract Background The primary regulator of spermatogenesis, a highly ordered and tightly regulated developmental process, is an intrinsic genetic program involving male germ cell-specific genes. Results We analyzed the mouse spermatocyte UniGene library containing 2155 gene-oriented transcript clusters. We predict that 11% of these genes are testis-specific and systematically identified 24 authentic genes specifically and abundantly expressed in the testis via in silico and in vitro approaches. Northern blot analysis disclosed various transcript characteristics, such as expression level, size and the presence of isoform. Expression analysis revealed developmentally regulated and stage-specific expression patterns in all of the genes. We further analyzed the genes at the protein and cellular levels. Transfection assays performed using GC-2 cells provided information on the cellular characteristics of the gene products. In addition, antibodies were generated against proteins encoded by some of the genes to facilitate their identification and characterization in spermatogenic cells and sperm. Our data suggest that a number of the gene products are implicated in transcriptional regulation, nuclear integrity, sperm structure and motility, and fertilization. In particular, we found for the first time that Mm.333010, predicted to contain a trypsin-like serine protease domain, is a sperm acrosomal protein. Conclusion We identify 24 authentic genes with spermatogenic cell-specific expression, and provide comprehensive information about the genes. Our findings establish a new basis for future investigation into molecular mechanisms underlying male reproduction.

  7. Utility of Multi-Gene Loci for Forensic Species Diagnosis of Blowflies

    Science.gov (United States)

    Zaidi, Farrah; Wei, Shu-jun; Shi, Min; Chen, Xue-xin

    2011-01-01

    Contemporary studies in forensic entomology exhaustively evaluate gene sequences because these constitute the fastest and most accurate method of species identification. For this purpose single gene segments, cytochrome oxidase subunit I (COI) in particular, are commonly used. However, the limitation of such sequences in identification, especially of closely related species and populations, demand a multi-gene approach. But this raises the question of which group of genes can best fulfill the identification task? In this context the utility of five gene segments was explored among blowfly species from two distinct geographic regions, China and Pakistan. COI, cytochrome b (CYTB), NADH dehydrogenase 5 (ND5), nuclear internal transcribed spacers (ITS1 and ITS2), were sequenced for eight blowfly species including Chrysomya megacephala F. (Diptera: Calliphoidae), Ch. pinguis Walker, Lucilia sericata Meigen L. porphyrina Walker, L. illustris Meigen Hemipyrellia ligurriens Wiedemann, Aldrichina grahami Aldrich, and the housefly, Musca domestica L. (Muscidae), from Hangzhou, China; while COI, CYTB, and ITS2 were sequenced for four species, i.e. Ch. megacephala, Ch. rufifacies, L. cuprina, and the flesh fly, Sarcophaga albiceps Meigen (Sarcophagidae), from Dera Ismail Khan Pakistan. The results demonstrate a universal utility of these gene segments in the molecular identification of flies of forensic importance. PMID:21864153

  8. The Drosophila Translational Control Element (TCE is required for high-level transcription of many genes that are specifically expressed in testes.

    Directory of Open Access Journals (Sweden)

    Rebeccah J Katzenberger

    Full Text Available To investigate the importance of core promoter elements for tissue-specific transcription of RNA polymerase II genes, we examined testis-specific transcription in Drosophila melanogaster. Bioinformatic analyses of core promoter sequences from 190 genes that are specifically expressed in testes identified a 10 bp A/T-rich motif that is identical to the translational control element (TCE. The TCE functions in the 5' untranslated region of Mst(3CGP mRNAs to repress translation, and it also functions in a heterologous gene to regulate transcription. We found that among genes with focused initiation patterns, the TCE is significantly enriched in core promoters of genes that are specifically expressed in testes but not in core promoters of genes that are specifically expressed in other tissues. The TCE is variably located in core promoters and is conserved in melanogaster subgroup species, but conservation dramatically drops in more distant species. In transgenic flies, short (300-400 bp genomic regions containing a TCE directed testis-specific transcription of a reporter gene. Mutation of the TCE significantly reduced but did not abolish reporter gene transcription indicating that the TCE is important but not essential for transcription activation. Finally, mutation of testis-specific TFIID (tTFIID subunits significantly reduced the transcription of a subset of endogenous TCE-containing but not TCE-lacking genes, suggesting that tTFIID activity is limited to TCE-containing genes but that tTFIID is not an obligatory regulator of TCE-containing genes. Thus, the TCE is a core promoter element in a subset of genes that are specifically expressed in testes. Furthermore, the TCE regulates transcription in the context of short genomic regions, from variable locations in the core promoter, and both dependently and independently of tTFIID. These findings set the stage for determining the mechanism by which the TCE regulates testis-specific transcription and

  9. The Drosophila Translational Control Element (TCE) is required for high-level transcription of many genes that are specifically expressed in testes.

    Science.gov (United States)

    Katzenberger, Rebeccah J; Rach, Elizabeth A; Anderson, Ashley K; Ohler, Uwe; Wassarman, David A

    2012-01-01

    To investigate the importance of core promoter elements for tissue-specific transcription of RNA polymerase II genes, we examined testis-specific transcription in Drosophila melanogaster. Bioinformatic analyses of core promoter sequences from 190 genes that are specifically expressed in testes identified a 10 bp A/T-rich motif that is identical to the translational control element (TCE). The TCE functions in the 5' untranslated region of Mst(3)CGP mRNAs to repress translation, and it also functions in a heterologous gene to regulate transcription. We found that among genes with focused initiation patterns, the TCE is significantly enriched in core promoters of genes that are specifically expressed in testes but not in core promoters of genes that are specifically expressed in other tissues. The TCE is variably located in core promoters and is conserved in melanogaster subgroup species, but conservation dramatically drops in more distant species. In transgenic flies, short (300-400 bp) genomic regions containing a TCE directed testis-specific transcription of a reporter gene. Mutation of the TCE significantly reduced but did not abolish reporter gene transcription indicating that the TCE is important but not essential for transcription activation. Finally, mutation of testis-specific TFIID (tTFIID) subunits significantly reduced the transcription of a subset of endogenous TCE-containing but not TCE-lacking genes, suggesting that tTFIID activity is limited to TCE-containing genes but that tTFIID is not an obligatory regulator of TCE-containing genes. Thus, the TCE is a core promoter element in a subset of genes that are specifically expressed in testes. Furthermore, the TCE regulates transcription in the context of short genomic regions, from variable locations in the core promoter, and both dependently and independently of tTFIID. These findings set the stage for determining the mechanism by which the TCE regulates testis-specific transcription and understanding the

  10. Developing Professional “Game Teacher” Repertoires

    DEFF Research Database (Denmark)

    Lieberoth, Andreas; Hanghøj, Thorkild

    2017-01-01

    for in their professional careers. We expand and explain these findings using embedded mixed methods analysis, and conclude that games are a good practical case for training various teaching competences, but that building flexible professional repertoires requires more varied experiences than a single course can muster.......The first Danish Game-Based Learning course offered by a teachers college enrolled 42 students with a variety of backgrounds and interests in games. We characterize the students who enrolled in the course in terms of gaming literacies and preferences, and gauge the impact of the course in terms...... of building actionable skill sets. Following Schön (1986) we use these data to frame students’ transition from gamers or game curious teachers to developing professional repertoires.Interviews and statistical comparison to other students indicate that while student’s existing preferences for the “heavier...

  11. Nod Factor Effects on Root Hair-Specific Transcriptome of Medicago truncatula: Focus on Plasma Membrane Transport Systems and Reactive Oxygen Species Networks.

    Science.gov (United States)

    Damiani, Isabelle; Drain, Alice; Guichard, Marjorie; Balzergue, Sandrine; Boscari, Alexandre; Boyer, Jean-Christophe; Brunaud, Véronique; Cottaz, Sylvain; Rancurel, Corinne; Da Rocha, Martine; Fizames, Cécile; Fort, Sébastien; Gaillard, Isabelle; Maillol, Vincent; Danchin, Etienne G J; Rouached, Hatem; Samain, Eric; Su, Yan-Hua; Thouin, Julien; Touraine, Bruno; Puppo, Alain; Frachisse, Jean-Marie; Pauly, Nicolas; Sentenac, Hervé

    2016-01-01

    Root hairs are involved in water and nutrient uptake, and thereby in plant autotrophy. In legumes, they also play a crucial role in establishment of rhizobial symbiosis. To obtain a holistic view of Medicago truncatula genes expressed in root hairs and of their regulation during the first hours of the engagement in rhizobial symbiotic interaction, a high throughput RNA sequencing on isolated root hairs from roots challenged or not with lipochitooligosaccharides Nod factors (NF) for 4 or 20 h was carried out. This provided a repertoire of genes displaying expression in root hairs, responding or not to NF, and specific or not to legumes. In analyzing the transcriptome dataset, special attention was paid to pumps, transporters, or channels active at the plasma membrane, to other proteins likely to play a role in nutrient ion uptake, NF electrical and calcium signaling, control of the redox status or the dynamic reprogramming of root hair transcriptome induced by NF treatment, and to the identification of papilionoid legume-specific genes expressed in root hairs. About 10% of the root hair expressed genes were significantly up- or down-regulated by NF treatment, suggesting their involvement in remodeling plant functions to allow establishment of the symbiotic relationship. For instance, NF-induced changes in expression of genes encoding plasma membrane transport systems or disease response proteins indicate that root hairs reduce their involvement in nutrient ion absorption and adapt their immune system in order to engage in the symbiotic interaction. It also appears that the redox status of root hair cells is tuned in response to NF perception. In addition, 1176 genes that could be considered as "papilionoid legume-specific" were identified in the M. truncatula root hair transcriptome, from which 141 were found to possess an ortholog in every of the six legume genomes that we considered, suggesting their involvement in essential functions specific to legumes. This

  12. Nod factor effects on root hair-specific transcriptome of Medicago truncatula: focus on plasma membrane transport systems and reactive oxygen species networks

    Directory of Open Access Journals (Sweden)

    Isabelle eDAMIANI

    2016-06-01

    Full Text Available Root hairs are involved in water and nutrient uptake, and thereby in plant autotrophy. In legumes, they also play a crucial role in establishment of rhizobial symbiosis. To obtain a holistic view of Medicago truncatula genes expressed in root hairs and of their regulation during the first hours of the engagement in rhizobial symbiotic interaction, a high throughput RNA sequencing on isolated root hairs from roots challenged or not with lipochitooligosaccharides Nod factors (NF for 4 h or 20 h was carried out. This provided a repertoire of genes displaying expression in root hairs, responding or not to NF and specific or not to legumes. In analyzing the transcriptome dataset, special attention was paid to pumps, transporters or channels active at the plasma membrane, to other proteins likely to play a role in nutrient ion uptake, NF electrical and calcium signaling, control of the redox status or the dynamic reprogramming of root hair transcriptome induced by NF treatment, and to the identification of papilionoid legume-specific genes expressed in root hairs. About 10 percent of the root hair expressed genes were significantly up- or down-regulated by NF treatment, suggesting their involvement in remodeling plant functions to allow establishment of the symbiotic relationship. For instance, NF-induced changes in expression of genes encoding plasma membrane transport systems or disease response proteins indicate that root hairs reduce their involvement in nutrient ion absorption and adapt their immune system in order to engage in the symbiotic interaction. It also appears that the redox status of root hair cells is tuned in response to NF perception. In addition, 1,176 genes that could be considered as papilionoid legume-specific were identified in the M. truncatula root hair transcriptome, from which 141 were found to possess an orthologue in every of the 6 legume genomes that we considered, suggesting their involvement in essential functions

  13. Social complexity parallels vocal complexity: a comparison of three non-human primate species.

    Science.gov (United States)

    Bouchet, Hélène; Blois-Heulin, Catherine; Lemasson, Alban

    2013-01-01

    Social factors play a key role in the structuring of vocal repertoires at the individual level, notably in non-human primates. Some authors suggested that, at the species level too, social life may have driven the evolution of communicative complexity, but this has rarely been empirically tested. Here, we use a comparative approach to address this issue. We investigated vocal variability, at both the call type and the repertoire levels, in three forest-dwelling species of Cercopithecinae presenting striking differences in their social systems, in terms of social organization as well as social structure. We collected female call recordings from twelve De Brazza's monkeys (Cercopithecus neglectus), six Campbell's monkeys (Cercopithecus campbelli) and seven red-capped mangabeys (Cercocebus torquatus) housed in similar conditions. First, we noted that the level of acoustic variability and individual distinctiveness found in several call types was related to their importance in social functioning. Contact calls, essential to intra-group cohesion, were the most individually distinctive regardless of the species, while threat calls were more structurally variable in mangabeys, the most "despotic" of our three species. Second, we found a parallel between the degree of complexity of the species' social structure and the size, diversity, and usage of its vocal repertoire. Mangabeys (most complex social structure) called twice as often as guenons and displayed the largest and most complex repertoire. De Brazza's monkeys (simplest social structure) displayed the smallest and simplest repertoire. Campbell's monkeys displayed an intermediate pattern. Providing evidence of higher levels of vocal variability in species presenting a more complex social system, our results are in line with the theory of a social-vocal coevolution of communicative abilities, opening new perspectives for comparative research on the evolution of communication systems in different animal taxa.

  14. Quantitative Analysis of Repertoire Scale Immunoglobulin properties in Vaccine Induced B cell Responses

    Science.gov (United States)

    Immunosequencing now readily generates 103105 sequences per sample ; however, statistical analysis of these repertoires is challenging because of the high genetic...diversity of BCRs and the elaborate clonal relationships among them. To date, most immunosequencing analyses have focused on reporting qualitative ...repertoire differences, (2) identifying how two repertoires differ, and (3) determining appropriate confidence intervals for assessing the size of the differences and their potential biological relevance.

  15. Comparative analysis of the repertoire of G protein-coupled receptors of three species of the fungal genus Trichoderma

    Science.gov (United States)

    2013-01-01

    Background Eukaryotic organisms employ cell surface receptors such as the seven-transmembrane G protein-coupled receptors (GPCRs) as sensors to connect to the environment. GPCRs react to a variety of extracellular cues and are considered to play central roles in the signal transduction in fungi. Several species of the filamentous ascomycete Trichoderma are potent mycoparasites, i.e. can attack and parasitize other fungi, which turns them into successful bio-fungicides for the protection of plants against fungal phytopathogens. The identification and characterization of GPCRs will provide insights into how Trichoderma communicates with its environment and senses the presence of host fungi. Results We mined the recently published genomes of the two mycoparasitic biocontrol agents Trichoderma atroviride and Trichoderma virens and compared the identified GPCR-like proteins to those of the saprophyte Trichoderma reesei. Phylogenetic analyses resulted in 14 classes and revealed differences not only among the three Trichoderma species but also between Trichoderma and other fungi. The class comprising proteins of the PAQR family was significantly expanded both in Trichoderma compared to other fungi as well as in the two mycoparasites compared to T. reesei. Expression analysis of the PAQR-encoding genes of the three Trichoderma species revealed that all except one were actually transcribed. Furthermore, the class of receptors with a DUF300 domain was expanded in T. atroviride, and T. virens showed an expansion of PTH11-like receptors compared to T. atroviride and T. reesei. Conclusions Comparative genome analyses of three Trichoderma species revealed a great diversity of putative GPCRs with genus- and species- specific differences. The expansion of certain classes in the mycoparasites T. atroviride and T. virens is likely to reflect the capability of these fungi to establish various ecological niches and interactions with other organisms such as fungi and plants. These

  16. Species-specific considerations in using the fish embryo test as an alternative to identify endocrine disruption.

    Science.gov (United States)

    Schiller, Viktoria; Zhang, Xiaowei; Hecker, Markus; Schäfers, Christoph; Fischer, Rainer; Fenske, Martina

    2014-10-01

    A number of regulations have been implemented that aim to control the release of potentially adverse endocrine disrupters into the aquatic environment based on evidence from laboratory studies. Currently, such studies rely on testing approaches with adult fish because reliable alternatives have not been validated so far. Fish embryo tests have been proposed as such an alternative, and here we compared two species (medaka and zebrafish) to determine their suitability for the assessment of substances with estrogenic and anti-androgenic activity. Changes in gene expression (in here the phrase gene expression is used synonymously to gene transcription, although it is acknowledged that gene expression is additionally regulated, e.g., by translation and protein stability) patterns between the two species were compared in short term embryo exposure tests (medaka: 7-day post fertilization [dpf]; zebrafish: 48 and 96h post fertilization [hpf]) by using relative quantitative real-time RT-PCR. The tested genes were related to the hypothalamic-gonadal-axis and early steroidogenesis. Test chemicals included 17α-ethinylestradiol and flutamide as estrogenic and anti-androgenic reference compounds, respectively, as well as five additional substances with endocrine activities, namely bisphenol A, genistein, prochloraz, linuron and propanil. Estrogenic responses were comparable in 7-dpf medaka and 48/96-hpf zebrafish embryos and included transcriptional upregulation of aromatase b, vitellogenin 1 as well as steroidogenic genes, suggesting that both species reliably detected exposure to estrogenic compounds. However, anti-androgenic responses differed between the two species, with each species providing specific information concerning the mechanism of anti-androgenic disruption in fish embryos. Although small but significant changes in the expression of selected genes was observed in 48-hpf zebrafish embryos, exposure prolonged to 96hpf was necessary to obtain a response indicative

  17. Species-level para- and polyphyly in DNA barcode gene trees

    DEFF Research Database (Denmark)

    Mutanen, Marko; Kivelä, Sami M.; Vos, Rutger A.

    2016-01-01

    was paid to accurate species identification to ensure data integrity. We investigated the effects of tree-building method, sampling effort, and other methodological issues, all of which can influence estimates of non-monophyly. We found a 12% incidence of non-monophyly, a value significantly lower than...... between species and gene genealogies, as indicated by situations where conspecific individuals do not form a monophyletic cluster in a gene tree. In two previous reviews, non-monophyly has been reported as being common in mitochondrial DNA gene trees. We developed a novel web service "Monophylizer......" to detect non-monophyly in phylogenetic trees and used it to ascertain the incidence of species non-monophyly in COI (a.k.a. cox1) barcode sequence data from 4977 species and 41,583 specimens of European Lepidoptera, the largest data set of DNA barcodes analyzed from this regard. Particular attention...

  18. Social complexity parallels vocal complexity: a comparison of three nonhuman primate species

    Directory of Open Access Journals (Sweden)

    Hélène eBOUCHET

    2013-07-01

    Full Text Available Social factors play a key role in the structuring of vocal repertoires at the individual level, notably in nonhuman primates. Some authors suggested that, at the species level too, social life may have driven the evolution of communicative complexity, but this has rarely been empirically tested. Here, we use a comparative approach to address this issue. We investigated vocal variability, at both the call type and the repertoire levels, in three forest-dwelling species of Cercopithecinae presenting striking differences in their social systems, in terms of social organization as well as social structure. We collected female call recordings from twelve De Brazza’s monkeys (Cercopithecus neglectus, six Campbell’s monkeys (Cercopithecus campbelli and seven red-capped mangabeys (Cercocebus torquatus housed in similar conditions. First, we noted that the level of acoustic variability and individual distinctiveness found in several call types was related to their importance in social functioning. Contact calls, essential to intra-group cohesion, were the most individually distinctive regardless of the species, while threat calls were more structurally variable in mangabeys, the most ‘despotic’ of our three species. Second, we found a parallel between the degree of complexity of the species’ social structure and the size, diversity, and usage of its vocal repertoire. Mangabeys (most complex social structure called twice as often as guenons and displayed the largest and most complex repertoire. De Brazza’s monkeys (simplest social structure displayed the smallest and simplest repertoire. Campbell’s monkeys displayed an intermediate pattern. Providing evidence of higher levels of vocal variability in species presenting a more complex social system, our results are in line with the theory of a social-vocal coevolution of communicative abilities, opening new perspectives for comparative research on the evolution of communication systems in

  19. Developmental and environmental regulation of Aquaporin gene expression across Populus species: divergence or redundancy?

    Science.gov (United States)

    Cohen, David; Bogeat-Triboulot, Marie-Béatrice; Vialet-Chabrand, Silvère; Merret, Rémy; Courty, Pierre-Emmanuel; Moretti, Sébastien; Bizet, François; Guilliot, Agnès; Hummel, Irène

    2013-01-01

    Aquaporins (AQPs) are membrane channels belonging to the major intrinsic proteins family and are known for their ability to facilitate water movement. While in Populus trichocarpa, AQP proteins form a large family encompassing fifty-five genes, most of the experimental work focused on a few genes or subfamilies. The current work was undertaken to develop a comprehensive picture of the whole AQP gene family in Populus species by delineating gene expression domain and distinguishing responsiveness to developmental and environmental cues. Since duplication events amplified the poplar AQP family, we addressed the question of expression redundancy between gene duplicates. On these purposes, we carried a meta-analysis of all publicly available Affymetrix experiments. Our in-silico strategy controlled for previously identified biases in cross-species transcriptomics, a necessary step for any comparative transcriptomics based on multispecies design chips. Three poplar AQPs were not supported by any expression data, even in a large collection of situations (abiotic and biotic constraints, temporal oscillations and mutants). The expression of 11 AQPs was never or poorly regulated whatever the wideness of their expression domain and their expression level. Our work highlighted that PtTIP1;4 was the most responsive gene of the AQP family. A high functional divergence between gene duplicates was detected across species and in response to tested cues, except for the root-expressed PtTIP2;3/PtTIP2;4 pair exhibiting 80% convergent responses. Our meta-analysis assessed key features of aquaporin expression which had remained hidden in single experiments, such as expression wideness, response specificity and genotype and environment interactions. By consolidating expression profiles using independent experimental series, we showed that the large expansion of AQP family in poplar was accompanied with a strong divergence of gene expression, even if some cases of functional redundancy

  20. Developmental and environmental regulation of Aquaporin gene expression across Populus species: divergence or redundancy?

    Directory of Open Access Journals (Sweden)

    David Cohen

    Full Text Available Aquaporins (AQPs are membrane channels belonging to the major intrinsic proteins family and are known for their ability to facilitate water movement. While in Populus trichocarpa, AQP proteins form a large family encompassing fifty-five genes, most of the experimental work focused on a few genes or subfamilies. The current work was undertaken to develop a comprehensive picture of the whole AQP gene family in Populus species by delineating gene expression domain and distinguishing responsiveness to developmental and environmental cues. Since duplication events amplified the poplar AQP family, we addressed the question of expression redundancy between gene duplicates. On these purposes, we carried a meta-analysis of all publicly available Affymetrix experiments. Our in-silico strategy controlled for previously identified biases in cross-species transcriptomics, a necessary step for any comparative transcriptomics based on multispecies design chips. Three poplar AQPs were not supported by any expression data, even in a large collection of situations (abiotic and biotic constraints, temporal oscillations and mutants. The expression of 11 AQPs was never or poorly regulated whatever the wideness of their expression domain and their expression level. Our work highlighted that PtTIP1;4 was the most responsive gene of the AQP family. A high functional divergence between gene duplicates was detected across species and in response to tested cues, except for the root-expressed PtTIP2;3/PtTIP2;4 pair exhibiting 80% convergent responses. Our meta-analysis assessed key features of aquaporin expression which had remained hidden in single experiments, such as expression wideness, response specificity and genotype and environment interactions. By consolidating expression profiles using independent experimental series, we showed that the large expansion of AQP family in poplar was accompanied with a strong divergence of gene expression, even if some cases of

  1. Review and phylogenetic analysis of qac genes that reduce susceptibility to quaternary ammonium compounds in Staphylococcus species

    DEFF Research Database (Denmark)

    Wassenaar, Trudy M; Ussery, David; Nielsen, Lene Nørby

    2015-01-01

    The qac genes of Staphylococcus species encode multidrug efflux pumps: membrane proteins that export toxic molecules and thus increase tolerance to a variety of compounds such as disinfecting agents, including quaternary ammonium compounds (for which they are named), intercalating dyes and some...... described in the literature for qac detection may miss particular qac genes due to lack of DNA conservation. Despite their resemblance in substrate specificity, the Qac proteins belonging to the two protein families have little in common. QacA and QacB are highly conserved in Staphylococcus species, while...... qacA was also detected in Enterococcus faecalis, suggesting that these plasmid-born genes have spread across bacterial genera. Nevertheless, these qacA and qacB genes are quite dissimilar to their closest homologues in other organisms. In contrast, SMR-type Qac proteins display considerable sequence...

  2. Antibody Repertoire Development in Swine

    Czech Academy of Sciences Publication Activity Database

    Butler, J. E.; Wertz, N.; Šinkora, Marek

    2017-01-01

    Roč. 5, FEB 17 (2017), s. 255-279 ISSN 2165-8102 R&D Projects: GA ČR GA15-02274S; GA ČR(CZ) GA16-09296S Institutional support: RVO:61388971 Keywords : swine * pre-immune antibody repertoire * ileal Peyer's patches Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.708, year: 2016

  3. Gene specific actions of thyroid hormone receptor subtypes.

    Directory of Open Access Journals (Sweden)

    Jean Z Lin

    Full Text Available There are two homologous thyroid hormone (TH receptors (TRs α and β, which are members of the nuclear hormone receptor (NR family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3 in two cell backgrounds (HepG2 and HeLa. We find that hundreds of genes respond to T(3 or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3 response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3, TR regulation patterns and T(3 dose response. Cycloheximide (CHX treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs.

  4. Hybrid sterility and evolution in Hawaiian Drosophila: differential gene and allele-specific expression analysis of backcross males.

    Science.gov (United States)

    Brill, E; Kang, L; Michalak, K; Michalak, P; Price, D K

    2016-08-01

    The Hawaiian Drosophila are an iconic example of sequential colonization, adaptive radiation and speciation on islands. Genetic and phenotypic analysis of closely related species pairs that exhibit incomplete reproductive isolation can provide insights into the mechanisms of speciation. Drosophila silvestris from Hawai'i Island and Drosophila planitibia from Maui are two closely related allopatric Hawaiian picture-winged Drosophila that produce sterile F1 males but fertile F1 females, a pattern consistent with Haldane's rule. Backcrossing F1 hybrid females between these two species to parental species gives rise to recombinant males with three distinct sperm phenotypes despite a similar genomic background: motile sperm, no sperm (sterile), and immotile sperm. We found that these three reproductive morphologies of backcross hybrid males produce divergent gene expression profiles in testes, as measured with RNA sequencing. There were a total of 71 genes significantly differentially expressed between backcross males with no sperm compared with those backcross males with motile sperm and immotile sperm, but no significant differential gene expression between backcross males with motile sperm and backcross males with immotile sperm. All of these genes were underexpressed in males with no sperm, including a number of genes with previously known activities in adult testis. An allele-specific expression analysis showed overwhelmingly more cis-divergent than trans-divergent genes, with no significant difference in the ratio of cis- and trans-divergent genes among the sperm phenotypes. Overall, the results indicate that the regulation of gene expression involved in sperm production likely diverged relatively rapidly between these two closely related species.

  5. Phylogeographic support for horizontal gene transfer involving sympatric bruchid species

    Directory of Open Access Journals (Sweden)

    Grill Andrea

    2006-07-01

    Full Text Available Abstract Background We report on the probable horizontal transfer of a mitochondrial gene, cytb, between species of Neotropical bruchid beetles, in a zone where these species are sympatric. The bruchid beetles Acanthoscelides obtectus, A. obvelatus, A. argillaceus and Zabrotes subfasciatus develop on various bean species in Mexico. Whereas A. obtectus and A. obvelatus develop on Phaseolus vulgaris in the Mexican Altiplano, A. argillaceus feeds on P. lunatus in the Pacific coast. The generalist Z. subfasciatus feeds on both bean species, and is sympatric with A. obtectus and A. obvelatus in the Mexican Altiplano, and with A. argillaceus in the Pacific coast. In order to assess the phylogenetic position of these four species, we amplified and sequenced one nuclear (28S rRNA and two mitochondrial (cytb, COI genes. Results Whereas species were well segregated in topologies obtained for COI and 28S rRNA, an unexpected pattern was obtained in the cytb phylogenetic tree. In this tree, individuals from A. obtectus and A. obvelatus, as well as Z. subfasciatus individuals from the Mexican Altiplano, clustered together in a unique little variable monophyletic unit. In contrast, A. argillaceus and Z. subfasciatus individuals from the Pacific coast clustered in two separated clades, identically to the pattern obtained for COI and 28S rRNA. An additional analysis showed that Z. subfasciatus individuals from the Mexican Altiplano also possessed the cytb gene present in individuals of this species from the Pacific coast. Zabrotes subfasciatus individuals from the Mexican Altiplano thus demonstrated two cytb genes, an "original" one and an "infectious" one, showing 25% of nucleotide divergence. The "infectious" cytb gene seems to be under purifying selection and to be expressed in mitochondria. Conclusion The high degree of incongruence of the cytb tree with patterns for other genes is discussed in the light of three hypotheses: experimental contamination

  6. Phylogeographic support for horizontal gene transfer involving sympatric bruchid species.

    Science.gov (United States)

    Alvarez, Nadir; Benrey, Betty; Hossaert-McKey, Martine; Grill, Andrea; McKey, Doyle; Galtier, Nicolas

    2006-07-27

    We report on the probable horizontal transfer of a mitochondrial gene, cytb, between species of Neotropical bruchid beetles, in a zone where these species are sympatric. The bruchid beetles Acanthoscelides obtectus, A. obvelatus, A. argillaceus and Zabrotes subfasciatus develop on various bean species in Mexico. Whereas A. obtectus and A. obvelatus develop on Phaseolus vulgaris in the Mexican Altiplano, A. argillaceus feeds on P. lunatus in the Pacific coast. The generalist Z. subfasciatus feeds on both bean species, and is sympatric with A. obtectus and A. obvelatus in the Mexican Altiplano, and with A. argillaceus in the Pacific coast. In order to assess the phylogenetic position of these four species, we amplified and sequenced one nuclear (28S rRNA) and two mitochondrial (cytb, COI) genes. Whereas species were well segregated in topologies obtained for COI and 28S rRNA, an unexpected pattern was obtained in the cytb phylogenetic tree. In this tree, individuals from A. obtectus and A. obvelatus, as well as Z. subfasciatus individuals from the Mexican Altiplano, clustered together in a unique little variable monophyletic unit. In contrast, A. argillaceus and Z. subfasciatus individuals from the Pacific coast clustered in two separated clades, identically to the pattern obtained for COI and 28S rRNA. An additional analysis showed that Z. subfasciatus individuals from the Mexican Altiplano also possessed the cytb gene present in individuals of this species from the Pacific coast. Zabrotes subfasciatus individuals from the Mexican Altiplano thus demonstrated two cytb genes, an "original" one and an "infectious" one, showing 25% of nucleotide divergence. The "infectious" cytb gene seems to be under purifying selection and to be expressed in mitochondria. The high degree of incongruence of the cytb tree with patterns for other genes is discussed in the light of three hypotheses: experimental contamination, hybridization, and pseudogenisation. However, none of these

  7. Drug hypersensitivity caused by alteration of the MHC-presented self-peptide repertoire

    DEFF Research Database (Denmark)

    Ostrov, David A; Grant, Barry J; Pompeu, Yuri A

    2012-01-01

    cells, thus causing the equivalent of an alloreactive T-cell response. Indeed, we identified specific self-peptides that are presented only in the presence of abacavir and that were recognized by T cells of hypersensitive patients. The assays that we have established can be applied to test additional...... unclear. Here we show that abacavir can bind within the F pocket of the peptide-binding groove of HLA-B*57:01, thereby altering its specificity. This provides an explanation for HLA-linked idiosyncratic adverse drug reactions, namely that drugs can alter the repertoire of self-peptides presented to T...

  8. Gene expression variation resolves species and individual strains among coral-associated dinoflagellates within the genus Symbiodinium

    KAUST Repository

    Parkinson, John Everett; Baumgarten, Sebastian; Michell, Craig; Baums, Iliana B.; LaJeunesse, Todd C.; Voolstra, Christian R.

    2016-01-01

    Reef-building corals depend on symbiotic mutualisms with photosynthetic dinoflagellates in the genus Symbiodinium. This large microalgal group comprises many highly divergent lineages (“Clades A-I”) and hundreds of undescribed species. Given their ecological importance, efforts have turned to genomic approaches to characterize the functional ecology of Symbiodinium. To date, investigators have only compared gene expression between representatives from separate clades—the equivalent of contrasting genera or families in other dinoflagellate groups—making it impossible to distinguish between clade-level and species-level functional differences. Here, we examined the transcriptomes of four species within one Symbiodinium clade (Clade B) at ~20,000 orthologous genes, as well as multiple isoclonal cell lines within species (i.e. cultured strains). These species span two major adaptive radiations within Clade B, each encompassing both host-specialized and ecologically cryptic taxa. Species-specific expression differences were consistently enriched for photosynthesis-related genes, likely reflecting selection pressures driving niche diversification. Transcriptional variation among strains involved fatty acid metabolism and biosynthesis pathways. Such differences among individuals are potentially a major source of physiological variation, contributing to the functional diversity of coral holobionts composed of unique host-symbiont genotype pairings. Our findings expand the genomic resources available for this important symbiont group and emphasize the power of comparative transcriptomics as a method for studying speciation processes and inter-individual variation in non-model organisms.

  9. Gene expression variation resolves species and individual strains among coral-associated dinoflagellates within the genus Symbiodinium

    KAUST Repository

    Parkinson, John Everett

    2016-02-11

    Reef-building corals depend on symbiotic mutualisms with photosynthetic dinoflagellates in the genus Symbiodinium. This large microalgal group comprises many highly divergent lineages (“Clades A-I”) and hundreds of undescribed species. Given their ecological importance, efforts have turned to genomic approaches to characterize the functional ecology of Symbiodinium. To date, investigators have only compared gene expression between representatives from separate clades—the equivalent of contrasting genera or families in other dinoflagellate groups—making it impossible to distinguish between clade-level and species-level functional differences. Here, we examined the transcriptomes of four species within one Symbiodinium clade (Clade B) at ~20,000 orthologous genes, as well as multiple isoclonal cell lines within species (i.e. cultured strains). These species span two major adaptive radiations within Clade B, each encompassing both host-specialized and ecologically cryptic taxa. Species-specific expression differences were consistently enriched for photosynthesis-related genes, likely reflecting selection pressures driving niche diversification. Transcriptional variation among strains involved fatty acid metabolism and biosynthesis pathways. Such differences among individuals are potentially a major source of physiological variation, contributing to the functional diversity of coral holobionts composed of unique host-symbiont genotype pairings. Our findings expand the genomic resources available for this important symbiont group and emphasize the power of comparative transcriptomics as a method for studying speciation processes and inter-individual variation in non-model organisms.

  10. Quantification of Human Fecal Bifidobacterium Species by Use of Quantitative Real-Time PCR Analysis Targeting the groEL Gene

    Science.gov (United States)

    Junick, Jana

    2012-01-01

    Quantitative real-time PCR assays targeting the groEL gene for the specific enumeration of 12 human fecal Bifidobacterium species were developed. The housekeeping gene groEL (HSP60 in eukaryotes) was used as a discriminative marker for the differentiation of Bifidobacterium adolescentis, B. angulatum, B. animalis, B. bifidum, B. breve, B. catenulatum, B. dentium, B. gallicum, B. longum, B. pseudocatenulatum, B. pseudolongum, and B. thermophilum. The bifidobacterial chromosome contains a single copy of the groEL gene, allowing the determination of the cell number by quantification of the groEL copy number. Real-time PCR assays were validated by comparing fecal samples spiked with known numbers of a given Bifidobacterium species. Independent of the Bifidobacterium species tested, the proportion of groEL copies recovered from fecal samples spiked with 5 to 9 log10 cells/g feces was approximately 50%. The quantification limit was 5 to 6 log10 groEL copies/g feces. The interassay variability was less than 10%, and variability between different DNA extractions was less than 23%. The method developed was applied to fecal samples from healthy adults and full-term breast-fed infants. Bifidobacterial diversity in both adults and infants was low, with mostly ≤3 Bifidobacterium species and B. longum frequently detected. The predominant species in infant and adult fecal samples were B. breve and B. adolescentis, respectively. It was possible to distinguish B. catenulatum and B. pseudocatenulatum. We conclude that the groEL gene is a suitable molecular marker for the specific and accurate quantification of human fecal Bifidobacterium species by real-time PCR. PMID:22307308

  11. Phylogeny of Symbiotic Genes and the Symbiotic Properties of Rhizobia Specific to Astragalus glycyphyllos L.

    Science.gov (United States)

    Gnat, Sebastian; Małek, Wanda; Oleńska, Ewa; Wdowiak-Wróbel, Sylwia; Kalita, Michał; Łotocka, Barbara; Wójcik, Magdalena

    2015-01-01

    The phylogeny of symbiotic genes of Astragalus glycyphyllos L. (liquorice milkvetch) nodule isolates was studied by comparative sequence analysis of nodA, nodC, nodH and nifH loci. In all these genes phylograms, liquorice milkvetch rhizobia (closely related to bacteria of three species, i.e. Mesorhizobium amorphae, Mesorhizobium septentrionale and Mesorhizobium ciceri) formed one clearly separate cluster suggesting the horizontal transfer of symbiotic genes from a single ancestor to the bacteria being studied. The high sequence similarity of the symbiotic genes of A. glycyphyllos rhizobia (99-100% in the case of nodAC and nifH genes, and 98-99% in the case of nodH one) points to the relatively recent (in evolutionary scale) lateral transfer of these genes. In the nodACH and nifH phylograms, A. glycyphyllos nodule isolates were grouped together with the genus Mesorhizobium species in one monophyletic clade, close to M. ciceri, Mesorhizobium opportunistum and Mesorhizobium australicum symbiovar biserrulae bacteria, which correlates with the close relationship of these rhizobia host plants. Plant tests revealed the narrow host range of A. glycyphyllos rhizobia. They formed effective symbiotic interactions with their native host (A. glycyphyllos) and Amorpha fruticosa but not with 11 other fabacean species. The nodules induced on A. glycyphyllos roots were indeterminate with apical, persistent meristem, an age gradient of nodule tissues and cortical vascular bundles. To reflect the symbiosis-adaptive phenotype of rhizobia, specific for A. glycyphyllos, we propose for these bacteria the new symbiovar "glycyphyllae", based on nodA and nodC genes sequences.

  12. Dichotomy in the NRT gene families of dicots and grass species.

    Directory of Open Access Journals (Sweden)

    Darren Plett

    Full Text Available A large proportion of the nitrate (NO(3(- acquired by plants from soil is actively transported via members of the NRT families of NO(3(- transporters. In Arabidopsis, the NRT1 family has eight functionally characterised members and predominantly comprises low-affinity transporters; the NRT2 family contains seven members which appear to be high-affinity transporters; and there are two NRT3 (NAR2 family members which are known to participate in high-affinity transport. A modified reciprocal best hit (RBH approach was used to identify putative orthologues of the Arabidopsis NRT genes in the four fully sequenced grass genomes (maize, rice, sorghum, Brachypodium. We also included the poplar genome in our analysis to establish whether differences between Arabidopsis and the grasses may be generally applicable to monocots and dicots. Our analysis reveals fundamental differences between Arabidopsis and the grass species in the gene number and family structure of all three families of NRT transporters. All grass species possessed additional NRT1.1 orthologues and appear to lack NRT1.6/NRT1.7 orthologues. There is significant separation in the NRT2 phylogenetic tree between NRT2 genes from dicots and grass species. This indicates that determination of function of NRT2 genes in grass species will not be possible in cereals based simply on sequence homology to functionally characterised Arabidopsis NRT2 genes and that proper functional analysis will be required. Arabidopsis has a unique NRT3.2 gene which may be a fusion of the NRT3.1 and NRT3.2 genes present in all other species examined here. This work provides a framework for future analysis of NO(3(- transporters and NO(3(- transport in grass crop species.

  13. Species Authentication of Common Meat Based on PCR Analysis of the Mitochondrial COI Gene.

    Science.gov (United States)

    Dai, Zhenyu; Qiao, Jiao; Yang, Siran; Hu, Shen; Zuo, Jingjing; Zhu, Weifeng; Huang, Chunhong

    2015-07-01

    Adulteration of meat products and costly animal-derived commodities with their inferior/cheaper counterparts is a grievous global problem. Species authentication is still technical challenging, especially to those deep processed products. The present study described the design of seven sets of species-specific primer based on a high heterozygous region of mitochondrial cytochrome c oxidase subunit I (COI) gene. These primers were proven to have high species specificity and no cross-reactions and unexpected products to different DNA source. Multiplex PCR assay was achieved for rapid and economical identification of four commonly consumed meats (pork, beef, chicken, and mutton). The conventional PCR assay was sensitive down to 0.001 ng of DNA template in the reactant. The developed method was also powerful in detecting as low as 0.1-mg adulterated pork (0.05 % in wt/wt) in an artificial counterfeited mutton. Validation test showed that the assay is specific, reproducible, and robust in commercial deep processed meats, leatherware, and feather commodities. This proposed method will be greatly beneficial to the consumers, food industry, leather, and feather commodity manufacture.

  14. The identification of genes specific to Prevotella intermedia and Prevotella nigrescens using genomic subtractive hybridization.

    Science.gov (United States)

    Masakiyo, Yoshiaki; Yoshida, Akihiro; Shintani, Yasuyuki; Takahashi, Yusuke; Ansai, Toshihiro; Takehara, Tadamichi

    2010-06-01

    Prevotella intermedia and Prevotella nigrescens, which are often isolated from periodontal sites, were once considered two different genotypes of P. intermedia. Although the genomic sequence of P. intermedia was determined recently, little is known about the genetic differences between P. intermedia and P. nigrescens. The subtractive hybridization technique is a powerful method for generating a set of DNA fragments differing between two closely related bacterial strains or species. We used subtractive hybridization to identify the DNA regions specific to P. intermedia ATCC 25611 and P. nigrescens ATCC 25261. Using this method, four P. intermedia ATCC 25611-specific and three P. nigrescens ATCC 25261-specific regions were determined. From the species-specific regions, insertion sequence (IS) elements were isolated for P. intermedia. IS elements play an important role in the pathogenicity of bacteria. For the P. intermedia-specific regions, the genes adenine-specific DNA-methyltransferase and 8-amino-7-oxononanoate synthase were isolated. The P. nigrescens-specific region contained a Flavobacterium psychrophilum SprA homologue, a cell-surface protein involved in gliding motility, Prevotella melaninogenica ATCC 25845 glutathione peroxide, and Porphyromonas gingivalis ATCC 33277 leucyl-tRNA synthetase. The results demonstrate that the subtractive hybridization technique was useful for distinguishing between the two closely related species. Furthermore, this technique will contribute to our understanding of the virulence of these species. 2009 Elsevier Ltd. All rights reserved.

  15. STRIDE: Species Tree Root Inference from Gene Duplication Events.

    Science.gov (United States)

    Emms, David M; Kelly, Steven

    2017-12-01

    The correct interpretation of any phylogenetic tree is dependent on that tree being correctly rooted. We present STRIDE, a fast, effective, and outgroup-free method for identification of gene duplication events and species tree root inference in large-scale molecular phylogenetic analyses. STRIDE identifies sets of well-supported in-group gene duplication events from a set of unrooted gene trees, and analyses these events to infer a probability distribution over an unrooted species tree for the location of its root. We show that STRIDE correctly identifies the root of the species tree in multiple large-scale molecular phylogenetic data sets spanning a wide range of timescales and taxonomic groups. We demonstrate that the novel probability model implemented in STRIDE can accurately represent the ambiguity in species tree root assignment for data sets where information is limited. Furthermore, application of STRIDE to outgroup-free inference of the origin of the eukaryotic tree resulted in a root probability distribution that provides additional support for leading hypotheses for the origin of the eukaryotes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. Cryptic species? Patterns of maternal and paternal gene flow in eight neotropical bats.

    Directory of Open Access Journals (Sweden)

    Elizabeth L Clare

    Full Text Available Levels of sequence divergence at mitochondrial loci are frequently used in phylogeographic analysis and species delimitation though single marker systems cannot assess bi-parental gene flow. In this investigation I compare the phylogeographic patterns revealed through the maternally inherited mitochondrial COI region and the paternally inherited 7(th intron region of the Dby gene on the Y-chromosome in eight common Neotropical bat species. These species are diverse and include members of two families from the feeding guilds of sanguivores, nectarivores, frugivores, carnivores and insectivores. In each case, the currently recognized taxon is comprised of distinct, substantially divergent intraspecific mitochondrial lineages suggesting cryptic species complexes. In Chrotopterus auritus, and Saccopteryx bilineata I observed congruent patterns of divergence in both genetic regions suggesting a cessation of gene flow between intraspecific groups. This evidence supports the existence of cryptic species complexes which meet the criteria of the genetic species concept. In Glossophaga soricina two intraspecific groups with largely sympatric South American ranges show evidence for incomplete lineage sorting or frequent hybridization while a third group with a Central American distribution appears to diverge congruently at both loci suggesting speciation. Within Desmodus rotundus and Trachops cirrhosus the paternally inherited region was monomorphic and thus does not support or refute the potential for cryptic speciation. In Uroderma bilobatum, Micronycteris megalotis and Platyrrhinus helleri the gene regions show conflicting patterns of divergence and I cannot exclude ongoing gene flow between intraspecific groups. This analysis provides a comprehensive comparison across taxa and employs both maternally and paternally inherited gene regions to validate patterns of gene flow. I present evidence for previously unrecognized species meeting the criteria of

  17. Inferring species trees from incongruent multi-copy gene trees using the Robinson-Foulds distance

    Science.gov (United States)

    2013-01-01

    Background Constructing species trees from multi-copy gene trees remains a challenging problem in phylogenetics. One difficulty is that the underlying genes can be incongruent due to evolutionary processes such as gene duplication and loss, deep coalescence, or lateral gene transfer. Gene tree estimation errors may further exacerbate the difficulties of species tree estimation. Results We present a new approach for inferring species trees from incongruent multi-copy gene trees that is based on a generalization of the Robinson-Foulds (RF) distance measure to multi-labeled trees (mul-trees). We prove that it is NP-hard to compute the RF distance between two mul-trees; however, it is easy to calculate this distance between a mul-tree and a singly-labeled species tree. Motivated by this, we formulate the RF problem for mul-trees (MulRF) as follows: Given a collection of multi-copy gene trees, find a singly-labeled species tree that minimizes the total RF distance from the input mul-trees. We develop and implement a fast SPR-based heuristic algorithm for the NP-hard MulRF problem. We compare the performance of the MulRF method (available at http://genome.cs.iastate.edu/CBL/MulRF/) with several gene tree parsimony approaches using gene tree simulations that incorporate gene tree error, gene duplications and losses, and/or lateral transfer. The MulRF method produces more accurate species trees than gene tree parsimony approaches. We also demonstrate that the MulRF method infers in minutes a credible plant species tree from a collection of nearly 2,000 gene trees. Conclusions Our new phylogenetic inference method, based on a generalized RF distance, makes it possible to quickly estimate species trees from large genomic data sets. Since the MulRF method, unlike gene tree parsimony, is based on a generic tree distance measure, it is appealing for analyses of genomic data sets, in which many processes such as deep coalescence, recombination, gene duplication and losses as

  18. Genome-Wide Transcriptional Profiling of Clostridium perfringens SM101 during Sporulation Extends the Core of Putative Sporulation Genes and Genes Determining Spore Properties and Germination Characteristics.

    Science.gov (United States)

    Xiao, Yinghua; van Hijum, Sacha A F T; Abee, Tjakko; Wells-Bennik, Marjon H J

    2015-01-01

    The formation of bacterial spores is a highly regulated process and the ultimate properties of the spores are determined during sporulation and subsequent maturation. A wide variety of genes that are expressed during sporulation determine spore properties such as resistance to heat and other adverse environmental conditions, dormancy and germination responses. In this study we characterized the sporulation phases of C. perfringens enterotoxic strain SM101 based on morphological characteristics, biomass accumulation (OD600), the total viable counts of cells plus spores, the viable count of heat resistant spores alone, the pH of the supernatant, enterotoxin production and dipicolinic acid accumulation. Subsequently, whole-genome expression profiling during key phases of the sporulation process was performed using DNA microarrays, and genes were clustered based on their time-course expression profiles during sporulation. The majority of previously characterized C. perfringens germination genes showed upregulated expression profiles in time during sporulation and belonged to two main clusters of genes. These clusters with up-regulated genes contained a large number of C. perfringens genes which are homologs of Bacillus genes with roles in sporulation and germination; this study therefore suggests that those homologs are functional in C. perfringens. A comprehensive homology search revealed that approximately half of the upregulated genes in the two clusters are conserved within a broad range of sporeforming Firmicutes. Another 30% of upregulated genes in the two clusters were found only in Clostridium species, while the remaining 20% appeared to be specific for C. perfringens. These newly identified genes may add to the repertoire of genes with roles in sporulation and determining spore properties including germination behavior. Their exact roles remain to be elucidated in future studies.

  19. Response of cyprid specific genes to natural settlement cues in the barnacle Balanus (=Amphibalanus) amphitrite

    KAUST Repository

    Li, Honglei; Thiyagarajan, Vengatesen; Qian, Pei Yuan

    2010-01-01

    Quantitative real-time PCR was used to further our understanding of the molecular processes involved in the attachment and metamorphosis of larval barnacles. We report the effects of natural settlement cues (microbial biofilms and conspecific settlement-inducing factor) on the expression profiles of six barnacle cyprid specific (bcs) genes in cyprids of the barnacle Balanus (=Amphibalanus) amphitrite Darwin. Genes bcs-1 to bcs-5 all showed marked decreases in their expression between initial cyprid attachment and the completion of metamorphosis, whereas bcs-6 showed significant up-regulation. Generally, settlement cues exerted no significant effect on the decreasing trend of bcs-1 to bcs-5 expression during attachment and metamorphosis. However, the expression of bcs-6 increased prior to cyprid attachment in response to both settlement cues. This elevated expression of bcs-6 gene indicates the importance and key regulatory role of this specific gene to larval attachment and metamorphosis in this barnacle species. © 2010 Elsevier B.V. All rights reserved.

  20. Response of cyprid specific genes to natural settlement cues in the barnacle Balanus (=Amphibalanus) amphitrite

    KAUST Repository

    Li, Honglei

    2010-06-01

    Quantitative real-time PCR was used to further our understanding of the molecular processes involved in the attachment and metamorphosis of larval barnacles. We report the effects of natural settlement cues (microbial biofilms and conspecific settlement-inducing factor) on the expression profiles of six barnacle cyprid specific (bcs) genes in cyprids of the barnacle Balanus (=Amphibalanus) amphitrite Darwin. Genes bcs-1 to bcs-5 all showed marked decreases in their expression between initial cyprid attachment and the completion of metamorphosis, whereas bcs-6 showed significant up-regulation. Generally, settlement cues exerted no significant effect on the decreasing trend of bcs-1 to bcs-5 expression during attachment and metamorphosis. However, the expression of bcs-6 increased prior to cyprid attachment in response to both settlement cues. This elevated expression of bcs-6 gene indicates the importance and key regulatory role of this specific gene to larval attachment and metamorphosis in this barnacle species. © 2010 Elsevier B.V. All rights reserved.

  1. Understanding the Broad Substrate Repertoire of Nitroreductase Based on Its Kinetic Mechanism*

    Science.gov (United States)

    Pitsawong, Warintra; Hoben, John P.; Miller, Anne-Frances

    2014-01-01

    The oxygen-insensitive nitroreductase from Enterobacter cloacae (NR) catalyzes two-electron reduction of nitroaromatics to the corresponding nitroso compounds and, subsequently, to hydroxylamine products. NR has an unusually broad substrate repertoire, which may be related to protein dynamics (flexibility) and/or a simple non-selective kinetic mechanism. To investigate the possible role of mechanism in the broad substrate repertoire of NR, the kinetics of oxidation of NR by para-nitrobenzoic acid (p-NBA) were investigated using stopped-flow techniques at 4 °C. The results revealed a hyperbolic dependence on the p-NBA concentration with a limiting rate of 1.90 ± 0.09 s−1, indicating one-step binding before the flavin oxidation step. There is no evidence for a distinct binding step in which specificity might be enforced. The reduction of p-NBA is rate-limiting in steady-state turnover (1.7 ± 0.3 s−1). The pre-steady-state reduction kinetics of NR by NADH indicate that NADH reduces the enzyme with a rate constant of 700 ± 20 s−1 and a dissociation constant of 0.51 ± 0.04 mm. Thus, we demonstrate simple transient kinetics in both the reductive and oxidative half-reactions that help to explain the broad substrate repertoire of NR. Finally, we tested the ability of NR to reduce para-hydroxylaminobenzoic acid, demonstrating that the corresponding amine does not accumulate to significant levels even under anaerobic conditions. Thus E. cloacae NR is not a good candidate for enzymatic production of aromatic amines. PMID:24706760

  2. Acquisition of repertoires of suppressor T cells under the influence of macrophages

    International Nuclear Information System (INIS)

    Soejima, T.; Nagayama, A.; Sado, T.; Taniguchi, M.

    1988-01-01

    Acquisition of repertoires and genetic restriction specificities of suppressor T cells (Ts) and their factors were studied by using full allogeneic radiation bone marrow chimera and H-2 congenic pairs, B10.A(3R) and B10.A(5R), which received conventional or cloned macrophages by cell transfer. Suppressor T-cell factor (TsF) from C3H----C57BL/6 or C57BL/6----C3H chimera suppressed only donor but not host-type responses of either C3H or C57BL/6, in an antigen-specific fashion. However, if chimera mice were given conventional or cloned macrophages of the host type, the chimera TsF in turn suppressed both the responses of C3H and C57BL/6 mice but not those of the third party, BALB/c, indicating that macrophages are responsible for the acquisition of host restriction specificity. Similarly, B10.A(5R) mice developed I-Jb restricted Ts or TsF when the B10.A(3R) macrophage cell line was injected at the time of antigen priming. The reverse was also true. B10.A(3R) mice did generate I-Jk restricted Ts when they received the B10.A(5R) macrophage cell line. Thus, the results clearly demonstrated that B10.A(3R) or B10.A(5R) mice potentially possessed their ability to express both I-Jk and I-Jb determinants and that repertoires and genetic restriction specificity of Ts and their TsF were acquired at a macrophage level at the time of antigen-priming

  3. Species-specific activity of SIV Nef and HIV-1 Vpu in overcoming restriction by tetherin/BST2.

    Directory of Open Access Journals (Sweden)

    Bin Jia

    2009-05-01

    Full Text Available Tetherin, also known as BST2, CD317 or HM1.24, was recently identified as an interferon-inducible host-cell factor that interferes with the detachment of virus particles from infected cells. HIV-1 overcomes this restriction by expressing an accessory protein, Vpu, which counteracts tetherin. Since lentiviruses of the SIV(smm/mac/HIV-2 lineage do not have a vpu gene, this activity has likely been assumed by other viral gene products. We found that deletion of the SIV(mac239 nef gene significantly impaired virus release in cells expressing rhesus macaque tetherin. Virus release could be restored by expressing Nef in trans. However, Nef was unable to facilitate virus release in the presence of human tetherin. Conversely, Vpu enhanced virus release in the presence of human tetherin, but not in the presence of rhesus tetherin. In accordance with the species-specificity of Nef in mediating virus release, SIV Nef downregulated cell-surface expression of rhesus tetherin, but did not downregulate human tetherin. The specificity of SIV Nef for rhesus tetherin mapped to four amino acids in the cytoplasmic domain of the molecule that are missing from human tetherin, whereas the specificity of Vpu for human tetherin mapped to amino acid differences in the transmembrane domain. Nef alleles of SIV(smm, HIV-2 and HIV-1 were also able to rescue virus release in the presence of both rhesus macaque and sooty mangabey tetherin, but were generally ineffective against human tetherin. Thus, the ability of Nef to antagonize tetherin from these Old World primates appears to be conserved among the primate lentiviruses. These results identify Nef as the viral gene product of SIV that opposes restriction by tetherin in rhesus macaques and sooty mangabeys, and reveal species-specificity in the activities of both Nef and Vpu in overcoming tetherin in their respective hosts.

  4. Are temperate canopy spiders tree-species specific?

    Science.gov (United States)

    Mupepele, Anne-Christine; Müller, Tobias; Dittrich, Marcus; Floren, Andreas

    2014-01-01

    Arboreal spiders in deciduous and coniferous trees were investigated on their distribution and diversity. Insecticidal knock-down was used to comprehensively sample spiders from 175 trees from 2001 to 2003 in the Białowieża forest and three remote forests in Poland. We identified 140 species from 9273 adult spiders. Spider communities were distinguished between deciduous and coniferous trees. The richest fauna was collected from Quercus where beta diversity was also highest. A tree-species-specific pattern was clearly observed for Alnus, Carpinus, Picea and Pinus trees and also for those tree species that were fogged in only four or three replicates, namely Betula and Populus. This hitherto unrecognised association was mainly due to the community composition of common species identified in a Dufrene-Legendre indicator species analysis. It was not caused by spatial or temporal autocorrelation. Explaining tree-species specificity for generalist predators like spiders is difficult and has to involve physical and ecological tree parameters like linkage with the abundance of prey species. However, neither did we find a consistent correlation of prey group abundances with spiders nor could differences in spider guild composition explain the observed pattern. Our results hint towards the importance of deterministic mechanisms structuring communities of generalist canopy spiders although the casual relationship is not yet understood.

  5. Comparative analyses identified species-specific functional roles in oral microbial genomes

    Science.gov (United States)

    Chen, Tsute; Gajare, Prasad; Olsen, Ingar; Dewhirst, Floyd E.

    2017-01-01

    ABSTRACT The advent of next generation sequencing is producing more genomic sequences for various strains of many human oral microbial species and allows for insightful functional comparisons at both intra- and inter-species levels. This study performed in-silico functional comparisons for currently available genomic sequences of major species associated with periodontitis including Aggregatibacter actinomycetemcomitans (AA), Porphyromonas gingivalis (PG), Treponema denticola (TD), and Tannerella forsythia (TF), as well as several cariogenic and commensal streptococcal species. Complete or draft sequences were annotated with the RAST to infer structured functional subsystems for each genome. The subsystems profiles were clustered to groups of functions with similar patterns. Functional enrichment and depletion were evaluated based on hypergeometric distribution to identify subsystems that are unique or missing between two groups of genomes. Unique or missing metabolic pathways and biological functions were identified in different species. For example, components involved in flagellar motility were found only in the motile species TD, as expected, with few exceptions scattered in several streptococcal species, likely associated with chemotaxis. Transposable elements were only found in the two Bacteroidales species PG and TF, and half of the AA genomes. Genes involved in CRISPR were prevalent in most oral species. Furthermore, prophage related subsystems were also commonly found in most species except for PG and Streptococcus mutans, in which very few genomes contain prophage components. Comparisons between pathogenic (P) and nonpathogenic (NP) genomes also identified genes potentially important for virulence. Two such comparisons were performed between AA (P) and several A. aphrophilus (NP) strains, and between S. mutans + S. sobrinus (P) and other oral streptococcal species (NP). This comparative genomics approach can be readily used to identify functions unique to

  6. Immunoglobulin gene usage in the human anti-pathogen response.

    Science.gov (United States)

    Newkirk, M M; Rioux, J D

    1995-09-01

    The human antibody response to foreign pathogens is generated to a relatively small number of target surface proteins and carbohydrates that nonetheless have an extensive array of epitopes. The study of human monoclonal antibodies to different pathogens shows that there are a diversity of mechanisms used to generate a sufficient repertoire of antibodies to combat the invading pathogens. Although many different immunoglobulin gene elements are used to construct the anti-pathogen response, some elements are used more often than would be expected if all elements were used randomly. For example, the immune response to Haemophilus influenzae polysaccharide appears to be quite narrow, being restricted primarily to a specific heavy-chain gene, 3-15, and a lambda light-chain family II member, 4A. In contrast, for the immune response to cytomegalovirus proteins, a wider group of gene elements is needed. It is also surprising that despite an investigator bias for IgG- rather than IgM-secreting immortal B cells (because of their high affinity and neutralizing abilities), 26% of light chains and 13% of heavy chains showed a very low level of somatic mutation, equivalent to an IgM molecule that has not undergone affinity maturation. Although some highly mutated IgG molecules are present in the anti-pathogen response, most of the monoclonal antibodies specific for viruses or bacteria have a level of somatic hypermutation similar to that of the adult IgM repertoire. A number of studies have shown that there are similarities in the antibody responses to pathogens and to self (autoantibodies).(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Differentiation of Actinobacillus pleuropneumoniae strains by sequence analysis of 16S rDNA and ribosomal intergenic regions, and development of a species specific oligonucleotide for in situ detection

    DEFF Research Database (Denmark)

    Fussing, Vivian; Paster, Bruce J.; Dewhirst, Floyd E.

    1998-01-01

    . The larger RIS's were different between the 3 species tested. The sequence of the 16S ribosomal gene was determined for 8 serotypes of A. pleuropneumoniae. These sequences showed only minor base differences, indicating a close genetic relatedness of these serotypes within the species. An oligonucleotide DNA...... probe designed from the 16S rRNA gene sequence of A. pleuropneumoniae was specific for all strains of the target species and did not cross react with A. lignieresii, the closest known relative of A. pleuropneumoniae. This species-specific DNA probe labeled with fluorescein was used for in situ......The aims of this study were to characterize and determine intraspecies and interspecies relatedness of Actinobacillus pleuropneumoniae to Actinobacillus lignieresii and Actinobacillus suis by sequence analysis of the ribosomal operon and to find a species-specific area for in situ detection of A...

  8. Transcription profiling and identification of infection-related genes in Phytophthora cactorum.

    Science.gov (United States)

    Chen, Xiao-Ren; Huang, Shen-Xin; Zhang, Ye; Sheng, Gui-Lin; Zhang, Bo-Yue; Li, Qi-Yuan; Zhu, Feng; Xu, Jing-You

    2018-04-01

    Phytophthora cactorum, an oomycete pathogen, infects more than 200 plant species within several plant families. To gain insight into the repertoire of the infection-related genes of P. cactorum, Illumina RNA-Seq was used to perform a global transcriptome analysis of three life cycle stages of the pathogen, mycelia (MY), zoospores (ZO) and germinating cysts with germ tubes (GC). From over 9.8 million Illumina reads for each library, 18,402, 18,569 and 19,443 distinct genes were identified for MY, ZO and GC libraries, respectively. Furthermore, the transcriptome difference among MY, ZO and GC stages was investigated. Gene ontology (GO) and KEGG pathway enrichment analyses revealed diverse biological functions and processes. Comparative analysis identified a large number of genes that are associated with specific stages and pathogenicity, including 166 effector genes. Of them, most of RXLR and NLP genes showed induction while the majority of CRN genes were down-regulated in GC, the important pre-infection stage, compared to either MY or ZO. And 14 genes encoding small cysteine-rich (SCR) secretory proteins showed differential expression during the developmental stages and in planta. Ectopic expression in the Solanaceae indicated that SCR113 and one elicitin PcINF1 can trigger cell death on Nicotiana benthamiana, tobacco (N. tabacum) and tomato (Solanum lycopersicum) leaves. Neither conserved domain nor homologues of SCR113 in other organisms can be identified. Collectively, our study provides a comprehensive examination of gene expression across three P. cactorum developmental stages and describes pathogenicity-related genes, all of which will help elucidate the pathogenicity mechanism of this destructive pathogen.

  9. Analysis of immunoglobulin transcripts in the ostrich Struthio camelus, a primitive avian species.

    Directory of Open Access Journals (Sweden)

    Tian Huang

    Full Text Available Previous studies on the immunoglobulin (Ig genes in avian species are limited (mainly to galliformes and anseriformes but have revealed several interesting features, including the absence of the IgD and Igκ encoding genes, inversion of the IgA encoding gene and the use of gene conversion as the primary mechanism to generate an antibody repertoire. To better understand the Ig genes and their evolutionary development in birds, we analyzed the Ig genes in the ostrich (Struthio camelus, which is one of the most primitive birds. Similar to the chicken and duck, the ostrich expressed only three IgH chain isotypes (IgM, IgA and IgY and λ light chains. The IgM and IgY constant domains are similar to their counterparts described in other vertebrates. Although conventional IgM, IgA and IgY cDNAs were identified in the ostrich, we also detected a transcript encoding a short membrane-bound form of IgA (lacking the last two C(H exons that was undetectable at the protein level. No IgD or κ encoding genes were identified. The presence of a single leader peptide in the expressed heavy chain and light chain V regions indicates that gene conversion also plays a major role in the generation of antibody diversity in the ostrich. Because the ostrich is one of the most primitive living aves, this study suggests that the distinct features of the bird Ig genes appeared very early during the divergence of the avian species and are thus shared by most, if not all, avian species.

  10. Genome-Wide Comparison of Magnaporthe Species Reveals a Host-Specific Pattern of Secretory Proteins and Transposable Elements.

    Directory of Open Access Journals (Sweden)

    Meghana Deepak Shirke

    Full Text Available Blast disease caused by the Magnaporthe species is a major factor affecting the productivity of rice, wheat and millets. This study was aimed at generating genomic information for rice and non-rice Magnaporthe isolates to understand the extent of genetic variation. We have sequenced the whole genome of the Magnaporthe isolates, infecting rice (leaf and neck, finger millet (leaf and neck, foxtail millet (leaf and buffel grass (leaf. Rice and finger millet isolates infecting both leaf and neck tissues were sequenced, since the damage and yield loss caused due to neck blast is much higher as compared to leaf blast. The genome-wide comparison was carried out to study the variability in gene content, candidate effectors, repeat element distribution, genes involved in carbohydrate metabolism and SNPs. The analysis of repeat element footprints revealed some genes such as naringenin, 2-oxoglutarate 3-dioxygenase being targeted by Pot2 and Occan, in isolates from different host species. Some repeat insertions were host-specific while other insertions were randomly shared between isolates. The distributions of repeat elements, secretory proteins, CAZymes and SNPs showed significant variation across host-specific lineages of Magnaporthe indicating an independent genome evolution orchestrated by multiple genomic factors.

  11. Rule-Governed Behavior: Teaching a Preliminary Repertoire of Rule-Following to Children With Autism

    OpenAIRE

    Tarbox, Jonathan; Zuckerman, Carrie K; Bishop, Michele R; Olive, Melissa L; O'Hora, Denis P

    2011-01-01

    Rule-governed behavior is generally considered an integral component of complex verbal repertoires but has rarely been the subject of empirical research. In particular, little or no previous research has attempted to establish rule-governed behavior in individuals who do not already display the repertoire. This study consists of two experiments that evaluated multiple exemplar training procedures for teaching a simple component skill, which may be necessary for developing a repertoire of rule...

  12. Gene flow among wild and domesticated almond species: insights from chloroplast and nuclear markers

    Science.gov (United States)

    Delplancke, Malou; Alvarez, Nadir; Espíndola, Anahí; Joly, Hélène; Benoit, Laure; Brouck, Elise; Arrigo, Nils

    2012-01-01

    Hybridization has played a central role in the evolutionary history of domesticated plants. Notably, several breeding programs relying on gene introgression from the wild compartment have been performed in fruit tree species within the genus Prunus but few studies investigated spontaneous gene flow among wild and domesticated Prunus species. Consequently, a comprehensive understanding of genetic relationships and levels of gene flow between domesticated and wild Prunus species is needed. Combining nuclear and chloroplastic microsatellites, we investigated the gene flow and hybridization among two key almond tree species, the cultivated Prunus dulcis and one of the most widespread wild relative Prunus orientalis in the Fertile Crescent. We detected high genetic diversity levels in both species along with substantial and symmetric gene flow between the domesticated P. dulcis and the wild P. orientalis. These results were discussed in light of the cultivated species diversity, by outlining the frequent spontaneous genetic contributions of wild species to the domesticated compartment. In addition, crop-to-wild gene flow suggests that ad hoc transgene containment strategies would be required if genetically modified cultivars were introduced in the northwestern Mediterranean. PMID:25568053

  13. Direct Detection and Differentiation of Pathogenic Leptospira Species Using a Multi-Gene Targeted Real Time PCR Approach

    Science.gov (United States)

    Ferreira, Ana Sofia; Costa, Pedro; Rocha, Teresa; Amaro, Ana; Vieira, Maria Luísa; Ahmed, Ahmed; Thompson, Gertrude; Hartskeerl, Rudy A.; Inácio, João

    2014-01-01

    Leptospirosis is a growing public and veterinary health concern caused by pathogenic species of Leptospira. Rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. In this work we describe a novel and simple TaqMan-based multi-gene targeted real-time PCR approach able to detect and differentiate Leptospira interrogans, L. kirschneri, L. borgpeteresenii and L. noguchii, which constitute the veterinary most relevant pathogenic species of Leptospira. The method uses sets of species-specific probes, and respective flanking primers, designed from ompL1 and secY gene sequences. To monitor the presence of inhibitors, a duplex amplification assay targeting both the mammal β-actin and the leptospiral lipL32 genes was implemented. The analytical sensitivity of all primer and probe sets was estimated to be <10 genome equivalents (GE) in the reaction mixture. Application of the amplification reactions on genomic DNA from a variety of pathogenic and non-pathogenic Leptospira strains and other non-related bacteria revealed a 100% analytical specificity. Additionally, pathogenic leptospires were successfully detected in five out of 29 tissue samples from animals (Mus spp., Rattus spp., Dolichotis patagonum and Sus domesticus). Two samples were infected with L. borgpetersenii, two with L. interrogans and one with L. kirschneri. The possibility to detect and identify these pathogenic agents to the species level in domestic and wildlife animals reinforces the diagnostic information and will enhance our understanding of the epidemiology of leptopirosis. PMID:25398140

  14. Early events in the evolution of spider silk genes.

    Directory of Open Access Journals (Sweden)

    James Starrett

    Full Text Available Silk spinning is essential to spider ecology and has had a key role in the expansive diversification of spiders. Silk is composed primarily of proteins called spidroins, which are encoded by a multi-gene family. Spidroins have been studied extensively in the derived clade, Orbiculariae (orb-weavers, from the suborder Araneomorphae ('true spiders'. Orbicularians produce a suite of different silks, and underlying this repertoire is a history of duplication and spidroin gene divergence. A second class of silk proteins, Egg Case Proteins (ECPs, is known only from the orbicularian species, Lactrodectus hesperus (Western black widow. In L. hesperus, ECPs bond with tubuliform spidroins to form egg case silk fibers. Because most of the phylogenetic diversity of spiders has not been sampled for their silk genes, there is limited understanding of spidroin gene family history and the prevalence of ECPs. Silk genes have not been reported from the suborder Mesothelae (segmented spiders, which diverged from all other spiders >380 million years ago, and sampling from Mygalomorphae (tarantulas, trapdoor spiders and basal araneomorph lineages is sparse. In comparison to orbicularians, mesotheles and mygalomorphs have a simpler silk biology and thus are hypothesized to have less diversity of silk genes. Here, we present cDNAs synthesized from the silk glands of six mygalomorph species, a mesothele, and a non-orbicularian araneomorph, and uncover a surprisingly rich silk gene diversity. In particular, we find ECP homologs in the mesothele, suggesting that ECPs were present in the common ancestor of extant spiders, and originally were not specialized to complex with tubuliform spidroins. Furthermore, gene-tree/species-tree reconciliation analysis reveals that numerous spidroin gene duplications occurred after the split between Mesothelae and Opisthothelae (Mygalomorphae plus Araneomorphae. We use the spidroin gene tree to reconstruct the evolution of amino acid

  15. Phylogenetic analysis reveals conservation and diversification of micro RNA166 genes among diverse plant species.

    Science.gov (United States)

    Barik, Suvakanta; SarkarDas, Shabari; Singh, Archita; Gautam, Vibhav; Kumar, Pramod; Majee, Manoj; Sarkar, Ananda K

    2014-01-01

    Similar to the majority of the microRNAs, mature miR166s are derived from multiple members of MIR166 genes (precursors) and regulate various aspects of plant development by negatively regulating their target genes (Class III HD-ZIP). The evolutionary conservation or functional diversification of miRNA166 family members remains elusive. Here, we show the phylogenetic relationships among MIR166 precursor and mature sequences from three diverse model plant species. Despite strong conservation, some mature miR166 sequences, such as ppt-miR166m, have undergone sequence variation. Critical sequence variation in ppt-miR166m has led to functional diversification, as it targets non-HD-ZIPIII gene transcript (s). MIR166 precursor sequences have diverged in a lineage specific manner, and both precursors and mature osa-miR166i/j are highly conserved. Interestingly, polycistronic MIR166s were present in Physcomitrella and Oryza but not in Arabidopsis. The nature of cis-regulatory motifs on the upstream promoter sequences of MIR166 genes indicates their possible contribution to the functional variation observed among miR166 species. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Molecular detection of TasA gene in endophytic Bacillus species ...

    African Journals Online (AJOL)

    Molecular detection of TasA gene in endophytic Bacillus species and characterization of the gene in Bacillus amyloliquefaciens. ... African Journal of Biotechnology ... in Bacillus amyloliquefaciens PEBA20 and 7 strains of Bacillus subtilis, ...

  17. Patterns of specificity and diversity in species of Paraorygmatobothrium Ruhnke, 1994 (Cestoda: Phyllobothriidae) in Moreton Bay, Queensland, Australia, with the description of four new species.

    Science.gov (United States)

    Cutmore, Scott C; Bennett, Michael B; Miller, Terrence L; Cribb, Thomas H

    2017-11-01

    A survey of tapeworms of galeomorph sharks from Moreton Bay (Queensland, Australia) identified a complex of species of Paraorygmatobothrium Ruhnke, 1994 infecting 11 carcharhiniform and two orectolobiform species. Combined morphological and multi-locus molecular analyses (based on the 28S nuclear ribosomal RNA and partial mitochondrial NADH dehydrogenase subunit 1 genes) revealed the presence of 12 species of Paraorygmatobothrium; four species (Paraorygmatobothrium christopheri n. sp., P. harti n. sp., P. sinclairtaylori n. sp. and P. ullmanni n. sp.) are considered to be new to science and are formally described, four represent known species, and four lack sufficient morphological data to allow definitive identification. In contrast to previous records for the genus, four of the species found in this study exhibited low host specificity [P. orectolobi (Butler, 1987) Ruhnke, 2011, P. sinclairtaylori, P. ullmanni and Paraorygmatobothrium sp. 3], three stenoxenic species were each found in two closely-related sharks (P. orectolobi, P. ullmanni and Paraorygmatobothrium sp. 3) and one euryxenic species was found in five species from two shark families (P. sinclairtaylori). One species was found to exhibit mild morphologically plasticity (P. orectolobi), with size range being associated with different shark species. Conversely, collections of almost morphologically indistinguishable specimens from single shark species were found to represent multiple species of Paraorygmatobothrium. The findings of this study indicate that the description of species of this genus on the basis of morphological data alone is problematic and that the inclusion of multi-locus molecular data is essential for future work on Paraorygmatobothrium. Host specificity, morphology and phylogenetic relatedness of species of Paraorygmatobothrium are explored.

  18. Targeted capture massively parallel sequencing analysis of LCIS and invasive lobular cancer: Repertoire of somatic genetic alterations and clonal relationships.

    Science.gov (United States)

    Sakr, Rita A; Schizas, Michail; Carniello, Jose V Scarpa; Ng, Charlotte K Y; Piscuoglio, Salvatore; Giri, Dilip; Andrade, Victor P; De Brot, Marina; Lim, Raymond S; Towers, Russell; Weigelt, Britta; Reis-Filho, Jorge S; King, Tari A

    2016-02-01

    Lobular carcinoma in situ (LCIS) has been proposed as a non-obligate precursor of invasive lobular carcinoma (ILC). Here we sought to define the repertoire of somatic genetic alterations in pure LCIS and in synchronous LCIS and ILC using targeted massively parallel sequencing. DNA samples extracted from microdissected LCIS, ILC and matched normal breast tissue or peripheral blood from 30 patients were subjected to massively parallel sequencing targeting all exons of 273 genes, including the genes most frequently mutated in breast cancer and DNA repair-related genes. Single nucleotide variants and insertions and deletions were identified using state-of-the-art bioinformatics approaches. The constellation of somatic mutations found in LCIS (n = 34) and ILC (n = 21) were similar, with the most frequently mutated genes being CDH1 (56% and 66%, respectively), PIK3CA (41% and 52%, respectively) and CBFB (12% and 19%, respectively). Among 19 LCIS and ILC synchronous pairs, 14 (74%) had at least one identical mutation in common, including identical PIK3CA and CDH1 mutations. Paired analysis of independent foci of LCIS from 3 breasts revealed at least one common mutation in each of the 3 pairs (CDH1, PIK3CA, CBFB and PKHD1L1). LCIS and ILC have a similar repertoire of somatic mutations, with PIK3CA and CDH1 being the most frequently mutated genes. The presence of identical mutations between LCIS-LCIS and LCIS-ILC pairs demonstrates that LCIS is a clonal neoplastic lesion, and provides additional evidence that at least some LCIS are non-obligate precursors of ILC. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  19. A new assay based on terminal restriction fragment length polymorphism of homocitrate synthase gene fragments for Candida species identification.

    Science.gov (United States)

    Szemiako, Kasjan; Śledzińska, Anna; Krawczyk, Beata

    2017-08-01

    Candida sp. have been responsible for an increasing number of infections, especially in patients with immunodeficiency. Species-specific differentiation of Candida sp. is difficult in routine diagnosis. This identification can have a highly significant association in therapy and prophylaxis. This work has shown a new application of the terminal restriction fragment length polymorphism (t-RFLP) method in the molecular identification of six species of Candida, which are the most common causes of fungal infections. Specific for fungi homocitrate synthase gene was chosen as a molecular target for amplification. The use of three restriction enzymes, DraI, RsaI, and BglII, for amplicon digestion can generate species-specific fluorescence labeled DNA fragment profiles, which can be used to determine the diagnostic algorithm. The designed method can be a cost-efficient high-throughput molecular technique for the identification of six clinically important Candida species.

  20. Physical linkage of a human immunoglobulin heavy chain variable region gene segment to diversity and joining region elements

    International Nuclear Information System (INIS)

    Schroeder, H.W. Jr.; Walter, M.A.; Hofker, M.H.; Ebens, A.; Van Dijk, K.W.; Liao, L.C.; Cox, D.W.; Milner, E.C.B.; Perlmutter, R.M.

    1988-01-01

    Antibody genes are assembled from a series of germ-line gene segments that are juxtaposed during the maturation of B lymphocytes. Although diversification of the adult antibody repertoire results in large part from the combinatorial joining of these gene segments, a restricted set of antibody heavy chain variable (V H ), diversity (D H ), and joining (J H ) region gene segments appears preferentially in the human fetal repertoire. The authors report here that one of these early-expressed V H elements (termed V H 6) is the most 3' V H gene segment, positioned 77 kilobases on the 5' side of the J H locus and immediately adjacent to a set of previously described D H sequences. In addition to providing a physical map linking human V H , D H , and J H elements, these results support the view that the programmed development of the antibody V H repertoire is determined in part by the chromosomal position of these gene segments

  1. Maintenance and Loss of Duplicated Genes by Dosage Subfunctionalization.

    Science.gov (United States)

    Gout, Jean-Francois; Lynch, Michael

    2015-08-01

    Whole-genome duplications (WGDs) have contributed to gene-repertoire enrichment in many eukaryotic lineages. However, most duplicated genes are eventually lost and it is still unclear why some duplicated genes are evolutionary successful whereas others quickly turn to pseudogenes. Here, we show that dosage constraints are major factors opposing post-WGD gene loss in several Paramecium species that share a common ancestral WGD. We propose a model where a majority of WGD-derived duplicates preserve their ancestral function and are retained to produce enough of the proteins performing this same ancestral function. Under this model, the expression level of individual duplicated genes can evolve neutrally as long as they maintain a roughly constant summed expression, and this allows random genetic drift toward uneven contributions of the two copies to total expression. Our analysis suggests that once a high level of imbalance is reached, which can require substantial lengths of time, the copy with the lowest expression level contributes a small enough fraction of the total expression that selection no longer opposes its loss. Extension of our analysis to yeast species sharing a common ancestral WGD yields similar results, suggesting that duplicated-gene retention for dosage constraints followed by divergence in expression level and eventual deterministic gene loss might be a universal feature of post-WGD evolution. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Global expression differences and tissue specific expression differences in rice evolution result in two contrasting types of differentially expressed genes

    KAUST Repository

    Horiuchi, Youko

    2015-12-23

    Background Since the development of transcriptome analysis systems, many expression evolution studies characterized evolutionary forces acting on gene expression, without explicit discrimination between global expression differences and tissue specific expression differences. However, different types of gene expression alteration should have different effects on an organism, the evolutionary forces that act on them might be different, and different types of genes might show different types of differential expression between species. To confirm this, we studied differentially expressed (DE) genes among closely related groups that have extensive gene expression atlases, and clarified characteristics of different types of DE genes including the identification of regulating loci for differential expression using expression quantitative loci (eQTL) analysis data. Results We detected differentially expressed (DE) genes between rice subspecies in five homologous tissues that were verified using japonica and indica transcriptome atlases in public databases. Using the transcriptome atlases, we classified DE genes into two types, global DE genes and changed-tissues DE genes. Global type DE genes were not expressed in any tissues in the atlas of one subspecies, however changed-tissues type DE genes were expressed in both subspecies with different tissue specificity. For the five tissues in the two japonica-indica combinations, 4.6 ± 0.8 and 5.9 ± 1.5 % of highly expressed genes were global and changed-tissues DE genes, respectively. Changed-tissues DE genes varied in number between tissues, increasing linearly with the abundance of tissue specifically expressed genes in the tissue. Molecular evolution of global DE genes was rapid, unlike that of changed-tissues DE genes. Based on gene ontology, global and changed-tissues DE genes were different, having no common GO terms. Expression differences of most global DE genes were regulated by cis-eQTLs. Expression

  3. Complete genome sequence of Brachyspira intermedia reveals unique genomic features in Brachyspira species and phage-mediated horizontal gene transfer

    Science.gov (United States)

    2011-01-01

    Background Brachyspira spp. colonize the intestines of some mammalian and avian species and show different degrees of enteropathogenicity. Brachyspira intermedia can cause production losses in chickens and strain PWS/AT now becomes the fourth genome to be completed in the genus Brachyspira. Results 15 classes of unique and shared genes were analyzed in B. intermedia, B. murdochii, B. hyodysenteriae and B. pilosicoli. The largest number of unique genes was found in B. intermedia and B. murdochii. This indicates the presence of larger pan-genomes. In general, hypothetical protein annotations are overrepresented among the unique genes. A 3.2 kb plasmid was found in B. intermedia strain PWS/AT. The plasmid was also present in the B. murdochii strain but not in nine other Brachyspira isolates. Within the Brachyspira genomes, genes had been translocated and also frequently switched between leading and lagging strands, a process that can be followed by different AT-skews in the third positions of synonymous codons. We also found evidence that bacteriophages were being remodeled and genes incorporated into them. Conclusions The accessory gene pool shapes species-specific traits. It is also influenced by reductive genome evolution and horizontal gene transfer. Gene-transfer events can cross both species and genus boundaries and bacteriophages appear to play an important role in this process. A mechanism for horizontal gene transfer appears to be gene translocations leading to remodeling of bacteriophages in combination with broad tropism. PMID:21816042

  4. The proximal first exon architecture of the murine ghrelin gene is highly similar to its human orthologue

    Directory of Open Access Journals (Sweden)

    Seim Inge

    2009-05-01

    Full Text Available Abstract Background The murine ghrelin gene (Ghrl, originally sequenced from stomach tissue, contains five exons and a single transcription start site in a short, 19 bp first exon (exon 0. We recently isolated several novel first exons of the human ghrelin gene and found evidence of a complex transcriptional repertoire. In this report, we examined the 5' exons of the murine ghrelin orthologue in a range of tissues using 5' RACE. Findings 5' RACE revealed two transcription start sites (TSSs in exon 0 and four TSSs in intron 0, which correspond to 5' extensions of exon 1. Using quantitative, real-time RT-PCR (qRT-PCR, we demonstrated that extended exon 1 containing Ghrl transcripts are largely confined to the spleen, adrenal gland, stomach, and skin. Conclusion We demonstrate that multiple transcription start sites are present in exon 0 and an extended exon 1 of the murine ghrelin gene, similar to the proximal first exon organisation of its human orthologue. The identification of several transcription start sites in intron 0 of mouse ghrelin (resulting in an extension of exon 1 raises the possibility that developmental-, cell- and tissue-specific Ghrl mRNA species are created by employing alternative promoters and further studies of the murine ghrelin gene are warranted.

  5. Fundamental characteristics of the immunoglobulin VH repertoire of chickens in comparison with those of humans, mice, and camelids.

    Science.gov (United States)

    Wu, Leeying; Oficjalska, Katarzyna; Lambert, Matthew; Fennell, Brian J; Darmanin-Sheehan, Alfredo; Ní Shúilleabháin, Deirdre; Autin, Bénédicte; Cummins, Emma; Tchistiakova, Lioudmila; Bloom, Laird; Paulsen, Janet; Gill, Davinder; Cunningham, Orla; Finlay, William J J

    2012-01-01

    Examination of 1269 unique naive chicken V(H) sequences showed that the majority of positions in the framework (FW) regions were maintained as germline, with high mutation rates observed in the CDRs. Many FW mutations could be clearly related to the modulation of CDR structure or the V(H)-V(L) interface. CDRs 1 and 2 of the V(H) exhibited frequent mutation in solvent-exposed positions, but conservation of common structural residues also found in human CDRs at the same positions. In comparison with humans and mice, the chicken CDR3 repertoire was skewed toward longer sequences, was dominated by small amino acids (G/S/A/C/T), and had higher cysteine (chicken, 9.4%; human, 1.6%; and mouse, 0.25%) but lower tyrosine content (chicken, 9.2%; human, 16.8%; and mouse 26.4%). A strong correlation (R(2) = 0.97) was observed between increasing CDR3 length and higher cysteine content. This suggests that noncanonical disulfides are strongly favored in chickens, potentially increasing CDR stability and complexity in the topology of the combining site. The probable formation of disulfide bonds between CDR3 and CDR1, FW2, or CDR2 was also observed, as described in camelids. All features of the naive repertoire were fully replicated in the target-selected, phage-displayed repertoire. The isolation of a chicken Fab with four noncanonical cysteines in the V(H) that exhibits 64 nM (K(D)) binding affinity for its target proved these constituents to be part of the humoral response, not artifacts. This study supports the hypothesis that disulfide bond-constrained CDR3s are a structural diversification strategy in the restricted germline v-gene repertoire of chickens.

  6. atpE gene as a new useful specific molecular target to quantify Mycobacterium in environmental samples

    Science.gov (United States)

    2013-01-01

    Background The environment is the likely source of many pathogenic mycobacterial species but detection of mycobacteria by bacteriological tools is generally difficult and time-consuming. Consequently, several molecular targets based on the sequences of housekeeping genes, non-functional RNA and structural ribosomal RNAs have been proposed for the detection and identification of mycobacteria in clinical or environmental samples. While certain of these targets were proposed as specific for this genus, most are prone to false positive results in complex environmental samples that include related, but distinct, bacterial genera. Nowadays the increased number of sequenced genomes and the availability of software for genomic comparison provide tools to develop novel, mycobacteria-specific targets, and the associated molecular probes and primers. Consequently, we conducted an in silico search for proteins exclusive to Mycobacterium spp. genomes in order to design sensitive and specific molecular targets. Results Among the 3989 predicted proteins from M. tuberculosis H37Rv, only 11 proteins showed 80% to 100% of similarity with Mycobacterium spp. genomes, and less than 50% of similarity with genomes of closely related Corynebacterium, Nocardia and Rhodococcus genera. Based on DNA sequence alignments, we designed primer pairs and a probe that specifically detect the atpE gene of mycobacteria, as verified by quantitative real-time PCR on a collection of mycobacteria and non-mycobacterial species. The real-time PCR method we developed was successfully used to detect mycobacteria in tap water and lake samples. Conclusions The results indicate that this real-time PCR method targeting the atpE gene can serve for highly specific detection and precise quantification of Mycobacterium spp. in environmental samples. PMID:24299240

  7. Gene-specific cell labeling using MiMIC transposons.

    Science.gov (United States)

    Gnerer, Joshua P; Venken, Koen J T; Dierick, Herman A

    2015-04-30

    Binary expression systems such as GAL4/UAS, LexA/LexAop and QF/QUAS have greatly enhanced the power of Drosophila as a model organism by allowing spatio-temporal manipulation of gene function as well as cell and neural circuit function. Tissue-specific expression of these heterologous transcription factors relies on random transposon integration near enhancers or promoters that drive the binary transcription factor embedded in the transposon. Alternatively, gene-specific promoter elements are directly fused to the binary factor within the transposon followed by random or site-specific integration. However, such insertions do not consistently recapitulate endogenous expression. We used Minos-Mediated Integration Cassette (MiMIC) transposons to convert host loci into reliable gene-specific binary effectors. MiMIC transposons allow recombinase-mediated cassette exchange to modify the transposon content. We developed novel exchange cassettes to convert coding intronic MiMIC insertions into gene-specific binary factor protein-traps. In addition, we expanded the set of binary factor exchange cassettes available for non-coding intronic MiMIC insertions. We show that binary factor conversions of different insertions in the same locus have indistinguishable expression patterns, suggesting that they reliably reflect endogenous gene expression. We show the efficacy and broad applicability of these new tools by dissecting the cellular expression patterns of the Drosophila serotonin receptor gene family. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  8. A novel Capsicum gene inhibits host-specific disease resistance to Phytophthora capsici.

    Science.gov (United States)

    Reeves, Gregory; Monroy-Barbosa, Ariadna; Bosland, Paul W

    2013-05-01

    A novel disease resistance inhibitor gene (inhibitor of P. capsici resistance [Ipcr]), found in the chile pepper (Capsicum annuum) variety 'New Mexico Capsicum Accession 10399' (NMCA10399), inhibits resistance to Phytophthora capsici but not to other species of Phytophthora. When a highly P. capsici-resistant variety was hybridized with NMCA10399, the resultant F1 populations, when screened, were completely susceptible to P. capsici for root rot and foliar blight disease syndromes, despite the dominance inheritance of P. capsici resistance in chile pepper. The F2 population displayed a 3:13 resistant-to-susceptible (R:S) ratio. The testcross population displayed a 1:1 R:S ratio, and a backcross population to NMCA10399 displayed complete susceptibility. These results demonstrate the presence of a single dominant inhibitor gene affecting P. capsici resistance in chile pepper. Moreover, when lines carrying the Ipcr gene were challenged against six Phytophthora spp., the nonhost resistance was not overcome. Therefore, the Ipcr gene is interfering with host-specific resistance but not the pathogen- or microbe-associated molecular pattern nonhost responses.

  9. Hox genes require homothorax and extradenticle for body wall identity specification but not for appendage identity specification during metamorphosis of Tribolium castaneum.

    Science.gov (United States)

    Smith, Frank W; Jockusch, Elizabeth L

    2014-11-01

    The establishment of segment identity is a key developmental process that allows for divergence along the anteroposterior body axis in arthropods. In Drosophila, the identity of a segment is determined by the complement of Hox genes it expresses. In many contexts, Hox transcription factors require the protein products of extradenticle (exd) and homothorax (hth) as cofactors to perform their identity specification functions. In holometabolous insects, segment identity may be specified twice, during embryogenesis and metamorphosis. To glean insight into the relationship between embryonic and metamorphic segmental identity specification, we have compared these processes in the flour beetle Tribolium castaneum, which develops ventral appendages during embryogenesis that later metamorphose into adult appendages with distinct morphologies. At metamorphosis, comparisons of RNAi phenotypes indicate that Hox genes function jointly with Tc-hth and Tc-exd to specify several region-specific aspects of the adult body wall. On the other hand, Hox genes specify appendage identities along the anteroposterior axis independently of Tc-hth/Tc-exd and Tc-hth/Tc-exd specify proximal vs. distal identity within appendages independently of Hox genes during this stage. During embryogenesis, Tc-hth and Tc-exd play a broad role in the segmentation process and are required for specification of body wall identities in the thorax; however, contrasting with results from other species, we did not obtain homeotic transformations of embryonic appendages in response to Tc-hth or Tc-exd RNAi. In general, the homeotic effects of interference with the function of Hox genes and Tc-hth/Tc-exd during metamorphosis did not match predictions based on embryonic roles of these genes. Comparing metamorphic patterning in T. castaneum to embryonic and post-embryonic development in hemimetabolous insects suggests that holometabolous metamorphosis combines patterning processes of both late embryogenesis and

  10. Impact of Bee Species and Plant Density on Alfalfa Pollination and Potential for Gene Flow

    Directory of Open Access Journals (Sweden)

    Johanne Brunet

    2010-01-01

    Full Text Available In outcrossing crops like alfalfa, various bee species can contribute to pollination and gene flow in seed production fields. With the increasing use of transgenic crops, it becomes important to determine the role of these distinct pollinators on alfalfa pollination and gene flow. The current study examines the relative contribution of honeybees, three bumble bee species, and three solitary bee species to pollination and gene flow in alfalfa. Two wild solitary bee species and one wild bumble bee species were best at tripping flowers, while the two managed pollinators commonly used in alfalfa seed production, honeybees and leaf cutting bees, had the lowest tripping rate. Honeybees had the greatest potential for gene flow and risk of transgene escape relative to the other pollinators. For honeybees, gene flow and risk of transgene escape were not affected by plant density although for the three bumble bee species gene flow and risk of transgene escape were the greatest in high-density fields.

  11. VDJtools: Unifying Post-analysis of T Cell Receptor Repertoires.

    Directory of Open Access Journals (Sweden)

    Mikhail Shugay

    2015-11-01

    Full Text Available Despite the growing number of immune repertoire sequencing studies, the field still lacks software for analysis and comprehension of this high-dimensional data. Here we report VDJtools, a complementary software suite that solves a wide range of T cell receptor (TCR repertoires post-analysis tasks, provides a detailed tabular output and publication-ready graphics, and is built on top of a flexible API. Using TCR datasets for a large cohort of unrelated healthy donors, twins, and multiple sclerosis patients we demonstrate that VDJtools greatly facilitates the analysis and leads to sound biological conclusions. VDJtools software and documentation are available at https://github.com/mikessh/vdjtools.

  12. Characterization of the hepcidin gene in eight species of bats.

    Science.gov (United States)

    Stasiak, Iga M; Smith, Dale A; Crawshaw, Graham J; Hammermueller, Jutta D; Bienzle, Dorothee; Lillie, Brandon N

    2014-02-01

    Hemochromatosis, or iron storage disease, has been associated with significant liver disease and mortality in captive Egyptian fruit bats (Rousettus aegyptiacus). The physiologic basis for this susceptibility has not been established. In humans, a deficiency or resistance to the iron regulatory hormone, hepcidin has been implicated in the development of hereditary hemochromatosis. In the present study, we compared the coding sequence of the hepcidin gene in eight species of bats representing three distinct taxonomic families with diverse life histories and dietary preferences. Bat hepcidin mRNA encoded a 23 amino acid signal peptide, a 34 or 35 amino acid pro-region, and a 25 amino acid mature peptide, similar to other mammalian species. Differences in the sequence of the portion of the hepcidin gene that encodes the mature peptide that might account for the increased susceptibility of the Egyptian fruit bat to iron storage disease were not identified. Variability in gene sequence corresponded to the taxonomic relationship amongst species. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. HIV-1 Vif's Capacity To Manipulate the Cell Cycle Is Species Specific.

    Science.gov (United States)

    Evans, Edward L; Becker, Jordan T; Fricke, Stephanie L; Patel, Kishan; Sherer, Nathan M

    2018-04-01

    Cells derived from mice and other rodents exhibit profound blocks to HIV-1 virion production, reflecting species-specific incompatibilities between viral Tat and Rev proteins and essential host factors cyclin T1 (CCNT1) and exportin-1 (XPO1, also known as CRM1), respectively. To determine if mouse cell blocks other than CCNT1 and XPO1 affect HIV's postintegration stages, we studied HIV-1 NL4-3 gene expression in mouse NIH 3T3 cells modified to constitutively express HIV-1-compatible versions of CCNT1 and XPO1 (3T3.CX cells). 3T3.CX cells supported both Rev-independent and Rev-dependent viral gene expression and produced relatively robust levels of virus particles, confirming that CCNT1 and XPO1 represent the predominant blocks to these stages. Unexpectedly, however, 3T3.CX cells were remarkably resistant to virus-induced cytopathic effects observed in human cell lines, which we mapped to the viral protein Vif and its apparent species-specific capacity to induce G 2 /M cell cycle arrest. Vif was able to mediate rapid degradation of human APOBEC3G and the PPP2R5D regulatory B56 subunit of the PP2A phosphatase holoenzyme in mouse cells, thus demonstrating that Vif NL4-3 's modulation of the cell cycle can be functionally uncoupled from some of its other defined roles in CUL5-dependent protein degradation. Vif was also unable to induce G 2 /M cell cycle arrest in other nonhuman cell types, including cells derived from nonhuman primates, leading us to propose that one or more human-specific cofactors underpin Vif's ability to modulate the cell cycle. IMPORTANCE Cells derived from mice and other rodents exhibit profound blocks to HIV-1 replication, thus hindering the development of a low-cost small-animal model for studying HIV/AIDS. Here, we engineered otherwise-nonpermissive mouse cells to express HIV-1-compatible versions of two species-specific host dependency factors, cyclin T1 (CCNT1) and exportin-1 (XPO1) (3T3.CX cells). We show that 3T3.CX cells rescue HIV-1

  14. Genome-wide analysis of Aux/IAA gene family in Solanaceae species using tomato as a model.

    Science.gov (United States)

    Wu, Jian; Peng, Zhen; Liu, Songyu; He, Yanjun; Cheng, Lin; Kong, Fuling; Wang, Jie; Lu, Gang

    2012-04-01

    Auxin plays key roles in a wide variety of plant activities, including embryo development, leaf formation, phototropism, fruit development and root initiation and development. Auxin/indoleacetic acid (Aux/IAA) genes, encoding short-lived nuclear proteins, are key regulators in the auxin transduction pathway. But how they work is still unknown. In order to conduct a systematic analysis of this gene family in Solanaceae species, a genome-wide search for the homologues of auxin response genes was carried out. Here, 26 and 27 non redundant AUX/IAAs were identified in tomato and potato, respectively. Using tomato as a model, a comprehensive overview of SlIAA gene family is presented, including the gene structures, phylogeny, chromosome locations, conserved motifs and cis-elements in promoter sequences. A phylogenetic tree generated from alignments of the predicted protein sequences of 31 OsIAAs, 29 AtIAAs, 31 ZmIAAs, and 26 SlIAAs revealed that these IAAs were clustered into three major groups and ten subgroups. Among them, seven subgroups were present in both monocot and dicot species, which indicated that the major functional diversification within the IAA family predated the monocot/dicot divergence. In contrast, group C and some other subgroups seemed to be species-specific. Quantitative real-time PCR (qRT-PCR) analysis showed that 19 of the 26 SlIAA genes could be detected in all tomato organs/tissues, however, seven of them were specifically expressed in some of tomato tissues. The transcript abundance of 17 SlIAA genes were increased within a few hours when the seedlings were treated with exogenous IAA. However, those of other six SlIAAs were decreased. The results of stress treatments showed that most SIIAA family genes responded to at least one of the three stress treatments, however, they exhibited diverse expression levels under different abiotic stress conditions in tomato seedlings. SlIAA20, SlIAA21 and SlIAA22 were not significantly influenced by stress

  15. High prevalence of abnormal motor repertoire at 3 months corrected age in extremely preterm infants.

    Science.gov (United States)

    Fjørtoft, Toril; Evensen, Kari Anne I; Øberg, Gunn Kristin; Songstad, Nils Thomas; Labori, Cathrine; Silberg, Inger Elisabeth; Loennecken, Marianne; Møinichen, Unn Inger; Vågen, Randi; Støen, Ragnhild; Adde, Lars

    2016-03-01

    To compare early motor repertoire between extremely preterm and term-born infants. An association between the motor repertoire and gestational age and birth weight was explored in extremely preterm infants without severe ultrasound abnormalities. In a multicentre study, the early motor repertoire of 82 infants born extremely preterm (ELGAN:<28 weeks) and/or with extremely low birth weight (ELBW:<1000 g) and 87 term-born infants were assessed by the "Assessment of Motor Repertoire - 2 to 5 Months" (AMR) which is part of Prechtl's "General Movement Assessment", at 12 weeks post-term age. Fidgety movements were classified as normal if present and abnormal if absent, sporadic or exaggerated. Concurrent motor repertoire was classified as normal if smooth and fluent and abnormal if monotonous, stiff, jerky and/or predominantly fast or slow. Eight-teen ELBW/ELGAN infants had abnormal fidgety movements (8 absent, 7 sporadic and 3 exaggerated fidgety movements) compared with 2 control infants (OR:12.0; 95%CI:2.7-53.4) and 46 ELBW/ELGAN infants had abnormal concurrent motor repertoire compared with 17 control infants (OR:5.3; 95%CI:2.6-10.5). Almost all detailed aspects of the AMR differed between the groups. Results were the same when three infants with severe ultrasound abnormalities were excluded. In the remaining ELBW/ELGAN infants, there was no association between motor repertoire and gestational age or birth weight. ELBW/ELGAN infants had poorer quality of early motor repertoire than term-born infants.The findings were not explained by severe abnormalities on neonatal ultrasound scans and were not correlated to the degree of prematurity. The consequences of these abnormal movement patterns remain to be seen in future follow-up studies. Copyright © 2015 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  16. TiGER: a database for tissue-specific gene expression and regulation.

    Science.gov (United States)

    Liu, Xiong; Yu, Xueping; Zack, Donald J; Zhu, Heng; Qian, Jiang

    2008-06-09

    Understanding how genes are expressed and regulated in different tissues is a fundamental and challenging question. However, most of currently available biological databases do not focus on tissue-specific gene regulation. The recent development of computational methods for tissue-specific combinational gene regulation, based on transcription factor binding sites, enables us to perform a large-scale analysis of tissue-specific gene regulation in human tissues. The results are stored in a web database called TiGER (Tissue-specific Gene Expression and Regulation). The database contains three types of data including tissue-specific gene expression profiles, combinatorial gene regulations, and cis-regulatory module (CRM) detections. At present the database contains expression profiles for 19,526 UniGene genes, combinatorial regulations for 7,341 transcription factor pairs and 6,232 putative CRMs for 2,130 RefSeq genes. We have developed and made publicly available a database, TiGER, which summarizes and provides large scale data sets for tissue-specific gene expression and regulation in a variety of human tissues. This resource is available at 1.

  17. TiGER: A database for tissue-specific gene expression and regulation

    Directory of Open Access Journals (Sweden)

    Zack Donald J

    2008-06-01

    Full Text Available Abstract Background Understanding how genes are expressed and regulated in different tissues is a fundamental and challenging question. However, most of currently available biological databases do not focus on tissue-specific gene regulation. Results The recent development of computational methods for tissue-specific combinational gene regulation, based on transcription factor binding sites, enables us to perform a large-scale analysis of tissue-specific gene regulation in human tissues. The results are stored in a web database called TiGER (Tissue-specific Gene Expression and Regulation. The database contains three types of data including tissue-specific gene expression profiles, combinatorial gene regulations, and cis-regulatory module (CRM detections. At present the database contains expression profiles for 19,526 UniGene genes, combinatorial regulations for 7,341 transcription factor pairs and 6,232 putative CRMs for 2,130 RefSeq genes. Conclusion We have developed and made publicly available a database, TiGER, which summarizes and provides large scale data sets for tissue-specific gene expression and regulation in a variety of human tissues. This resource is available at 1.

  18. Design of a species-specific PCR method for the detection of the heat-resistant fungi Talaromyces macrosporus and Talaromyces trachyspermus.

    Science.gov (United States)

    Yamashita, S; Nakagawa, H; Sakaguchi, T; Arima, T-H; Kikoku, Y

    2018-01-01

    Heat-resistant fungi occur sporadically and are a continuing problem for the food and beverage industry. The genus Talaromyces, as a typical fungus, is capable of producing the heat-resistant ascospores responsible for the spoilage of processed food products. Isocitrate lyase, a signature enzyme of the glyoxylate cycle, is required for the metabolism of non-fermentable carbon compounds, like acetate and ethanol. Here, species-specific primer sets for detection and identification of DNA derived from Talaromyces macrosporus and Talaromyces trachyspermus were designed based on the nucleotide sequences of their isocitrate lyase genes. Polymerase chain reaction (PCR) using a species-specific primer set amplified products specific to T. macrosporus and T. trachyspermus. Other fungal species, such as Byssochlamys fulva and Hamigera striata, which cause food spoilage, were not detected using the Talaromyces-specific primer sets. The detection limit for each species-specific primer set was determined as being 50 pg of template DNA, without using a nested PCR method. The specificity of each species-specific primer set was maintained in the presence of 1,000-fold amounts of genomic DNA from other fungi. The method also detected fungal DNA extracted from blueberry inoculated with T. macrosporus. This PCR method provides a quick, simple, powerful and reliable way to detect T. macrosporus and T. trachyspermus. Polymerase chain reaction (PCR)-based detection is rapid, convenient and sensitive compared with traditional methods of detecting heat-resistant fungi. In this study, a PCR-based method was developed for the detection and identification of amplification products from Talaromyces macrosporus and Talaromyces trachyspermus using primer sets that target the isocitrate lyase gene. This method could be used for the on-site detection of T. macrosporus and T. trachyspermus in the near future, and will be helpful in the safety control of raw materials and in food and beverage

  19. Genome-wide analysis of positively selected genes in seasonal and non-seasonal breeding species.

    Directory of Open Access Journals (Sweden)

    Yuhuan Meng

    Full Text Available Some mammals breed throughout the year, while others breed only at certain times of year. These differences in reproductive behavior can be explained by evolution. We identified positively-selected genes in two sets of species with different degrees of relatedness including seasonal and non-seasonal breeding species, using branch-site models. After stringent filtering by sum of pairs scoring, we revealed that more genes underwent positive selection in seasonal compared with non-seasonal breeding species. Positively-selected genes were verified by cDNA mapping of the positive sites with the corresponding cDNA sequences. The design of the evolutionary analysis can effectively lower the false-positive rate and thus identify valid positive genes. Validated, positively-selected genes, including CGA, DNAH1, INVS, and CD151, were related to reproductive behaviors such as spermatogenesis and cell proliferation in non-seasonal breeding species. Genes in seasonal breeding species, including THRAP3, TH1L, and CMTM6, may be related to the evolution of sperm and the circadian rhythm system. Identification of these positively-selected genes might help to identify the molecular mechanisms underlying seasonal and non-seasonal reproductive behaviors.

  20. Distinct cell-specific expression of homospermidine synthase involved in pyrrolizidine alkaloid biosynthesis in three species of the boraginales.

    Science.gov (United States)

    Niemüller, Daniel; Reimann, Andreas; Ober, Dietrich

    2012-07-01

    Homospermidine synthase (HSS) is the first specific enzyme in pyrrolizidine alkaloid (PA) biosynthesis, a pathway involved in the plant's chemical defense. HSS has been shown to be recruited repeatedly by duplication of a gene involved in primary metabolism. Within the lineage of the Boraginales, only one gene duplication event gave rise to HSS. Here, we demonstrate that the tissue-specific expression of HSS in three boraginaceous species, Heliotropium indicum, Symphytum officinale, and Cynoglossum officinale, is unique with respect to plant organ, tissue, and cell type. Within H. indicum, HSS is expressed exclusively in nonspecialized cells of the lower epidermis of young leaves and shoots. In S. officinale, HSS expression has been detected in the cells of the root endodermis and in leaves directly underneath developing inflorescences. In young roots of C. officinale, HSS is detected only in cells of the endodermis, but in a later developmental stage, additionally in the pericycle. The individual expression patterns are compared with those within the Senecioneae lineage (Asteraceae), where HSS expression is reproducibly found in specific cells of the endodermis and the adjacent cortex parenchyma of the roots. The individual expression patterns within the Boraginales species are discussed as being a requirement for the successful recruitment of HSS after gene duplication. The diversity of HSS expression within this lineage adds a further facet to the already diverse patterns of expression that have been observed for HSS in other PA-producing plant lineages, making this PA-specific enzyme one of the most diverse expressed proteins described in the literature.

  1. Automated analysis of high-throughput B-cell sequencing data reveals a high frequency of novel immunoglobulin V gene segment alleles.

    Science.gov (United States)

    Gadala-Maria, Daniel; Yaari, Gur; Uduman, Mohamed; Kleinstein, Steven H

    2015-02-24

    Individual variation in germline and expressed B-cell immunoglobulin (Ig) repertoires has been associated with aging, disease susceptibility, and differential response to infection and vaccination. Repertoire properties can now be studied at large-scale through next-generation sequencing of rearranged Ig genes. Accurate analysis of these repertoire-sequencing (Rep-Seq) data requires identifying the germline variable (V), diversity (D), and joining (J) gene segments used by each Ig sequence. Current V(D)J assignment methods work by aligning sequences to a database of known germline V(D)J segment alleles. However, existing databases are likely to be incomplete and novel polymorphisms are hard to differentiate from the frequent occurrence of somatic hypermutations in Ig sequences. Here we develop a Tool for Ig Genotype Elucidation via Rep-Seq (TIgGER). TIgGER analyzes mutation patterns in Rep-Seq data to identify novel V segment alleles, and also constructs a personalized germline database containing the specific set of alleles carried by a subject. This information is then used to improve the initial V segment assignments from existing tools, like IMGT/HighV-QUEST. The application of TIgGER to Rep-Seq data from seven subjects identified 11 novel V segment alleles, including at least one in every subject examined. These novel alleles constituted 13% of the total number of unique alleles in these subjects, and impacted 3% of V(D)J segment assignments. These results reinforce the highly polymorphic nature of human Ig V genes, and suggest that many novel alleles remain to be discovered. The integration of TIgGER into Rep-Seq processing pipelines will increase the accuracy of V segment assignments, thus improving B-cell repertoire analyses.

  2. Cross-species multiple environmental stress responses: An integrated approach to identify candidate genes for multiple stress tolerance in sorghum (Sorghum bicolor (L. Moench and related model species.

    Directory of Open Access Journals (Sweden)

    Adugna Abdi Woldesemayat

    associated with different traits that are responsive to multiple stresses. Ontology mapping was used to validate the identified genes, while reconstruction of the phylogenetic tree was instrumental to infer the evolutionary relationship of the sorghum orthologs. The results also show specific genes responsible for various interrelated components of drought response mechanism such as drought tolerance, drought avoidance and drought escape.We submit that this approach is novel and to our knowledge, has not been used previously in any other research; it enables us to perform cross-species queries for genes that are likely to be associated with multiple stress tolerance, as a means to identify novel targets for engineering stress resistance in sorghum and possibly, in other crop species.

  3. Mitochondrial 16S ribosomal RNA gene for forensic identification of crocodile species.

    Science.gov (United States)

    Naga Jogayya, K; Meganathan, P R; Dubey, Bhawna; Haque, I

    2013-05-01

    All crocodilians are under various threats due to over exploitation and these species have been listed in Appendix I or II of CITES. Lack of molecular techniques for the forensic identification of confiscated samples makes it difficult to enforce the law. Therefore, we herein present a molecular method developed on the basis on 16S rRNA gene of mitochondrial DNA for identification of crocodile species. We have developed a set of 16S rRNA primers for PCR based identification of crocodilian species. These novel primers amplify partial 16S rRNA sequences of six crocodile species which can be later combined to obtain a larger region (1290 bp) of 16S rRNA gene. This 16S rRNA gene could be used as an effective tool for forensic authentication of crocodiles. The described primers hold great promise in forensic identification of crocodile species, which can aid in the effective enforcement of law and conservation of these species. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  4. A meta-analysis based method for prioritizing candidate genes involved in a pre-specific function

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    Jingjing Zhai

    2016-12-01

    Full Text Available The identification of genes associated with a given biological function in plants remains a challenge, although network-based gene prioritization algorithms have been developed for Arabidopsis thaliana and many non-model plant species. Nevertheless, these network-based gene prioritization algorithms have encountered several problems; one in particular is that of unsatisfactory prediction accuracy due to limited network coverage, varying link quality, and/or uncertain network connectivity. Thus a model that integrates complementary biological data may be expected to increase the prediction accuracy of gene prioritization. Towards this goal, we developed a novel gene prioritization method named RafSee, to rank candidate genes using a random forest algorithm that integrates sequence, evolutionary, and epigenetic features of plants. Subsequently, we proposed an integrative approach named RAP (Rank Aggregation-based data fusion for gene Prioritization, in which an order statistics-based meta-analysis was used to aggregate the rank of the network-based gene prioritization method and RafSee, for accurately prioritizing candidate genes involved in a pre-specific biological function. Finally, we showcased the utility of RAP by prioritizing 380 flowering-time genes in Arabidopsis. The ‘leave-one-out’ cross-validation experiment showed that RafSee could work as a complement to a current state-of-art network-based gene prioritization system (AraNet v2. Moreover, RAP ranked 53.68% (204/380 flowering-time genes higher than AraNet v2, resulting in an 39.46% improvement in term of the first quartile rank. Further evaluations also showed that RAP was effective in prioritizing genes-related to different abiotic stresses. To enhance the usability of RAP for Arabidopsis and non-model plant species, an R package implementing the method is freely available at http://bioinfo.nwafu.edu.cn/software.

  5. Analysis of 16S rRNA and mxaF genes revealing insights into Methylobacterium niche-specific plant association

    Science.gov (United States)

    Dourado, Manuella Nóbrega; Andreote, Fernando Dini; Dini-Andreote, Francisco; Conti, Raphael; Araújo, Janete Magali; Araújo, Welington Luiz

    2012-01-01

    The genus Methylobacterium comprises pink-pigmented facultative methylotrophic (PPFM) bacteria, known to be an important plant-associated bacterial group. Species of this group, described as plant-nodulating, have the dual capacity of producing cytokinin and enzymes, such as pectinase and cellulase, involved in systemic resistance induction and nitrogen fixation under specific plant environmental conditions. The aim hereby was to evaluate the phylogenetic distribution of Methylobacterium spp. isolates from different host plants. Thus, a comparative analysis between sequences from structural (16S rRNA) and functional mxaF (which codifies for a subunit of the enzyme methanol dehydrogenase) ubiquitous genes, was undertaken. Notably, some Methylobacterium spp. isolates are generalists through colonizing more than one host plant, whereas others are exclusively found in certain specific plant-species. Congruency between phylogeny and specific host inhabitance was higher in the mxaF gene than in the 16S rRNA, a possible indication of function-based selection in this niche. Therefore, in a first stage, plant colonization by Methylobacterium spp. could represent generalist behavior, possibly related to microbial competition and adaptation to a plant environment. Otherwise, niche-specific colonization is apparently impelled by the host plant. PMID:22481887

  6. Analysis of 16S rRNA and mxaF genes reveling insights into Methylobacterium niche-specific plant association

    Directory of Open Access Journals (Sweden)

    Manuella Nóbrega Dourado

    2012-01-01

    Full Text Available The genus Methylobacterium comprises pink-pigmented facultative methylotrophic (PPFM bacteria, known to be an important plant-associated bacterial group. Species of this group, described as plant-nodulating, have the dual capacity of producing cytokinin and enzymes, such as pectinase and cellulase, involved in systemic resistance induction and nitrogen fixation under specific plant environmental conditions. The aim hereby was to evaluate the phylogenetic distribution of Methylobacterium spp. isolates from different host plants. Thus, a comparative analysis between sequences from structural (16S rRNA and functional mxaF (which codifies for a subunit of the enzyme methanol dehydrogenase ubiquitous genes, was undertaken. Notably, some Methylobacterium spp. isolates are generalists through colonizing more than one host plant, whereas others are exclusively found in certain specific plant-species. Congruency between phylogeny and specific host inhabitance was higher in the mxaF gene than in the 16S rRNA, a possible indication of function-based selection in this niche. Therefore, in a first stage, plant colonization by Methylobacterium spp. could represent generalist behavior, possibly related to microbial competition and adaptation to a plant environment. Otherwise, niche-specific colonization is apparently impelled by the host plant.

  7. Analysis of 16S rRNA and mxaF genes revealing insights into Methylobacterium niche-specific plant association.

    Science.gov (United States)

    Dourado, Manuella Nóbrega; Andreote, Fernando Dini; Dini-Andreote, Francisco; Conti, Raphael; Araújo, Janete Magali; Araújo, Welington Luiz

    2012-01-01

    The genus Methylobacterium comprises pink-pigmented facultative methylotrophic (PPFM) bacteria, known to be an important plant-associated bacterial group. Species of this group, described as plant-nodulating, have the dual capacity of producing cytokinin and enzymes, such as pectinase and cellulase, involved in systemic resistance induction and nitrogen fixation under specific plant environmental conditions. The aim hereby was to evaluate the phylogenetic distribution of Methylobacterium spp. isolates from different host plants. Thus, a comparative analysis between sequences from structural (16S rRNA) and functional mxaF (which codifies for a subunit of the enzyme methanol dehydrogenase) ubiquitous genes, was undertaken. Notably, some Methylobacterium spp. isolates are generalists through colonizing more than one host plant, whereas others are exclusively found in certain specific plant-species. Congruency between phylogeny and specific host inhabitance was higher in the mxaF gene than in the 16S rRNA, a possible indication of function-based selection in this niche. Therefore, in a first stage, plant colonization by Methylobacterium spp. could represent generalist behavior, possibly related to microbial competition and adaptation to a plant environment. Otherwise, niche-specific colonization is apparently impelled by the host plant.

  8. Species-Specific Monoclonal Antibodies to Escherichia coli-Expressed p36 Cytosolic Protein of Mycoplasma hyopneumoniae

    Science.gov (United States)

    Caron, J.; Sawyer, N.; Moumen, B. Ben Abdel; Bouh, K. Cheikh Saad; Dea, S.

    2000-01-01

    The p36 protein of Mycoplasma hyopneumoniae is a cytosolic protein carrying species-specific antigenic determinants. Based on the genomic sequence of the reference strain ATCC 25934, primers were designed for PCR amplification of the p36-encoding gene (948 bp). These primers were shown to be specific to M. hyopneumoniae since no DNA amplicons could be obtained with other mycoplasma species and pathogenic bacteria that commonly colonize the porcine respiratory tract. The amplified p36 gene was subcloned into the pGEX-4T-1 vector to be expressed in Escherichia coli as a fusion protein with glutathione S-transferase (GST). The GST-p36 recombinant fusion protein was purified by affinity chromatography and cut by thrombin, and the enriched p36 protein was used to immunize female BALB/c mice for the production of anti-p36 monoclonal antibodies (MAbs). The polypeptide specificity of the nine MAbs obtained was confirmed by Western immunoblotting with cell lysates prepared from the homologous strain. Cross-reactivity studies of the anti-p36 MAbs towards two other M. hyopneumoniae reference strains (ATCC 25095 and J strains) and Quebec field strains that had been isolated in culture suggested that these anti-p36 MAbs were directed against a highly conserved epitope, or closely located epitopes, of the p36 protein. No reactivity was demonstrated against other mycoplasma species tested. Clinical signs and lesions suggestive of enzootic pneumonia were reproduced in specific-pathogen-free pigs infected experimentally with a virulent Quebec field strain (IAF-DM9827) of M. hyopneumoniae. The bacteria could be recovered from lung homogenates of pigs that were killed after the 3-week observation period by both PCR and cultivation procedures. Furthermore, the anti-p36 MAbs permitted effective detection by indirect immunofluorescence of M. hyopneumoniae in frozen lung sections from experimentally infected pigs. However, attempts to use the recombinant p36 protein as an antigen in an

  9. Malazy, a degenerate, species-specific transposable element in Cercospora zeae-maydis.

    Science.gov (United States)

    Shim, Won-Bo; Dunkle, Larry D

    2005-01-01

    Two fungal pathogens, Cercospora zeae-maydis Groups I and II, cause gray leaf spot of maize. During the sequencing of a cosmid library from C. zeae-maydis Group I, we discovered a sequence with high similarity to Maggy, a transposable element from Magnaporthe grisea. The element from C. zeae-maydis, named Malazy, contained 194-base-pair terminal repeats and sequences with high similarity to reverse transcriptase and integrase, components of the POL gene in the gypsy-like retrotransposons in fungi. Sequences with similarity to other POL gene components, protease and ribonuclease, were not detected in Malazy. A single copy of the element was detected by PCR and Southern analyses in all six North American isolates of C. zeae-maydis Group I but was not detected in the four isolates of C. zeae-maydis Group II from three continents or in phylogenetically related species. Fragments of the core domains of reverse transcriptase and integrase contained a high frequency of stop codons that were conserved in all six isolates of Group I. Additional C:G to T:A transitions in occasional isolates usually were silent mutations, while two resulted in isolate-specific stop codons. The absence of Malazy from related species suggests that it was acquired after the divergence of C. zeae-maydis Groups I and II. The high frequency of stop codons and the presence of a single copy of the element suggest that it was inactivated soon after it was acquired. Because the element is inactive and because reading frames for other genes were not found in sequences flanking the element, Malazy does not appear to be the cause of differences leading to speciation or genetic diversity between C. zeae-maydis Groups I and II.

  10. [Phylogenetic analysis of closely related Leuconostoc citreum species based on partial housekeeping genes].

    Science.gov (United States)

    Lv, Qiang; Chen, Ming; Xu, Haiyan; Song, Yuqin; Sun, Zhihong; Dan, Tong; Sun, Tiansong

    2013-07-04

    Using the 16S rRNA, dnaA, murC and pyrG gene sequences, we identified the phylogenetic relationship among closely related Leuconostoc citreum species. Seven Leu. citreum strains originally isolated from sourdough were characterized by PCR methods to amplify the dnaA, murC and pyrG gene sequences, which were determined to assess the suitability as phylogenetic markers. Then, we estimated the genetic distance and constructed the phylogenetic trees including 16S rRNA and above mentioned three housekeeping genes combining with published corresponding sequences. By comparing the phylogenetic trees, the topology of three housekeeping genes trees were consistent with that of 16S rRNA gene. The homology of closely related Leu. citreum species among dnaA, murC, pyrG and 16S rRNA gene sequences were different, ranged from75.5% to 97.2%, 50.2% to 99.7%, 65.0% to 99.8% and 98.5% 100%, respectively. The phylogenetic relationship of three housekeeping genes sequences were highly consistent with the results of 16S rRNA gene sequence, while the genetic distance of these housekeeping genes were extremely high than 16S rRNA gene. Consequently, the dnaA, murC and pyrG gene are suitable for classification and identification closely related Leu. citreum species.

  11. Identification of Photosynthesis-Associated C4 Candidate Genes through Comparative Leaf Gradient Transcriptome in Multiple Lineages of C3 and C4 Species

    Science.gov (United States)

    Ding, Zehong; Weissmann, Sarit; Wang, Minghui; Du, Baijuan; Huang, Lei; Wang, Lin; Tu, Xiaoyu; Zhong, Silin; Myers, Christopher; Brutnell, Thomas P.; Sun, Qi; Li, Pinghua

    2015-01-01

    Leaves of C4 crops usually have higher radiation, water and nitrogen use efficiencies compared to the C3 species. Engineering C4 traits into C3 crops has been proposed as one of the most promising ways to repeal the biomass yield ceiling. To better understand the function of C4 photosynthesis, and to identify candidate genes that are associated with the C4 pathways, a comparative transcription network analysis was conducted on leaf developmental gradients of three C4 species including maize, green foxtail and sorghum and one C3 species, rice. By combining the methods of gene co-expression and differentially co-expression networks, we identified a total of 128 C4 specific genes. Besides the classic C4 shuttle genes, a new set of genes associated with light reaction, starch and sucrose metabolism, metabolites transportation, as well as transcription regulation, were identified as involved in C4 photosynthesis. These findings will provide important insights into the differential gene regulation between C3 and C4 species, and a good genetic resource for establishing C4 pathways in C3 crops. PMID:26465154

  12. Identification of Photosynthesis-Associated C4 Candidate Genes through Comparative Leaf Gradient Transcriptome in Multiple Lineages of C3 and C4 Species.

    Science.gov (United States)

    Ding, Zehong; Weissmann, Sarit; Wang, Minghui; Du, Baijuan; Huang, Lei; Wang, Lin; Tu, Xiaoyu; Zhong, Silin; Myers, Christopher; Brutnell, Thomas P; Sun, Qi; Li, Pinghua

    2015-01-01

    Leaves of C4 crops usually have higher radiation, water and nitrogen use efficiencies compared to the C3 species. Engineering C4 traits into C3 crops has been proposed as one of the most promising ways to repeal the biomass yield ceiling. To better understand the function of C4 photosynthesis, and to identify candidate genes that are associated with the C4 pathways, a comparative transcription network analysis was conducted on leaf developmental gradients of three C4 species including maize, green foxtail and sorghum and one C3 species, rice. By combining the methods of gene co-expression and differentially co-expression networks, we identified a total of 128 C4 specific genes. Besides the classic C4 shuttle genes, a new set of genes associated with light reaction, starch and sucrose metabolism, metabolites transportation, as well as transcription regulation, were identified as involved in C4 photosynthesis. These findings will provide important insights into the differential gene regulation between C3 and C4 species, and a good genetic resource for establishing C4 pathways in C3 crops.

  13. Identification of Photosynthesis-Associated C4 Candidate Genes through Comparative Leaf Gradient Transcriptome in Multiple Lineages of C3 and C4 Species.

    Directory of Open Access Journals (Sweden)

    Zehong Ding

    Full Text Available Leaves of C4 crops usually have higher radiation, water and nitrogen use efficiencies compared to the C3 species. Engineering C4 traits into C3 crops has been proposed as one of the most promising ways to repeal the biomass yield ceiling. To better understand the function of C4 photosynthesis, and to identify candidate genes that are associated with the C4 pathways, a comparative transcription network analysis was conducted on leaf developmental gradients of three C4 species including maize, green foxtail and sorghum and one C3 species, rice. By combining the methods of gene co-expression and differentially co-expression networks, we identified a total of 128 C4 specific genes. Besides the classic C4 shuttle genes, a new set of genes associated with light reaction, starch and sucrose metabolism, metabolites transportation, as well as transcription regulation, were identified as involved in C4 photosynthesis. These findings will provide important insights into the differential gene regulation between C3 and C4 species, and a good genetic resource for establishing C4 pathways in C3 crops.

  14. Large scale gene expression meta-analysis reveals tissue-specific, sex-biased gene expression in humans

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    Benjamin Mayne

    2016-10-01

    Full Text Available The severity and prevalence of many diseases are known to differ between the sexes. Organ specific sex-biased gene expression may underpin these and other sexually dimorphic traits. To further our understanding of sex differences in transcriptional regulation, we performed meta-analyses of sex biased gene expression in multiple human tissues. We analysed 22 publicly available human gene expression microarray data sets including over 2500 samples from 15 different tissues and 9 different organs. Briefly, by using an inverse-variance method we determined the effect size difference of gene expression between males and females. We found the greatest sex differences in gene expression in the brain, specifically in the anterior cingulate cortex, (1818 genes, followed by the heart (375 genes, kidney (224 genes, colon (218 genes and thyroid (163 genes. More interestingly, we found different parts of the brain with varying numbers and identity of sex-biased genes, indicating that specific cortical regions may influence sexually dimorphic traits. The majority of sex-biased genes in other tissues such as the bladder, liver, lungs and pancreas were on the sex chromosomes or involved in sex hormone production. On average in each tissue, 32% of autosomal genes that were expressed in a sex-biased fashion contained androgen or estrogen hormone response elements. Interestingly, across all tissues, we found approximately two-thirds of autosomal genes that were sex-biased were not under direct influence of sex hormones. To our knowledge this is the largest analysis of sex-biased gene expression in human tissues to date. We identified many sex-biased genes that were not under the direct influence of sex chromosome genes or sex hormones. These may provide targets for future development of sex-specific treatments for diseases.

  15. The peripheral NK cell repertoire after kidney transplantation is modulated by different immunosuppressive drugs

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    Christine eNeudoerfl

    2013-02-01

    Full Text Available In the context of kidney transplantation, little is known about the involvement of NK cells in the immune reaction leading to either rejection or immunological tolerance under immunosuppression. Therefore, the peripheral NK cell repertoire of patients after kidney transplantation was investigated in order to identify NK cell subsets that may be associated with the individual immune status at the time of their protocol biopsies for histopathological evaluation of the graft. Alterations in the peripheral NK cell repertoire could be correlated to the type of immunosuppression, i.e. calcineurin-inhibitors like CyclosporinA vs. Tacrolimus with or without addition of mTOR inhibitors. Here, we could demonstrate that the NK cell repertoire in peripheral blood of kidney transplant patients differs significantly from healthy individuals. The presence of donor-specific antibodies was associated with reduced numbers of CD56dim NK cells. Moreover, in patients, down-modulation of CD16 and CD6 on CD56dim NK cells was observed with significant differences between CyclosporinA- and Tac-treated patients. Tac-treatment was associated with decreased CD69, HLA-DR and increased CD94/NKG2A expression in CD56dim NK cells indicating that the quality of the immunosuppressive treatment impinges on the peripheral NK cell repertoire. In vitro studies with PBMC of healthy donors showed that this modulation of CD16, CD6, CD69, and HLA-DR could also be induced experimentally. The presence of calcineurin or mTOR inhibitors had also functional consequences regarding degranulation and IFN--production against K562 target cells, respectively. In summary, we postulate that the NK cell composition in peripheral blood of kidney transplanted patients represents an important hallmark of the efficacy of immunosuppression and may be even informative for the immune status after transplantation in terms of rejection vs. drug-induced allograft tolerance. Thus,NK cells can serve as sensors

  16. Exploring the potential relevance of human-specific genes to complex disease

    Directory of Open Access Journals (Sweden)

    Cooper David N

    2011-01-01

    Full Text Available Abstract Although human disease genes generally tend to be evolutionarily more ancient than non-disease genes, complex disease genes appear to be represented more frequently than Mendelian disease genes among genes of more recent evolutionary origin. It is therefore proposed that the analysis of human-specific genes might provide new insights into the genetics of complex disease. Cross-comparison with the Human Gene Mutation Database (http://www.hgmd.org revealed a number of examples of disease-causing and disease-associated mutations in putatively human-specific genes. A sizeable proportion of these were missense polymorphisms associated with complex disease. Since both human-specific genes and genes associated with complex disease have often experienced particularly rapid rates of evolutionary change, either due to weaker purifying selection or positive selection, it is proposed that a significant number of human-specific genes may play a role in complex disease.

  17. Teat apex colonization with coagulase-negative Staphylococcus species before parturition: Distribution and species-specific risk factors.

    Science.gov (United States)

    De Visscher, A; Piepers, S; Haesebrouck, F; De Vliegher, S

    2016-02-01

    Coagulase-negative staphylococci (CNS) are the main cause of bovine intramammary infections and are also abundantly present in extramammary habitats such as teat apices. Teat apex colonization (TAC) with CNS has already been explored in lactating dairy cows at the species level, whereas this is not true for dry cows and end-term heifers. Therefore, the aim of this observational study was to describe CNS TAC in nonlactating dairy cows and end-term heifers in Flemish dairy herds and to identify associated risk factors at the herd, cow, and quarter level. All CNS were molecularly identified to the species level using transfer RNA intergenic spacer PCR (tDNA-PCR) and sequencing of the 16S rRNA gene, allowing for species-specific statistical analyses using multivariable, multilevel logistic regression. Staphylococcus devriesei, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus equorum were the most frequently isolated species. Staphylococcus chromogenes was the sole species colonizing teat apices of cows and heifers in all herds, whereas large between-herd differences were observed for the other species. Teat apices of red and white Holstein Friesians, of quarters dried off without an internal teat sealer, and swabbed in months with lower precipitation and higher ambient temperature were significantly more likely to be colonized by S. devriesei. Slightly dirty teat apices and teat apices swabbed in months with lower precipitation had higher odds of being colonized by S. chromogenes, whereas teat apices sampled in months with lower precipitation and higher ambient temperature were more likely to be colonized by S. haemolyticus. Dirty teat apices and teat apices swabbed in months with lower ambient temperature in combination with low precipitation had higher odds of being colonized by S. equorum. Diverse factors explaining CNS TAC, yet mostly related to humidity, ambient temperature, and hygiene, substantiate differences in epidemiological

  18. Tissue-specific functional networks for prioritizing phenotype and disease genes.

    Directory of Open Access Journals (Sweden)

    Yuanfang Guan

    Full Text Available Integrated analyses of functional genomics data have enormous potential for identifying phenotype-associated genes. Tissue-specificity is an important aspect of many genetic diseases, reflecting the potentially different roles of proteins and pathways in diverse cell lineages. Accounting for tissue specificity in global integration of functional genomics data is challenging, as "functionality" and "functional relationships" are often not resolved for specific tissue types. We address this challenge by generating tissue-specific functional networks, which can effectively represent the diversity of protein function for more accurate identification of phenotype-associated genes in the laboratory mouse. Specifically, we created 107 tissue-specific functional relationship networks through integration of genomic data utilizing knowledge of tissue-specific gene expression patterns. Cross-network comparison revealed significantly changed genes enriched for functions related to specific tissue development. We then utilized these tissue-specific networks to predict genes associated with different phenotypes. Our results demonstrate that prediction performance is significantly improved through using the tissue-specific networks as compared to the global functional network. We used a testis-specific functional relationship network to predict genes associated with male fertility and spermatogenesis phenotypes, and experimentally confirmed one top prediction, Mbyl1. We then focused on a less-common genetic disease, ataxia, and identified candidates uniquely predicted by the cerebellum network, which are supported by both literature and experimental evidence. Our systems-level, tissue-specific scheme advances over traditional global integration and analyses and establishes a prototype to address the tissue-specific effects of genetic perturbations, diseases and drugs.

  19. Organization and Biology of the Porcine Serum Amyloid A (SAA) Gene Cluster: Isoform Specific Responses to Bacterial Infection

    DEFF Research Database (Denmark)

    Olsen, Helle G; Skovgaard, Kerstin; Nielsen, Ole L

    2013-01-01

    Serum amyloid A (SAA) is a prominent acute phase protein. Although its biological functions are debated, the wide species distribution of highly homologous SAA proteins and their uniform behavior in response to injury or inflammation in itself suggests a significant role for this protein. The pig...... is increasingly being used as a model for the study of inflammatory reactions, yet only little is known about how specific SAA genes are regulated in the pig during acute phase responses and other responses induced by pro-inflammatory host mediators. We designed SAA gene specific primers and quantified the gene...... expression of porcine SAA1, SAA2, SAA3, and SAA4 by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in liver, spleen, and lung tissue from pigs experimentally infected with the Gram-negative swine specific bacterium Actinobacillus pleuropneumoniae, as well as from pigs experimentally...

  20. Negotiation over self-control and activity: an analysis of balancing in the repertoires of Finnish healthy lifestyles.

    Science.gov (United States)

    Pajari, Pia M; Jallinoja, Piia; Absetz, Pilvikki

    2006-05-01

    This study analyses arguments for and against the notion of healthy lifestyles, and the construction of responsibility for health, in group discussions in Finland. With data from four focus groups, we identified five interpretative repertoires: a strong activity repertoire reflects the dominant cultural value of health and emphasizes self-control. Three other repertoires--illness, external barriers, and weak character--share the underlying values of the activity repertoire, but exemplify situations where the individual lacks control, seeking to justify deviations from the norm of activity. One counter-repertoire, the pleasure repertoire, questions the hegemonic value of health, and discusses other competing values. The discussion of health is an ongoing dialectical process drawing from the different repertoires. In order to avoid stigmatization and to save face in the social situation of a focus group, the subjects strive to balance their accounts of behaviours considered unhealthy by also claiming healthy behaviours. They also strike a balance between extreme rigidity and carelessness, emphasizing the ideal of moderation and harmony. The findings point to a need to consider variations in and underpinnings of a "good life" at the individual level. Encouraging people to specify the meaning and content of moderation in their personal lives could provide a new perspective for health education and health promotion.

  1. A Novel Complementation Assay for Quick and Specific Screen of Genes Encoding Glycerol-3-Phosphate Acyltransferases

    Directory of Open Access Journals (Sweden)

    Jie Lei

    2018-03-01

    Full Text Available The initial step in glycerolipid biosynthesis, especially in diverse allopolyploid crop species, is poorly understood, mainly due to the lack of an effective and convenient method for functional characterization of genes encoding glycerol-3-phosphate acyltransferases (GPATs catalyzing this reaction. Here we present a novel complementation assay for quick and specific characterization of GPAT-encoding genes. Its key design involves rational construction of yeast conditional lethal gat1Δgat2Δ double mutant bearing the heterologous Arabidopsis AtGPAT1 gene whose leaky expression under repressed conditions does not support any non-specific growth, thereby circumventing the false positive problem encountered with the system based on the gat1Δgat2Δ mutant harboring the native episomal GAT1 gene whose leaky expression appears to be sufficient for generating enough GPAT activities for the non-specific restoration of the mutant growth. A complementation assay developed based on this novel mutant enables quick phenotypic screen of GPAT sequences. A high degree of specificity of our assay was exemplified by its ability to differentiate effectively GPAT-encoding genes from those of other fatty acyltransferases and lipid-related sequences. Using this assay, we show that Arabidopsis AtGPAT1, AtGPAT5, and AtGPAT7 can complement the phosphatidate biosynthetic defect in the double mutants. Collectively, our assay provides a powerful tool for rapid screening, validation and optimization of GPAT sequences, aiding future engineering of the initial step of the triacylglycerol biosynthesis in oilseeds.

  2. Sexual isolation between Drosophila melanogaster, D. simulans and D. mauritiana: sex and species specific discrimination.

    Science.gov (United States)

    Carracedo, M C; Suarez, C; Casares, P

    2000-01-01

    The sexual isolation among the related species Drosophila melanogaster, D. simulans and D. mauritiana is asymmetrical. While D. mauritiana males mate well with both D. melanogaster and D. simulans females, females of D. mauritiana discriminate strongly against males of these two species. Similarly, D. simulans males mate with D. melanogaster females but the reciprocal cross is difficult. Interspecific crosses between several populations of the three species were performed to determine if (i) males and females of the same species share a common sexual isolation genetic system, and (ii) males (or females) use the same genetic system to discriminate against females (or males) of the other two species. Results indicate that although differences in male and female isolation depend on the populations tested, the isolation behaviour between a pair of species is highly correlated despite the variations. However, the rank order of the isolation level along the populations was not correlated in both sexes, which suggests that different genes act in male and female sexual isolation. Neither for males nor for females, the isolation behaviour of one species was paralleled in the other two species, which indicates that the genetic systems involved in this trait are species-pair specific. The implications of these results are discussed.

  3. Friendship Repertoires and Care Arrangement: A Praxeological Approach.

    Science.gov (United States)

    Hahmann, Julia

    2017-01-01

    Friends are important companions and serve as sources for diverse dimensions of social support, including elderly care. Rather than researching populations that have already established care arrangements including friends, the author seeks to understand relationship systems with a focus on the inner logic friendship to consequently describe and understand involved care arrangements, be it with family members or friends. To illustrate the diversity of friendship repertoires, qualitative interviews with older adult Germans are analyzed regarding cognitive concepts of friendships in contrast to familiar ties as well as social practices around relationship systems. While some repertoires successfully include chosen ties in their care arrangements, others not only focus on family, they do not wish to receive care from friends. The article's praxeological approach highlights the need to reflect habitual differences when thinking about elderly informal care arrangements. © The Author(s) 2016.

  4. A Gene Family Coding for Salivary Proteins (SHOT) of the Polyphagous Spider Mite Tetranychus urticae Exhibits Fast Host-Dependent Transcriptional Plasticity.

    Science.gov (United States)

    Jonckheere, Wim; Dermauw, Wannes; Khalighi, Mousaalreza; Pavlidi, Nena; Reubens, Wim; Baggerman, Geert; Tirry, Luc; Menschaert, Gerben; Kant, Merijn R; Vanholme, Bartel; Van Leeuwen, Thomas

    2018-01-01

    The salivary protein repertoire released by the herbivorous pest Tetranychus urticae is assumed to hold keys to its success on diverse crops. We report on a spider mite-specific protein family that is expanded in T. urticae. The encoding genes have an expression pattern restricted to the anterior podocephalic glands, while peptide fragments were found in the T. urticae secretome, supporting the salivary nature of these proteins. As peptide fragments were identified in a host-dependent manner, we designated this family as the SHOT (secreted host-responsive protein of Tetranychidae) family. The proteins were divided in three groups based on sequence similarity. Unlike TuSHOT3 genes, TuSHOT1 and TuSHOT2 genes were highly expressed when feeding on a subset of family Fabaceae, while expression was depleted on other hosts. TuSHOT1 and TuSHOT2 expression was induced within 24 h after certain host transfers, pointing toward transcriptional plasticity rather than selection as the cause. Transfer from an 'inducer' to a 'noninducer' plant was associated with slow yet strong downregulation of TuSHOT1 and TuSHOT2, occurring over generations rather than hours. This asymmetric on and off regulation points toward host-specific effects of SHOT proteins, which is further supported by the diversity of SHOT genes identified in Tetranychidae with a distinct host repertoire.

  5. The SWEET gene family in Hevea brasiliensis - its evolution and expression compared with four other plant species.

    Science.gov (United States)

    Sui, Jin-Lei; Xiao, Xiao-Hu; Qi, Ji-Yan; Fang, Yong-Jun; Tang, Chao-Rong

    2017-12-01

    SWEET proteins play an indispensable role as a sugar efflux transporter in plant development and stress responses. The SWEET genes have previously been characterized in several plants. Here, we present a comprehensive analysis of this gene family in the rubber tree, Hevea brasiliensis . There are 36 members of the SWEET gene family in this species, making it one of the largest families in plant genomes sequenced so far. Structure and phylogeny analyses of these genes in Hevea and in other species demonstrated broad evolutionary conservation. RNA-seq analyses revealed that SWEET2, 16, and 17 might represent the main evolutionary direction of SWEET genes in plants. Our results in Hevea suggested the involvement of HbSWEET1a , 2e , 2f , and 3b in phloem loading, HbSWEET10a and 16b in laticifer sugar transport , and HbSWEET9a in nectary-specific sugar transport. Parallel studies of RNA-seq analyses extended to three other plant species ( Manihot esculenta , Populus trichocarpa , and Arabidopsis thaliana ) produced findings which implicated MeSWEET10a, 3a, and 15b in M. esculenta storage root development, and the involvement of PtSWEET16b and PtSWEET16d in P. trichocarpa xylem development. RT-qPCR results further revealed that HbSWEET10a, 16b, and 1a play important roles in phloem sugar transport. The results from this study provide a foundation not only for further investigation into the functionality of the SWEET gene family in Hevea, especially in its sugar transport for latex production, but also for related studies of this gene family in the plant kingdom.

  6. Real-time polymerase chain reaction assay for endogenous reference gene for specific detection and quantification of common wheat-derived DNA (Triticum aestivum L.).

    Science.gov (United States)

    Vautrin, Sonia; Zhang, David

    2007-01-01

    A species-specific endogenous reference gene system was developed for polymerase chain reaction (PCR)-based analysis in common wheat (Triticum aestivum L.) by targeting the ALMT1 gene, an aluminium-activated malate transporter. The primers and probe were elaborated for real-time PCR-based qualitative and quantitative assay. The size of amplified product is 95 base pairs. The specificity was assessed on 17 monocot and dicot plant species. The established real-time PCR assay amplified only T. aestivum-derived DNA; no amplification occurred on other phylogenetically related species, including durum wheat (T. durum). The robustness of the system was tested on the DNA of 15 common wheat cultivars using 20 000 genomic copies per PCR the mean cycle threshold (Ct) values of 24.02 +/- 0.251 were obtained. The absolute limits of detection and quantification of the real-time PCR assay were estimated to 2 and 20 haploid genome copies of common wheat, respectively. The linearity was experimentally validated on 2-fold serial dilutions of DNA from 650 to 20 000 haploid genome copies. All these results show that the real-time PCR assay developed on the ALMT1 gene is suitable to be used as an endogenous reference gene for PCR-based specific detection and quantification of T. aestivum-derived DNA in various applications, in particular for the detection and quantification of genetically modified materials in common wheat.

  7. Occurrence of theobromine synthase genes in purine alkaloid-free species of Camellia plants.

    Science.gov (United States)

    Ishida, Mariko; Kitao, Naoko; Mizuno, Kouichi; Tanikawa, Natsu; Kato, Misako

    2009-02-01

    Caffeine (1,3,7-trimethylxanthine) and theobromine (3,7-dimethylxanthine) are purine alkaloids that are present in high concentrations in plants of some species of Camellia. However, most members of the genus Camellia contain no purine alkaloids. Tracer experiments using [8-(14)C]adenine and [8-(14)C]theobromine showed that the purine alkaloid pathway is not fully functional in leaves of purine alkaloid-free species. In five species of purine alkaloid-free Camellia plants, sufficient evidence was obtained to show the occurrence of genes that are homologous to caffeine synthase. Recombinant enzymes derived from purine alkaloid-free species showed only theobromine synthase activity. Unlike the caffeine synthase gene, these genes were expressed more strongly in mature tissue than in young tissue.

  8. Identification and comparative analysis of sixteen fungal peptidyl-prolyl cis/trans isomerase repertoires

    Directory of Open Access Journals (Sweden)

    Pemberton Trevor J

    2006-09-01

    Full Text Available Abstract Background The peptidyl-prolyl cis/trans isomerase (PPIase class of proteins is present in all known eukaryotes, prokaryotes, and archaea, and it is comprised of three member families that share the ability to catalyze the cis/trans isomerisation of a prolyl bond. Some fungi have been used as model systems to investigate the role of PPIases within the cell, however how representative these repertoires are of other fungi or humans has not been fully investigated. Results PPIase numbers within these fungal repertoires appears associated with genome size and orthology between repertoires was found to be low. Phylogenetic analysis showed the single-domain FKBPs to evolve prior to the multi-domain FKBPs, whereas the multi-domain cyclophilins appear to evolve throughout cyclophilin evolution. A comparison of their known functions has identified, besides a common role within protein folding, multiple roles for the cyclophilins within pre-mRNA splicing and cellular signalling, and within transcription and cell cycle regulation for the parvulins. However, no such commonality was found with the FKBPs. Twelve of the 17 human cyclophilins and both human parvulins, but only one of the 13 human FKBPs, identified orthologues within these fungi. hPar14 orthologues were restricted to the Pezizomycotina fungi, and R. oryzae is unique in the known fungi in possessing an hCyp33 orthologue and a TPR-containing FKBP. The repertoires of Cryptococcus neoformans, Aspergillus fumigatus, and Aspergillus nidulans were found to exhibit the highest orthology to the human repertoire, and Saccharomyces cerevisiae one of the lowest. Conclusion Given this data, we would hypothesize that: (i the evolution of the fungal PPIases is driven, at least in part, by the size of the proteome, (ii evolutionary pressures differ both between the different PPIase families and the different fungi, and (iii whilst the cyclophilins and parvulins have evolved to perform conserved

  9. Persisting fetal clonotypes influence the structure and overlap of adult human T cell receptor repertoires.

    Directory of Open Access Journals (Sweden)

    Mikhail V Pogorelyy

    2017-07-01

    Full Text Available The diversity of T-cell receptors recognizing foreign pathogens is generated through a highly stochastic recombination process, making the independent production of the same sequence rare. Yet unrelated individuals do share receptors, which together constitute a "public" repertoire of abundant clonotypes. The TCR repertoire is initially formed prenatally, when the enzyme inserting random nucleotides is downregulated, producing a limited diversity subset. By statistically analyzing deep sequencing T-cell repertoire data from twins, unrelated individuals of various ages, and cord blood, we show that T-cell clones generated before birth persist and maintain high abundances in adult organisms for decades, slowly decaying with age. Our results suggest that large, low-diversity public clones are created during pre-natal life, and survive over long periods, providing the basis of the public repertoire.

  10. Evidence for gene flow between two sympatric mealybug species (Insecta; Coccoidea; Pseudococcidae.

    Directory of Open Access Journals (Sweden)

    Hofit Kol-Maimon

    Full Text Available Occurrence of inter-species hybrids in natural populations might be evidence of gene flow between species. In the present study we found evidence of gene flow between two sympatric, genetically related scale insect species--the citrus mealybug Planococcus citri (Risso and the vine mealybug Planococcus ficus (Signoret. These species can be distinguished by morphological, behavioral, and molecular traits. We employed the sex pheromones of the two respective species to study their different patterns of male attraction. We also used nuclear ITS2 (internal transcribed spacer 2 and mitochondrial COI (Cytochrome c oxidase sub unit 1 DNA sequences to characterize populations of the two species, in order to demonstrate the outcome of a possible gene flow between feral populations of the two species. Our results showed attraction to P. ficus pheromones of all tested populations of P. citri males but not vice versa. Furthermore, ITS2 sequences revealed the presence of 'hybrid females' among P. citri populations but not among those of P. ficus. 'hybrid females' from P. citri populations identified as P. citri females according to COI sequences. We offer two hypotheses for these results. 1 The occurrence of phenotypic and genotypic traits of P. ficus in P. citri populations may be attributed to both ancient and contemporary gene flow between their populations; and 2 we cannot rule out that an ancient sympatric speciation by which P. ficus emerged from P. citri might have led to the present situation of shared traits between these species. In light of these findings we also discuss the origin of the studied species and the importance of the pherotype phenomenon as a tool with which to study genetic relationships between congener scale insects.

  11. Identification, characterisation and expression analysis of natural killer receptor genes in Chlamydia pecorum infected koalas (Phascolarctos cinereus).

    Science.gov (United States)

    Morris, Katrina M; Mathew, Marina; Waugh, Courtney; Ujvari, Beata; Timms, Peter; Polkinghorne, Adam; Belov, Katherine

    2015-10-15

    Koalas (Phascolarctos cinereus), an iconic Australian marsupial, are being heavily impacted by the spread of Chlamydia pecorum, an obligate intracellular bacterial pathogen. Koalas vary in their response to this pathogen, with some showing no symptoms, while others suffer severe symptoms leading to infertility, blindness or death. Little is known about the pathology of this disease and the immune response against it in this host. Studies have demonstrated that natural killer (NK) cells, key components of the innate immune system, are involved in the immune response to chlamydial infections in humans. These cells can directly lyse cells infected by intracellular pathogens and their ability to recognise these infected cells is mediated through NK receptors on their surface. These are encoded in two regions of the genome, the leukocyte receptor complex (LRC) and the natural killer complex (NKC). These two families evolve rapidly and different repertoires of genes, which have evolved by gene duplication, are seen in different species. In this study we aimed to characterise genes belonging to the NK receptor clusters in the koala by searching available koala transcriptomes using a combination of search methods. We developed a qPCR assay to quantify relative expression of four genes, two encoded within the NK receptor cluster (CLEC1B, CLEC4E) and two known to play a role in NK response to Chalmydia in humans (NCR3, PRF1). We found that the NK receptor repertoire of the koala closely resembles that of the Tasmanian devil, with minimal genes in the NKC, but with lineage specific expansions in the LRC. Additional genes important for NK cell activity, NCR3 and PRF1, were also identified and characterised. In a preliminary study to investigate whether these genes are involved in the koala immune response to infection by its chlamydial pathogen, C. pecorum, we investigated the expression of four genes in koalas with active chlamydia infection, those with past infection and

  12. New strategies for designing inexpensive but selective bioadsorbants for environmental pollutants: Selection of specific ligands and their cell surface expression. Technical progress report, September 15, 1996 -September 14, 1997

    International Nuclear Information System (INIS)

    Iverson, B.

    1997-01-01

    'Progress for the last twelve months has revolved around setting up an antibody engineering and surface display system for use with a metal-complex binding antibody. (1) The author has isolated genes for the V regions of the heavy and light chains for the Ru(bpy)3 specific monoclonal AC1106 (Shreder, K S., Hariman, A., and Iverson, B.L., J. Am. Chem. Soc. 1996, 118, 3192-3201). This antibody binds Ru(bpy), derivatives with better than nanomolar affinity, and will serve as the generic metal-complex binding pocket. Cloning antibody genes from hybridomas is complicated by the fact that primers must be found that amplify the particular heavy and light chain genes in the hybridoma of interest. Antibody gene amplification primers are generally designed to amplify antibody repertoires from lymphocyte mRNA isolated from animals. While cloning repertoires from animals is routinely successful due to the diverse population of target m RNA, hybridomas have a single target sequence. Therefore, multiple primers and conditions must be tried before the correct primer combination is identified.'

  13. Genome-scale analysis of positional clustering of mouse testis-specific genes

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    Lee Bernett TK

    2005-01-01

    Full Text Available Abstract Background Genes are not randomly distributed on a chromosome as they were thought even after removal of tandem repeats. The positional clustering of co-expressed genes is known in prokaryotes and recently reported in several eukaryotic organisms such as Caenorhabditis elegans, Drosophila melanogaster, and Homo sapiens. In order to further investigate the mode of tissue-specific gene clustering in higher eukaryotes, we have performed a genome-scale analysis of positional clustering of the mouse testis-specific genes. Results Our computational analysis shows that a large proportion of testis-specific genes are clustered in groups of 2 to 5 genes in the mouse genome. The number of clusters is much higher than expected by chance even after removal of tandem repeats. Conclusion Our result suggests that testis-specific genes tend to cluster on the mouse chromosomes. This provides another piece of evidence for the hypothesis that clusters of tissue-specific genes do exist.

  14. Immune Repertoire Characteristics and Dynamics in Cancer

    DEFF Research Database (Denmark)

    Liu, Xiao

    The diversity of T and B cells in terms of their receptors is huge in the invertebrate’s immune system, to provide broad protection against the vast diversity of pathogens. Immune repertoire is defined as the sum of total subtypes that makes the organism’s immune system, either T cell receptor or...

  15. A dual-specificity isoform of the protein kinase inhibitor PKI produced by alternate gene splicing.

    Science.gov (United States)

    Kumar, Priyadarsini; Walsh, Donal A

    2002-03-15

    We have previously shown that the protein kinase inhibitor beta (PKIbeta) form of the cAMP-dependent protein kinase inhibitor exists in multiple isoforms, some of which are specific inhibitors of the cAMP-dependent protein kinase, whereas others also inhibit the cGMP-dependent enzyme [Kumar, Van Patten and Walsh (1997), J. Biol. Chem. 272, 20011-20020]. We have now demonstrated that the switch from a cAMP-dependent protein kinase (PKA)-specific inhibitor to one with dual specificity arises as a consequence of alternate gene splicing. We have confirmed using bacterially produced pure protein that a single inhibitor species has dual specificity for both PKA and cGMP-dependent protein kinase (PKG), inhibiting each with very high and closely similar inhibitory potencies. The gene splicing converted a protein with 70 amino acids into one of 109 amino acids, and did not change the inhibitory potency to PKA, but changed it from a protein that had no detectable PKG inhibitory activity to one that now inhibited PKG in the nanomolar range.

  16. Wheat-specific gene, ribosomal protein l21, used as the endogenous reference gene for qualitative and real-time quantitative polymerase chain reaction detection of transgenes.

    Science.gov (United States)

    Liu, Yi-Ke; Li, He-Ping; Huang, Tao; Cheng, Wei; Gao, Chun-Sheng; Zuo, Dong-Yun; Zhao, Zheng-Xi; Liao, Yu-Cai

    2014-10-29

    Wheat-specific ribosomal protein L21 (RPL21) is an endogenous reference gene suitable for genetically modified (GM) wheat identification. This taxon-specific RPL21 sequence displayed high homogeneity in different wheat varieties. Southern blots revealed 1 or 3 copies, and sequence analyses showed one amplicon in common wheat. Combined analyses with sequences from common wheat (AABBDD) and three diploid ancestral species, Triticum urartu (AA), Aegilops speltoides (BB), and Aegilops tauschii (DD), demonstrated the presence of this amplicon in the AA genome. Using conventional qualitative polymerase chain reaction (PCR), the limit of detection was 2 copies of wheat haploid genome per reaction. In the quantitative real-time PCR assay, limits of detection and quantification were about 2 and 8 haploid genome copies, respectively, the latter of which is 2.5-4-fold lower than other reported wheat endogenous reference genes. Construct-specific PCR assays were developed using RPL21 as an endogenous reference gene, and as little as 0.5% of GM wheat contents containing Arabidopsis NPR1 were properly quantified.

  17. Use of Phage Antibodies to Distinguish Closely Related Species of Protozoan Parasites

    Directory of Open Access Journals (Sweden)

    Timothy Paget

    2000-01-01

    Full Text Available Acanthamoeba are typically identified in the laboratory using culture and microscopic observation. In this paper we describe the isolation and specificity of antibody fragments that can be used for the identification of Acanthamoeba. A phage library expressing a large repertoire (approx. 5×109 of antibody fragments was used to generate two libraries one enriched for bacteriophage that exhibit genus specific binding and the other containing bacteriophage that bind specifically to pathogenic Acanthamoeba. Individual clones were isolated on the basis of binding by ELISA, and then flowcytometry and immunofluorescence were used for further characterisation. Four monoclonal antibodies were isolated, specific for Acanthamoeba at the generic level with clone HPPG6 exhibiting the highest level of binding. Furthermore clone HPPG55 was specific for pathogenic species of Acanthamoeba.

  18. Characterisation of the NUCKS gene on human chromosome 1q32.1 and the presence of a homologous gene in different species

    International Nuclear Information System (INIS)

    Grundt, Kirsten; Haga, Ingvild Vagslid; Aleporou-Marinou, Vasiliki; Drosos, Yiannis; Wanvik, Birgit; Ostvold, Anne Carine

    2004-01-01

    The NUCKS gene is located on human chromosome 1q32.1 and consists of seven exons and six introns. The gene lacks a TATA box but contains two Inr elements, two GC boxes, and one consensus-binding site for E2F-1. NUCKS is expressed in all human adult and foetal tissues investigated, and has all the features of being a housekeeping gene. Both data searches and Western immunoblotting experiments show that a homologous protein is present in fish, amphibians, and birds but not in insects and yeast, suggesting that NUCKS is a vertebrate specific gene. In all the species investigated, the protein contains several consensus phosphorylation sites for cyclin-dependent kinases and CK-2, and we have shown that the fish protein (like mammalian NUCKS) indeed is a substrate for CDK1 and CK-2 in vitro. The NUCKS protein is also conserved with respect to a DNA-binding domain previously characterised in mammals, and two putative bipartite nuclear localisation signals

  19. Identification of Candidate B-Lymphoma Genes by Cross-Species Gene Expression Profiling

    Science.gov (United States)

    Tompkins, Van S.; Han, Seong-Su; Olivier, Alicia; Syrbu, Sergei; Bair, Thomas; Button, Anna; Jacobus, Laura; Wang, Zebin; Lifton, Samuel; Raychaudhuri, Pradip; Morse, Herbert C.; Weiner, George; Link, Brian; Smith, Brian J.; Janz, Siegfried

    2013-01-01

    Comparative genome-wide expression profiling of malignant tumor counterparts across the human-mouse species barrier has a successful track record as a gene discovery tool in liver, breast, lung, prostate and other cancers, but has been largely neglected in studies on neoplasms of mature B-lymphocytes such as diffuse large B cell lymphoma (DLBCL) and Burkitt lymphoma (BL). We used global gene expression profiles of DLBCL-like tumors that arose spontaneously in Myc-transgenic C57BL/6 mice as a phylogenetically conserved filter for analyzing the human DLBCL transcriptome. The human and mouse lymphomas were found to have 60 concordantly deregulated genes in common, including 8 genes that Cox hazard regression analysis associated with overall survival in a published landmark dataset of DLBCL. Genetic network analysis of the 60 genes followed by biological validation studies indicate FOXM1 as a candidate DLBCL and BL gene, supporting a number of studies contending that FOXM1 is a therapeutic target in mature B cell tumors. Our findings demonstrate the value of the “mouse filter” for genomic studies of human B-lineage neoplasms for which a vast knowledge base already exists. PMID:24130802

  20. Utility of combining morphological characters, nuclear and mitochondrial genes: An attempt to resolve the conflicts of species identification for ciliated protists.

    Science.gov (United States)

    Zhao, Yan; Yi, Zhenzhen; Gentekaki, Eleni; Zhan, Aibin; Al-Farraj, Saleh A; Song, Weibo

    2016-01-01

    Ciliates comprise a highly diverse protozoan lineage inhabiting all biotopes and playing crucial roles in regulating microbial food webs. Nevertheless, subtle morphological differences and tiny sizes hinder proper species identification for many ciliates. Here, we use the species-rich taxon Frontonia and employ both nuclear and mitochondrial loci. We attempt to assess the level of genetic diversity and evaluate the potential of each marker in delineating species of Frontonia. Morphological features and ecological characteristics are also integrated into genetic results, in an attempt to resolve conflicts of species identification based on morphological and molecular methods. Our studies reveal: (1) the mitochondrial cox1 gene, nuclear ITS1 and ITS2 as well as the hypervariable D2 region of LSU rDNA are promising candidates for species delineation; (2) the cox1 gene provides the best resolution for analyses below the species level; (3) the V2 and V4 hypervariable regions of SSU rDNA, and D1 of LSU rDNA as well as the 5.8S rDNA gene do not show distinct barcoding gap due to overlap between intra- and inter-specific genetic divergences; (4) morphological character-based analysis shows promise for delimitation of Frontonia species; and (5) all gene markers and character-based analyses demonstrate that the genus Frontonia consists of three groups and monophyly of the genus Frontonia is questionable. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Lunar Gene Bank for Endangered Species

    Science.gov (United States)

    Swain, Ramakrushna

    2016-07-01

    Introduction: Before the dawn of the 22nd century, we face the huge risk of losing our genetic heritage accumulated during aeons of evolution. The losses include hundreds of vertebrates, human gene pools, hundreds of thousands of plants and over a million insect species. As we have observed, adequate conservation of habitat is unfeasible and active breeding programs cover only a handful of the many thousand species threatened. We propose cryopreservation of germplasms by constructing a cDNA library based gene bank for endangered species in the permanently shadowed polar lunar craters that would provide immunity from both natural disadvantages and humanitarian intrusions. Rationale: Under such alarming circumstances, we turned to cryopreservation as an option but over thousands of years economic depression, sabotage, conflicts, warfare or even a brief disruption to the precise cryopreservation can hamper the storage of genetic samples.When we are considering conservation it is always preferable to go for a more secure and permanent solution. It was found out that the climatic and strategic location of the lunar polar craters are adequately hospitable, remote and free of maintenance and human observation as they provide naturally cryogenic temperature, reduced gravity and vacuum environment, non-reactive surface, safety from celestial intrusion and permanent shadow which doesn't allow the temperature to fluctuate thus providing most suitable storage facilities for the germplasms. PSRs provide steady temperature of 40- 60K and immunity to earthquakes due to low seismic activity. At these sites, burial in one meter or more of the regolith will provide protection against the solar wind, solar and galactic cosmic rays and micrometeorite impact. It provides the minimum necessary barrier from human intervention and at the same time enables easy retrieval for future usage. Genetic samples of endangered species can enable restoration even after its extinction. Preserved

  2. Identification of novel target genes for safer and more specific control of root-knot nematodes from a pan-genome mining.

    Directory of Open Access Journals (Sweden)

    Etienne G J Danchin

    2013-10-01

    Full Text Available Root-knot nematodes are globally the most aggressive and damaging plant-parasitic nematodes. Chemical nematicides have so far constituted the most efficient control measures against these agricultural pests. Because of their toxicity for the environment and danger for human health, these nematicides have now been banned from use. Consequently, new and more specific control means, safe for the environment and human health, are urgently needed to avoid worldwide proliferation of these devastating plant-parasites. Mining the genomes of root-knot nematodes through an evolutionary and comparative genomics approach, we identified and analyzed 15,952 nematode genes conserved in genomes of plant-damaging species but absent from non target genomes of chordates, plants, annelids, insect pollinators and mollusks. Functional annotation of the corresponding proteins revealed a relative abundance of putative transcription factors in this parasite-specific set compared to whole proteomes of root-knot nematodes. This may point to important and specific regulators of genes involved in parasitism. Because these nematodes are known to secrete effector proteins in planta, essential for parasitism, we searched and identified 993 such effector-like proteins absent from non-target species. Aiming at identifying novel targets for the development of future control methods, we biologically tested the effect of inactivation of the corresponding genes through RNA interference. A total of 15 novel effector-like proteins and one putative transcription factor compatible with the design of siRNAs were present as non-redundant genes and had transcriptional support in the model root-knot nematode Meloidogyne incognita. Infestation assays with siRNA-treated M. incognita on tomato plants showed significant and reproducible reduction of the infestation for 12 of the 16 tested genes compared to control nematodes. These 12 novel genes, showing efficient reduction of parasitism when

  3. Species-specific chitin-binding module 18 expansion in the amphibian pathogen Batrachochytrium dendrobatidis.

    Science.gov (United States)

    Abramyan, John; Stajich, Jason E

    2012-01-01

    Batrachochytrium dendrobatidis is the causative agent of chytridiomycosis, which is considered one of the driving forces behind the worldwide decline in populations of amphibians. As a member of the phylum Chytridiomycota, B. dendrobatidis has diverged significantly to emerge as the only pathogen of adult vertebrates. Such shifts in lifestyle are generally accompanied by various degrees of genomic modifications, yet neither its mode of pathogenicity nor any factors associated with it have ever been identified. Presented here is the identification and characterization of a unique expansion of the carbohydrate-binding module family 18 (CBM18), specific to B. dendrobatidis. CBM (chitin-binding module) expansions have been likened to the evolution of pathogenicity in a variety of fungus species, making this expanded group a prime candidate for the identification of potential pathogenicity factors. Furthermore, the CBM18 expansions are confined to three categories of genes, each having been previously implicated in host-pathogen interactions. These correlations highlight this specific domain expansion as a potential key player in the mode of pathogenicity in this unique fungus. The expansion of CBM18 in B. dendrobatidis is exceptional in its size and diversity compared to other pathogenic species of fungi, making this genomic feature unique in an evolutionary context as well as in pathogenicity. Amphibian populations are declining worldwide at an unprecedented rate. Although various factors are thought to contribute to this phenomenon, chytridiomycosis has been identified as one of the leading causes. This deadly fungal disease is cause by Batrachochytrium dendrobatidis, a chytrid fungus species unique in its pathogenicity and, furthermore, its specificity to amphibians. Despite more than two decades of research, the biology of this fungus species and its deadly interaction with amphibians had been notoriously difficult to unravel. Due to the alarming rate of worldwide

  4. Sex identification of four penguin species using locus-specific PCR.

    Science.gov (United States)

    Zhang, Peijun; Han, Jiabo; Liu, Quansheng; Zhang, Junxin; Zhang, Xianfeng

    2013-01-01

    Traditional methods for sex identification are not applicable to sexually monomorphic species, leading to difficulties in the management of their breeding programs. To identify sex in sexually monomorphic birds, molecular methods have been established. Two established primer pairs (2550F/2718R and p8/p2) amplify the CHD1 gene region from both the Z and W chromosomes. Here, we evaluated the use of these primers for sex identification in four sexually monomorphic penguin species: king penguins (Aptenodytes patagonicus), rockhopper penguins (Eudyptes chrysocome), gentoo penguins (Pygoscelis papua), and Magellanic penguins (Spheniscus magellanicus). For all species except rockhopper penguins, primer pair 2550F/2718R resulted in two distinct CHD1Z and CHD1W PCR bands, allowing for sex identification. For rockhopper penguins, only primer pair p8/p2 yielded different CHD1Z and CHD1W bands, which were faint and similar in size making them difficult to distinguish. As a result, we designed a new primer pair (PL/PR) that efficiently determined the gender of individuals from all four penguin species. Sequencing of the PCR products confirmed that they were from the CHD1 gene region. Primer pair PL/PR can be evaluated for use in sexing other penguin species, which will be crucial for the management of new penguin breeding programs. © 2012 Wiley Periodicals, Inc.

  5. Elucidation of primary metabolic pathways in Aspergillus species: Orphaned research in characterizing orphan genes

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam

    2014-01-01

    metabolites and extracellular enzymes. In this review, all annotated genes from four Aspergillus species have been examined. In this process, it becomes evident that 80-96% of the genes (depending on the species) are still without verified function. A significant proportion of the genes with verified......, applications of this from the Aspergillus genes will be examined, and it is proposed that, where feasible, this should be a standard part of functional annotation of fungal genomes....

  6. Genome-wide analysis of the expansin gene superfamily reveals grapevine-specific structural and functional characteristics.

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    Silvia Dal Santo

    Full Text Available BACKGROUND: Expansins are proteins that loosen plant cell walls in a pH-dependent manner, probably by increasing the relative movement among polymers thus causing irreversible expansion. The expansin superfamily (EXP comprises four distinct families: expansin A (EXPA, expansin B (EXPB, expansin-like A (EXLA and expansin-like B (EXLB. There is experimental evidence that EXPA and EXPB proteins are required for cell expansion and developmental processes involving cell wall modification, whereas the exact functions of EXLA and EXLB remain unclear. The complete grapevine (Vitis vinifera genome sequence has allowed the characterization of many gene families, but an exhaustive genome-wide analysis of expansin gene expression has not been attempted thus far. METHODOLOGY/PRINCIPAL FINDINGS: We identified 29 EXP superfamily genes in the grapevine genome, representing all four EXP families. Members of the same EXP family shared the same exon-intron structure, and phylogenetic analysis confirmed a closer relationship between EXP genes from woody species, i.e. grapevine and poplar (Populus trichocarpa, compared to those from Arabidopsis thaliana and rice (Oryza sativa. We also identified grapevine-specific duplication events involving the EXLB family. Global gene expression analysis confirmed a strong correlation among EXP genes expressed in mature and green/vegetative samples, respectively, as reported for other gene families in the recently-published grapevine gene expression atlas. We also observed the specific co-expression of EXLB genes in woody organs, and the involvement of certain grapevine EXP genes in berry development and post-harvest withering. CONCLUSION: Our comprehensive analysis of the grapevine EXP superfamily confirmed and extended current knowledge about the structural and functional characteristics of this gene family, and also identified properties that are currently unique to grapevine expansin genes. Our data provide a model for the

  7. Expression and genomic organization of zonadhesin-like genes in three species of fish give insight into the evolutionary history of a mosaic protein

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    Davidson William S

    2005-11-01

    Full Text Available Abstract Background The mosaic sperm protein zonadhesin (ZAN has been characterized in mammals and is implicated in species-specific egg-sperm binding interactions. The genomic structure and testes-specific expression of zonadhesin is known for many mammalian species. All zonadhesin genes characterized to date consist of meprin A5 antigen receptor tyrosine phosphatase mu (MAM domains, mucin tandem repeats, and von Willebrand (VWD adhesion domains. Here we investigate the genomic structure and expression of zonadhesin-like genes in three species of fish. Results The cDNA and corresponding genomic locus of a zonadhesin-like gene (zlg in Atlantic salmon (Salmo salar were sequenced. Zlg is similar in adhesion domain content to mammalian zonadhesin; however, the domain order is altered. Analysis of puffer fish (Takifugu rubripes and zebrafish (Danio rerio sequence data identified zonadhesin (zan genes that share the same domain order, content, and a conserved syntenic relationship with mammalian zonadhesin. A zonadhesin-like gene in D. rerio was also identified. Unlike mammalian zonadhesin, D. rerio zan and S. salar zlg were expressed in the gut and not in the testes. Conclusion We characterized likely orthologs of zonadhesin in both T. rubripes and D. rerio and uncovered zonadhesin-like genes in S. salar and D. rerio. Each of these genes contains MAM, mucin, and VWD domains. While these domains are associated with several proteins that show prominent gut expression, their combination is unique to zonadhesin and zonadhesin-like genes in vertebrates. The expression patterns of fish zonadhesin and zonadhesin-like genes suggest that the reproductive role of zonadhesin evolved later in the mammalian lineage.

  8. Mining tissue specificity, gene connectivity and disease association to reveal a set of genes that modify the action of disease causing genes

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    Reverter Antonio

    2008-09-01

    Full Text Available Abstract Background The tissue specificity of gene expression has been linked to a number of significant outcomes including level of expression, and differential rates of polymorphism, evolution and disease association. Recent studies have also shown the importance of exploring differential gene connectivity and sequence conservation in the identification of disease-associated genes. However, no study relates gene interactions with tissue specificity and disease association. Methods We adopted an a priori approach making as few assumptions as possible to analyse the interplay among gene-gene interactions with tissue specificity and its subsequent likelihood of association with disease. We mined three large datasets comprising expression data drawn from massively parallel signature sequencing across 32 tissues, describing a set of 55,606 true positive interactions for 7,197 genes, and microarray expression results generated during the profiling of systemic inflammation, from which 126,543 interactions among 7,090 genes were reported. Results Amongst the myriad of complex relationships identified between expression, disease, connectivity and tissue specificity, some interesting patterns emerged. These include elevated rates of expression and network connectivity in housekeeping and disease-associated tissue-specific genes. We found that disease-associated genes are more likely to show tissue specific expression and most frequently interact with other disease genes. Using the thresholds defined in these observations, we develop a guilt-by-association algorithm and discover a group of 112 non-disease annotated genes that predominantly interact with disease-associated genes, impacting on disease outcomes. Conclusion We conclude that parameters such as tissue specificity and network connectivity can be used in combination to identify a group of genes, not previously confirmed as disease causing, that are involved in interactions with disease causing

  9. The evolution of multiple isotypic IgM heavy chain genes in the shark.

    Science.gov (United States)

    Lee, Victor; Huang, Jing Li; Lui, Ming Fai; Malecek, Karolina; Ohta, Yuko; Mooers, Arne; Hsu, Ellen

    2008-06-01

    The IgM H chain gene organization of cartilaginous fishes consists of 15-200 miniloci, each with a few gene segments (V(H)-D1-D2-J(H)) and one C gene. This is a gene arrangement ancestral to the complex IgH locus that exists in all other vertebrate classes. To understand the molecular evolution of this system, we studied the nurse shark, which has relatively fewer loci, and characterized the IgH isotypes for organization, functionality, and the somatic diversification mechanisms that act upon them. Gene numbers differ slightly between individuals ( approximately 15), but five active IgM subclasses are always present. Each gene undergoes rearrangement that is strictly confined within the minilocus; in B cells there is no interaction between adjacent loci located > or =120 kb apart. Without combinatorial events, the shark IgM H chain repertoire is based on junctional diversity and, subsequently, somatic hypermutation. We suggest that the significant contribution by junctional diversification reflects the selected novelty introduced by RAG in the early vertebrate ancestor, whereas combinatorial diversity coevolved with the complex translocon organization. Moreover, unlike other cartilaginous fishes, there are no germline-joined VDJ at any nurse shark mu locus, and we suggest that such genes, when functional, are species-specific and may have specialized roles. With an entire complement of IgM genes available for the first time, phylogenetic analyses were performed to examine how the multiple Ig loci evolved. We found that all domains changed at comparable rates, but V(H) appears to be under strong positive selection for increased amino acid sequence diversity, and surprisingly, so does Cmicro2.

  10. Genome-wide analysis of the sox family in the calcareous sponge Sycon ciliatum: multiple genes with unique expression patterns

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    Fortunato Sofia

    2012-07-01

    Full Text Available Abstract Background Sox genes are HMG-domain containing transcription factors with important roles in developmental processes in animals; many of them appear to have conserved functions among eumetazoans. Demosponges have fewer Sox genes than eumetazoans, but their roles remain unclear. The aim of this study is to gain insight into the early evolutionary history of the Sox gene family by identification and expression analysis of Sox genes in the calcareous sponge Sycon ciliatum. Methods Calcaronean Sox related sequences were retrieved by searching recently generated genomic and transcriptome sequence resources and analyzed using variety of phylogenetic methods and identification of conserved motifs. Expression was studied by whole mount in situ hybridization. Results We have identified seven Sox genes and four Sox-related genes in the complete genome of Sycon ciliatum. Phylogenetic and conserved motif analyses showed that five of Sycon Sox genes represent groups B, C, E, and F present in cnidarians and bilaterians. Two additional genes are classified as Sox genes but cannot be assigned to specific subfamilies, and four genes are more similar to Sox genes than to other HMG-containing genes. Thus, the repertoire of Sox genes is larger in this representative of calcareous sponges than in the demosponge Amphimedon queenslandica. It remains unclear whether this is due to the expansion of the gene family in Sycon or a secondary reduction in the Amphimedon genome. In situ hybridization of Sycon Sox genes revealed a variety of expression patterns during embryogenesis and in specific cell types of adult sponges. Conclusions In this study, we describe a large family of Sox genes in Sycon ciliatum with dynamic expression patterns, indicating that Sox genes are regulators in development and cell type determination in sponges, as observed in higher animals. The revealed differences between demosponge and calcisponge Sox genes repertoire highlight the need to

  11. Characterization of Arabidopsis Transcriptional Responses to Different Aphid Species Reveals Genes that Contribute to Host Susceptibility and Non-host Resistance

    Science.gov (United States)

    Jaouannet, Maëlle; Morris, Jenny A.; Hedley, Peter E.; Bos, Jorunn I. B.

    2015-01-01

    Aphids are economically important pests that display exceptional variation in host range. The determinants of diverse aphid host ranges are not well understood, but it is likely that molecular interactions are involved. With significant progress being made towards understanding host responses upon aphid attack, the mechanisms underlying non-host resistance remain to be elucidated. Here, we investigated and compared Arabidopsis thaliana host and non-host responses to aphids at the transcriptional level using three different aphid species, Myzus persicae, Myzus cerasi and Rhopalosiphum pisum. Gene expression analyses revealed a high level of overlap in the overall gene expression changes during the host and non-host interactions with regards to the sets of genes differentially expressed and the direction of expression changes. Despite this overlap in transcriptional responses across interactions, there was a stronger repression of genes involved in metabolism and oxidative responses specifically during the host interaction with M. persicae. In addition, we identified a set of genes with opposite gene expression patterns during the host versus non-host interactions. Aphid performance assays on Arabidopsis mutants that were selected based on our transcriptome analyses identified novel genes contributing to host susceptibility, host defences during interactions with M. persicae as well to non-host resistance against R. padi. Understanding how plants respond to aphid species that differ in their ability to infest plant species, and identifying the genes and signaling pathways involved, is essential for the development of novel and durable aphid control in crop plants. PMID:25993686

  12. NSF Workshop Report: Discovering General Principles of Nervous System Organization by Comparing Brain Maps across Species

    Science.gov (United States)

    Striedter, Georg F.; Belgard, T. Grant; Chen, Chun-Chun; Davis, Fred P.; Finlay, Barbara L.; Güntürkün, Onur; Hale, Melina E.; Harris, Julie A.; Hecht, Erin E.; Hof, Patrick R.; Hofmann, Hans A.; Holland, Linda Z.; Iwaniuk, Andrew N.; Jarvis, Erich D.; Karten, Harvey J.; Katz, Paul S.; Kristan, William B.; Macagno, Eduardo R.; Mitra, Partha P.; Moroz, Leonid L.; Preuss, Todd M.; Ragsdale, Clifton W.; Sherwood, Chet C.; Stevens, Charles F.; Stüttgen, Maik C.; Tsumoto, Tadaharu; Wilczynski, Walter

    2014-01-01

    Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene-structure-function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps’ comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species’ to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well-annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be

  13. Rule-Governed Behavior: Teaching a Preliminary Repertoire of Rule-Following to Children with Autism

    Science.gov (United States)

    Tarbox, Jonathan; Zuckerman, Carrie K.; Bishop, Michele R.; Olive, Melissa L.; O'Hora, Denis P.

    2011-01-01

    Rule-governed behavior is generally considered an integral component of complex verbal repertoires but has rarely been the subject of empirical research. In particular, little or no previous research has attempted to establish rule-governed behavior in individuals who do not already display the repertoire. This study consists of two experiments…

  14. Evolution of divergent DNA recognition specificities in VDE homing endonucleases from two yeast species.

    Science.gov (United States)

    Posey, Karen L; Koufopanou, Vassiliki; Burt, Austin; Gimble, Frederick S

    2004-01-01

    Homing endonuclease genes (HEGs) are mobile DNA elements that are thought to confer no benefit to their host. They encode site-specific DNA endonucleases that perpetuate the element within a species population by homing and disseminate it between species by horizontal transfer. Several yeast species contain the VMA1 HEG that encodes the intein-associated VMA1-derived endonuclease (VDE). The evolutionary state of VDEs from 12 species was assessed by assaying their endonuclease activities. Only two enzymes are active, PI-ZbaI from Zygosaccharomyces bailii and PI-ScaI from Saccharomyces cariocanus. PI-ZbaI cleaves the Z.bailii recognition sequence significantly faster than the Saccharomyces cerevisiae site, which differs at six nucleotide positions. A mutational analysis indicates that PI-ZbaI cleaves the S.cerevisiae substrate poorly due to the absence of a contact that is analogous to one made in PI-SceI between Gln-55 and nucleotides +9/+10. PI-ZbaI cleaves the Z.bailii substrate primarily due to a single base-pair substitution (A/T+5 --> T/A+5). Structural modeling of the PI-ZbaI/DNA complex suggests that Arg-331, which is absent in PI-SceI, contacts T/A+5, and the reduced activity observed in a PI-ZbaI R331A mutant provides evidence for this interaction. These data illustrate that homing endonucleases evolve altered specificity as they adapt to recognize alternative target sites.

  15. Evolution of divergent DNA recognition specificities in VDE homing endonucleases from two yeast species

    Science.gov (United States)

    Posey, Karen L.; Koufopanou, Vassiliki; Burt, Austin; Gimble, Frederick S.

    2004-01-01

    Homing endonuclease genes (HEGs) are mobile DNA elements that are thought to confer no benefit to their host. They encode site-specific DNA endonucleases that perpetuate the element within a species population by homing and disseminate it between species by horizontal transfer. Several yeast species contain the VMA1 HEG that encodes the intein-associated VMA1-derived endonuclease (VDE). The evolutionary state of VDEs from 12 species was assessed by assaying their endonuclease activities. Only two enzymes are active, PI-ZbaI from Zygosaccharomyces bailii and PI-ScaI from Saccharomyces cariocanus. PI-ZbaI cleaves the Z.bailii recognition sequence significantly faster than the Saccharomyces cerevisiae site, which differs at six nucleotide positions. A mutational analysis indicates that PI-ZbaI cleaves the S.cerevisiae substrate poorly due to the absence of a contact that is analogous to one made in PI-SceI between Gln-55 and nucleotides +9/+10. PI-ZbaI cleaves the Z.bailii substrate primarily due to a single base-pair substitution (A/T+5 → T/A+5). Structural modeling of the PI-ZbaI/DNA complex suggests that Arg-331, which is absent in PI-SceI, contacts T/A+5, and the reduced activity observed in a PI-ZbaI R331A mutant provides evidence for this interaction. These data illustrate that homing endonucleases evolve altered specificity as they adapt to recognize alternative target sites. PMID:15280510

  16. Chromosomal mapping of H3 histone and 5S rRNA genes in eight species of Astyanax (Pisces, Characiformes) with different diploid numbers: syntenic conservation of repetitive genes.

    Science.gov (United States)

    Piscor, Diovani; Parise-Maltempi, Patricia Pasquali

    2016-03-01

    The genus Astyanax is widely distributed from the southern United States to northern Patagonia, Argentina. While cytogenetic studies have been performed for this genus, little is known about the histone gene families. The aim of this study was to examine the chromosomal relationships among the different species of Astyanax. The chromosomal locations of the 5S rRNA and H3 histone genes were determined in A. abramis, A. asuncionensis, A. altiparanae, A. bockmanni, A. eigenmanniorum, A. mexicanus (all 2n = 50), A. fasciatus (2n = 46), and A. schubarti (2n = 36). All eight species exhibited H3 histone clusters on two chromosome pairs. In six species (A. abramis, A. asuncionensis, A. altiparanae, A. bockmanni, A. eigenmanniorum, and A. fasciatus), syntenic clusters of H3 histone and 5S rDNA were observed on metacentric (m) or submetacentric (sm) chromosomes. In seven species, clusters of 5S rDNA sequences were located on one or two chromosome pairs. In A. mexicanus, 5S rDNA clusters were located on four chromosome pairs. This study demonstrates that H3 histone clusters are conserved on two chromosome pairs in the genus Astyanax, and specific chromosomal features may contribute to the genomic organization of the H3 histone and 5S rRNA genes.

  17. DLRS: gene tree evolution in light of a species tree.

    Science.gov (United States)

    Sjöstrand, Joel; Sennblad, Bengt; Arvestad, Lars; Lagergren, Jens

    2012-11-15

    PrIME-DLRS (or colloquially: 'Delirious') is a phylogenetic software tool to simultaneously infer and reconcile a gene tree given a species tree. It accounts for duplication and loss events, a relaxed molecular clock and is intended for the study of homologous gene families, for example in a comparative genomics setting involving multiple species. PrIME-DLRS uses a Bayesian MCMC framework, where the input is a known species tree with divergence times and a multiple sequence alignment, and the output is a posterior distribution over gene trees and model parameters. PrIME-DLRS is available for Java SE 6+ under the New BSD License, and JAR files and source code can be downloaded from http://code.google.com/p/jprime/. There is also a slightly older C++ version available as a binary package for Ubuntu, with download instructions at http://prime.sbc.su.se. The C++ source code is available upon request. joel.sjostrand@scilifelab.se or jens.lagergren@scilifelab.se. PrIME-DLRS is based on a sound probabilistic model (Åkerborg et al., 2009) and has been thoroughly validated on synthetic and biological datasets (Supplementary Material online).

  18. Acquisition and evolution of plant pathogenesis-associated gene clusters and candidate determinants of tissue-specificity in xanthomonas.

    Directory of Open Access Journals (Sweden)

    Hong Lu

    Full Text Available Xanthomonas is a large genus of plant-associated and plant-pathogenic bacteria. Collectively, members cause diseases on over 392 plant species. Individually, they exhibit marked host- and tissue-specificity. The determinants of this specificity are unknown.To assess potential contributions to host- and tissue-specificity, pathogenesis-associated gene clusters were compared across genomes of eight Xanthomonas strains representing vascular or non-vascular pathogens of rice, brassicas, pepper and tomato, and citrus. The gum cluster for extracellular polysaccharide is conserved except for gumN and sequences downstream. The xcs and xps clusters for type II secretion are conserved, except in the rice pathogens, in which xcs is missing. In the otherwise conserved hrp cluster, sequences flanking the core genes for type III secretion vary with respect to insertion sequence element and putative effector gene content. Variation at the rpf (regulation of pathogenicity factors cluster is more pronounced, though genes with established functional relevance are conserved. A cluster for synthesis of lipopolysaccharide varies highly, suggesting multiple horizontal gene transfers and reassortments, but this variation does not correlate with host- or tissue-specificity. Phylogenetic trees based on amino acid alignments of gum, xps, xcs, hrp, and rpf cluster products generally reflect strain phylogeny. However, amino acid residues at four positions correlate with tissue specificity, revealing hpaA and xpsD as candidate determinants. Examination of genome sequences of xanthomonads Xylella fastidiosa and Stenotrophomonas maltophilia revealed that the hrp, gum, and xcs clusters are recent acquisitions in the Xanthomonas lineage.Our results provide insight into the ancestral Xanthomonas genome and indicate that differentiation with respect to host- and tissue-specificity involved not major modifications or wholesale exchange of clusters, but subtle changes in a small

  19. Species differences in brain gene expression profiles associated with adult behavioral maturation in honey bees

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    Robinson Gene E

    2007-06-01

    Full Text Available Abstract Background Honey bees are known for several striking social behaviors, including a complex pattern of behavioral maturation that gives rise to an age-related colony division of labor and a symbolic dance language, by which successful foragers communicate the location of attractive food sources to their nestmates. Our understanding of honey bees is mostly based on studies of the Western honey bee, Apis mellifera, even though there are 9–10 other members of genus Apis, showing interesting variations in social behavior relative to A. mellifera. To facilitate future in-depth genomic and molecular level comparisons of behavior across the genus, we performed a microarray analysis of brain gene expression for A. mellifera and three key species found in Asia, A. cerana, A. florea and A. dorsata. Results For each species we compared brain gene expression patterns between foragers and adult one-day-old bees on an A. mellifera cDNA microarray and calculated within-species gene expression ratios to facilitate cross-species analysis. The number of cDNA spots showing hybridization fluorescence intensities above the experimental threshold was reduced by an average of 16% in the Asian species compared to A. mellifera, but an average of 71% of genes on the microarray were available for analysis. Brain gene expression profiles between foragers and one-day-olds showed differences that are consistent with a previous study on A. mellifera and were comparable across species. Although 1772 genes showed significant differences in expression between foragers and one-day-olds, only 218 genes showed differences in forager/one-day-old expression between species (p Conclusion We conclude that the A. mellifera cDNA microarray can be used effectively for cross-species comparisons within the genus. Our results indicate that there is a widespread conservation of the molecular processes in the honey bee brain underlying behavioral maturation. Species differences in

  20. Iterative Design toward Equity: Youth Repertoires of Practice in a High School Maker Space

    Science.gov (United States)

    Martin, Lee; Dixon, Colin; Betser, Sagit

    2018-01-01

    Despite their potential, maker activities do not always support equitable engagement. The authors report on a design research study where they worked to support equitable engagement of youth repertoires of practice in a high school makerspace. Their orientation toward equity is grounded in the construct of repertoires of practice, and they focus…

  1. Conservation and Sex-Specific Splicing of the transformer Gene in the Calliphorids Cochliomyia hominivorax, Cochliomyia macellaria and Lucilia sericata

    Science.gov (United States)

    Li, Fang; Vensko, Steven P.; Belikoff, Esther J.; Scott, Maxwell J.

    2013-01-01

    Transformer (TRA) promotes female development in several dipteran species including the Australian sheep blowfly Lucilia cuprina, the Mediterranean fruit fly, housefly and Drosophila melanogaster. tra transcripts are sex-specifically spliced such that only the female form encodes full length functional protein. The presence of six predicted TRA/TRA2 binding sites in the sex-specific female intron of the L. cuprina gene suggested that tra splicing is auto-regulated as in medfly and housefly. With the aim of identifying conserved motifs that may play a role in tra sex-specific splicing, here we have isolated and characterized the tra gene from three additional blowfly species, L. sericata, Cochliomyia hominivorax and C. macellaria. The blowfly adult male and female transcripts differ in the choice of splice donor site in the first intron, with males using a site downstream of the site used in females. The tra genes all contain a single TRA/TRA2 site in the male exon and a cluster of four to five sites in the male intron. However, overall the sex-specific intron sequences are poorly conserved in closely related blowflies. The most conserved regions are around the exon/intron junctions, the 3′ end of the intron and near the cluster of TRA/TRA2 sites. We propose a model for sex specific regulation of tra splicing that incorporates the conserved features identified in this study. In L. sericata embryos, the male tra transcript was first detected at around the time of cellular blastoderm formation. RNAi experiments showed that tra is required for female development in L. sericata and C. macellaria. The isolation of the tra gene from the New World screwworm fly C. hominivorax, a major livestock pest, will facilitate the development of a “male-only” strain for genetic control programs. PMID:23409170

  2. The hypoxic proteome is influenced by gene-specific changes in mRNA translation

    International Nuclear Information System (INIS)

    Koritzinsky, Marianne; Seigneuric, Renaud; Magagnin, Michael G.; Beucken, Twan van den; Lambin, Philippe; Wouters, Bradly G.

    2005-01-01

    Background and purpose: Hypoxia causes a rapid reduction in mRNA translation efficiency. This inhibition does not affect all mRNA species to the same extent and can therefore contribute significantly to hypoxia-induced differential protein expression. Our aim in this study was to characterize changes in gene expression during acute hypoxia and evaluate the contribution of regulation via mRNA translation on these changes. For each gene, the contribution of changes in mRNA abundance versus mRNA translation was determined. Materials and methods: DU145 prostate carcinoma cells were exposed to 4 h of hypoxia ( 2 ). Efficiently translated mRNAs were isolated by sedimentation through a sucrose gradient. Affymetrix microarray technology was used to evaluate both the transcriptional and translational contribution to gene expression. Results were validated by quantitative PCR. Results: One hundred and twenty genes were more than 4-fold upregulated by hypoxia in the efficiently translated fraction of mRNA, in comparison to only 76 genes at the level of transcription. Of the 50 genes demonstrating the largest changes in translation, 11 were found to be more than 2-fold over represented in the translated fraction in comparison to their overall transcriptional level. The gene with the highest translational contribution to its induction was CITED-2, which is a negative regulator of HIF-1 transcriptional activity. Conclusions: Gene-specific regulation of mRNA translation contributes significantly to differential gene expression during hypoxia

  3. Complimentary mechanisms of dual checkpoint blockade expand unique T-cell repertoires and activate adaptive anti-tumor immunity in triple-negative breast tumors

    Science.gov (United States)

    Wei, Junping; Yang, Xiao Yi; Lei, Gangjun; Wang, Tao; Liu, Cong-Xiao; Morse, Michael A.; Gouin, Kenneth; Knott, Simon R. V.; Hartman, Zachary C.

    2018-01-01

    ABSTRACT Triple-negative breast cancer (TNBC) is an aggressive and molecularly diverse breast cancer subtype typified by the presence of p53 mutations (∼80%), elevated immune gene signatures and neoantigen expression, as well as the presence of tumor infiltrating lymphocytes (TILs). As these factors are hypothesized to be strong immunologic prerequisites for the use of immune checkpoint blockade (ICB) antibodies, multiple clinical trials testing single ICBs have advanced to Phase III, with early indications of heterogeneous response rates of <20% to anti-PD1 and anti-PDL1 ICB. While promising, these modest response rates highlight the need for mechanistic studies to understand how different ICBs function, how their combination impacts functionality and efficacy, as well as what immunologic parameters predict efficacy to different ICBs regimens in TNBC. To address these issues, we tested anti-PD1 and anti-CTLA4 in multiple models of TNBC and found that their combination profoundly enhanced the efficacy of either treatment alone. We demonstrate that this efficacy is due to anti-CTLA4-driven expansion of an individually unique T-cell receptor (TCR) repertoire whose functionality is enhanced by both intratumoral Treg suppression and anti-PD1 blockade of tumor expressed PDL1. Notably, the individuality of the TCR repertoire was observed regardless of whether the tumor cells expressed a nonself antigen (ovalbumin) or if tumor-specific transgenic T-cells were transferred prior to sequencing. However, responsiveness was strongly correlated with systemic measures of tumor-specific T-cell and B-cell responses, which along with systemic assessment of TCR expansion, may serve as the most useful predictors for clinical responsiveness in future clinical trials of TNBC utilizing anti-PD1/anti-CTLA4 ICB. PMID:29721371

  4. Complimentary mechanisms of dual checkpoint blockade expand unique T-cell repertoires and activate adaptive anti-tumor immunity in triple-negative breast tumors.

    Science.gov (United States)

    Crosby, Erika J; Wei, Junping; Yang, Xiao Yi; Lei, Gangjun; Wang, Tao; Liu, Cong-Xiao; Agarwal, Pankaj; Korman, Alan J; Morse, Michael A; Gouin, Kenneth; Knott, Simon R V; Lyerly, H Kim; Hartman, Zachary C

    2018-01-01

    Triple-negative breast cancer (TNBC) is an aggressive and molecularly diverse breast cancer subtype typified by the presence of p53 mutations (∼80%), elevated immune gene signatures and neoantigen expression, as well as the presence of tumor infiltrating lymphocytes (TILs). As these factors are hypothesized to be strong immunologic prerequisites for the use of immune checkpoint blockade (ICB) antibodies, multiple clinical trials testing single ICBs have advanced to Phase III, with early indications of heterogeneous response rates of <20% to anti-PD1 and anti-PDL1 ICB. While promising, these modest response rates highlight the need for mechanistic studies to understand how different ICBs function, how their combination impacts functionality and efficacy, as well as what immunologic parameters predict efficacy to different ICBs regimens in TNBC. To address these issues, we tested anti-PD1 and anti-CTLA4 in multiple models of TNBC and found that their combination profoundly enhanced the efficacy of either treatment alone. We demonstrate that this efficacy is due to anti-CTLA4-driven expansion of an individually unique T-cell receptor (TCR) repertoire whose functionality is enhanced by both intratumoral Treg suppression and anti-PD1 blockade of tumor expressed PDL1. Notably, the individuality of the TCR repertoire was observed regardless of whether the tumor cells expressed a nonself antigen (ovalbumin) or if tumor-specific transgenic T-cells were transferred prior to sequencing. However, responsiveness was strongly correlated with systemic measures of tumor-specific T-cell and B-cell responses, which along with systemic assessment of TCR expansion, may serve as the most useful predictors for clinical responsiveness in future clinical trials of TNBC utilizing anti-PD1/anti-CTLA4 ICB.

  5. From inter-specific behavioural interactions to species distribution patterns along gradients of habitat heterogeneity.

    Science.gov (United States)

    Laiolo, Paola

    2013-01-01

    The strength of the behavioural processes associated with competitor coexistence may vary when different physical environments, and their biotic communities, come into contact, although empirical evidence of how interference varies across gradients of environmental complexity is still scarce in vertebrates. Here, I analyse how behavioural interactions and habitat selection regulate the local distribution of steppeland larks (Alaudidae) in a gradient from simple to heterogeneous agricultural landscapes in Spain, using crested lark Galerida cristata and Thekla lark G. theklae as study models. Galerida larks significantly partitioned by habitat but frequently co-occurred in heterogeneous environments. Irrespective of habitat divergence, however, the local densities of the two larks were negatively correlated, and the mechanisms beyond this pattern were investigated by means of playback experiments. When simulating the intrusion of the congener by broadcasting the species territorial calls, both larks responded with an aggressive response as intense with respect to warning and approach behaviour as when responding to the intrusion of a conspecific. However, birds promptly responded to playbacks only when congener territories were nearby, a phenomenon that points to learning as the mechanisms through which individuals finely tune their aggressive responses to the local competition levels. Heterospecifics occurred in closer proximity in diverse agro-ecosystems, possibly because of more abundant or diverse resources, and here engage in antagonistic interactions. The drop of species diversity associated with agricultural homogenisation is therefore likely to also bring about the disappearance of the behavioural repertoires associated with species interactions.

  6. Patterns of genetic diversity and differentiation in resistance gene clusters of two hybridizing European Populus species

    OpenAIRE

    Casey, Céline; Stölting, Kai N.; Barbará, Thelma; González-Martínez, Santiago C.; Lexer, Christian

    2015-01-01

    Resistance genes (R-genes) are essential for long-lived organisms such as forest trees, which are exposed to diverse herbivores and pathogens. In short-lived model species, R-genes have been shown to be involved in species isolation. Here, we studied more than 400 trees from two natural hybrid zones of the European Populus species Populus alba and Populus tremula for microsatellite markers located in three R-gene clusters, including one cluster situated in the incipient sex chromosome region....

  7. A pursuit of lineage-specific and niche-specific proteome features in the world of archaea.

    Science.gov (United States)

    Roy Chowdhury, Anindya; Dutta, Chitra

    2012-06-12

    Archaea evoke interest among researchers for two enigmatic characteristics -a combination of bacterial and eukaryotic components in their molecular architectures and an enormous diversity in their life-style and metabolic capabilities. Despite considerable research efforts, lineage- specific/niche-specific molecular features of the whole archaeal world are yet to be fully unveiled. The study offers the first large-scale in silico proteome analysis of all archaeal species of known genome sequences with a special emphasis on methanogenic and sulphur-metabolising archaea. Overall amino acid usage in archaea is dominated by GC-bias. But the environmental factors like oxygen requirement or thermal adaptation seem to play important roles in selection of residues with no GC-bias at the codon level. All methanogens, irrespective of their thermal/salt adaptation, show higher usage of Cys and have relatively acidic proteomes, while the proteomes of sulphur-metabolisers have higher aromaticity and more positive charges. Despite of exhibiting thermophilic life-style, korarchaeota possesses an acidic proteome. Among the distinct trends prevailing in COGs (Cluster of Orthologous Groups of proteins) distribution profiles, crenarchaeal organisms display higher intra-order variations in COGs repertoire, especially in the metabolic ones, as compared to euryarchaea. All methanogens are characterised by a presence of 22 exclusive COGs. Divergences in amino acid usage, aromaticity/charge profiles and COG repertoire among methanogens and sulphur-metabolisers, aerobic and anaerobic archaea or korarchaeota and nanoarchaeota, as elucidated in the present study, point towards the presence of distinct molecular strategies for niche specialization in the archaeal world.

  8. A pursuit of lineage-specific and niche-specific proteome features in the world of archaea

    Directory of Open Access Journals (Sweden)

    Roy Chowdhury Anindya

    2012-06-01

    Full Text Available Abstract Background Archaea evoke interest among researchers for two enigmatic characteristics –a combination of bacterial and eukaryotic components in their molecular architectures and an enormous diversity in their life-style and metabolic capabilities. Despite considerable research efforts, lineage- specific/niche-specific molecular features of the whole archaeal world are yet to be fully unveiled. The study offers the first large-scale in silico proteome analysis of all archaeal species of known genome sequences with a special emphasis on methanogenic and sulphur-metabolising archaea. Results Overall amino acid usage in archaea is dominated by GC-bias. But the environmental factors like oxygen requirement or thermal adaptation seem to play important roles in selection of residues with no GC-bias at the codon level. All methanogens, irrespective of their thermal/salt adaptation, show higher usage of Cys and have relatively acidic proteomes, while the proteomes of sulphur-metabolisers have higher aromaticity and more positive charges. Despite of exhibiting thermophilic life-style, korarchaeota possesses an acidic proteome. Among the distinct trends prevailing in COGs (Cluster of Orthologous Groups of proteins distribution profiles, crenarchaeal organisms display higher intra-order variations in COGs repertoire, especially in the metabolic ones, as compared to euryarchaea. All methanogens are characterised by a presence of 22 exclusive COGs. Conclusions Divergences in amino acid usage, aromaticity/charge profiles and COG repertoire among methanogens and sulphur-metabolisers, aerobic and anaerobic archaea or korarchaeota and nanoarchaeota, as elucidated in the present study, point towards the presence of distinct molecular strategies for niche specialization in the archaeal world.

  9. Discovery of cancer common and specific driver gene sets

    Science.gov (United States)

    2017-01-01

    Abstract Cancer is known as a disease mainly caused by gene alterations. Discovery of mutated driver pathways or gene sets is becoming an important step to understand molecular mechanisms of carcinogenesis. However, systematically investigating commonalities and specificities of driver gene sets among multiple cancer types is still a great challenge, but this investigation will undoubtedly benefit deciphering cancers and will be helpful for personalized therapy and precision medicine in cancer treatment. In this study, we propose two optimization models to de novo discover common driver gene sets among multiple cancer types (ComMDP) and specific driver gene sets of one certain or multiple cancer types to other cancers (SpeMDP), respectively. We first apply ComMDP and SpeMDP to simulated data to validate their efficiency. Then, we further apply these methods to 12 cancer types from The Cancer Genome Atlas (TCGA) and obtain several biologically meaningful driver pathways. As examples, we construct a common cancer pathway model for BRCA and OV, infer a complex driver pathway model for BRCA carcinogenesis based on common driver gene sets of BRCA with eight cancer types, and investigate specific driver pathways of the liquid cancer lymphoblastic acute myeloid leukemia (LAML) versus other solid cancer types. In these processes more candidate cancer genes are also found. PMID:28168295

  10. Identification of species- and tissue-specific proteins using proteomic strategy

    Science.gov (United States)

    Chernukha, I. M.; Vostrikova, N. L.; Kovalev, L. I.; Shishkin, S. S.; Kovaleva, M. A.; Manukhin, Y. S.

    2017-09-01

    Proteomic technologies have proven to be very effective for detecting biochemical changes in meat products, such as changes in tissue- and species-specific proteins. In the tissues of cattle, pig, horse and camel M. longissimus dorsi both tissue- and species specific proteins were detected using two dimensional electrophoresis. Species-specific isoforms of several muscle proteins were also identified. The identified and described proteins of cattle, pig, horse and camel skeletal muscles (including mass spectra of the tryptic peptides) were added to the national free access database “Muscle organ proteomics”. This research has enabled the development of new highly sensitive technologies for meat product quality control against food fraud.

  11. Linking experiences with emotions and the development of interpretive repertoires

    Science.gov (United States)

    McRae, Norah I.

    2010-03-01

    In this paper I consider the case of one student, Todd Alexander, through analyzing the transcripts of his interviews between him and his teacher (Wolff-Michael Roth). I examine the role that emotions play in the development of the interpretive repertoires that Todd employed as he talked about his scientific and his religious beliefs. I identify how lived experiences support the development of emotions and what educational conditions are necessary to allow for appropriate lived experiences. In so doing we might be able to support educational conditions that result in interpretive repertoires that allow for acceptance of multiple perspectives with a moral grounding, leading to students who are well positioned to be valuable contributors to society.

  12. Constraints on genome dynamics revealed from gene distribution among the Ralstonia solanacearum species.

    Directory of Open Access Journals (Sweden)

    Pierre Lefeuvre

    Full Text Available Because it is suspected that gene content may partly explain host adaptation and ecology of pathogenic bacteria, it is important to study factors affecting genome composition and its evolution. While recent genomic advances have revealed extremely large pan-genomes for some bacterial species, it remains difficult to predict to what extent gene pool is accessible within or transferable between populations. As genomes bear imprints of the history of the organisms, gene distribution pattern analyses should provide insights into the forces and factors at play in the shaping and maintaining of bacterial genomes. In this study, we revisited the data obtained from a previous CGH microarrays analysis in order to assess the genomic plasticity of the R. solanacearum species complex. Gene distribution analyses demonstrated the remarkably dispersed genome of R. solanacearum with more than half of the genes being accessory. From the reconstruction of the ancestral genomes compositions, we were able to infer the number of gene gain and loss events along the phylogeny. Analyses of gene movement patterns reveal that factors associated with gene function, genomic localization and ecology delineate gene flow patterns. While the chromosome displayed lower rates of movement, the megaplasmid was clearly associated with hot-spots of gene gain and loss. Gene function was also confirmed to be an essential factor in gene gain and loss dynamics with significant differences in movement patterns between different COG categories. Finally, analyses of gene distribution highlighted possible highways of horizontal gene transfer. Due to sampling and design bias, we can only speculate on factors at play in this gene movement dynamic. Further studies examining precise conditions that favor gene transfer would provide invaluable insights in the fate of bacteria, species delineation and the emergence of successful pathogens.

  13. Species-Specific Responses of Juvenile Rockfish to Elevated pCO2: From Behavior to Genomics.

    Directory of Open Access Journals (Sweden)

    Scott L Hamilton

    Full Text Available In the California Current ecosystem, global climate change is predicted to trigger large-scale changes in ocean chemistry within this century. Ocean acidification-which occurs when increased levels of atmospheric CO2 dissolve into the ocean-is one of the biggest potential threats to marine life. In a coastal upwelling system, we compared the effects of chronic exposure to low pH (elevated pCO2 at four treatment levels (i.e., pCO2 = ambient [500], moderate [750], high [1900], and extreme [2800 μatm] on behavior, physiology, and patterns of gene expression in white muscle tissue of juvenile rockfish (genus Sebastes, integrating responses from the transcriptome to the whole organism level. Experiments were conducted simultaneously on two closely related species that both inhabit kelp forests, yet differ in early life history traits, to compare high-CO2 tolerance among species. Our findings indicate that these congeners express different sensitivities to elevated CO2 levels. Copper rockfish (S. caurinus exhibited changes in behavioral lateralization, reduced critical swimming speed, depressed aerobic scope, changes in metabolic enzyme activity, and increases in the expression of transcription factors and regulatory genes at high pCO2 exposure. Blue rockfish (S. mystinus, in contrast, showed no significant changes in behavior, swimming physiology, or aerobic capacity, but did exhibit significant changes in the expression of muscle structural genes as a function of pCO2, indicating acclimatization potential. The capacity of long-lived, late to mature, commercially important fish to acclimatize and adapt to changing ocean chemistry over the next 50-100 years is likely dependent on species-specific physiological tolerances.

  14. Comparative Analysis of Fruit Metabolites and Pungency Candidate Genes Expression between Bhut Jolokia and Other Capsicum Species.

    Directory of Open Access Journals (Sweden)

    Sarpras M

    Full Text Available Bhut jolokia, commonly known as Ghost chili, a native Capsicum species found in North East India was recorded as the naturally occurring hottest chili in the world by the Guinness Book of World Records in 2006. Although few studies have reported variation in pungency content of this particular species, no study till date has reported detailed expression analysis of candidate genes involved in capsaicinoids (pungency biosynthesis pathway and other fruit metabolites. Therefore, the present study was designed to evaluate the diversity of fruit morphology, fruiting habit, capsaicinoids and other metabolite contents in 136 different genotypes mainly collected from North East India. Significant intra and inter-specific variations for fruit morphological traits, fruiting habits and 65 fruit metabolites were observed in the collected Capsicum germplasm belonging to three Capsicum species i.e., Capsicum chinense (Bhut jolokia, 63 accessions, C. frutescens (17 accessions and C. annuum (56 accessions. The pungency level, measured in Scoville Heat Unit (SHU and antioxidant activity measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH free radical scavenging assay showed maximum levels in C. chinense accessions followed by C. frutescens accessions, while C. annuum accessions showed the lowest value for both the traits. The number of different fruit metabolites detected did not vary significantly among the different species but the metabolite such as benzoic acid hydroxyl esters identified in large percentage in majority of C. annuum genotypes was totally absent in the C. chinense genotypes and sparingly present in few genotypes of C. frutescens. Significant correlations were observed between fruit metabolites capsaicin, dihydrocapsaicin, hexadecanoic acid, cyclopentane, α-tocopherol and antioxidant activity. Furthermore, comparative expression analysis (through qRT-PCR of candidate genes involved in capsaicinoid biosynthesis pathway revealed many fold higher

  15. Comparative Analysis of Fruit Metabolites and Pungency Candidate Genes Expression between Bhut Jolokia and Other Capsicum Species.

    Science.gov (United States)

    M, Sarpras; Gaur, Rashmi; Sharma, Vineet; Chhapekar, Sushil Satish; Das, Jharna; Kumar, Ajay; Yadava, Satish Kumar; Nitin, Mukesh; Brahma, Vijaya; Abraham, Suresh K; Ramchiary, Nirala

    2016-01-01

    Bhut jolokia, commonly known as Ghost chili, a native Capsicum species found in North East India was recorded as the naturally occurring hottest chili in the world by the Guinness Book of World Records in 2006. Although few studies have reported variation in pungency content of this particular species, no study till date has reported detailed expression analysis of candidate genes involved in capsaicinoids (pungency) biosynthesis pathway and other fruit metabolites. Therefore, the present study was designed to evaluate the diversity of fruit morphology, fruiting habit, capsaicinoids and other metabolite contents in 136 different genotypes mainly collected from North East India. Significant intra and inter-specific variations for fruit morphological traits, fruiting habits and 65 fruit metabolites were observed in the collected Capsicum germplasm belonging to three Capsicum species i.e., Capsicum chinense (Bhut jolokia, 63 accessions), C. frutescens (17 accessions) and C. annuum (56 accessions). The pungency level, measured in Scoville Heat Unit (SHU) and antioxidant activity measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay showed maximum levels in C. chinense accessions followed by C. frutescens accessions, while C. annuum accessions showed the lowest value for both the traits. The number of different fruit metabolites detected did not vary significantly among the different species but the metabolite such as benzoic acid hydroxyl esters identified in large percentage in majority of C. annuum genotypes was totally absent in the C. chinense genotypes and sparingly present in few genotypes of C. frutescens. Significant correlations were observed between fruit metabolites capsaicin, dihydrocapsaicin, hexadecanoic acid, cyclopentane, α-tocopherol and antioxidant activity. Furthermore, comparative expression analysis (through qRT-PCR) of candidate genes involved in capsaicinoid biosynthesis pathway revealed many fold higher expression of

  16. Supplementary Material for: Global expression differences and tissue specific expression differences in rice evolution result in two contrasting types of differentially expressed genes

    KAUST Repository

    Horiuchi, Youko; Harushima, Yoshiaki; Fujisawa, Hironori; Mochizuki, Takako; Fujita, Masahiro; Ohyanagi, Hajime; Kurata, Nori

    2015-01-01

    Abstract Background Since the development of transcriptome analysis systems, many expression evolution studies characterized evolutionary forces acting on gene expression, without explicit discrimination between global expression differences and tissue specific expression differences. However, different types of gene expression alteration should have different effects on an organism, the evolutionary forces that act on them might be different, and different types of genes might show different types of differential expression between species. To confirm this, we studied differentially expressed (DE) genes among closely related groups that have extensive gene expression atlases, and clarified characteristics of different types of DE genes including the identification of regulating loci for differential expression using expression quantitative loci (eQTL) analysis data. Results We detected differentially expressed (DE) genes between rice subspecies in five homologous tissues that were verified using japonica and indica transcriptome atlases in public databases. Using the transcriptome atlases, we classified DE genes into two types, global DE genes and changed-tissues DE genes. Global type DE genes were not expressed in any tissues in the atlas of one subspecies, however changed-tissues type DE genes were expressed in both subspecies with different tissue specificity. For the five tissues in the two japonica-indica combinations, 4.6 ± 0.8 and 5.9 ± 1.5 % of highly expressed genes were global and changed-tissues DE genes, respectively. Changed-tissues DE genes varied in number between tissues, increasing linearly with the abundance of tissue specifically expressed genes in the tissue. Molecular evolution of global DE genes was rapid, unlike that of changed-tissues DE genes. Based on gene ontology, global and changed-tissues DE genes were different, having no common GO terms. Expression differences of most global DE genes were regulated by cis

  17. The MB2 gene family of Plasmodium species has a unique combination of S1 and GTP-binding domains

    Directory of Open Access Journals (Sweden)

    Ogunjumo Oluwasanmi

    2004-06-01

    Full Text Available Abstract Background Identification and characterization of novel Plasmodium gene families is necessary for developing new anti-malarial therapeutics. The products of the Plasmodium falciparum gene, MB2, were shown previously to have a stage-specific pattern of subcellular localization and proteolytic processing. Results Genes homologous to MB2 were identified in five additional parasite species, P. knowlesi, P. gallinaceum, P. berghei, P. yoelii, and P. chabaudi. Sequence comparisons among the MB2 gene products reveal amino acid conservation of structural features, including putative S1 and GTP-binding domains, and putative signal peptides and nuclear localization signals. Conclusions The combination of domains is unique to this gene family and indicates that MB2 genes comprise a novel family and therefore may be a good target for drug development.

  18. The MB2 gene family of Plasmodium species has a unique combination of S1 and GTP-binding domains

    Science.gov (United States)

    Romero, Lisa C; Nguyen, Thanh V; Deville, Benoit; Ogunjumo, Oluwasanmi; James, Anthony A

    2004-01-01

    Background Identification and characterization of novel Plasmodium gene families is necessary for developing new anti-malarial therapeutics. The products of the Plasmodium falciparum gene, MB2, were shown previously to have a stage-specific pattern of subcellular localization and proteolytic processing. Results Genes homologous to MB2 were identified in five additional parasite species, P. knowlesi, P. gallinaceum, P. berghei, P. yoelii, and P. chabaudi. Sequence comparisons among the MB2 gene products reveal amino acid conservation of structural features, including putative S1 and GTP-binding domains, and putative signal peptides and nuclear localization signals. Conclusions The combination of domains is unique to this gene family and indicates that MB2 genes comprise a novel family and therefore may be a good target for drug development. PMID:15222903

  19. Emerging functions of ribosomal proteins in gene-specific transcription and translation

    International Nuclear Information System (INIS)

    Lindstroem, Mikael S.

    2009-01-01

    Ribosomal proteins have remained highly conserved during evolution presumably reflecting often critical functions in ribosome biogenesis or mature ribosome function. In addition, several ribosomal proteins possess distinct extra-ribosomal functions in apoptosis, DNA repair and transcription. An increasing number of ribosomal proteins have been shown to modulate the trans-activation function of important regulatory proteins such as NF-κB, p53, c-Myc and nuclear receptors. Furthermore, a subset of ribosomal proteins can bind directly to untranslated regions of mRNA resulting in transcript-specific translational control outside of the ribosome itself. Collectively, these findings suggest that ribosomal proteins may have a wider functional repertoire within the cell than previously thought. The future challenge is to identify and validate these novel functions in the background of an often essential primary function in ribosome biogenesis and cell growth.

  20. A Comparison of the Basic Song Repertoire of Vocal/Choral and Instrumental Music Education Majors.

    Science.gov (United States)

    Prickett, Carol A.; Bridges, Madeline S.

    2000-01-01

    Explores whether the basic song repertoire of vocal/choral music education majors is significantly better than instrumental music education majors. Participants attempted to identify 25 standard songs. Reveals no significant difference between the two groups, indicating that neither had developed a strong repertoire of songs. (CMK)

  1. Engineering Specificity and Function of Therapeutic Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Jenny L. McGovern

    2017-11-01

    Full Text Available Adoptive therapy with polyclonal regulatory T cells (Tregs has shown efficacy in suppressing detrimental immune responses in experimental models of autoimmunity and transplantation. The lack of specificity is a potential limitation of Treg therapy, as studies in mice have demonstrated that specificity can enhance the therapeutic potency of Treg. We will discuss that vectors encoding T cell receptors or chimeric antigen receptors provide an efficient gene-transfer platform to reliably produce Tregs of defined antigen specificity, thus overcoming the considerable difficulties of isolating low-frequency, antigen-specific cells that may be present in the natural Treg repertoire. The recent observations that Tregs can polarize into distinct lineages similar to the Th1, Th2, and Th17 subsets described for conventional T helper cells raise the possibility that Th1-, Th2-, and Th17-driven pathology may require matching Treg subsets for optimal therapeutic efficacy. In the future, genetic engineering may serve not only to enforce FoxP3 expression and a stable Treg phenotype but it may also enable the expression of particular transcription factors that drive differentiation into defined Treg subsets. Together, established and recently developed gene transfer and editing tools provide exciting opportunities to produce tailor-made antigen-specific Treg products with defined functional activities.

  2. Development of a Rickettsia bellii-Specific TaqMan Assay Targeting the Citrate Synthase Gene.

    Science.gov (United States)

    Hecht, Joy A; Allerdice, Michelle E J; Krawczak, Felipe S; Labruna, Marcelo B; Paddock, Christopher D; Karpathy, Sandor E

    2016-11-01

    Rickettsia bellii is a rickettsial species of unknown pathogenicity that infects argasid and ixodid ticks throughout the Americas. Many molecular assays used to detect spotted fever group (SFG) Rickettsia species do not detect R. bellii, so that infection with this bacterium may be concealed in tick populations when assays are used that screen specifically for SFG rickettsiae. We describe the development and validation of a R. bellii-specific, quantitative, real-time PCR TaqMan assay that targets a segment of the citrate synthase (gltA) gene. The specificity of this assay was validated against a panel of DNA samples that included 26 species of Rickettsia, Orientia, Ehrlichia, Anaplasma, and Bartonella, five samples of tick and human DNA, and DNA from 20 isolates of R. bellii, including 11 from North America and nine from South America. A R. bellii control plasmid was constructed, and serial dilutions of the plasmid were used to determine the limit of detection of the assay to be one copy per 4 µl of template DNA. This assay can be used to better determine the role of R. bellii in the epidemiology of tick-borne rickettsioses in the Western Hemisphere. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.

  3. Species limits and relationships within Otidea inferred from multiple gene phylogenies

    NARCIS (Netherlands)

    Hansen, K.; Olariaga, I.

    2015-01-01

    The genus Otidea is one of the more conspicuous members of the Pyronemataceae, with high species diversity in hemiboreal and boreal forests. The genus is morphologically coherent and in previous higher-level multi-gene analyses it formed a highly supported monophyletic group. Species delimitation

  4. Computational identification of strain-, species- and genus-specific proteins

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    Thiagarajan Rathi

    2005-11-01

    Full Text Available Abstract Background The identification of unique proteins at different taxonomic levels has both scientific and practical value. Strain-, species- and genus-specific proteins can provide insight into the criteria that define an organism and its relationship with close relatives. Such proteins can also serve as taxon-specific diagnostic targets. Description A pipeline using a combination of computational and manual analyses of BLAST results was developed to identify strain-, species-, and genus-specific proteins and to catalog the closest sequenced relative for each protein in a proteome. Proteins encoded by a given strain are preliminarily considered to be unique if BLAST, using a comprehensive protein database, fails to retrieve (with an e-value better than 0.001 any protein not encoded by the query strain, species or genus (for strain-, species- and genus-specific proteins respectively, or if BLAST, using the best hit as the query (reverse BLAST, does not retrieve the initial query protein. Results are manually inspected for homology if the initial query is retrieved in the reverse BLAST but is not the best hit. Sequences unlikely to retrieve homologs using the default BLOSUM62 matrix (usually short sequences are re-tested using the PAM30 matrix, thereby increasing the number of retrieved homologs and increasing the stringency of the search for unique proteins. The above protocol was used to examine several food- and water-borne pathogens. We find that the reverse BLAST step filters out about 22% of proteins with homologs that would otherwise be considered unique at the genus and species levels. Analysis of the annotations of unique proteins reveals that many are remnants of prophage proteins, or may be involved in virulence. The data generated from this study can be accessed and further evaluated from the CUPID (Core and Unique Protein Identification system web site (updated semi-annually at http://pir.georgetown.edu/cupid. Conclusion CUPID

  5. Conservation of transcription factor binding events predicts gene expression across species

    Science.gov (United States)

    Hemberg, Martin; Kreiman, Gabriel

    2011-01-01

    Recent technological advances have made it possible to determine the genome-wide binding sites of transcription factors (TFs). Comparisons across species have suggested a relatively low degree of evolutionary conservation of experimentally defined TF binding events (TFBEs). Using binding data for six different TFs in hepatocytes and embryonic stem cells from human and mouse, we demonstrate that evolutionary conservation of TFBEs within orthologous proximal promoters is closely linked to function, defined as expression of the target genes. We show that (i) there is a significantly higher degree of conservation of TFBEs when the target gene is expressed in both species; (ii) there is increased conservation of binding events for groups of TFs compared to individual TFs; and (iii) conserved TFBEs have a greater impact on the expression of their target genes than non-conserved ones. These results link conservation of structural elements (TFBEs) to conservation of function (gene expression) and suggest a higher degree of functional conservation than implied by previous studies. PMID:21622661

  6. The evolution of pepsinogen C genes in vertebrates: duplication, loss and functional diversification.

    Directory of Open Access Journals (Sweden)

    Luís Filipe Costa Castro

    Full Text Available BACKGROUND: Aspartic proteases comprise a large group of enzymes involved in peptide proteolysis. This collection includes prominent enzymes globally categorized as pepsins, which are derived from pepsinogen precursors. Pepsins are involved in gastric digestion, a hallmark of vertebrate physiology. An important member among the pepsinogens is pepsinogen C (Pgc. A particular aspect of Pgc is its apparent single copy status, which contrasts with the numerous gene copies found for example in pepsinogen A (Pga. Although gene sequences with similarity to Pgc have been described in some vertebrate groups, no exhaustive evolutionary framework has been considered so far. METHODOLOGY/PRINCIPAL FINDINGS: By combining phylogenetics and genomic analysis, we find an unexpected Pgc diversity in the vertebrate sub-phylum. We were able to reconstruct gene duplication timings relative to the divergence of major vertebrate clades. Before tetrapod divergence, a single Pgc gene tandemly expanded to produce two gene lineages (Pgbc and Pgc2. These have been differentially retained in various classes. Accordingly, we find Pgc2 in sauropsids, amphibians and marsupials, but not in eutherian mammals. Pgbc was retained in amphibians, but duplicated in the ancestor of amniotes giving rise to Pgb and Pgc1. The latter was retained in mammals and probably in reptiles and marsupials but not in birds. Pgb was kept in all of the amniote clade with independent episodes of loss in some mammalian species. Lineage specific expansions of Pgc2 and Pgbc have also occurred in marsupials and amphibians respectively. We find that teleost and tetrapod Pgc genes reside in distinct genomic regions hinting at a possible translocation. CONCLUSIONS: We conclude that the repertoire of Pgc genes is larger than previously reported, and that tandem duplications have modelled the history of Pgc genes. We hypothesize that gene expansion lead to functional divergence in tetrapods, coincident with the

  7. Genomic Resources of Three Pulsatilla Species Reveal Evolutionary Hotspots, Species-Specific Sites and Variable Plastid Structure in the Family Ranunculaceae.

    Science.gov (United States)

    Szczecińska, Monika; Sawicki, Jakub

    2015-09-15

    The European continent is presently colonized by nine species of the genus Pulsatilla, five of which are encountered only in mountainous regions of southwest and south-central Europe. The remaining four species inhabit lowlands in the north-central and eastern parts of the continent. Most plants of the genus Pulsatilla are rare and endangered, which is why most research efforts focused on their biology, ecology and hybridization. The objective of this study was to develop genomic resources, including complete plastid genomes and nuclear rRNA clusters, for three sympatric Pulsatilla species that are most commonly found in Central Europe. The results will supply valuable information about genetic variation, which can be used in the process of designing primers for population studies and conservation genetics research. The complete plastid genomes together with the nuclear rRNA cluster can serve as a useful tool in hybridization studies. Six complete plastid genomes and nuclear rRNA clusters were sequenced from three species of Pulsatilla using the Illumina sequencing technology. Four junctions between single copy regions and inverted repeats and junctions between the identified locally-collinear blocks (LCB) were confirmed by Sanger sequencing. Pulsatilla genomes of 120 unique genes had a total length of approximately 161-162 kb, and 21 were duplicated in the inverted repeats (IR) region. Comparative plastid genomes of newly-sequenced Pulsatilla and the previously-identified plastomes of Aconitum and Ranunculus species belonging to the family Ranunculaceae revealed several variations in the structure of the genome, but the gene content remained constant. The nuclear rRNA cluster (18S-ITS1-5.8S-ITS2-26S) of studied Pulsatilla species is 5795 bp long. Among five analyzed regions of the rRNA cluster, only Internal Transcribed Spacer 2 (ITS2) enabled the molecular delimitation of closely-related Pulsatilla patens and Pulsatilla vernalis. The determination of complete

  8. From everyday communicative figurations to rigorous audience news repertoires

    DEFF Research Database (Denmark)

    Kobbernagel, Christian; Schrøder, Kim Christian

    2016-01-01

    In the last couple of decades there has been an unprecedented explosion of news media platforms and formats, as a succession of digital and social media have joined the ranks of legacy media. We live in a ‘hybrid media system’ (Chadwick, 2013), in which people build their cross-media news...... repertoires from the ensemble of old and new media available. This article presents an innovative mixed-method approach with considerable explanatory power to the exploration of patterns of news media consumption. This approach tailors Q-methodology in the direction of a qualitative study of news consumption......, in which a card sorting exercise serves to translate the participants’ news media preferences into a form that enables the researcher to undertake a rigorous factor-analytical construction of their news consumption repertoires. This interpretive, factor-analytical procedure, which results in the building...

  9. Organ-specific gene expression: the bHLH protein Sage provides tissue specificity to Drosophila FoxA.

    Science.gov (United States)

    Fox, Rebecca M; Vaishnavi, Aria; Maruyama, Rika; Andrew, Deborah J

    2013-05-01

    FoxA transcription factors play major roles in organ-specific gene expression, regulating, for example, glucagon expression in the pancreas, GLUT2 expression in the liver, and tyrosine hydroxylase expression in dopaminergic neurons. Organ-specific gene regulation by FoxA proteins is achieved through cooperative regulation with a broad array of transcription factors with more limited expression domains. Fork head (Fkh), the sole Drosophila FoxA family member, is required for the development of multiple distinct organs, yet little is known regarding how Fkh regulates tissue-specific gene expression. Here, we characterize Sage, a bHLH transcription factor expressed exclusively in the Drosophila salivary gland (SG). We show that Sage is required for late SG survival and normal tube morphology. We find that many Sage targets, identified by microarray analysis, encode SG-specific secreted cargo, transmembrane proteins, and the enzymes that modify these proteins. We show that both Sage and Fkh are required for the expression of Sage target genes, and that co-expression of Sage and Fkh is sufficient to drive target gene expression in multiple cell types. Sage and Fkh drive expression of the bZip transcription factor Senseless (Sens), which boosts expression of Sage-Fkh targets, and Sage, Fkh and Sens colocalize on SG chromosomes. Importantly, expression of Sage-Fkh target genes appears to simply add to the tissue-specific gene expression programs already established in other cell types, and Sage and Fkh cannot alter the fate of most embryonic cell types even when expressed early and continuously.

  10. TAL effectors and the executor R genes.

    Science.gov (United States)

    Zhang, Junli; Yin, Zhongchao; White, Frank

    2015-01-01

    Transcription activator-like (TAL) effectors are bacterial type III secretion proteins that function as transcription factors in plants during Xanthomonas/plant interactions, conditioning either host susceptibility and/or host resistance. Three types of TAL effector associated resistance (R) genes have been characterized-recessive, dominant non-transcriptional, and dominant TAL effector-dependent transcriptional based resistance. Here, we discuss the last type of R genes, whose functions are dependent on direct TAL effector binding to discrete effector binding elements in the promoters. Only five of the so-called executor R genes have been cloned, and commonalities are not clear. We have placed the protein products in two groups for conceptual purposes. Group 1 consists solely of the protein from pepper, BS3, which is predicted to have catalytic function on the basis of homology to a large conserved protein family. Group 2 consists of BS4C-R, XA27, XA10, and XA23, all of which are relatively short proteins from pepper or rice with multiple potential transmembrane domains. Group 2 members have low sequence similarity to proteins of unknown function in closely related species. Firm predictions await further experimentation on these interesting new members to the R gene repertoire, which have potential broad application in new strategies for disease resistance.

  11. TAL effectors and the executor R genes

    Directory of Open Access Journals (Sweden)

    Junli eZhang

    2015-08-01

    Full Text Available Transcription activation-like (TAL effectors are bacterial type III secretion proteins that function as transcription factors in plants during Xanthomonas/plant interactions, conditioning either host susceptibility and/or host resistance. Three types of TAL effector associated resistance (R genes have been characterized - recessive, dominant non-transcriptional and dominant TAL effector-dependent transcriptional based resistance. Here, we discuss the last type of R genes, whose functions are dependent on direct TAL effector binding to discrete effector binding elements in the promoters. Only five of the so-called executor R genes have been cloned, and commonalities are not clear. We have placed the protein products in two groups for conceptual purposes. Group 1 consists solely of the protein from pepper, BS3, which is predicted to have catalytic function on the basis of homology to a large conserved protein family. Group 2 consists of BS4C-R, XA27, XA10, and XA23, all of which are relatively short proteins from pepper or rice with multiple potential transmembrane domains. Group 2 members have low sequence similarity to proteins of unknown function in closely related species. Firm predictions await further experimentation on these interesting new members to the R gene repertoire, which have potential broad application in new strategies for disease resistance.

  12. Uncovering iron regulation with species-specific transcriptome patterns in Atlantic and coho salmon during a Caligus rogercresseyi infestation.

    Science.gov (United States)

    Valenzuela-Muñoz, V; Boltaña, S; Gallardo-Escárate, C

    2017-09-01

    Salmon species cultured in Chile evidence different levels of susceptibility to the sea louse Caligus rogercresseyi. These differences have mainly been associated with specific immune responses. Moreover, iron regulation seems to be an important mechanism to confer immunity during the host infestation. This response called nutritional immunity has been described in bacterial infections, despite that no comprehensive studies involving in marine ectoparasites infestation have been reported. With this aim, we analysed the transcriptome profiles of Atlantic and coho salmon infected with C. rogercresseyi to evidence modulation of the iron metabolism as a proxy of nutritional immune responses. Whole transcriptome sequencing was performed in samples of skin and head kidney from Atlantic and coho salmon infected with sea lice. RNA-seq analyses revealed significant upregulation of transcripts in both salmon species at 7 and 14 dpi in skin and head kidney, respectively. However, iron regulation transcripts were differentially modulated, evidencing species-specific expression profiles. Genes related to heme degradation and iron transport such as hepcidin, transferrin and haptoglobin were primary upregulated in Atlantic salmon; meanwhile, in coho salmon, genes associated with heme biosynthesis were strongly transcribed. In summary, Atlantic salmon, which are more susceptible to infestation, presented molecular mechanisms to deplete cellular iron availability, suggesting putative mechanisms of nutritional immunity. In contrast, resistant coho salmon were less affected by sea lice, mainly activating pro-inflammatory mechanisms to cope with infestation. © 2017 John Wiley & Sons Ltd.

  13. Genome-wide identification of 52 cytochrome P450 (CYP) genes in the copepod Tigriopus japonicus and their B[α]P-induced expression patterns.

    Science.gov (United States)

    Han, Jeonghoon; Kim, Duck-Hyun; Kim, Hui-Su; Nelson, David R; Lee, Jae-Seong

    2017-09-01

    Cytochrome P450s (CYPs) are enzymes with a heme-binding domain that are found in all living organisms. CYP enzymes have important roles associated with detoxification of xenobiotics and endogenous compounds (e.g. steroids, fatty acids, and hormones). Although CYP enzymes have been reported in several invertebrates, including insects, little is known about copepod CYPs. Here, we identified the entire repertoire of CYP genes (n=52) from whole genome and transcriptome sequences of the benthic copepod Tigriopus japonicus, including a tandem duplication (CYP3026A3, CYP3026A4, CYP3026A5), and examined patterns of gene expression over various developmental stages and in response to benzo[α]pyrene (B[α]P) exposure. Through phylogenetic analysis, the 52 T. japonicus CYP genes were assigned to five distinct clans: CYP2 (22 genes), CYP3 (19 genes), CYP4 (two genes), CYP20 (one gene), and mitochondrial (eight genes). Developmental stage and gender-specific expression patterns of the 52 T. japonicus CYPs were analyzed. CYP3022A1 was constitutively expressed during all developmental stages. CYP genes in clans 2 and 3 were induced in response to B[α]P, suggesting that these differentially modulated CYP transcripts are likely involved in defense against exposure to B[α]P and other pollutants. This study enhances our understanding of the repertoire of CYP genes in copepods and of their potential role in development and detoxification in copepods. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. The evolution of highly variable immunity genes across a passerine bird radiation.

    Science.gov (United States)

    O'Connor, E A; Strandh, M; Hasselquist, D; Nilsson, J-Å; Westerdahl, H

    2016-02-01

    To survive, individuals must be able to recognize and eliminate pathogens. The genes of the major histocompatibility complex (MHC) play an essential role in this process in vertebrates as their diversity affects the repertoire of pathogens that can be recognized by the immune system. Emerging evidence suggests that birds within the parvorder Passerida possess an exceptionally high number of MHC genes. However, this has yet to be directly investigated using a consistent framework, and the question of how this MHC diversity has evolved has not been addressed. We used next-generation sequencing to investigate how MHC class I gene copy number and sequence diversity varies across the Passerida radiation using twelve species chosen to represent the phylogenetic range of this group. Additionally, we performed phylogenetic analyses on this data to identify, for the first time, the evolutionary model that best describes how MHC class I gene diversity has evolved within Passerida. We found evidence of multiple MHC class I genes in every family tested, with an extremely broad range in gene copy number across Passerida. There was a strong phylogenetic signal in MHC gene copy number and diversity, and these traits appear to have evolved through a process of Brownian motion in the species studied, that is following the pattern of genetic drift or fluctuating selection, as opposed to towards a single optimal value or through evolutionary 'bursts'. By characterizing MHC class I gene diversity across Passerida in a systematic framework, this study provides a first step towards understanding this huge variation. © 2016 John Wiley & Sons Ltd.

  15. Comparative transcriptome analysis and identification of candidate effectors in two related rust species (Gymnosporangium yamadae and Gymnosporangium asiaticum).

    Science.gov (United States)

    Tao, Si-Qi; Cao, Bin; Tian, Cheng-Ming; Liang, Ying-Mei

    2017-08-23

    Rust fungi constitute the largest group of plant fungal pathogens. However, a paucity of data, including genomic sequences, transcriptome sequences, and associated molecular markers, hinders the development of inhibitory compounds and prevents their analysis from an evolutionary perspective. Gymnosporangium yamadae and G. asiaticum are two closely related rust fungal species, which are ecologically and economically important pathogens that cause apple rust and pear rust, respectively, proved to be devastating to orchards. In this study, we investigated the transcriptomes of these two Gymnosporangium species during the telial stage of their lifecycles. The aim of this study was to understand the evolutionary patterns of these two related fungi and to identify genes that developed by selection. The transcriptomes of G. yamadae and G. asiaticum were generated from a mixture of RNA from three biological replicates of each species. We obtained 49,318 and 54,742 transcripts, with N50 values of 1957 and 1664, for G. yamadae and G. asiaticum, respectively. We also identified a repertoire of candidate effectors and other gene families associated with pathogenicity. A total of 4947 pairs of putative orthologues between the two species were identified. Estimation of the non-synonymous/synonymous substitution rate ratios for these orthologues identified 116 pairs with Ka/Ks values greater than1 that are under positive selection and 170 pairs with Ka/Ks values of 1 that are under neutral selection, whereas the remaining 4661 genes are subjected to purifying selection. We estimate that the divergence time between the two species is approximately 5.2 Mya. This study constitutes a de novo assembly and comparative analysis between the transcriptomes of the two rust species G. yamadae and G. asiaticum. The results identified several orthologous genes, and many expressed genes were identified by annotation. Our analysis of Ka/Ks ratios identified orthologous genes subjected to

  16. Differential Evolution between Monotocous and Polytocous Species

    Directory of Open Access Journals (Sweden)

    Hyeonju Ahn

    2014-04-01

    Full Text Available One of the most important traits for both animal science and livestock production is the number of offspring for a species. This study was performed to identify differentially evolved genes and their distinct functions that influence the number of offspring at birth by comparative analysis of eight monotocous mammals and seven polytocous mammals in a number of scopes: specific amino acid substitution with site-wise adaptive evolution, gene expansion and specific orthologous group. The mutually exclusive amino acid substitution among the 16 mammalian species identified five candidate genes. These genes were both directly and indirectly related to ovulation. Furthermore, in monotocous mammals, the EPH gene family was found to have undergone expansion. Previously, the EPHA4 gene was found to positively affect litter size in pigs and supports the possibility of the EPH gene playing a role in determining the number of offspring per birth. The identified genes in this study offer a basis from which the differences between monotocous and polytocous species can be studied. Furthermore, these genes may harbor some clues to the underlying mechanism, which determines litter size and may prove useful for livestock breeding strategies.

  17. IMGT/GeneInfo: T cell receptor gamma TRG and delta TRD genes in database give access to all TR potential V(D)J recombinations

    Science.gov (United States)

    Baum, Thierry-Pascal; Hierle, Vivien; Pasqual, Nicolas; Bellahcene, Fatena; Chaume, Denys; Lefranc, Marie-Paule; Jouvin-Marche, Evelyne; Marche, Patrice Noël; Demongeot, Jacques

    2006-01-01

    Background Adaptative immune repertoire diversity in vertebrate species is generated by recombination of variable (V), diversity (D) and joining (J) genes in the immunoglobulin (IG) loci of B lymphocytes and in the T cell receptor (TR) loci of T lymphocytes. These V-J and V-D-J gene rearrangements at the DNA level involve recombination signal sequences (RSS). Whereas many data exist, they are scattered in non specialized resources with different nomenclatures (eg. flat files) and are difficult to extract. Description IMGT/GeneInfo is an online information system that provides, through a user-friendly interface, exhaustive information resulting from the complex mechanisms of T cell receptor V-J and V-D-J recombinations. T cells comprise two populations which express the αβ and γδ TR, respectively. The first version of the system dealt with the Homo sapiens and Mus musculus TRA and TRB loci whose gene rearrangements allow the synthesis of the αβ TR chains. In this paper, we present the second version of IMGT/GeneInfo where we complete the database for the Homo sapiens and Mus musculus TRG and TRD loci along with the introduction of a quality control procedure for existing and new data. We also include new functionalities to the four loci analysis, giving, to date, a very informative tool which allows to work on V(D)J genes of all TR loci in both human and mouse species. IMGT/GeneInfo provides more than 59,000 rearrangement combinations with a full gene description which is freely available at . Conclusion IMGT/GeneInfo allows all TR information sequences to be in the same spot, and are now available within two computer-mouse clicks. This is useful for biologists and bioinformaticians for the study of T lymphocyte V(D)J gene rearrangements and their applications in immune response analysis. PMID:16640788

  18. Conservation of the response regulator gene gacA in Pseudomonas species

    NARCIS (Netherlands)

    Souza, J.T.; Mazzola, M.; Raaijmakers, J.M.

    2003-01-01

    The response regulator gene gacA influences the production of several secondary metabolites in both pathogenic and beneficial Pseudomonas spp. In this study, we developed primers and a probe for the gacA gene of Pseudomonas species and sequenced a 425 bp fragment of gacA from ten Pseudomonas strains

  19. Ageing genes

    DEFF Research Database (Denmark)

    Rattan, Suresh

    2018-01-01

    The idea of gerontogenes is in line with the evolutionary explanation of ageing as being an emergent phenomenon as a result of the imperfect maintenance and repair systems. Although evolutionary processes did not select for any specific ageing genes that restrict and determine the lifespan...... of an individual, the term ‘gerontogenes’ primarily refers to any genes that may seem to influence ageing and longevity, without being specifically selected for that role. Such genes can also be called ‘virtual gerontogenes’ by virtue of their indirect influence on the rate and process of ageing. More than 1000...... virtual gerontogenes have been associated with ageing and longevity in model organisms and humans. The ‘real’ genes, which do influence the essential lifespan of a species, and have been selected for in accordance with the evolutionary life history of the species, are known as the longevity assurance...

  20. Genome Wide Identification, Evolutionary, and Expression Analysis of VQ Genes from Two Pyrus Species.

    Science.gov (United States)

    Cao, Yunpeng; Meng, Dandan; Abdullah, Muhammad; Jin, Qing; Lin, Yi; Cai, Yongping

    2018-04-23

    The VQ motif-containing gene, a member of the plant-specific genes, is involved in the plant developmental process and various stress responses. The VQ motif-containing gene family has been studied in several plants, such as rice ( Oryza sativa ), maize ( Zea mays ), and Arabidopsis ( Arabidopsis thaliana ). However, no systematic study has been performed in Pyrus species, which have important economic value. In our study, we identified 41 and 28 VQ motif-containing genes in Pyrus bretschneideri and Pyrus communis , respectively. Phylogenetic trees were calculated using A. thaliana and O. sativa VQ motif-containing genes as a template, allowing us to categorize these genes into nine subfamilies. Thirty-two and eight paralogous of VQ motif-containing genes were found in P. bretschneideri and P. communis , respectively, showing that the VQ motif-containing genes had a more remarkable expansion in P. bretschneideri than in P. communis . A total of 31 orthologous pairs were identified from the P. bretschneideri and P. communis VQ motif-containing genes. Additionally, among the paralogs, we found that these duplication gene pairs probably derived from segmental duplication/whole-genome duplication (WGD) events in the genomes of P. bretschneideri and P. communis , respectively. The gene expression profiles in both P. bretschneideri and P. communis fruits suggested functional redundancy for some orthologous gene pairs derived from a common ancestry, and sub-functionalization or neo-functionalization for some of them. Our study provided the first systematic evolutionary analysis of the VQ motif-containing genes in Pyrus , and highlighted the diversification and duplication of VQ motif-containing genes in both P. bretschneideri and P. communis .

  1. Dissecting specific and global transcriptional regulation of bacterial gene expression

    NARCIS (Netherlands)

    Gerosa, Luca; Kochanowski, Karl; Heinemann, Matthias; Sauer, Uwe

    Gene expression is regulated by specific transcriptional circuits but also by the global expression machinery as a function of growth. Simultaneous specific and global regulation thus constitutes an additional-but often neglected-layer of complexity in gene expression. Here, we develop an

  2. Genome-wide identification and tissue-specific expression analysis of nucleotide binding site-leucine rich repeat gene family in Cicer arietinum (kabuli chickpea).

    Science.gov (United States)

    Sharma, Ranu; Rawat, Vimal; Suresh, C G

    2017-12-01

    The nucleotide binding site-leucine rich repeat (NBS-LRR) proteins play an important role in the defense mechanisms against pathogens. Using bioinformatics approach, we identified and annotated 104 NBS-LRR genes in chickpea. Phylogenetic analysis points to their diversification into two families namely TIR-NBS-LRR and non-TIR-NBS-LRR. Gene architecture revealed intron gain/loss events in this resistance gene family during their independent evolution into two families. Comparative genomics analysis elucidated its evolutionary relationship with other fabaceae species. Around 50% NBS-LRRs reside in macro-syntenic blocks underlining positional conservation along with sequence conservation of NBS-LRR genes in chickpea. Transcriptome sequencing data provided evidence for their transcription and tissue-specific expression. Four cis -regulatory elements namely WBOX, DRE, CBF, and GCC boxes, that commonly occur in resistance genes, were present in the promoter regions of these genes. Further, the findings will provide a strong background to use candidate disease resistance NBS-encoding genes and identify their specific roles in chickpea.

  3. Computational prediction of the Crc regulon identifies genus-wide and species-specific targets of catabolite repression control in Pseudomonas bacteria

    Directory of Open Access Journals (Sweden)

    O'Gara Fergal

    2010-11-01

    Full Text Available Abstract Background Catabolite repression control (CRC is an important global control system in Pseudomonas that fine tunes metabolism in order optimise growth and metabolism in a range of different environments. The mechanism of CRC in Pseudomonas spp. centres on the binding of a protein, Crc, to an A-rich motif on the 5' end of an mRNA resulting in translational down-regulation of target genes. Despite the identification of several Crc targets in Pseudomonas spp. the Crc regulon has remained largely unexplored. Results In order to predict direct targets of Crc, we used a bioinformatics approach based on detection of A-rich motifs near the initiation of translation of all protein-encoding genes in twelve fully sequenced Pseudomonas genomes. As expected, our data predict that genes related to the utilisation of less preferred nutrients, such as some carbohydrates, nitrogen sources and aromatic carbon compounds are targets of Crc. A general trend in this analysis is that the regulation of transporters is conserved across species whereas regulation of specific enzymatic steps or transcriptional activators are often conserved only within a species. Interestingly, some nucleoid associated proteins (NAPs such as HU and IHF are predicted to be regulated by Crc. This finding indicates a possible role of Crc in indirect control over a subset of genes that depend on the DNA bending properties of NAPs for expression or repression. Finally, some virulence traits such as alginate and rhamnolipid production also appear to be regulated by Crc, which links nutritional status cues with the regulation of virulence traits. Conclusions Catabolite repression control regulates a broad spectrum of genes in Pseudomonas. Some targets are genus-wide and are typically related to central metabolism, whereas other targets are species-specific, or even unique to particular strains. Further study of these novel targets will enhance our understanding of how Pseudomonas

  4. Computational prediction of the Crc regulon identifies genus-wide and species-specific targets of catabolite repression control in Pseudomonas bacteria.

    Science.gov (United States)

    Browne, Patrick; Barret, Matthieu; O'Gara, Fergal; Morrissey, John P

    2010-11-25

    Catabolite repression control (CRC) is an important global control system in Pseudomonas that fine tunes metabolism in order optimise growth and metabolism in a range of different environments. The mechanism of CRC in Pseudomonas spp. centres on the binding of a protein, Crc, to an A-rich motif on the 5' end of an mRNA resulting in translational down-regulation of target genes. Despite the identification of several Crc targets in Pseudomonas spp. the Crc regulon has remained largely unexplored. In order to predict direct targets of Crc, we used a bioinformatics approach based on detection of A-rich motifs near the initiation of translation of all protein-encoding genes in twelve fully sequenced Pseudomonas genomes. As expected, our data predict that genes related to the utilisation of less preferred nutrients, such as some carbohydrates, nitrogen sources and aromatic carbon compounds are targets of Crc. A general trend in this analysis is that the regulation of transporters is conserved across species whereas regulation of specific enzymatic steps or transcriptional activators are often conserved only within a species. Interestingly, some nucleoid associated proteins (NAPs) such as HU and IHF are predicted to be regulated by Crc. This finding indicates a possible role of Crc in indirect control over a subset of genes that depend on the DNA bending properties of NAPs for expression or repression. Finally, some virulence traits such as alginate and rhamnolipid production also appear to be regulated by Crc, which links nutritional status cues with the regulation of virulence traits. Catabolite repression control regulates a broad spectrum of genes in Pseudomonas. Some targets are genus-wide and are typically related to central metabolism, whereas other targets are species-specific, or even unique to particular strains. Further study of these novel targets will enhance our understanding of how Pseudomonas bacteria integrate nutritional status cues with the regulation

  5. Computational prediction of the Crc regulon identifies genus-wide and species-specific targets of catabolite repression control in Pseudomonas bacteria

    LENUS (Irish Health Repository)

    Browne, Patrick

    2010-11-25

    Abstract Background Catabolite repression control (CRC) is an important global control system in Pseudomonas that fine tunes metabolism in order optimise growth and metabolism in a range of different environments. The mechanism of CRC in Pseudomonas spp. centres on the binding of a protein, Crc, to an A-rich motif on the 5\\' end of an mRNA resulting in translational down-regulation of target genes. Despite the identification of several Crc targets in Pseudomonas spp. the Crc regulon has remained largely unexplored. Results In order to predict direct targets of Crc, we used a bioinformatics approach based on detection of A-rich motifs near the initiation of translation of all protein-encoding genes in twelve fully sequenced Pseudomonas genomes. As expected, our data predict that genes related to the utilisation of less preferred nutrients, such as some carbohydrates, nitrogen sources and aromatic carbon compounds are targets of Crc. A general trend in this analysis is that the regulation of transporters is conserved across species whereas regulation of specific enzymatic steps or transcriptional activators are often conserved only within a species. Interestingly, some nucleoid associated proteins (NAPs) such as HU and IHF are predicted to be regulated by Crc. This finding indicates a possible role of Crc in indirect control over a subset of genes that depend on the DNA bending properties of NAPs for expression or repression. Finally, some virulence traits such as alginate and rhamnolipid production also appear to be regulated by Crc, which links nutritional status cues with the regulation of virulence traits. Conclusions Catabolite repression control regulates a broad spectrum of genes in Pseudomonas. Some targets are genus-wide and are typically related to central metabolism, whereas other targets are species-specific, or even unique to particular strains. Further study of these novel targets will enhance our understanding of how Pseudomonas bacteria integrate

  6. Species-specific markers for the differential diagnosis of Trypanosoma cruzi and Trypanosoma rangeli and polymorphisms detection in Trypanosoma rangeli.

    Science.gov (United States)

    Ferreira, Keila Adriana Magalhães; Fajardo, Emanuella Francisco; Baptista, Rodrigo P; Macedo, Andrea Mara; Lages-Silva, Eliane; Ramírez, Luis Eduardo; Pedrosa, André Luiz

    2014-06-01

    Trypanosoma cruzi and Trypanosoma rangeli are kinetoplastid parasites which are able to infect humans in Central and South America. Misdiagnosis between these trypanosomes can be avoided by targeting barcoding sequences or genes of each organism. This work aims to analyze the feasibility of using species-specific markers for identification of intraspecific polymorphisms and as target for diagnostic methods by PCR. Accordingly, primers which are able to specifically detect T. cruzi or T. rangeli genomic DNA were characterized. The use of intergenic regions, generally divergent in the trypanosomatids, and the serine carboxypeptidase gene were successful. Using T. rangeli genomic sequences for the identification of group-specific polymorphisms and a polymorphic AT(n) dinucleotide repeat permitted the classification of the strains into two groups, which are entirely coincident with T. rangeli main lineages, KP1 (+) and KP1 (-), previously determined by kinetoplast DNA (kDNA) characterization. The sequences analyzed totalize 622 bp (382 bp represent a hypothetical protein sequence, and 240 bp represent an anonymous sequence), and of these, 581 (93.3%) are conserved sites and 41 bp (6.7%) are polymorphic, with 9 transitions (21.9%), 2 transversions (4.9%), and 30 (73.2%) insertion/deletion events. Taken together, the species-specific markers analyzed may be useful for the development of new strategies for the accurate diagnosis of infections. Furthermore, the identification of T. rangeli polymorphisms has a direct impact in the understanding of the population structure of this parasite.

  7. PHYLOGENETIC RELATIONSHIPS AMONGST 10 Durio SPECIES BASED ON PCR-RFLP ANALYSIS OF TWO CHLOROPLAST GENES

    Directory of Open Access Journals (Sweden)

    Panca J. Santoso

    2013-07-01

    Full Text Available Twenty seven species of Durio have been identified in Sabah and Sarawak, Malaysia, but their relationships have not been studied. This study was conducted to analyse phylogenetic relationships amongst 10 Durio species in Malaysia using PCR-RFLP on two chloroplast DNA genes, i.e. ndhC-trnV and rbcL. DNAs were extracted from young leaves of 11 accessions from 10 Durio species collected from the Tenom Agriculture Research Station, Sabah, and University Agriculture Park, Universiti Putra Malaysia. Two pairs of oligonucleotide primers, N1-N2 and rbcL1-rbcL2, were used to flank the target regions ndhC-trnV and rbcL. Eight restriction enzymes, HindIII, BsuRI, PstI, TaqI, MspI, SmaI, BshNI, and EcoR130I, were used to digest the amplicons. Based on the results of PCR-RFLP on ndhC-trnV gene, the 10 Durio species were grouped into five distinct clusters, and the accessions generally showed high variations. However, based on the results of PCR-RFLP on the rbcL gene, the species were grouped into three distinct clusters, and generally showed low variations. This means that ndhC-trnV gene is more reliable for phylogenetic analysis in lower taxonomic level of Durio species or for diversity analysis, while rbcL gene is reliable marker for phylogenetic analysis at higher taxonomic level. PCR-RFLP on the ndhC-trnV and rbcL genes could therefore be considered as useful markers to phylogenetic analysis amongst Durio species. These finding might be used for further molecular marker assisted in Durio breeding program.

  8. Development of unidentified dna-specific hif 1α gene of lizard (hemidactylus platyurus) which plays a role in tissue regeneration process

    Science.gov (United States)

    Novianti, T.; Sadikin, M.; Widia, S.; Juniantito, V.; Arida, E. A.

    2018-03-01

    Development of unidentified specific gene is essential to analyze the availability these genes in biological process. Identification unidentified specific DNA of HIF 1α genes is important to analyze their contribution in tissue regeneration process in lizard tail (Hemidactylus platyurus). Bioinformatics and PCR techniques are relatively an easier method to identify an unidentified gene. The most widely used method is BLAST (Basic Local Alignment Sequence Tools) method for alignment the sequences from the other organism. BLAST technique is online software from website https://blast.ncbi.nlm.nih.gov/Blast.cgi that capable to generate the similar sequences from closest kinship to distant kindship. Gecko japonicus is a species that it has closest kinship with H. platyurus. Comparing HIF 1 α gene sequence of G. japonicus with the other species used multiple alignment methods from Mega7 software. Conserved base areas were identified using Clustal IX method. Primary DNA of HIF 1 α gene was design by Primer3 software. HIF 1α gene of lizard (H. platyurus) was successfully amplified using a real-time PCR machine by primary DNA that we had designed from Gecko japonicus. Identification unidentified gene of HIF 1a lizard has been done successfully with multiple alignment method. The study was conducted by analyzing during the growth of tail on day 1, 3, 5, 7, 10, 13 and 17 of lizard tail after autotomy. Process amplification of HIF 1α gene was described by CT value in real time PCR machine. HIF 1α expression of gene is quantified by Livak formula. Chi-square statistic test is 0.000 which means that there is a different expression of HIF 1 α gene in every growth day treatment.

  9. Coalescent-based species tree inference from gene tree topologies under incomplete lineage sorting by maximum likelihood.

    Science.gov (United States)

    Wu, Yufeng

    2012-03-01

    Incomplete lineage sorting can cause incongruence between the phylogenetic history of genes (the gene tree) and that of the species (the species tree), which can complicate the inference of phylogenies. In this article, I present a new coalescent-based algorithm for species tree inference with maximum likelihood. I first describe an improved method for computing the probability of a gene tree topology given a species tree, which is much faster than an existing algorithm by Degnan and Salter (2005). Based on this method, I develop a practical algorithm that takes a set of gene tree topologies and infers species trees with maximum likelihood. This algorithm searches for the best species tree by starting from initial species trees and performing heuristic search to obtain better trees with higher likelihood. This algorithm, called STELLS (which stands for Species Tree InfErence with Likelihood for Lineage Sorting), has been implemented in a program that is downloadable from the author's web page. The simulation results show that the STELLS algorithm is more accurate than an existing maximum likelihood method for many datasets, especially when there is noise in gene trees. I also show that the STELLS algorithm is efficient and can be applied to real biological datasets. © 2011 The Author. Evolution© 2011 The Society for the Study of Evolution.

  10. Trans-specific gene silencing of acetyl-CoA carboxylase in a root-parasitic plant.

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    Bandaranayake, Pradeepa C G; Yoder, John I

    2013-05-01

    Parasitic species of the family Orobanchaceae are devastating agricultural pests in many parts of the world. The control of weedy Orobanchaceae spp. is challenging, particularly due to the highly coordinated life cycles of the parasite and host plants. Although host genetic resistance often provides the foundation of plant pathogen management, few genes that confer resistance to root parasites have been identified and incorporated into crop species. Members of the family Orobanchaceae acquire water, nutrients, macromolecules, and oligonucleotides from host plants through haustoria that connect parasite and host plant roots. We are evaluating a resistance strategy based on using interfering RNA (RNAi) that is made in the host but inhibitory in the parasite as a parasite-derived oligonucleotide toxin. Sequences from the cytosolic acetyl-CoA carboxylase (ACCase) gene from Triphysaria versicolor were cloned in hairpin conformation and introduced into Medicago truncatula roots by Agrobacterium rhizogenes transformation. Transgenic roots were recovered for four of five ACCase constructions and infected with T. versicolor against parasitic weeds. In all cases, Triphysaria root viability was reduced up to 80% when parasitizing a host root bearing the hairpin ACCase. Triphysaria root growth was recovered by exogenous application of malonate. Reverse-transcriptase polymerase chain reaction (RT-PCR) showed that ACCase transcript levels were dramatically decreased in Triphysaria spp. parasitizing transgenic Medicago roots. Northern blot analysis identified a 21-nucleotide, ACCase-specific RNA in transgenic M. truncatula and in T. versicolor attached to them. One hairpin ACCase construction was lethal to Medicago spp. unless grown in media supplemented with malonate. Quantitative RT-PCR showed that the Medicago ACCase was inhibited by the Triphysaria ACCase RNAi. This work shows that ACCase is an effective target for inactivation in parasitic plants by trans-specific gene

  11. Death and resurrection of the human IRGM gene.

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    Cemalettin Bekpen

    2009-03-01

    Full Text Available Immunity-related GTPases (IRG play an important role in defense against intracellular pathogens. One member of this gene family in humans, IRGM, has been recently implicated as a risk factor for Crohn's disease. We analyzed the detailed structure of this gene family among primates and showed that most of the IRG gene cluster was deleted early in primate evolution, after the divergence of the anthropoids from prosimians ( about 50 million years ago. Comparative sequence analysis of New World and Old World monkey species shows that the single-copy IRGM gene became pseudogenized as a result of an Alu retrotransposition event in the anthropoid common ancestor that disrupted the open reading frame (ORF. We find that the ORF was reestablished as a part of a polymorphic stop codon in the common ancestor of humans and great apes. Expression analysis suggests that this change occurred in conjunction with the insertion of an endogenous retrovirus, which altered the transcription initiation, splicing, and expression profile of IRGM. These data argue that the gene became pseudogenized and was then resurrected through a series of complex structural events and suggest remarkable functional plasticity where alleles experience diverse evolutionary pressures over time. Such dynamism in structure and evolution may be critical for a gene family locked in an arms race with an ever-changing repertoire of intracellular parasites.

  12. Rhizome of life, catastrophes, sequence exchanges, gene creations and giant viruses: How microbial genomics challenges Darwin

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    Vicky eMerhej

    2012-08-01

    Full Text Available Darwin’s theory about the evolution of species has been the object of considerable dispute. In this review, we have described seven key principles in Darwin’s book The Origin of Species and tried to present how genomics challenge each of these concepts and improve our knowledge about evolution. Darwin believed that species evolution consists on a positive directional selection ensuring the survival of the fittest. The most developed state of the species is characterized by increasing complexity. Darwin proposed the theory of descent with modification according to which all species evolve from a single common ancestor through a gradual process of small modification of their vertical inheritance. Finally, the process of evolution can be depicted in the form of a tree. However, microbial genomics showed that evolution is better described as the biological changes over time." The mode of change is not unidirectional and does not necessarily favors advantageous mutations to increase fitness it is rather subject to random selection as a result of catastrophic stochastic processes. Complexity is not necessarily the completion of development: several complex organisms have gone extinct and many microbes including bacteria with intracellular lifestyle have streamlined highly effective genomes. Genomes evolve through large events of gene deletions, duplications, insertions and genomes rearrangements rather than a gradual adaptative process. Genomes are dynamic and chimeric entities with gene repertoires that result from vertical and horizontal acquisitions as well as de novo gene creation. The chimeric character of microbial genomes excludes the possibility of finding a single common ancestor for all the genes recorded currently. Genomes are collections of genes with different evolutionary histories that cannot be represented by a single tree of life. A forest, a network or a rhizome of life may be more accurate to represent evolutionary relationships

  13. Climate-Driven Reshuffling of Species and Genes: Potential Conservation Roles for Species Translocations and Recombinant Hybrid Genotypes.

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    Scriber, Jon Mark

    2013-12-24

    Comprising 50%-75% of the world's fauna, insects are a prominent part of biodiversity in communities and ecosystems globally. Biodiversity across all levels of biological classifications is fundamentally based on genetic diversity. However, the integration of genomics and phylogenetics into conservation management may not be as rapid as climate change. The genetics of hybrid introgression as a source of novel variation for ecological divergence and evolutionary speciation (and resilience) may generate adaptive potential and diversity fast enough to respond to locally-altered environmental conditions. Major plant and herbivore hybrid zones with associated communities deserve conservation consideration. This review addresses functional genetics across multi-trophic-level interactions including "invasive species" in various ecosystems as they may become disrupted in different ways by rapid climate change. "Invasive genes" (into new species and populations) need to be recognized for their positive creative potential and addressed in conservation programs. "Genetic rescue" via hybrid translocations may provide needed adaptive flexibility for rapid adaptation to environmental change. While concerns persist for some conservationists, this review emphasizes the positive aspects of hybrids and hybridization. Specific implications of natural genetic introgression are addressed with a few examples from butterflies, including transgressive phenotypes and climate-driven homoploid recombinant hybrid speciation. Some specific examples illustrate these points using the swallowtail butterflies (Papilionidae) with their long-term historical data base (phylogeographical diversity changes) and recent (3-decade) climate-driven temporal and genetic divergence in recombinant homoploid hybrids and relatively recent hybrid speciation of Papilio appalachiensis in North America. Climate-induced "reshuffling" (recombinations) of species composition, genotypes, and genomes may become

  14. Structural and functional diversification in the teleost S100 family of calcium-binding proteins

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    Korsching Sigrun I

    2008-02-01

    Full Text Available Abstract Background Among the EF-Hand calcium-binding proteins the subgroup of S100 proteins constitute a large family with numerous and diverse functions in calcium-mediated signaling. The evolutionary origin of this family is still uncertain and most studies have examined mammalian family members. Results We have performed an extensive search in several teleost genomes to establish the s100 gene family in fish. We report that the teleost S100 repertoire comprises fourteen different subfamilies which show remarkable similarity across six divergent teleost species. Individual species feature distinctive subsets of thirteen to fourteen genes that result from local gene duplications and gene losses. Eight of the fourteen S100 subfamilies are unique for teleosts, while six are shared with mammalian species and three of those even with cartilaginous fish. Several S100 family members are found in jawless fish already, but none of them are clear orthologs of cartilaginous or bony fish s100 genes. All teleost s100 genes show the expected structural features and are subject to strong negative selection. Many aspects of the genomic arrangement and location of mammalian s100 genes are retained in the teleost s100 gene family, including a completely conserved intron/exon border between the two EF hands. Zebrafish s100 genes exhibit highly specific and characteristic expression patterns, showing both redundancy and divergence in their cellular expression. In larval tissue expression is often restricted to specific cell types like keratinocytes, hair cells, ionocytes and olfactory receptor neurons as demonstrated by in situ hybridization. Conclusion The origin of the S100 family predates at least the segregation of jawed from jawless fish and some extant family members predate the divergence of bony from cartilaginous fish. Despite a complex pattern of gene gains and losses the total repertoire size is remarkably constant between species. On the expression

  15. Genomics of a Metamorphic Timing QTL: met1 Maps to a Unique Genomic Position and Regulates Morph and Species-Specific Patterns of Brain Transcription

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    Page, Robert B.; Boley, Meredith A.; Kump, David K.; Voss, Stephen R.

    2013-01-01

    Very little is known about genetic factors that regulate life history transitions during ontogeny. Closely related tiger salamanders (Ambystoma species complex) show extreme variation in metamorphic timing, with some species foregoing metamorphosis altogether, an adaptive trait called paedomorphosis. Previous studies identified a major effect quantitative trait locus (met1) for metamorphic timing and expression of paedomorphosis in hybrid crosses between the biphasic Eastern tiger salamander (Ambystoma tigrinum tigrinum) and the paedomorphic Mexican axolotl (Ambystoma mexicanum). We used existing hybrid mapping panels and a newly created hybrid cross to map the met1 genomic region and determine the effect of met1 on larval growth, metamorphic timing, and gene expression in the brain. We show that met1 maps to the position of a urodele-specific chromosome rearrangement on linkage group 2 that uniquely brought functionally associated genes into linkage. Furthermore, we found that more than 200 genes were differentially expressed during larval development as a function of met1 genotype. This list of differentially expressed genes is enriched for proteins that function in the mitochondria, providing evidence of a link between met1, thyroid hormone signaling, and mitochondrial energetics associated with metamorphosis. Finally, we found that met1 significantly affected metamorphic timing in hybrids, but not early larval growth rate. Collectively, our results show that met1 regulates species and morph-specific patterns of brain transcription and life history variation. PMID:23946331

  16. Annotation of a hybrid partial genome of the Coffee Rust (Hemileia vastatrix contributes to the gene repertoire catalogue of the Pucciniales

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    Marco Aurelio Cristancho

    2014-10-01

    Full Text Available Coffee leaf rust caused by the fungus Hemileia vastatrix is the most damaging disease to coffee worldwide. The pathogen has recently appeared in multiple outbreaks in coffee producing countries resulting in significant yield losses and increases in costs related to its control. New races/isolates are constantly emerging as evidenced by the presence of the fungus in plants that were previously resistant. Genomic studies are opening new avenues for the study of the evolution of pathogens, the detailed description of plant-pathogen interactions and the development of molecular techniques for the identification of individual isolates. For this purpose we sequenced 8 different H. vastatrix isolates using NGS technologies and gathered partial genome assemblies due to the large repetitive content in the coffee rust hybrid genome; 74.4% of the assembled contigs harbor repetitive sequences. A hybrid assembly of 333Mb was built based on the 8 isolates; this assembly was used for subsequent analyses.Analysis of the conserved gene space showed that the hybrid H. vastatrix genome, though highly fragmented, had a satisfactory level of completion with 91.94% of core protein-coding orthologous genes present. RNA-Seq from urediniospores was used to guide the de novo annotation of the H. vastatrix gene complement. In total, 14,445 genes organized in 3,921 families were uncovered; a considerable proportion of the predicted proteins (73.8% were homologous to other Pucciniales species genomes. Several gene families related to the fungal lifestyle were identified, particularly 483 predicted secreted proteins that represent candidate effector genes and will provide interesting hints to decipher virulence in the coffee rust fungus. The genome sequence of Hva will serve as a template to understand the molecular mechanisms used by this fungus to attack the coffee plant, to study the diversity of this species and for the development of molecular markers to distinguish

  17. Microarray meta-analysis to explore abiotic stress-specific gene expression patterns in Arabidopsis.

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    Shen, Po-Chih; Hour, Ai-Ling; Liu, Li-Yu Daisy

    2017-12-01

    Abiotic stresses are the major limiting factors that affect plant growth, development, yield and final quality. Deciphering the underlying mechanisms of plants' adaptations to stresses using few datasets might overlook the different aspects of stress tolerance in plants, which might be simultaneously and consequently operated in the system. Fortunately, the accumulated microarray expression data offer an opportunity to infer abiotic stress-specific gene expression patterns through meta-analysis. In this study, we propose to combine microarray gene expression data under control, cold, drought, heat, and salt conditions and determined modules (gene sets) of genes highly associated with each other according to the observed expression data. By analyzing the expression variations of the Eigen genes from different conditions, we had identified two, three, and five gene modules as cold-, heat-, and salt-specific modules, respectively. Most of the cold- or heat-specific modules were differentially expressed to a particular degree in shoot samples, while most of the salt-specific modules were differentially expressed to a particular degree in root samples. A gene ontology (GO) analysis on the stress-specific modules suggested that the gene modules exclusively enriched stress-related GO terms and that different genes under the same GO terms may be alternatively disturbed in different conditions. The gene regulatory events for two genes, DREB1A and DEAR1, in the cold-specific gene module had also been validated, as evidenced through the literature search. Our protocols study the specificity of the gene modules that were specifically activated under a particular type of abiotic stress. The biplot can also assist to visualize the stress-specific gene modules. In conclusion, our approach has the potential to further elucidate mechanisms in plants and beneficial for future experiments design under different abiotic stresses.

  18. Identifying knowledge gaps for gene drive research to control invasive animal species: The next CRISPR step

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    Dorian Moro

    2018-01-01

    Full Text Available Invasive animals have been linked to the extinctions of native wildlife, and to significant agricultural financial losses or impacts. Current approaches to control invasive species require ongoing resources and management over large geographic scales, and often result in the short-term suppression of populations. New and innovative approaches are warranted. Recently, the RNA guided gene drive system based on CRISPR/Cas9 is being proposed as a potential gene editing tool that could be used by wildlife managers as a non-lethal addition or alternative to help reduce pest animal populations. While regulatory control and social acceptance are crucial issues that must be addressed, there is an opportunity now to identify the knowledge and research gaps that exist for some important invasive species. Here we systematically determine the knowledge gaps for pest species for which gene drives could potentially be applied. We apply a conceptual ecological risk framework within the gene drive context within an Australian environment to identify key requirements for undertaking work on seven exemplar invasive species in Australia. This framework allows an evaluation of the potential research on an invasive species of interest and within a gene drive and risk context. We consider the currently available biological, genetic and ecological information for the house mouse, European red fox, feral cat, European rabbit, cane toad, black rat and European starling to evaluate knowledge gaps and identify candidate species for future research. We discuss these findings in the context of future thematic areas of research worth pursuing in preparation for a more formal assessment of the use of gene drives as a novel strategy for the control of these and other invasive species. Keywords: Invasive species, Gene drive, CRISPR, Pest management, Islands

  19. Genome-Wide Distribution, Organisation and Functional Characterization of Disease Resistance and Defence Response Genes across Rice Species

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    Singh, Sangeeta; Chand, Suresh; Singh, N. K.; Sharma, Tilak Raj

    2015-01-01

    The resistance (R) genes and defense response (DR) genes have become very important resources for the development of disease resistant cultivars. In the present investigation, genome-wide identification, expression, phylogenetic and synteny analysis was done for R and DR-genes across three species of rice viz: Oryza sativa ssp indica cv 93-11, Oryza sativa ssp japonica and wild rice species, Oryza brachyantha. We used the in silico approach to identify and map 786 R -genes and 167 DR-genes, 672 R-genes and 142 DR-genes, 251 R-genes and 86 DR-genes in the japonica, indica and O. brachyanth a genomes, respectively. Our analysis showed that 60.5% and 55.6% of the R-genes are tandemly repeated within clusters and distributed over all the rice chromosomes in indica and japonica genomes, respectively. The phylogenetic analysis along with motif distribution shows high degree of conservation of R- and DR-genes in clusters. In silico expression analysis of R-genes and DR-genes showed more than 85% were expressed genes showing corresponding EST matches in the databases. This study gave special emphasis on mechanisms of gene evolution and duplication for R and DR genes across species. Analysis of paralogs across rice species indicated 17% and 4.38% R-genes, 29% and 11.63% DR-genes duplication in indica and Oryza brachyantha, as compared to 20% and 26% duplication of R-genes and DR-genes in japonica respectively. We found that during the course of duplication only 9.5% of R- and DR-genes changed their function and rest of the genes have maintained their identity. Syntenic relationship across three genomes inferred that more orthology is shared between indica and japonica genomes as compared to brachyantha genome. Genome wide identification of R-genes and DR-genes in the rice genome will help in allele mining and functional validation of these genes, and to understand molecular mechanism of disease resistance and their evolution in rice and related species. PMID:25902056

  20. Genomic evidence of bitter taste in snakes and phylogenetic analysis of bitter taste receptor genes in reptiles

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    Huaming Zhong

    2017-08-01

    Full Text Available As nontraditional model organisms with extreme physiological and morphological phenotypes, snakes are believed to possess an inferior taste system. However, the bitter taste sensation is essential to distinguish the nutritious and poisonous food resources and the genomic evidence of bitter taste in snakes is largely scarce. To explore the genetic basis of the bitter taste of snakes and characterize the evolution of bitter taste receptor genes (Tas2rs in reptiles, we identified Tas2r genes in 19 genomes (species corresponding to three orders of non-avian reptiles. Our results indicated contractions of Tas2r gene repertoires in snakes, however dramatic gene expansions have occurred in lizards. Phylogenetic analysis of the Tas2rs with NJ and BI methods revealed that Tas2r genes of snake species formed two clades, whereas in lizards the Tas2r genes clustered into two monophyletic clades and four large clades. Evolutionary changes (birth and death of intact Tas2r genes in reptiles were determined by reconciliation analysis. Additionally, the taste signaling pathway calcium homeostasis modulator 1 (Calhm1 gene of snakes was putatively functional, suggesting that snakes still possess bitter taste sensation. Furthermore, Phylogenetically Independent Contrasts (PIC analyses reviewed a significant correlation between the number of Tas2r genes and the amount of potential toxins in reptilian diets, suggesting that insectivores such as some lizards may require more Tas2rs genes than omnivorous and carnivorous reptiles.

  1. High-throughput analysis of candidate imprinted genes and allele-specific gene expression in the human term placenta

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    Clark Taane G

    2010-04-01

    Full Text Available Abstract Background Imprinted genes show expression from one parental allele only and are important for development and behaviour. This extreme mode of allelic imbalance has been described for approximately 56 human genes. Imprinting status is often disrupted in cancer and dysmorphic syndromes. More subtle variation of gene expression, that is not parent-of-origin specific, termed 'allele-specific gene expression' (ASE is more common and may give rise to milder phenotypic differences. Using two allele-specific high-throughput technologies alongside bioinformatics predictions, normal term human placenta was screened to find new imprinted genes and to ascertain the extent of ASE in this tissue. Results Twenty-three family trios of placental cDNA, placental genomic DNA (gDNA and gDNA from both parents were tested for 130 candidate genes with the Sequenom MassArray system. Six genes were found differentially expressed but none imprinted. The Illumina ASE BeadArray platform was then used to test 1536 SNPs in 932 genes. The array was enriched for the human orthologues of 124 mouse candidate genes from bioinformatics predictions and 10 human candidate imprinted genes from EST database mining. After quality control pruning, a total of 261 informative SNPs (214 genes remained for analysis. Imprinting with maternal expression was demonstrated for the lymphocyte imprinted gene ZNF331 in human placenta. Two potential differentially methylated regions (DMRs were found in the vicinity of ZNF331. None of the bioinformatically predicted candidates tested showed imprinting except for a skewed allelic expression in a parent-specific manner observed for PHACTR2, a neighbour of the imprinted PLAGL1 gene. ASE was detected for two or more individuals in 39 candidate genes (18%. Conclusions Both Sequenom and Illumina assays were sensitive enough to study imprinting and strong allelic bias. Previous bioinformatics approaches were not predictive of new imprinted genes

  2. Gene duplication, tissue-specific gene expression and sexual conflict in stalk-eyed flies (Diopsidae).

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    Baker, Richard H; Narechania, Apurva; Johns, Philip M; Wilkinson, Gerald S

    2012-08-19

    Gene duplication provides an essential source of novel genetic material to facilitate rapid morphological evolution. Traits involved in reproduction and sexual dimorphism represent some of the fastest evolving traits in nature, and gene duplication is intricately involved in the origin and evolution of these traits. Here, we review genomic research on stalk-eyed flies (Diopsidae) that has been used to examine the extent of gene duplication and its role in the genetic architecture of sexual dimorphism. Stalk-eyed flies are remarkable because of the elongation of the head into long stalks, with the eyes and antenna laterally displaced at the ends of these stalks. Many species are strongly sexually dimorphic for eyespan, and these flies have become a model system for studying sexual selection. Using both expressed sequence tag and next-generation sequencing, we have established an extensive database of gene expression in the developing eye-antennal imaginal disc, the adult head and testes. Duplicated genes exhibit narrower expression patterns than non-duplicated genes, and the testes, in particular, provide an abundant source of gene duplication. Within somatic tissue, duplicated genes are more likely to be differentially expressed between the sexes, suggesting gene duplication may provide a mechanism for resolving sexual conflict.

  3. Species-specific nested PCR as a diagnostic tool for Brucella ovis infection in rams

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    L.F. Costa

    2013-02-01

    Full Text Available The aim of the present study was to evaluate a species-specific nested PCR based on a previously described species-specific PCR for detection of B. ovis in semen and urine samples of experimentally infected rams. The performance of the species-specific nested PCR was compared with the results of a genus-specific PCR. Fourteen rams were experimentally infected with the Brucella ovis REO 198 strain and samples of semen and urine were collected every week up to 180 days post infection. Out of 83 semen samples collected, 42 (50.6% were positive for the species-specific nested PCR, and 23 (27.7% were positive for the genus-specific PCR. Out of 75 urine samples, 49 (65.3% were positive for the species-specific nested PCR, whereas 11 (14.6% were genus-specific PCR positive. Species-specific nested PCR was significantly more sensitive (P<0.001 than the genus-specific PCR in semen and urine from experimentally infected rams. In conclusion, the species-specific nested PCR developed in this study may be used as a diagnostic tool for the detection of B. ovis in semen and urine samples from suspected rams.

  4. Species boundaries of Gulf of Mexico vestimentiferans (Polychaeta, Siboglinidae) inferred from mitochondrial genes

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    Pia Miglietta, Maria; Hourdez, Stephane; Cowart, Dominique A.; Schaeffer, Stephen W.; Fisher, Charles

    2010-11-01

    At least six morphospecies of vestimentiferan tubeworms are associated with cold seeps in the Gulf of Mexico (GOM). The physiology and ecology of the two best-studied species from depths above 1000 m in the upper Louisiana slope (Lamellibrachia luymesi and Seepiophila jonesi) are relatively well understood. The biology of one rare species from the upper slope (escarpiid sp. nov.) and three morphospecies found at greater depths in the GOM (Lamellibrachia sp. 1, L. sp. 2, and Escarpia laminata) are not as well understood. Here we address species distributions and boundaries of cold-seep tubeworms using phylogenetic hypotheses based on two mitochondrial genes. Fragments of the mitochondrial large ribosomal subunit rDNA (16S) and cytochrome oxidase subunit I (COI) genes were sequenced for 167 vestimentiferans collected from the GOM and analyzed in the context of other seep vestimentiferans for which sequence data were available. The analysis supported five monophyletic clades of vestimentiferans in the GOM. Intra-clade variation in both genes was very low, and there was no apparent correlation between the within-clade diversity and collection depth or location. Two of the morphospecies of Lamellibrachia from different depths in the GOM could not be distinguished by either mitochondrial gene. Similarly, E. laminata could not be distinguished from other described species of Escarpia from either the west coast of Africa or the eastern Pacific using COI. We suggest that the mitochondrial COI and 16S genes have little utility as barcoding markers for seep vestimentiferan tubeworms.

  5. High-Resolution Melting Curve Analysis of the 16S Ribosomal Gene to Detect and Identify Pathogenic and Saprophytic Leptospira Species in Colombian Isolates.

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    Peláez Sánchez, Ronald G; Quintero, Juan Álvaro López; Pereira, Martha María; Agudelo-Flórez, Piedad

    2017-05-01

    AbstractIt is important to identify the circulating Leptospira agent to enhance the performance of serodiagnostic tests by incorporating specific antigens of native species, develop vaccines that take into account the species/serovars circulating in different regions, and optimize prevention and control strategies. The objectives of this study were to develop a polymerase chain reaction (PCR)-high-resolution melting (HRM) assay for differentiating between species of the genus Leptospira and to verify its usefulness in identifying unknown samples to species level. A set of primers from the initial region of the 16S ribosomal gene was designed to detect and differentiate the 22 species of Leptospira . Eleven reference strains were used as controls to establish the reference species and differential melting curves. Twenty-five Colombian Leptospira isolates were studied to evaluate the usefulness of the PCR-HRM assay in identifying unknown samples to species level. This identification was confirmed by sequencing and phylogenetic analysis of the 16S ribosomal gene. Eleven Leptospira species were successfully identified, except for Leptospira meyeri / Leptospira yanagawae because the sequences were 100% identical. The 25 isolates from humans, animals, and environmental water sources were identified as Leptospira santarosai (twelve), Leptospira interrogans (nine), and L. meyeri / L. yanagawae (four). The species verification was 100% concordant between PCR-HRM and phylogenetic analysis of the 16S ribosomal gene. The PCR-HRM assay designed in this study is a useful tool for identifying Leptospira species from isolates.

  6. Rapid identification of probiotic Lactobacillus species by multiplex PCR using species-specific primers based on the region extending from 16S rRNA through 23S rRNA.

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    Kwon, Hyuk-Sang; Yang, Eun-Hee; Yeon, Seung-Woo; Kang, Byoung-Hwa; Kim, Tae-Yong

    2004-10-15

    This study aimed to develop a novel multiplex polymerase chain reaction (PCR) primer set for the identification of seven probiotic Lactobacillus species such as Lactobacillus acidophilus, Lactobacillus delbrueckii, Lactobacillus casei, Lactobacillus gasseri, Lactobacillus plantarum, Lactobacillus reuteri and Lactobacillus rhamnosus. The primer set, comprising of seven specific and two conserved primers, was derived from the integrated sequences of 16S and 23S rRNA genes and their rRNA intergenic spacer region of each species. It was able to identify the seven target species with 93.6% accuracy, which exceeds that of the general biochemical methods. The phylogenetic analyses, using 16S rDNA sequences of the probiotic isolates, also provided further support that the results from the multiplex PCR assay were trustworthy. Taken together, we suggest that the multiplex primer set is an efficient tool for simple, rapid and reliable identification of seven Lactobacillus species.

  7. Genomic and expression analyses of Tursiops truncatus T cell receptor gamma (TRG) and alpha/delta (TRA/TRD) loci reveal a similar basic public γδ repertoire in dolphin and human.

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    Linguiti, Giovanna; Antonacci, Rachele; Tasco, Gianluca; Grande, Francesco; Casadio, Rita; Massari, Serafina; Castelli, Vito; Consiglio, Arianna; Lefranc, Marie-Paule; Ciccarese, Salvatrice

    2016-08-15

    The bottlenose dolphin (Tursiops truncatus) is a mammal that belongs to the Cetartiodactyla and have lived in marine ecosystems for nearly 60 millions years. Despite its popularity, our knowledge about its adaptive immunity and evolution is very limited. Furthermore, nothing is known about the genomics and evolution of dolphin antigen receptor immunity. Here we report a evolutionary and expression study of Tursiops truncatus T cell receptor gamma (TRG) and alpha/delta (TRA/TRD) genes. We have identified in silico the TRG and TRA/TRD genes and analyzed the relevant mature transcripts in blood and in skin from four subjects. The dolphin TRG locus is the smallest and simplest of all mammalian loci as yet studied. It shows a genomic organization comprising two variable (V1 and V2), three joining (J1, J2 and J3) and a single constant (C), genes. Despite the fragmented nature of the genome assemblies, we deduced the TRA/TRD locus organization, with the recent TRDV1 subgroup genes duplications, as it is expected in artiodactyls. Expression analysis from blood of a subject allowed us to assign unambiguously eight TRAV genes to those annotated in the genomic sequence and to twelve new genes, belonging to five different subgroups. All transcripts were productive and no relevant biases towards TRAV-J rearrangements are observed. Blood and skin from four unrelated subjects expression data provide evidence for an unusual ratio of productive/unproductive transcripts which arise from the TRG V-J gene rearrangement and for a "public" gamma delta TR repertoire. The productive cDNA sequences, shared both in the same and in different individuals, include biases of the TRGV1 and TRGJ2 genes. The high frequency of TRGV1-J2/TRDV1- D1-J4 productive rearrangements in dolphins may represent an interesting oligo-clonal population comparable to that found in human with the TRGV9- JP/TRDV2-D-J T cells and in primates. Although the features of the TRG and TRA/TRD loci organization reflect

  8. New frontier in regenerative medicine: site-specific gene correction in patient-specific induced pluripotent stem cells.

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    Garate, Zita; Davis, Brian R; Quintana-Bustamante, Oscar; Segovia, Jose C

    2013-06-01

    Advances in cell and gene therapy are opening up new avenues for regenerative medicine. Because of their acquired pluripotency, human induced pluripotent stem cells (hiPSCs) are a promising source of autologous cells for regenerative medicine. They show unlimited self-renewal while retaining the ability, in principle, to differentiate into any cell type of the human body. Since Yamanaka and colleagues first reported the generation of hiPSCs in 2007, significant efforts have been made to understand the reprogramming process and to generate hiPSCs with potential for clinical use. On the other hand, the development of gene-editing platforms to increase homologous recombination efficiency, namely DNA nucleases (zinc finger nucleases, TAL effector nucleases, and meganucleases), is making the application of locus-specific gene therapy in human cells an achievable goal. The generation of patient-specific hiPSC, together with gene correction by homologous recombination, will potentially allow for their clinical application in the near future. In fact, reports have shown targeted gene correction through DNA-Nucleases in patient-specific hiPSCs. Various technologies have been described to reprogram patient cells and to correct these patient hiPSCs. However, no approach has been clearly more efficient and safer than the others. In addition, there are still significant challenges for the clinical application of these technologies, such as inefficient differentiation protocols, genetic instability resulting from the reprogramming process and hiPSC culture itself, the efficacy and specificity of the engineered DNA nucleases, and the overall homologous recombination efficiency. To summarize advances in the generation of gene corrected patient-specific hiPSCs, this review focuses on the available technological platforms, including their strengths and limitations regarding future therapeutic use of gene-corrected hiPSCs.

  9. Elucidating Microbial Species-Specific Effects on Organic Matter Transformation in Marine Sediments

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    Mahmoudi, N.; Enke, T. N.; Beaupre, S. R.; Teske, A.; Cordero, O. X.; Pearson, A.

    2017-12-01

    Microbial transformation and decomposition of organic matter in sediments constitutes one of the largest fluxes of carbon in marine environments. Mineralization of sedimentary organic matter by microorganisms results in selective degradation such that bioavailable or accessible compounds are rapidly metabolized while more recalcitrant, complex compounds are preserved and buried in sediment. Recent studies have found that the ability to use different carbon sources appears to vary among microorganisms, suggesting that the availability of certain pools of carbon can be specific to the taxa that utilize the pool. This implies that organic matter mineralization in marine environments may depend on the metabolic potential of the microbial populations that are present and active. The goal of our study was to investigate the extent to which organic matter availability and transformation may be species-specific using sediment from Guaymas Basin (Gulf of California). We carried out time-series incubations using bacterial isolates and sterilized sediment in the IsoCaRB system which allowed us to measure the production rates and natural isotopic signatures (δ13C and Δ14C) of microbially-respired CO2. Separate incubations using two different marine bacterial isolates (Vibrio sp. and Pseudoalteromonas sp.) and sterilized Guaymas Basin sediment under oxic conditions showed that the rate and total quantity of organic matter metabolized by these two species differs. Approximately twice as much CO2 was collected during the Vibrio sp. incubation compared to the Pseudoalteromonas sp. incubation. Moreover, the rate at which organic matter was metabolized by the Vibrio sp. was much higher than the Pseudoalteromonas sp. indicating the intrinsic availability of organic matter in sediments may depend on the species that is present and active. Isotopic analyses of microbially respired CO2 will be used to constrain the type and age of organic matter that is accessible to each species

  10. Genes Suggest Ancestral Colour Polymorphisms Are Shared across Morphologically Cryptic Species in Arctic Bumblebees.

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    Paul H Williams

    Full Text Available Our grasp of biodiversity is fine-tuned through the process of revisionary taxonomy. If species do exist in nature and can be discovered with available techniques, then we expect these revisions to converge on broadly shared interpretations of species. But for the primarily arctic bumblebees of the subgenus Alpinobombus of the genus Bombus, revisions by some of the most experienced specialists are unusual for bumblebees in that they have all reached different conclusions on the number of species present. Recent revisions based on skeletal morphology have concluded that there are from four to six species, while variation in colour pattern of the hair raised questions as to whether at least seven species might be present. Even more species are supported if we accept the recent move away from viewing species as morphotypes to viewing them instead as evolutionarily independent lineages (EILs using data from genes. EILs are recognised here in practice from the gene coalescents that provide direct evidence for their evolutionary independence. We show from fitting both general mixed Yule/coalescent (GMYC models and Poisson-tree-process (PTP models to data for the mitochondrial COI gene that there is support for nine species in the subgenus Alpinobombus. Examination of the more slowly evolving nuclear PEPCK gene shows further support for a previously unrecognised taxon as a new species in northwestern North America. The three pairs of the most morphologically similar sister species are separated allopatrically and prevented from interbreeding by oceans. We also find that most of the species show multiple shared colour patterns, giving the appearance of mimicry among parts of the different species. However, reconstructing ancestral colour-pattern states shows that speciation is likely to have cut across widespread ancestral polymorphisms, without or largely without convergence. In the particular case of Alpinobombus, morphological, colour-pattern, and

  11. The evolution and expression of panarthropod frizzled genes

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    Ralf eJanssen

    2015-08-01

    Full Text Available Wnt signaling regulates many important processes during metazoan development. It has been shown that Wnt ligands represent an ancient and diverse family of proteins that likely function in complex signaling landscapes to induce target cells via receptors including those of the Frizzled (Fz family. The four subfamilies of Fz receptors also evolved early in metazoan evolution. To date, Fz receptors have been characterised mainly in mammals, the nematode Caenorhabditis elegans and insects such as Drosophila melanogaster. To compare these findings with other metazoans, we explored the repertoire of fz genes in three panarthropod species: Parasteatoda tepidariorum, Glomeris marginata and Euperipatoides kanangrensis, representing the Chelicerata, Myriapoda and Onychophora respectively. We found that these three diverse panarthropods each have four fz genes, with representatives of all four metazoan fz subfamilies found in Glomeris and Euperipatoides, while Parasteatoda does not have a fz3 gene, but has two fz4 paralogues. Furthermore we characterized the expression patterns of all the fz genes among these animals. Our results exemplify the evolutionary diversity of Fz receptors and reveals conserved and divergent aspects of their protein sequences and expression patterns among panarthropods; thus providing new insights into the evolution of Wnt signaling more generally.

  12. Phylogeographical patterns among Mediterranean sepiolid squids and their Vibrio symbionts: environment drives specificity among sympatric species.

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    Zamborsky, D J; Nishiguchi, M K

    2011-01-01

    Bobtail squid from the genera Sepiola and Rondeletiola (Cephalopoda: Sepiolidae) form mutualistic associations with luminous Gram-negative bacteria (Gammaproteobacteria: Vibrionaceae) from the genera Vibrio and Photobacterium. Symbiotic bacteria proliferate inside a bilobed light organ until they are actively expelled by the host into the surrounding environment on a diel basis. This event results in a dynamic symbiont population with the potential to establish the symbiosis with newly hatched sterile (axenic) juvenile sepiolids. In this study, we examined the genetic diversity found in populations of sympatric sepiolid squid species and their symbionts by the use of nested clade analysis with multiple gene analyses. Variation found in the distribution of different species of symbiotic bacteria suggests a strong influence of abiotic factors in the local environment, affecting bacterial distribution among sympatric populations of hosts. These abiotic factors include temperature differences incurred by a shallow thermocline, as well as a lack of strong coastal water movement accompanied by seasonal temperature changes in overlapping niches. Host populations are stable and do not appear to have a significant role in the formation of symbiont populations relative to their distribution across the Mediterranean Sea. Additionally, all squid species examined (Sepiola affinis, S. robusta, S. ligulata, S. intermedia, and Rondeletiola minor) are genetically distinct from one another regardless of location and demonstrate very little intraspecific variation within species. These findings suggest that physical boundaries and distance in relation to population size, and not host specificity, are important factors in limiting or defining gene flow within sympatric marine squids and their associated bacterial symbionts in the Mediterranean Sea.

  13. Using the TIGR gene index databases for biological discovery.

    Science.gov (United States)

    Lee, Yuandan; Quackenbush, John

    2003-11-01

    The TIGR Gene Index web pages provide access to analyses of ESTs and gene sequences for nearly 60 species, as well as a number of resources derived from these. Each species-specific database is presented using a common format with a homepage. A variety of methods exist that allow users to search each species-specific database. Methods implemented currently include nucleotide or protein sequence queries using WU-BLAST, text-based searches using various sequence identifiers, searches by gene, tissue and library name, and searches using functional classes through Gene Ontology assignments. This protocol provides guidance for using the Gene Index Databases to extract information.

  14. Spermatogenic Cell-Specific Gene Mutation in Mice via CRISPR-Cas9.

    Science.gov (United States)

    Bai, Meizhu; Liang, Dan; Wang, Yinghua; Li, Qing; Wu, Yuxuan; Li, Jinsong

    2016-05-20

    Tissue-specific knockout technology enables the analysis of the gene function in specific tissues in adult mammals. However, conventional strategy for producing tissue-specific knockout mice is a time- and labor-consuming process, restricting rapid study of the gene function in vivo. CRISPR-Cas9 system from bacteria is a simple and efficient gene-editing technique, which has enabled rapid generation of gene knockout lines in mouse by direct injection of CRISPR-Cas9 into zygotes. Here, we demonstrate CRISPR-Cas9-mediated spermatogenic cell-specific disruption of Scp3 gene in testes in one step. We first generated transgenic mice by pronuclear injection of a plasmid containing Hspa2 promoter driving Cas9 expression and showed Cas9 specific expression in spermatogenic cells. We then produced transgenic mice carrying Hspa2 promoter driven Cas9 and constitutive expressed sgRNA targeting Scp3 gene. Male founders were infertile due to developmental arrest of spermatogenic cells while female founders could produce progeny normally. Consistently, male progeny from female founders were infertile and females could transmit the transgenes to the next generation. Our study establishes a CRISPR-Cas9-based one-step strategy to analyze the gene function in adult tissues by a temporal-spatial pattern. Copyright © 2016 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

  15. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex.

    Science.gov (United States)

    Groenewald, Marizeth; Groenewald, Johannes Z; Harrington, Thomas C; Abeln, Edwin C A; Crous, Pedro W

    2006-12-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to determine the full length mating type genes of these species. Primers were developed to amplify and sequence homologous portions of the mating type genes of additional species. Phylogenetic analyses of these sequences revealed little variation among members of the C. apii complex, whereas C. zeae-maydis and C. zeina were found to be dissimilar. The presence of both mating types in approximately even proportions in C. beticola, C. zeae-maydis and C. zeina populations, in contrast to single mating types in C. apii (MAT1) and C. apiicola (MAT2), suggests that a sexual cycle may be active in some of these species.

  16. Introgression in the Drosophila subobscura--D. Madeirensis sister species: evidence of gene flow in nuclear genes despite mitochondrial differentiation.

    Science.gov (United States)

    Herrig, Danielle K; Modrick, Alec J; Brud, Evgeny; Llopart, Ana

    2014-03-01

    Species hybridization, and thus the potential for gene flow, was once viewed as reproductive mistake. However, recent analysis based on large datasets and newly developed models suggest that gene exchange is not as rare as originally suspected. To investigate the history and speciation of the closely related species Drosophila subobscura, D. madeirensis, and D. guanche, we obtained polymorphism and divergence data for 26 regions throughout the genome, including the Y chromosome and mitochondrial DNA. We found that the D. subobscura X/autosome ratio of silent nucleotide diversity is significantly smaller than the 0.75 expected under neutrality. This pattern, if held genomewide, may reflect a faster accumulation of beneficial mutations on the X chromosome than on autosomes. We also detected evidence of gene flow in autosomal regions, while sex chromosomes remain distinct. This is consistent with the large X effect on hybrid male sterility seen in this system and the presence of two X chromosome inversions fixed between species. Overall, our data conform to chromosomal speciation models in which rearrangements are proposed to serve as gene flow barriers. Contrary to other observations in Drosophila, the mitochondrial genome appears resilient to gene flow in the presence of nuclear exchange. © 2013 The Authors. Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  17. IgM repertoire biodiversity is reduced in HIV-1 infection and systemic lupus erythematosus

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    Li eYin

    2013-11-01

    Full Text Available Background: HIV-1 infection or systemic lupus erythematosus [SLE] disrupt B cell homeostasis, reduce memory B cells, and impair function of IgG and IgM antibodies. Objective: To determine how disturbances in B cell populations producing polyclonal antibodies relate to the IgM repertoire, the IgM transcriptome in health and disease was explored at the complementarity determining region 3 [CDRH3] sequence population level. Methods: 454-deep pyrosequencing in combination with a novel analysis pipeline was applied to define populations of IGHM CDRH3 sequences based on absence or presence of somatic hypermutations [SHM] in peripheral blood B cells. Results: HIV or SLE subjects have reduced biodiversity within their IGHM transcriptome compared to healthy subjects, mainly due to a significant decrease in the number of unique combinations of alleles, although recombination machinery was intact. While major differences between sequences without or with SHM occurred among all groups, IGHD and IGHJ allele use, CDRH3 length distribution, or generation of SHM were similar among study cohorts. Antiretroviral therapy failed to normalize IGHM biodiversity in HIV-infected individuals. All subjects had a low frequency of allelic combinations within the IGHM repertoire similar to known broadly-neutralizing HIV-1 antibodies. Conclusions: Polyclonal expansion would decrease overall IgM biodiversity independent of other mechanisms for development of the B cell repertoire. Applying deep sequencing as a strategy to follow development of the IgM repertoire in health and disease provides a novel molecular assessment of multiple points along the B cell differentiation pathway that is highly sensitive for detecting perturbations within the repertoire at the population level.

  18. Identification of the two rotavirus genes determining neutralization specificities

    International Nuclear Information System (INIS)

    Offit, P.A.; Blavat, G.

    1986-01-01

    Bovine rotavirus NCDV and simian rotavirus SA-11 represent two distinct rotavirus serotypes. A genetic approach was used to determine which viral gene segments segregated with serotype-specific viral neutralization. There were 16 reassortant rotarviruses derived by coinfection of MA-104 cells in vitro with the SA-11 and NCDV strains. The parental origin of reassortant rotavirus double-stranded RNA segments was determined by gene segment mobility in polyacrylamide gels and by hybridization with radioactively labeled parental viral transcripts. The authors found that two rotavirus gene segments found previously to code for outer capsid proteins vp3 and vp7 cosegreated with virus neutralization specificities

  19. Identification of the two rotavirus genes determining neutralization specificities

    Energy Technology Data Exchange (ETDEWEB)

    Offit, P.A.; Blavat, G.

    1986-01-01

    Bovine rotavirus NCDV and simian rotavirus SA-11 represent two distinct rotavirus serotypes. A genetic approach was used to determine which viral gene segments segregated with serotype-specific viral neutralization. There were 16 reassortant rotarviruses derived by coinfection of MA-104 cells in vitro with the SA-11 and NCDV strains. The parental origin of reassortant rotavirus double-stranded RNA segments was determined by gene segment mobility in polyacrylamide gels and by hybridization with radioactively labeled parental viral transcripts. The authors found that two rotavirus gene segments found previously to code for outer capsid proteins vp3 and vp7 cosegreated with virus neutralization specificities.

  20. Genomic Resources of Three Pulsatilla Species Reveal Evolutionary Hotspots, Species-Specific Sites and Variable Plastid Structure in the Family Ranunculaceae

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    Monika Szczecińska

    2015-09-01

    Full Text Available Background: The European continent is presently colonized by nine species of the genus Pulsatilla, five of which are encountered only in mountainous regions of southwest and south-central Europe. The remaining four species inhabit lowlands in the north-central and eastern parts of the continent. Most plants of the genus Pulsatilla are rare and endangered, which is why most research efforts focused on their biology, ecology and hybridization. The objective of this study was to develop genomic resources, including complete plastid genomes and nuclear rRNA clusters, for three sympatric Pulsatilla species that are most commonly found in Central Europe. The results will supply valuable information about genetic variation, which can be used in the process of designing primers for population studies and conservation genetics research. The complete plastid genomes together with the nuclear rRNA cluster can serve as a useful tool in hybridization studies. Methodology/principal findings: Six complete plastid genomes and nuclear rRNA clusters were sequenced from three species of Pulsatilla using the Illumina sequencing technology. Four junctions between single copy regions and inverted repeats and junctions between the identified locally-collinear blocks (LCB were confirmed by Sanger sequencing. Pulsatilla genomes of 120 unique genes had a total length of approximately 161–162 kb, and 21 were duplicated in the inverted repeats (IR region. Comparative plastid genomes of newly-sequenced Pulsatilla and the previously-identified plastomes of Aconitum and Ranunculus species belonging to the family Ranunculaceae revealed several variations in the structure of the genome, but the gene content remained constant. The nuclear rRNA cluster (18S-ITS1-5.8S-ITS2-26S of studied Pulsatilla species is 5795 bp long. Among five analyzed regions of the rRNA cluster, only Internal Transcribed Spacer 2 (ITS2 enabled the molecular delimitation of closely-related Pulsatilla