WorldWideScience

Sample records for compare genomic signatures

  1. Comparative Genomics of Herpesviridae Family to Look for Potential Signatures of Human Infecting Strains

    Directory of Open Access Journals (Sweden)

    Vikas Sharma

    2016-01-01

    Full Text Available Herpesviridae family is one of the significant viral families which comprises major pathogens of a wide range of hosts. This family includes at least eight species of viruses which are known to infect humans. This family has evolved 180–220 million years ago and the present study highlights that it is still evolving and more genes can be added to the repertoire of this family. In addition, its core-genome includes important viral proteins including glycoprotein B and helicase. Most of the infections caused by human herpesviruses have no definitive cure; thus, search for new therapeutic strategies is necessary. The present study finds core-genome of human herpesviruses that differs from that of Herpesviridae family and nonhuman herpes strains of this family and might be a putative target for vaccine development. The phylogenetic reconstruction based upon the protein sequences of core gene set of Herpesviridae family reveals the sharp splits of its different subfamilies and supports the hypothesis of coevolution of viruses with their hosts. In addition, data mining for cis-elements in the genomes of human herpesviruses results in the prediction of numerous regulatory elements which can be used for regulating the expression of viral based vectors implicated in gene therapies.

  2. Comparative Genomics

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 8. Comparative Genomics - A Powerful New Tool in Biology. Anand K Bachhawat. General Article Volume 11 Issue 8 August 2006 pp 22-40. Fulltext. Click here to view fulltext PDF. Permanent link:

  3. Genomic Signatures of Sexual Conflict.

    Science.gov (United States)

    Kasimatis, Katja R; Nelson, Thomas C; Phillips, Patrick C

    2017-10-30

    Sexual conflict is a specific class of intergenomic conflict that describes the reciprocal sex-specific fitness costs generated by antagonistic reproductive interactions. The potential for sexual conflict is an inherent property of having a shared genome between the sexes and, therefore, is an extreme form of an environment-dependent fitness effect. In this way, many of the predictions from environment-dependent selection can be used to formulate expected patterns of genome evolution under sexual conflict. However, the pleiotropic and transmission constraints inherent to having alleles move across sex-specific backgrounds from generation to generation further modulate the anticipated signatures of selection. We outline methods for detecting candidate sexual conflict loci both across and within populations. Additionally, we consider the ability of genome scans to identify sexually antagonistic loci by modeling allele frequency changes within males and females due to a single generation of selection. In particular, we highlight the need to integrate genotype, phenotype, and functional information to truly distinguish sexual conflict from other forms of sexual differentiation. © The American Genetic Association 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Comparative Genomics

    Indian Academy of Sciences (India)

    An important hallmark of biological research is the aspect of 'comparisons'. As the complete genome sequences of numerous organisms have become available, the emphasis in biology has shifted to comparisons at the genome level. Indeed, the last few years have witnessed an exponential rise in the number of ...

  5. Comparative Genomics

    Indian Academy of Sciences (India)

    structions of the tree of life, drug discovery programs, func- tion predictions of hypothetical proteins and genes, regula- tory motifs and other non-coding DNA motifs, and genome ... expertise in assembling sequences. Beginning with the complete genome sequence of the bacterial pathogen Haemophilus influenzae that was ...

  6. Mapping the space of genomic signatures.

    Directory of Open Access Journals (Sweden)

    Lila Kari

    Full Text Available We propose a computational method to measure and visualize interrelationships among any number of DNA sequences allowing, for example, the examination of hundreds or thousands of complete mitochondrial genomes. An "image distance" is computed for each pair of graphical representations of DNA sequences, and the distances are visualized as a Molecular Distance Map: Each point on the map represents a DNA sequence, and the spatial proximity between any two points reflects the degree of structural similarity between the corresponding sequences. The graphical representation of DNA sequences utilized, Chaos Game Representation (CGR, is genome- and species-specific and can thus act as a genomic signature. Consequently, Molecular Distance Maps could inform species identification, taxonomic classifications and, to a certain extent, evolutionary history. The image distance employed, Structural Dissimilarity Index (DSSIM, implicitly compares the occurrences of oligomers of length up to k (herein k = 9 in DNA sequences. We computed DSSIM distances for more than 5 million pairs of complete mitochondrial genomes, and used Multi-Dimensional Scaling (MDS to obtain Molecular Distance Maps that visually display the sequence relatedness in various subsets, at different taxonomic levels. This general-purpose method does not require DNA sequence alignment and can thus be used to compare similar or vastly different DNA sequences, genomic or computer-generated, of the same or different lengths. We illustrate potential uses of this approach by applying it to several taxonomic subsets: phylum Vertebrata, (superkingdom Protista, classes Amphibia-Insecta-Mammalia, class Amphibia, and order Primates. This analysis of an extensive dataset confirms that the oligomer composition of full mtDNA sequences can be a source of taxonomic information. This method also correctly finds the mtDNA sequences most closely related to that of the anatomically modern human (the Neanderthal

  7. Analysis of dinucleotide signatures in HIV-1 subtype B genomes

    Indian Academy of Sciences (India)

    genome signature; DRAP; HIV-1; chaos game representation. Abstract. Dinucleotide usage is known to vary in the genomes of organisms. The dinucleotide usage profiles or genome signatures are similar for sequence samples taken from the same genome, but are different for taxonomically distant species. This concept of ...

  8. Comparative genomics of Lactobacillus

    Science.gov (United States)

    Kant, Ravi; Blom, Jochen; Palva, Airi; Siezen, Roland J.; de Vos, Willem M.

    2011-01-01

    Summary The genus Lactobacillus includes a diverse group of bacteria consisting of many species that are associated with fermentations of plants, meat or milk. In addition, various lactobacilli are natural inhabitants of the intestinal tract of humans and other animals. Finally, several Lactobacillus strains are marketed as probiotics as their consumption can confer a health benefit to host. Presently, 154 Lactobacillus species are known and a growing fraction of these are subject to draft genome sequencing. However, complete genome sequences are needed to provide a platform for detailed genomic comparisons. Therefore, we selected a total of 20 genomes of various Lactobacillus strains for which complete genomic sequences have been reported. These genomes had sizes varying from 1.8 to 3.3 Mb and other characteristic features, such as G+C content that ranged from 33% to 51%. The Lactobacillus pan genome was found to consist of approximately 14 000 protein‐encoding genes while all 20 genomes shared a total of 383 sets of orthologous genes that defined the Lactobacillus core genome (LCG). Based on advanced phylogeny of the proteins encoded by this LCG, we grouped the 20 strains into three main groups and defined core group genes present in all genomes of a single group, signature group genes shared in all genomes of one group but absent in all other Lactobacillus genomes, and Group‐specific ORFans present in core group genes of one group and absent in all other complete genomes. The latter are of specific value in defining the different groups of genomes. The study provides a platform for present individual comparisons as well as future analysis of new Lactobacillus genomes. PMID:21375712

  9. Ebolavirus comparative genomics

    DEFF Research Database (Denmark)

    Jun, Se-Ran; Leuze, Michael R.; Nookaew, Intawat

    2015-01-01

    The 2014 Ebola outbreak in West Africa is the largest documented for this virus. To examine the dynamics of this genome, we compare more than 100 currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms...

  10. Comparative Genomics Including the Early-Diverging Smut Fungus Ceraceosorus bombacis Reveals Signatures of Parallel Evolution within Plant and Animal Pathogens of Fungi and Oomycetes.

    Science.gov (United States)

    Sharma, Rahul; Xia, Xiaojuan; Riess, Kai; Bauer, Robert; Thines, Marco

    2015-08-27

    Ceraceosorus bombacis is an early-diverging lineage of smut fungi and a pathogen of cotton trees (Bombax ceiba). To study the evolutionary genomics of smut fungi in comparison with other fungal and oomycete pathogens, the genome of C. bombacis was sequenced and comparative genomic analyses were performed. The genome of 26.09 Mb encodes for 8,024 proteins, of which 576 are putative-secreted effector proteins (PSEPs). Orthology analysis revealed 30 ortholog PSEPs among six Ustilaginomycotina genomes, the largest groups of which are lytic enzymes, such as aspartic peptidase and glycoside hydrolase. Positive selection analyses revealed the highest percentage of positively selected PSEPs in C. bombacis compared with other Ustilaginomycotina genomes. Metabolic pathway analyses revealed the absence of genes encoding for nitrite and nitrate reductase in the genome of the human skin pathogen Malassezia globosa, but these enzymes are present in the sequenced plant pathogens in smut fungi. Interestingly, these genes are also absent in cultivable oomycete animal pathogens, while nitrate reductase has been lost in cultivable oomycete plant pathogens. Similar patterns were also observed for obligate biotrophic and hemi-biotrophic fungal and oomycete pathogens. Furthermore, it was found that both fungal and oomycete animal pathogen genomes are lacking cutinases and pectinesterases. Overall, these findings highlight the parallel evolution of certain genomic traits, revealing potential common evolutionary trajectories among fungal and oomycete pathogens, shaping the pathogen genomes according to their lifestyle. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  11. Genome signature analysis of thermal virus metagenomes reveals Archaea and thermophilic signatures

    Directory of Open Access Journals (Sweden)

    Pride David T

    2008-09-01

    Full Text Available Abstract Background Metagenomic analysis provides a rich source of biological information for otherwise intractable viral communities. However, study of viral metagenomes has been hampered by its nearly complete reliance on BLAST algorithms for identification of DNA sequences. We sought to develop algorithms for examination of viral metagenomes to identify the origin of sequences independent of BLAST algorithms. We chose viral metagenomes obtained from two hot springs, Bear Paw and Octopus, in Yellowstone National Park, as they represent simple microbial populations where comparatively large contigs were obtained. Thermal spring metagenomes have high proportions of sequences without significant Genbank homology, which has hampered identification of viruses and their linkage with hosts. To analyze each metagenome, we developed a method to classify DNA fragments using genome signature-based phylogenetic classification (GSPC, where metagenomic fragments are compared to a database of oligonucleotide signatures for all previously sequenced Bacteria, Archaea, and viruses. Results From both Bear Paw and Octopus hot springs, each assembled contig had more similarity to other metagenome contigs than to any sequenced microbial genome based on GSPC analysis, suggesting a genome signature common to each of these extreme environments. While viral metagenomes from Bear Paw and Octopus share some similarity, the genome signatures from each locale are largely unique. GSPC using a microbial database predicts most of the Octopus metagenome has archaeal signatures, while bacterial signatures predominate in Bear Paw; a finding consistent with those of Genbank BLAST. When using a viral database, the majority of the Octopus metagenome is predicted to belong to archaeal virus Families Globuloviridae and Fuselloviridae, while none of the Bear Paw metagenome is predicted to belong to archaeal viruses. As expected, when microbial and viral databases are combined, each of

  12. Genome signature analysis of thermal virus metagenomes reveals Archaea and thermophilic signatures.

    Science.gov (United States)

    Pride, David T; Schoenfeld, Thomas

    2008-09-17

    Metagenomic analysis provides a rich source of biological information for otherwise intractable viral communities. However, study of viral metagenomes has been hampered by its nearly complete reliance on BLAST algorithms for identification of DNA sequences. We sought to develop algorithms for examination of viral metagenomes to identify the origin of sequences independent of BLAST algorithms. We chose viral metagenomes obtained from two hot springs, Bear Paw and Octopus, in Yellowstone National Park, as they represent simple microbial populations where comparatively large contigs were obtained. Thermal spring metagenomes have high proportions of sequences without significant Genbank homology, which has hampered identification of viruses and their linkage with hosts. To analyze each metagenome, we developed a method to classify DNA fragments using genome signature-based phylogenetic classification (GSPC), where metagenomic fragments are compared to a database of oligonucleotide signatures for all previously sequenced Bacteria, Archaea, and viruses. From both Bear Paw and Octopus hot springs, each assembled contig had more similarity to other metagenome contigs than to any sequenced microbial genome based on GSPC analysis, suggesting a genome signature common to each of these extreme environments. While viral metagenomes from Bear Paw and Octopus share some similarity, the genome signatures from each locale are largely unique. GSPC using a microbial database predicts most of the Octopus metagenome has archaeal signatures, while bacterial signatures predominate in Bear Paw; a finding consistent with those of Genbank BLAST. When using a viral database, the majority of the Octopus metagenome is predicted to belong to archaeal virus Families Globuloviridae and Fuselloviridae, while none of the Bear Paw metagenome is predicted to belong to archaeal viruses. As expected, when microbial and viral databases are combined, each of the Octopus and Bear Paw metagenomic contigs

  13. Comparing Patterns of Natural Selection across Species Using Selective Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Jesse; Alm, Eric J.

    2007-12-01

    Comparing gene expression profiles over many different conditions has led to insights that were not obvious from single experiments. In the same way, comparing patterns of natural selection across a set of ecologically distinct species may extend what can be learned from individual genome-wide surveys. Toward this end, we show how variation in protein evolutionary rates, after correcting for genome-wide effects such as mutation rate and demographic factors, can be used to estimate the level and types of natural selection acting on genes across different species. We identify unusually rapidly and slowly evolving genes, relative to empirically derived genome-wide and gene family-specific background rates for 744 core protein families in 30 c-proteobacterial species. We describe the pattern of fast or slow evolution across species as the"selective signature" of a gene. Selective signatures represent aprofile of selection across species that is predictive of gene function: pairs of genes with correlated selective signatures are more likely to share the same cellular function, and genes in the same pathway can evolve in concert. For example,glycolysis and phenylalanine metabolism genes evolve rapidly in Idiomarina loihiensis, mirroring an ecological shift in carbon source from sugars to amino acids. In a broader context, our results suggest that the genomic landscape is organized into functional modules even at the level of natural selection, and thus it may be easier than expected to understand the complex evolutionary pressures on a cell.

  14. Comparing Patterns of Natural Selection Across Species Using Selective Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Alm, Eric J.; Shapiro, B. Jesse; Alm, Eric J.

    2007-12-18

    Comparing gene expression profiles over many different conditions has led to insights that were not obvious from single experiments. In the same way, comparing patterns of natural selection across a set of ecologically distinct species may extend what can be learned from individual genome-wide surveys. Toward this end, we show how variation in protein evolutionary rates, after correcting for genome-wide effects such as mutation rate and demographic factors, can be used to estimate the level and types of natural selection acting on genes across different species. We identify unusually rapidly and slowly evolving genes, relative to empirically derived genome-wide and gene family-specific background rates for 744 core protein families in 30 gamma-proteobacterial species. We describe the pattern of fast or slow evolution across species as the 'selective signature' of a gene. Selective signatures represent a profile of selection across species that is predictive of gene function: pairs of genes with correlated selective signatures are more likely to share the same cellular function, and genes in the same pathway can evolve in concert. For example, glycolysis and phenylalanine metabolism genes evolve rapidly in Idiomarina loihiensis, mirroring an ecological shift in carbon source from sugars to amino acids. In a broader context, our results suggest that the genomic landscape is organized into functional modules even at the level of natural selection, and thus it may be easier than expected to understand the complex evolutionary pressures on a cell.

  15. Comparing patterns of natural selection across species using selective signatures.

    Directory of Open Access Journals (Sweden)

    B Jesse Shapiro

    2008-02-01

    Full Text Available Comparing gene expression profiles over many different conditions has led to insights that were not obvious from single experiments. In the same way, comparing patterns of natural selection across a set of ecologically distinct species may extend what can be learned from individual genome-wide surveys. Toward this end, we show how variation in protein evolutionary rates, after correcting for genome-wide effects such as mutation rate and demographic factors, can be used to estimate the level and types of natural selection acting on genes across different species. We identify unusually rapidly and slowly evolving genes, relative to empirically derived genome-wide and gene family-specific background rates for 744 core protein families in 30 gamma-proteobacterial species. We describe the pattern of fast or slow evolution across species as the "selective signature" of a gene. Selective signatures represent a profile of selection across species that is predictive of gene function: pairs of genes with correlated selective signatures are more likely to share the same cellular function, and genes in the same pathway can evolve in concert. For example, glycolysis and phenylalanine metabolism genes evolve rapidly in Idiomarina loihiensis, mirroring an ecological shift in carbon source from sugars to amino acids. In a broader context, our results suggest that the genomic landscape is organized into functional modules even at the level of natural selection, and thus it may be easier than expected to understand the complex evolutionary pressures on a cell.

  16. Comparative Genome Viewer

    International Nuclear Information System (INIS)

    Molineris, I.; Sales, G.

    2009-01-01

    The amount of information about genomes, both in the form of complete sequences and annotations, has been exponentially increasing in the last few years. As a result there is the need for tools providing a graphical representation of such information that should be comprehensive and intuitive. Visual representation is especially important in the comparative genomics field since it should provide a combined view of data belonging to different genomes. We believe that existing tools are limited in this respect as they focus on a single genome at a time (conservation histograms) or compress alignment representation to a single dimension. We have therefore developed a web-based tool called Comparative Genome Viewer (Cgv): it integrates a bidimensional representation of alignments between two regions, both at small and big scales, with the richness of annotations present in other genome browsers. We give access to our system through a web-based interface that provides the user with an interactive representation that can be updated in real time using the mouse to move from region to region and to zoom in on interesting details.

  17. Comparative Genomics of Cryptosporidium

    Directory of Open Access Journals (Sweden)

    Aurélien J. Mazurie

    2013-01-01

    Full Text Available Until recently, the apicomplexan parasites, Cryptosporidium hominis and C. parvum, were considered the same species. However, the two parasites, now considered distinct species, exhibit significant differences in host range, infectivity, and pathogenicity, and their sequenced genomes exhibit only 95–97% identity. The availability of the complete genome sequences of these organisms provides the potential to identify the genetic variations that are responsible for the phenotypic differences between the two parasites. We compared the genome organization and structure, gene composition, the metabolic and other pathways, and the local sequence identity between the genes of these two Cryptosporidium species. Our observations show that the phenotypic differences between C. hominis and C. parvum are not due to gross genome rearrangements, structural alterations, gene deletions or insertions, metabolic capabilities, or other obvious genomic alterations. Rather, the results indicate that these genomes exhibit a remarkable structural and compositional conservation and suggest that the phenotypic differences observed are due to subtle variations in the sequences of proteins that act at the interface between the parasite and its host.

  18. The genomic signature of parallel adaptation from shared genetic variation.

    Science.gov (United States)

    Roesti, Marius; Gavrilets, Sergey; Hendry, Andrew P; Salzburger, Walter; Berner, Daniel

    2014-08-01

    Parallel adaptation is common and may often occur from shared genetic variation, but the genomic consequences of this process remain poorly understood. We first use individual-based simulations to demonstrate that comparisons between populations adapted in parallel to similar environments from shared variation reveal a characteristic genomic signature around a selected locus: a low-divergence valley centred at the locus and flanked by twin peaks of high divergence. This signature is initiated by the hitchhiking of haplotype tracts differing between derived populations in the broader neighbourhood of the selected locus (driving the high-divergence twin peaks) and shared haplotype tracts in the tight neighbourhood of the locus (driving the low-divergence valley). This initial hitchhiking signature is reinforced over time because the selected locus acts as a barrier to gene flow from the source to the derived populations, thus promoting divergence by drift in its close neighbourhood. We next empirically confirm the peak-valley-peak signature by combining targeted and RAD sequence data at three candidate adaptation genes in multiple marine (source) and freshwater (derived) populations of threespine stickleback. Finally, we use a genome-wide screen for the peak-valley-peak signature to discover additional genome regions involved in parallel marine-freshwater divergence. Our findings offer a new explanation for heterogeneous genomic divergence and thus challenge the standard view that peaks in population divergence harbour divergently selected loci and that low-divergence regions result from balancing selection or localized introgression. We anticipate that genome scans for peak-valley-peak divergence signatures will promote the discovery of adaptation genes in other organisms. © 2014 John Wiley & Sons Ltd.

  19. Signatures of selection in tilapia revealed by whole genome resequencing.

    Science.gov (United States)

    Xia, Jun Hong; Bai, Zhiyi; Meng, Zining; Zhang, Yong; Wang, Le; Liu, Feng; Jing, Wu; Wan, Zi Yi; Li, Jiale; Lin, Haoran; Yue, Gen Hua

    2015-09-16

    Natural selection and selective breeding for genetic improvement have left detectable signatures within the genome of a species. Identification of selection signatures is important in evolutionary biology and for detecting genes that facilitate to accelerate genetic improvement. However, selection signatures, including artificial selection and natural selection, have only been identified at the whole genome level in several genetically improved fish species. Tilapia is one of the most important genetically improved fish species in the world. Using next-generation sequencing, we sequenced the genomes of 47 tilapia individuals. We identified a total of 1.43 million high-quality SNPs and found that the LD block sizes ranged from 10-100 kb in tilapia. We detected over a hundred putative selective sweep regions in each line of tilapia. Most selection signatures were located in non-coding regions of the tilapia genome. The Wnt signaling, gonadotropin-releasing hormone receptor and integrin signaling pathways were under positive selection in all improved tilapia lines. Our study provides a genome-wide map of genetic variation and selection footprints in tilapia, which could be important for genetic studies and accelerating genetic improvement of tilapia.

  20. Comparative RNA genomics

    DEFF Research Database (Denmark)

    Backofen, Rolf; Gorodkin, Jan; Hofacker, Ivo L.

    2018-01-01

    small RNAs is their reliance of conserved secondary structures. Large scale sequencing projects, on the other hand, have profoundly changed our understanding of eukaryotic genomes. Pervasively transcribed, they give rise to a plethora of large and evolutionarily extremely flexible noncoding RNAs...... that exert a vastly diverse array of molecule functions. In this chapter we provide a—necessarily incomplete—overview of the current state of comparative analysis of noncoding RNAs, emphasizing computational approaches as a means to gain a global picture of the modern RNA world....

  1. Phytozome Comparative Plant Genomics Portal

    Energy Technology Data Exchange (ETDEWEB)

    Goodstein, David; Batra, Sajeev; Carlson, Joseph; Hayes, Richard; Phillips, Jeremy; Shu, Shengqiang; Schmutz, Jeremy; Rokhsar, Daniel

    2014-09-09

    The Dept. of Energy Joint Genome Institute is a genomics user facility supporting DOE mission science in the areas of Bioenergy, Carbon Cycling, and Biogeochemistry. The Plant Program at the JGI applies genomic, analytical, computational and informatics platforms and methods to: 1. Understand and accelerate the improvement (domestication) of bioenergy crops 2. Characterize and moderate plant response to climate change 3. Use comparative genomics to identify constrained elements and infer gene function 4. Build high quality genomic resource platforms of JGI Plant Flagship genomes for functional and experimental work 5. Expand functional genomic resources for Plant Flagship genomes

  2. Analysis of dinucleotide signatures in HIV-1 subtype B genomes

    Indian Academy of Sciences (India)

    ... AIDS, have been carried out to analyse the variation in genome signatures of the virus from 1983 to 2007.We show statistically significant temporal variations in some dinucleotide patterns highlighting the selective evolution of the dinucleotide profiles of HIV-1 subtype B, possibly a consequence of host specific selection.

  3. Defining the genomic signature of the parous breast

    Directory of Open Access Journals (Sweden)

    Peri Suraj

    2012-10-01

    Full Text Available Abstract Background It is accepted that a woman's lifetime risk of developing breast cancer after menopause is reduced by early full term pregnancy and multiparity. This phenomenon is thought to be associated with the development and differentiation of the breast during pregnancy. Methods In order to understand the underlying molecular mechanisms of pregnancy induced breast cancer protection, we profiled and compared the transcriptomes of normal breast tissue biopsies from 71 parous (P and 42 nulliparous (NP healthy postmenopausal women using Affymetrix Human Genome U133 Plus 2.0 arrays. To validate the results, we performed real time PCR and immunohistochemistry. Results We identified 305 differentially expressed probesets (208 distinct genes. Of these, 267 probesets were up- and 38 down-regulated in parous breast samples; bioinformatics analysis using gene ontology enrichment revealed that up-regulated genes in the parous breast represented biological processes involving differentiation and development, anchoring of epithelial cells to the basement membrane, hemidesmosome and cell-substrate junction assembly, mRNA and RNA metabolic processes and RNA splicing machinery. The down-regulated genes represented biological processes that comprised cell proliferation, regulation of IGF-like growth factor receptor signaling, somatic stem cell maintenance, muscle cell differentiation and apoptosis. Conclusions This study suggests that the differentiation of the breast imprints a genomic signature that is centered in the mRNA processing reactome. These findings indicate that pregnancy may induce a safeguard mechanism at post-transcriptional level that maintains the fidelity of the transcriptional process.

  4. Whole-genome reconstruction and mutational signatures in gastric cancer.

    Science.gov (United States)

    Nagarajan, Niranjan; Bertrand, Denis; Hillmer, Axel M; Zang, Zhi Jiang; Yao, Fei; Jacques, Pierre-Étienne; Teo, Audrey S M; Cutcutache, Ioana; Zhang, Zhenshui; Lee, Wah Heng; Sia, Yee Yen; Gao, Song; Ariyaratne, Pramila N; Ho, Andrea; Woo, Xing Yi; Veeravali, Lavanya; Ong, Choon Kiat; Deng, Niantao; Desai, Kartiki V; Khor, Chiea Chuen; Hibberd, Martin L; Shahab, Atif; Rao, Jaideepraj; Wu, Mengchu; Teh, Ming; Zhu, Feng; Chin, Sze Yung; Pang, Brendan; So, Jimmy B Y; Bourque, Guillaume; Soong, Richie; Sung, Wing-Kin; Tean Teh, Bin; Rozen, Steven; Ruan, Xiaoan; Yeoh, Khay Guan; Tan, Patrick B O; Ruan, Yijun

    2012-12-13

    Gastric cancer is the second highest cause of global cancer mortality. To explore the complete repertoire of somatic alterations in gastric cancer, we combined massively parallel short read and DNA paired-end tag sequencing to present the first whole-genome analysis of two gastric adenocarcinomas, one with chromosomal instability and the other with microsatellite instability. Integrative analysis and de novo assemblies revealed the architecture of a wild-type KRAS amplification, a common driver event in gastric cancer. We discovered three distinct mutational signatures in gastric cancer--against a genome-wide backdrop of oxidative and microsatellite instability-related mutational signatures, we identified the first exome-specific mutational signature. Further characterization of the impact of these signatures by combining sequencing data from 40 complete gastric cancer exomes and targeted screening of an additional 94 independent gastric tumors uncovered ACVR2A, RPL22 and LMAN1 as recurrently mutated genes in microsatellite instability-positive gastric cancer and PAPPA as a recurrently mutated gene in TP53 wild-type gastric cancer. These results highlight how whole-genome cancer sequencing can uncover information relevant to tissue-specific carcinogenesis that would otherwise be missed from exome-sequencing data.

  5. A Signature Comparing Android Mobile Application Utilizing Feature Extracting Algorithms

    Directory of Open Access Journals (Sweden)

    Paul Grafilon

    2017-08-01

    Full Text Available The paper presented one of the application that can be done using smartphones camera. Nowadays forgery is one of the most undetected crimes. With the forensic technology used today it is still difficult for authorities to compare and define what a real signature is and what a forged signature is. A signature is a legal representation of a person. All transactions are based on a signature. Forgers may use a signature to sign illegal contracts and withdraw from bank accounts undetected. A signature can also be forged during election periods for repeated voting. Addressing the issues a signature should always be secure. Signature verification is a reduced problem that still poses a real challenge for researchers. The literature on signature verification is quite extensive and shows two main areas of research off-line and on-line systems. Off-line systems deal with a static image of the signature i.e. the result of the action of signing while on-line systems work on the dynamic process of generating the signature i.e. the action of signing itself. The researchers have found a way to resolve the concerns. A mobile application that integrates the camera to take a picture of a signature analyzes it and compares it to other signatures for verification. It will exist to help citizens to be more cautious and aware with issues regarding the signatures. This might also be relevant to help organizations and institutions such as banks and insurance companies in verifying signatures that may avoid unwanted transactions and identity theft. Furthermore this might help the authorities in the never ending battle against crime especially against forgers and thieves. The project aimed to design and develop a mobile application that integrates the smartphone camera for verifying and comparing signatures for security using the best algorithm possible. As the result of the development the said smartphone camera application is functional and reliable.

  6. Design of Genomic Signatures of Pathogen Identification & Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Slezak, T; Gardner, S; Allen, J; Vitalis, E; Jaing, C

    2010-02-09

    This chapter will address some of the many issues associated with the identification of signatures based on genomic DNA/RNA, which can be used to identify and characterize pathogens for biodefense and microbial forensic goals. For the purposes of this chapter, we define a signature as one or more strings of contiguous genomic DNA or RNA bases that are sufficient to identify a pathogenic target of interest at the desired resolution and which could be instantiated with particular detection chemistry on a particular platform. The target may be a whole organism, an individual functional mechanism (e.g., a toxin gene), or simply a nucleic acid indicative of the organism. The desired resolution will vary with each program's goals but could easily range from family to genus to species to strain to isolate. The resolution may not be taxonomically based but rather pan-mechanistic in nature: detecting virulence or antibiotic-resistance genes shared by multiple microbes. Entire industries exist around different detection chemistries and instrument platforms for identification of pathogens, and we will only briefly mention a few of the techniques that we have used at Lawrence Livermore National Laboratory (LLNL) to support our biosecurity-related work since 2000. Most nucleic acid based detection chemistries involve the ability to isolate and amplify the signature target region(s), combined with a technique to detect the amplification. Genomic signature based identification techniques have the advantage of being precise, highly sensitive and relatively fast in comparison to biochemical typing methods and protein signatures. Classical biochemical typing methods were developed long before knowledge of DNA and resulted in dozens of tests (Gram's stain, differential growth characteristics media, etc.) that could be used to roughly characterize the major known pathogens (of course some are uncultivable). These tests could take many days to complete and precise resolution

  7. Comparative Genomics in Homo sapiens.

    Science.gov (United States)

    Oti, Martin; Sammeth, Michael

    2018-01-01

    Genomes can be compared at different levels of divergence, either between species or within species. Within species genomes can be compared between different subpopulations, such as human subpopulations from different continents. Investigating the genomic differences between different human subpopulations is important when studying complex diseases that are affected by many genetic variants, as the variants involved can differ between populations. The 1000 Genomes Project collected genome-scale variation data for 2504 human individuals from 26 different populations, enabling a systematic comparison of variation between human subpopulations. In this chapter, we present step-by-step a basic protocol for the identification of population-specific variants employing the 1000 Genomes data. These variants are subsequently further investigated for those that affect the proteome or RNA splice sites, to investigate potentially biologically relevant differences between the populations.

  8. Comparative genomic hybridization: practical guidelines.

    NARCIS (Netherlands)

    Jeuken, J.W.M.; Sprenger, S.H.; Wesseling, P.

    2002-01-01

    Comparative genomic hybridization (CGH) is a technique used to identify copy number changes throughout a genome. Until now, hundreds of CGH studies have been published reporting chromosomal imbalances in a large variety of human neoplasms. Additionally, technical improvements of specific steps in a

  9. Comparative Genomics of the Cucurbitaceae

    Science.gov (United States)

    The genome size for watermelon, melon, cucumber, and pumpkin is 425, 454, 367, and 502 Mbp, respectively, and considered medium size as compared with most other crops. Whole-genome duplication is common in angiosperm plants. Research has revealed a paleohexaploidy (') event in the common ancestor of...

  10. Signatures of adaptation to plant parasitism in nematode genomes.

    Science.gov (United States)

    Bird, David McK; Jones, John T; Opperman, Charles H; Kikuchi, Taisei; Danchin, Etienne G J

    2015-02-01

    Plant-parasitic nematodes cause considerable damage to global agriculture. The ability to parasitize plants is a derived character that appears to have independently emerged several times in the phylum Nematoda. Morphological convergence to feeding style has been observed, but whether this is emergent from molecular convergence is less obvious. To address this, we assess whether genomic signatures can be associated with plant parasitism by nematodes. In this review, we report genomic features and characteristics that appear to be common in plant-parasitic nematodes while absent or rare in animal parasites, predators or free-living species. Candidate horizontal acquisitions of parasitism genes have systematically been found in all plant-parasitic species investigated at the sequence level. Presence of peptides that mimic plant hormones also appears to be a trait of plant-parasitic species. Annotations of the few genomes of plant-parasitic nematodes available to date have revealed a set of apparently species-specific genes on every occasion. Effector genes, important for parasitism are frequently found among those species-specific genes, indicating poor overlap. Overall, nematodes appear to have developed convergent genomic solutions to adapt to plant parasitism.

  11. Comparative genomics for biodiversity conservation

    Directory of Open Access Journals (Sweden)

    Catherine E. Grueber

    2015-01-01

    Full Text Available Genomic approaches are gathering momentum in biology and emerging opportunities lie in the creative use of comparative molecular methods for revealing the processes that influence diversity of wildlife. However, few comparative genomic studies are performed with explicit and specific objectives to aid conservation of wild populations. Here I provide a brief overview of comparative genomic approaches that offer specific benefits to biodiversity conservation. Because conservation examples are few, I draw on research from other areas to demonstrate how comparing genomic data across taxa may be used to inform the characterisation of conservation units and studies of hybridisation, as well as studies that provide conservation outcomes from a better understanding of the drivers of divergence. A comparative approach can also provide valuable insight into the threatening processes that impact rare species, such as emerging diseases and their management in conservation. In addition to these opportunities, I note areas where additional research is warranted. Overall, comparing and contrasting the genomic composition of threatened and other species provide several useful tools for helping to preserve the molecular biodiversity of the global ecosystem.

  12. Strong signatures of selection in the domestic pig genome

    DEFF Research Database (Denmark)

    Rubin, Carl-Johan; Megens, Hendrik-Jan; Barrio, Alvaro Martinez

    2012-01-01

    . We found an excess of derived nonsynonymous substitutions in domestic pigs, most likely reflecting both positive selection and relaxed purifying selection after domestication. Our analysis of structural variation revealed four duplications at the KIT locus that were exclusively present in white......Domestication of wild boar (Sus scrofa) and subsequent selection have resulted in dramatic phenotypic changes in domestic pigs for a number of traits, including behavior, body composition, reproduction, and coat color. Here we have used whole-genome resequencing to reveal some of the loci...... that underlie phenotypic evolution in European domestic pigs. Selective sweep analyses revealed strong signatures of selection at three loci harboring quantitative trait loci that explain a considerable part of one of the most characteristic morphological changes in the domestic pig—the elongation of the back...

  13. IDENTIFICATION AND ANALYSIS OF BACTERIAL GENOMIC METABOLIC SIGNATURES.

    Science.gov (United States)

    Bowerman, Nathaniel; Tintle, Nathan; Dejongh, Matthew; Best, Aaron A

    2017-01-01

    With continued rapid growth in the number and quality of fully sequenced and accurately annotated bacterial genomes, we have unprecedented opportunities to understand metabolic diversity. We selected 101 diverse and representative completely sequenced bacteria and implemented a manual curation effort to identify 846 unique metabolic variants present in these bacteria. The presence or absence of these variants act as a metabolic signature for each of the bacteria, which can then be used to understand similarities and differences between and across bacterial groups. We propose a novel and robust method of summarizing metabolic diversity using metabolic signatures and use this method to generate a metabolic tree, clustering metabolically similar organisms. Resulting analysis of the metabolic tree confirms strong associations with well-established biological results along with direct insight into particular metabolic variants which are most predictive of metabolic diversity. The positive results of this manual curation effort and novel method development suggest that future work is needed to further expand the set of bacteria to which this approach is applied and use the resulting tree to test broad questions about metabolic diversity and complexity across the bacterial tree of life.

  14. Enhancer Identification through Comparative Genomics

    Energy Technology Data Exchange (ETDEWEB)

    Visel, Axel; Bristow, James; Pennacchio, Len A.

    2006-10-01

    With the availability of genomic sequence from numerousvertebrates, a paradigm shift has occurred in the identification ofdistant-acting gene regulatory elements. In contrast to traditionalgene-centric studies in which investigators randomly scanned genomicfragments that flank genes of interest in functional assays, the modernapproach begins electronically with publicly available comparativesequence datasets that provide investigators with prioritized lists ofputative functional sequences based on their evolutionary conservation.However, although a large number of tools and resources are nowavailable, application of comparative genomic approaches remains far fromtrivial. In particular, it requires users to dynamically consider thespecies and methods for comparison depending on the specific biologicalquestion under investigation. While there is currently no single generalrule to this end, it is clear that when applied appropriately,comparative genomic approaches exponentially increase our power ingenerating biological hypotheses for subsequent experimentaltesting.

  15. Three Prochlorococcus cyanophage genomes: signature features and ecological interpretations.

    Directory of Open Access Journals (Sweden)

    Matthew B Sullivan

    2005-05-01

    Full Text Available The oceanic cyanobacteria Prochlorococcus are globally important, ecologically diverse primary producers. It is thought that their viruses (phages mediate population sizes and affect the evolutionary trajectories of their hosts. Here we present an analysis of genomes from three Prochlorococcus phages: a podovirus and two myoviruses. The morphology, overall genome features, and gene content of these phages suggest that they are quite similar to T7-like (P-SSP7 and T4-like (P-SSM2 and P-SSM4 phages. Using the existing phage taxonomic framework as a guideline, we examined genome sequences to establish "core" genes for each phage group. We found the podovirus contained 15 of 26 core T7-like genes and the two myoviruses contained 43 and 42 of 75 core T4-like genes. In addition to these core genes, each genome contains a significant number of "cyanobacterial" genes, i.e., genes with significant best BLAST hits to genes found in cyanobacteria. Some of these, we speculate, represent "signature" cyanophage genes. For example, all three phage genomes contain photosynthetic genes (psbA, hliP that are thought to help maintain host photosynthetic activity during infection, as well as an aldolase family gene (talC that could facilitate alternative routes of carbon metabolism during infection. The podovirus genome also contains an integrase gene (int and other features that suggest it is capable of integrating into its host. If indeed it is, this would be unprecedented among cultured T7-like phages or marine cyanophages and would have significant evolutionary and ecological implications for phage and host. Further, both myoviruses contain phosphate-inducible genes (phoH and pstS that are likely to be important for phage and host responses to phosphate stress, a commonly limiting nutrient in marine systems. Thus, these marine cyanophages appear to be variations of two well-known phages-T7 and T4-but contain genes that, if functional, reflect adaptations for

  16. Genomic signatures of strain selection and enhancement in Bacillus atrophaeus var. globigii, a historical biowarfare simulant.

    Directory of Open Access Journals (Sweden)

    Henry S Gibbons

    Full Text Available BACKGROUND: Despite the decades-long use of Bacillus atrophaeus var. globigii (BG as a simulant for biological warfare (BW agents, knowledge of its genome composition is limited. Furthermore, the ability to differentiate signatures of deliberate adaptation and selection from natural variation is lacking for most bacterial agents. We characterized a lineage of BGwith a long history of use as a simulant for BW operations, focusing on classical bacteriological markers, metabolic profiling and whole-genome shotgun sequencing (WGS. RESULTS: Archival strains and two "present day" type strains were compared to simulant strains on different laboratory media. Several of the samples produced multiple colony morphotypes that differed from that of an archival isolate. To trace the microevolutionary history of these isolates, we obtained WGS data for several archival and present-day strains and morphotypes. Bacillus-wide phylogenetic analysis identified B. subtilis as the nearest neighbor to B. atrophaeus. The genome of B. atrophaeus is, on average, 86% identical to B. subtilis on the nucleotide level. WGS of variants revealed that several strains were mixed but highly related populations and uncovered a progressive accumulation of mutations among the "military" isolates. Metabolic profiling and microscopic examination of bacterial cultures revealed enhanced growth of "military" isolates on lactate-containing media, and showed that the "military" strains exhibited a hypersporulating phenotype. CONCLUSIONS: Our analysis revealed the genomic and phenotypic signatures of strain adaptation and deliberate selection for traits that were desirable in a simulant organism. Together, these results demonstrate the power of whole-genome and modern systems-level approaches to characterize microbial lineages to develop and validate forensic markers for strain discrimination and reveal signatures of deliberate adaptation.

  17. Genome-wide selection signatures in Pinzgau cattle

    Directory of Open Access Journals (Sweden)

    Radovan Kasarda

    2015-08-01

    Full Text Available The aim of this study was to identify the evidence of recent selection based on estimation of the integrated Haplotype Score (iHS, population differentiation index (FST and characterize affected regions near QTL associated with traits under strong selection in Pinzgau cattle. In total 21 Austrian and 19 Slovak purebreed bulls genotyped with Illumina bovineHD and  bovineSNP50 BeadChip were used to identify genomic regions under selection. Only autosomal loci with call rate higher than 90%, minor allele frequency higher than 0.01 and Hardy-Weinberg equlibrium limit of 0.001 were included in the subsequent analyses of selection sweeps presence. The final dataset was consisted from 30538 SNPs with 81.86 kb average adjacent SNPs spacing. The iHS score were averaged into non-overlapping 500 kb segments across the genome. The FST values were also plotted against genome position based on sliding windows approach and averaged over 8 consecutive SNPs. Based on integrated Haplotype Score evaluation only 7 regions with iHS score higher than 1.7 was found. The average iHS score observed for each adjacent syntenic regions indicated slight effect of recent selection in analysed group of Pinzgau bulls. The level of genetic differentiation between Austrian and Slovak bulls estimated based on FST index was low. Only 24% of FST values calculated for each SNP was greather than 0.01. By using sliding windows approach was found that 5% of analysed windows had higher value than 0.01. Our results indicated use of similar selection scheme in breeding programs of Slovak and Austrian Pinzgau bulls. The evidence for genome-wide association between signatures of selection and regions affecting complex traits such as milk production was insignificant, because the loci in segments identified as affected by selection were very distant from each other. Identification of genomic regions that may be under pressure of selection for phenotypic traits to better understanding of the

  18. Population genomic scan for candidate signatures of balancing selection to guide antigen characterization in malaria parasites.

    Directory of Open Access Journals (Sweden)

    Alfred Amambua-Ngwa

    Full Text Available Acquired immunity in vertebrates maintains polymorphisms in endemic pathogens, leading to identifiable signatures of balancing selection. To comprehensively survey for genes under such selection in the human malaria parasite Plasmodium falciparum, we generated paired-end short-read sequences of parasites in clinical isolates from an endemic Gambian population, which were mapped to the 3D7 strain reference genome to yield high-quality genome-wide coding sequence data for 65 isolates. A minority of genes did not map reliably, including the hypervariable var, rifin, and stevor families, but 5,056 genes (90.9% of all in the genome had >70% sequence coverage with minimum read depth of 5 for at least 50 isolates, of which 2,853 genes contained 3 or more single nucleotide polymorphisms (SNPs for analysis of polymorphic site frequency spectra. Against an overall background of negatively skewed frequencies, as expected from historical population expansion combined with purifying selection, the outlying minority of genes with signatures indicating exceptionally intermediate frequencies were identified. Comparing genes with different stage-specificity, such signatures were most common in those with peak expression at the merozoite stage that invades erythrocytes. Members of clag, PfMC-2TM, surfin, and msp3-like gene families were highly represented, the strongest signature being in the msp3-like gene PF10_0355. Analysis of msp3-like transcripts in 45 clinical and 11 laboratory adapted isolates grown to merozoite-containing schizont stages revealed surprisingly low expression of PF10_0355. In diverse clonal parasite lines the protein product was expressed in a minority of mature schizonts (<1% in most lines and ∼10% in clone HB3, and eight sub-clones of HB3 cultured separately had an intermediate spectrum of positive frequencies (0.9 to 7.5%, indicating phase variable expression of this polymorphic antigen. This and other identified targets of balancing

  19. Genome analysis of the platypus reveals unique signatures of evolution.

    Science.gov (United States)

    Warren, Wesley C; Hillier, LaDeana W; Marshall Graves, Jennifer A; Birney, Ewan; Ponting, Chris P; Grützner, Frank; Belov, Katherine; Miller, Webb; Clarke, Laura; Chinwalla, Asif T; Yang, Shiaw-Pyng; Heger, Andreas; Locke, Devin P; Miethke, Pat; Waters, Paul D; Veyrunes, Frédéric; Fulton, Lucinda; Fulton, Bob; Graves, Tina; Wallis, John; Puente, Xose S; López-Otín, Carlos; Ordóñez, Gonzalo R; Eichler, Evan E; Chen, Lin; Cheng, Ze; Deakin, Janine E; Alsop, Amber; Thompson, Katherine; Kirby, Patrick; Papenfuss, Anthony T; Wakefield, Matthew J; Olender, Tsviya; Lancet, Doron; Huttley, Gavin A; Smit, Arian F A; Pask, Andrew; Temple-Smith, Peter; Batzer, Mark A; Walker, Jerilyn A; Konkel, Miriam K; Harris, Robert S; Whittington, Camilla M; Wong, Emily S W; Gemmell, Neil J; Buschiazzo, Emmanuel; Vargas Jentzsch, Iris M; Merkel, Angelika; Schmitz, Juergen; Zemann, Anja; Churakov, Gennady; Kriegs, Jan Ole; Brosius, Juergen; Murchison, Elizabeth P; Sachidanandam, Ravi; Smith, Carly; Hannon, Gregory J; Tsend-Ayush, Enkhjargal; McMillan, Daniel; Attenborough, Rosalind; Rens, Willem; Ferguson-Smith, Malcolm; Lefèvre, Christophe M; Sharp, Julie A; Nicholas, Kevin R; Ray, David A; Kube, Michael; Reinhardt, Richard; Pringle, Thomas H; Taylor, James; Jones, Russell C; Nixon, Brett; Dacheux, Jean-Louis; Niwa, Hitoshi; Sekita, Yoko; Huang, Xiaoqiu; Stark, Alexander; Kheradpour, Pouya; Kellis, Manolis; Flicek, Paul; Chen, Yuan; Webber, Caleb; Hardison, Ross; Nelson, Joanne; Hallsworth-Pepin, Kym; Delehaunty, Kim; Markovic, Chris; Minx, Pat; Feng, Yucheng; Kremitzki, Colin; Mitreva, Makedonka; Glasscock, Jarret; Wylie, Todd; Wohldmann, Patricia; Thiru, Prathapan; Nhan, Michael N; Pohl, Craig S; Smith, Scott M; Hou, Shunfeng; Nefedov, Mikhail; de Jong, Pieter J; Renfree, Marilyn B; Mardis, Elaine R; Wilson, Richard K

    2008-05-08

    We present a draft genome sequence of the platypus, Ornithorhynchus anatinus. This monotreme exhibits a fascinating combination of reptilian and mammalian characters. For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles. Analysis of the first monotreme genome aligned these features with genetic innovations. We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology. Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified. Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation.

  20. Genome analysis of the platypus reveals unique signatures of evolution

    Science.gov (United States)

    Warren, Wesley C.; Hillier, LaDeana W.; Marshall Graves, Jennifer A.; Birney, Ewan; Ponting, Chris P.; Grützner, Frank; Belov, Katherine; Miller, Webb; Clarke, Laura; Chinwalla, Asif T.; Yang, Shiaw-Pyng; Heger, Andreas; Locke, Devin P.; Miethke, Pat; Waters, Paul D.; Veyrunes, Frédéric; Fulton, Lucinda; Fulton, Bob; Graves, Tina; Wallis, John; Puente, Xose S.; López-Otín, Carlos; Ordóñez, Gonzalo R.; Eichler, Evan E.; Chen, Lin; Cheng, Ze; Deakin, Janine E.; Alsop, Amber; Thompson, Katherine; Kirby, Patrick; Papenfuss, Anthony T.; Wakefield, Matthew J.; Olender, Tsviya; Lancet, Doron; Huttley, Gavin A.; Smit, Arian F. A.; Pask, Andrew; Temple-Smith, Peter; Batzer, Mark A.; Walker, Jerilyn A.; Konkel, Miriam K.; Harris, Robert S.; Whittington, Camilla M.; Wong, Emily S. W.; Gemmell, Neil J.; Buschiazzo, Emmanuel; Vargas Jentzsch, Iris M.; Merkel, Angelika; Schmitz, Juergen; Zemann, Anja; Churakov, Gennady; Kriegs, Jan Ole; Brosius, Juergen; Murchison, Elizabeth P.; Sachidanandam, Ravi; Smith, Carly; Hannon, Gregory J.; Tsend-Ayush, Enkhjargal; McMillan, Daniel; Attenborough, Rosalind; Rens, Willem; Ferguson-Smith, Malcolm; Lefèvre, Christophe M.; Sharp, Julie A.; Nicholas, Kevin R.; Ray, David A.; Kube, Michael; Reinhardt, Richard; Pringle, Thomas H.; Taylor, James; Jones, Russell C.; Nixon, Brett; Dacheux, Jean-Louis; Niwa, Hitoshi; Sekita, Yoko; Huang, Xiaoqiu; Stark, Alexander; Kheradpour, Pouya; Kellis, Manolis; Flicek, Paul; Chen, Yuan; Webber, Caleb; Hardison, Ross; Nelson, Joanne; Hallsworth-Pepin, Kym; Delehaunty, Kim; Markovic, Chris; Minx, Pat; Feng, Yucheng; Kremitzki, Colin; Mitreva, Makedonka; Glasscock, Jarret; Wylie, Todd; Wohldmann, Patricia; Thiru, Prathapan; Nhan, Michael N.; Pohl, Craig S.; Smith, Scott M.; Hou, Shunfeng; Renfree, Marilyn B.; Mardis, Elaine R.; Wilson, Richard K.

    2009-01-01

    We present a draft genome sequence of the platypus, Ornithorhynchus anatinus. This monotreme exhibits a fascinating combination of reptilian and mammalian characters. For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles. Analysis of the first monotreme genome aligned these features with genetic innovations. We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology. Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified. Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation. PMID:18464734

  1. Comparative genomics of Lactobacillus and other LAB

    DEFF Research Database (Denmark)

    Wassenaar, Trudy M.; Lukjancenko, Oksana

    2014-01-01

    The genomes of 66 LABs, belonging to five different genera, were compared for genome size and gene content. The analyzed genomes included 37 Lactobacillus genomes of 17 species, six Lactococcus lactis genomes, four Leuconostoc genomes of three species, six Streptococcus genomes of two species...... that of the others, with the two Streptococcus species having the shortest genomes. The widest distribution in genome content was observed for Lactobacillus. The number of tRNA and rRNA gene copies varied considerably, with exceptional high numbers observed for Lb. delbrueckii, while these numbers were relatively...

  2. Whole-genome resequencing uncovers molecular signatures of natural and sexual selection in wild bighorn sheep.

    Science.gov (United States)

    Kardos, Marty; Luikart, Gordon; Bunch, Rowan; Dewey, Sarah; Edwards, William; McWilliam, Sean; Stephenson, John; Allendorf, Fred W; Hogg, John T; Kijas, James

    2015-11-01

    The identification of genes influencing fitness is central to our understanding of the genetic basis of adaptation and how it shapes phenotypic variation in wild populations. Here, we used whole-genome resequencing of wild Rocky Mountain bighorn sheep (Ovis canadensis) to >50-fold coverage to identify 2.8 million single nucleotide polymorphisms (SNPs) and genomic regions bearing signatures of directional selection (i.e. selective sweeps). A comparison of SNP diversity between the X chromosome and the autosomes indicated that bighorn males had a dramatically reduced long-term effective population size compared to females. This probably reflects a long history of intense sexual selection mediated by male-male competition for mates. Selective sweep scans based on heterozygosity and nucleotide diversity revealed evidence for a selective sweep shared across multiple populations at RXFP2, a gene that strongly affects horn size in domestic ungulates. The massive horns carried by bighorn rams appear to have evolved in part via strong positive selection at RXFP2. We identified evidence for selection within individual populations at genes affecting early body growth and cellular response to hypoxia; however, these must be interpreted more cautiously as genetic drift is strong within local populations and may have caused false positives. These results represent a rare example of strong genomic signatures of selection identified at genes with known function in wild populations of a nonmodel species. Our results also showcase the value of reference genome assemblies from agricultural or model species for studies of the genomic basis of adaptation in closely related wild taxa. © 2015 John Wiley & Sons Ltd.

  3. The reduced genomes of Parcubacteria (OD1) contain signatures of a symbiotic lifestyle

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, William C.; Stegen, James C.

    2015-07-21

    Candidate phylum OD1 bacteria (also referred to as Parcubacteria) have been identified in broad range of anoxic environments through community survey analysis. Although none of these species have been isolated in the laboratory, several genome sequences have been reconstructed from metagenomic sequence data and single-cell sequencing. The organisms have small (generally <1 Mb) genomes with severely reduced metabolic capabilities. We have reconstructed 8 partial to near-complete OD1 genomes from oxic groundwater samples, and compared them against existing genomic data. The conserved core gene set comprises 202 genes, or ~28% of the genomic complement. ‘Housekeeping’ genes and genes for biosynthesis of peptidoglycan and Type IV pilus production are conserved. Gene sets for biosynthesis of cofactors, amino acids, nucleotides and fatty acids are absent entirely or greatly reduced. The only aspects of energy metabolism conserved are the non-oxidative branch of the pentose-phosphate shunt and central glycolysis. These organisms also lack some activities conserved in almost all other known bacterial genomes, including signal recognition particle, pseudouridine synthase A, and FAD synthase. Pan-genome analysis indicates a broad genotypic diversity and perhaps a highly fluid gene complement, indicating historical adaptation to a wide range of growth environments and a high degree of specialization. The genomes were examined for signatures suggesting either a free-living, streamlined lifestyle or a symbiotic lifestyle. The lack of biosynthetic capabilities and DNA repair, along with the presence of potential attachment and adhesion proteins suggest the Parcubacteria are ectosymbionts or parasites of other organisms. The wide diversity of genes that potentially mediate cell-cell contact suggests a broad range of partner/prey organisms across the phylum.

  4. A genomic copy number signature predicts radiation exposure in post-Chernobyl breast cancer.

    Science.gov (United States)

    Wilke, Christina M; Braselmann, Herbert; Hess, Julia; Klymenko, Sergiy V; Chumak, Vadim V; Zakhartseva, Liubov M; Bakhanova, Elena V; Walch, Axel K; Selmansberger, Martin; Samaga, Daniel; Weber, Peter; Schneider, Ludmila; Fend, Falko; Bösmüller, Hans C; Zitzelsberger, Horst; Unger, Kristian

    2018-04-16

    Breast cancer is the second leading cause of cancer death among women worldwide and besides life-style, age and genetic risk factors, exposure to ionising radiation is known to increase the risk for breast cancer. Further, DNA copy number alterations (CNAs), which can result from radiation-induced double-strand breaks, are frequently occurring in breast cancer cells. We set out to identify a signature of CNAs discriminating breast cancers from radiation-exposed and non-exposed female patients. We analysed resected breast cancer tissues from 68 exposed female Chernobyl clean-up workers and evacuees and 68 matched non-exposed control patients for CNAs by array comparative genomic hybridisation analysis (aCGH). Using a stepwise forward-backward selection approach a non-complex CNA-signature, i.e. less than ten features, was identified in the training data set, which could be subsequently validated in the validation data set (p-value<0.05). The signature consisted of nine copy number regions located on chromosomal bands 7q11.22-11.23, 7q21.3, 16q24.3, 17q21.31, 20p11.23-11.21, 1p21.1, 2q35, 2q35, 6p22.2. The signature was independent of any clinical characteristics of the patients. In all, we identified a CNA-signature that has the potential to allow identification of radiation-associated breast cancer at the individual level. This article is protected by copyright. All rights reserved. © 2018 UICC.

  5. Detecting signatures of selection within the Tibetan sheep mitochondrial genome.

    Science.gov (United States)

    Niu, Lili; Chen, Xiaoyong; Xiao, Ping; Zhao, Qianjun; Zhou, Jingxuan; Hu, Jiangtao; Sun, Hongxin; Guo, Jiazhong; Li, Li; Wang, Linjie; Zhang, Hongping; Zhong, Tao

    2017-11-01

    Tibetan sheep, a Chinese indigenous breed, are mainly distributed in plateau and mountain-valley areas at a terrestrial elevation between 2260 and 4100 m. The herd is genetically distinct from the other domestic sheep and undergoes acclimatization to adapt to the hypoxic environment. To date, whether the mitochondrial DNA modification of Tibetan sheep shares the same feature as the other domestic breed remains unknown. In this study, we compared the whole mitogenome sequences from 32 Tibetan sheep, 22 domestic sheep and 24 commercial sheep to identify the selection signatures of hypoxic-tolerant in Tibetan sheep. Nucleotide diversity analysis using the sliding window method showed that the highest level of nucleotide diversity was observed in the control region with a peak value of π = 0.05215, while the lowest π value was detected in the tRNAs region. qPCR results showed that the relative mtDNA copy number in Tibetan sheep was significantly lower than that in Suffolk sheep. None of the mutations in 12S rRNA were fixed in Tibetan sheep, which indicated that there has been less artificial selection in this herd than the other domestic and commercial breeds. Although one site (1277G) might undergo the purifying selection, it was not identified as the breed-specific allele in Tibetan sheep. We proposed that nature selection was the main drive during the domestication of Tibetan sheep and single mutation (or locus) could not reveal the signature of selection as for the high diversity in the mitogenome of Tibetan sheep.

  6. Evaluation of Signature Erosion in Ebola Virus Due to Genomic Drift and Its Impact on the Performance of Diagnostic Assays

    Science.gov (United States)

    Sozhamannan, Shanmuga; Holland, Mitchell Y.; Hall, Adrienne T.; Negrón, Daniel A.; Ivancich, Mychal; Koehler, Jeffrey W.; Minogue, Timothy D.; Campbell, Catherine E.; Berger, Walter J.; Christopher, George W.; Goodwin, Bruce G.; Smith, Michael A.

    2015-01-01

    Genome sequence analyses of the 2014 Ebola Virus (EBOV) isolates revealed a potential problem with the diagnostic assays currently in use; i.e., drifting genomic profiles of the virus may affect the sensitivity or even produce false-negative results. We evaluated signature erosion in ebolavirus molecular assays using an in silico approach and found frequent potential false-negative and false-positive results. We further empirically evaluated many EBOV assays, under real time PCR conditions using EBOV Kikwit (1995) and Makona (2014) RNA templates. These results revealed differences in performance between assays but were comparable between the old and new EBOV templates. Using a whole genome approach and a novel algorithm, termed BioVelocity, we identified new signatures that are unique to each of EBOV, Sudan virus (SUDV), and Reston virus (RESTV). Interestingly, many of the current assay signatures do not fall within these regions, indicating a potential drawback in the past assay design strategies. The new signatures identified in this study may be evaluated with real-time reverse transcription PCR (rRT-PCR) assay development and validation. In addition, we discuss regulatory implications and timely availability to impact a rapidly evolving outbreak using existing but perhaps less than optimal assays versus redesign these assays for addressing genomic changes. PMID:26090727

  7. Analysis of dinucleotide signatures in HIV-1 subtype B genomes

    Indian Academy of Sciences (India)

    a useful tool to visualize the genome composition and sig- natures of nucleotide sequences, where patterns .... K03455) were obtained using the gene cutter tool. (www.hiv.lanl.gov.in). Chaos game .... (b) RC1 control of the HXB2 genome, (c) SIVCPZ genome and (d) HTLV-1 genome. 406. Journal of Genetics, Vol. 92, No.

  8. Discovery and annotation of functional chromatin signatures in the human genome.

    Directory of Open Access Journals (Sweden)

    Gary Hon

    2009-11-01

    Full Text Available Transcriptional regulation in human cells is a complex process involving a multitude of regulatory elements encoded by the genome. Recent studies have shown that distinct chromatin signatures mark a variety of functional genomic elements and that subtle variations of these signatures mark elements with different functions. To identify novel chromatin signatures in the human genome, we apply a de novo pattern-finding algorithm to genome-wide maps of histone modifications. We recover previously known chromatin signatures associated with promoters and enhancers. We also observe several chromatin signatures with strong enrichment of H3K36me3 marking exons. Closer examination reveals that H3K36me3 is found on well-positioned nucleosomes at exon 5' ends, and that this modification is a global mark of exon expression that also correlates with alternative splicing. Additionally, we observe strong enrichment of H2BK5me1 and H4K20me1 at highly expressed exons near the 5' end, in contrast to the opposite distribution of H3K36me3-marked exons. Finally, we also recover frequently occurring chromatin signatures displaying enrichment of repressive histone modifications. These signatures mark distinct repeat sequences and are associated with distinct modes of gene repression. Together, these results highlight the rich information embedded in the human epigenome and underscore its value in studying gene regulation.

  9. Using the transcriptome to annotate the genome revisited: application of massively parallel signature sequencing (MPSS).

    Science.gov (United States)

    Shah, Trushar; de Villiers, Etienne; Nene, Vishvanath; Hass, Brian; Taracha, Evans; Gardner, Malcolm J; Sansom, Clare; Pelle, Roger; Bishop, Richard

    2006-01-17

    Transcriptome analysis can provide useful data for refining genome sequence annotation. Application of massively parallel signature sequencing (MPSS) revealed reproducible transcription, in multiple MPSS cycles, from 73% of computationally predicted genes in the Theileria parva schizont lifecycle stage. Signatures spanning consecutive exons confirmed 142 predicted introns. MPSS identified 83 putative genes, >100 codons overlooked by annotation software, and 139 potentially incorrect gene models (with either truncated ORFs or overlooked exons) by interfacing signature locations with stop codon maps. Twenty representative models were confirmed as likely to be incorrect using reverse transcription PCR amplification from independent schizont cDNA preparations. More than 50% of the 60 putative single copy genes in T. parva that were absent from the genome of the closely related T. annulata had MPSS signatures. This study illustrates the utility of MPSS for improving annotation of small, gene-rich microbial eukaryotic genomes.

  10. The tiger genome and comparative analysis with lion and snow leopard genomes

    Science.gov (United States)

    Cho, Yun Sung; Hu, Li; Hou, Haolong; Lee, Hang; Xu, Jiaohui; Kwon, Soowhan; Oh, Sukhun; Kim, Hak-Min; Jho, Sungwoong; Kim, Sangsoo; Shin, Young-Ah; Kim, Byung Chul; Kim, Hyunmin; Kim, Chang-uk; Luo, Shu-Jin; Johnson, Warren E.; Koepfli, Klaus-Peter; Schmidt-Küntzel, Anne; Turner, Jason A.; Marker, Laurie; Harper, Cindy; Miller, Susan M.; Jacobs, Wilhelm; Bertola, Laura D.; Kim, Tae Hyung; Lee, Sunghoon; Zhou, Qian; Jung, Hyun-Ju; Xu, Xiao; Gadhvi, Priyvrat; Xu, Pengwei; Xiong, Yingqi; Luo, Yadan; Pan, Shengkai; Gou, Caiyun; Chu, Xiuhui; Zhang, Jilin; Liu, Sanyang; He, Jing; Chen, Ying; Yang, Linfeng; Yang, Yulan; He, Jiaju; Liu, Sha; Wang, Junyi; Kim, Chul Hong; Kwak, Hwanjong; Kim, Jong-Soo; Hwang, Seungwoo; Ko, Junsu; Kim, Chang-Bae; Kim, Sangtae; Bayarlkhagva, Damdin; Paek, Woon Kee; Kim, Seong-Jin; O’Brien, Stephen J.; Wang, Jun; Bhak, Jong

    2013-01-01

    Tigers and their close relatives (Panthera) are some of the world’s most endangered species. Here we report the de novo assembly of an Amur tiger whole-genome sequence as well as the genomic sequences of a white Bengal tiger, African lion, white African lion and snow leopard. Through comparative genetic analyses of these genomes, we find genetic signatures that may reflect molecular adaptations consistent with the big cats’ hypercarnivorous diet and muscle strength. We report a snow leopard-specific genetic determinant in EGLN1 (Met39>Lys39), which is likely to be associated with adaptation to high altitude. We also detect a TYR260G>A mutation likely responsible for the white lion coat colour. Tiger and cat genomes show similar repeat composition and an appreciably conserved synteny. Genomic data from the five big cats provide an invaluable resource for resolving easily identifiable phenotypes evident in very close, but distinct, species. PMID:24045858

  11. The tiger genome and comparative analysis with lion and snow leopard genomes.

    Science.gov (United States)

    Cho, Yun Sung; Hu, Li; Hou, Haolong; Lee, Hang; Xu, Jiaohui; Kwon, Soowhan; Oh, Sukhun; Kim, Hak-Min; Jho, Sungwoong; Kim, Sangsoo; Shin, Young-Ah; Kim, Byung Chul; Kim, Hyunmin; Kim, Chang-Uk; Luo, Shu-Jin; Johnson, Warren E; Koepfli, Klaus-Peter; Schmidt-Küntzel, Anne; Turner, Jason A; Marker, Laurie; Harper, Cindy; Miller, Susan M; Jacobs, Wilhelm; Bertola, Laura D; Kim, Tae Hyung; Lee, Sunghoon; Zhou, Qian; Jung, Hyun-Ju; Xu, Xiao; Gadhvi, Priyvrat; Xu, Pengwei; Xiong, Yingqi; Luo, Yadan; Pan, Shengkai; Gou, Caiyun; Chu, Xiuhui; Zhang, Jilin; Liu, Sanyang; He, Jing; Chen, Ying; Yang, Linfeng; Yang, Yulan; He, Jiaju; Liu, Sha; Wang, Junyi; Kim, Chul Hong; Kwak, Hwanjong; Kim, Jong-Soo; Hwang, Seungwoo; Ko, Junsu; Kim, Chang-Bae; Kim, Sangtae; Bayarlkhagva, Damdin; Paek, Woon Kee; Kim, Seong-Jin; O'Brien, Stephen J; Wang, Jun; Bhak, Jong

    2013-01-01

    Tigers and their close relatives (Panthera) are some of the world's most endangered species. Here we report the de novo assembly of an Amur tiger whole-genome sequence as well as the genomic sequences of a white Bengal tiger, African lion, white African lion and snow leopard. Through comparative genetic analyses of these genomes, we find genetic signatures that may reflect molecular adaptations consistent with the big cats' hypercarnivorous diet and muscle strength. We report a snow leopard-specific genetic determinant in EGLN1 (Met39>Lys39), which is likely to be associated with adaptation to high altitude. We also detect a TYR260G>A mutation likely responsible for the white lion coat colour. Tiger and cat genomes show similar repeat composition and an appreciably conserved synteny. Genomic data from the five big cats provide an invaluable resource for resolving easily identifiable phenotypes evident in very close, but distinct, species.

  12. Signatures of positive selection in East African Shorthorn Zebu: a genome-wide SNP analysis

    Science.gov (United States)

    The small East African Shorthorn Zebu is the main indigenous cattle across East Africa. A recent genome wide SNPs analysis has revealed their ancient stable African taurine x Asian zebu admixture. Here, we assess the presence of candidate signature of positive selection in their genome, with the aim...

  13. Gramene database: navigating plant comparative genomics resources

    Science.gov (United States)

    Gramene (http://www.gramene.org) is an online, open source, curated resource for plant comparative genomics and pathway analysis designed to support researchers working in plant genomics, breeding, evolutionary biology, system biology, and metabolic engineering. It exploits phylogenetic relationship...

  14. Rapid phylogenetic and functional classification of short genomic fragments with signature peptides

    Directory of Open Access Journals (Sweden)

    Berendzen Joel

    2012-08-01

    Full Text Available Abstract Background Classification is difficult for shotgun metagenomics data from environments such as soils, where the diversity of sequences is high and where reference sequences from close relatives may not exist. Approaches based on sequence-similarity scores must deal with the confounding effects that inheritance and functional pressures exert on the relation between scores and phylogenetic distance, while approaches based on sequence alignment and tree-building are typically limited to a small fraction of gene families. We describe an approach based on finding one or more exact matches between a read and a precomputed set of peptide 10-mers. Results At even the largest phylogenetic distances, thousands of 10-mer peptide exact matches can be found between pairs of bacterial genomes. Genes that share one or more peptide 10-mers typically have high reciprocal BLAST scores. Among a set of 403 representative bacterial genomes, some 20 million 10-mer peptides were found to be shared. We assign each of these peptides as a signature of a particular node in a phylogenetic reference tree based on the RNA polymerase genes. We classify the phylogeny of a genomic fragment (e.g., read at the most specific node on the reference tree that is consistent with the phylogeny of observed signature peptides it contains. Using both synthetic data from four newly-sequenced soil-bacterium genomes and ten real soil metagenomics data sets, we demonstrate a sensitivity and specificity comparable to that of the MEGAN metagenomics analysis package using BLASTX against the NR database. Phylogenetic and functional similarity metrics applied to real metagenomics data indicates a signal-to-noise ratio of approximately 400 for distinguishing among environments. Our method assigns ~6.6 Gbp/hr on a single CPU, compared with 25 kbp/hr for methods based on BLASTX against the NR database. Conclusions Classification by exact matching against a precomputed list of signature

  15. Detecting signatures of positive selection associated with musical aptitude in the human genome.

    Science.gov (United States)

    Liu, Xuanyao; Kanduri, Chakravarthi; Oikkonen, Jaana; Karma, Kai; Raijas, Pirre; Ukkola-Vuoti, Liisa; Teo, Yik-Ying; Järvelä, Irma

    2016-02-16

    Abilities related to musical aptitude appear to have a long history in human evolution. To elucidate the molecular and evolutionary background of musical aptitude, we compared genome-wide genotyping data (641 K SNPs) of 148 Finnish individuals characterized for musical aptitude. We assigned signatures of positive selection in a case-control setting using three selection methods: haploPS, XP-EHH and FST. Gene ontology classification revealed that the positive selection regions contained genes affecting inner-ear development. Additionally, literature survey has shown that several of the identified genes were known to be involved in auditory perception (e.g. GPR98, USH2A), cognition and memory (e.g. GRIN2B, IL1A, IL1B, RAPGEF5), reward mechanisms (RGS9), and song perception and production of songbirds (e.g. FOXP1, RGS9, GPR98, GRIN2B). Interestingly, genes related to inner-ear development and cognition were also detected in a previous genome-wide association study of musical aptitude. However, the candidate genes detected in this study were not reported earlier in studies of musical abilities. Identification of genes related to language development (FOXP1 and VLDLR) support the popular hypothesis that music and language share a common genetic and evolutionary background. The findings are consistent with the evolutionary conservation of genes related to auditory processes in other species and provide first empirical evidence for signatures of positive selection for abilities that contribute to musical aptitude.

  16. Detecting signatures of positive selection associated with musical aptitude in the human genome

    Science.gov (United States)

    Liu, Xuanyao; Kanduri, Chakravarthi; Oikkonen, Jaana; Karma, Kai; Raijas, Pirre; Ukkola-Vuoti, Liisa; Teo, Yik-Ying; Järvelä, Irma

    2016-01-01

    Abilities related to musical aptitude appear to have a long history in human evolution. To elucidate the molecular and evolutionary background of musical aptitude, we compared genome-wide genotyping data (641 K SNPs) of 148 Finnish individuals characterized for musical aptitude. We assigned signatures of positive selection in a case-control setting using three selection methods: haploPS, XP-EHH and FST. Gene ontology classification revealed that the positive selection regions contained genes affecting inner-ear development. Additionally, literature survey has shown that several of the identified genes were known to be involved in auditory perception (e.g. GPR98, USH2A), cognition and memory (e.g. GRIN2B, IL1A, IL1B, RAPGEF5), reward mechanisms (RGS9), and song perception and production of songbirds (e.g. FOXP1, RGS9, GPR98, GRIN2B). Interestingly, genes related to inner-ear development and cognition were also detected in a previous genome-wide association study of musical aptitude. However, the candidate genes detected in this study were not reported earlier in studies of musical abilities. Identification of genes related to language development (FOXP1 and VLDLR) support the popular hypothesis that music and language share a common genetic and evolutionary background. The findings are consistent with the evolutionary conservation of genes related to auditory processes in other species and provide first empirical evidence for signatures of positive selection for abilities that contribute to musical aptitude. PMID:26879527

  17. The use of genomic signature distance between bacteriophages and their hosts displays evolutionary relationships and phage growth cycle determination.

    Science.gov (United States)

    Deschavanne, Patrick; DuBow, Michael S; Regeard, Christophe

    2010-07-17

    Bacteriophage classification is mainly based on morphological traits and genome characteristics combined with host information and in some cases on phage growth lifestyle. A lack of molecular tools can impede more precise studies on phylogenetic relationships or even a taxonomic classification. The use of methods to analyze genome sequences without the requirement for homology has allowed advances in classification. Here, we proposed to use genome sequence signature to characterize bacteriophages and to compare them to their host genome signature in order to obtain host-phage relationships and information on their lifestyle. We analyze the host-phage relationships in the four most representative groups of Caudoviridae, the dsDNA group of phages. We demonstrate that the use of phage genomic signature and its comparison with that of the host allows a grouping of phages and is also able to predict the host-phage relationships (lytic vs. temperate). We can thus condense, in relatively simple figures, this phage information dispersed over many publications.

  18. Discovery of functional elements in 12 Drosophila genomes using evolutionary signatures

    Science.gov (United States)

    Stark, Alexander; Lin, Michael F.; Kheradpour, Pouya; Pedersen, Jakob S.; Parts, Leopold; Carlson, Joseph W.; Crosby, Madeline A.; Rasmussen, Matthew D.; Roy, Sushmita; Deoras, Ameya N.; Ruby, J. Graham; Brennecke, Julius; Hodges, Emily; Hinrichs, Angie S.; Caspi, Anat; Paten, Benedict; Park, Seung-Won; Han, Mira V.; Maeder, Morgan L.; Polansky, Benjamin J.; Robson, Bryanne E.; Aerts, Stein; van Helden, Jacques; Hassan, Bassem; Gilbert, Donald G.; Eastman, Deborah A.; Rice, Michael; Weir, Michael; Hahn, Matthew W.; Park, Yongkyu; Dewey, Colin N.; Pachter, Lior; Kent, W. James; Haussler, David; Lai, Eric C.; Bartel, David P.; Hannon, Gregory J.; Kaufman, Thomas C.; Eisen, Michael B.; Clark, Andrew G.; Smith, Douglas; Celniker, Susan E.; Gelbart, William M.; Kellis, Manolis

    2008-01-01

    Sequencing of multiple related species followed by comparative genomics analysis constitutes a powerful approach for the systematic understanding of any genome. Here, we use the genomes of 12 Drosophila species for the de novo discovery of functional elements in the fly. Each type of functional element shows characteristic patterns of change, or ‘evolutionary signatures’, dictated by its precise selective constraints. Such signatures enable recognition of new protein-coding genes and exons, spurious and incorrect gene annotations, and numerous unusual gene structures, including abundant stop-codon readthrough. Similarly, we predict non-protein-coding RNA genes and structures, and new microRNA (miRNA) genes. We provide evidence of miRNA processing and functionality from both hairpin arms and both DNA strands. We identify several classes of pre- and post-transcriptional regulatory motifs, and predict individual motif instances with high confidence. We also study how discovery power scales with the divergence and number of species compared, and we provide general guidelines for comparative studies. PMID:17994088

  19. Cocoa/Cotton Comparative Genomics

    Science.gov (United States)

    With genome sequence from two members of the Malvaceae family recently made available, we are exploring syntenic relationships, gene content, and evolutionary trajectories between the cacao and cotton genomes. An assembly of cacao (Theobroma cacao) using Illumina and 454 sequence technology yielded ...

  20. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium.

    Science.gov (United States)

    Machado, Henrique; Gram, Lone

    2017-01-01

    Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationships using several analyses (16S rRNA, MLSA, fur , amino-acid usage, ANI), which allowed us to identify two misidentified strains. Genome analyses also revealed occurrence of higher and lower GC content clades, correlating with phylogenetic clusters. Pan- and core-genome analysis revealed the conservation of 25% of the genome throughout the genus, with a large and open pan-genome. The major source of genomic diversity could be traced to the smaller chromosome and plasmids. Several of the physiological traits studied in the genus did not correlate with phylogenetic data. Since horizontal gene transfer (HGT) is often suggested as a source of genetic diversity and a potential driver of genomic evolution in bacterial species, we looked into evidence of such in Photobacterium genomes. Genomic islands were the source of genomic differences between strains of the same species. Also, we found transposase genes and CRISPR arrays that suggest multiple encounters with foreign DNA. Presence of genomic exchange traits was widespread and abundant in the genus, suggesting a role in genomic evolution. The high genetic variability and indications of genetic exchange make it difficult to elucidate genome evolutionary paths and raise the awareness of the roles of foreign DNA in the genomic evolution of environmental organisms.

  1. European Chlamydia abortus livestock isolate genomes reveal unusual stability and limited diversity, reflected in geographical signatures.

    Science.gov (United States)

    Seth-Smith, H M B; Busó, Leonor Sánchez; Livingstone, M; Sait, M; Harris, S R; Aitchison, K D; Vretou, Evangelia; Siarkou, V I; Laroucau, K; Sachse, K; Longbottom, D; Thomson, N R

    2017-05-04

    Chlamydia abortus (formerly Chlamydophila abortus) is an economically important livestock pathogen, causing ovine enzootic abortion (OEA), and can also cause zoonotic infections in humans affecting pregnancy outcome. Large-scale genomic studies on other chlamydial species are giving insights into the biology of these organisms but have not yet been performed on C. abortus. Our aim was to investigate a broad collection of European isolates of C. abortus, using next generation sequencing methods, looking at diversity, geographic distribution and genome dynamics. Whole genome sequencing was performed on our collection of 57 C. abortus isolates originating primarily from the UK, Germany, France and Greece, but also from Tunisia, Namibia and the USA. Phylogenetic analysis of a total of 64 genomes shows a deep structural division within the C. abortus species with a major clade displaying limited diversity, in addition to a branch carrying two more distantly related Greek isolates, LLG and POS. Within the major clade, seven further phylogenetic groups can be identified, demonstrating geographical associations. The number of variable nucleotide positions across the sampled isolates is significantly lower than those published for C. trachomatis and C. psittaci. No recombination was identified within C. abortus, and no plasmid was found. Analysis of pseudogenes showed lineage specific loss of some functions, notably with several Pmp and TMH/Inc proteins predicted to be inactivated in many of the isolates studied. The diversity within C. abortus appears to be much lower compared to other species within the genus. There are strong geographical signatures within the phylogeny, indicating clonal expansion within areas of limited livestock transport. No recombination has been identified within this species, showing that different species of Chlamydia may demonstrate different evolutionary dynamics, and that the genome of C. abortus is highly stable.

  2. [HPV-associated head and neck cancer : mutational signature and genomic aberrations].

    Science.gov (United States)

    Wagner, S; Würdemann, N; Hübbers, C; Reuschenbach, M; Prigge, E-S; Wichmann, G; Hess, J; Dietz, A; Dürst, M; Tinhofer, I; von Knebel-Döberitz, M; Wittekindt, C; Klussmann, J P

    2015-11-01

    A significantly increasing proportion of oropharyngeal head and neck carcinomas (OSCC) in North America and Europe are associated with human papillomavirus (HPV) infections. HPV-related OSCC is regarded as a distinct tumor type with regard to its cellular, biologic, and clinical characteristics. Patients with HPV-related OSCC have significantly better local control, but higher rates of regional lymph node and distant metastases as compared to patients with HPV-negative OSCC. Classical molecular genetic investigations demonstrated specific chromosomal aberration signatures in HPV-related OSCC, and recent developments in next generation sequencing (NGS) technology have rendered possible the sequencing of entire genomes, and thus detection of specific mutations, in just a few days. Initial data from The Cancer Genome Atlas (TCGA) project obtained by using genome-wide high throughput methods have confirmed that HPV-related OSCC contain fewer, albeit more specific mutations than HPV-negative tumors. Additionally, these data revealed the presence of specific-potentially therapeutically targetable-activating driver mutations in subgroups of HPV-positive OSCC, some of which have a prognostic impact. Specific targeted NGS technologies provide new possibilities for identification of diagnostic, prognostic, and predictive biomarkers and the development of personalized cancer treatment. Patients with HPV-positive tumors are likely to profit from these developments in the future, since the genetic alterations are relatively homogenous and frequently lead to signal pathway activation. There is an urgent need for network research activities to carry out the necessary basic research in prospective cohort studies.

  3. Whole genome detection of signature of positive selection in African cattle reveals selection for thermotolerance.

    Science.gov (United States)

    Taye, Mengistie; Lee, Wonseok; Caetano-Anolles, Kelsey; Dessie, Tadelle; Hanotte, Olivier; Mwai, Okeyo Ally; Kemp, Stephen; Cho, Seoae; Oh, Sung Jong; Lee, Hak-Kyo; Kim, Heebal

    2017-12-01

    As African indigenous cattle evolved in a hot tropical climate, they have developed an inherent thermotolerance; survival mechanisms include a light-colored and shiny coat, increased sweating, and cellular and molecular mechanisms to cope with high environmental temperature. Here, we report the positive selection signature of genes in African cattle breeds which contribute for their heat tolerance mechanisms. We compared the genomes of five indigenous African cattle breeds with the genomes of four commercial cattle breeds using cross-population composite likelihood ratio (XP-CLR) and cross-population extended haplotype homozygosity (XP-EHH) statistical methods. We identified 296 (XP-EHH) and 327 (XP-CLR) positively selected genes. Gene ontology analysis resulted in 41 biological process terms and six Kyoto Encyclopedia of Genes and Genomes pathways. Several genes and pathways were found to be involved in oxidative stress response, osmotic stress response, heat shock response, hair and skin properties, sweat gland development and sweating, feed intake and metabolism, and reproduction functions. The genes and pathways identified directly or indirectly contribute to the superior heat tolerance mechanisms in African cattle populations. The result will improve our understanding of the biological mechanisms of heat tolerance in African cattle breeds and opens an avenue for further study. © 2017 Japanese Society of Animal Science.

  4. Comparative genomics of Coniophora olivacea reveals different patterns of genome expansion in Boletales.

    Science.gov (United States)

    Castanera, Raúl; Pérez, Gúmer; López-Varas, Leticia; Amselem, Joëlle; LaButti, Kurt; Singan, Vasanth; Lipzen, Anna; Haridas, Sajeet; Barry, Kerrie; Grigoriev, Igor V; Pisabarro, Antonio G; Ramírez, Lucía

    2017-11-16

    Coniophora olivacea is a basidiomycete fungus belonging to the order Boletales that produces brown-rot decay on dead wood of conifers. The Boletales order comprises a diverse group of species including saprotrophs and ectomycorrhizal fungi that show important differences in genome size. In this study we report the 39.07-megabase (Mb) draft genome assembly and annotation of C. olivacea. A total of 14,928 genes were annotated, including 470 putatively secreted proteins enriched in functions involved in lignocellulose degradation. Using similarity clustering and protein structure prediction we identified a new family of 10 putative lytic polysaccharide monooxygenase genes. This family is conserved in basidiomycota and lacks of previous functional annotation. Further analyses showed that C. olivacea has a low repetitive genome, with 2.91% of repeats and a restrained content of transposable elements (TEs). The annotation of TEs in four related Boletales yielded important differences in repeat content, ranging from 3.94 to 41.17% of the genome size. The distribution of insertion ages of LTR-retrotransposons showed that differential expansions of these repetitive elements have shaped the genome architecture of Boletales over the last 60 million years. Coniophora olivacea has a small, compact genome that shows macrosynteny with Coniophora puteana. The functional annotation revealed the enzymatic signature of a canonical brown-rot. The annotation and comparative genomics of transposable elements uncovered their particular contraction in the Coniophora genera, highlighting their role in the differential genome expansions found in Boletales species.

  5. Comparative Reannotation of 21 Aspergillus Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Salamov, Asaf; Riley, Robert; Kuo, Alan; Grigoriev, Igor

    2013-03-08

    We used comparative gene modeling to reannotate 21 Aspergillus genomes. Initial automatic annotation of individual genomes may contain some errors of different nature, e.g. missing genes, incorrect exon-intron structures, 'chimeras', which fuse 2 or more real genes or alternatively splitting some real genes into 2 or more models. The main premise behind the comparative modeling approach is that for closely related genomes most orthologous families have the same conserved gene structure. The algorithm maps all gene models predicted in each individual Aspergillus genome to the other genomes and, for each locus, selects from potentially many competing models, the one which most closely resembles the orthologous genes from other genomes. This procedure is iterated until no further change in gene models is observed. For Aspergillus genomes we predicted in total 4503 new gene models ( ~;;2percent per genome), supported by comparative analysis, additionally correcting ~;;18percent of old gene models. This resulted in a total of 4065 more genes with annotated PFAM domains (~;;3percent increase per genome). Analysis of a few genomes with EST/transcriptomics data shows that the new annotation sets also have a higher number of EST-supported splice sites at exon-intron boundaries.

  6. Defining the genomic signature of totipotency and pluripotency during early human development.

    Directory of Open Access Journals (Sweden)

    Amparo Galan

    Full Text Available The genetic mechanisms governing human pre-implantation embryo development and the in vitro counterparts, human embryonic stem cells (hESCs, still remain incomplete. Previous global genome studies demonstrated that totipotent blastomeres from day-3 human embryos and pluripotent inner cell masses (ICMs from blastocysts, display unique and differing transcriptomes. Nevertheless, comparative gene expression analysis has revealed that no significant differences exist between hESCs derived from blastomeres versus those obtained from ICMs, suggesting that pluripotent hESCs involve a new developmental progression. To understand early human stages evolution, we developed an undifferentiation network signature (UNS and applied it to a differential gene expression profile between single blastomeres from day-3 embryos, ICMs and hESCs. This allowed us to establish a unique signature composed of highly interconnected genes characteristic of totipotency (61 genes, in vivo pluripotency (20 genes, and in vitro pluripotency (107 genes, and which are also proprietary according to functional analysis. This systems biology approach has led to an improved understanding of the molecular and signaling processes governing human pre-implantation embryo development, as well as enabling us to comprehend how hESCs might adapt to in vitro culture conditions.

  7. Gegenees: fragmented alignment of multiple genomes for determining phylogenomic distances and genetic signatures unique for specified target groups.

    Directory of Open Access Journals (Sweden)

    Joakim Agren

    Full Text Available The rapid development of Next Generation Sequencing technologies leads to the accumulation of huge amounts of sequencing data. The scientific community faces an enormous challenge in how to deal with this explosion. Here we present a software tool, 'Gegenees', that uses a fragmented alignment approach to facilitate the comparative analysis of hundreds of microbial genomes. The genomes are fragmented and compared, all against all, by a multithreaded BLAST control engine. Ready-made alignments can be complemented with new genomes without recalculating the existing data points. Gegenees gives a phylogenomic overview of the genomes and the alignment can then be mined for genomic regions with conservation patterns matching a defined target group and absent from a background group. The genomic regions are given biomarker scores forming a uniqueness signature that can be viewed and explored, graphically and in tabular form. A primer/probe alignment tool is also included for specificity verification of currently used or new primers. We exemplify the use of Gegenees on the Bacillus cereus group, on Foot and Mouth Disease Viruses, and on strains from the 2011 Escherichia coli O104:H4 outbreak. Gegenees contributes towards an increased capacity of fast and efficient data mining as more and more genomes become sequenced.

  8. Signatures of adaptation in the weedy rice genome

    Science.gov (United States)

    Weedy rice is a common problem of by product of domestication that has evolved multiple times from cultivated and wild rice relatives. Here we use whole genome sequences to examine the origin and adaptation of the two major US weedy red rice strains, with a comparison to Chinese weedy red rice. We f...

  9. Comparative Genomics of Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Ussery, David; Davenport, C; Tümmler, B

    2010-01-01

    Eleven completely sequenced Chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. The green sulfur bacteria (GSB) are equipped with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and CO(2) fixation. Whole...... weight of 10(6), and are probably instrumental for the bacteria to generate their own intimate (micro)environment....

  10. Comparative genomics using data mining tools

    Indian Academy of Sciences (India)

    Unknown

    1 | February 2002. Comparative genomics using data mining tools. 17 where L is the length of the concerned protein in amino acids and fi is the average frequency of occurrence of the ith amino acid in the set of proteins that are of high sequence complexity and are predicted to have globular fold within the same genome.

  11. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium

    DEFF Research Database (Denmark)

    Machado, Henrique; Gram, Lone

    2017-01-01

    Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand...... the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationships using several analyses (16S rRNA, MLSA, fur, amino-acid usage, ANI), which allowed us to identify two...

  12. The genomic signatures of Shigella evolution, adaptation and geographical spread.

    Science.gov (United States)

    The, Hao Chung; Thanh, Duy Pham; Holt, Kathryn E; Thomson, Nicholas R; Baker, Stephen

    2016-04-01

    Shigella spp. are some of the key pathogens responsible for the global burden of diarrhoeal disease. These facultative intracellular bacteria belong to the family Enterobacteriaceae, together with other intestinal pathogens, such as Escherichia coli and Salmonella spp. The genus Shigella comprises four different species, each consisting of several serogroups, all of which show phenotypic similarity, including invasive pathogenicity. DNA sequencing suggests that this similarity results from the convergent evolution of different Shigella spp. founders. Here, we review the evolutionary relationships between Shigella spp. and E . coli, and we highlight how the genomic plasticity of these bacteria and their acquisition of a distinctive virulence plasmid have enabled the development of such highly specialized pathogens. Furthermore, we discuss the insights that genotyping and whole-genome sequencing have provided into the phylogenetics and intercontinental spread of Shigella spp.

  13. Comparative sequence analyses of genome and transcriptome ...

    Indian Academy of Sciences (India)

    /fulltext/jbsc/040/05/0891-0907. Keywords. Asian elephant; comparative genomics; gene prediction; transcriptome. Abstract. The Asian elephant Elephas maximus and the African elephant Loxodonta africana that diverged 5-7 million years ...

  14. Comparative assembly hubs: Web-accessible browsers for comparative genomics

    Science.gov (United States)

    Nguyen, Ngan; Hickey, Glenn; Raney, Brian J.; Armstrong, Joel; Clawson, Hiram; Zweig, Ann; Karolchik, Donna; Kent, William James; Haussler, David; Paten, Benedict

    2014-01-01

    Motivation: Researchers now have access to large volumes of genome sequences for comparative analysis, some generated by the plethora of public sequencing projects and, increasingly, from individual efforts. It is not possible, or necessarily desirable, that the public genome browsers attempt to curate all these data. Instead, a wealth of powerful tools is emerging to empower users to create their own visualizations and browsers. Results: We introduce a pipeline to easily generate collections of Web-accessible UCSC Genome Browsers interrelated by an alignment. It is intended to democratize our comparative genomic browser resources, serving the broad and growing community of evolutionary genomicists and facilitating easy public sharing via the Internet. Using the alignment, all annotations and the alignment itself can be efficiently viewed with reference to any genome in the collection, symmetrically. A new, intelligently scaled alignment display makes it simple to view all changes between the genomes at all levels of resolution, from substitutions to complex structural rearrangements, including duplications. To demonstrate this work, we create a comparative assembly hub containing 57 Escherichia coli and 9 Shigella genomes and show examples that highlight their unique biology. Availability and implementation: The source code is available as open source at: https://github.com/glennhickey/progressiveCactus The E.coli and Shigella genome hub is now a public hub listed on the UCSC browser public hubs Web page. Contact: benedict@soe.ucsc.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25138168

  15. A Signature of Genomic Instability Resulting from Deficient Replication Licensing.

    Directory of Open Access Journals (Sweden)

    Steven C Pruitt

    2017-01-01

    Full Text Available Insufficient licensing of DNA replication origins has been shown to result in genome instability, stem cell deficiency, and cancers. However, it is unclear whether the DNA damage resulting from deficient replication licensing occurs generally or if specific sites are preferentially affected. To map locations of ongoing DNA damage in vivo, the DNAs present in red blood cell micronuclei were sequenced. Many micronuclei are the product of DNA breaks that leave acentromeric remnants that failed to segregate during mitosis and should reflect the locations of breaks. To validate the approach we show that micronuclear sequences identify known common fragile sites under conditions that induce breaks at these locations (hydroxyurea. In MCM2 deficient mice a different set of preferred breakage sites is identified that includes the tumor suppressor gene Tcf3, which is known to contribute to T-lymphocytic leukemias that arise in these mice, and the 45S rRNA gene repeats.

  16. Comparative Genome Analysis of Enterobacter cloacae

    Science.gov (United States)

    Liu, Wing-Yee; Wong, Chi-Fat; Chung, Karl Ming-Kar; Jiang, Jing-Wei; Leung, Frederick Chi-Ching

    2013-01-01

    The Enterobacter cloacae species includes an extremely diverse group of bacteria that are associated with plants, soil and humans. Publication of the complete genome sequence of the plant growth-promoting endophytic E. cloacae subsp. cloacae ENHKU01 provided an opportunity to perform the first comparative genome analysis between strains of this dynamic species. Examination of the pan-genome of E. cloacae showed that the conserved core genome retains the general physiological and survival genes of the species, while genomic factors in plasmids and variable regions determine the virulence of the human pathogenic E. cloacae strain; additionally, the diversity of fimbriae contributes to variation in colonization and host determination of different E. cloacae strains. Comparative genome analysis further illustrated that E. cloacae strains possess multiple mechanisms for antagonistic action against other microorganisms, which involve the production of siderophores and various antimicrobial compounds, such as bacteriocins, chitinases and antibiotic resistance proteins. The presence of Type VI secretion systems is expected to provide further fitness advantages for E. cloacae in microbial competition, thus allowing it to survive in different environments. Competition assays were performed to support our observations in genomic analysis, where E. cloacae subsp. cloacae ENHKU01 demonstrated antagonistic activities against a wide range of plant pathogenic fungal and bacterial species. PMID:24069314

  17. Gramene database: Navigating plant comparative genomics resources

    Directory of Open Access Journals (Sweden)

    Parul Gupta

    2016-11-01

    Full Text Available Gramene (http://www.gramene.org is an online, open source, curated resource for plant comparative genomics and pathway analysis designed to support researchers working in plant genomics, breeding, evolutionary biology, system biology, and metabolic engineering. It exploits phylogenetic relationships to enrich the annotation of genomic data and provides tools to perform powerful comparative analyses across a wide spectrum of plant species. It consists of an integrated portal for querying, visualizing and analyzing data for 44 plant reference genomes, genetic variation data sets for 12 species, expression data for 16 species, curated rice pathways and orthology-based pathway projections for 66 plant species including various crops. Here we briefly describe the functions and uses of the Gramene database.

  18. A novel data mining method to identify assay-specific signatures in functional genomic studies

    Directory of Open Access Journals (Sweden)

    Guidarelli Jack W

    2006-08-01

    Full Text Available Abstract Background: The highly dimensional data produced by functional genomic (FG studies makes it difficult to visualize relationships between gene products and experimental conditions (i.e., assays. Although dimensionality reduction methods such as principal component analysis (PCA have been very useful, their application to identify assay-specific signatures has been limited by the lack of appropriate methodologies. This article proposes a new and powerful PCA-based method for the identification of assay-specific gene signatures in FG studies. Results: The proposed method (PM is unique for several reasons. First, it is the only one, to our knowledge, that uses gene contribution, a product of the loading and expression level, to obtain assay signatures. The PM develops and exploits two types of assay-specific contribution plots, which are new to the application of PCA in the FG area. The first type plots the assay-specific gene contribution against the given order of the genes and reveals variations in distribution between assay-specific gene signatures as well as outliers within assay groups indicating the degree of importance of the most dominant genes. The second type plots the contribution of each gene in ascending or descending order against a constantly increasing index. This type of plots reveals assay-specific gene signatures defined by the inflection points in the curve. In addition, sharp regions within the signature define the genes that contribute the most to the signature. We proposed and used the curvature as an appropriate metric to characterize these sharp regions, thus identifying the subset of genes contributing the most to the signature. Finally, the PM uses the full dataset to determine the final gene signature, thus eliminating the chance of gene exclusion by poor screening in earlier steps. The strengths of the PM are demonstrated using a simulation study, and two studies of real DNA microarray data – a study of

  19. Genome-scale mutational signatures of aflatoxin in cells, mice, and human tumors

    Science.gov (United States)

    Huang, Mi Ni; Yu, Willie; Teoh, Wei Wei; Ardin, Maude; Jusakul, Apinya; Ng, Alvin Wei Tian; Boot, Arnoud; Abedi-Ardekani, Behnoush; Villar, Stephanie; Myint, Swe Swe; Othman, Rashidah; Poon, Song Ling; Heguy, Adriana; Olivier, Magali; Hollstein, Monica; Tan, Patrick; Teh, Bin Tean; Sabapathy, Kanaga; Zavadil, Jiri; Rozen, Steven G.

    2017-01-01

    Aflatoxin B1 (AFB1) is a mutagen and IARC (International Agency for Research on Cancer) Group 1 carcinogen that causes hepatocellular carcinoma (HCC). Here, we present the first whole-genome data on the mutational signatures of AFB1 exposure from a total of >40,000 mutations in four experimental systems: two different human cell lines, in liver tumors in wild-type mice, and in mice that carried a hepatitis B surface antigen transgene—this to model the multiplicative effects of aflatoxin exposure and hepatitis B in causing HCC. AFB1 mutational signatures from all four experimental systems were remarkably similar. We integrated the experimental mutational signatures with data from newly sequenced HCCs from Qidong County, China, a region of well-studied aflatoxin exposure. This indicated that COSMIC mutational signature 24, previously hypothesized to stem from aflatoxin exposure, indeed likely represents AFB1 exposure, possibly combined with other exposures. Among published somatic mutation data, we found evidence of AFB1 exposure in 0.7% of HCCs treated in North America, 1% of HCCs from Japan, but 16% of HCCs from Hong Kong. Thus, aflatoxin exposure apparently remains a substantial public health issue in some areas. This aspect of our study exemplifies the promise of future widespread resequencing of tumor genomes in providing new insights into the contribution of mutagenic exposures to cancer incidence. PMID:28739859

  20. Genomic Signatures of Strain Selection and Enhancement in Bacillus atrophaeus var. globigii, a Historical Biowarfare Simulant

    Science.gov (United States)

    2011-03-25

    B_amyloliq – B. amyloliquefaciens ; B_NRRL - Bacillus . spp. NRRL; B_SG-1 – Bacillus spp. SG-1; B_thur – B. thuringiensis strains Al Hakam and var...Genomic Signatures of Strain Selection and Enhancement in Bacillus atrophaeus var. globigii, a Historical Biowarfare Simulant Henry S. Gibbons1...States of America, 11 Excet Inc., Aberdeen Proving Ground, Maryland, United States of America Abstract Background: Despite the decades-long use of Bacillus

  1. Comparative genomic analyses of the Taylorellae.

    Science.gov (United States)

    Hauser, Heidi; Richter, Daniel C; van Tonder, Andries; Clark, Louise; Preston, Andrew

    2012-09-14

    Contagious equine metritis (CEM) is an important venereal disease of horses that is of concern to the thoroughbred industry. Taylorella equigenitalis is a causative agent of CEM but very little is known about it or its close relative Taylorella asinigenitalis. To reveal novel information about Taylorella biology, comparative genomic analyses were undertaken. Whole genome sequencing was performed for the T. equigenitalis type strain, NCTC11184. Draft genome sequences were produced for a second T. equigenitalis strain and for a strain of T. asinigenitalis. These genome sequences were analysed and compared to each other and the recently released genome sequence of T. equigenitalis MCE9. These analyses revealed that T. equigenitalis strains appear to be very similar to each other with relatively little strain-specific DNA content. A number of genes were identified that encode putative toxins and adhesins that are possibly involved in infection. Analysis of T. asinigenitalis revealed that it has a very similar gene repertoire to that of T. equigenitalis but shares surprisingly little DNA sequence identity with it. The generation of genome sequence information greatly increases knowledge of these poorly characterised bacteria and greatly facilitates study of them. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Comparative genomics and transcriptomics of Propionibacterium acnes.

    Science.gov (United States)

    Brzuszkiewicz, Elzbieta; Weiner, January; Wollherr, Antje; Thürmer, Andrea; Hüpeden, Jennifer; Lomholt, Hans B; Kilian, Mogens; Gottschalk, Gerhard; Daniel, Rolf; Mollenkopf, Hans-Joachim; Meyer, Thomas F; Brüggemann, Holger

    2011-01-01

    The anaerobic gram-positive bacterium Propionibacterium acnes is a human skin commensal that is occasionally associated with inflammatory diseases. Recent work has indicated that evolutionary distinct lineages of P. acnes play etiologic roles in disease while others are associated with maintenance of skin homeostasis. To shed light on the molecular basis for differential strain properties, we carried out genomic and transcriptomic analysis of distinct P. acnes strains. We sequenced the genome of the P. acnes strain 266, a type I-1a strain. Comparative genome analysis of strain 266 and four other P. acnes strains revealed that overall genome plasticity is relatively low; however, a number of island-like genomic regions, encoding a variety of putative virulence-associated and fitness traits differ between phylotypes, as judged from PCR analysis of a collection of P. acnes strains. Comparative transcriptome analysis of strains KPA171202 (type I-2) and 266 during exponential growth revealed inter-strain differences in gene expression of transport systems and metabolic pathways. In addition, transcript levels of genes encoding possible virulence factors such as dermatan-sulphate adhesin, polyunsaturated fatty acid isomerase, iron acquisition protein HtaA and lipase GehA were upregulated in strain 266. We investigated differential gene expression during exponential and stationary growth phases. Genes encoding components of the energy-conserving respiratory chain as well as secreted and virulence-associated factors were transcribed during the exponential phase, while the stationary growth phase was characterized by upregulation of genes involved in stress responses and amino acid metabolism. Our data highlight the genomic basis for strain diversity and identify, for the first time, the actively transcribed part of the genome, underlining the important role growth status plays in the inflammation-inducing activity of P. acnes. We argue that the disease-causing potential of

  3. Comparative genomics and transcriptomics of Propionibacterium acnes.

    Directory of Open Access Journals (Sweden)

    Elzbieta Brzuszkiewicz

    Full Text Available The anaerobic gram-positive bacterium Propionibacterium acnes is a human skin commensal that is occasionally associated with inflammatory diseases. Recent work has indicated that evolutionary distinct lineages of P. acnes play etiologic roles in disease while others are associated with maintenance of skin homeostasis. To shed light on the molecular basis for differential strain properties, we carried out genomic and transcriptomic analysis of distinct P. acnes strains. We sequenced the genome of the P. acnes strain 266, a type I-1a strain. Comparative genome analysis of strain 266 and four other P. acnes strains revealed that overall genome plasticity is relatively low; however, a number of island-like genomic regions, encoding a variety of putative virulence-associated and fitness traits differ between phylotypes, as judged from PCR analysis of a collection of P. acnes strains. Comparative transcriptome analysis of strains KPA171202 (type I-2 and 266 during exponential growth revealed inter-strain differences in gene expression of transport systems and metabolic pathways. In addition, transcript levels of genes encoding possible virulence factors such as dermatan-sulphate adhesin, polyunsaturated fatty acid isomerase, iron acquisition protein HtaA and lipase GehA were upregulated in strain 266. We investigated differential gene expression during exponential and stationary growth phases. Genes encoding components of the energy-conserving respiratory chain as well as secreted and virulence-associated factors were transcribed during the exponential phase, while the stationary growth phase was characterized by upregulation of genes involved in stress responses and amino acid metabolism. Our data highlight the genomic basis for strain diversity and identify, for the first time, the actively transcribed part of the genome, underlining the important role growth status plays in the inflammation-inducing activity of P. acnes. We argue that the disease

  4. Sequencing and comparing whole mitochondrial genomes ofanimals

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.; Macey, J. Robert; Medina, Monica

    2005-04-22

    Comparing complete animal mitochondrial genome sequences is becoming increasingly common for phylogenetic reconstruction and as a model for genome evolution. Not only are they much more informative than shorter sequences of individual genes for inferring evolutionary relatedness, but these data also provide sets of genome-level characters, such as the relative arrangements of genes, that can be especially powerful. We describe here the protocols commonly used for physically isolating mtDNA, for amplifying these by PCR or RCA, for cloning,sequencing, assembly, validation, and gene annotation, and for comparing both sequences and gene arrangements. On several topics, we offer general observations based on our experiences to date with determining and comparing complete mtDNA sequences.

  5. VISTA - computational tools for comparative genomics

    Energy Technology Data Exchange (ETDEWEB)

    Frazer, Kelly A.; Pachter, Lior; Poliakov, Alexander; Rubin,Edward M.; Dubchak, Inna

    2004-01-01

    Comparison of DNA sequences from different species is a fundamental method for identifying functional elements in genomes. Here we describe the VISTA family of tools created to assist biologists in carrying out this task. Our first VISTA server at http://www-gsd.lbl.gov/VISTA/ was launched in the summer of 2000 and was designed to align long genomic sequences and visualize these alignments with associated functional annotations. Currently the VISTA site includes multiple comparative genomics tools and provides users with rich capabilities to browse pre-computed whole-genome alignments of large vertebrate genomes and other groups of organisms with VISTA Browser, submit their own sequences of interest to several VISTA servers for various types of comparative analysis, and obtain detailed comparative analysis results for a set of cardiovascular genes. We illustrate capabilities of the VISTA site by the analysis of a 180 kilobase (kb) interval on human chromosome 5 that encodes for the kinesin family member3A (KIF3A) protein.

  6. Genome-wide copy number variation pattern analysis and a classification signature for non-small cell lung cancer.

    Science.gov (United States)

    Qiu, Zhe-Wei; Bi, Jia-Hao; Gazdar, Adi F; Song, Kai

    2017-07-01

    The accurate classification of non-small cell lung carcinoma (NSCLC) into lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) is essential for both clinical practice and lung cancer research. Although the standard WHO diagnosis of NSCLC on biopsy material is rapid and economic, more than 13% of NSCLC tumors in the USA are not further classified. The purpose of this study was to analyze the genome-wide pattern differences in copy number variations (CNVs) and to develop a CNV signature as an adjunct test for the routine histopathologic classification of NSCLCs. We investigated the genome-wide CNV differences between these two tumor types using three independent patient datasets. Approximately half of the genes examined exhibited significant differences between LUAD and LUSC tumors and the corresponding non-malignant tissues. A new classifier was developed to identify signature genes out of 20 000 genes. Thirty-three genes were identified as a CNV signature of NSCLC. Using only their CNV values, the classification model separated the LUADs from the LUSCs with an accuracy of 0.88 and 0.84, respectively, in the training and validation datasets. The same signature also classified NSCLC tumors from their corresponding non-malignant samples with an accuracy of 0.96 and 0.98, respectively. We also compared the CNV patterns of NSCLC tumors with those of histologically similar tumors arising at other sites, such as the breast, head, and neck, and four additional tumors. Of greater importance, the significant differences between these tumors may offer the possibility of identifying the origin of tumors whose origin is unknown. © 2017 Wiley Periodicals, Inc.

  7. Gramene 2013: comparative plant genomics resources.

    Science.gov (United States)

    Monaco, Marcela K; Stein, Joshua; Naithani, Sushma; Wei, Sharon; Dharmawardhana, Palitha; Kumari, Sunita; Amarasinghe, Vindhya; Youens-Clark, Ken; Thomason, James; Preece, Justin; Pasternak, Shiran; Olson, Andrew; Jiao, Yinping; Lu, Zhenyuan; Bolser, Dan; Kerhornou, Arnaud; Staines, Dan; Walts, Brandon; Wu, Guanming; D'Eustachio, Peter; Haw, Robin; Croft, David; Kersey, Paul J; Stein, Lincoln; Jaiswal, Pankaj; Ware, Doreen

    2014-01-01

    Gramene (http://www.gramene.org) is a curated online resource for comparative functional genomics in crops and model plant species, currently hosting 27 fully and 10 partially sequenced reference genomes in its build number 38. Its strength derives from the application of a phylogenetic framework for genome comparison and the use of ontologies to integrate structural and functional annotation data. Whole-genome alignments complemented by phylogenetic gene family trees help infer syntenic and orthologous relationships. Genetic variation data, sequences and genome mappings available for 10 species, including Arabidopsis, rice and maize, help infer putative variant effects on genes and transcripts. The pathways section also hosts 10 species-specific metabolic pathways databases developed in-house or by our collaborators using Pathway Tools software, which facilitates searches for pathway, reaction and metabolite annotations, and allows analyses of user-defined expression datasets. Recently, we released a Plant Reactome portal featuring 133 curated rice pathways. This portal will be expanded for Arabidopsis, maize and other plant species. We continue to provide genetic and QTL maps and marker datasets developed by crop researchers. The project provides a unique community platform to support scientific research in plant genomics including studies in evolution, genetics, plant breeding, molecular biology, biochemistry and systems biology.

  8. Comparative genomics of Shiga toxin encoding bacteriophages

    Directory of Open Access Journals (Sweden)

    Smith Darren L

    2012-07-01

    Full Text Available Abstract Background Stx bacteriophages are responsible for driving the dissemination of Stx toxin genes (stx across their bacterial host range. Lysogens carrying Stx phages can cause severe, life-threatening disease and Stx toxin is an integral virulence factor. The Stx-bacteriophage vB_EcoP-24B, commonly referred to as Ф24B, is capable of multiply infecting a single bacterial host cell at a high frequency, with secondary infection increasing the rate at which subsequent bacteriophage infections can occur. This is biologically unusual, therefore determining the genomic content and context of Ф24B compared to other lambdoid Stx phages is important to understanding the factors controlling this phenomenon and determining whether they occur in other Stx phages. Results The genome of the Stx2 encoding phage, Ф24B was sequenced and annotated. The genomic organisation and general features are similar to other sequenced Stx bacteriophages induced from Enterohaemorrhagic Escherichia coli (EHEC, however Ф24B possesses significant regions of heterogeneity, with implications for phage biology and behaviour. The Ф24B genome was compared to other sequenced Stx phages and the archetypal lambdoid phage, lambda, using the Circos genome comparison tool and a PCR-based multi-loci comparison system. Conclusions The data support the hypothesis that Stx phages are mosaic, and recombination events between the host, phages and their remnants within the same infected bacterial cell will continue to drive the evolution of Stx phage variants and the subsequent dissemination of shigatoxigenic potential.

  9. Comparative insect mitochondrial genomes: Differences despite ...

    African Journals Online (AJOL)

    We present a comparative analysis of select insect mitochondrial DNA (mtDNA) representing four insect orders (Diptera, Hymenoptera, Orthoptera and Coleoptera) consisting of 12 different species in an effort to study a common set of genes and to understand the evolution of mitochondrial genome. A functional analysis of ...

  10. Comparative genomics of biotechnologically important yeasts

    NARCIS (Netherlands)

    Riley, Robert; Haridas, Sajeet; Wolfe, Kenneth H; Lopes, Mariana R; Hittinger, Chris Todd; Göker, Markus; Salamov, Asaf A; Wisecaver, Jennifer H; Long, Tanya M; Calvey, Christopher H; Aerts, Andrea L; Barry, Kerrie W; Choi, Cindy; Clum, Alicia; Coughlan, Aisling Y; Deshpande, Shweta; Douglass, Alexander P; Hanson, Sara J; Klenk, Hans-Peter; LaButti, Kurt M; Lapidus, Alla; Lindquist, Erika A; Lipzen, Anna M; Meier-Kolthoff, Jan P; Ohm, Robin A; Otillar, Robert P; Pangilinan, Jasmyn L; Peng, Yi; Rokas, Antonis; Rosa, Carlos A; Scheuner, Carmen; Sibirny, Andriy A; Slot, Jason C; Stielow, J Benjamin; Sun, Hui; Kurtzman, Cletus P; Blackwell, Meredith; Grigoriev, Igor V; Jeffries, Thomas W

    2016-01-01

    Ascomycete yeasts are metabolically diverse, with great potential for biotechnology. Here, we report the comparative genome analysis of 29 taxonomically and biotechnologically important yeasts, including 16 newly sequenced. We identify a genetic code change, CUG-Ala, in Pachysolen tannophilus in the

  11. Comparative and functional genomics of Listeria spp.

    Science.gov (United States)

    Hain, Torsten; Steinweg, Christiane; Chakraborty, Trinad

    2006-10-20

    The genus Listeria comprises a group of non-sporulating, Gram-positive, soil bacteria belonging to the low G+C group of microorganisms. The genus consists of only six species, L. monocytogenes, L. ivanovii, L. seeligeri, L. innocua, L. welshimeri, and L. grayi.L. monocytogenes and L. ivanovii are the only known pathogens of this group. Comparative whole-genome sequencing of representative strains comprising the entire genus is currently being performed and nearing completion. In the genus Listeria, genome reduction has led to the generation of non-pathogenic species from pathogenic progenitor strains. Indeed, many of the regions absent in the non-pathogenic species represent commonly deleted genes. Speciation and diversity of strains has been achieved by horizontal gene transfer of DNA encoding novel genes probably required for niche specific survival. The sequencing of several listerial genomes has also been accompanied by studies using global strategies involving whole-genome transcriptional profiling and proteomics to examine the adaptative changes of L. monocytogenes to growth in different environments and to catalogue the genes mediating these responses. We review this data and present information on the expression profile of L. monocytogenes EGD-e inside the vacuolar and the cytosolic environments of the host cell using whole-genome microarray analysis. Of the 484 genes regulated during intracellular growth 41 genes are species-specific, being absent from the genome of the non-pathogenic L. innocua CLIP 11262 strain. There were 25 genes that are strain-specific i.e. absent from the genome of the L. monocytogenes F2365 serotype 4b strain suggesting heterogeneity in the gene pool required for intracellular survival of L. monocytogenes in host cells.

  12. Population genomics of the honey bee reveals strong signatures of positive selection on worker traits.

    Science.gov (United States)

    Harpur, Brock A; Kent, Clement F; Molodtsova, Daria; Lebon, Jonathan M D; Alqarni, Abdulaziz S; Owayss, Ayman A; Zayed, Amro

    2014-02-18

    Most theories used to explain the evolution of eusociality rest upon two key assumptions: mutations affecting the phenotype of sterile workers evolve by positive selection if the resulting traits benefit fertile kin, and that worker traits provide the primary mechanism allowing social insects to adapt to their environment. Despite the common view that positive selection drives phenotypic evolution of workers, we know very little about the prevalence of positive selection acting on the genomes of eusocial insects. We mapped the footprints of positive selection in Apis mellifera through analysis of 40 individual genomes, allowing us to identify thousands of genes and regulatory sequences with signatures of adaptive evolution over multiple timescales. We found Apoidea- and Apis-specific genes to be enriched for signatures of positive selection, indicating that novel genes play a disproportionately large role in adaptive evolution of eusocial insects. Worker-biased proteins have higher signatures of adaptive evolution relative to queen-biased proteins, supporting the view that worker traits are key to adaptation. We also found genes regulating worker division of labor to be enriched for signs of positive selection. Finally, genes associated with worker behavior based on analysis of brain gene expression were highly enriched for adaptive protein and cis-regulatory evolution. Our study highlights the significant contribution of worker phenotypes to adaptive evolution in social insects, and provides a wealth of knowledge on the loci that influence fitness in honey bees.

  13. NCI Workshop Report: Clinical and Computational Requirements for Correlating Imaging Phenotypes with Genomics Signatures

    Directory of Open Access Journals (Sweden)

    Rivka Colen

    2014-10-01

    Full Text Available The National Cancer Institute (NCI Cancer Imaging Program organized two related workshops on June 26–27, 2013, entitled “Correlating Imaging Phenotypes with Genomics Signatures Research” and “Scalable Computational Resources as Required for Imaging-Genomics Decision Support Systems.” The first workshop focused on clinical and scientific requirements, exploring our knowledge of phenotypic characteristics of cancer biological properties to determine whether the field is sufficiently advanced to correlate with imaging phenotypes that underpin genomics and clinical outcomes, and exploring new scientific methods to extract phenotypic features from medical images and relate them to genomics analyses. The second workshop focused on computational methods that explore informatics and computational requirements to extract phenotypic features from medical images and relate them to genomics analyses and improve the accessibility and speed of dissemination of existing NIH resources. These workshops linked clinical and scientific requirements of currently known phenotypic and genotypic cancer biology characteristics with imaging phenotypes that underpin genomics and clinical outcomes. The group generated a set of recommendations to NCI leadership and the research community that encourage and support development of the emerging radiogenomics research field to address short-and longer-term goals in cancer research.

  14. Comparative genomics of chondrichthyan Hoxa clusters

    Directory of Open Access Journals (Sweden)

    Zhong Ying-Fu

    2009-09-01

    Full Text Available Abstract Background The chondrichthyan or cartilaginous fish (chimeras, sharks, skates and rays occupy an important phylogenetic position as the sister group to all other jawed vertebrates and as an early lineage to diverge from the vertebrate lineage following two whole genome duplication events in vertebrate evolution. There have been few comparative genomic analyses incorporating data from chondrichthyan fish and none comparing genomic information from within the group. We have sequenced the complete Hoxa cluster of the Little Skate (Leucoraja erinacea and compared to the published Hoxa cluster of the Horn Shark (Heterodontus francisci and to available data from the Elephant Shark (Callorhinchus milii genome project. Results A BAC clone containing the full Little Skate Hoxa cluster was fully sequenced and assembled. Analyses of coding sequences and conserved non-coding elements reveal a strikingly high level of conservation across the cartilaginous fish, with twenty ultraconserved elements (100%,100 bp found between Skate and Horn Shark, compared to three between human and marsupials. We have also identified novel potential non-coding RNAs in the Skate BAC clone, some of which are conserved to other species. Conclusion We find that the Little Skate Hoxa cluster is remarkably similar to the previously published Horn Shark Hoxa cluster with respect to sequence identity, gene size and intergenic distance despite over 180 million years of separation between the two lineages. We suggest that the genomes of cartilaginous fish are more highly conserved than those of tetrapods or teleost fish and so are more likely to have retained ancestral non-coding elements. While useful for isolating homologous DNA, this complicates bioinformatic approaches to identify chondrichthyan-specific non-coding DNA elements

  15. Comparative Genome Analysis of Fusobacterium nucleatum.

    Science.gov (United States)

    Ang, Mia Yang; Dutta, Avirup; Wee, Wei Yee; Dymock, David; Paterson, Ian C; Choo, Siew Woh

    2016-10-05

    Fusobacterium nucleatum is considered to be a key oral bacterium in recruiting periodontal pathogens into subgingival dental plaque. Currently F. nucleatum can be subdivided into five subspecies. Our previous genome analysis of F. nucleatum W1481 (referred to hereafter as W1481), isolated from an 8-mm periodontal pocket in a patient with chronic periodontitis, suggested the possibility of a new subspecies. To further investigate the biology and relationships of this possible subspecies with other known subspecies, we performed comparative analysis between W1481 and 35 genome sequences represented by the five known Fusobacterium subspecies. Our analyses suggest that W1481 is most likely a new F. nucleatum subspecies, supported by evidence from phylogenetic analyses and maximal unique match indices (MUMi). Interestingly, we found a horizontally transferred W1481-specific genomic island harboring the tripartite ATP-independent (TRAP)-like transporter genes, suggesting this bacterium might have a high-affinity transport system for the C4-dicarboxylates malate, succinate, and fumarate. Moreover, we found virulence genes in the W1481 genome that may provide a strong defense mechanism which might enable it to colonize and survive within the host by evading immune surveillance. This comparative study provides better understanding of F. nucleatum and the basis for future functional work on this important pathogen. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. A genome-wide scan for selection signatures in Nellore cattle.

    Science.gov (United States)

    Somavilla, A L; Sonstegard, T S; Higa, R H; Rosa, A N; Siqueira, F; Silva, L O C; Torres Júnior, R A A; Coutinho, L L; Mudadu, M A; Alencar, M M; Regitano, L C A

    2014-12-01

    Brazilian Nellore cattle (Bos indicus) have been selected for growth traits for over more than four decades. In recent years, reproductive and meat quality traits have become more important because of increasing consumption, exports and consumer demand. The identification of genome regions altered by artificial selection can potentially permit a better understanding of the biology of specific phenotypes that are useful for the development of tools designed to increase selection efficiency. Therefore, the aims of this study were to detect evidence of recent selection signatures in Nellore cattle using extended haplotype homozygosity methodology and BovineHD marker genotypes (>777,000 single nucleotide polymorphisms) as well as to identify corresponding genes underlying these signals. Thirty-one significant regions (P meat quality, fatty acid profiles and immunity. In addition, 545 genes were identified in regions harboring selection signatures. Within this group, 58 genes were associated with growth, muscle and adipose tissue metabolism, reproductive traits or the immune system. Using relative extended haplotype homozygosity to analyze high-density single nucleotide polymorphism marker data allowed for the identification of regions potentially under artificial selection pressure in the Nellore genome, which might be used to better understand autozygosity and the effects of selection on the Nellore genome. © 2014 Stichting International Foundation for Animal Genetics.

  17. NSD1 mutations generate a genome-wide DNA methylation signature.

    LENUS (Irish Health Repository)

    Choufani, S

    2015-12-22

    Sotos syndrome (SS) represents an important human model system for the study of epigenetic regulation; it is an overgrowth\\/intellectual disability syndrome caused by mutations in a histone methyltransferase, NSD1. As layered epigenetic modifications are often interdependent, we propose that pathogenic NSD1 mutations have a genome-wide impact on the most stable epigenetic mark, DNA methylation (DNAm). By interrogating DNAm in SS patients, we identify a genome-wide, highly significant NSD1(+\\/-)-specific signature that differentiates pathogenic NSD1 mutations from controls, benign NSD1 variants and the clinically overlapping Weaver syndrome. Validation studies of independent cohorts of SS and controls assigned 100% of these samples correctly. This highly specific and sensitive NSD1(+\\/-) signature encompasses genes that function in cellular morphogenesis and neuronal differentiation, reflecting cardinal features of the SS phenotype. The identification of SS-specific genome-wide DNAm alterations will facilitate both the elucidation of the molecular pathophysiology of SS and the development of improved diagnostic testing.

  18. Genome-wide signatures of population bottlenecks and diversifying selection in European wolves.

    Science.gov (United States)

    Pilot, M; Greco, C; vonHoldt, B M; Jędrzejewska, B; Randi, E; Jędrzejewski, W; Sidorovich, V E; Ostrander, E A; Wayne, R K

    2014-04-01

    Genomic resources developed for domesticated species provide powerful tools for studying the evolutionary history of their wild relatives. Here we use 61K single-nucleotide polymorphisms (SNPs) evenly spaced throughout the canine nuclear genome to analyse evolutionary relationships among the three largest European populations of grey wolves in comparison with other populations worldwide, and investigate genome-wide effects of demographic bottlenecks and signatures of selection. European wolves have a discontinuous range, with large and connected populations in Eastern Europe and relatively smaller, isolated populations in Italy and the Iberian Peninsula. Our results suggest a continuous decline in wolf numbers in Europe since the Late Pleistocene, and long-term isolation and bottlenecks in the Italian and Iberian populations following their divergence from the Eastern European population. The Italian and Iberian populations have low genetic variability and high linkage disequilibrium, but relatively few autozygous segments across the genome. This last characteristic clearly distinguishes them from populations that underwent recent drastic demographic declines or founder events, and implies long-term bottlenecks in these two populations. Although genetic drift due to spatial isolation and bottlenecks seems to be a major evolutionary force diversifying the European populations, we detected 35 loci that are putatively under diversifying selection. Two of these loci flank the canine platelet-derived growth factor gene, which affects bone growth and may influence differences in body size between wolf populations. This study demonstrates the power of population genomics for identifying genetic signals of demographic bottlenecks and detecting signatures of directional selection in bottlenecked populations, despite their low background variability.

  19. Genomic alterations detected by comparative genomic hybridization in ovarian endometriomas

    Directory of Open Access Journals (Sweden)

    L.C. Veiga-Castelli

    2010-08-01

    Full Text Available Endometriosis is a complex and multifactorial disease. Chromosomal imbalance screening in endometriotic tissue can be used to detect hot-spot regions in the search for a possible genetic marker for endometriosis. The objective of the present study was to detect chromosomal imbalances by comparative genomic hybridization (CGH in ectopic tissue samples from ovarian endometriomas and eutopic tissue from the same patients. We evaluated 10 ovarian endometriotic tissues and 10 eutopic endometrial tissues by metaphase CGH. CGH was prepared with normal and test DNA enzymatically digested, ligated to adaptors and amplified by PCR. A second PCR was performed for DNA labeling. Equal amounts of both normal and test-labeled DNA were hybridized in human normal metaphases. The Isis FISH Imaging System V 5.0 software was used for chromosome analysis. In both eutopic and ectopic groups, 4/10 samples presented chromosomal alterations, mainly chromosomal gains. CGH identified 11q12.3-q13.1, 17p11.1-p12, 17q25.3-qter, and 19p as critical regions. Genomic imbalances in 11q, 17p, 17q, and 19p were detected in normal eutopic and/or ectopic endometrium from women with ovarian endometriosis. These regions contain genes such as POLR2G, MXRA7 and UBA52 involved in biological processes that may lead to the establishment and maintenance of endometriotic implants. This genomic imbalance may affect genes in which dysregulation impacts both eutopic and ectopic endometrium.

  20. Comparative genome analysis of Basidiomycete fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert; Salamov, Asaf; Henrissat, Bernard; Nagy, Laszlo; Brown, Daren; Held, Benjamin; Baker, Scott; Blanchette, Robert; Boussau, Bastien; Doty, Sharon L.; Fagnan, Kirsten; Floudas, Dimitris; Levasseur, Anthony; Manning, Gerard; Martin, Francis; Morin, Emmanuelle; Otillar, Robert; Pisabarro, Antonio; Walton, Jonathan; Wolfe, Ken; Hibbett, David; Grigoriev, Igor

    2013-08-07

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprotrophs including the majority of wood decaying and ectomycorrhizal species. To better understand the genetic diversity of this phylum we compared the genomes of 35 basidiomycetes including 6 newly sequenced genomes. These genomes span extremes of genome size, gene number, and repeat content. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) found in only one organism. Correlations between lifestyle and certain gene families are evident. Phylogenetic patterns of plant biomass-degrading genes in Agaricomycotina suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. Based on phylogenetically-informed PCA analysis of wood decay genes, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has typical ligninolytic class II fungal peroxidases (PODs). This prediction is supported by growth assays in which both fungi exhibit wood decay with white rot-like characteristics. Based on this, we suggest that the white/brown rot dichotomy may be inadequate to describe the full range of wood decaying fungi. Analysis of the rate of discovery of proteins with no or few homologs suggests the value of continued sequencing of basidiomycete fungi.

  1. Comparative expression profiling in grape (Vitis vinifera berries derived from frequency analysis of ESTs and MPSS signatures

    Directory of Open Access Journals (Sweden)

    Cook Douglas R

    2008-05-01

    Full Text Available Abstract Background Vitis vinifera (V. vinifera is the primary grape species cultivated for wine production, with an industry valued annually in the billions of dollars worldwide. In order to sustain and increase grape production, it is necessary to understand the genetic makeup of grape species. Here we performed mRNA profiling using Massively Parallel Signature Sequencing (MPSS and combined it with available Expressed Sequence Tag (EST data. These tag-based technologies, which do not require a priori knowledge of genomic sequence, are well-suited for transcriptional profiling. The sequence depth of MPSS allowed us to capture and quantify almost all the transcripts at a specific stage in the development of the grape berry. Results The number and relative abundance of transcripts from stage II grape berries was defined using Massively Parallel Signature Sequencing (MPSS. A total of 2,635,293 17-base and 2,259,286 20-base signatures were obtained, representing at least 30,737 and 26,878 distinct sequences. The average normalized abundance per signature was ~49 TPM (Transcripts Per Million. Comparisons of the MPSS signatures with available Vitis species' ESTs and a unigene set demonstrated that 6,430 distinct contigs and 2,190 singletons have a perfect match to at least one MPSS signature. Among the matched sequences, ESTs were identified from tissues other than berries or from berries at different developmental stages. Additional MPSS signatures not matching to known grape ESTs can extend our knowledge of the V. vinifera transcriptome, particularly when these data are used to assist in annotation of whole genome sequences from Vitis vinifera. Conclusion The MPSS data presented here not only achieved a higher level of saturation than previous EST based analyses, but in doing so, expand the known set of transcripts of grape berries during the unique stage in development that immediately precedes the onset of ripening. The MPSS dataset also revealed

  2. Comparative expression profiling in grape (Vitis vinifera) berries derived from frequency analysis of ESTs and MPSS signatures.

    Science.gov (United States)

    Iandolino, Alberto; Nobuta, Kan; da Silva, Francisco Goes; Cook, Douglas R; Meyers, Blake C

    2008-05-12

    Vitis vinifera (V. vinifera) is the primary grape species cultivated for wine production, with an industry valued annually in the billions of dollars worldwide. In order to sustain and increase grape production, it is necessary to understand the genetic makeup of grape species. Here we performed mRNA profiling using Massively Parallel Signature Sequencing (MPSS) and combined it with available Expressed Sequence Tag (EST) data. These tag-based technologies, which do not require a priori knowledge of genomic sequence, are well-suited for transcriptional profiling. The sequence depth of MPSS allowed us to capture and quantify almost all the transcripts at a specific stage in the development of the grape berry. The number and relative abundance of transcripts from stage II grape berries was defined using Massively Parallel Signature Sequencing (MPSS). A total of 2,635,293 17-base and 2,259,286 20-base signatures were obtained, representing at least 30,737 and 26,878 distinct sequences. The average normalized abundance per signature was approximately 49 TPM (Transcripts Per Million). Comparisons of the MPSS signatures with available Vitis species' ESTs and a unigene set demonstrated that 6,430 distinct contigs and 2,190 singletons have a perfect match to at least one MPSS signature. Among the matched sequences, ESTs were identified from tissues other than berries or from berries at different developmental stages. Additional MPSS signatures not matching to known grape ESTs can extend our knowledge of the V. vinifera transcriptome, particularly when these data are used to assist in annotation of whole genome sequences from Vitis vinifera. The MPSS data presented here not only achieved a higher level of saturation than previous EST based analyses, but in doing so, expand the known set of transcripts of grape berries during the unique stage in development that immediately precedes the onset of ripening. The MPSS dataset also revealed evidence of antisense expression not

  3. Comparative genomics and evolution of eukaryotic phospholipidbiosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Lykidis, Athanasios

    2006-12-01

    Phospholipid biosynthetic enzymes produce diverse molecular structures and are often present in multiple forms encoded by different genes. This work utilizes comparative genomics and phylogenetics for exploring the distribution, structure and evolution of phospholipid biosynthetic genes and pathways in 26 eukaryotic genomes. Although the basic structure of the pathways was formed early in eukaryotic evolution, the emerging picture indicates that individual enzyme families followed unique evolutionary courses. For example, choline and ethanolamine kinases and cytidylyltransferases emerged in ancestral eukaryotes, whereas, multiple forms of the corresponding phosphatidyltransferases evolved mainly in a lineage specific manner. Furthermore, several unicellular eukaryotes maintain bacterial-type enzymes and reactions for the synthesis of phosphatidylglycerol and cardiolipin. Also, base-exchange phosphatidylserine synthases are widespread and ancestral enzymes. The multiplicity of phospholipid biosynthetic enzymes has been largely generated by gene expansion in a lineage specific manner. Thus, these observations suggest that phospholipid biosynthesis has been an actively evolving system. Finally, comparative genomic analysis indicates the existence of novel phosphatidyltransferases and provides a candidate for the uncharacterized eukaryotic phosphatidylglycerol phosphate phosphatase.

  4. EMERGE: a flexible modelling framework to predict genomic regulatory elements from genomic signatures

    NARCIS (Netherlands)

    van Duijvenboden, Karel; de Boer, Bouke A.; Capon, Nicolas; Ruijter, Jan M.; Christoffels, Vincent M.

    2016-01-01

    Regulatory DNA elements, short genomic segments that regulate gene expression, have been implicated in developmental disorders and human disease. Despite this clinical urgency, only a small fraction of the regulatory DNA repertoire has been confirmed through reporter gene assays. The overall success

  5. Detecting Genomic Signatures of Natural Selection with Principal Component Analysis: Application to the 1000 Genomes Data.

    Science.gov (United States)

    Duforet-Frebourg, Nicolas; Luu, Keurcien; Laval, Guillaume; Bazin, Eric; Blum, Michael G B

    2016-04-01

    To characterize natural selection, various analytical methods for detecting candidate genomic regions have been developed. We propose to perform genome-wide scans of natural selection using principal component analysis (PCA). We show that the common FST index of genetic differentiation between populations can be viewed as the proportion of variance explained by the principal components. Considering the correlations between genetic variants and each principal component provides a conceptual framework to detect genetic variants involved in local adaptation without any prior definition of populations. To validate the PCA-based approach, we consider the 1000 Genomes data (phase 1) considering 850 individuals coming from Africa, Asia, and Europe. The number of genetic variants is of the order of 36 millions obtained with a low-coverage sequencing depth (3×). The correlations between genetic variation and each principal component provide well-known targets for positive selection (EDAR, SLC24A5, SLC45A2, DARC), and also new candidate genes (APPBPP2, TP1A1, RTTN, KCNMA, MYO5C) and noncoding RNAs. In addition to identifying genes involved in biological adaptation, we identify two biological pathways involved in polygenic adaptation that are related to the innate immune system (beta defensins) and to lipid metabolism (fatty acid omega oxidation). An additional analysis of European data shows that a genome scan based on PCA retrieves classical examples of local adaptation even when there are no well-defined populations. PCA-based statistics, implemented in the PCAdapt R package and the PCAdapt fast open-source software, retrieve well-known signals of human adaptation, which is encouraging for future whole-genome sequencing project, especially when defining populations is difficult. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  6. Genomic signatures amongOncorhynchus nerkaecotypes to inform conservation and management of endangered Sockeye Salmon.

    Science.gov (United States)

    Nichols, Krista M; Kozfkay, Christine C; Narum, Shawn R

    2016-12-01

    Conservation of life history variation is an important consideration for many species with trade-offs in migratory characteristics. Many salmonid species exhibit both resident and migratory strategies that capitalize on benefits in freshwater and marine environments. In this study, we investigated genomic signatures for migratory life history in collections of resident and anadromous Oncorhynchus nerka (Kokanee and Sockeye Salmon, respectively) from two lake systems, using ~2,600 SNPs from restriction-site-associated DNA sequencing (RAD-seq). Differing demographic histories were evident in the two systems where one pair was significantly differentiated (Redfish Lake, F ST  = 0.091 [95% confidence interval: 0.087 to 0.095]) but the other pair was not (Alturas Lake, F ST  = -0.007 [-0.008 to -0.006]). Outlier and association analyses identified several candidate markers in each population pair, but there was limited evidence for parallel signatures of genomic variation associated with migration. Despite lack of evidence for consistent markers associated with migratory life history in this species, candidate markers were mapped to functional genes and provide evidence for adaptive genetic variation within each lake system. Life history variation has been maintained in these nearly extirpated populations of O. nerka, and conservation efforts to preserve this diversity are important for long-term resiliency of this species.

  7. Detection of genomic signatures for pig hairlessness using high-density SNP data

    Directory of Open Access Journals (Sweden)

    Ying SU,Yi LONG,Xinjun LIAO,Huashui AI,Zhiyan ZHANG,Bin YANG,Shijun XIAO,Jianhong TANG,Wenshui XIN,Lusheng HUANG,Jun REN,Nengshui DING

    2014-12-01

    Full Text Available Hair provides thermal regulation for mammals and protects the skin from wounds, bites and ultraviolet (UV radiation, and is important in adaptation to volatile environments. Pigs in nature are divided into hairy and hairless, which provide a good model for deciphering the molecular mechanisms of hairlessness. We conducted a genomic scan for genetically differentiated regions between hairy and hairless pigs using 60K SNP data, with the aim to better understand the genetic basis for the hairless phenotype in pigs. A total of 38405 SNPs in 498 animals from 36 diverse breeds were used to detect genomic signatures for pig hairlessness by estimating between-population (FST values. Seven diversifying signatures between Yucatan hairless pig and hairy pigs were identified on pig chromosomes (SSC 1, 3, 7, 8, 10, 11 and 16, and the biological functions of two notable genes, RGS17 and RB1, were revealed. When Mexican hairless pigs were contrasted with hairypigs, strong signatures were detected on SSC1 and SSC10, which harbor two functionally plausible genes, REV3L and BAMBI. KEGG pathway analysis showed a subset of overrepresented genes involved in the T cell receptor signaling pathway, MAPK signaling pathway and the tight junction pathways. All of these pathways may be important in local adaptability of hairless pigs. The potential mechanisms underlying the hairless phenotype in pigs are reported for the first time. RB1 and BAMBI are interesting candidate genes for the hairless phenotype in Yucatan hairless and Mexico hairless pigs, respectively. RGS17, REV3L, ICOS and RASGRP1 as well as other genes involved in the MAPK and T cell receptor signaling pathways may be important in environmental adaption by improved tolerance to UV damage in hairless pigs. These findings improve our understanding of the genetic basis for inherited hairlessness in pigs.

  8. Genome-wide scans between two honeybee populations reveal putative signatures of human-mediated selection.

    Science.gov (United States)

    Parejo, M; Wragg, D; Henriques, D; Vignal, A; Neuditschko, M

    2017-12-01

    Human-mediated selection has left signatures in the genomes of many domesticated animals, including the European dark honeybee, Apis mellifera mellifera, which has been selected by apiculturists for centuries. Using whole-genome sequence information, we investigated selection signatures in spatially separated honeybee subpopulations (Switzerland, n = 39 and France, n = 17). Three different test statistics were calculated in windows of 2 kb (fixation index, cross-population extended haplotype homozygosity and cross-population composite likelihood ratio) and combined into a recently developed composite selection score. Applying a stringent false discovery rate of 0.01, we identified six significant selective sweeps distributed across five chromosomes covering eight genes. These genes are associated with multiple molecular and biological functions, including regulation of transcription, receptor binding and signal transduction. Of particular interest is a selection signature on chromosome 1, which corresponds to the WNT4 gene, the family of which is conserved across the animal kingdom with a variety of functions. In Drosophila melanogaster, WNT4 alleles have been associated with differential wing, cross vein and abdominal phenotypes. Defining phenotypic characteristics of different Apis mellifera ssp., which are typically used as selection criteria, include colour and wing venation pattern. This signal is therefore likely to be a good candidate for human mediated-selection arising from different applied breeding practices in the two managed populations. © 2017 The Authors. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.

  9. Approaches for Comparative Genomics in Aspergillus and Penicillium

    DEFF Research Database (Denmark)

    Rasmussen, Jane Lind Nybo; Theobald, Sebastian; Brandl, Julian

    2016-01-01

    of comparative genomics, ranging from analysis of single genes, over gene clusters and CaZymes to genome-scale comparative genomics. Furthermore, we have examined published comparative genomics papers to summarize the preferred bioinformatic methods and parameters for a given type of analysis, highly useful......The number of available genomes in the closely related fungal genera Aspergillus and Penicillium is rapidly increasing. At the time of writing, the genomes of 62 species are available, and an even higher number is being prepared. Fungal comparative genomics is thus becoming steadily more powerful...... and applicable for many types of studies. In this chapter, we provide an overview of the state-of-the-art of comparative genomics in these fungi, along with recommended methods. The chapter describes databases for fungal comparative genomics. Based on experience, we suggest strategies for multiple types...

  10. Comparative Genomics of Ten Solanaceous Plastomes

    Directory of Open Access Journals (Sweden)

    Harpreet Kaur

    2014-01-01

    Full Text Available Availability of complete plastid genomes of ten solanaceous species, Atropa belladonna, Capsicum annuum, Datura stramonium, Nicotiana sylvestris, Nicotiana tabacum, Nicotiana tomentosiformis, Nicotiana undulata, Solanum bulbocastanum, Solanum lycopersicum, and Solanum tuberosum provided us with an opportunity to conduct their in silico comparative analysis in depth. The size of complete chloroplast genomes and LSC and SSC regions of three species of Solanum is comparatively smaller than that of any other species studied till date (exception: SSC region of A. belladonna. AT content of coding regions was found to be less than noncoding regions. A duplicate copy of trnH gene in C. annuum and two alternative tRNA genes for proline in D. stramonium were observed for the first time in this analysis. Further, homology search revealed the presence of rps19 pseudogene and infA genes in A. belladonna and D. stramonium, a region identical to rps19 pseudogene in C. annum and orthologues of sprA gene in another six species. Among the eighteen intron-containing genes, 3 genes have two introns and 15 genes have one intron. The longest insertion was found in accD gene in C. annuum. Phylogenetic analysis using concatenated protein coding sequences gave two clades, one for Nicotiana species and another for Solanum, Capsicum, Atropa, and Datura.

  11. Quantitative analysis of comparative genomic hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Manoir, S. du; Bentz, M.; Joos, S. [Abteilung Organisation komplexer Genome, Heidelberg (Germany)]|[Institut fuer Humangenetik, Heidelberg (Germany)] [and others

    1995-01-01

    Comparative genomic hybridization (CGH) is a new molecular cytogenetic method for the detection of chromosomal imbalances. Following cohybridization of DNA prepared from a sample to be studied and control DNA to normal metaphase spreads, probes are detected via different fluorochromes. The ratio of the test and control fluorescence intensities along a chromosome reflects the relative copy number of segments of a chromosome in the test genome. Quantitative evaluation of CGH experiments is required for the determination of low copy changes, e.g., monosomy or trisomy, and for the definition of the breakpoints involved in unbalanced rearrangements. In this study, a program for quantitation of CGH preparations is presented. This program is based on the extraction of the fluorescence ratio profile along each chromosome, followed by averaging of individual profiles from several metaphase spreads. Objective parameters critical for quantitative evaluations were tested, and the criteria for selection of suitable CGH preparations are described. The granularity of the chromosome painting and the regional inhomogeneity of fluorescence intensities in metaphase spreads proved to be crucial parameters. The coefficient of variation of the ratio value for chromosomes in balanced state (CVBS) provides a general quality criterion for CGH experiments. Different cutoff levels (thresholds) of average fluorescence ratio values were compared for their specificity and sensitivity with regard to the detection of chromosomal imbalances. 27 refs., 15 figs., 1 tab.

  12. [Sotos syndrome diagnosed by comparative genomic hybridisation].

    Science.gov (United States)

    Saldarriaga, Wilmar; Molina-Barrera, Laura Camila; Ramírez-Cheyne, Julián

    2016-01-01

    Sotos Syndrome (SS) is a genetic disease with an autosomal dominant pattern caused by haplo-insufficiency of NSD1 gene secondary to point mutations or microdeletion of the 5q35 locus where the gene is located. It is a rare syndrome, occurring in 7 out of every 100,000 births. The objective of this report is to present the case of a 4 year-old patient with a global developmental delay, as well as specific physical findings suggesting a syndrome of genetic origin. Female patient, 4 years of age, thinning hair, triangular facie, long palpebral fissure, arched palate, prominent jaw, winged scapula and clinodactilia of the fifth finger both hands. The molecular test comparative genomic hybridisation test by microarray was subsequently performed, with the result showing 5q35.2 q35.3 region microdeletion of 2,082 MB, including the NSD1 gene. Finally, this article also proposes the performing of comparative genomic hybridisation as the first diagnostic option in cases where clinical findings are suggestive of SS. Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Comparative genomics of bifidobacterium, lactobacillus and related probiotic genera

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David; Wassenaar, Trudy M.

    2012-01-01

    Six bacterial genera containing species commonly used as probiotics for human consumption or starter cultures for food fermentation were compared and contrasted, based on publicly available complete genome sequences. The analysis included 19 Bifidobacterium genomes, 21 Lactobacillus genomes, 4...... Lactococcus and 3 Leuconostoc genomes, as well as a selection of Enterococcus (11) and Streptococcus (23) genomes. The latter two genera included genomes from probiotic or commensal as well as pathogenic organisms to investigate if their non-pathogenic members shared more genes with the other probiotic......- and core genome of each genus were compared. In addition, it was investigated whether pathogenic genomes contain different COG classes compared to the probiotic or fermentative organisms, again comparing their pan- and core genomes. The obtained results were compared with published data from the literature...

  14. Comparative Genome Analysis in the Integrated Microbial Genomes(IMG) System

    Energy Technology Data Exchange (ETDEWEB)

    Kyrpides, Nikos C.; Markowitz, Victor M.

    2006-03-01

    Comparative genome analysis is critical for the effectiveexploration of a rapidly growing number of complete and draft sequencesfor microbial genomes. The Integrated Microbial Genomes (IMG) system(img.jgi.doe.gov) has been developed as a community resource thatprovides support for comparative analysis of microbial genomes in anintegrated context. IMG allows users to navigate the multidimensionalmicrobial genome data space and focus their analysis on a subset ofgenes, genomes, and functions of interest. IMG provides graphicalviewers, summaries and occurrence profile tools for comparing genes,pathways and functions (terms) across specific genomes. Genes can befurther examined using gene neighborhoods and compared with sequencealignment tools.

  15. Polar bears exhibit genome-wide signatures of bioenergetic adaptation to life in the arctic environment.

    Science.gov (United States)

    Welch, Andreanna J; Bedoya-Reina, Oscar C; Carretero-Paulet, Lorenzo; Miller, Webb; Rode, Karyn D; Lindqvist, Charlotte

    2014-02-01

    Polar bears (Ursus maritimus) face extremely cold temperatures and periods of fasting, which might result in more severe energetic challenges than those experienced by their sister species, the brown bear (U. arctos). We have examined the mitochondrial and nuclear genomes of polar and brown bears to investigate whether polar bears demonstrate lineage-specific signals of molecular adaptation in genes associated with cellular respiration/energy production. We observed increased evolutionary rates in the mitochondrial cytochrome c oxidase I gene in polar but not brown bears. An amino acid substitution occurred near the interaction site with a nuclear-encoded subunit of the cytochrome c oxidase complex and was predicted to lead to a functional change, although the significance of this remains unclear. The nuclear genomes of brown and polar bears demonstrate different adaptations related to cellular respiration. Analyses of the genomes of brown bears exhibited substitutions that may alter the function of proteins that regulate glucose uptake, which could be beneficial when feeding on carbohydrate-dominated diets during hyperphagia, followed by fasting during hibernation. In polar bears, genes demonstrating signatures of functional divergence and those potentially under positive selection were enriched in functions related to production of nitric oxide (NO), which can regulate energy production in several different ways. This suggests that polar bears may be able to fine-tune intracellular levels of NO as an adaptive response to control trade-offs between energy production in the form of adenosine triphosphate versus generation of heat (thermogenesis).

  16. Polar bears exhibit genome-wide signatures of bioenergetic adaptation to life in the Arctic environment

    Science.gov (United States)

    Welch, Andreanna J.; Bedoya-Reina, Oscar C.; Carretero-Paulet, Lorenzo; Miller, Webb; Rode, Karyn D.; Lindqvist, Charlotte

    2014-01-01

    Polar bears (Ursus maritimus) face extremely cold temperatures and periods of fasting, which might result in more severe energetic challenges than those experienced by their sister species, the brown bear (U. arctos). We have examined the mitochondrial and nuclear genomes of polar and brown bears to investigate if polar bears demonstrate lineage-specific signals of molecular adaptation in genes associated with cellular respiration/energy production. We observed increased evolutionary rates in the mitochondrial cytochrome c oxidase I gene in polar but not brown bears. An amino acid substitution occurred near the interaction site with a nuclear-encoded subunit of the cytochrome c oxidase complex, and was predicted to lead to a functional change, although the significance of this remains unclear. The nuclear genomes of brown and polar bears demonstrate different adaptations related to cellular respiration. Analyses of the genomes of brown bears exhibited substitutions that may alter the function of proteins that regulate glucose uptake, which could be beneficial when feeding on carbohydrate-dominated diets during hyperphagia, followed by fasting during hibernation. In polar bears, genes demonstrating signatures of functional divergence and those potentially under positive selection were enriched in functions related to production of nitric oxide, which can regulate energy production in several different ways. This suggests that polar bears may be able to fine-tune intracellular levels of nitric oxide as an adaptive response to control trade-offs between energy production in the form of ATP versus generation of heat (thermogenesis).

  17. Discovery of functional elements in 12 Drosophila genomes using evolutionary signatures

    DEFF Research Database (Denmark)

    Stark, Alexander; Lin, Michael F; Kheradpour, Pouya

    2007-01-01

    -codon readthrough. Similarly, we predict non-protein-coding RNA genes and structures, and new microRNA (miRNA) genes. We provide evidence of miRNA processing and functionality from both hairpin arms and both DNA strands. We identify several classes of pre- and post-transcriptional regulatory motifs, and predict......Sequencing of multiple related species followed by comparative genomics analysis constitutes a powerful approach for the systematic understanding of any genome. Here, we use the genomes of 12 Drosophila species for the de novo discovery of functional elements in the fly. Each type of functional...

  18. Genome-wide mapping of DNase hypersensitive sites using massively parallel signature sequencing (MPSS).

    Science.gov (United States)

    Crawford, Gregory E; Holt, Ingeborg E; Whittle, James; Webb, Bryn D; Tai, Denise; Davis, Sean; Margulies, Elliott H; Chen, YiDong; Bernat, John A; Ginsburg, David; Zhou, Daixing; Luo, Shujun; Vasicek, Thomas J; Daly, Mark J; Wolfsberg, Tyra G; Collins, Francis S

    2006-01-01

    A major goal in genomics is to understand how genes are regulated in different tissues, stages of development, diseases, and species. Mapping DNase I hypersensitive (HS) sites within nuclear chromatin is a powerful and well-established method of identifying many different types of regulatory elements, but in the past it has been limited to analysis of single loci. We have recently described a protocol to generate a genome-wide library of DNase HS sites. Here, we report high-throughput analysis, using massively parallel signature sequencing (MPSS), of 230,000 tags from a DNase library generated from quiescent human CD4+ T cells. Of the tags that uniquely map to the genome, we identified 14,190 clusters of sequences that group within close proximity to each other. By using a real-time PCR strategy, we determined that the majority of these clusters represent valid DNase HS sites. Approximately 80% of these DNase HS sites uniquely map within one or more annotated regions of the genome believed to contain regulatory elements, including regions 2 kb upstream of genes, CpG islands, and highly conserved sequences. Most DNase HS sites identified in CD4+ T cells are also HS in CD8+ T cells, B cells, hepatocytes, human umbilical vein endothelial cells (HUVECs), and HeLa cells. However, approximately 10% of the DNase HS sites are lymphocyte specific, indicating that this procedure can identify gene regulatory elements that control cell type specificity. This strategy, which can be applied to any cell line or tissue, will enable a better understanding of how chromatin structure dictates cell function and fate.

  19. Comparative genomics of emerging human ehrlichiosis agents.

    Directory of Open Access Journals (Sweden)

    Julie C Dunning Hotopp

    2006-02-01

    Full Text Available Anaplasma (formerly Ehrlichia phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens.

  20. Comparative genomics reveals insights into avian genome evolution and adaptation

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Cai; Li, Qiye

    2014-01-01

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size...... this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits....

  1. The bonobo genome compared with the chimpanzee and human genomes

    Science.gov (United States)

    Prüfer, Kay; Munch, Kasper; Hellmann, Ines; Akagi, Keiko; Miller, Jason R.; Walenz, Brian; Koren, Sergey; Sutton, Granger; Kodira, Chinnappa; Winer, Roger; Knight, James R.; Mullikin, James C.; Meader, Stephen J.; Ponting, Chris P.; Lunter, Gerton; Higashino, Saneyuki; Hobolth, Asger; Dutheil, Julien; Karakoç, Emre; Alkan, Can; Sajjadian, Saba; Catacchio, Claudia Rita; Ventura, Mario; Marques-Bonet, Tomas; Eichler, Evan E.; André, Claudine; Atencia, Rebeca; Mugisha, Lawrence; Junhold, Jörg; Patterson, Nick; Siebauer, Michael; Good, Jeffrey M.; Fischer, Anne; Ptak, Susan E.; Lachmann, Michael; Symer, David E.; Mailund, Thomas; Schierup, Mikkel H.; Andrés, Aida M.; Kelso, Janet; Pääbo, Svante

    2012-01-01

    Two African apes are the closest living relatives of humans: the chimpanzee (Pan troglodytes) and the bonobo (Pan paniscus). Although they are similar in many respects, bonobos and chimpanzees differ strikingly in key social and sexual behaviours1–4, and for some of these traits they show more similarity with humans than with each other. Here we report the sequencing and assembly of the bonobo genome to study its evolutionary relationship with the chimpanzee and human genomes. We find that more than three per cent of the human genome is more closely related to either the bonobo or the chimpanzee genome than these are to each other. These regions allow various aspects of the ancestry of the two ape species to be reconstructed. In addition, many of the regions that overlap genes may eventually help us understand the genetic basis of phenotypes that humans share with one of the two apes to the exclusion of the other. PMID:22722832

  2. Multiscale landscape genomic models to detect signatures of selection in the alpine plant Biscutella laevigata.

    Science.gov (United States)

    Leempoel, Kevin; Parisod, Christian; Geiser, Céline; Joost, Stéphane

    2018-02-01

    Plant species are known to adapt locally to their environment, particularly in mountainous areas where conditions can vary drastically over short distances. The climate of such landscapes being largely influenced by topography, using fine-scale models to evaluate environmental heterogeneity may help detecting adaptation to micro-habitats. Here, we applied a multiscale landscape genomic approach to detect evidence of local adaptation in the alpine plant Biscutella laevigata . The two gene pools identified, experiencing limited gene flow along a 1-km ridge, were different in regard to several habitat features derived from a very high resolution (VHR) digital elevation model (DEM). A correlative approach detected signatures of selection along environmental gradients such as altitude, wind exposure, and solar radiation, indicating adaptive pressures likely driven by fine-scale topography. Using a large panel of DEM-derived variables as ecologically relevant proxies, our results highlighted the critical role of spatial resolution. These high-resolution multiscale variables indeed indicate that the robustness of associations between genetic loci and environmental features depends on spatial parameters that are poorly documented. We argue that the scale issue is critical in landscape genomics and that multiscale ecological variables are key to improve our understanding of local adaptation in highly heterogeneous landscapes.

  3. Genome-wide signatures of differential DNA methylation in pediatric acute lymphoblastic leukemia

    DEFF Research Database (Denmark)

    Nordlund, Jessica; Bäcklin, Christofer L; Wahlberg, Per

    2013-01-01

    background, drug resistance and relapse in ALL is poorly understood. RESULTS: We surveyed the DNA methylation levels of 435,941 CpG sites in samples from 764 children at diagnosis of ALL and from 27 children at relapse. This survey uncovered four characteristic methylation signatures. First, compared...... cells at relapse, compared with matched samples at diagnosis. Analysis of relapse-free survival identified CpG sites with subtype-specific differential methylation that divided the patients into different risk groups, depending on their methylation status. CONCLUSIONS: Our results suggest an important...... biological role for DNA methylation in the differences between ALL subtypes and in their clinical outcome after treatment....

  4. Within-Host Variations of Human Papillomavirus Reveal APOBEC-Signature Mutagenesis in the Viral Genome.

    Science.gov (United States)

    Hirose, Yusuke; Onuki, Mamiko; Tenjimbayashi, Yuri; Mori, Seiichiro; Ishii, Yoshiyuki; Takeuchi, Takamasa; Tasaka, Nobutaka; Satoh, Toyomi; Morisada, Tohru; Iwata, Takashi; Miyamoto, Shingo; Matsumoto, Koji; Sekizawa, Akihiko; Kukimoto, Iwao

    2018-03-28

    Persistent infection with oncogenic human papillomaviruses (HPVs) causes cervical cancer, accompanied with the accumulation of somatic mutations into the host genome. There are concomitant genetic changes in the HPV genome during viral infection; however, their relevance to cervical carcinogenesis is poorly understood. Here we explored within-host genetic diversity of HPV by performing deep sequencing analyses of viral whole-genome sequences in clinical specimens. The whole genomes of HPV types 16, 52 and 58 were amplified by type-specific PCR from total cellular DNA of cervical exfoliated cells collected from patients with cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC), and were deep-sequenced. After constructing a reference vial genome sequence for each specimen, nucleotide positions showing changes with > 0.5% frequencies compared to the reference sequence were determined for individual samples. In total, 1,052 positions of nucleotide variations were detected in HPV genomes from 151 samples (CIN1, n = 56; CIN2/3, n = 68; ICC, n = 27), with varying numbers per sample. Overall, C-to-T and C-to-A substitutions were the dominant changes observed across all histological grades. While C-to-T transitions were predominantly detected in CIN1, their prevalence was decreased in CIN2/3 and fell below that of C-to-A transversions in ICC. Analysis of the tri-nucleotides context encompassing substituted bases revealed that Tp C pN, a preferred target sequence for cellular APOBEC cytosine deaminases, was a primary site for C-to-T substitutions in the HPV genome. These results strongly imply that the APOBEC proteins are drivers of HPV genome mutation, particularly in CIN1 lesions. IMPORTANCE HPVs exhibit surprisingly high levels of genetic diversity, including a large repertoire of minor genomic variants in each viral genotype. Here, by conducting deep sequencing analyses, we show for the first time a comprehensive snapshot of the "within

  5. Comparative chloroplast genomes of camellia species.

    Directory of Open Access Journals (Sweden)

    Jun-Bo Yang

    Full Text Available BACKGROUND: Camellia, comprising more than 200 species, is a valuable economic commodity due to its enormously popular commercial products: tea leaves, flowers, and high-quality edible oils. It is the largest and most important genus in the family Theaceae. However, phylogenetic resolution of the species has proven to be difficult. Consequently, the interspecies relationships of the genus Camellia are still hotly debated. Phylogenomics is an attractive avenue that can be used to reconstruct the tree of life, especially at low taxonomic levels. METHODOLOGY/PRINCIPAL FINDINGS: Seven complete chloroplast (cp genomes were sequenced from six species representing different subdivisions of the genus Camellia using Illumina sequencing technology. Four junctions between the single-copy segments and the inverted repeats were confirmed and genome assemblies were validated by PCR-based product sequencing using 123 pairs of primers covering preliminary cp genome assemblies. The length of the Camellia cp genome was found to be about 157kb, which contained 123 unique genes and 23 were duplicated in the IR regions. We determined that the complete Camellia cp genome was relatively well conserved, but contained enough genetic differences to provide useful phylogenetic information. Phylogenetic relationships were analyzed using seven complete cp genomes of six Camellia species. We also identified rapidly evolving regions of the cp genome that have the potential to be used for further species identification and phylogenetic resolution. CONCLUSIONS/SIGNIFICANCE: In this study, we wanted to determine if analyzing completely sequenced cp genomes could help settle these controversies of interspecies relationships in Camellia. The results demonstrate that cp genome data are beneficial in resolving species definition because they indicate that organelle-based "barcodes", can be established for a species and then used to unmask interspecies phylogenetic relationships. It

  6. Comparative genomic hybridization in clinical cytogenetics

    Energy Technology Data Exchange (ETDEWEB)

    Bryndorf, T.; Kirchhoff, M.; Rose, H. [and others

    1995-11-01

    We report the results of applying comparative genomic hybridization (CGH) in a cytogenetic service laboratory for (1) determination of the origin of extra and missing chromosomal material in intricate cases of unbalanced aberrations and (2) detection of common prenatal numerical chromosome aberrations. A total of 11 fetal samples were analyzed. Seven cases of complex unbalanced aberrations that could not be identified reliably by conventional cytogenetics were successfully resolved by CGH analysis. CGH results were validated by using FISH with chromosome-specific probes. Four cases representing common prenatal numerical aberrations (trisomy 21, 18, and 13 and monosomy X) were also successfully diagnosed by CGH. We conclude that CGH is a powerful adjunct to traditional cytogenetic techniques that makes it possible to solve clinical cases of intricate unbalanced aberrations in a single hybridization. CGH may also be a useful adjunct to screen for euchromatic involvement in marker chromosomes. Further technical development may render CGH applicable for routine aberration screening. 16 refs., 4 figs., 2 tabs.

  7. Comparative genomic in situ hybridization analysis on the ...

    African Journals Online (AJOL)

    Comparative genomic in situ hybridization (cGISH) with biotin-labeled rice genomic DNA to the chromosomes of Zea mays, Hordeum vulgare, Sorghum bicolor, Setaria italic and Secale cereale were conducted to analyze genomic homology between rice and other grass (Gramineae) speices. At 75% stringency, the rice ...

  8. Genome-wide comparative analysis of four Indian Drosophila species.

    Science.gov (United States)

    Mohanty, Sujata; Khanna, Radhika

    2017-12-01

    Comparative analysis of multiple genomes of closely or distantly related Drosophila species undoubtedly creates excitement among evolutionary biologists in exploring the genomic changes with an ecology and evolutionary perspective. We present herewith the de novo assembled whole genome sequences of four Drosophila species, D. bipectinata, D. takahashii, D. biarmipes and D. nasuta of Indian origin using Next Generation Sequencing technology on an Illumina platform along with their detailed assembly statistics. The comparative genomics analysis, e.g. gene predictions and annotations, functional and orthogroup analysis of coding sequences and genome wide SNP distribution were performed. The whole genome of Zaprionus indianus of Indian origin published earlier by us and the genome sequences of previously sequenced 12 Drosophila species available in the NCBI database were included in the analysis. The present work is a part of our ongoing genomics project of Indian Drosophila species.

  9. Transcriptomic signatures shaped by cell proportions shed light on comparative developmental biology

    Czech Academy of Sciences Publication Activity Database

    Pantalacci, S.; Gueguen, L.; Petit, C.; Lambert, A.; Peterková, Renata; Sémon, E.

    2017-01-01

    Roč. 18, feb (2017), s. 29 ISSN 1474-760X R&D Projects: GA ČR(CZ) GB14-37368G Institutional support: RVO:68378041 Keywords : comparative transcriptomics * developmental biology * transcriptomic signature Subject RIV: EA - Cell Biology OBOR OECD: Developmental biology Impact factor: 11.908, year: 2016

  10. Cancer clinical trials in the era of genomic signatures: biomedical innovation, clinical utility, and regulatory-scientific hybrids.

    Science.gov (United States)

    Kohli-Laven, Nina; Bourret, Pascale; Keating, Peter; Cambrosio, Alberto

    2011-08-01

    The paper examines two large-scale, North American and European clinical trials designed to validate two commercially available genomic tumor signatures that predict a patient's risk of breast cancer recurrence and response to chemotherapy. The paper builds on empirical evidence from the two trials to explore the emergence of diverse regulatory-scientific hybrids; that is, the paper discusses configurations of genomic practice and bioclinical work that depend on linkages between technical, commercial, patient, clinical, and legal interests and institutions. The development of the genomic signatures for each trial--Oncotype DX and MammaPrint--has followed quite different routes. Oncotype began as a commercial platform: the company that produced it did not discover a signature but rather constructed it by asking users at every step what clinical question they wanted the signature to answer and what data would be credible in that regard. The test has been designed to minimally disrupt existing clinical workflows. MammaPrint, on the other hand, began as a breast cancer signature: the researchers who discovered it, at the Netherlands Cancer Institute (NKI), established a company to commercialize it as a test after the fact. MammaPrint requires a change in pathologists' routines. Thus, while these two trials signify a new departure for clinical cancer trials on a number of levels--they both incorporate new models of interaction between biotech companies and public research, and they both aim to establish the clinical relevance of genomic markers--they also embody different socio-technical scripts: one attempts to accommodate established routines, while the other openly challenges prevailing evidential hierarchies and existing biomedical configurations.

  11. Classification and regression tree (CART) analyses of genomic signatures reveal sets of tetramers that discriminate temperature optima of archaea and bacteria

    Science.gov (United States)

    Dyer, Betsey D.; Kahn, Michael J.; LeBlanc, Mark D.

    2008-01-01

    Classification and regression tree (CART) analysis was applied to genome-wide tetranucleotide frequencies (genomic signatures) of 195 archaea and bacteria. Although genomic signatures have typically been used to classify evolutionary divergence, in this study, convergent evolution was the focus. Temperature optima for most of the organisms examined could be distinguished by CART analyses of tetranucleotide frequencies. This suggests that pervasive (nonlinear) qualities of genomes may reflect certain environmental conditions (such as temperature) in which those genomes evolved. The predominant use of GAGA and AGGA as the discriminating tetramers in CART models suggests that purine-loading and codon biases of thermophiles may explain some of the results. PMID:19054742

  12. Identifying signatures of natural selection in Tibetan and Andean populations using dense genome scan data.

    Science.gov (United States)

    Bigham, Abigail; Bauchet, Marc; Pinto, Dalila; Mao, Xianyun; Akey, Joshua M; Mei, Rui; Scherer, Stephen W; Julian, Colleen G; Wilson, Megan J; López Herráez, David; Brutsaert, Tom; Parra, Esteban J; Moore, Lorna G; Shriver, Mark D

    2010-09-09

    High-altitude hypoxia (reduced inspired oxygen tension due to decreased barometric pressure) exerts severe physiological stress on the human body. Two high-altitude regions where humans have lived for millennia are the Andean Altiplano and the Tibetan Plateau. Populations living in these regions exhibit unique circulatory, respiratory, and hematological adaptations to life at high altitude. Although these responses have been well characterized physiologically, their underlying genetic basis remains unknown. We performed a genome scan to identify genes showing evidence of adaptation to hypoxia. We looked across each chromosome to identify genomic regions with previously unknown function with respect to altitude phenotypes. In addition, groups of genes functioning in oxygen metabolism and sensing were examined to test the hypothesis that particular pathways have been involved in genetic adaptation to altitude. Applying four population genetic statistics commonly used for detecting signatures of natural selection, we identified selection-nominated candidate genes and gene regions in these two populations (Andeans and Tibetans) separately. The Tibetan and Andean patterns of genetic adaptation are largely distinct from one another, with both populations showing evidence of positive natural selection in different genes or gene regions. Interestingly, one gene previously known to be important in cellular oxygen sensing, EGLN1 (also known as PHD2), shows evidence of positive selection in both Tibetans and Andeans. However, the pattern of variation for this gene differs between the two populations. Our results indicate that several key HIF-regulatory and targeted genes are responsible for adaptation to high altitude in Andeans and Tibetans, and several different chromosomal regions are implicated in the putative response to selection. These data suggest a genetic role in high-altitude adaption and provide a basis for future genotype/phenotype association studies necessary

  13. Identifying signatures of natural selection in Tibetan and Andean populations using dense genome scan data.

    Directory of Open Access Journals (Sweden)

    Abigail Bigham

    2010-09-01

    Full Text Available High-altitude hypoxia (reduced inspired oxygen tension due to decreased barometric pressure exerts severe physiological stress on the human body. Two high-altitude regions where humans have lived for millennia are the Andean Altiplano and the Tibetan Plateau. Populations living in these regions exhibit unique circulatory, respiratory, and hematological adaptations to life at high altitude. Although these responses have been well characterized physiologically, their underlying genetic basis remains unknown. We performed a genome scan to identify genes showing evidence of adaptation to hypoxia. We looked across each chromosome to identify genomic regions with previously unknown function with respect to altitude phenotypes. In addition, groups of genes functioning in oxygen metabolism and sensing were examined to test the hypothesis that particular pathways have been involved in genetic adaptation to altitude. Applying four population genetic statistics commonly used for detecting signatures of natural selection, we identified selection-nominated candidate genes and gene regions in these two populations (Andeans and Tibetans separately. The Tibetan and Andean patterns of genetic adaptation are largely distinct from one another, with both populations showing evidence of positive natural selection in different genes or gene regions. Interestingly, one gene previously known to be important in cellular oxygen sensing, EGLN1 (also known as PHD2, shows evidence of positive selection in both Tibetans and Andeans. However, the pattern of variation for this gene differs between the two populations. Our results indicate that several key HIF-regulatory and targeted genes are responsible for adaptation to high altitude in Andeans and Tibetans, and several different chromosomal regions are implicated in the putative response to selection. These data suggest a genetic role in high-altitude adaption and provide a basis for future genotype/phenotype association

  14. Initial sequencing and comparative analysis of the mouse genome.

    Science.gov (United States)

    Waterston, Robert H; Lindblad-Toh, Kerstin; Birney, Ewan; Rogers, Jane; Abril, Josep F; Agarwal, Pankaj; Agarwala, Richa; Ainscough, Rachel; Alexandersson, Marina; An, Peter; Antonarakis, Stylianos E; Attwood, John; Baertsch, Robert; Bailey, Jonathon; Barlow, Karen; Beck, Stephan; Berry, Eric; Birren, Bruce; Bloom, Toby; Bork, Peer; Botcherby, Marc; Bray, Nicolas; Brent, Michael R; Brown, Daniel G; Brown, Stephen D; Bult, Carol; Burton, John; Butler, Jonathan; Campbell, Robert D; Carninci, Piero; Cawley, Simon; Chiaromonte, Francesca; Chinwalla, Asif T; Church, Deanna M; Clamp, Michele; Clee, Christopher; Collins, Francis S; Cook, Lisa L; Copley, Richard R; Coulson, Alan; Couronne, Olivier; Cuff, James; Curwen, Val; Cutts, Tim; Daly, Mark; David, Robert; Davies, Joy; Delehaunty, Kimberly D; Deri, Justin; Dermitzakis, Emmanouil T; Dewey, Colin; Dickens, Nicholas J; Diekhans, Mark; Dodge, Sheila; Dubchak, Inna; Dunn, Diane M; Eddy, Sean R; Elnitski, Laura; Emes, Richard D; Eswara, Pallavi; Eyras, Eduardo; Felsenfeld, Adam; Fewell, Ginger A; Flicek, Paul; Foley, Karen; Frankel, Wayne N; Fulton, Lucinda A; Fulton, Robert S; Furey, Terrence S; Gage, Diane; Gibbs, Richard A; Glusman, Gustavo; Gnerre, Sante; Goldman, Nick; Goodstadt, Leo; Grafham, Darren; Graves, Tina A; Green, Eric D; Gregory, Simon; Guigó, Roderic; Guyer, Mark; Hardison, Ross C; Haussler, David; Hayashizaki, Yoshihide; Hillier, LaDeana W; Hinrichs, Angela; Hlavina, Wratko; Holzer, Timothy; Hsu, Fan; Hua, Axin; Hubbard, Tim; Hunt, Adrienne; Jackson, Ian; Jaffe, David B; Johnson, L Steven; Jones, Matthew; Jones, Thomas A; Joy, Ann; Kamal, Michael; Karlsson, Elinor K; Karolchik, Donna; Kasprzyk, Arkadiusz; Kawai, Jun; Keibler, Evan; Kells, Cristyn; Kent, W James; Kirby, Andrew; Kolbe, Diana L; Korf, Ian; Kucherlapati, Raju S; Kulbokas, Edward J; Kulp, David; Landers, Tom; Leger, J P; Leonard, Steven; Letunic, Ivica; Levine, Rosie; Li, Jia; Li, Ming; Lloyd, Christine; Lucas, Susan; Ma, Bin; Maglott, Donna R; Mardis, Elaine R; Matthews, Lucy; Mauceli, Evan; Mayer, John H; McCarthy, Megan; McCombie, W Richard; McLaren, Stuart; McLay, Kirsten; McPherson, John D; Meldrim, Jim; Meredith, Beverley; Mesirov, Jill P; Miller, Webb; Miner, Tracie L; Mongin, Emmanuel; Montgomery, Kate T; Morgan, Michael; Mott, Richard; Mullikin, James C; Muzny, Donna M; Nash, William E; Nelson, Joanne O; Nhan, Michael N; Nicol, Robert; Ning, Zemin; Nusbaum, Chad; O'Connor, Michael J; Okazaki, Yasushi; Oliver, Karen; Overton-Larty, Emma; Pachter, Lior; Parra, Genís; Pepin, Kymberlie H; Peterson, Jane; Pevzner, Pavel; Plumb, Robert; Pohl, Craig S; Poliakov, Alex; Ponce, Tracy C; Ponting, Chris P; Potter, Simon; Quail, Michael; Reymond, Alexandre; Roe, Bruce A; Roskin, Krishna M; Rubin, Edward M; Rust, Alistair G; Santos, Ralph; Sapojnikov, Victor; Schultz, Brian; Schultz, Jörg; Schwartz, Matthias S; Schwartz, Scott; Scott, Carol; Seaman, Steven; Searle, Steve; Sharpe, Ted; Sheridan, Andrew; Shownkeen, Ratna; Sims, Sarah; Singer, Jonathan B; Slater, Guy; Smit, Arian; Smith, Douglas R; Spencer, Brian; Stabenau, Arne; Stange-Thomann, Nicole; Sugnet, Charles; Suyama, Mikita; Tesler, Glenn; Thompson, Johanna; Torrents, David; Trevaskis, Evanne; Tromp, John; Ucla, Catherine; Ureta-Vidal, Abel; Vinson, Jade P; Von Niederhausern, Andrew C; Wade, Claire M; Wall, Melanie; Weber, Ryan J; Weiss, Robert B; Wendl, Michael C; West, Anthony P; Wetterstrand, Kris; Wheeler, Raymond; Whelan, Simon; Wierzbowski, Jamey; Willey, David; Williams, Sophie; Wilson, Richard K; Winter, Eitan; Worley, Kim C; Wyman, Dudley; Yang, Shan; Yang, Shiaw-Pyng; Zdobnov, Evgeny M; Zody, Michael C; Lander, Eric S

    2002-12-05

    The sequence of the mouse genome is a key informational tool for understanding the contents of the human genome and a key experimental tool for biomedical research. Here, we report the results of an international collaboration to produce a high-quality draft sequence of the mouse genome. We also present an initial comparative analysis of the mouse and human genomes, describing some of the insights that can be gleaned from the two sequences. We discuss topics including the analysis of the evolutionary forces shaping the size, structure and sequence of the genomes; the conservation of large-scale synteny across most of the genomes; the much lower extent of sequence orthology covering less than half of the genomes; the proportions of the genomes under selection; the number of protein-coding genes; the expansion of gene families related to reproduction and immunity; the evolution of proteins; and the identification of intraspecies polymorphism.

  15. Genome-wide allele-specific expression analysis using Massively Parallel Signature Sequencing (MPSS) reveals cis- and trans-effects on gene expression in maize hybrid meristem tissue.

    Science.gov (United States)

    Guo, Mei; Yang, Sean; Rupe, Mary; Hu, Bin; Bickel, David R; Arthur, Lane; Smith, Oscar

    2008-03-01

    Allelic differences in expression are important genetic factors contributing to quantitative trait variation in various organisms. However, the extent of genome-wide allele-specific expression by different modes of gene regulation has not been well characterized in plants. In this study we developed a new methodology for allele-specific expression analysis by applying Massively Parallel Signature Sequencing (MPSS), an open ended and sequencing based mRNA profiling technology. This methodology enabled a genome-wide evaluation of cis- and trans-effects on allelic expression in six meristem stages of the maize hybrid. Summarization of data from nearly 400 pairs of MPSS allelic signature tags showed that 60% of the genes in the hybrid meristems exhibited differential allelic expression. Because both alleles are subjected to the same trans-acting factors in the hybrid, the data suggest the abundance of cis-regulatory differences in the genome. Comparing the same allele expressed in the hybrid versus its inbred parents showed that 40% of the genes were differentially expressed, suggesting different trans-acting effects present in different genotypes. Such trans-acting effects may result in gene expression in the hybrid different from allelic additive expression. With this approach we quantified gene expression in the hybrid relative to its inbred parents at the allele-specific level. As compared to measuring total transcript levels, this study provides a new level of understanding of different modes of gene regulation in the hybrid and the molecular basis of heterosis.

  16. The genome, transcriptome, and proteome of the nematode Steinernema carpocapsae: evolutionary signatures of a pathogenic lifestyle.

    Science.gov (United States)

    Rougon-Cardoso, Alejandra; Flores-Ponce, Mitzi; Ramos-Aboites, Hilda Eréndira; Martínez-Guerrero, Christian Eduardo; Hao, You-Jin; Cunha, Luis; Rodríguez-Martínez, Jonathan Alejandro; Ovando-Vázquez, Cesaré; Bermúdez-Barrientos, José Roberto; Abreu-Goodger, Cei; Chavarría-Hernández, Norberto; Simões, Nelson; Montiel, Rafael

    2016-11-23

    The entomopathogenic nematode Steinernema carpocapsae has been widely used for the biological control of insect pests. It shares a symbiotic relationship with the bacterium Xenorhabdus nematophila, and is emerging as a genetic model to study symbiosis and pathogenesis. We obtained a high-quality draft of the nematode's genome comprising 84,613,633 bp in 347 scaffolds, with an N50 of 1.24 Mb. To improve annotation, we sequenced both short and long RNA and conducted shotgun proteomic analyses. S. carpocapsae shares orthologous genes with other parasitic nematodes that are absent in the free-living nematode C. elegans, it has ncRNA families that are enriched in parasites, and expresses proteins putatively associated with parasitism and pathogenesis, suggesting an active role for the nematode during the pathogenic process. Host and parasites might engage in a co-evolutionary arms-race dynamic with genes participating in their interaction showing signatures of positive selection. Our analyses indicate that the consequence of this arms race is better characterized by positive selection altering specific functions instead of just increasing the number of positively selected genes, adding a new perspective to these co-evolutionary theories. We identified a protein, ATAD-3, that suggests a relevant role for mitochondrial function in the evolution and mechanisms of nematode parasitism.

  17. The Genomic Signature of Population Reconnection Following Isolation: From Theory to HIV

    Directory of Open Access Journals (Sweden)

    Nicolas Alcala

    2016-01-01

    Full Text Available Ease of worldwide travel provides increased opportunities for organisms not only to colonize new environments but also to encounter related but diverged populations. Such events of reconnection and secondary contact of previously isolated populations are widely observed at different time scales. For example, during the quaternary glaciation, sea water level fluctuations caused temporal isolation of populations, often to be followed by secondary contact. At shorter time scales, population isolation and reconnection of viruses are commonly observed, and such events are often associated with epidemics and pandemics. Here, using coalescent theory and simulations, we describe the temporal impact of population reconnection after isolation on nucleotide differences and the site frequency spectrum, as well as common summary statistics of DNA variation. We identify robust genomic signatures of population reconnection after isolation. We utilize our development to infer the recent evolutionary history of human immunodeficiency virus 1 (HIV-1 in Asia and South America, successfully retrieving the successive HIV subtype colonization events in these regions. Our analysis reveals that divergent HIV-1 subtype populations are currently admixing in these regions, suggesting that HIV-1 may be undergoing a process of homogenization, contrary to popular belief.

  18. Comparative genomics of Cluster O mycobacteriophages.

    Directory of Open Access Journals (Sweden)

    Steven G Cresawn

    Full Text Available Mycobacteriophages--viruses of mycobacterial hosts--are genetically diverse but morphologically are all classified in the Caudovirales with double-stranded DNA and tails. We describe here a group of five closely related mycobacteriophages--Corndog, Catdawg, Dylan, Firecracker, and YungJamal--designated as Cluster O with long flexible tails but with unusual prolate capsids. Proteomic analysis of phage Corndog particles, Catdawg particles, and Corndog-infected cells confirms expression of half of the predicted gene products and indicates a non-canonical mechanism for translation of the Corndog tape measure protein. Bioinformatic analysis identifies 8-9 strongly predicted SigA promoters and all five Cluster O genomes contain more than 30 copies of a 17 bp repeat sequence with dyad symmetry located throughout the genomes. Comparison of the Cluster O phages provides insights into phage genome evolution including the processes of gene flux by horizontal genetic exchange.

  19. Comparative analysis of Salmonella genomes identifies a metabolic network for escalating growth in the inflamed gut.

    Science.gov (United States)

    Nuccio, Sean-Paul; Bäumler, Andreas J

    2014-03-18

    The Salmonella genus comprises a group of pathogens associated with illnesses ranging from gastroenteritis to typhoid fever. We performed an in silico analysis of comparatively reannotated Salmonella genomes to identify genomic signatures indicative of disease potential. By removing numerous annotation inconsistencies and inaccuracies, the process of reannotation identified a network of 469 genes involved in central anaerobic metabolism, which was intact in genomes of gastrointestinal pathogens but degrading in genomes of extraintestinal pathogens. This large network contained pathways that enable gastrointestinal pathogens to utilize inflammation-derived nutrients as well as many of the biochemical reactions used for the enrichment and biochemical discrimination of Salmonella serovars. Thus, comparative genome analysis identifies a metabolic network that provides clues about the strategies for nutrient acquisition and utilization that are characteristic of gastrointestinal pathogens. IMPORTANCE While some Salmonella serovars cause infections that remain localized to the gut, others disseminate throughout the body. Here, we compared Salmonella genomes to identify characteristics that distinguish gastrointestinal from extraintestinal pathogens. We identified a large metabolic network that is functional in gastrointestinal pathogens but decaying in extraintestinal pathogens. While taxonomists have used traits from this network empirically for many decades for the enrichment and biochemical discrimination of Salmonella serovars, our findings suggest that it is part of a "business plan" for growth in the inflamed gastrointestinal tract. By identifying a large metabolic network characteristic of Salmonella serovars associated with gastroenteritis, our in silico analysis provides a blueprint for potential strategies to utilize inflammation-derived nutrients and edge out competing gut microbes.

  20. Genome-wide scan for signatures of human population differentiation and their relationship with natural selection, functional pathways and diseases.

    Directory of Open Access Journals (Sweden)

    Roberto Amato

    2009-11-01

    Full Text Available Genetic differences both between individuals and populations are studied for their evolutionary relevance and for their potential medical applications. Most of the genetic differentiation among populations are caused by random drift that should affect all loci across the genome in a similar manner. When a locus shows extraordinary high or low levels of population differentiation, this may be interpreted as evidence for natural selection. The most used measure of population differentiation was devised by Wright and is known as fixation index, or F(ST. We performed a genome-wide estimation of F(ST on about 4 millions of SNPs from HapMap project data. We demonstrated a heterogeneous distribution of F(ST values between autosomes and heterochromosomes. When we compared the F(ST values obtained in this study with another evolutionary measure obtained by comparative interspecific approach, we found that genes under positive selection appeared to show low levels of population differentiation. We applied a gene set approach, widely used for microarray data analysis, to detect functional pathways under selection. We found that one pathway related to antigen processing and presentation showed low levels of F(ST, while several pathways related to cell signalling, growth and morphogenesis showed high F(ST values. Finally, we detected a signature of selection within genes associated with human complex diseases. These results can help to identify which process occurred during human evolution and adaptation to different environments. They also support the hypothesis that common diseases could have a genetic background shaped by human evolution.

  1. Comparative genome analysis of trypanotolerance QTL

    African Journals Online (AJOL)

    GREGO

    2007-04-16

    Apr 16, 2007 ... homologous genes within the human genome were then identified and aligned to the bovine radiation hybrid map in order to identify the mouse/bovine homologous regions. This revealed homology between murine and bovine QTL on Tir3 while the region on Tir2 is linked to innate immune response.

  2. Comparative genomics of the Bifidobacterium breve taxon

    NARCIS (Netherlands)

    Bottacini, F.; O'Connell-Motherway, M.; Kuczynski, J.; O'Connell, K.J.; Serafini, F.; Duranti, S.; Milani, C.; Turroni, F.; Lugli, G.A.; Zomer, A.L.; Zhurina, D.; Riedel, C.; Ventura, M; Sinderen, D. van

    2014-01-01

    BACKGROUND: Bifidobacteria are commonly found as part of the microbiota of the gastrointestinal tract (GIT) of a broad range of hosts, where their presence is positively correlated with the host's health status. In this study, we assessed the genomes of thirteen representatives of Bifidobacterium

  3. Comparative genomics using data mining tools

    Indian Academy of Sciences (India)

    We have analysed the genomes of representatives of three kingdoms of life, namely, archaea, eubacteria and eukaryota using data mining tools based on compositional analyses of the protein sequences. The representatives chosen in this analysis were Methanococcus jannaschii, Haemophilus influenzae and ...

  4. Comparative genomics using data mining tools

    Indian Academy of Sciences (India)

    Unknown

    We have analysed the genomes of representatives of three kingdoms of life, namely, archaea, eubacteria and eukaryota using data mining tools based on compositional analyses of the protein sequences. The repre- sentatives chosen in this analysis were Methanococcus jannaschii, Haemophilus influenzae and ...

  5. Comparative genome analysis of trypanotolerance QTL | Nganga ...

    African Journals Online (AJOL)

    Homologous sequences were used in the definition of synteny relationships and subsequent identification of the shared disease response genes. The homologous genes within the human genome were then identified and aligned to the bovine radiation hybrid map in order to identify the mouse/bovine homologous regions.

  6. Preferential duplication of intermodular hub genes: an evolutionary signature in eukaryotes genome networks.

    Directory of Open Access Journals (Sweden)

    Ricardo M Ferreira

    Full Text Available Whole genome protein-protein association networks are not random and their topological properties stem from genome evolution mechanisms. In fact, more connected, but less clustered proteins are related to genes that, in general, present more paralogs as compared to other genes, indicating frequent previous gene duplication episodes. On the other hand, genes related to conserved biological functions present few or no paralogs and yield proteins that are highly connected and clustered. These general network characteristics must have an evolutionary explanation. Considering data from STRING database, we present here experimental evidence that, more than not being scale free, protein degree distributions of organisms present an increased probability for high degree nodes. Furthermore, based on this experimental evidence, we propose a simulation model for genome evolution, where genes in a network are either acquired de novo using a preferential attachment rule, or duplicated with a probability that linearly grows with gene degree and decreases with its clustering coefficient. For the first time a model yields results that simultaneously describe different topological distributions. Also, this model correctly predicts that, to produce protein-protein association networks with number of links and number of nodes in the observed range for Eukaryotes, it is necessary 90% of gene duplication and 10% of de novo gene acquisition. This scenario implies a universal mechanism for genome evolution.

  7. An environmental signature for 323 microbial genomes based on codon adaptation indices

    DEFF Research Database (Denmark)

    Willenbrock, Hanni; Friis, Carsten; Juncker, Agnieszka

    2006-01-01

    Background: Codon adaptation indices ( CAIs) represent an evolutionary strategy to modulate gene expression and have widely been used to predict potentially highly expressed genes within microbial genomes. Here, we evaluate and compare two very different methods for estimating CAI values, one......: The results and the approach described here may be used to acquire new knowledge regarding species lifestyle and to elucidate relationships between organisms that are far apart evolutionarily....

  8. Adult high-grade B-cell lymphoma with Burkitt lymphoma signature: genomic features and potential therapeutic targets.

    Science.gov (United States)

    Bouska, Alyssa; Bi, Chengfeng; Lone, Waseem; Zhang, Weiwei; Kedwaii, Ambreen; Heavican, Tayla; Lachel, Cynthia M; Yu, Jiayu; Ferro, Roberto; Eldorghamy, Nanees; Greiner, Timothy C; Vose, Julie; Weisenburger, Dennis D; Gascoyne, Randy D; Rosenwald, Andreas; Ott, German; Campo, Elias; Rimsza, Lisa M; Jaffe, Elaine S; Braziel, Rita M; Siebert, Reiner; Miles, Rodney R; Dave, Sandeep; Reddy, Anupama; Delabie, Jan; Staudt, Louis M; Song, Joo Y; McKeithan, Timothy W; Fu, Kai; Green, Michael; Chan, Wing C; Iqbal, Javeed

    2017-10-19

    The adult high-grade B-cell lymphomas sharing molecular features with Burkitt lymphoma (BL) are highly aggressive lymphomas with poor clinical outcome. High-resolution structural and functional genomic analysis of adult Burkitt lymphoma (BL) and high-grade B-cell lymphoma with BL gene signature (adult-molecularly defined BL [mBL]) revealed the MYC-ARF-p53 axis as the primary deregulated pathway. Adult-mBL had either unique or more frequent genomic aberrations (del13q14, del17p, gain8q24, and gain18q21) compared with pediatric-mBL, but shared commonly mutated genes. Mutations in genes promoting the tonic B-cell receptor (BCR)→PI3K pathway ( TCF3 and ID3 ) did not differ by age, whereas effectors of chronic BCR→NF-κB signaling were associated with adult-mBL. A subset of adult-mBL had BCL2 translocation and mutation and elevated BCL2 mRNA and protein expression, but had a mutation profile similar to mBL. These double-hit lymphomas may have arisen from a tumor precursor that acquired both BCL2 and MYC translocations and/or KMT2D ( MLL2 ) mutation. Gain/amplification of MIR17HG and its paralogue loci was observed in 50% of adult-mBL. In vitro studies suggested miR-17∼92 's role in constitutive activation of BCR signaling and sensitivity to ibrutinib. Overall integrative analysis identified an interrelated gene network affected by copy number and mutation, leading to disruption of the p53 pathway and the BCR→PI3K or NF-κB activation, which can be further exploited in vivo by small-molecule inhibitors for effective therapy in adult-mBL.

  9. Comparative genomics of the lactic acid bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rokhsar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J. -H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O' Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

    2006-06-01

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

  10. Comparative Genomic Analysis of Soybean Flowering Genes

    Science.gov (United States)

    Jung, Chol-Hee; Wong, Chui E.; Singh, Mohan B.; Bhalla, Prem L.

    2012-01-01

    Flowering is an important agronomic trait that determines crop yield. Soybean is a major oilseed legume crop used for human and animal feed. Legumes have unique vegetative and floral complexities. Our understanding of the molecular basis of flower initiation and development in legumes is limited. Here, we address this by using a computational approach to examine flowering regulatory genes in the soybean genome in comparison to the most studied model plant, Arabidopsis. For this comparison, a genome-wide analysis of orthologue groups was performed, followed by an in silico gene expression analysis of the identified soybean flowering genes. Phylogenetic analyses of the gene families highlighted the evolutionary relationships among these candidates. Our study identified key flowering genes in soybean and indicates that the vernalisation and the ambient-temperature pathways seem to be the most variant in soybean. A comparison of the orthologue groups containing flowering genes indicated that, on average, each Arabidopsis flowering gene has 2-3 orthologous copies in soybean. Our analysis highlighted that the CDF3, VRN1, SVP, AP3 and PIF3 genes are paralogue-rich genes in soybean. Furthermore, the genome mapping of the soybean flowering genes showed that these genes are scattered randomly across the genome. A paralogue comparison indicated that the soybean genes comprising the largest orthologue group are clustered in a 1.4 Mb region on chromosome 16 of soybean. Furthermore, a comparison with the undomesticated soybean (Glycine soja) revealed that there are hundreds of SNPs that are associated with putative soybean flowering genes and that there are structural variants that may affect the genes of the light-signalling and ambient-temperature pathways in soybean. Our study provides a framework for the soybean flowering pathway and insights into the relationship and evolution of flowering genes between a short-day soybean and the long-day plant, Arabidopsis. PMID:22679494

  11. Comparative Genomics and Transcriptomics of Propionibacterium acnes

    OpenAIRE

    Brzuszkiewicz, Elzbieta; Weiner, January; Wollherr, Antje; Thürmer, Andrea; Hüpeden, Jennifer; Lomholt, Hans B.; Kilian, Mogens; Gottschalk, Gerhard; Daniel, Rolf; Mollenkopf, Hans-Joachim; Meyer, Thomas F.; Brüggemann, Holger

    2011-01-01

    The anaerobic Gram-positive bacterium Propionibacterium acnes is a human skin commensal that is occasionally associated with inflammatory diseases. Recent work has indicated that evolutionary distinct lineages of P. acnes play etiologic roles in disease while others are associated with maintenance of skin homeostasis. To shed light on the molecular basis for differential strain properties, we carried out genomic and transcriptomic analysis of distinct P. acnes strains. We sequenced ...

  12. GenoSets: visual analytic methods for comparative genomics.

    Directory of Open Access Journals (Sweden)

    Aurora A Cain

    Full Text Available Many important questions in biology are, fundamentally, comparative, and this extends to our analysis of a growing number of sequenced genomes. Existing genomic analysis tools are often organized around literal views of genomes as linear strings. Even when information is highly condensed, these views grow cumbersome as larger numbers of genomes are added. Data aggregation and summarization methods from the field of visual analytics can provide abstracted comparative views, suitable for sifting large multi-genome datasets to identify critical similarities and differences. We introduce a software system for visual analysis of comparative genomics data. The system automates the process of data integration, and provides the analysis platform to identify and explore features of interest within these large datasets. GenoSets borrows techniques from business intelligence and visual analytics to provide a rich interface of interactive visualizations supported by a multi-dimensional data warehouse. In GenoSets, visual analytic approaches are used to enable querying based on orthology, functional assignment, and taxonomic or user-defined groupings of genomes. GenoSets links this information together with coordinated, interactive visualizations for both detailed and high-level categorical analysis of summarized data. GenoSets has been designed to simplify the exploration of multiple genome datasets and to facilitate reasoning about genomic comparisons. Case examples are included showing the use of this system in the analysis of 12 Brucella genomes. GenoSets software and the case study dataset are freely available at http://genosets.uncc.edu. We demonstrate that the integration of genomic data using a coordinated multiple view approach can simplify the exploration of large comparative genomic data sets, and facilitate reasoning about comparisons and features of interest.

  13. Complete Genome Sequence and Comparative Genomics of a Novel Myxobacterium Myxococcus hansupus.

    Directory of Open Access Journals (Sweden)

    Gaurav Sharma

    Full Text Available Myxobacteria, a group of Gram-negative aerobes, belong to the class δ-proteobacteria and order Myxococcales. Unlike anaerobic δ-proteobacteria, they exhibit several unusual physiogenomic properties like gliding motility, desiccation-resistant myxospores and large genomes with high coding density. Here we report a 9.5 Mbp complete genome of Myxococcus hansupus that encodes 7,753 proteins. Phylogenomic and genome-genome distance based analysis suggest that Myxococcus hansupus is a novel member of the genus Myxococcus. Comparative genome analysis with other members of the genus Myxococcus was performed to explore their genome diversity. The variation in number of unique proteins observed across different species is suggestive of diversity at the genus level while the overrepresentation of several Pfam families indicates the extent and mode of genome expansion as compared to non-Myxococcales δ-proteobacteria.

  14. Genome-wide profiling of pluripotent cells reveals a unique molecular signature of human embryonic germ cells.

    Directory of Open Access Journals (Sweden)

    Nikta Pashai

    Full Text Available Human embryonic germ cells (EGCs provide a powerful model for identifying molecules involved in the pluripotent state when compared to their progenitors, primordial germ cells (PGCs, and other pluripotent stem cells. Microarray and Principal Component Analysis (PCA reveals for the first time that human EGCs possess a transcription profile distinct from PGCs and other pluripotent stem cells. Validation with qRT-PCR confirms that human EGCs and PGCs express many pluripotency-associated genes but with quantifiable differences compared to pluripotent embryonic stem cells (ESCs, induced pluripotent stem cells (IPSCs, and embryonal carcinoma cells (ECCs. Analyses also identified a number of target genes that may be potentially associated with their unique pluripotent states. These include IPO7, MED7, RBM26, HSPD1, and KRAS which were upregulated in EGCs along with other pluripotent stem cells when compared to PGCs. Other potential target genes were also found which may contribute toward a primed ESC-like state. These genes were exclusively up-regulated in ESCs, IPSCs and ECCs including PARP1, CCNE1, CDK6, AURKA, MAD2L1, CCNG1, and CCNB1 which are involved in cell cycle regulation, cellular metabolism and DNA repair and replication. Gene classification analysis also confirmed that the distinguishing feature of EGCs compared to ESCs, ECCs, and IPSCs lies primarily in their genetic contribution to cellular metabolism, cell cycle, and cell adhesion. In contrast, several genes were found upregulated in PGCs which may help distinguish their unipotent state including HBA1, DMRT1, SPANXA1, and EHD2. Together, these findings provide the first glimpse into a unique genomic signature of human germ cells and pluripotent stem cells and provide genes potentially involved in defining different states of germ-line pluripotency.

  15. Genome-Wide Profiling of Pluripotent Cells Reveals a Unique Molecular Signature of Human Embryonic Germ Cells

    Science.gov (United States)

    Pashai, Nikta; Hao, Haiping; All, Angelo; Gupta, Siddharth; Chaerkady, Raghothama; De Los Angeles, Alejandro; Gearhart, John D.; Kerr, Candace L.

    2012-01-01

    Human embryonic germ cells (EGCs) provide a powerful model for identifying molecules involved in the pluripotent state when compared to their progenitors, primordial germ cells (PGCs), and other pluripotent stem cells. Microarray and Principal Component Analysis (PCA) reveals for the first time that human EGCs possess a transcription profile distinct from PGCs and other pluripotent stem cells. Validation with qRT-PCR confirms that human EGCs and PGCs express many pluripotency-associated genes but with quantifiable differences compared to pluripotent embryonic stem cells (ESCs), induced pluripotent stem cells (IPSCs), and embryonal carcinoma cells (ECCs). Analyses also identified a number of target genes that may be potentially associated with their unique pluripotent states. These include IPO7, MED7, RBM26, HSPD1, and KRAS which were upregulated in EGCs along with other pluripotent stem cells when compared to PGCs. Other potential target genes were also found which may contribute toward a primed ESC-like state. These genes were exclusively up-regulated in ESCs, IPSCs and ECCs including PARP1, CCNE1, CDK6, AURKA, MAD2L1, CCNG1, and CCNB1 which are involved in cell cycle regulation, cellular metabolism and DNA repair and replication. Gene classification analysis also confirmed that the distinguishing feature of EGCs compared to ESCs, ECCs, and IPSCs lies primarily in their genetic contribution to cellular metabolism, cell cycle, and cell adhesion. In contrast, several genes were found upregulated in PGCs which may help distinguish their unipotent state including HBA1, DMRT1, SPANXA1, and EHD2. Together, these findings provide the first glimpse into a unique genomic signature of human germ cells and pluripotent stem cells and provide genes potentially involved in defining different states of germ-line pluripotency. PMID:22737227

  16. Sinbase: an integrated database to study genomics, genetics and comparative genomics in Sesamum indicum.

    Science.gov (United States)

    Wang, Linhai; Yu, Jingyin; Li, Donghua; Zhang, Xiurong

    2015-01-01

    Sesame (Sesamum indicum L.) is an ancient and important oilseed crop grown widely in tropical and subtropical areas. It belongs to the gigantic order Lamiales, which includes many well-known or economically important species, such as olive (Olea europaea), leonurus (Leonurus japonicus) and lavender (Lavandula spica), many of which have important pharmacological properties. Despite their importance, genetic and genomic analyses on these species have been insufficient due to a lack of reference genome information. The now available S. indicum genome will provide an unprecedented opportunity for studying both S. indicum genetic traits and comparative genomics. To deliver S. indicum genomic information to the worldwide research community, we designed Sinbase, a web-based database with comprehensive sesame genomic, genetic and comparative genomic information. Sinbase includes sequences of assembled sesame pseudomolecular chromosomes, protein-coding genes (27,148), transposable elements (372,167) and non-coding RNAs (1,748). In particular, Sinbase provides unique and valuable information on colinear regions with various plant genomes, including Arabidopsis thaliana, Glycine max, Vitis vinifera and Solanum lycopersicum. Sinbase also provides a useful search function and data mining tools, including a keyword search and local BLAST service. Sinbase will be updated regularly with new features, improvements to genome annotation and new genomic sequences, and is freely accessible at http://ocri-genomics.org/Sinbase/. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. High resolution microarray comparative genomic hybridisation analysis using spotted oligonucleotides.

    NARCIS (Netherlands)

    Carvalho, B; Ouwerkerk, E; Meijer, G.A.; Ylstra, B.

    2004-01-01

    BACKGROUND: Currently, comparative genomic hybridisation array (array CGH) is the method of choice for studying genome wide DNA copy number changes. To date, either amplified representations of bacterial artificial chromosomes (BACs)/phage artificial chromosomes (PACs) or cDNAs have been spotted as

  18. Comparative genomic in situ hybridization analysis on the ...

    African Journals Online (AJOL)

    AJL

    2012-04-10

    Apr 10, 2012 ... Comparative genomic in situ hybridization analysis on the chromosomes of five grass species with rice genomic DNA probe. Chao-Wen She1,2*, Yun-Chun Song3 and Xiang-Hui Jiang1, 2. 1Department of Life Sciences, Huaihua University, No.612 Yingfeng East Road Huaihua 418008, Hunan, China.

  19. Genomic signatures of adaptation to wine biological ageing conditions in biofilm-forming flor yeasts.

    Science.gov (United States)

    Coi, A L; Bigey, F; Mallet, S; Marsit, S; Zara, G; Gladieux, P; Galeote, V; Budroni, M; Dequin, S; Legras, J L

    2017-04-01

    The molecular and evolutionary processes underlying fungal domestication remain largely unknown despite the importance of fungi to bioindustry and for comparative adaptation genomics in eukaryotes. Wine fermentation and biological ageing are performed by strains of S. cerevisiae with, respectively, pelagic fermentative growth on glucose and biofilm aerobic growth utilizing ethanol. Here, we use environmental samples of wine and flor yeasts to investigate the genomic basis of yeast adaptation to contrasted anthropogenic environments. Phylogenetic inference and population structure analysis based on single nucleotide polymorphisms revealed a group of flor yeasts separated from wine yeasts. A combination of methods revealed several highly differentiated regions between wine and flor yeasts, and analyses using codon-substitution models for detecting molecular adaptation identified sites under positive selection in the high-affinity transporter gene ZRT1. The cross-population composite likelihood ratio revealed selective sweeps at three regions, including in the hexose transporter gene HXT7, the yapsin gene YPS6 and the membrane protein coding gene MTS27. Our analyses also revealed that the biological ageing environment has led to the accumulation of numerous mutations in proteins from several networks, including Flo11 regulation and divalent metal transport. Together, our findings suggest that the tuning of FLO11 expression and zinc transport networks are a distinctive feature of the genetic changes underlying the domestication of flor yeasts. Our study highlights the multiplicity of genomic changes underlying yeast adaptation to man-made habitats and reveals that flor/wine yeast lineage can serve as a useful model for studying the genomics of adaptive divergence. © 2017 John Wiley & Sons Ltd.

  20. DNA Microarrays in Comparative Genomics and Transcriptomics

    DEFF Research Database (Denmark)

    Willenbrock, Hanni

    2007-01-01

    analysis, analysis of chromosomal aberrations and DNA sequence dependent gene expression. First, this thesis contains a description of how the gene expression profiles from children with acute lymphoblastic leukemia may be used to improve the diagnosis of these patients and potentially improve......During the past few years, innovations in the DNA sequencing technology has led to an explosion in available DNA sequence information. This has revolutionized biological research and promoted the development of high throughput analysis methods that can take advantage of the vast amount of sequence...... of each method’s ability to analyze DNA copy number data. Moreover, our study shows that analysis methods developed for cancer research may also successfully be applied to DNA copy number profiles from bacterial genomes. However, here the purpose is to characterize variations in the gene content...

  1. Enhanced annotations and features for comparing thousands of Pseudomonas genomes in the Pseudomonas genome database.

    Science.gov (United States)

    Winsor, Geoffrey L; Griffiths, Emma J; Lo, Raymond; Dhillon, Bhavjinder K; Shay, Julie A; Brinkman, Fiona S L

    2016-01-04

    The Pseudomonas Genome Database (http://www.pseudomonas.com) is well known for the application of community-based annotation approaches for producing a high-quality Pseudomonas aeruginosa PAO1 genome annotation, and facilitating whole-genome comparative analyses with other Pseudomonas strains. To aid analysis of potentially thousands of complete and draft genome assemblies, this database and analysis platform was upgraded to integrate curated genome annotations and isolate metadata with enhanced tools for larger scale comparative analysis and visualization. Manually curated gene annotations are supplemented with improved computational analyses that help identify putative drug targets and vaccine candidates or assist with evolutionary studies by identifying orthologs, pathogen-associated genes and genomic islands. The database schema has been updated to integrate isolate metadata that will facilitate more powerful analysis of genomes across datasets in the future. We continue to place an emphasis on providing high-quality updates to gene annotations through regular review of the scientific literature and using community-based approaches including a major new Pseudomonas community initiative for the assignment of high-quality gene ontology terms to genes. As we further expand from thousands of genomes, we plan to provide enhancements that will aid data visualization and analysis arising from whole-genome comparative studies including more pan-genome and population-based approaches. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Reference-Free Comparative Genomics of 174 Chloroplasts

    Science.gov (United States)

    Kua, Chai-Shian; Ruan, Jue; Harting, John; Ye, Cheng-Xi; Helmus, Matthew R.; Yu, Jun; Cannon, Charles H.

    2012-01-01

    Direct analysis of unassembled genomic data could greatly increase the power of short read DNA sequencing technologies and allow comparative genomics of organisms without a completed reference available. Here, we compare 174 chloroplasts by analyzing the taxanomic distribution of short kmers across genomes [1]. We then assemble de novo contigs centered on informative variation. The localized de novo contigs can be separated into two major classes: tip = unique to a single genome and group = shared by a subset of genomes. Prior to assembly, we found that ∼18% of the chloroplast was duplicated in the inverted repeat (IR) region across a four-fold difference in genome sizes, from a highly reduced parasitic orchid [2] to a massive algal chloroplast [3], including gnetophytes [4] and cycads [5]. The conservation of this ratio between single copy and duplicated sequence was basal among green plants, independent of photosynthesis and mechanism of genome size change, and different in gymnosperms and lower plants. Major lineages in the angiosperm clade differed in the pattern of shared kmers and de novo contigs. For example, parasitic plants demonstrated an expected accelerated overall rate of evolution, while the hemi-parasitic genomes contained a great deal more novel sequence than holo-parasitic plants, suggesting different mechanisms at different stages of genomic contraction. Additionally, the legumes are diverging more quickly and in different ways than other major families. Small duplicated fragments of the rrn23 genes were deeply conserved among seed plants, including among several species without the IR regions, indicating a crucial functional role of this duplication. Localized de novo assembly of informative kmers greatly reduces the complexity of large comparative analyses by confining the analysis to a small partition of data and genomes relevant to the specific question, allowing direct analysis of next-gen sequence data from previously unstudied

  3. Whole-genome sequencing of eight goat populations for the detection of selection signatures underlying production and adaptive traits

    Science.gov (United States)

    Wang, Xiaolong; Liu, Jing; Zhou, Guangxian; Guo, Jiazhong; Yan, Hailong; Niu, Yiyuan; Li, Yan; Yuan, Chao; Geng, Rongqing; Lan, Xianyong; An, Xiaopeng; Tian, Xingui; Zhou, Huangkai; Song, Jiuzhou; Jiang, Yu; Chen, Yulin

    2016-01-01

    The goat (Capra hircus) is one of the first farm animals that have undergone domestication and extensive natural and artificial selection by adapting to various environments, which in turn has resulted in its high level of phenotypic diversity. Here, we generated medium-coverage (9–13×) sequences from eight domesticated goat breeds, representing morphologically or geographically specific populations, to identify genomic regions representing selection signatures. We discovered ~10 million single nucleotide polymorphisms (SNPs) for each breed. By combining two approaches, ZHp and di values, we identified 22 genomic regions that may have contributed to the phenotypes in coat color patterns, body size, cashmere traits, as well as high altitude adaptation in goat populations. Candidate genes underlying strong selection signatures including coloration (ASIP, KITLG, HTT, GNA11, and OSTM1), body size (TBX15, DGCR8, CDC25A, and RDH16), cashmere traits (LHX2, FGF9, and WNT2), and hypoxia adaptation (CDK2, SOCS2, NOXA1, and ENPEP) were identified. We also identified candidate functional SNPs within selected genes that may be important for each trait. Our results demonstrated the potential of using sequence data in identifying genomic regions that are responsible for agriculturally significant phenotypes in goats, which in turn can be used in the selection of goat breeds for environmental adaptation and domestication. PMID:27941843

  4. Comparative analysis of the mitochondrial genomes in gastropods

    International Nuclear Information System (INIS)

    Arquez, Moises; Uribe, Juan Esteban; Castro, Lyda Raquel

    2012-01-01

    In this work we presented a comparative analysis of the mitochondrial genomes in gastropods. Nucleotide and amino acids composition was calculated and a comparative visual analysis of the start and termination codons was performed. The organization of the genome was compared calculating the number of intergenic sequences, the location of the genes and the number of reorganized genes (breakpoints) in comparison with the sequence that is presumed to be ancestral for the group. In order to calculate variations in the rates of molecular evolution within the group, the relative rate test was performed. In spite of the differences in the size of the genomes, the amino acids number is conserved. The nucleotide and amino acid composition is similar between Vetigastropoda, Ceanogastropoda and Neritimorpha in comparison to Heterobranchia and Patellogastropoda. The mitochondrial genomes of the group are very compact with few intergenic sequences, the only exception is the genome of Patellogastropoda with 26,828 bp. Start codons of the Heterobranchia and Patellogastropoda are very variable and there is also an increase in genome rearrangements for these two groups. Generally, the hypothesis of constant rates of molecular evolution between the groups is rejected, except when the genomes of Caenogastropoda and Vetigastropoda are compared.

  5. What constitutes an Arabian Helicobacter pylori? Lessons from comparative genomics.

    Science.gov (United States)

    Kumar, Narender; Albert, M John; Al Abkal, Hanan; Siddique, Iqbal; Ahmed, Niyaz

    2017-02-01

    Helicobacter pylori, the human gastric pathogen, causes a variety of gastric diseases ranging from mild gastritis to gastric cancer. While the studies on H. pylori are dominated by those based on either East Asian or Western strains, information regarding H. pylori strains prevalent in the Middle East remains scarce. Therefore, we carried out whole-genome sequencing and comparative analysis of three H. pylori strains isolated from three native Arab, Kuwaiti patients. H. pylori strains were sequenced using Illumina platform. The sequence reads were filtered and draft genomes were assembled and annotated. Various pathogenicity-associated regions and phages present within the genomes were identified. Phylogenetic analysis was carried out to determine the genetic relatedness of Kuwaiti strains to various lineages of H. pylori. The core genome content and virulence-related genes were analyzed to assess the pathogenic potential. The three genomes clustered along with HpEurope strains in the phylogenetic tree comprising various H. pylori lineages. A total of 1187 genes spread among various functional classes were identified in the core genome analysis. The three genomes possessed a complete cagPAI and also retained most of the known outer membrane proteins as well as virulence-related genes. The cagA gene in all three strains consisted of an AB-C type EPIYA motif. The comparative genomic analysis of Kuwaiti H. pylori strains revealed a European ancestry and a high pathogenic potential. © 2016 John Wiley & Sons Ltd.

  6. Big genomes facilitate the comparative identification of regulatory elements.

    Directory of Open Access Journals (Sweden)

    Brant K Peterson

    Full Text Available The identification of regulatory sequences in animal genomes remains a significant challenge. Comparative genomic methods that use patterns of evolutionary conservation to identify non-coding sequences with regulatory function have yielded many new vertebrate enhancers. However, these methods have not contributed significantly to the identification of regulatory sequences in sequenced invertebrate taxa. We demonstrate here that this differential success, which is often attributed to fundamental differences in the nature of vertebrate and invertebrate regulatory sequences, is instead primarily a product of the relatively small size of sequenced invertebrate genomes. We sequenced and compared loci involved in early embryonic patterning from four species of true fruit flies (family Tephritidae that have genomes four to six times larger than those of Drosophila melanogaster. Unlike in Drosophila, where virtually all non-coding DNA is highly conserved, blocks of conserved non-coding sequence in tephritids are flanked by large stretches of poorly conserved sequence, similar to what is observed in vertebrate genomes. We tested the activities of nine conserved non-coding sequences flanking the even-skipped gene of the teprhitid Ceratis capitata in transgenic D. melanogaster embryos, six of which drove patterns that recapitulate those of known D. melanogaster enhancers. In contrast, none of the three non-conserved tephritid non-coding sequences that we tested drove expression in D. melanogaster embryos. Based on the landscape of non-coding conservation in tephritids, and our initial success in using conservation in tephritids to identify D. melanogaster regulatory sequences, we suggest that comparison of tephritid genomes may provide a systematic means to annotate the non-coding portion of the D. melanogaster genome. We also propose that large genomes be given more consideration in the selection of species for comparative genomics projects, to provide

  7. Distinct signatures of diversifying selection revealed by genome analysis of respiratory tract and invasive bacterial populations.

    Science.gov (United States)

    Shea, Patrick R; Beres, Stephen B; Flores, Anthony R; Ewbank, Amy L; Gonzalez-Lugo, Javier H; Martagon-Rosado, Alexandro J; Martinez-Gutierrez, Juan C; Rehman, Hina A; Serrano-Gonzalez, Monica; Fittipaldi, Nahuel; Ayers, Stephen D; Webb, Paul; Willey, Barbara M; Low, Donald E; Musser, James M

    2011-03-22

    Many pathogens colonize different anatomical sites, but the selective pressures contributing to survival in the diverse niches are poorly understood. Group A Streptococcus (GAS) is a human-adapted bacterium that causes a range of infections. Much effort has been expended to dissect the molecular basis of invasive (sterile-site) infections, but little is known about the genomes of strains causing pharyngitis (streptococcal "sore throat"). Additionally, there is essentially nothing known about the genetic relationships between populations of invasive and pharyngitis strains. In particular, it is unclear if invasive strains represent a distinct genetic subpopulation of strains that cause pharyngitis. We compared the genomes of 86 serotype M3 GAS pharyngitis strains with those of 215 invasive M3 strains from the same geographical location. The pharyngitis and invasive groups were highly related to each other and had virtually identical phylogenetic structures, indicating they belong to the same genetic pool. Despite the overall high degree of genetic similarity, we discovered that strains from different host environments (i.e., throat, normally sterile sites) have distinct patterns of diversifying selection at the nucleotide level. In particular, the pattern of polymorphisms in the hyaluronic acid capsule synthesis operon was especially different between the two strain populations. This finding was mirrored by data obtained from full-genome analysis of strains sequentially cultured from nonhuman primates. Our results answer the long-standing question of the genetic relationship between GAS pharyngitis and invasive strains. The data provide previously undescribed information about the evolutionary history of pathogenic microbes that cause disease in different anatomical sites.

  8. Whole-Genome DNA Methylation Profiling Identifies Epigenetic Signatures of Uterine Carcinosarcoma.

    Science.gov (United States)

    Li, Jing; Xing, Xiaoyun; Li, Daofeng; Zhang, Bo; Mutch, David G; Hagemann, Ian S; Wang, Ting

    2017-02-01

    Uterine carcinosarcoma (UCS) is a form of endometrial cancer simultaneously exhibiting carcinomatous and sarcomatous elements, but the underlying molecular and epigenetic basis of this disease is poorly understood. We generated complete DNA methylomes for both the carcinomatous and the sarcomatous components of three UCS samples separated by laser capture microdissection and compared DNA methylomes of UCS with those of normal endometrium as well as methylomes derived from endometrioid carcinoma, serous endometrial carcinoma, and endometrial stromal sarcoma. We identified epigenetic lesions specific to carcinosarcoma and specific to its two components. Hallmarks of DNA methylation abnormalities in UCS included global hypomethylation, especially in repetitive elements, and hypermethylation of tumor suppressor gene promoters. Among these, aberrant DNA methylation of MIR200 genes is a key feature of UCS. The carcinoma component of UCS was characterized by hypermethylation of promoters of EMILIN1, NEFM, and CLEC14A, genes that are associated with tumor vascularization. In contrast, DNA methylation changes of PKP3, FAM83F, and TCP11 were more characteristic of the sarcoma components. Our findings highlight the epigenetic signatures that distinguish the two components of UCS, providing a valuable resource for investigation of this disease. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Whole-Genome DNA Methylation Profiling Identifies Epigenetic Signatures of Uterine Carcinosarcoma

    Directory of Open Access Journals (Sweden)

    Jing Li

    2017-02-01

    Full Text Available Uterine carcinosarcoma (UCS is a form of endometrial cancer simultaneously exhibiting carcinomatous and sarcomatous elements, but the underlying molecular and epigenetic basis of this disease is poorly understood. We generated complete DNA methylomes for both the carcinomatous and the sarcomatous components of three UCS samples separated by laser capture microdissection and compared DNA methylomes of UCS with those of normal endometrium as well as methylomes derived from endometrioid carcinoma, serous endometrial carcinoma, and endometrial stromal sarcoma. We identified epigenetic lesions specific to carcinosarcoma and specific to its two components. Hallmarks of DNA methylation abnormalities in UCS included global hypomethylation, especially in repetitive elements, and hypermethylation of tumor suppressor gene promoters. Among these, aberrant DNA methylation of MIR200 genes is a key feature of UCS. The carcinoma component of UCS was characterized by hypermethylation of promoters of EMILIN1, NEFM, and CLEC14A, genes that are associated with tumor vascularization. In contrast, DNA methylation changes of PKP3, FAM83F, and TCP11 were more characteristic of the sarcoma components. Our findings highlight the epigenetic signatures that distinguish the two components of UCS, providing a valuable resource for investigation of this disease.

  10. Comparative Genomics Reveals Accelerated Evolution in Conserved Pathways during the Diversification of Anole Lizards

    Science.gov (United States)

    Tollis, Marc; Hutchins, Elizabeth D; Stapley, Jessica; Rupp, Shawn M; Eckalbar, Walter L; Maayan, Inbar; Lasku, Eris; Infante, Carlos R; Dennis, Stuart R; Robertson, Joel A; May, Catherine M; Bermingham, Eldredge; DeNardo, Dale F; Hsieh, Shi-Tong Tonia; Kulathinal, Rob J; McMillan, William Owen; Menke, Douglas B; Pratt, Stephen C; Rawls, Jeffery Alan; Sanjur, Oris; Wilson-Rawls, Jeanne; Wilson Sayres, Melissa A; Fisher, Rebecca E

    2018-01-01

    Abstract Squamates include all lizards and snakes, and display some of the most diverse and extreme morphological adaptations among vertebrates. However, compared with birds and mammals, relatively few resources exist for comparative genomic analyses of squamates, hampering efforts to understand the molecular bases of phenotypic diversification in such a speciose clade. In particular, the ∼400 species of anole lizard represent an extensive squamate radiation. Here, we sequence and assemble the draft genomes of three anole species—Anolis frenatus, Anolis auratus, and Anolis apletophallus—for comparison with the available reference genome of Anolis carolinensis. Comparative analyses reveal a rapid background rate of molecular evolution consistent with a model of punctuated equilibrium, and strong purifying selection on functional genomic elements in anoles. We find evidence for accelerated evolution in genes involved in behavior, sensory perception, and reproduction, as well as in genes regulating limb bud development and hindlimb specification. Morphometric analyses of anole fore and hindlimbs corroborated these findings. We detect signatures of positive selection across several genes related to the development and regulation of the forebrain, hormones, and the iguanian lizard dewlap, suggesting molecular changes underlying behavioral adaptations known to reinforce species boundaries were a key component in the diversification of anole lizards. PMID:29360978

  11. Comparative analysis of prophages in Streptococcus mutans genomes

    Science.gov (United States)

    Fu, Tiwei; Fan, Xiangyu; Long, Quanxin; Deng, Wanyan; Song, Jinlin

    2017-01-01

    Prophages have been considered genetic units that have an intimate association with novel phenotypic properties of bacterial hosts, such as pathogenicity and genomic variation. Little is known about the genetic information of prophages in the genome of Streptococcus mutans, a major pathogen of human dental caries. In this study, we identified 35 prophage-like elements in S. mutans genomes and performed a comparative genomic analysis. Comparative genomic and phylogenetic analyses of prophage sequences revealed that the prophages could be classified into three main large clusters: Cluster A, Cluster B, and Cluster C. The S. mutans prophages in each cluster were compared. The genomic sequences of phismuN66-1, phismuNLML9-1, and phismu24-1 all shared similarities with the previously reported S. mutans phages M102, M102AD, and ϕAPCM01. The genomes were organized into seven major gene clusters according to the putative functions of the predicted open reading frames: packaging and structural modules, integrase, host lysis modules, DNA replication/recombination modules, transcriptional regulatory modules, other protein modules, and hypothetical protein modules. Moreover, an integrase gene was only identified in phismuNLML9-1 prophages. PMID:29158986

  12. Detection of selection signatures of population-specific genomic regions selected during domestication process in Jinhua pigs.

    Science.gov (United States)

    Li, Zhengcao; Chen, Jiucheng; Wang, Zhen; Pan, Yuchun; Wang, Qishan; Xu, Ningying; Wang, Zhengguang

    2016-12-01

    Chinese pigs have been undergoing both natural and artificial selection for thousands of years. Jinhua pigs are of great importance, as they can be a valuable model for exploring the genetic mechanisms linked to meat quality and other traits such as disease resistance, reproduction and production. The purpose of this study was to identify distinctive footprints of selection between Jinhua pigs and other breeds utilizing genome-wide SNP data. Genotyping by genome reducing and sequencing was implemented in order to perform cross-population extended haplotype homozygosity to reveal strong signatures of selection for those economically important traits. This work was performed at a 2% genome level, which comprised 152 006 SNPs genotyped in a total of 517 individuals. Population-specific footprints of selective sweeps were searched for in the genome of Jinhua pigs using six native breeds and three European breeds as reference groups. Several candidate genes associated with meat quality, health and reproduction, such as GH1, CRHR2, TRAF4 and CCK, were found to be overlapping with the significantly positive outliers. Additionally, the results revealed that some genomic regions associated with meat quality, immune response and reproduction in Jinhua pigs have evolved directionally under domestication and subsequent selections. The identified genes and biological pathways in Jinhua pigs showed different selection patterns in comparison with the Chinese and European breeds. © 2016 Stichting International Foundation for Animal Genetics.

  13. De novo likelihood-based measures for comparing genome assemblies.

    Science.gov (United States)

    Ghodsi, Mohammadreza; Hill, Christopher M; Astrovskaya, Irina; Lin, Henry; Sommer, Dan D; Koren, Sergey; Pop, Mihai

    2013-08-22

    The current revolution in genomics has been made possible by software tools called genome assemblers, which stitch together DNA fragments "read" by sequencing machines into complete or nearly complete genome sequences. Despite decades of research in this field and the development of dozens of genome assemblers, assessing and comparing the quality of assembled genome sequences still relies on the availability of independently determined standards, such as manually curated genome sequences, or independently produced mapping data. These "gold standards" can be expensive to produce and may only cover a small fraction of the genome, which limits their applicability to newly generated genome sequences. Here we introduce a de novo  probabilistic measure of assembly quality which allows for an objective comparison of multiple assemblies generated from the same set of reads. We define the quality of a sequence produced by an assembler as the conditional probability of observing the sequenced reads from the assembled sequence. A key property of our metric is that the true genome sequence maximizes the score, unlike other commonly used metrics. We demonstrate that our de novo  score can be computed quickly and accurately in a practical setting even for large datasets, by estimating the score from a relatively small sample of the reads. To demonstrate the benefits of our score, we measure the quality of the assemblies generated in the GAGE and Assemblathon 1 assembly "bake-offs" with our metric. Even without knowledge of the true reference sequence, our de novo  metric closely matches the reference-based evaluation metrics used in the studies and outperforms other de novo  metrics traditionally used to measure assembly quality (such as N50). Finally, we highlight the application of our score to optimize assembly parameters used in genome assemblers, which enables better assemblies to be produced, even without prior knowledge of the genome being assembled. Likelihood

  14. SNUGB: a versatile genome browser supporting comparative and functional fungal genomics

    Directory of Open Access Journals (Sweden)

    Kim Seungill

    2008-12-01

    Full Text Available Abstract Background Since the full genome sequences of Saccharomyces cerevisiae were released in 1996, genome sequences of over 90 fungal species have become publicly available. The heterogeneous formats of genome sequences archived in different sequencing centers hampered the integration of the data for efficient and comprehensive comparative analyses. The Comparative Fungal Genomics Platform (CFGP was developed to archive these data via a single standardized format that can support multifaceted and integrated analyses of the data. To facilitate efficient data visualization and utilization within and across species based on the architecture of CFGP and associated databases, a new genome browser was needed. Results The Seoul National University Genome Browser (SNUGB integrates various types of genomic information derived from 98 fungal/oomycete (137 datasets and 34 plant and animal (38 datasets species, graphically presents germane features and properties of each genome, and supports comparison between genomes. The SNUGB provides three different forms of the data presentation interface, including diagram, table, and text, and six different display options to support visualization and utilization of the stored information. Information for individual species can be quickly accessed via a new tool named the taxonomy browser. In addition, SNUGB offers four useful data annotation/analysis functions, including 'BLAST annotation.' The modular design of SNUGB makes its adoption to support other comparative genomic platforms easy and facilitates continuous expansion. Conclusion The SNUGB serves as a powerful platform supporting comparative and functional genomics within the fungal kingdom and also across other kingdoms. All data and functions are available at the web site http://genomebrowser.snu.ac.kr/.

  15. Comparative Analysis of the First Complete Enterococcus faecium Genome

    Science.gov (United States)

    Lam, Margaret M. C.; Seemann, Torsten; Bulach, Dieter M.; Gladman, Simon L.; Chen, Honglei; Haring, Volker; Moore, Robert J.; Ballard, Susan; Grayson, M. Lindsay; Johnson, Paul D. R.; Howden, Benjamin P.

    2012-01-01

    Vancomycin-resistant enterococci (VRE) are one of the leading causes of nosocomial infections in health care facilities around the globe. In particular, infections caused by vancomycin-resistant Enterococcus faecium are becoming increasingly common. Comparative and functional genomic studies of E. faecium isolates have so far been limited owing to the lack of a fully assembled E. faecium genome sequence. Here we address this issue and report the complete 3.0-Mb genome sequence of the multilocus sequence type 17 vancomycin-resistant Enterococcus faecium strain Aus0004, isolated from the bloodstream of a patient in Melbourne, Australia, in 1998. The genome comprises a 2.9-Mb circular chromosome and three circular plasmids. The chromosome harbors putative E. faecium virulence factors such as enterococcal surface protein, hemolysin, and collagen-binding adhesin. Aus0004 has a very large accessory genome (38%) that includes three prophage and two genomic islands absent among 22 other E. faecium genomes. One of the prophage was present as inverted 50-kb repeats that appear to have facilitated a 683-kb chromosomal inversion across the replication terminus, resulting in a striking replichore imbalance. Other distinctive features include 76 insertion sequence elements and a single chromosomal copy of Tn1549 containing the vanB vancomycin resistance element. A complete E. faecium genome will be a useful resource to assist our understanding of this emerging nosocomial pathogen. PMID:22366422

  16. PSAT: A web tool to compare genomic neighborhoods of multiple prokaryotic genomes

    Directory of Open Access Journals (Sweden)

    Wasnick Michael

    2008-03-01

    Full Text Available Abstract Background The conservation of gene order among prokaryotic genomes can provide valuable insight into gene function, protein interactions, or events by which genomes have evolved. Although some tools are available for visualizing and comparing the order of genes between genomes of study, few support an efficient and organized analysis between large numbers of genomes. The Prokaryotic Sequence homology Analysis Tool (PSAT is a web tool for comparing gene neighborhoods among multiple prokaryotic genomes. Results PSAT utilizes a database that is preloaded with gene annotation, BLAST hit results, and gene-clustering scores designed to help identify regions of conserved gene order. Researchers use the PSAT web interface to find a gene of interest in a reference genome and efficiently retrieve the sequence homologs found in other bacterial genomes. The tool generates a graphic of the genomic neighborhood surrounding the selected gene and the corresponding regions for its homologs in each comparison genome. Homologs in each region are color coded to assist users with analyzing gene order among various genomes. In contrast to common comparative analysis methods that filter sequence homolog data based on alignment score cutoffs, PSAT leverages gene context information for homologs, including those with weak alignment scores, enabling a more sensitive analysis. Features for constraining or ordering results are designed to help researchers browse results from large numbers of comparison genomes in an organized manner. PSAT has been demonstrated to be useful for helping to identify gene orthologs and potential functional gene clusters, and detecting genome modifications that may result in loss of function. Conclusion PSAT allows researchers to investigate the order of genes within local genomic neighborhoods of multiple genomes. A PSAT web server for public use is available for performing analyses on a growing set of reference genomes through any

  17. Comparative Genomics of a Parthenogenesis-Inducing Wolbachia Symbiont

    Science.gov (United States)

    Lindsey, Amelia R. I.; Werren, John H.; Richards, Stephen; Stouthamer, Richard

    2016-01-01

    Wolbachia is an intracellular symbiont of invertebrates responsible for inducing a wide variety of phenotypes in its host. These host-Wolbachia relationships span the continuum from reproductive parasitism to obligate mutualism, and provide a unique system to study genomic changes associated with the evolution of symbiosis. We present the genome sequence from a parthenogenesis-inducing Wolbachia strain (wTpre) infecting the minute parasitoid wasp Trichogramma pretiosum. The wTpre genome is the most complete parthenogenesis-inducing Wolbachia genome available to date. We used comparative genomics across 16 Wolbachia strains, representing five supergroups, to identify a core Wolbachia genome of 496 sets of orthologous genes. Only 14 of these sets are unique to Wolbachia when compared to other bacteria from the Rickettsiales. We show that the B supergroup of Wolbachia, of which wTpre is a member, contains a significantly higher number of ankyrin repeat-containing genes than other supergroups. In the wTpre genome, there is evidence for truncation of the protein coding sequences in 20% of ORFs, mostly as a result of frameshift mutations. The wTpre strain represents a conversion from cytoplasmic incompatibility to a parthenogenesis-inducing lifestyle, and is required for reproduction in the Trichogramma host it infects. We hypothesize that the large number of coding frame truncations has accompanied the change in reproductive mode of the wTpre strain. PMID:27194801

  18. Comparative Genomics of a Parthenogenesis-Inducing Wolbachia Symbiont.

    Science.gov (United States)

    Lindsey, Amelia R I; Werren, John H; Richards, Stephen; Stouthamer, Richard

    2016-07-07

    Wolbachia is an intracellular symbiont of invertebrates responsible for inducing a wide variety of phenotypes in its host. These host-Wolbachia relationships span the continuum from reproductive parasitism to obligate mutualism, and provide a unique system to study genomic changes associated with the evolution of symbiosis. We present the genome sequence from a parthenogenesis-inducing Wolbachia strain (wTpre) infecting the minute parasitoid wasp Trichogramma pretiosum The wTpre genome is the most complete parthenogenesis-inducing Wolbachia genome available to date. We used comparative genomics across 16 Wolbachia strains, representing five supergroups, to identify a core Wolbachia genome of 496 sets of orthologous genes. Only 14 of these sets are unique to Wolbachia when compared to other bacteria from the Rickettsiales. We show that the B supergroup of Wolbachia, of which wTpre is a member, contains a significantly higher number of ankyrin repeat-containing genes than other supergroups. In the wTpre genome, there is evidence for truncation of the protein coding sequences in 20% of ORFs, mostly as a result of frameshift mutations. The wTpre strain represents a conversion from cytoplasmic incompatibility to a parthenogenesis-inducing lifestyle, and is required for reproduction in the Trichogramma host it infects. We hypothesize that the large number of coding frame truncations has accompanied the change in reproductive mode of the wTpre strain. Copyright © 2016 Lindsey et al.

  19. Comparative Genomics of a Parthenogenesis-Inducing Wolbachia Symbiont

    Directory of Open Access Journals (Sweden)

    Amelia R. I. Lindsey

    2016-07-01

    Full Text Available Wolbachia is an intracellular symbiont of invertebrates responsible for inducing a wide variety of phenotypes in its host. These host-Wolbachia relationships span the continuum from reproductive parasitism to obligate mutualism, and provide a unique system to study genomic changes associated with the evolution of symbiosis. We present the genome sequence from a parthenogenesis-inducing Wolbachia strain (wTpre infecting the minute parasitoid wasp Trichogramma pretiosum. The wTpre genome is the most complete parthenogenesis-inducing Wolbachia genome available to date. We used comparative genomics across 16 Wolbachia strains, representing five supergroups, to identify a core Wolbachia genome of 496 sets of orthologous genes. Only 14 of these sets are unique to Wolbachia when compared to other bacteria from the Rickettsiales. We show that the B supergroup of Wolbachia, of which wTpre is a member, contains a significantly higher number of ankyrin repeat-containing genes than other supergroups. In the wTpre genome, there is evidence for truncation of the protein coding sequences in 20% of ORFs, mostly as a result of frameshift mutations. The wTpre strain represents a conversion from cytoplasmic incompatibility to a parthenogenesis-inducing lifestyle, and is required for reproduction in the Trichogramma host it infects. We hypothesize that the large number of coding frame truncations has accompanied the change in reproductive mode of the wTpre strain.

  20. Comparative genomics of vesicomyid clam (Bivalvia: Mollusca chemosynthetic symbionts

    Directory of Open Access Journals (Sweden)

    Girguis Peter R

    2008-12-01

    Full Text Available Abstract Background The Vesicomyidae (Bivalvia: Mollusca are a family of clams that form symbioses with chemosynthetic gamma-proteobacteria. They exist in environments such as hydrothermal vents and cold seeps and have a reduced gut and feeding groove, indicating a large dependence on their endosymbionts for nutrition. Recently, two vesicomyid symbiont genomes were sequenced, illuminating the possible nutritional contributions of the symbiont to the host and making genome-wide evolutionary analyses possible. Results To examine the genomic evolution of the vesicomyid symbionts, a comparative genomics framework, including the existing genomic data combined with heterologous microarray hybridization results, was used to analyze conserved gene content in four vesicomyid symbiont genomes. These four symbionts were chosen to include a broad phylogenetic sampling of the vesicomyid symbionts and represent distinct chemosynthetic environments: cold seeps and hydrothermal vents. Conclusion The results of this comparative genomics analysis emphasize the importance of the symbionts' chemoautotrophic metabolism within their hosts. The fact that these symbionts appear to be metabolically capable autotrophs underscores the extent to which the host depends on them for nutrition and reveals the key to invertebrate colonization of these challenging environments.

  1. Genomic signatures of near-extinction and rebirth of the crested ibis and other endangered bird species

    DEFF Research Database (Denmark)

    Li, Shengbin; Li, Bo; Cheng, Cheng

    2014-01-01

    BackgroundNearly a quarter of all avian species is either threatened or nearly threatened. Of these, 73 species are currently being rescued from going extinct in wildlife sanctuaries. One of the previously most critically-endangered is the crested ibis, Nipponia nippon. Once widespread across North...... of near extinction events in association with environmental and behavioral attributes of species. We confirm that both loss of genetic diversity and enrichment of deleterious mutations of protein-coding genes contribute to the major genetic defects of the endangered species. We further identify...... practices, to facilitate sustainable recovery of endangered species.ConclusionsThese findings demonstrate common genomic signatures of population decline across avian species and pave a way for further effort in saving endangered species and enhancing conservation genomic efforts....

  2. Sputnik: a database platform for comparative plant genomics.

    Science.gov (United States)

    Rudd, Stephen; Mewes, Hans-Werner; Mayer, Klaus F X

    2003-01-01

    Two million plant ESTs, from 20 different plant species, and totalling more than one 1000 Mbp of DNA sequence, represents a formidable transcriptomic resource. Sputnik uses the potential of this sequence resource to fill some of the information gap in the un-sequenced plant genomes and to serve as the foundation for in silicio comparative plant genomics. The complexity of the individual EST collections has been reduced using optimised EST clustering techniques. Annotation of cluster sequences is performed by exploiting and transferring information from the comprehensive knowledgebase already produced for the completed model plant genome (Arabidopsis thaliana) and by performing additional state of-the-art sequence analyses relevant to today's plant biologist. Functional predictions, comparative analyses and associative annotations for 500 000 plant EST derived peptides make Sputnik (http://mips.gsf.de/proj/sputnik/) a valid platform for contemporary plant genomics.

  3. The Perennial Ryegrass GenomeZipper – Targeted Use of Genome Resources for Comparative Grass Genomics

    DEFF Research Database (Denmark)

    Pfeiffer, Matthias; Martis, Mihaela; Asp, Torben

    2013-01-01

    Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass (Lo...

  4. Gramene 2016: comparative plant genomics and pathway resources.

    Science.gov (United States)

    Tello-Ruiz, Marcela K; Stein, Joshua; Wei, Sharon; Preece, Justin; Olson, Andrew; Naithani, Sushma; Amarasinghe, Vindhya; Dharmawardhana, Palitha; Jiao, Yinping; Mulvaney, Joseph; Kumari, Sunita; Chougule, Kapeel; Elser, Justin; Wang, Bo; Thomason, James; Bolser, Daniel M; Kerhornou, Arnaud; Walts, Brandon; Fonseca, Nuno A; Huerta, Laura; Keays, Maria; Tang, Y Amy; Parkinson, Helen; Fabregat, Antonio; McKay, Sheldon; Weiser, Joel; D'Eustachio, Peter; Stein, Lincoln; Petryszak, Robert; Kersey, Paul J; Jaiswal, Pankaj; Ware, Doreen

    2016-01-04

    Gramene (http://www.gramene.org) is an online resource for comparative functional genomics in crops and model plant species. Its two main frameworks are genomes (collaboration with Ensembl Plants) and pathways (The Plant Reactome and archival BioCyc databases). Since our last NAR update, the database website adopted a new Drupal management platform. The genomes section features 39 fully assembled reference genomes that are integrated using ontology-based annotation and comparative analyses, and accessed through both visual and programmatic interfaces. Additional community data, such as genetic variation, expression and methylation, are also mapped for a subset of genomes. The Plant Reactome pathway portal (http://plantreactome.gramene.org) provides a reference resource for analyzing plant metabolic and regulatory pathways. In addition to ∼ 200 curated rice reference pathways, the portal hosts gene homology-based pathway projections for 33 plant species. Both the genome and pathway browsers interface with the EMBL-EBI's Expression Atlas to enable the projection of baseline and differential expression data from curated expression studies in plants. Gramene's archive website (http://archive.gramene.org) continues to provide previously reported resources on comparative maps, markers and QTL. To further aid our users, we have also introduced a live monthly educational webinar series and a Gramene YouTube channel carrying video tutorials. Published by Oxford University Press on behalf of Nucleic Acids Research 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  5. Comparative Genome Analysis of Basidiomycete Fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert; Salamov, Asaf; Morin, Emmanuelle; Nagy, Laszlo; Manning, Gerard; Baker, Scott; Brown, Daren; Henrissat, Bernard; Levasseur, Anthony; Hibbett, David; Martin, Francis; Grigoriev, Igor

    2012-03-19

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, symbionts, and plant and animal pathogens. To better understand the diversity of phenotypes in basidiomycetes, we performed a comparative analysis of 35 basidiomycete fungi spanning the diversity of the phylum. Phylogenetic patterns of lignocellulose degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay. Patterns of secondary metabolic enzymes give additional insight into the broad array of phenotypes found in the basidiomycetes. We suggest that the profile of an organism in lignocellulose-targeting genes can be used to predict its nutritional mode, and predict Dacryopinax sp. as a brown rot; Botryobasidium botryosum and Jaapia argillacea as white rots.

  6. Comparative Genomic Analysis Identifies a Campylobacter Clade Deficient in Selenium Metabolism.

    Science.gov (United States)

    Miller, William G; Yee, Emma; Lopes, Bruno S; Chapman, Mary H; Huynh, Steven; Bono, James L; Parker, Craig T; Strachan, Norval J C; Forbes, Ken J

    2017-07-01

    The nonthermotolerant Campylobacter species C. fetus, C. hyointestinalis, C. iguaniorum, and C. lanienae form a distinct phylogenetic cluster within the genus. These species are primarily isolated from foraging (swine) or grazing (e.g., cattle, sheep) animals and cause sporadic and infrequent human illness. Previous typing studies identified three putative novel C. lanienae-related taxa, based on either MLST or atpA sequence data. To further characterize these putative novel taxa and the C. fetus group as a whole, 76 genomes were sequenced, either to completion or to draft level. These genomes represent 26 C. lanienae strains and 50 strains of the three novel taxa. C. fetus, C. hyointestinalis and C. iguaniorum genomes were previously sequenced to completion; therefore, a comparative genomic analysis across the entire C. fetus group was conducted (including average nucleotide identity analysis) that supports the initial identification of these three novel Campylobacter species. Furthermore, C. lanienae and the three putative novel species form a discrete clade within the C. fetus group, which we have termed the C. lanienae clade. This clade is distinguished from other members of the C. fetus group by a reduced genome size and distinct CRISPR/Cas systems. Moreover, there are two signature characteristics of the C. lanienae clade. C. lanienae clade genomes carry four to ten unlinked and similar, but nonidentical, flagellin genes. Additionally, all 76 C. lanienae clade genomes sequenced demonstrate a complete absence of genes related to selenium metabolism, including genes encoding the selenocysteine insertion machinery, selenoproteins, and the selenocysteinyl tRNA. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution 2017. This work is written by US Government employees and is in the public domain in the US.

  7. The genomic signature of sexual selection in the genetic diversity of the sex chromosomes and autosomes.

    Science.gov (United States)

    Corl, Ammon; Ellegren, Hans

    2012-07-01

    Genomic levels of variation can help reveal the selective and demographic forces that have affected a species during its history. The relative amount of genetic diversity observed on the sex chromosomes as compared to the autosomes is predicted to differ among monogamous and polygynous species. Many species show departures from the expectation for monogamy, but it can be difficult to conclude that this pattern results from variation in mating system because forces other than sexual selection can act upon sex chromosome genetic diversity. As a critical test of the role of mating system, we compared levels of genetic diversity on the Z chromosome and autosomes of phylogenetically independent pairs of shorebirds that differed in their mating systems. We found general support for sexual selection shaping sex chromosome diversity because most polygynous species showed relatively reduced genetic variation on their Z chromosomes as compared to monogamous species. Differences in levels of genetic diversity between the sex chromosomes and autosomes may therefore contribute to understanding the long-term history of sexual selection experienced by a species. © 2012 The Author(s).

  8. CloVR-Comparative: automated, cloud-enabled comparative microbial genome sequence analysis pipeline.

    Science.gov (United States)

    Agrawal, Sonia; Arze, Cesar; Adkins, Ricky S; Crabtree, Jonathan; Riley, David; Vangala, Mahesh; Galens, Kevin; Fraser, Claire M; Tettelin, Hervé; White, Owen; Angiuoli, Samuel V; Mahurkar, Anup; Fricke, W Florian

    2017-04-27

    The benefit of increasing genomic sequence data to the scientific community depends on easy-to-use, scalable bioinformatics support. CloVR-Comparative combines commonly used bioinformatics tools into an intuitive, automated, and cloud-enabled analysis pipeline for comparative microbial genomics. CloVR-Comparative runs on annotated complete or draft genome sequences that are uploaded by the user or selected via a taxonomic tree-based user interface and downloaded from NCBI. CloVR-Comparative runs reference-free multiple whole-genome alignments to determine unique, shared and core coding sequences (CDSs) and single nucleotide polymorphisms (SNPs). Output includes short summary reports and detailed text-based results files, graphical visualizations (phylogenetic trees, circular figures), and a database file linked to the Sybil comparative genome browser. Data up- and download, pipeline configuration and monitoring, and access to Sybil are managed through CloVR-Comparative web interface. CloVR-Comparative and Sybil are distributed as part of the CloVR virtual appliance, which runs on local computers or the Amazon EC2 cloud. Representative datasets (e.g. 40 draft and complete Escherichia coli genomes) are processed in <36 h on a local desktop or at a cost of <$20 on EC2. CloVR-Comparative allows anybody with Internet access to run comparative genomics projects, while eliminating the need for on-site computational resources and expertise.

  9. Chromosome-scale comparative sequence analysis unravels molecular mechanisms of genome evolution between two wheat cultivars

    KAUST Repository

    Thind, Anupriya Kaur

    2018-02-08

    Background: Recent improvements in DNA sequencing and genome scaffolding have paved the way to generate high-quality de novo assemblies of pseudomolecules representing complete chromosomes of wheat and its wild relatives. These assemblies form the basis to compare the evolutionary dynamics of wheat genomes on a megabase-scale. Results: Here, we provide a comparative sequence analysis of the 700-megabase chromosome 2D between two bread wheat genotypes, the old landrace Chinese Spring and the elite Swiss spring wheat line CH Campala Lr22a. There was a high degree of sequence conservation between the two chromosomes. Analysis of large structural variations revealed four large insertions/deletions (InDels) of >100 kb. Based on the molecular signatures at the breakpoints, unequal crossing over and double-strand break repair were identified as the evolutionary mechanisms that caused these InDels. Three of the large InDels affected copy number of NLRs, a gene family involved in plant immunity. Analysis of single nucleotide polymorphism (SNP) density revealed three haploblocks of 8 Mb, 9 Mb and 48 Mb with a 35-fold increased SNP density compared to the rest of the chromosome. Conclusions: This comparative analysis of two high-quality chromosome assemblies enabled a comprehensive assessment of large structural variations. The insight obtained from this analysis will form the basis of future wheat pan-genome studies.

  10. Comparative population genomics of Fusarium graminearum reveals adaptive divergence among cereal head blight pathogens

    Science.gov (United States)

    In this study we sequenced the genomes of 60 Fusarium graminearum, the major fungal pathogen responsible for Fusarium head blight (FHB) in cereal crops world-wide. To investigate adaptive evolution of FHB pathogens, we performed population-level analyses to characterize genomic structure, signatures...

  11. Whole genome transcript profiling of drug induced steatosis in rats reveals a gene signature predictive of outcome.

    Directory of Open Access Journals (Sweden)

    Nishika Sahini

    Full Text Available Drug induced steatosis (DIS is characterised by excess triglyceride accumulation in the form of lipid droplets (LD in liver cells. To explore mechanisms underlying DIS we interrogated the publically available microarray data from the Japanese Toxicogenomics Project (TGP to study comprehensively whole genome gene expression changes in the liver of treated rats. For this purpose a total of 17 and 12 drugs which are diverse in molecular structure and mode of action were considered based on their ability to cause either steatosis or phospholipidosis, respectively, while 7 drugs served as negative controls. In our efforts we focused on 200 genes which are considered to be mechanistically relevant in the process of lipid droplet biogenesis in hepatocytes as recently published (Sahini and Borlak, 2014. Based on mechanistic considerations we identified 19 genes which displayed dose dependent responses while 10 genes showed time dependency. Importantly, the present study defined 9 genes (ANGPTL4, FABP7, FADS1, FGF21, GOT1, LDLR, GK, STAT3, and PKLR as signature genes to predict DIS. Moreover, cross tabulation revealed 9 genes to be regulated ≥10 times amongst the various conditions and included genes linked to glucose metabolism, lipid transport and lipogenesis as well as signalling events. Additionally, a comparison between drugs causing phospholipidosis and/or steatosis revealed 26 genes to be regulated in common including 4 signature genes to predict DIS (PKLR, GK, FABP7 and FADS1. Furthermore, a comparison between in vivo single dose (3, 6, 9 and 24 h and findings from rat hepatocyte studies (2 h, 8 h, 24 h identified 10 genes which are regulated in common and contained 2 DIS signature genes (FABP7, FGF21. Altogether, our studies provide comprehensive information on mechanistically linked gene expression changes of a range of drugs causing steatosis and phospholipidosis and encourage the screening of DIS signature genes at the preclinical stage.

  12. Mycobacterial species as case-study of comparative genome analysis

    DEFF Research Database (Denmark)

    Zakham, F.; Belayachi, L.; Ussery, David

    2011-01-01

    . Pasteur 1173P2, M. leprae Br4923, M. marinum M, M. sp. KMS, M. sp. MCS, M. tuberculosis CDC1551, M. tuberculosis F11, M. tuberculosis H37Ra, M. tuberculosis H37Rv, M. tuberculosis KZN 1435 , M. ulcerans Agy99,and M. vanbaalenii PYR—1, For this purpose a comparison has been done based on their length...... defined for twelve Mycobacterial species. We have also introduced the genome atlas of the reference strain M. tuberculosis H37Rv which can give a good overview of this genome. And for examining the phylogenetic relationships among these bacteria, a phylogenic tree has been constructed from 16S rRNA gene...... the evolutionary events of these species and improving drugs, vaccines, and diagnostics tools for controlling Mycobacterial diseases. In this present study we aim to outline a comparative genome analysis of fourteen Mycobacterial genomes: M. avium subsp. paratuberculosis K—10, M. bovis AF2122/97, M. bovis BCG str...

  13. The mitochondrial genome of Grateloupia taiwanensis (Halymeniaceae, Rhodophyta) and comparative mitochondrial genomics of red algae.

    Science.gov (United States)

    DePriest, Michael S; Bhattacharya, Debashish; López-Bautista, Juan M

    2014-10-01

    Although red algae are economically highly valuable for their gelatinous cell wall compounds as well as being integral parts of marine benthic habitats, very little genome data are currently available. We present mitochondrial genome sequence data from the red alga Grateloupia taiwanensis S.-M. Lin & H.-Y. Liang. Comprising 28,906 nucleotide positions, the mitochondrial genome contig contains 25 protein-coding genes and 24 transfer RNA genes. It is highly similar to other red algal genomes in gene content as well as overall structure. An intron in the cox1 gene was found to be shared by G. taiwanensis and Grateloupia angusta (Okamura) S. Kawaguchi & H. W. Wang. We also used whole-genome alignments to compare G. taiwanensis to different groups of red algae, and these results are consistent with the currently accepted phylogeny of Rhodophyta. © 2014 Marine Biological Laboratory.

  14. Discovery and Characterization of Novel Signatures from the Ricinus communis L. (Castor Bean) Genome

    Science.gov (United States)

    2006-11-01

    2006 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Discovery And Characterization Of Novel Signatures From The Ricinus Communis...pressed herbarium specimens prepared from sequenced plants.) Lane 2, PI167112; lane 3, 167287; lane 4, 167342; lane 5, 170684; lane 6, 170686; lane

  15. Comparative genomics of four closely related Clostridium perfringens bacteriophages reveals variable evolution among core genes with therapeutic potential

    Directory of Open Access Journals (Sweden)

    Siragusa Gregory R

    2011-06-01

    Full Text Available Abstract Background Because biotechnological uses of bacteriophage gene products as alternatives to conventional antibiotics will require a thorough understanding of their genomic context, we sequenced and analyzed the genomes of four closely related phages isolated from Clostridium perfringens, an important agricultural and human pathogen. Results Phage whole-genome tetra-nucleotide signatures and proteomic tree topologies correlated closely with host phylogeny. Comparisons of our phage genomes to 26 others revealed three shared COGs; of particular interest within this core genome was an endolysin (PF01520, an N-acetylmuramoyl-L-alanine amidase and a holin (PF04531. Comparative analyses of the evolutionary history and genomic context of these common phage proteins revealed two important results: 1 strongly significant host-specific sequence variation within the endolysin, and 2 a protein domain architecture apparently unique to our phage genomes in which the endolysin is located upstream of its associated holin. Endolysin sequences from our phages were one of two very distinct genotypes distinguished by variability within the putative enzymatically-active domain. The shared or core genome was comprised of genes with multiple sequence types belonging to five pfam families, and genes belonging to 12 pfam families, including the holin genes, which were nearly identical. Conclusions Significant genomic diversity exists even among closely-related bacteriophages. Holins and endolysins represent conserved functions across divergent phage genomes and, as we demonstrate here, endolysins can have significant variability and host-specificity even among closely-related genomes. Endolysins in our phage genomes may be subject to different selective pressures than the rest of the genome. These findings may have important implications for potential biotechnological applications of phage gene products.

  16. Whole Genome Characterization, Phylogenetic and Genome Signature Analysis of Human Pandemic H1N1 Virus in Thailand, 2009–2012

    Science.gov (United States)

    Makkoch, Jarika; Suwannakarn, Kamol; Payungporn, Sunchai; Prachayangprecha, Slinporn; Cheiocharnsin, Thaweesak; Linsuwanon, Piyada; Theamboonlers, Apiradee; Poovorawan, Yong

    2012-01-01

    Background Three waves of human pandemic influenza occurred in Thailand in 2009–2012. The genome signature features and evolution of pH1N1 need to be characterized to elucidate the aspects responsible for the multiple waves of pandemic. Methodology/Findings Forty whole genome sequences and 584 partial sequences of pH1N1 circulating in Thailand, divided into 1st, 2nd and 3rd wave and post-pandemic were characterized and 77 genome signatures were analyzed. Phylogenetic trees of concatenated whole genome and HA gene sequences were constructed calculating substitution rate and dN/dS of each gene. Phylogenetic analysis showed a distinct pattern of pH1N1 circulation in Thailand, with the first two isolates from May, 2009 belonging to clade 5 while clades 5, 6 and 7 co-circulated during the first wave of pH1N1 pandemic in Thailand. Clade 8 predominated during the second wave and different proportions of the pH1N1 viruses circulating during the third wave and post pandemic period belonged to clades 8, 11.1 and 11.2. The mutation analysis of pH1N1 revealed many adaptive mutations which have become the signature of each clade and may be responsible for the multiple pandemic waves in Thailand, especially with regard to clades 11.1 and 11.2 as evidenced with V731I, G154D of PB1 gene, PA I330V, HA A214T S160G and S202T. The substitution rate of pH1N1 in Thailand ranged from 2.53×10−3±0.02 (M2 genes) to 5.27×10−3±0.03 per site per year (NA gene). Conclusions All results suggested that this virus is still adaptive, maybe to evade the host's immune response and tends to remain in the human host although the dN/dS were under purifying selection in all 8 genes. Due to the gradual evolution of pH1N1 in Thailand, continuous monitoring is essential for evaluation and surveillance to be prepared for and able to control future influenza activities. PMID:23251479

  17. Genome-wide search for Zelda-like chromatin signatures identifies GAF as a pioneer factor in early fly development.

    Science.gov (United States)

    Moshe, Arbel; Kaplan, Tommy

    2017-07-04

    The protein Zelda was shown to play a key role in early Drosophila development, binding thousands of promoters and enhancers prior to maternal-to-zygotic transition (MZT), and marking them for transcriptional activation. Recently, we showed that Zelda acts through specific chromatin patterns of histone modifications to mark developmental enhancers and active promoters. Intriguingly, some Zelda sites still maintain these chromatin patterns in Drosophila embryos lacking maternal Zelda protein. This suggests that additional Zelda-like pioneer factors may act in early fly embryos. We developed a computational method to analyze and refine the chromatin landscape surrounding early Zelda peaks, using a multichannel spectral clustering. This allowed us to characterize their chromatin patterns through MZT (mitotic cycles 8-14). Specifically, we focused on H3K4me1, H3K4me3, H3K18ac, H3K27ac, and H3K27me3 and identified three different classes of chromatin signatures, matching "promoters," "enhancers" and "transiently bound" Zelda peaks. We then further scanned the genome using these chromatin patterns and identified additional loci-with no Zelda binding-that show similar chromatin patterns, resulting with hundreds of Zelda-independent putative enhancers. These regions were found to be enriched with GAGA factor (GAF, Trl) and are typically located near early developmental zygotic genes. Overall our analysis suggests that GAF, together with Zelda, plays an important role in activating the zygotic genome. As we show, our computational approach offers an efficient algorithm for characterizing chromatin signatures around some loci of interest and allows a genome-wide identification of additional loci with similar chromatin patterns.

  18. Genome-wide DNA methylation profiling in the superior temporal gyrus reveals epigenetic signatures associated with Alzheimer's disease.

    Science.gov (United States)

    Watson, Corey T; Roussos, Panos; Garg, Paras; Ho, Daniel J; Azam, Nidha; Katsel, Pavel L; Haroutunian, Vahram; Sharp, Andrew J

    2016-01-19

    Alzheimer's disease affects ~13% of people in the United States 65 years and older, making it the most common neurodegenerative disorder. Recent work has identified roles for environmental, genetic, and epigenetic factors in Alzheimer's disease risk. We performed a genome-wide screen of DNA methylation using the Illumina Infinium HumanMethylation450 platform on bulk tissue samples from the superior temporal gyrus of patients with Alzheimer's disease and non-demented controls. We paired a sliding window approach with multivariate linear regression to characterize Alzheimer's disease-associated differentially methylated regions (DMRs). We identified 479 DMRs exhibiting a strong bias for hypermethylated changes, a subset of which were independently associated with aging. DMR intervals overlapped 475 RefSeq genes enriched for gene ontology categories with relevant roles in neuron function and development, as well as cellular metabolism, and included genes reported in Alzheimer's disease genome-wide and epigenome-wide association studies. DMRs were enriched for brain-specific histone signatures and for binding motifs of transcription factors with roles in the brain and Alzheimer's disease pathology. Notably, hypermethylated DMRs preferentially overlapped poised promoter regions, marked by H3K27me3 and H3K4me3, previously shown to co-localize with aging-associated hypermethylation. Finally, the integration of DMR-associated single nucleotide polymorphisms with Alzheimer's disease genome-wide association study risk loci and brain expression quantitative trait loci highlights multiple potential DMRs of interest for further functional analysis. We have characterized changes in DNA methylation in the superior temporal gyrus of patients with Alzheimer's disease, highlighting novel loci that facilitate better characterization of pathways and mechanisms underlying Alzheimer's disease pathogenesis, and improve our understanding of epigenetic signatures that may contribute to the

  19. Draft genome sequence of Cellulomonas carbonis T26T and comparative analysis of six Cellulomonas genomes

    OpenAIRE

    Zhuang, Weiping; Zhang, Shengzhe; Xia, Xian; Wang, Gejiao

    2015-01-01

    Most Cellulomonas strains are cellulolytic and this feature may be applied in straw degradation and bioremediation. In this study, Cellulomonas carbonis T26T, Cellulomonas bogoriensis DSM 16987T and Cellulomonas cellasea 20108T were sequenced. Here we described the draft genomic information of C. carbonis T26T and compared it to the related Cellulomonas genomes. Strain T26T has a 3,990,666?bp genome size with a G?+?C content of 73.4?%, containing 3418 protein-coding genes and 59 RNA genes. Th...

  20. Comparative genomics of wild type yeast strains unveils important genome diversity

    Directory of Open Access Journals (Sweden)

    Pereira Patrícia M

    2008-11-01

    Full Text Available Abstract Background Genome variability generates phenotypic heterogeneity and is of relevance for adaptation to environmental change, but the extent of such variability in natural populations is still poorly understood. For example, selected Saccharomyces cerevisiae strains are variable at the ploidy level, have gene amplifications, changes in chromosome copy number, and gross chromosomal rearrangements. This suggests that genome plasticity provides important genetic diversity upon which natural selection mechanisms can operate. Results In this study, we have used wild-type S. cerevisiae (yeast strains to investigate genome variation in natural and artificial environments. We have used comparative genome hybridization on array (aCGH to characterize the genome variability of 16 yeast strains, of laboratory and commercial origin, isolated from vineyards and wine cellars, and from opportunistic human infections. Interestingly, sub-telomeric instability was associated with the clinical phenotype, while Ty element insertion regions determined genomic differences of natural wine fermentation strains. Copy number depletion of ASP3 and YRF1 genes was found in all wild-type strains. Other gene families involved in transmembrane transport, sugar and alcohol metabolism or drug resistance had copy number changes, which also distinguished wine from clinical isolates. Conclusion We have isolated and genotyped more than 1000 yeast strains from natural environments and carried out an aCGH analysis of 16 strains representative of distinct genotype clusters. Important genomic variability was identified between these strains, in particular in sub-telomeric regions and in Ty-element insertion sites, suggesting that this type of genome variability is the main source of genetic diversity in natural populations of yeast. The data highlights the usefulness of yeast as a model system to unravel intraspecific natural genome diversity and to elucidate how natural

  1. Comparative genomics of wild type yeast strains unveils important genome diversity.

    Science.gov (United States)

    Carreto, Laura; Eiriz, Maria F; Gomes, Ana C; Pereira, Patrícia M; Schuller, Dorit; Santos, Manuel A S

    2008-11-04

    Genome variability generates phenotypic heterogeneity and is of relevance for adaptation to environmental change, but the extent of such variability in natural populations is still poorly understood. For example, selected Saccharomyces cerevisiae strains are variable at the ploidy level, have gene amplifications, changes in chromosome copy number, and gross chromosomal rearrangements. This suggests that genome plasticity provides important genetic diversity upon which natural selection mechanisms can operate. In this study, we have used wild-type S. cerevisiae (yeast) strains to investigate genome variation in natural and artificial environments. We have used comparative genome hybridization on array (aCGH) to characterize the genome variability of 16 yeast strains, of laboratory and commercial origin, isolated from vineyards and wine cellars, and from opportunistic human infections. Interestingly, sub-telomeric instability was associated with the clinical phenotype, while Ty element insertion regions determined genomic differences of natural wine fermentation strains. Copy number depletion of ASP3 and YRF1 genes was found in all wild-type strains. Other gene families involved in transmembrane transport, sugar and alcohol metabolism or drug resistance had copy number changes, which also distinguished wine from clinical isolates. We have isolated and genotyped more than 1000 yeast strains from natural environments and carried out an aCGH analysis of 16 strains representative of distinct genotype clusters. Important genomic variability was identified between these strains, in particular in sub-telomeric regions and in Ty-element insertion sites, suggesting that this type of genome variability is the main source of genetic diversity in natural populations of yeast. The data highlights the usefulness of yeast as a model system to unravel intraspecific natural genome diversity and to elucidate how natural selection shapes the yeast genome.

  2. Comparative genomics and evolution of conserved noncoding elements (CNE in rainbow trout

    Directory of Open Access Journals (Sweden)

    Ferguson Moira M

    2009-06-01

    Full Text Available Abstract Background Recent advances in the accumulation of genetic mapping and DNA sequence information from several salmonid species support the long standing view of an autopolyploid origin of these fishes (i.e., 4R. However, the paralogy relationships of the chromosomal segments descendent from earlier polyploidization events (i.e., 2R/3R largely remain unknown, mainly due to an unbalanced pseudogenization of paralogous genes that were once resident on the ancient duplicated segments. Inter-specific conserved noncoding elements (CNE might hold the key in identifying these regions, if they are associated with arrays of genes that have been highly conserved in syntenic blocks through evolution. To test this hypothesis, we investigated the chromosomal positions of subset of CNE in the rainbow trout genome using a comparative genomic framework. Results Through a genome wide analysis, we selected 41 pairs of adjacent CNE located on various chromosomes in zebrafish and obtained their intervening, less conserved, sequence information from rainbow trout. We identified 56 distinct fragments corresponding to about 150 Kbp of sequence data that were localized to 67 different chromosomal regions in the rainbow trout genome. The genomic positions of many duplicated CNE provided additional support for some previously suggested homeologies in this species. Additionally, we now propose 40 new potential paralogous affinities by analyzing the variation in the segregation patterns of some multi-copy CNE along with the synteny association comparison using several model vertebrates. Some of these regions appear to carry signatures of the 1R, 2R or 3R duplications. A subset of these CNE markers also demonstrated high utility in identifying homologous chromosomal segments in the genomes of Atlantic salmon and Arctic charr. Conclusion CNE seem to be more efficacious than coding sequences in providing insights into the ancient paralogous affinities within the

  3. Genomic signatures of geographic isolation and natural selection in coral reef fishes.

    Science.gov (United States)

    Gaither, Michelle R; Bernal, Moisés A; Coleman, Richard R; Bowen, Brian W; Jones, Shelley A; Simison, W Brian; Rocha, Luiz A

    2015-04-01

    The drivers of speciation remain among the most controversial topics in evolutionary biology. Initially, Darwin emphasized natural selection as a primary mechanism of speciation, but the architects of the modern synthesis largely abandoned that view in favour of divergence by geographic isolation. The balance between selection and isolation is still at the forefront of the evolutionary debate, especially for the world's tropical oceans where biodiversity is high, but isolating barriers are few. Here, we identify the drivers of speciation in Pacific reef fishes of the genus Acanthurus by comparative genome scans of two peripheral populations that split from a large Central-West Pacific lineage at roughly the same time. Mitochondrial sequences indicate that populations in the Hawaiian Archipelago and the Marquesas Islands became isolated approximately 0.5 Ma. The Hawaiian lineage is morphologically indistinguishable from the widespread Pacific form, but the Marquesan form is recognized as a distinct species that occupies an unusual tropical ecosystem characterized by upwelling, turbidity, temperature fluctuations, algal blooms and little coral cover. An analysis of 3737 SNPs reveals a strong signal of selection at the Marquesas, with 59 loci under disruptive selection including an opsin Rh2 locus. While both the Hawaiian and Marquesan populations indicate signals of drift, the former shows a weak signal of selection that is comparable with populations in the Central-West Pacific. This contrast between closely related lineages reveals one population diverging due primarily to geographic isolation and genetic drift, and the other achieving taxonomic species status under the influence of selection. © 2015 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  4. Landscape genomic approach to detect selection signatures in locally adapted Brazilian swine genetic groups

    OpenAIRE

    Cesconeto, Robson Jose; Joost, Stéphane; McManus, Concepta Margaret; Paiva, Samuel Rezende; Cobuci, Jaime Araujo; Braccini, Jose

    2017-01-01

    Abstract Samples of 191 animals from 18 different Brazilian locally adapted swine genetic groups were genotyped using Illumina Porcine SNP60 BeadChip in order to identify selection signatures related to the monthly variation of Brazilian environmental variables. Using BayeScan software, 71 SNP markers were identified as FST outliers and 60 genotypes (58 markers) were found by Samβada software in 371 logistic models correlated with 112 environmental variables. Five markers were identified in b...

  5. Moth sex chromatin probed by comparative genomic hybridization (CGH)

    Czech Academy of Sciences Publication Activity Database

    Sahara, K.; Marec, František; Eickhoff, U.; Traut, W.

    2003-01-01

    Roč. 46, - (2003), s. 339-342 ISSN 0831-2796 R&D Projects: GA AV ČR IAA6007307 Institutional research plan: CEZ:AV0Z5007907 Keywords : Lepidoptera * comparative genomic hybridization Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.861, year: 2003

  6. Comparing genetic variants detected in the 1000 genomes project ...

    Indian Academy of Sciences (India)

    Comparing genetic variants detected in the 1000 genomes project with SNPs determined by the International HapMap Consortium ... for Toxicological Research, US Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079, USA; Thomson Reuters, IP and Science, 22 Thomson Place, Boston, MA 02210, USA ...

  7. Breakpoint identification and smoothing of array comparative genomic hybridization data

    NARCIS (Netherlands)

    Jong, C.; Marchiori, E.; Meijer, G.J.; van der Vaart, A.W.; Ylstra, B.

    2004-01-01

    Summary: We describe a tool, called aCGH-Smooth, for the automated identification of breakpoints and smoothing of microarray comparative genomic hybridization (array CGH) data. aCGH-Smooth is written in visual C++, has a user-friendly interface including a visualization of the results and

  8. Comparing genetic variants detected in the 1000 genomes project ...

    Indian Academy of Sciences (India)

    Single-nucleotide polymorphisms (SNPs) determined based on SNP arrays from the international HapMap consortium (HapMap) and the genetic variants detected in the 1000 genomes project (1KGP) can serve as two references for genomewide association studies (GWAS). We conducted comparative analyses to provide ...

  9. Comparative Genomics-A Powerful New Tool in Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 8. Comparative Genomics - A Powerful New Tool in Biology. Anand K Bachhawat. General Article Volume 11 Issue 8 August 2006 pp 22-40. Fulltext. Click here to view fulltext PDF. Permanent link:

  10. Lactobacillus paracasei comparative genomics: towards species pan-genome definition and exploitation of diversity.

    Directory of Open Access Journals (Sweden)

    Tamara Smokvina

    Full Text Available Lactobacillus paracasei is a member of the normal human and animal gut microbiota and is used extensively in the food industry in starter cultures for dairy products or as probiotics. With the development of low-cost, high-throughput sequencing techniques it has become feasible to sequence many different strains of one species and to determine its "pan-genome". We have sequenced the genomes of 34 different L. paracasei strains, and performed a comparative genomics analysis. We analysed genome synteny and content, focussing on the pan-genome, core genome and variable genome. Each genome was shown to contain around 2800-3100 protein-coding genes, and comparative analysis identified over 4200 ortholog groups that comprise the pan-genome of this species, of which about 1800 ortholog groups make up the conserved core. Several factors previously associated with host-microbe interactions such as pili, cell-envelope proteinase, hydrolases p40 and p75 or the capacity to produce short branched-chain fatty acids (bkd operon are part of the L. paracasei core genome present in all analysed strains. The variome consists mainly of hypothetical proteins, phages, plasmids, transposon/conjugative elements, and known functions such as sugar metabolism, cell-surface proteins, transporters, CRISPR-associated proteins, and EPS biosynthesis proteins. An enormous variety and variability of sugar utilization gene cassettes were identified, with each strain harbouring between 25-53 cassettes, reflecting the high adaptability of L. paracasei to different niches. A phylogenomic tree was constructed based on total genome contents, and together with an analysis of horizontal gene transfer events we conclude that evolution of these L. paracasei strains is complex and not always related to niche adaptation. The results of this genome content comparison was used, together with high-throughput growth experiments on various carbohydrates, to perform gene-trait matching analysis

  11. Sequencing and comparative genome analysis of two pathogenic Streptococcus gallolyticus subspecies: genome plasticity, adaptation and virulence.

    Directory of Open Access Journals (Sweden)

    I-Hsuan Lin

    Full Text Available Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I and S. pasteurianus ATCC 43144 (biotype II.2. The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92% and 1607 (86% of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops.

  12. MicroScope: a platform for microbial genome annotation and comparative genomics.

    Science.gov (United States)

    Vallenet, D; Engelen, S; Mornico, D; Cruveiller, S; Fleury, L; Lajus, A; Rouy, Z; Roche, D; Salvignol, G; Scarpelli, C; Médigue, C

    2009-01-01

    The initial outcome of genome sequencing is the creation of long text strings written in a four letter alphabet. The role of in silico sequence analysis is to assist biologists in the act of associating biological knowledge with these sequences, allowing investigators to make inferences and predictions that can be tested experimentally. A wide variety of software is available to the scientific community, and can be used to identify genomic objects, before predicting their biological functions. However, only a limited number of biologically interesting features can be revealed from an isolated sequence. Comparative genomics tools, on the other hand, by bringing together the information contained in numerous genomes simultaneously, allow annotators to make inferences based on the idea that evolution and natural selection are central to the definition of all biological processes. We have developed the MicroScope platform in order to offer a web-based framework for the systematic and efficient revision of microbial genome annotation and comparative analysis (http://www.genoscope.cns.fr/agc/microscope). Starting with the description of the flow chart of the annotation processes implemented in the MicroScope pipeline, and the development of traditional and novel microbial annotation and comparative analysis tools, this article emphasizes the essential role of expert annotation as a complement of automatic annotation. Several examples illustrate the use of implemented tools for the review and curation of annotations of both new and publicly available microbial genomes within MicroScope's rich integrated genome framework. The platform is used as a viewer in order to browse updated annotation information of available microbial genomes (more than 440 organisms to date), and in the context of new annotation projects (117 bacterial genomes). The human expertise gathered in the MicroScope database (about 280,000 independent annotations) contributes to improve the quality of

  13. Evolutionary biology through the lens of budding yeast comparative genomics.

    Science.gov (United States)

    Marsit, Souhir; Leducq, Jean-Baptiste; Durand, Éléonore; Marchant, Axelle; Filteau, Marie; Landry, Christian R

    2017-10-01

    The budding yeast Saccharomyces cerevisiae is a highly advanced model system for studying genetics, cell biology and systems biology. Over the past decade, the application of high-throughput sequencing technologies to this species has contributed to this yeast also becoming an important model for evolutionary genomics. Indeed, comparative genomic analyses of laboratory, wild and domesticated yeast populations are providing unprecedented detail about many of the processes that govern evolution, including long-term processes, such as reproductive isolation and speciation, and short-term processes, such as adaptation to natural and domestication-related environments.

  14. African relapsing fever borreliae genomospecies revealed by comparative genomics

    Directory of Open Access Journals (Sweden)

    Haitham eElbir

    2014-05-01

    Full Text Available Background:Relapsing fever borreliae are vector-borne bacteria responsible for febrile infection in humans in North America, Africa, Asia and in the Iberian Peninsula in Europe. Relapsing fever borreliae are phylogenetically closely related, yet they differ in pathogenicity and vectors. Their long-term taxonomy, based on geography and vector grouping, needs a re-appraisal in the genomic area. We therefore embarked into genomic analyses of relapsing fever borreliae, focusing on species found in Africa. Results:Genome-wide phylogenetic analyses group Old World Borrelia crocidurae, Borrelia hispanica, B. duttonii and B. recurrentis in one clade, and New World Borrelia turicatae and Borrelia hermsii in a second clade. Accordingly, average nucleotide identity is 99% among B. duttonii, B. recurrentis and B. crocidurae and 96% between latter borreliae and B. hispanica while the similarity is 86% between Old World and New World borreliae. Comparative genomics indicates that the Old World relapsing fever B. duttonii, B. recurrentis, B. crocidurae and B. hispanica have a 2,514-gene pan-genome and a 933-gene core genome that includes 788 chromosomal and 145 plasmidic genes. Analysing the role that natural selection has played in the evolution of Old World borreliae species revealed that 55 loci were under positive diversifying selection, including loci coding for membrane, flagellar and chemotaxis proteins, three categories associated with adaption to specific niches. Conclusions:Genomic analyses led to a reappraisal of the taxonomy of relapsing fever borreliae in Africa. These analyses suggest that B. crocidurae, B. duttonii and B. recurrentis are ecotypes of a unique genomospecies, while B. hispanica is a distinct species.

  15. Altered metabolomic-genomic signature: A potential noninvasive biomarker of epilepsy.

    Science.gov (United States)

    Wu, Helen C; Dachet, Fabien; Ghoddoussi, Farhad; Bagla, Shruti; Fuerst, Darren; Stanley, Jeffrey A; Galloway, Matthew P; Loeb, Jeffrey A

    2017-09-01

    This study aimed to identify noninvasive biomarkers of human epilepsy that can reliably detect and localize epileptic brain regions. Having noninvasive biomarkers would greatly enhance patient diagnosis, patient monitoring, and novel therapy development. At the present time, only surgically invasive, direct brain recordings are capable of detecting these regions with precision, which severely limits the pace and scope of both clinical management and research progress in epilepsy. We compared high versus low or nonspiking regions in nine medically intractable epilepsy surgery patients by performing integrated metabolomic-genomic-histological analyses of electrically mapped human cortical regions using high-resolution magic angle spinning proton magnetic resonance spectroscopy, cDNA microarrays, and histological analysis. We found a highly consistent and predictive metabolite logistic regression model with reduced lactate and increased creatine plus phosphocreatine and choline, suggestive of a chronically altered metabolic state in epileptic brain regions. Linking gene expression, cellular, and histological differences to these key metabolites using a hierarchical clustering approach predicted altered metabolic vascular coupling in the affected regions. Consistently, these predictions were validated histologically, showing both neovascularization and newly discovered, millimeter-sized microlesions. Using a systems biology approach on electrically mapped human cortex provides new evidence for spatially segregated, metabolic derangements in both neurovascular and synaptic architecture in human epileptic brain regions that could be a noninvasively detectable biomarker of epilepsy. These findings both highlight the immense power of a systems biology approach and identify a potentially important role that magnetic resonance spectroscopy can play in the research and clinical management of epilepsy. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  16. Genomic and Genotypic Characterization of Cylindrospermopsis raciborskii: Toward an Intraspecific Phylogenetic Evaluation by Comparative Genomics

    Directory of Open Access Journals (Sweden)

    Vinicius A. C. Abreu

    2018-02-01

    Full Text Available Cylindrospermopsis raciborskii is a freshwater cyanobacterial species with increasing bloom reports worldwide that are likely due to factors related to climate change. In addition to the deleterious effects of blooms on aquatic ecosystems, the majority of ecotypes can synthesize toxic secondary metabolites causing public health issues. To overcome the harmful effects of C. raciborskii blooms, it is important to advance knowledge of diversity, genetic variation, and evolutionary processes within populations. An efficient approach to exploring this diversity and understanding the evolution of C. raciborskii is to use comparative genomics. Here, we report two new draft genomes of C. raciborskii (strains CENA302 and CENA303 from Brazilian isolates of different origins and explore their molecular diversity, phylogeny, and evolutionary diversification by comparing their genomes with sequences from other strains available in public databases. The results obtained by comparing seven C. raciborskii and the Raphidiopsis brookii D9 genomes revealed a set of conserved core genes and a variable set of accessory genes, such as those involved in the biosynthesis of natural products, heterocyte glycolipid formation, and nitrogen fixation. Gene cluster arrangements related to the biosynthesis of the antifungal cyclic glycosylated lipopeptide hassallidin were identified in four C. raciborskii genomes, including the non-nitrogen fixing strain CENA303. Shifts in gene clusters involved in toxin production according to geographic origins were observed, as well as a lack of nitrogen fixation (nif and heterocyte glycolipid (hgl gene clusters in some strains. Single gene phylogeny (16S rRNA sequences was congruent with phylogeny based on 31 concatenated housekeeping protein sequences, and both analyses have shown, with high support values, that the species C. raciborskii is monophyletic. This comparative genomics study allowed a species-wide view of the biological

  17. Comparative genome analysis and genome evolution of members of the magnaporthaceae family of fungi.

    Science.gov (United States)

    Okagaki, Laura H; Sailsbery, Joshua K; Eyre, Alexander W; Dean, Ralph A

    2016-02-25

    Magnaporthaceae, a family of ascomycetes, includes three fungi of great economic importance that cause disease in cereal and turf grasses: Magnaporthe oryzae (rice blast), Gaeumannomyces graminis var. tritici (take-all disease), and Magnaporthe poae (summer patch disease). Recently, the sequenced and assembled genomes for these three fungi were reported. Here, the genomes were compared for orthologous genes in order to identified genes that are unique to the Magnaporthaceae family of fungi. In addition, ortholog clustering was used to identify a core proteome for the Magnaporthaceae, which was examined for diversifying and purifying selection and evidence of two-speed genome evolution. A genome-scale comparative study was conducted across 74 fungal genomes to identify clusters of orthologous genes unique to the three Magnaporthaceae species as well as species specific genes. We found 1149 clusters that were unique to the Magnaporthaceae family of fungi with 295 of those containing genes from all three species. Gene clusters involved in metabolic and enzymatic activities were highly represented in the Magnaporthaceae specific clusters. Also highly represented in the Magnaporthaceae specific clusters as well as in the species specific genes were transcriptional regulators. In addition, we examined the relationship between gene evolution and distance to repetitive elements found in the genome. No correlations between diversifying or purifying selection and distance to repetitive elements or an increased rate of evolution in secreted and small secreted proteins were observed. Taken together, these data show that at the genome level, there is no evidence to suggest multi-speed genome evolution or that proximity to repetitive elements play a role in diversification of genes.

  18. Phylogeny and comparative genome analysis of a Basidiomycete fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert W.; Salamov, Asaf; Grigoriev, Igor; Hibbett, David

    2011-03-14

    Fungi of the phylum Basidiomycota, make up some 37percent of the described fungi, and are important from the perspectives of forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, plant pathogenic rusts and smuts, and some human pathogens. To better understand these important fungi, we have undertaken a comparative genomic analysis of the Basidiomycetes with available sequenced genomes. We report a phylogeny that sheds light on previously unclear evolutionary relationships among the Basidiomycetes. We also define a `core proteome? based on protein families conserved in all Basidiomycetes. We identify key expansions and contractions in protein families that may be responsible for the degradation of plant biomass such as cellulose, hemicellulose, and lignin. Finally, we speculate as to the genomic changes that drove such expansions and contractions.

  19. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

    Science.gov (United States)

    Ma, Li-Jun; van der Does, H. Charlotte; Borkovich, Katherine A.; Coleman, Jeffrey J.; Daboussi, Marie-Josée; Di Pietro, Antonio; Dufresne, Marie; Freitag, Michael; Grabherr, Manfred; Henrissat, Bernard; Houterman, Petra M.; Kang, Seogchan; Shim, Won-Bo; Woloshuk, Charles; Xie, Xiaohui; Xu, Jin-Rong; Antoniw, John; Baker, Scott E.; Bluhm, Burton H.; Breakspear, Andrew; Brown, Daren W.; Butchko, Robert A. E.; Chapman, Sinead; Coulson, Richard; Coutinho, Pedro M.; Danchin, Etienne G. J.; Diener, Andrew; Gale, Liane R.; Gardiner, Donald M.; Goff, Stephen; Hammond-Kosack, Kim E.; Hilburn, Karen; Hua-Van, Aurélie; Jonkers, Wilfried; Kazan, Kemal; Kodira, Chinnappa D.; Koehrsen, Michael; Kumar, Lokesh; Lee, Yong-Hwan; Li, Liande; Manners, John M.; Miranda-Saavedra, Diego; Mukherjee, Mala; Park, Gyungsoon; Park, Jongsun; Park, Sook-Young; Proctor, Robert H.; Regev, Aviv; Ruiz-Roldan, M. Carmen; Sain, Divya; Sakthikumar, Sharadha; Sykes, Sean; Schwartz, David C.; Turgeon, B. Gillian; Wapinski, Ilan; Yoder, Olen; Young, Sarah; Zeng, Qiandong; Zhou, Shiguo; Galagan, James; Cuomo, Christina A.; Kistler, H. Corby; Rep, Martijn

    2011-01-01

    Fusarium species are among the most important phytopathogenic and toxigenic fungi. To understand the molecular underpinnings of pathogenicity in the genus Fusarium, we compared the genomes of three phenotypically diverse species: Fusarium graminearum, Fusarium verticillioides and Fusarium oxysporum f. sp. lycopersici. Our analysis revealed lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes and account for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity, indicative of horizontal acquisition. Experimentally, we demonstrate the transfer of two LS chromosomes between strains of F. oxysporum, converting a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in F. oxysporum. These findings put the evolution of fungal pathogenicity into a new perspective. PMID:20237561

  20. Comparative Analysis of Predicted Gene Expression among Crenarchaeal Genomes

    Directory of Open Access Journals (Sweden)

    Shibsankar Das

    2017-03-01

    Full Text Available Research into new methods for identifying highly expressed genes in anonymous genome sequences has been going on for more than 15 years. We presented here an alternative approach based on modified score of relative codon usage bias to identify highly expressed genes in crenarchaeal genomes. The proposed algorithm relies exclusively on sequence features for identifying the highly expressed genes. In this study, a comparative analysis of predicted highly expressed genes in five crenarchaeal genomes was performed using the score of Modified Relative Codon Bias Strength (MRCBS as a numerical estimator of gene expression level. We found a systematic strong correlation between Codon Adaptation Index and MRCBS. Additionally, MRCBS correlated well with other expression measures. Our study indicates that MRCBS can consistently capture the highly expressed genes.

  1. The Chlamydia psittaci genome: a comparative analysis of intracellular pathogens.

    Science.gov (United States)

    Voigt, Anja; Schöfl, Gerhard; Saluz, Hans Peter

    2012-01-01

    Chlamydiaceae are a family of obligate intracellular pathogens causing a wide range of diseases in animals and humans, and facing unique evolutionary constraints not encountered by free-living prokaryotes. To investigate genomic aspects of infection, virulence and host preference we have sequenced Chlamydia psittaci, the pathogenic agent of ornithosis. A comparison of the genome of the avian Chlamydia psittaci isolate 6BC with the genomes of other chlamydial species, C. trachomatis, C. muridarum, C. pneumoniae, C. abortus, C. felis and C. caviae, revealed a high level of sequence conservation and synteny across taxa, with the major exception of the human pathogen C. trachomatis. Important differences manifest in the polymorphic membrane protein family specific for the Chlamydiae and in the highly variable chlamydial plasticity zone. We identified a number of psittaci-specific polymorphic membrane proteins of the G family that may be related to differences in host-range and/or virulence as compared to closely related Chlamydiaceae. We calculated non-synonymous to synonymous substitution rate ratios for pairs of orthologous genes to identify putative targets of adaptive evolution and predicted type III secreted effector proteins. This study is the first detailed analysis of the Chlamydia psittaci genome sequence. It provides insights in the genome architecture of C. psittaci and proposes a number of novel candidate genes mostly of yet unknown function that may be important for pathogen-host interactions.

  2. Comparative analysis of methods for genome-wide nucleosome cartography.

    Science.gov (United States)

    Quintales, Luis; Vázquez, Enrique; Antequera, Francisco

    2015-07-01

    Nucleosomes contribute to compacting the genome into the nucleus and regulate the physical access of regulatory proteins to DNA either directly or through the epigenetic modifications of the histone tails. Precise mapping of nucleosome positioning across the genome is, therefore, essential to understanding the genome regulation. In recent years, several experimental protocols have been developed for this purpose that include the enzymatic digestion, chemical cleavage or immunoprecipitation of chromatin followed by next-generation sequencing of the resulting DNA fragments. Here, we compare the performance and resolution of these methods from the initial biochemical steps through the alignment of the millions of short-sequence reads to a reference genome to the final computational analysis to generate genome-wide maps of nucleosome occupancy. Because of the lack of a unified protocol to process data sets obtained through the different approaches, we have developed a new computational tool (NUCwave), which facilitates their analysis, comparison and assessment and will enable researchers to choose the most suitable method for any particular purpose. NUCwave is freely available at http://nucleosome.usal.es/nucwave along with a step-by-step protocol for its use. © The Author 2014. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  3. The Chlamydia psittaci genome: a comparative analysis of intracellular pathogens.

    Directory of Open Access Journals (Sweden)

    Anja Voigt

    Full Text Available Chlamydiaceae are a family of obligate intracellular pathogens causing a wide range of diseases in animals and humans, and facing unique evolutionary constraints not encountered by free-living prokaryotes. To investigate genomic aspects of infection, virulence and host preference we have sequenced Chlamydia psittaci, the pathogenic agent of ornithosis.A comparison of the genome of the avian Chlamydia psittaci isolate 6BC with the genomes of other chlamydial species, C. trachomatis, C. muridarum, C. pneumoniae, C. abortus, C. felis and C. caviae, revealed a high level of sequence conservation and synteny across taxa, with the major exception of the human pathogen C. trachomatis. Important differences manifest in the polymorphic membrane protein family specific for the Chlamydiae and in the highly variable chlamydial plasticity zone. We identified a number of psittaci-specific polymorphic membrane proteins of the G family that may be related to differences in host-range and/or virulence as compared to closely related Chlamydiaceae. We calculated non-synonymous to synonymous substitution rate ratios for pairs of orthologous genes to identify putative targets of adaptive evolution and predicted type III secreted effector proteins.This study is the first detailed analysis of the Chlamydia psittaci genome sequence. It provides insights in the genome architecture of C. psittaci and proposes a number of novel candidate genes mostly of yet unknown function that may be important for pathogen-host interactions.

  4. A Web-Based Comparative Genomics Tutorial for Investigating Microbial Genomes

    Directory of Open Access Journals (Sweden)

    Michael Strong

    2009-12-01

    Full Text Available As the number of completely sequenced microbial genomes continues to rise at an impressive rate, it is important to prepare students with the skills necessary to investigate microorganisms at the genomic level. As a part of the core curriculum for first-year graduate students in the biological sciences, we have implemented a web-based tutorial to introduce students to the fields of comparative and functional genomics. The tutorial focuses on recent computational methods for identifying functionally linked genes and proteins on a genome-wide scale and was used to introduce students to the Rosetta Stone, Phylogenetic Profile, conserved Gene Neighbor, and Operon computational methods. Students learned to use a number of publicly available web servers and databases to identify functionally linked genes in the Escherichia coli genome, with emphasis on genome organization and operon structure. The overall effectiveness of the tutorial was assessed based on student evaluations and homework assignments. The tutorial is available to other educators at http://www.doe-mbi.ucla.edu/~strong/m253.php.

  5. The Whole Genome Assembly and Comparative Genomic Research of Thellungiella parvula (Extremophile Crucifer) Mitochondrion.

    Science.gov (United States)

    Wang, Xuelin; Bi, Changwei; Xu, Yiqing; Wei, Suyun; Dai, Xiaogang; Yin, Tongming; Ye, Ning

    2016-01-01

    The complete nucleotide sequences of the mitochondrial (mt) genome of an extremophile species Thellungiella parvula (T. parvula) have been determined with the lengths of 255,773 bp. T. parvula mt genome is a circular sequence and contains 32 protein-coding genes, 19 tRNA genes, and three ribosomal RNA genes with a 11.5% coding sequence. The base composition of 27.5% A, 27.5% T, 22.7% C, and 22.3% G in descending order shows a slight bias of 55% AT. Fifty-three repeats were identified in the mitochondrial genome of T. parvula, including 24 direct repeats, 28 tandem repeats (TRs), and one palindromic repeat. Furthermore, a total of 199 perfect microsatellites have been mined with a high A/T content (83.1%) through simple sequence repeat (SSR) analysis and they were distributed unevenly within this mitochondrial genome. We also analyzed other plant mitochondrial genomes' evolution in general, providing clues for the understanding of the evolution of organelles genomes in plants. Comparing with other Brassicaceae species, T. parvula is related to Arabidopsis thaliana whose characters of low temperature resistance have been well documented. This study will provide important genetic tools for other Brassicaceae species research and improve yields of economically important plants.

  6. Comparative genomics reveals diversity among xanthomonads infecting tomato and pepper

    LENUS (Irish Health Repository)

    Potnis, Neha

    2011-03-11

    Abstract Background Bacterial spot of tomato and pepper is caused by four Xanthomonas species and is a major plant disease in warm humid climates. The four species are distinct from each other based on physiological and molecular characteristics. The genome sequence of strain 85-10, a member of one of the species, Xanthomonas euvesicatoria (Xcv) has been previously reported. To determine the relationship of the four species at the genome level and to investigate the molecular basis of their virulence and differing host ranges, draft genomic sequences of members of the other three species were determined and compared to strain 85-10. Results We sequenced the genomes of X. vesicatoria (Xv) strain 1111 (ATCC 35937), X. perforans (Xp) strain 91-118 and X. gardneri (Xg) strain 101 (ATCC 19865). The genomes were compared with each other and with the previously sequenced Xcv strain 85-10. In addition, the molecular features were predicted that may be required for pathogenicity including the type III secretion apparatus, type III effectors, other secretion systems, quorum sensing systems, adhesins, extracellular polysaccharide, and lipopolysaccharide determinants. Several novel type III effectors from Xg strain 101 and Xv strain 1111 genomes were computationally identified and their translocation was validated using a reporter gene assay. A homolog to Ax21, the elicitor of XA21-mediated resistance in rice, and a functional Ax21 sulfation system were identified in Xcv. Genes encoding proteins with functions mediated by type II and type IV secretion systems have also been compared, including enzymes involved in cell wall deconstruction, as contributors to pathogenicity. Conclusions Comparative genomic analyses revealed considerable diversity among bacterial spot pathogens, providing new insights into differences and similarities that may explain the diverse nature of these strains. Genes specific to pepper pathogens, such as the O-antigen of the lipopolysaccharide cluster

  7. Haemophilus influenzae: using comparative genomics to accurately identify a highly recombinogenic human pathogen.

    Science.gov (United States)

    Price, Erin P; Sarovich, Derek S; Nosworthy, Elizabeth; Beissbarth, Jemima; Marsh, Robyn L; Pickering, Janessa; Kirkham, Lea-Ann S; Keil, Anthony D; Chang, Anne B; Smith-Vaughan, Heidi C

    2015-08-27

    Haemophilus influenzae is an opportunistic bacterial pathogen that exclusively colonises humans and is associated with both acute and chronic disease. Despite its clinical significance, accurate identification of H. influenzae is a non-trivial endeavour. H. haemolyticus can be misidentified as H. influenzae from clinical specimens using selective culturing methods, reflecting both the shared environmental niche and phenotypic similarities of these species. On the molecular level, frequent genetic exchange amongst Haemophilus spp. has confounded accurate identification of H. influenzae, leading to both false-positive and false-negative results with existing speciation assays. Whole-genome single-nucleotide polymorphism data from 246 closely related global Haemophilus isolates, including 107 Australian isolate genomes generated in this study, were used to construct a whole-genome phylogeny. Based on this phylogeny, H. influenzae could be differentiated from closely related species. Next, a H. influenzae-specific locus, fucP, was identified, and a novel TaqMan real-time PCR assay targeting fucP was designed. PCR specificity screening across a panel of clinically relevant species, coupled with in silico analysis of all species within the order Pasteurellales, demonstrated that the fucP assay was 100 % specific for H. influenzae; all other examined species failed to amplify. This study is the first of its kind to use large-scale comparative genomic analysis of Haemophilus spp. to accurately delineate H. influenzae and to identify a species-specific molecular signature for this species. The fucP assay outperforms existing H. influenzae targets, most of which were identified prior to the next-generation genomics era and thus lack validation across a large number of Haemophilus spp. We recommend use of the fucP assay in clinical and research laboratories for the most accurate detection and diagnosis of H. influenzae infection and colonisation.

  8. Evolutionary trajectories of snake genes and genomes revealed by comparative analyses of five-pacer viper

    Science.gov (United States)

    Yin, Wei; Wang, Zong-ji; Li, Qi-ye; Lian, Jin-ming; Zhou, Yang; Lu, Bing-zheng; Jin, Li-jun; Qiu, Peng-xin; Zhang, Pei; Zhu, Wen-bo; Wen, Bo; Huang, Yi-jun; Lin, Zhi-long; Qiu, Bi-tao; Su, Xing-wen; Yang, Huan-ming; Zhang, Guo-jie; Yan, Guang-mei; Zhou, Qi

    2016-01-01

    Snakes have numerous features distinctive from other tetrapods and a rich history of genome evolution that is still obscure. Here, we report the high-quality genome of the five-pacer viper, Deinagkistrodon acutus, and comparative analyses with other representative snake and lizard genomes. We map the evolutionary trajectories of transposable elements (TEs), developmental genes and sex chromosomes onto the snake phylogeny. TEs exhibit dynamic lineage-specific expansion, and many viper TEs show brain-specific gene expression along with their nearby genes. We detect signatures of adaptive evolution in olfactory, venom and thermal-sensing genes and also functional degeneration of genes associated with vision and hearing. Lineage-specific relaxation of functional constraints on respective Hox and Tbx limb-patterning genes supports fossil evidence for a successive loss of forelimbs then hindlimbs during snake evolution. Finally, we infer that the ZW sex chromosome pair had undergone at least three recombination suppression events in the ancestor of advanced snakes. These results altogether forge a framework for our deep understanding into snakes' history of molecular evolution. PMID:27708285

  9. Genome-wide single-generation signatures of local selection in the panmictic European eel

    DEFF Research Database (Denmark)

    Pujolar, J. M.; Jacobsen, M. W.; Als, Thomas Damm

    2014-01-01

    –receptor interaction and circadian rhythm. Remarkably, one of the candidate genes identified is PERIOD, possibly related to differences in local photoperiod associated with the >30° difference in latitude between locations. Genes under selection were spread across the genome, and there were no large regions...

  10. Genome-wide detection of signatures of selection in Korean Hanwoo cattle

    Science.gov (United States)

    The Korean Hanwoo cattle have been intensively selected for production traits, especially high intramuscular fat content. It is believed that ancient crossings between different breeds contributed to forming the Hanwoo, but little is known about the genomic differences and similarities between other...

  11. Genetic diversity and signatures of selection in various goat breeds revealed by genome-wide SNP markers.

    Science.gov (United States)

    Brito, Luiz F; Kijas, James W; Ventura, Ricardo V; Sargolzaei, Mehdi; Porto-Neto, Laercio R; Cánovas, Angela; Feng, Zeny; Jafarikia, Mohsen; Schenkel, Flávio S

    2017-03-14

    The detection of signatures of selection has the potential to elucidate the identities of genes and mutations associated with phenotypic traits important for livestock species. It is also very relevant to investigate the levels of genetic diversity of a population, as genetic diversity represents the raw material essential for breeding and has practical implications for implementation of genomic selection. A total of 1151 animals from nine goat populations selected for different breeding goals and genotyped with the Illumina Goat 50K single nucleotide polymorphisms (SNP) Beadchip were included in this investigation. The proportion of polymorphic SNPs ranged from 0.902 (Nubian) to 0.995 (Rangeland). The overall mean H O and H E was 0.374 ± 0.021 and 0.369 ± 0.023, respectively. The average pairwise genetic distance (D) ranged from 0.263 (Toggenburg) to 0.323 (Rangeland). The overall average for the inbreeding measures F EH , F VR , F LEUT , F ROH and F PED was 0.129, -0.012, -0.010, 0.038 and 0.030, respectively. Several regions located on 19 chromosomes were potentially under selection in at least one of the goat breeds. The genomic population tree constructed using all SNPs differentiated breeds based on selection purpose, while genomic population tree built using only SNPs in the most significant region showed a great differentiation between LaMancha and the other breeds. We hypothesized that this region is related to ear morphogenesis. Furthermore, we identified genes potentially related to reproduction traits, adult body mass, efficiency of food conversion, abdominal fat deposition, conformation traits, liver fat metabolism, milk fatty acids, somatic cells score, milk protein, thermo-tolerance and ear morphogenesis. In general, moderate to high levels of genetic variability were observed for all the breeds and a characterization of runs of homozygosity gave insights into the breeds' development history. The information reported here will be useful for

  12. Integrated genomics identifies five medulloblastoma subtypes with distinct genetic profiles, pathway signatures and clinicopathological features.

    Directory of Open Access Journals (Sweden)

    Marcel Kool

    Full Text Available BACKGROUND: Medulloblastoma is the most common malignant brain tumor in children. Despite recent improvements in cure rates, prediction of disease outcome remains a major challenge and survivors suffer from serious therapy-related side-effects. Recent data showed that patients with WNT-activated tumors have a favorable prognosis, suggesting that these patients could be treated less intensively, thereby reducing the side-effects. This illustrates the potential benefits of a robust classification of medulloblastoma patients and a detailed knowledge of associated biological mechanisms. METHODS AND FINDINGS: To get a better insight into the molecular biology of medulloblastoma we established mRNA expression profiles of 62 medulloblastomas and analyzed 52 of them also by comparative genomic hybridization (CGH arrays. Five molecular subtypes were identified, characterized by WNT signaling (A; 9 cases, SHH signaling (B; 15 cases, expression of neuronal differentiation genes (C and D; 16 and 11 cases, respectively or photoreceptor genes (D and E; both 11 cases. Mutations in beta-catenin were identified in all 9 type A tumors, but not in any other tumor. PTCH1 mutations were exclusively identified in type B tumors. CGH analysis identified several fully or partly subtype-specific chromosomal aberrations. Monosomy of chromosome 6 occurred only in type A tumors, loss of 9q mostly occurred in type B tumors, whereas chromosome 17 aberrations, most common in medulloblastoma, were strongly associated with type C or D tumors. Loss of the inactivated X-chromosome was highly specific for female cases of type C, D and E tumors. Gene expression levels faithfully reflected the chromosomal copy number changes. Clinicopathological features significantly different between the 5 subtypes included metastatic disease and age at diagnosis and histology. Metastatic disease at diagnosis was significantly associated with subtypes C and D and most strongly with subtype E

  13. Genomic Signatures of Selective Pressures and Introgression from Archaic Hominins at Human Innate Immunity Genes.

    Science.gov (United States)

    Deschamps, Matthieu; Laval, Guillaume; Fagny, Maud; Itan, Yuval; Abel, Laurent; Casanova, Jean-Laurent; Patin, Etienne; Quintana-Murci, Lluis

    2016-01-07

    Human genes governing innate immunity provide a valuable tool for the study of the selective pressure imposed by microorganisms on host genomes. A comprehensive, genome-wide study of how selective constraints and adaptations have driven the evolution of innate immunity genes is missing. Using full-genome sequence variation from the 1000 Genomes Project, we first show that innate immunity genes have globally evolved under stronger purifying selection than the remainder of protein-coding genes. We identify a gene set under the strongest selective constraints, mutations in which are likely to predispose individuals to life-threatening disease, as illustrated by STAT1 and TRAF3. We then evaluate the occurrence of local adaptation and detect 57 high-scoring signals of positive selection at innate immunity genes, variation in which has been associated with susceptibility to common infectious or autoimmune diseases. Furthermore, we show that most adaptations targeting coding variation have occurred in the last 6,000-13,000 years, the period at which populations shifted from hunting and gathering to farming. Finally, we show that innate immunity genes present higher Neandertal introgression than the remainder of the coding genome. Notably, among the genes presenting the highest Neandertal ancestry, we find the TLR6-TLR1-TLR10 cluster, which also contains functional adaptive variation in Europeans. This study identifies highly constrained genes that fulfill essential, non-redundant functions in host survival and reveals others that are more permissive to change-containing variation acquired from archaic hominins or adaptive variants in specific populations-improving our understanding of the relative biological importance of innate immunity pathways in natural conditions. Copyright © 2016 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  14. Complete genomes reveal signatures of demographic and genetic declines in the woolly mammoth

    Science.gov (United States)

    Palkopoulou, Eleftheria; Mallick, Swapan; Skoglund, Pontus; Enk, Jacob; Rohland, Nadin; Li, Heng; Omrak, Ayça; Vartanyan, Sergey; Poinar, Hendrik; Götherström, Anders; Reich, David; Dalén, Love

    2015-01-01

    Summary The processes leading up to species extinctions are typically characterized by prolonged declines in population size and geographic distribution, followed by a phase in which populations are very small and may be subject to intrinsic threats, including loss of genetic diversity and inbreeding [1]. However, whether such genetic factors have had an impact on species prior to their extinction is unclear [2, 3]; examining this would require a detailed reconstruction of a species’ demographic history as well as changes in genome-wide diversity leading up to its extinction. Here, we present high-quality complete genome sequences from two woolly mammoths (Mammuthus primigenius). The first mammoth was sequenced at 17.1-fold coverage, and dates to ~4,300 years before present, constituting one of the last surviving individuals on Wrangel Island. The second mammoth, sequenced at 11.2-fold coverage, was obtained from a ~44,800 year old specimen from the Late Pleistocene population in northeastern Siberia. The demographic trajectories inferred from the two genomes are qualitatively similar and reveal a population bottleneck during the Middle or Early Pleistocene, and a more recent severe decline in the ancestors of the Wrangel mammoth at the end of the last glaciation. A comparison of the two genomes shows that the Wrangel mammoth has a 20% reduction in heterozygosity as well as a 28-fold increase in the fraction of the genome that is comprised of runs of homozygosity. We conclude that the population on Wrangel Island, which was the last surviving woolly mammoth population, was subject to reduced genetic diversity shortly before it became extinct. PMID:25913407

  15. Genomic characteristics and comparative genomics analysis of Penicillium chrysogenum KF-25.

    Science.gov (United States)

    Peng, Qin; Yuan, Yihui; Gao, Meiying; Chen, Xupeng; Liu, Biao; Liu, Pengming; Wu, Yan; Wu, Dandan

    2014-02-21

    Penicillium chrysogenum has been used in producing penicillin and derived β-lactam antibiotics for many years. Although the genome of the mutant strain P. chrysogenum Wisconsin 54-1255 has already been sequenced, the versatility and genetic diversity of this species still needs to be intensively studied. In this study, the genome of the wild-type P. chrysogenum strain KF-25, which has high activity against Ustilaginoidea virens, was sequenced and characterized. The genome of KF-25 was about 29.9 Mb in size and contained 9,804 putative open reading frames (orfs). Thirteen genes were predicted to encode two-component system proteins, of which six were putatively involved in osmolarity adaption. There were 33 putative secondary metabolism pathways and numerous genes that were essential in metabolite biosynthesis. Several P. chrysogenum virus untranslated region sequences were found in the KF-25 genome, suggesting that there might be a relationship between the virus and P. chrysogenum in evolution. Comparative genome analysis showed that the genomes of KF-25 and Wisconsin 54-1255 were highly similar, except that KF-25 was 2.3 Mb smaller. Three hundred and fifty-five KF-25 specific genes were found and the biological functions of the proteins encoded by these genes were mainly unknown (232, representing 65%), except for some orfs encoding proteins with predicted functions in transport, metabolism, and signal transduction. Numerous KF-25-specific genes were found to be associated with the pathogenicity and virulence of the strains, which were identical to those of wild-type P. chrysogenum NRRL 1951. Genome sequencing and comparative analysis are helpful in further understanding the biology, evolution, and environment adaption of P. chrysogenum, and provide a new tool for identifying further functional metabolites.

  16. Genomic profiling of oral squamous cell carcinoma by array-based comparative genomic hybridization.

    Directory of Open Access Journals (Sweden)

    Shunichi Yoshioka

    Full Text Available We designed a study to investigate genetic relationships between primary tumors of oral squamous cell carcinoma (OSCC and their lymph node metastases, and to identify genomic copy number aberrations (CNAs related to lymph node metastasis. For this purpose, we collected a total of 42 tumor samples from 25 patients and analyzed their genomic profiles by array-based comparative genomic hybridization. We then compared the genetic profiles of metastatic primary tumors (MPTs with their paired lymph node metastases (LNMs, and also those of LNMs with non-metastatic primary tumors (NMPTs. Firstly, we found that although there were some distinctive differences in the patterns of genomic profiles between MPTs and their paired LNMs, the paired samples shared similar genomic aberration patterns in each case. Unsupervised hierarchical clustering analysis grouped together 12 of the 15 MPT-LNM pairs. Furthermore, similarity scores between paired samples were significantly higher than those between non-paired samples. These results suggested that MPTs and their paired LNMs are composed predominantly of genetically clonal tumor cells, while minor populations with different CNAs may also exist in metastatic OSCCs. Secondly, to identify CNAs related to lymph node metastasis, we compared CNAs between grouped samples of MPTs and LNMs, but were unable to find any CNAs that were more common in LNMs. Finally, we hypothesized that subpopulations carrying metastasis-related CNAs might be present in both the MPT and LNM. Accordingly, we compared CNAs between NMPTs and LNMs, and found that gains of 7p, 8q and 17q were more common in the latter than in the former, suggesting that these CNAs may be involved in lymph node metastasis of OSCC. In conclusion, our data suggest that in OSCCs showing metastasis, the primary and metastatic tumors share similar genomic profiles, and that cells in the primary tumor may tend to metastasize after acquiring metastasis-associated CNAs.

  17. Genomic profiling of oral squamous cell carcinoma by array-based comparative genomic hybridization.

    Science.gov (United States)

    Yoshioka, Shunichi; Tsukamoto, Yoshiyuki; Hijiya, Naoki; Nakada, Chisato; Uchida, Tomohisa; Matsuura, Keiko; Takeuchi, Ichiro; Seto, Masao; Kawano, Kenji; Moriyama, Masatsugu

    2013-01-01

    We designed a study to investigate genetic relationships between primary tumors of oral squamous cell carcinoma (OSCC) and their lymph node metastases, and to identify genomic copy number aberrations (CNAs) related to lymph node metastasis. For this purpose, we collected a total of 42 tumor samples from 25 patients and analyzed their genomic profiles by array-based comparative genomic hybridization. We then compared the genetic profiles of metastatic primary tumors (MPTs) with their paired lymph node metastases (LNMs), and also those of LNMs with non-metastatic primary tumors (NMPTs). Firstly, we found that although there were some distinctive differences in the patterns of genomic profiles between MPTs and their paired LNMs, the paired samples shared similar genomic aberration patterns in each case. Unsupervised hierarchical clustering analysis grouped together 12 of the 15 MPT-LNM pairs. Furthermore, similarity scores between paired samples were significantly higher than those between non-paired samples. These results suggested that MPTs and their paired LNMs are composed predominantly of genetically clonal tumor cells, while minor populations with different CNAs may also exist in metastatic OSCCs. Secondly, to identify CNAs related to lymph node metastasis, we compared CNAs between grouped samples of MPTs and LNMs, but were unable to find any CNAs that were more common in LNMs. Finally, we hypothesized that subpopulations carrying metastasis-related CNAs might be present in both the MPT and LNM. Accordingly, we compared CNAs between NMPTs and LNMs, and found that gains of 7p, 8q and 17q were more common in the latter than in the former, suggesting that these CNAs may be involved in lymph node metastasis of OSCC. In conclusion, our data suggest that in OSCCs showing metastasis, the primary and metastatic tumors share similar genomic profiles, and that cells in the primary tumor may tend to metastasize after acquiring metastasis-associated CNAs.

  18. G-compass: a web-based comparative genome browser between human and other vertebrate genomes.

    Science.gov (United States)

    Kawahara, Yoshihiro; Sakate, Ryuichi; Matsuya, Akihiro; Murakami, Katsuhiko; Sato, Yoshiharu; Zhang, Hao; Gojobori, Takashi; Itoh, Takeshi; Imanishi, Tadashi

    2009-12-15

    G-compass is designed for efficient comparative genome analysis between human and other vertebrate genomes. The current version of G-compass allows us to browse two corresponding genomic regions between human and another species in parallel. One-to-one evolutionarily conserved regions (i.e. orthologous regions) between species are highlighted along the genomes. Information such as locations of duplicated regions, copy number variations and mammalian ultra-conserved elements is also provided. These features of G-compass enable us to easily determine patterns of genomic rearrangements and changes in gene orders through evolutionary time. Since G-compass is a satellite database of H-InvDB, which is a comprehensive annotation resource for human genes and transcripts, users can easily refer to manually curated functional annotations and other abundant biological information for each human transcript. G-compass is expected to be a valuable tool for comparing human and model organisms and promoting the exchange of functional information. G-compass is freely available at http://www.h-invitational.jp/g-compass/. t.imanishi@aist.go.jp

  19. Genome analysis and comparative genomics of a Giardia intestinalis assemblage E isolate

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    Andersson Jan O

    2010-10-01

    Full Text Available Abstract Background Giardia intestinalis is a protozoan parasite that causes diarrhea in a wide range of mammalian species. To further understand the genetic diversity between the Giardia intestinalis species, we have performed genome sequencing and analysis of a wild-type Giardia intestinalis sample from the assemblage E group, isolated from a pig. Results We identified 5012 protein coding genes, the majority of which are conserved compared to the previously sequenced genomes of the WB and GS strains in terms of microsynteny and sequence identity. Despite this, there is an unexpectedly large number of chromosomal rearrangements and several smaller structural changes that are present in all chromosomes. Novel members of the VSP, NEK Kinase and HCMP gene families were identified, which may reveal possible mechanisms for host specificity and new avenues for antigenic variation. We used comparative genomics of the three diverse Giardia intestinalis isolates P15, GS and WB to define a core proteome for this species complex and to identify lineage-specific genes. Extensive analyses of polymorphisms in the core proteome of Giardia revealed differential rates of divergence among cellular processes. Conclusions Our results indicate that despite a well conserved core of genes there is significant genome variation between Giardia isolates, both in terms of gene content, gene polymorphisms, structural chromosomal variations and surface molecule repertoires. This study improves the annotation of the Giardia genomes and enables the identification of functionally important variation.

  20. Presence–Absence Variation in A. thaliana Is Primarily Associated with Genomic Signatures Consistent with Relaxed Selective Constraints

    Science.gov (United States)

    Bush, Stephen J.; Castillo-Morales, Atahualpa; Tovar-Corona, Jaime M.; Chen, Lu; Kover, Paula X.; Urrutia, Araxi O.

    2014-01-01

    The sequencing of multiple genomes of the same plant species has revealed polymorphic gene and exon loss. Genes associated with disease resistance are overrepresented among those showing structural variations, suggesting an adaptive role for gene and exon presence–absence variation (PAV). To shed light on the possible functional relevance of polymorphic coding region loss and the mechanisms driving this process, we characterized genes that have lost entire exons or their whole coding regions in 17 fully sequenced Arabidopsis thaliana accessions. We found that although a significant enrichment in genes associated with certain functional categories is observed, PAV events are largely restricted to genes with signatures of reduced essentiality: PAV genes tend to be newer additions to the genome, tissue specific, and lowly expressed. In addition, PAV genes are located in regions of lower gene density and higher transposable element density. Partial coding region PAV events were associated with only a marginal reduction in gene expression level in the affected accession and occurred in genes with higher levels of alternative splicing in the Col-0 accession. Together, these results suggest that although adaptive scenarios cannot be ruled out, PAV events can be explained without invoking them. PMID:24072814

  1. Floral gene resources from basal angiosperms for comparative genomics research

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    Zhang Xiaohong

    2005-03-01

    Full Text Available Abstract Background The Floral Genome Project was initiated to bridge the genomic gap between the most broadly studied plant model systems. Arabidopsis and rice, although now completely sequenced and under intensive comparative genomic investigation, are separated by at least 125 million years of evolutionary time, and cannot in isolation provide a comprehensive perspective on structural and functional aspects of flowering plant genome dynamics. Here we discuss new genomic resources available to the scientific community, comprising cDNA libraries and Expressed Sequence Tag (EST sequences for a suite of phylogenetically basal angiosperms specifically selected to bridge the evolutionary gaps between model plants and provide insights into gene content and genome structure in the earliest flowering plants. Results Random sequencing of cDNAs from representatives of phylogenetically important eudicot, non-grass monocot, and gymnosperm lineages has so far (as of 12/1/04 generated 70,514 ESTs and 48,170 assembled unigenes. Efficient sorting of EST sequences into putative gene families based on whole Arabidopsis/rice proteome comparison has permitted ready identification of cDNA clones for finished sequencing. Preliminarily, (i proportions of functional categories among sequenced floral genes seem representative of the entire Arabidopsis transcriptome, (ii many known floral gene homologues have been captured, and (iii phylogenetic analyses of ESTs are providing new insights into the process of gene family evolution in relation to the origin and diversification of the angiosperms. Conclusion Initial comparisons illustrate the utility of the EST data sets toward discovery of the basic floral transcriptome. These first findings also afford the opportunity to address a number of conspicuous evolutionary genomic questions, including reproductive organ transcriptome overlap between angiosperms and gymnosperms, genome-wide duplication history, lineage

  2. Comparative analysis of Acinetobacters: three genomes for three lifestyles.

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    David Vallenet

    Full Text Available Acinetobacter baumannii is the source of numerous nosocomial infections in humans and therefore deserves close attention as multidrug or even pandrug resistant strains are increasingly being identified worldwide. Here we report the comparison of two newly sequenced genomes of A. baumannii. The human isolate A. baumannii AYE is multidrug resistant whereas strain SDF, which was isolated from body lice, is antibiotic susceptible. As reference for comparison in this analysis, the genome of the soil-living bacterium A. baylyi strain ADP1 was used. The most interesting dissimilarities we observed were that i whereas strain AYE and A. baylyi genomes harbored very few Insertion Sequence elements which could promote expression of downstream genes, strain SDF sequence contains several hundred of them that have played a crucial role in its genome reduction (gene disruptions and simple DNA loss; ii strain SDF has low catabolic capacities compared to strain AYE. Interestingly, the latter has even higher catabolic capacities than A. baylyi which has already been reported as a very nutritionally versatile organism. This metabolic performance could explain the persistence of A. baumannii nosocomial strains in environments where nutrients are scarce; iii several processes known to play a key role during host infection (biofilm formation, iron uptake, quorum sensing, virulence factors were either different or absent, the best example of which is iron uptake. Indeed, strain AYE and A. baylyi use siderophore-based systems to scavenge iron from the environment whereas strain SDF uses an alternate system similar to the Haem Acquisition System (HAS. Taken together, all these observations suggest that the genome contents of the 3 Acinetobacters compared are partly shaped by life in distinct ecological niches: human (and more largely hospital environment, louse, soil.

  3. Selection Signatures in the First Exon of Paralogous Receptor Kinase Genes from the Sym2 Region of the Pisum sativum L. Genome

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    Anton S. Sulima

    2017-11-01

    Full Text Available During the initial step of the symbiosis between legumes (Fabaceae and nitrogen-fixing bacteria (rhizobia, the bacterial signal molecule known as the Nod factor (nodulation factor is recognized by plant LysM motif-containing receptor-like kinases (LysM-RLKs. The fifth chromosome of barrel medic (Medicago truncatula Gaertn. contains a cluster of paralogous LysM-RLK genes, one of which is known to participate in symbiosis. In the syntenic region of the pea (Pisum sativum L. genome, three genes have been identified: PsK1 and PsSym37, two symbiosis-related LysM-RLK genes with known sequences, and the unsequenced PsSym2 gene which presumably encodes a LysM-RLK and is associated with increased selectivity to certain Nod factors. In this work, we identified a new gene encoding a LysM-RLK, designated as PsLykX, within the Sym2 genomic region. We sequenced the first exons (corresponding to the protein receptor domain of PsSym37, PsK1, and PsLykX from a large set of pea genotypes of diverse origin. The nucleotide diversity of these fragments was estimated and groups of haplotypes for each gene were revealed. Footprints of selection pressure were detected via comparative analyses of SNP distribution across the first exons of these genes and their homologs MtLYK2, MtLYK3, and MtLYK4 from M. truncatula retrieved from the Medicago Hapmap project. Despite the remarkable similarity among all the studied genes, they exhibited contrasting selection signatures, possibly pointing to diversification of their functions. Signatures of balancing selection were found in LysM1-encoding parts of PsSym37 and PsK1, suggesting that the diversity of these parts may be important for pea LysM-RLKs. The first exons of PsSym37 and PsK1 displayed signatures of purifying selection, as well as MtLYK2 of M. truncatula. Evidence of positive selection affecting primarily LysM domains was found in all three investigated M. truncatula genes, as well as in the pea gene PsLykX. The data

  4. Classical Oncogenes and Tumor Suppressor Genes: A Comparative Genomics Perspective

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    Oxana K. Pickeral

    2000-05-01

    Full Text Available We have curated a reference set of cancer-related genes and reanalyzed their sequences in the light of molecular information and resources that have become available since they were first cloned. Homology studies were carried out for human oncogenes and tumor suppressors, compared with the complete proteome of the nematode, Caenorhabditis elegans, and partial proteomes of mouse and rat and the fruit fly, Drosophila melanogaster. Our results demonstrate that simple, semi-automated bioinformatics approaches to identifying putative functionally equivalent gene products in different organisms may often be misleading. An electronic supplement to this article1 provides an integrated view of our comparative genomics analysis as well as mapping data, physical cDNA resources and links to published literature and reviews, thus creating a “window” into the genomes of humans and other organisms for cancer biology.

  5. Microarray comparative genomic hybridisation analysis incorporating genomic organisation, and application to enterobacterial plant pathogens.

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    Leighton Pritchard

    2009-08-01

    Full Text Available Microarray comparative genomic hybridisation (aCGH provides an estimate of the relative abundance of genomic DNA (gDNA taken from comparator and reference organisms by hybridisation to a microarray containing probes that represent sequences from the reference organism. The experimental method is used in a number of biological applications, including the detection of human chromosomal aberrations, and in comparative genomic analysis of bacterial strains, but optimisation of the analysis is desirable in each problem domain.We present a method for analysis of bacterial aCGH data that encodes spatial information from the reference genome in a hidden Markov model. This technique is the first such method to be validated in comparisons of sequenced bacteria that diverge at the strain and at the genus level: Pectobacterium atrosepticum SCRI1043 (Pba1043 and Dickeya dadantii 3937 (Dda3937; and Lactococcus lactis subsp. lactis IL1403 and L. lactis subsp. cremoris MG1363. In all cases our method is found to outperform common and widely used aCGH analysis methods that do not incorporate spatial information. This analysis is applied to comparisons between commercially important plant pathogenic soft-rotting enterobacteria (SRE Pba1043, P. atrosepticum SCRI1039, P. carotovorum 193, and Dda3937.Our analysis indicates that it should not be assumed that hybridisation strength is a reliable proxy for sequence identity in aCGH experiments, and robustly extends the applicability of aCGH to bacterial comparisons at the genus level. Our results in the SRE further provide evidence for a dynamic, plastic 'accessory' genome, revealing major genomic islands encoding gene products that provide insight into, and may play a direct role in determining, variation amongst the SRE in terms of their environmental survival, host range and aetiology, such as phytotoxin synthesis, multidrug resistance, and nitrogen fixation.

  6. Whole-genome scanning by array comparative genomic hybridization as a clinical tool for risk assessment in chronic lymphocytic leukemia

    NARCIS (Netherlands)

    Gunn, Shelly R.; Mohammed, Mansoor S.; Gorre, Mercedes E.; Cotter, Philip D.; Kim, Jaeweon; Bahler, David W.; Preobrazhensky, Sergey N.; Higgins, Russell A.; Bolla, Aswani R.; Ismail, Sahar H.; de Jong, Daphne; Eldering, Eric; van Oers, Marinus H. J.; Mellink, Clemens H. M.; Keating, Michael J.; Schlette, Ellen J.; Abruzzo, Lynne V.; Robetorye, Ryan S.

    2008-01-01

    Array-based comparative genomic hybridization (array CGH) provides a powerful method for simultaneous genome-wide scanning and prognostic marker assessment in chronic lymphocytic leukemia (CLL). In the current study, commercially available bacterial artificial chromosome and oligonucleotide array

  7. Using comparative genomics to decode the genetics of acaricide resistance.

    Science.gov (United States)

    Van Zee, Janice P; Hill, Catherine A

    2018-01-01

    The availability of genome assemblies and other genomic resources is facilitating investigations of complex genetic traits for several species of ticks. Understanding the genetics of acaricide resistance is a priority for tick and tick-borne disease control. The synaptic enzyme acetylcholinesterase (ACE) is recognized as the target of organophosphates (OPs) and carbamates, and mutations in ACE have been tied to resistance. Multiple studies support three ACE (ace) loci in R. microplus but the molecular basis of OP-resistance in this tick remains elusive. Here, we exploited the genome assembly of the black-legged tick Ixodes scapularis and comparative genomic analyses to explore the complement of tick ACEs and their potential roles in OP resistance. We identified eight putative ace loci ( IscaACE1a, 1b, 2a-c, 3a-c ) in I. scapularis. Molecular analyses and homology modeling suggest ACE activity for IscaACE1a. Our analyses reveal the molecular complexity of the I. scapularis ace gene family, highlight the need for functional studies of ACEs in species of the Ixodidae, and reveal potential challenges to management of OP resistance in ticks.

  8. Comparative genomic analysis as a tool for biological discovery.

    Science.gov (United States)

    Nobrega, Marcelo A; Pennacchio, Len A

    2004-01-01

    The recent completion of the human genome sequence has enabled the identification of a large fraction of our gene catalogue and their physical chromosomal position. However, current efforts lag at defining the cis-regulatory sequences that control the spatial and temporal patterns of each gene's expression. This task remains difficult due to our lack of knowledge of the vocabulary controlling gene regulation and the vast genomic search space, with greater than 95% of our genome being noncoding. Recent comparative genomic-based strategies are beginning to aid in the identification of functional sequences based on their high levels of evolutionary conservation. This has proven successful for comparisons between closely related species such as human-primate or human-mouse, but also holds true for distant evolutionary comparisons, such as human-fish or human-bird. In this review we provide support for the utility of cross-species sequence comparisons by illustrating several applications of this strategy, including the identification of new genes and functional non-coding sequences. We also discuss emerging concepts as this field matures, such as how to properly select which species for comparison, which may differ significantly between independent studies.

  9. The genome sequence of Caenorhabditis briggsae: a platform for comparative genomics.

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    Lincoln D Stein

    2003-11-01

    Full Text Available The soil nematodes Caenorhabditis briggsae and Caenorhabditis elegans diverged from a common ancestor roughly 100 million years ago and yet are almost indistinguishable by eye. They have the same chromosome number and genome sizes, and they occupy the same ecological niche. To explore the basis for this striking conservation of structure and function, we have sequenced the C. briggsae genome to a high-quality draft stage and compared it to the finished C. elegans sequence. We predict approximately 19,500 protein-coding genes in the C. briggsae genome, roughly the same as in C. elegans. Of these, 12,200 have clear C. elegans orthologs, a further 6,500 have one or more clearly detectable C. elegans homologs, and approximately 800 C. briggsae genes have no detectable matches in C. elegans. Almost all of the noncoding RNAs (ncRNAs known are shared between the two species. The two genomes exhibit extensive colinearity, and the rate of divergence appears to be higher in the chromosomal arms than in the centers. Operons, a distinctive feature of C. elegans, are highly conserved in C. briggsae, with the arrangement of genes being preserved in 96% of cases. The difference in size between the C. briggsae (estimated at approximately 104 Mbp and C. elegans (100.3 Mbp genomes is almost entirely due to repetitive sequence, which accounts for 22.4% of the C. briggsae genome in contrast to 16.5% of the C. elegans genome. Few, if any, repeat families are shared, suggesting that most were acquired after the two species diverged or are undergoing rapid evolution. Coclustering the C. elegans and C. briggsae proteins reveals 2,169 protein families of two or more members. Most of these are shared between the two species, but some appear to be expanding or contracting, and there seem to be as many as several hundred novel C. briggsae gene families. The C. briggsae draft sequence will greatly improve the annotation of the C. elegans genome. Based on similarity to C

  10. Polar Bears Exhibit Genome-Wide Signatures of Bioenergetic Adaptation to Life in the Arctic Environment

    OpenAIRE

    Welch, Andreanna J.; Bedoya-Reina, Oscar C.; Carretero-Paulet, Lorenzo; Miller, Webb; Rode, Karyn D.; Lindqvist, Charlotte

    2014-01-01

    Polar bears (Ursus maritimus) face extremely cold temperatures and periods of fasting, which might result in more severe energetic challenges than those experienced by their sister species, the brown bear (U. arctos). We have examined the mitochondrial and nuclear genomes of polar and brown bears to investigate whether polar bears demonstrate lineage-specific signals of molecular adaptation in genes associated with cellular respiration/energy production. We observed increased evolutionary rat...

  11. Genomic signature of successful colonization of Eurasia by the allopolyploid shepherd's purse (Capsella bursa-pastoris).

    Science.gov (United States)

    Cornille, A; Salcedo, A; Kryvokhyzha, D; Glémin, S; Holm, K; Wright, S I; Lascoux, M

    2016-01-01

    Polyploidization is a dominant feature of flowering plant evolution. However, detailed genomic analyses of the interpopulation diversification of polyploids following genome duplication are still in their infancy, mainly because of methodological limits, both in terms of sequencing and computational analyses. The shepherd's purse (Capsella bursa-pastoris) is one of the most common weed species in the world. It is highly self-fertilizing, and recent genomic data indicate that it is an allopolyploid, resulting from hybridization between the ancestors of the diploid species Capsella grandiflora and Capsella orientalis. Here, we investigated the genomic diversity of C. bursa-pastoris, its population structure and demographic history, following allopolyploidization in Eurasia. To that end, we genotyped 261 C. bursa-pastoris accessions spread across Europe, the Middle East and Asia, using genotyping-by-sequencing, leading to a total of 4274 SNPs after quality control. Bayesian clustering analyses revealed three distinct genetic clusters in Eurasia: one cluster grouping samples from Western Europe and Southeastern Siberia, the second one centred on Eastern Asia and the third one in the Middle East. Approximate Bayesian computation (ABC) supported the hypothesis that C. bursa-pastoris underwent a typical colonization history involving low gene flow among colonizing populations, likely starting from the Middle East towards Europe and followed by successive human-mediated expansions into Eastern Asia. Altogether, these findings bring new insights into the recent multistage colonization history of the allotetraploid C. bursa-pastoris and highlight ABC and genotyping-by-sequencing data as promising but still challenging tools to infer demographic histories of selfing allopolyploids. © 2015 John Wiley & Sons Ltd.

  12. Advanced Cancer Genomics Institute: Genetic Signatures and Therapeutic Targets in Cancer Progression

    Science.gov (United States)

    2014-02-01

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  13. Diversity of Pseudomonas Genomes, Including Populus-Associated Isolates, as Revealed by Comparative Genome Analysis.

    Science.gov (United States)

    Jun, Se-Ran; Wassenaar, Trudy M; Nookaew, Intawat; Hauser, Loren; Wanchai, Visanu; Land, Miriam; Timm, Collin M; Lu, Tse-Yuan S; Schadt, Christopher W; Doktycz, Mitchel J; Pelletier, Dale A; Ussery, David W

    2016-01-01

    The Pseudomonas genus contains a metabolically versatile group of organisms that are known to occupy numerous ecological niches, including the rhizosphere and endosphere of many plants. Their diversity influences the phylogenetic diversity and heterogeneity of these communities. On the basis of average amino acid identity, comparative genome analysis of >1,000 Pseudomonas genomes, including 21 Pseudomonas strains isolated from the roots of native Populus deltoides (eastern cottonwood) trees resulted in consistent and robust genomic clusters with phylogenetic homogeneity. All Pseudomonas aeruginosa genomes clustered together, and these were clearly distinct from other Pseudomonas species groups on the basis of pangenome and core genome analyses. In contrast, the genomes of Pseudomonas fluorescens were organized into 20 distinct genomic clusters, representing enormous diversity and heterogeneity. Most of our 21 Populus-associated isolates formed three distinct subgroups within the major P. fluorescens group, supported by pathway profile analysis, while two isolates were more closely related to Pseudomonas chlororaphis and Pseudomonas putida. Genes specific to Populus-associated subgroups were identified. Genes specific to subgroup 1 include several sensory systems that act in two-component signal transduction, a TonB-dependent receptor, and a phosphorelay sensor. Genes specific to subgroup 2 contain hypothetical genes, and genes specific to subgroup 3 were annotated with hydrolase activity. This study justifies the need to sequence multiple isolates, especially from P. fluorescens, which displays the most genetic variation, in order to study functional capabilities from a pangenomic perspective. This information will prove useful when choosing Pseudomonas strains for use to promote growth and increase disease resistance in plants. Copyright © 2015 Jun et al.

  14. Draft genome sequence of Cellulomonas carbonis T26(T) and comparative analysis of six Cellulomonas genomes.

    Science.gov (United States)

    Zhuang, Weiping; Zhang, Shengzhe; Xia, Xian; Wang, Gejiao

    2015-01-01

    Most Cellulomonas strains are cellulolytic and this feature may be applied in straw degradation and bioremediation. In this study, Cellulomonas carbonis T26(T), Cellulomonas bogoriensis DSM 16987(T) and Cellulomonas cellasea 20108(T) were sequenced. Here we described the draft genomic information of C. carbonis T26(T) and compared it to the related Cellulomonas genomes. Strain T26(T) has a 3,990,666 bp genome size with a G + C content of 73.4 %, containing 3418 protein-coding genes and 59 RNA genes. The results showed good correlation between the genotypes and the physiological phenotypes. The information are useful for the better application of the Cellulomonas strains.

  15. The genome sequence of Blochmannia floridanus: Comparative analysis of reduced genomes

    Science.gov (United States)

    Gil, Rosario; Silva, Francisco J.; Zientz, Evelyn; Delmotte, François; González-Candelas, Fernando; Latorre, Amparo; Rausell, Carolina; Kamerbeek, Judith; Gadau, Jürgen; Hölldobler, Bert; van Ham, Roeland C. H. J.; Gross, Roy; Moya, Andrés

    2003-01-01

    Bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. We present the complete genome sequence of Blochmannia floridanus, the primary endosymbiont of carpenter ants. Although these ants feed on a complex diet, this symbiosis very likely has a nutritional basis: Blochmannia is able to supply nitrogen and sulfur compounds to the host while it takes advantage of the host metabolic machinery. Remarkably, these bacteria lack all known genes involved in replication initiation (dnaA, priA, and recA). The phylogenetic analysis of a set of conserved protein-coding genes shows that Bl. floridanus is phylogenetically related to Buchnera aphidicola and Wigglesworthia glossinidia, the other endosymbiotic bacteria whose complete genomes have been sequenced so far. Comparative analysis of the five known genomes from insect endosymbiotic bacteria reveals they share only 313 genes, a number that may be close to the minimum gene set necessary to sustain endosymbiotic life. PMID:12886019

  16. Comparative genome analysis of Bacillus cereus group genomes withBacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain; Sorokin, Alexei; Kapatral, Vinayak; Reznik, Gary; Bhattacharya, Anamitra; Mikhailova, Natalia; Burd, Henry; Joukov, Victor; Kaznadzey, Denis; Walunas, Theresa; D' Souza, Mark; Larsen, Niels; Pusch,Gordon; Liolios, Konstantinos; Grechkin, Yuri; Lapidus, Alla; Goltsman,Eugene; Chu, Lien; Fonstein, Michael; Ehrlich, S. Dusko; Overbeek, Ross; Kyrpides, Nikos; Ivanova, Natalia

    2005-09-14

    Genome features of the Bacillus cereus group genomes (representative strains of Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis sub spp israelensis) were analyzed and compared with the Bacillus subtilis genome. A core set of 1,381 protein families among the four Bacillus genomes, with an additional set of 933 families common to the B. cereus group, was identified. Differences in signal transduction pathways, membrane transporters, cell surface structures, cell wall, and S-layer proteins suggesting differences in their phenotype were identified. The B. cereus group has signal transduction systems including a tyrosine kinase related to two-component system histidine kinases from B. subtilis. A model for regulation of the stress responsive sigma factor sigmaB in the B. cereus group different from the well studied regulation in B. subtilis has been proposed. Despite a high degree of chromosomal synteny among these genomes, significant differences in cell wall and spore coat proteins that contribute to the survival and adaptation in specific hosts has been identified.

  17. The Whole Genome Assembly and Comparative Genomic Research of Thellungiella parvula (Extremophile Crucifer Mitochondrion

    Directory of Open Access Journals (Sweden)

    Xuelin Wang

    2016-01-01

    Full Text Available The complete nucleotide sequences of the mitochondrial (mt genome of an extremophile species Thellungiella parvula (T. parvula have been determined with the lengths of 255,773 bp. T. parvula mt genome is a circular sequence and contains 32 protein-coding genes, 19 tRNA genes, and three ribosomal RNA genes with a 11.5% coding sequence. The base composition of 27.5% A, 27.5% T, 22.7% C, and 22.3% G in descending order shows a slight bias of 55% AT. Fifty-three repeats were identified in the mitochondrial genome of T. parvula, including 24 direct repeats, 28 tandem repeats (TRs, and one palindromic repeat. Furthermore, a total of 199 perfect microsatellites have been mined with a high A/T content (83.1% through simple sequence repeat (SSR analysis and they were distributed unevenly within this mitochondrial genome. We also analyzed other plant mitochondrial genomes’ evolution in general, providing clues for the understanding of the evolution of organelles genomes in plants. Comparing with other Brassicaceae species, T. parvula is related to Arabidopsis thaliana whose characters of low temperature resistance have been well documented. This study will provide important genetic tools for other Brassicaceae species research and improve yields of economically important plants.

  18. Microarray karyotyping of commercial wine yeast strains reveals shared, as well as unique, genomic signatures

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    Levine R Paul

    2005-04-01

    Full Text Available Abstract Background Genetic differences between yeast strains used in wine-making may account for some of the variation seen in their fermentation properties and may also produce differing sensory characteristics in the final wine product itself. To investigate this, we have determined genomic differences among several Saccharomyces cerevisiae wine strains by using a "microarray karyotyping" (also known as "array-CGH" or "aCGH" technique. Results We have studied four commonly used commercial wine yeast strains, assaying three independent isolates from each strain. All four wine strains showed common differences with respect to the laboratory S. cerevisiae strain S288C, some of which may be specific to commercial wine yeasts. We observed very little intra-strain variation; i.e., the genomic karyotypes of different commercial isolates of the same strain looked very similar, although an exception to this was seen among the Montrachet isolates. A moderate amount of inter-strain genomic variation between the four wine strains was observed, mostly in the form of depletions or amplifications of single genes; these differences allowed unique identification of each strain. Many of the inter-strain differences appear to be in transporter genes, especially hexose transporters (HXT genes, metal ion sensors/transporters (CUP1, ZRT1, ENA genes, members of the major facilitator superfamily, and in genes involved in drug response (PDR3, SNQ1, QDR1, RDS1, AYT1, YAR068W. We therefore used halo assays to investigate the response of these strains to three different fungicidal drugs (cycloheximide, clotrimazole, sulfomethuron methyl. Strains with fewer copies of the CUP1 loci showed hypersensitivity to sulfomethuron methyl. Conclusion Microarray karyotyping is a useful tool for analyzing the genome structures of wine yeasts. Despite only small to moderate variations in gene copy numbers between different wine yeast strains and within different isolates of a given

  19. Comparative genomics: beyond the horizon of the next research grant.

    Science.gov (United States)

    Schuit, Frans

    2015-08-01

    With the development of agriculture and food processing techniques, humanity has recently challenged the rules of a billion-year-old experiment called evolution. In this experiment the availability of food in a particular niche has been one of the major driving forces to shape particular species. Comparative genomics is a new research discipline that investigates two or more genomes from different species in order to find specific genetic adaptations that explain a 'workable match' between genetic make-up and environmental constraints such as nutrition. Three recent examples in the literature illustrate how selection of particular genes can contribute to species-specific adaptations that allow them to recognise, secure and digest particular types of food and metabolise its ingredients. There is growing consensus that the recent changes in human diet and physical activity play an active role in the rapid growth of the prevalence of obesity and diabetes. The working hypothesis of the present article is that in the future a more advanced level of comparative genomics of the many natural workable matches of natural species will lead to a much better understanding of the dynamics and regulation of integrated metabolism. It is anticipated that this deeper understanding will lead to novel insights into the mechanism of human diabetes and new strategies for diabetes prevention and treatment. This is one of a series of commentaries under the banner '50 years forward', giving personal opinions on future perspectives in diabetes, to celebrate the 50th anniversary of Diabetologia (1965-2015).

  20. Xylella fastidiosa comparative genomic database is an information resource to explore the annotation, genomic features, and biology of different strains

    Directory of Open Access Journals (Sweden)

    Alessandro M. Varani

    2012-01-01

    Full Text Available The Xylella fastidiosa comparative genomic database is a scientific resource with the aim to provide a user-friendly interface for accessing high-quality manually curated genomic annotation and comparative sequence analysis, as well as for identifying and mapping prophage-like elements, a marked feature of Xylella genomes. Here we describe a database and tools for exploring the biology of this important plant pathogen. The hallmarks of this database are the high quality genomic annotation, the functional and comparative genomic analysis and the identification and mapping of prophage-like elements. It is available from web site http://www.xylella.lncc.br.

  1. A comparative encyclopedia of DNA elements in the mouse genome.

    Science.gov (United States)

    Yue, Feng; Cheng, Yong; Breschi, Alessandra; Vierstra, Jeff; Wu, Weisheng; Ryba, Tyrone; Sandstrom, Richard; Ma, Zhihai; Davis, Carrie; Pope, Benjamin D; Shen, Yin; Pervouchine, Dmitri D; Djebali, Sarah; Thurman, Robert E; Kaul, Rajinder; Rynes, Eric; Kirilusha, Anthony; Marinov, Georgi K; Williams, Brian A; Trout, Diane; Amrhein, Henry; Fisher-Aylor, Katherine; Antoshechkin, Igor; DeSalvo, Gilberto; See, Lei-Hoon; Fastuca, Meagan; Drenkow, Jorg; Zaleski, Chris; Dobin, Alex; Prieto, Pablo; Lagarde, Julien; Bussotti, Giovanni; Tanzer, Andrea; Denas, Olgert; Li, Kanwei; Bender, M A; Zhang, Miaohua; Byron, Rachel; Groudine, Mark T; McCleary, David; Pham, Long; Ye, Zhen; Kuan, Samantha; Edsall, Lee; Wu, Yi-Chieh; Rasmussen, Matthew D; Bansal, Mukul S; Kellis, Manolis; Keller, Cheryl A; Morrissey, Christapher S; Mishra, Tejaswini; Jain, Deepti; Dogan, Nergiz; Harris, Robert S; Cayting, Philip; Kawli, Trupti; Boyle, Alan P; Euskirchen, Ghia; Kundaje, Anshul; Lin, Shin; Lin, Yiing; Jansen, Camden; Malladi, Venkat S; Cline, Melissa S; Erickson, Drew T; Kirkup, Vanessa M; Learned, Katrina; Sloan, Cricket A; Rosenbloom, Kate R; Lacerda de Sousa, Beatriz; Beal, Kathryn; Pignatelli, Miguel; Flicek, Paul; Lian, Jin; Kahveci, Tamer; Lee, Dongwon; Kent, W James; Ramalho Santos, Miguel; Herrero, Javier; Notredame, Cedric; Johnson, Audra; Vong, Shinny; Lee, Kristen; Bates, Daniel; Neri, Fidencio; Diegel, Morgan; Canfield, Theresa; Sabo, Peter J; Wilken, Matthew S; Reh, Thomas A; Giste, Erika; Shafer, Anthony; Kutyavin, Tanya; Haugen, Eric; Dunn, Douglas; Reynolds, Alex P; Neph, Shane; Humbert, Richard; Hansen, R Scott; De Bruijn, Marella; Selleri, Licia; Rudensky, Alexander; Josefowicz, Steven; Samstein, Robert; Eichler, Evan E; Orkin, Stuart H; Levasseur, Dana; Papayannopoulou, Thalia; Chang, Kai-Hsin; Skoultchi, Arthur; Gosh, Srikanta; Disteche, Christine; Treuting, Piper; Wang, Yanli; Weiss, Mitchell J; Blobel, Gerd A; Cao, Xiaoyi; Zhong, Sheng; Wang, Ting; Good, Peter J; Lowdon, Rebecca F; Adams, Leslie B; Zhou, Xiao-Qiao; Pazin, Michael J; Feingold, Elise A; Wold, Barbara; Taylor, James; Mortazavi, Ali; Weissman, Sherman M; Stamatoyannopoulos, John A; Snyder, Michael P; Guigo, Roderic; Gingeras, Thomas R; Gilbert, David M; Hardison, Ross C; Beer, Michael A; Ren, Bing

    2014-11-20

    The laboratory mouse shares the majority of its protein-coding genes with humans, making it the premier model organism in biomedical research, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases.

  2. Comparative Genomic Analysis of Holospora spp., Intranuclear Symbionts of Paramecia

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    Sofya K. Garushyants

    2018-04-01

    Full Text Available While most endosymbiotic bacteria are transmitted only vertically, Holospora spp., an alphaproteobacterium from the Rickettsiales order, can desert its host and invade a new one. All bacteria from the genus Holospora are intranuclear symbionts of ciliates Paramecium spp. with strict species and nuclear specificity. Comparative metabolic reconstruction based on the newly sequenced genome of Holospora curviuscula, a macronuclear symbiont of Paramecium bursaria, and known genomes of other Holospora species shows that even though all Holospora spp. can persist outside the host, they cannot synthesize most of the essential small molecules, such as amino acids, and lack some central energy metabolic pathways, including glycolysis and the citric acid cycle. As the main energy source, Holospora spp. likely rely on nucleotides pirated from the host. Holospora-specific genes absent from other Rickettsiales are possibly involved in the lifestyle switch from the infectious to the reproductive form and in cell invasion.

  3. Landscape genomic approach to detect selection signatures in locally adapted Brazilian swine genetic groups.

    Science.gov (United States)

    Cesconeto, Robson Jose; Joost, Stéphane; McManus, Concepta Margaret; Paiva, Samuel Rezende; Cobuci, Jaime Araujo; Braccini, Jose

    2017-11-01

    Samples of 191 animals from 18 different Brazilian locally adapted swine genetic groups were genotyped using Illumina Porcine SNP60 BeadChip in order to identify selection signatures related to the monthly variation of Brazilian environmental variables. Using BayeScan software, 71 SNP markers were identified as F ST outliers and 60 genotypes (58 markers) were found by Samβada software in 371 logistic models correlated with 112 environmental variables. Five markers were identified in both methods, with a Kappa value of 0.073 (95% CI: 0.011-0.134). The frequency of these markers indicated a clear north-south country division that reflects Brazilian environmental differences in temperature, solar radiation, and precipitation. Global spatial territory correlation for environmental variables corroborates this finding (average Moran's I = 0.89, range from 0.55 to 0.97). The distribution of alleles over the territory was not strongly correlated with the breed/genetic groups. These results are congruent with previous mtDNA studies and should be used to direct germplasm collection for the National gene bank.

  4. Complete genome sequence of Enterococcus faecium strain TX16 and comparative genomic analysis of Enterococcus faecium genomes

    Science.gov (United States)

    2012-01-01

    Background Enterococci are among the leading causes of hospital-acquired infections in the United States and Europe, with Enterococcus faecalis and Enterococcus faecium being the two most common species isolated from enterococcal infections. In the last decade, the proportion of enterococcal infections caused by E. faecium has steadily increased compared to other Enterococcus species. Although the underlying mechanism for the gradual replacement of E. faecalis by E. faecium in the hospital environment is not yet understood, many studies using genotyping and phylogenetic analysis have shown the emergence of a globally dispersed polyclonal subcluster of E. faecium strains in clinical environments. Systematic study of the molecular epidemiology and pathogenesis of E. faecium has been hindered by the lack of closed, complete E. faecium genomes that can be used as references. Results In this study, we report the complete genome sequence of the E. faecium strain TX16, also known as DO, which belongs to multilocus sequence type (ST) 18, and was the first E. faecium strain ever sequenced. Whole genome comparison of the TX16 genome with 21 E. faecium draft genomes confirmed that most clinical, outbreak, and hospital-associated (HA) strains (including STs 16, 17, 18, and 78), in addition to strains of non-hospital origin, group in the same clade (referred to as the HA clade) and are evolutionally considerably more closely related to each other by phylogenetic and gene content similarity analyses than to isolates in the community-associated (CA) clade with approximately a 3–4% average nucleotide sequence difference between the two clades at the core genome level. Our study also revealed that many genomic loci in the TX16 genome are unique to the HA clade. 380 ORFs in TX16 are HA-clade specific and antibiotic resistance genes are enriched in HA-clade strains. Mobile elements such as IS16 and transposons were also found almost exclusively in HA strains, as previously reported

  5. Comparative Genomics of the Ubiquitous, Hydrocarbon-degrading Genus Marinobacter

    Science.gov (United States)

    Singer, E.; Webb, E.; Edwards, K. J.

    2012-12-01

    The genus Marinobacter is amongst the most ubiquitous in the global oceans and strains have been isolated from a wide variety of marine environments, including offshore oil-well heads, coastal thermal springs, Antarctic sea water, saline soils and associations with diatoms and dinoflagellates. Many strains have been recognized to be important hydrocarbon degraders in various marine habitats presenting sometimes extreme pH or salinity conditions. Analysis of the genome of M. aquaeolei revealed enormous adaptation versatility with an assortment of strategies for carbon and energy acquisition, sensation, and defense. In an effort to elucidate the ecological and biogeochemical significance of the Marinobacters, seven Marinobacter strains from diverse environments were included in a comparative genomics study. Genomes were screened for metabolic and adaptation potential to elucidate the strategies responsible for the omnipresence of the Marinobacter genus and their remedial action potential in hydrocarbon-polluted waters. The core genome predominantly encodes for key genes involved in hydrocarbon degradation, biofilm-relevant processes, including utilization of external DNA, halotolerance, as well as defense mechanisms against heavy metals, antibiotics, and toxins. All Marinobacter strains were observed to degrade a wide spectrum of hydrocarbon species, including aliphatic, polycyclic aromatic as well as acyclic isoprenoid compounds. Various genes predicted to facilitate hydrocarbon degradation, e.g. alkane 1-monooxygenase, appear to have originated from lateral gene transfer as they are located on gene clusters of 10-20% lower GC-content compared to genome averages and are flanked by transposases. Top ortholog hits are found in other hydrocarbon degrading organisms, e.g. Alcanivorax borkumensis. Strategies for hydrocarbon uptake encoded by various Marinobacter strains include cell surface hydrophobicity adaptation via capsular polysaccharide biosynthesis and attachment

  6. Comparative genomics of Serratia spp.: two paths towards endosymbiotic life.

    Directory of Open Access Journals (Sweden)

    Alejandro Manzano-Marín

    Full Text Available Symbiosis is a widespread phenomenon in nature, in which insects show a great number of these associations. Buchnera aphidicola, the obligate endosymbiont of aphids, coexists in some species with another intracellular bacterium, Serratia symbiotica. Of particular interest is the case of the cedar aphid Cinara cedri, where B. aphidicola BCc and S. symbiotica SCc need each other to fulfil their symbiotic role with the insect. Moreover, various features seem to indicate that S. symbiotica SCc is closer to an obligate endosymbiont than to other facultative S. symbiotica, such as the one described for the aphid Acirthosyphon pisum (S. symbiotica SAp. This work is based on the comparative genomics of five strains of Serratia, three free-living and two endosymbiotic ones (one facultative and one obligate which should allow us to dissect the genome reduction taking place in the adaptive process to an intracellular life-style. Using a pan-genome approach, we have identified shared and strain-specific genes from both endosymbiotic strains and gained insight into the different genetic reduction both S. symbiotica have undergone. We have identified both retained and reduced functional categories in S. symbiotica compared to the Free-Living Serratia (FLS that seem to be related with its endosymbiotic role in their specific host-symbiont systems. By means of a phylogenomic reconstruction we have solved the position of both endosymbionts with confidence, established the probable insect-pathogen origin of the symbiotic clade as well as the high amino-acid substitution rate in S. symbiotica SCc. Finally, we were able to quantify the minimal number of rearrangements suffered in the endosymbiotic lineages and reconstruct a minimal rearrangement phylogeny. All these findings provide important evidence for the existence of at least two distinctive S. symbiotica lineages that are characterized by different rearrangements, gene content, genome size and branch lengths.

  7. Comparative Genomics of Smut Pathogens: Insights From Orphans and Positively Selected Genes Into Host Specialization

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    Juliana Benevenuto

    2018-04-01

    Full Text Available Host specialization is a key evolutionary process for the diversification and emergence of new pathogens. However, the molecular determinants of host range are poorly understood. Smut fungi are biotrophic pathogens that have distinct and narrow host ranges based on largely unknown genetic determinants. Hence, we aimed to expand comparative genomics analyses of smut fungi by including more species infecting different hosts and to define orphans and positively selected genes to gain further insights into the genetics basis of host specialization. We analyzed nine lineages of smut fungi isolated from eight crop and non-crop hosts: maize, barley, sugarcane, wheat, oats, Zizania latifolia (Manchurian rice, Echinochloa colona (a wild grass, and Persicaria sp. (a wild dicot plant. We assembled two new genomes: Ustilago hordei (strain Uhor01 isolated from oats and U. tritici (strain CBS 119.19 isolated from wheat. The smut genomes were of small sizes, ranging from 18.38 to 24.63 Mb. U. hordei species experienced genome expansions due to the proliferation of transposable elements and the amount of these elements varied among the two strains. Phylogenetic analysis confirmed that Ustilago is not a monophyletic genus and, furthermore, detected misclassification of the U. tritici specimen. The comparison between smut pathogens of crop and non-crop hosts did not reveal distinct signatures, suggesting that host domestication did not play a dominant role in shaping the evolution of smuts. We found that host specialization in smut fungi likely has a complex genetic basis: different functional categories were enriched in orphans and lineage-specific selected genes. The diversification and gain/loss of effector genes are probably the most important determinants of host specificity.

  8. Signatures of Selection in the Genomes of Commercial and Non-Commercial Chicken Breeds

    Science.gov (United States)

    Elferink, Martin G.; Megens, Hendrik-Jan; Vereijken, Addie; Hu, Xiaoxiang; Crooijmans, Richard P. M. A.; Groenen, Martien A. M.

    2012-01-01

    Identifying genomics regions that are affected by selection is important to understand the domestication and selection history of the domesticated chicken, as well as understanding molecular pathways underlying phenotypic traits and breeding goals. While whole-genome approaches, either high-density SNP chips or massively parallel sequencing, have been successfully applied to identify evidence for selective sweeps in chicken, it has been difficult to distinguish patterns of selection and stochastic and breed specific effects. Here we present a study to identify selective sweeps in a large number of chicken breeds (67 in total) using a high-density (58 K) SNP chip. We analyzed commercial chickens representing all major breeding goals. In addition, we analyzed non-commercial chicken diversity for almost all recognized traditional Dutch breeds and a selection of representative breeds from China. Based on their shared history or breeding goal we in silico grouped the breeds into 14 breed groups. We identified 396 chromosomal regions that show suggestive evidence of selection in at least one breed group with 26 of these regions showing strong evidence of selection. Of these 26 regions, 13 were previously described and 13 yield new candidate genes for performance traits in chicken. Our approach demonstrates the strength of including many different populations with similar, and breed groups with different selection histories to reduce stochastic effects based on single populations. PMID:22384281

  9. A comparative evaluation of genome assembly reconciliation tools.

    Science.gov (United States)

    Alhakami, Hind; Mirebrahim, Hamid; Lonardi, Stefano

    2017-05-18

    The majority of eukaryotic genomes are unfinished due to the algorithmic challenges of assembling them. A variety of assembly and scaffolding tools are available, but it is not always obvious which tool or parameters to use for a specific genome size and complexity. It is, therefore, common practice to produce multiple assemblies using different assemblers and parameters, then select the best one for public release. A more compelling approach would allow one to merge multiple assemblies with the intent of producing a higher quality consensus assembly, which is the objective of assembly reconciliation. Several assembly reconciliation tools have been proposed in the literature, but their strengths and weaknesses have never been compared on a common dataset. We fill this need with this work, in which we report on an extensive comparative evaluation of several tools. Specifically, we evaluate contiguity, correctness, coverage, and the duplication ratio of the merged assembly compared to the individual assemblies provided as input. None of the tools we tested consistently improved the quality of the input GAGE and synthetic assemblies. Our experiments show an increase in contiguity in the consensus assembly when the original assemblies already have high quality. In terms of correctness, the quality of the results depends on the specific tool, as well as on the quality and the ranking of the input assemblies. In general, the number of misassemblies ranges from being comparable to the best of the input assembly to being comparable to the worst of the input assembly.

  10. Comparative Genomics of Flatworms (Platyhelminthes) Reveals Shared Genomic Features of Ecto- and Endoparastic Neodermata

    Science.gov (United States)

    Hahn, Christoph; Fromm, Bastian; Bachmann, Lutz

    2014-01-01

    The ectoparasitic Monogenea comprise a major part of the obligate parasitic flatworm diversity. Although genomic adaptations to parasitism have been studied in the endoparasitic tapeworms (Cestoda) and flukes (Trematoda), no representative of the Monogenea has been investigated yet. We present the high-quality draft genome of Gyrodactylus salaris, an economically important monogenean ectoparasite of wild Atlantic salmon (Salmo salar). A total of 15,488 gene models were identified, of which 7,102 were functionally annotated. The controversial phylogenetic relationships within the obligate parasitic Neodermata were resolved in a phylogenomic analysis using 1,719 gene models (alignment length of >500,000 amino acids) for a set of 16 metazoan taxa. The Monogenea were found basal to the Cestoda and Trematoda, which implies ectoparasitism being plesiomorphic within the Neodermata and strongly supports a common origin of complex life cycles. Comparative analysis of seven parasitic flatworm genomes identified shared genomic features for the ecto- and endoparasitic lineages, such as a substantial reduction of the core bilaterian gene complement, including the homeodomain-containing genes, and a loss of the piwi and vasa genes, which are considered essential for animal development. Furthermore, the shared loss of functional fatty acid biosynthesis pathways and the absence of peroxisomes, the latter organelles presumed ubiquitous in eukaryotes except for parasitic protozoans, were inferred. The draft genome of G. salaris opens for future in-depth analyses of pathogenicity and host specificity of poorly characterized G. salaris strains, and will enhance studies addressing the genomics of host–parasite interactions and speciation in the highly diverse monogenean flatworms. PMID:24732282

  11. The complete genome sequence and comparative genome analysis of the high pathogenicity Yersinia enterocolitica strain 8081.

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    Nicholas R Thomson

    2006-12-01

    Full Text Available The human enteropathogen, Yersinia enterocolitica, is a significant link in the range of Yersinia pathologies extending from mild gastroenteritis to bubonic plague. Comparison at the genomic level is a key step in our understanding of the genetic basis for this pathogenicity spectrum. Here we report the genome of Y. enterocolitica strain 8081 (serotype 0:8; biotype 1B and extensive microarray data relating to the genetic diversity of the Y. enterocolitica species. Our analysis reveals that the genome of Y. enterocolitica strain 8081 is a patchwork of horizontally acquired genetic loci, including a plasticity zone of 199 kb containing an extraordinarily high density of virulence genes. Microarray analysis has provided insights into species-specific Y. enterocolitica gene functions and the intraspecies differences between the high, low, and nonpathogenic Y. enterocolitica biotypes. Through comparative genome sequence analysis we provide new information on the evolution of the Yersinia. We identify numerous loci that represent ancestral clusters of genes potentially important in enteric survival and pathogenesis, which have been lost or are in the process of being lost, in the other sequenced Yersinia lineages. Our analysis also highlights large metabolic operons in Y. enterocolitica that are absent in the related enteropathogen, Yersinia pseudotuberculosis, indicating major differences in niche and nutrients used within the mammalian gut. These include clusters directing, the production of hydrogenases, tetrathionate respiration, cobalamin synthesis, and propanediol utilisation. Along with ancestral gene clusters, the genome of Y. enterocolitica has revealed species-specific and enteropathogen-specific loci. This has provided important insights into the pathology of this bacterium and, more broadly, into the evolution of the genus. Moreover, wider investigations looking at the patterns of gene loss and gain in the Yersinia have highlighted common

  12. A model of the statistical power of comparative genome sequence analysis.

    OpenAIRE

    Sean R Eddy

    2005-01-01

    Comparative genome sequence analysis is powerful, but sequencing genomes is expensive. It is desirable to be able to predict how many genomes are needed for comparative genomics, and at what evolutionary distances. Here I describe a simple mathematical model for the common problem of identifying conserved sequences. The model leads to some useful rules of thumb. For a given evolutionary distance, the number of comparative genomes needed for a constant level of statistical stringency in identi...

  13. The use of MPSS for whole-genome transcriptional analysis in Arabidopsis.

    Science.gov (United States)

    Meyers, Blake C; Tej, Shivakundan Singh; Vu, Tam H; Haudenschild, Christian D; Agrawal, Vikas; Edberg, Steve B; Ghazal, Hassan; Decola, Shannon

    2004-08-01

    We have generated 36,991,173 17-base sequence "signatures" representing transcripts from the model plant Arabidopsis. These data were derived by massively parallel signature sequencing (MPSS) from 14 libraries and comprised 268,132 distinct sequences. Comparable data were also obtained with 20-base signatures. We developed a method for handling these data and for comparing these signatures to the annotated Arabidopsis genome. As part of this procedure, 858,019 potential or "genomic" signatures were extracted from the Arabidopsis genome and classified based on the position and orientation of the signatures relative to annotated genes. A comparison of genomic and expressed signatures matched 67,735 signatures predicted to be derived from distinct transcripts and expressed at significant levels. Expressed signatures were derived from the sense strand of at least 19,088 of 29,084 annotated genes. A comparison of the genomic and expression signatures demonstrated that approximately 7.7% of genomic signatures were underrepresented in the expression data. These genomic signatures contained one of 20 four-base words that were consistently associated with reduced MPSS abundances. More than 89% of the sum of the expressed signature abundances matched the Arabidopsis genome, and many of the unmatched signatures found in high abundances were predicted to match to previously uncharacterized transcripts. Copyright 2004 Cold Spring Harbor Laboratory Press ISSN

  14. Complete chloroplast genome sequence of Elodea canadensis and comparative analyses with other monocot plastid genomes.

    Science.gov (United States)

    Huotari, Tea; Korpelainen, Helena

    2012-10-15

    Elodea canadensis is an aquatic angiosperm native to North America. It has attracted great attention due to its invasive nature when transported to new areas in its non-native range. We have determined the complete nucleotide sequence of the chloroplast (cp) genome of Elodea. Taxonomically Elodea is a basal monocot, and only few monocot cp genomes representing early lineages of monocots have been sequenced so far. The genome is a circular double-stranded DNA molecule 156,700 bp in length, and has a typical structure with large (LSC 86,194 bp) and small (SSC 17,810 bp) single-copy regions separated by a pair of inverted repeats (IRs 26,348 bp each). The Elodea cp genome contains 113 unique genes and 16 duplicated genes in the IR regions. A comparative analysis showed that the gene order and organization of the Elodea cp genome is almost identical to that of Amborella trichopoda, a basal angiosperm. The structure of IRs in Elodea is unique among monocot species with the whole cp genome sequenced. In Elodea and another monocot Lemna minor the borders between IRs and LSC are located upstream of rps 19 gene and downstream of trnH-GUG gene, while in most monocots, IR has extended to include both trnH and rps 19 genes. A phylogenetic analysis conducted using Bayesian method, based on the DNA sequences of 81 chloroplast genes from 17 monocot taxa provided support for the placement of Elodea together with Lemna as a basal monocot and the next diverging lineage of monocots after Acorales. In comparison with other monocots, the Elodea cp genome has gone through only few rearrangements or gene losses. IR of Elodea has a unique structure among the monocot species studied so far as its structure is similar to that of a basal angiosperm Amborella. This result together with phylogenetic analyses supports the placement of Elodea as a basal monocot to the next diverging lineage of monocots after Acorales. So far, only few cp genomes representing early lineages of monocots have been

  15. Medaka: a promising model animal for comparative population genomics

    Directory of Open Access Journals (Sweden)

    Watanabe Koji

    2009-05-01

    Full Text Available Abstract Background Within-species genome diversity has been best studied in humans. The international HapMap project has revealed a tremendous amount of single-nucleotide polymorphisms (SNPs among humans, many of which show signals of positive selection during human evolution. In most of the cases, however, functional differences between the alleles remain experimentally unverified due to the inherent difficulty of human genetic studies. It would therefore be highly useful to have a vertebrate model with the following characteristics: (1 high within-species genetic diversity, (2 a variety of gene-manipulation protocols already developed, and (3 a completely sequenced genome. Medaka (Oryzias latipes and its congeneric species, tiny fresh-water teleosts distributed broadly in East and Southeast Asia, meet these criteria. Findings Using Oryzias species from 27 local populations, we conducted a simple screening of nonsynonymous SNPs for 11 genes with apparent orthology between medaka and humans. We found medaka SNPs for which the same sites in human orthologs are known to be highly differentiated among the HapMap populations. Importantly, some of these SNPs show signals of positive selection. Conclusion These results indicate that medaka is a promising model system for comparative population genomics exploring the functional and adaptive significance of allelic differentiations.

  16. Comparative Genomic Analysis of Mannheimia haemolytica from Bovine Sources.

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    Cassidy L Klima

    Full Text Available Bovine respiratory disease is a common health problem in beef production. The primary bacterial agent involved, Mannheimia haemolytica, is a target for antimicrobial therapy and at risk for associated antimicrobial resistance development. The role of M. haemolytica in pathogenesis is linked to serotype with serotypes 1 (S1 and 6 (S6 isolated from pneumonic lesions and serotype 2 (S2 found in the upper respiratory tract of healthy animals. Here, we sequenced the genomes of 11 strains of M. haemolytica, representing all three serotypes and performed comparative genomics analysis to identify genetic features that may contribute to pathogenesis. Possible virulence associated genes were identified within 14 distinct prophage, including a periplasmic chaperone, a lipoprotein, peptidoglycan glycosyltransferase and a stress response protein. Prophage content ranged from 2-8 per genome, but was higher in S1 and S6 strains. A type I-C CRISPR-Cas system was identified in each strain with spacer diversity and organization conserved among serotypes. The majority of spacers occur in S1 and S6 strains and originate from phage suggesting that serotypes 1 and 6 may be more resistant to phage predation. However, two spacers complementary to the host chromosome targeting a UDP-N-acetylglucosamine 2-epimerase and a glycosyl transferases group 1 gene are present in S1 and S6 strains only indicating these serotypes may employ CRISPR-Cas to regulate gene expression to avoid host immune responses or enhance adhesion during infection. Integrative conjugative elements are present in nine of the eleven genomes. Three of these harbor extensive multi-drug resistance cassettes encoding resistance against the majority of drugs used to combat infection in beef cattle, including macrolides and tetracyclines used in human medicine. The findings here identify key features that are likely contributing to serotype related pathogenesis and specific targets for vaccine design

  17. Reconstructing the Evolution of Brachypodium Genomes Using Comparative Chromosome Painting.

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    Alexander Betekhtin

    Full Text Available Brachypodium distachyon is a model for the temperate cereals and grasses and has a biology, genomics infrastructure and cytogenetic platform fit for purpose. It is a member of a genus with fewer than 20 species, which have different genome sizes, basic chromosome numbers and ploidy levels. The phylogeny and interspecific relationships of this group have not to date been resolved by sequence comparisons and karyotypical studies. The aims of this study are not only to reconstruct the evolution of Brachypodium karyotypes to resolve the phylogeny, but also to highlight the mechanisms that shape the evolution of grass genomes. This was achieved through the use of comparative chromosome painting (CCP which hybridises fluorescent, chromosome-specific probes derived from B. distachyon to homoeologous meiotic chromosomes of its close relatives. The study included five diploids (B. distachyon 2n = 10, B. sylvaticum 2n = 18, B. pinnatum 2n = 16; 2n = 18, B. arbuscula 2n = 18 and B. stacei 2n = 20 three allotetraploids (B. pinnatum 2n = 28, B. phoenicoides 2n = 28 and B. hybridum 2n = 30, and two species of unknown ploidy (B. retusum 2n = 38 and B. mexicanum 2n = 40. On the basis of the patterns of hybridisation and incorporating published data, we propose two alternative, but similar, models of karyotype evolution in the genus Brachypodium. According to the first model, the extant genome of B. distachyon derives from B. mexicanum or B. stacei by several rounds of descending dysploidy, and the other diploids evolve from B. distachyon via ascending dysploidy. The allotetraploids arise by interspecific hybridisation and chromosome doubling between B. distachyon and other diploids. The second model differs from the first insofar as it incorporates an intermediate 2n = 18 species between the B. mexicanum or B. stacei progenitors and the dysploidic B. distachyon.

  18. Comparative genomics of Mycoplasma: analysis of conserved essential genes and diversity of the pan-genome.

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    Wei Liu

    Full Text Available Mycoplasma, the smallest self-replicating organism with a minimal metabolism and little genomic redundancy, is expected to be a close approximation to the minimal set of genes needed to sustain bacterial life. This study employs comparative evolutionary analysis of twenty Mycoplasma genomes to gain an improved understanding of essential genes. By analyzing the core genome of mycoplasmas, we finally revealed the conserved essential genes set for mycoplasma survival. Further analysis showed that the core genome set has many characteristics in common with experimentally identified essential genes. Several key genes, which are related to DNA replication and repair and can be disrupted in transposon mutagenesis studies, may be critical for bacteria survival especially over long period natural selection. Phylogenomic reconstructions based on 3,355 homologous groups allowed robust estimation of phylogenetic relatedness among mycoplasma strains. To obtain deeper insight into the relative roles of molecular evolution in pathogen adaptation to their hosts, we also analyzed the positive selection pressures on particular sites and lineages. There appears to be an approximate correlation between the divergence of species and the level of positive selection detected in corresponding lineages.

  19. Whole genome comparative analysis of four Georgian grape cultivars.

    Science.gov (United States)

    Tabidze, V; Pipia, I; Gogniashvili, M; Kunelauri, N; Ujmajuridze, L; Pirtskhalava, M; Vishnepolsky, B; Hernandez, A G; Fields, C J; Beridze, Tengiz

    2017-12-01

    Grapevine is the one of the most important fruit species in the world. Comparative genome sequencing of grape cultivars is very important for the interpretation of the grape genome and understanding its evolution. The genomes of four Georgian grape cultivars-Chkhaveri, Saperavi, Meskhetian green, and Rkatsiteli, belonging to different haplogroups, were resequenced. The shotgun genomic libraries of grape cultivars were sequenced on an Illumina HiSeq. Pinot Noir nuclear, mitochondrial, and chloroplast DNA were used as reference. Mitochondrial DNA of Chkhaveri closely matches that of the reference Pinot noir mitochondrial DNA, with the exception of 16 SNPs found in the Chkhaveri mitochondrial DNA. The number of SNPs in mitochondrial DNA from Saperavi, Meskhetian green, and Rkatsiteli was 764, 702, and 822, respectively. Nuclear DNA differs from the reference by 1,800,675 nt in Chkhaveri, 1,063,063 nt in Meskhetian green, 2,174,995 in Saperavi, and 5,011,513 in Rkatsiteli. Unlike mtDNA Pinot noir, chromosomal DNA is closer to the Meskhetian green than to other cultivars. Substantial differences in the number of SNPs in mitochondrial and nuclear DNA of Chkhaveri and Pinot noir cultivars are explained by backcrossing or introgression of their wild predecessors before or during the process of domestication. Annotation of chromosomal DNA of Georgian grape cultivars by MEGANTE, a web-based annotation system, shows 66,745 predicted genes (Chkhaveri-17,409; Saperavi-17,021; Meskhetian green-18,355; and Rkatsiteli-13,960). Among them, 106 predicted genes and 43 pseudogenes of terpene synthase genes were found in chromosomes 12, 18 random (18R), and 19. Four novel TPS genes not present in reference Pinot noir DNA were detected. Two of them-germacrene A synthase (Chromosome 18R) and (-) germacrene D synthase (Chromosome 19) can be identified as putatively full-length proteins. This work performs the first attempt of the comparative whole genome analysis of different haplogroups

  20. Genomic signatures of local directional selection in a high gene flow marine organism; the Atlantic cod (Gadus morhua

    Directory of Open Access Journals (Sweden)

    Mittelholzer Christian

    2009-12-01

    Full Text Available Abstract Background Marine fishes have been shown to display low levels of genetic structuring and associated high levels of gene flow, suggesting shallow evolutionary trajectories and, possibly, limited or lacking adaptive divergence among local populations. We investigated variation in 98 gene-associated single nucleotide polymorphisms (SNPs for evidence of selection in local populations of Atlantic cod (Gadus morhua L. across the species distribution. Results Our global genome scan analysis identified eight outlier gene loci with very high statistical support, likely to be subject to directional selection in local demes, or closely linked to loci under selection. Likewise, on a regional south/north transect of central and eastern Atlantic populations, seven loci displayed strongly elevated levels of genetic differentiation. Selection patterns among populations appeared to be relatively widespread and complex, i.e. outlier loci were generally not only associated with one of a few divergent local populations. Even on a limited geographical scale between the proximate North Sea and Baltic Sea populations four loci displayed evidence of adaptive evolution. Temporal genome scan analysis applied to DNA from archived otoliths from a Faeroese population demonstrated stability of the intra-population variation over 24 years. An exploratory landscape genetic analysis was used to elucidate potential effects of the most likely environmental factors responsible for the signatures of local adaptation. We found that genetic variation at several of the outlier loci was better correlated with temperature and/or salinity conditions at spawning grounds at spawning time than with geographic distance per se. Conclusion These findings illustrate that adaptive population divergence may indeed be prevalent despite seemingly high levels of gene flow, as found in most marine fishes. Thus, results have important implications for our understanding of the interplay of

  1. Comparative Genomics of Escherichia coli Strains Causing Urinary Tract Infections

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk; Hancock, Viktoria; Schembri, Mark A.

    2011-01-01

    The virulence determinants of uropathogenic Escherichia coli have been studied extensively over the years, but relatively little is known about what differentiates isolates causing various types of urinary tract infections. In this study, we compared the genomic profiles of 45 strains from a range...... and their disease categories but strong correlation between the genotype and the phylogenetic group association. Also, very few genetic differences may exist between isolates causing symptomatic and asymptomatic infections. Only relatively few genes that could potentially differentiate between the individual...

  2. Genomic signatures of paleodrainages in a freshwater fish along the southeastern coast of Brazil: genetic structure reflects past riverine properties.

    Science.gov (United States)

    Thomaz, A T; Malabarba, L R; Knowles, L L

    2017-10-01

    Past shifts in connectivity in riverine environments (for example, sea-level changes) and the properties of current drainages can act as drivers of genetic structure and demographic processes in riverine population of fishes. However, it is unclear whether the same river properties that structure variation on recent timescales will also leave similar genomic signatures that reflect paleodrainage properties. By characterizing genetic structure in a freshwater fish species (Hollandichthys multifasciatus) from a system of basins along the Atlantic coast of Brazil we test for the effects of paleodrainages caused by sea-level changes during the Pleistocene. Given that the paleodrainage properties differ along the Brazilian coast, we also evaluate whether estimated genetic diversity within paleodrainages can be explained by past riverine properties (i.e., area and number of rivers in a paleodrainage). Our results demonstrate that genetic structure between populations is not just highly concordant with paleodrainages, but that differences in the genetic diversity among paleodrainages correspond to the joint effect of differences in the area encompassed by, and the number of rivers, within a paleodrainage. Our findings extend the influence of current riverine properties on genetic diversity to those associated with past paleodrainage properties. We discuss how these findings may explain the inconsistent support for paleodrainages in structuring divergence from different global regions and the importance of taking into account past conditions for understanding the high species diversity of freshwater fish that we currently observe in the world, and especially in the Neotropics.

  3. Comparative analysis of genomic signal processing for microarray data clustering.

    Science.gov (United States)

    Istepanian, Robert S H; Sungoor, Ala; Nebel, Jean-Christophe

    2011-12-01

    Genomic signal processing is a new area of research that combines advanced digital signal processing methodologies for enhanced genetic data analysis. It has many promising applications in bioinformatics and next generation of healthcare systems, in particular, in the field of microarray data clustering. In this paper we present a comparative performance analysis of enhanced digital spectral analysis methods for robust clustering of gene expression across multiple microarray data samples. Three digital signal processing methods: linear predictive coding, wavelet decomposition, and fractal dimension are studied to provide a comparative evaluation of the clustering performance of these methods on several microarray datasets. The results of this study show that the fractal approach provides the best clustering accuracy compared to other digital signal processing and well known statistical methods.

  4. Genomic signatures of adaptive introgression from European mouflon into domestic sheep.

    Science.gov (United States)

    Barbato, Mario; Hailer, Frank; Orozco-terWengel, Pablo; Kijas, James; Mereu, Paolo; Cabras, Pierangela; Mazza, Raffaele; Pirastru, Monica; Bruford, Michael W

    2017-08-08

    Mouflon (Ovis aries musimon) became extinct from mainland Europe after the Neolithic, but remnant populations from the Mediterranean islands of Corsica and Sardinia have been used for reintroductions across Europe since the 19 th -century. Mouflon x sheep hybrids are larger-bodied than mouflon, potentially showing increased male reproductive success, but little is known about genomic levels of admixture, or about the adaptive significance of introgression between resident mouflon and local sheep breeds. Here we analysed Ovine medium-density SNP array genotypes of 92 mouflon from six geographic regions, along with data from 330 individuals of 16 domestic sheep breeds. We found lower levels of genetic diversity in mouflon than in domestic sheep, consistent with past bottlenecks in mouflon. Introgression signals were bidirectional and affected most mouflon and sheep populations, being strongest in one Sardinian mouflon population. Developing and using a novel approach to identify chromosomal regions with consistent introgression signals, we infer adaptive introgression from mouflon to domestic sheep related to immunity mechanisms, but not in the opposite direction. Further, we infer that Soay and Sarda sheep carry introgressed mouflon alleles involved in bitter taste perception and/or innate immunity. Our results illustrate the potential for adaptive introgression even among recently diverged populations.

  5. Comparative genomic characterization of citrus-associated Xylella fastidiosa strains

    Directory of Open Access Journals (Sweden)

    Nunes Luiz R

    2007-12-01

    Full Text Available Abstract Background The xylem-inhabiting bacterium Xylella fastidiosa (Xf is the causal agent of Pierce's disease (PD in vineyards and citrus variegated chlorosis (CVC in orange trees. Both of these economically-devastating diseases are caused by distinct strains of this complex group of microorganisms, which has motivated researchers to conduct extensive genomic sequencing projects with Xf strains. This sequence information, along with other molecular tools, have been used to estimate the evolutionary history of the group and provide clues to understand the capacity of Xf to infect different hosts, causing a variety of symptoms. Nonetheless, although significant amounts of information have been generated from Xf strains, a large proportion of these efforts has concentrated on the study of North American strains, limiting our understanding about the genomic composition of South American strains – which is particularly important for CVC-associated strains. Results This paper describes the first genome-wide comparison among South American Xf strains, involving 6 distinct citrus-associated bacteria. Comparative analyses performed through a microarray-based approach allowed identification and characterization of large mobile genetic elements that seem to be exclusive to South American strains. Moreover, a large-scale sequencing effort, based on Suppressive Subtraction Hybridization (SSH, identified 290 new ORFs, distributed in 135 Groups of Orthologous Elements, throughout the genomes of these bacteria. Conclusion Results from microarray-based comparisons provide further evidence concerning activity of horizontally transferred elements, reinforcing their importance as major mediators in the evolution of Xf. Moreover, the microarray-based genomic profiles showed similarity between Xf strains 9a5c and Fb7, which is unexpected, given the geographical and chronological differences associated with the isolation of these microorganisms. The newly

  6. Comparative Genomics and Transcriptomic Analysis of Mycobacterium Kansasii

    KAUST Repository

    Alzahid, Yara

    2014-04-01

    The group of Mycobacteria is one of the most intensively studied bacterial taxa, as they cause the two historical and worldwide known diseases: leprosy and tuberculosis. Mycobacteria not identified as tuberculosis or leprosy complex, have been referred to by ‘environmental mycobacteria’ or ‘Nontuberculous mycobacteria (NTM). Mycobacterium kansasii (M. kansasii) is one of the most frequent NTM pathogens, as it causes pulmonary disease in immuno-competent patients and pulmonary, and disseminated disease in patients with various immuno-deficiencies. There have been five documented subtypes of this bacterium, by different molecular typing methods, showing that type I causes tuberculosis-like disease in healthy individuals, and type II in immune-compromised individuals. The remaining types are said to be environmental, thereby, not causing any diseases. The aim of this project was to conduct a comparative genomic study of M. kansasii types I-V and investigating the gene expression level of those types. From various comparative genomics analysis, provided genomics evidence on why M. kansasii type I is considered pathogenic, by focusing on three key elements that are involved in virulence of Mycobacteria: ESX secretion system, Phospholipase c (plcb) and Mammalian cell entry (Mce) operons. The results showed the lack of the espA operon in types II-V, which renders the ESX- 1 operon dysfunctional, as espA is one of the key factors that control this secretion system. However, gene expression analysis showed this operon to be deleted in types II, III and IV. Furthermore, plcB was found to be truncated in types III and IV. Analysis of Mce operons (1-4) show that mce-1 operon is duplicated, mce-2 is absent and mce-3 and mce-4 is present in one copy in M. kansasii types I-V. Gene expression profiles of type I-IV, showed that the secreted proteins of ESX-1 were slightly upregulated in types II-IV when compared to type I and the secreted forms of ESX-5 were highly down

  7. Genomic signatures for paclitaxel and gemcitabine resistance in breast cancer derived by machine learning.

    Science.gov (United States)

    Dorman, Stephanie N; Baranova, Katherina; Knoll, Joan H M; Urquhart, Brad L; Mariani, Gabriella; Carcangiu, Maria Luisa; Rogan, Peter K

    2016-01-01

    Increasingly, the effectiveness of adjuvant chemotherapy agents for breast cancer has been related to changes in the genomic profile of tumors. We investigated correspondence between growth inhibitory concentrations of paclitaxel and gemcitabine (GI50) and gene copy number, mutation, and expression first in breast cancer cell lines and then in patients. Genes encoding direct targets of these drugs, metabolizing enzymes, transporters, and those previously associated with chemoresistance to paclitaxel (n = 31 genes) or gemcitabine (n = 18) were analyzed. A multi-factorial, principal component analysis (MFA) indicated expression was the strongest indicator of sensitivity for paclitaxel, and copy number and expression were informative for gemcitabine. The factors were combined using support vector machines (SVM). Expression of 15 genes (ABCC10, BCL2, BCL2L1, BIRC5, BMF, FGF2, FN1, MAP4, MAPT, NFKB2, SLCO1B3, TLR6, TMEM243, TWIST1, and CSAG2) predicted cell line sensitivity to paclitaxel with 82% accuracy. Copy number profiles of 3 genes (ABCC10, NT5C, TYMS) together with expression of 7 genes (ABCB1, ABCC10, CMPK1, DCTD, NME1, RRM1, RRM2B), predicted gemcitabine response with 85% accuracy. Expression and copy number studies of two independent sets of patients with known responses were then analyzed with these models. These included tumor blocks from 21 patients that were treated with both paclitaxel and gemcitabine, and 319 patients on paclitaxel and anthracycline therapy. A new paclitaxel SVM was derived from an 11-gene subset since data for 4 of the original genes was unavailable. The accuracy of this SVM was similar in cell lines and tumor blocks (70-71%). The gemcitabine SVM exhibited 62% prediction accuracy for the tumor blocks due to the presence of samples with poor nucleic acid integrity. Nevertheless, the paclitaxel SVM predicted sensitivity in 84% of patients with no or minimal residual disease. Copyright © 2015 Federation of European Biochemical Societies

  8. A Novel Genomic Signature with Translational Significance for Human Idiopathic Pulmonary Fibrosis

    Science.gov (United States)

    Tedrow, John; de Bernard, Simon; Birker-Robaczewska, Magdalena; Gibson, Kevin F.; Guardela, Brenda Juan; Hess, Patrick; Klenk, Axel; Lindell, Kathleen O.; Poirey, Sylvie; Renault, Bérengère; Rey, Markus; Weber, Edgar; Nayler, Oliver; Kaminski, Naftali

    2015-01-01

    The bleomycin-induced rodent lung fibrosis model is commonly used to study mechanisms of lung fibrosis and to test potential therapeutic interventions, despite the well recognized dissimilarities to human idiopathic pulmonary fibrosis (IPF). Therefore, in this study, we sought to identify genomic commonalities between the gene expression profiles from 100 IPF lungs and 108 control lungs that were obtained from the Lung Tissue Research Consortium, and rat lungs harvested at Days 3, 7, 14, 21, 28, 42, and 56 after bleomycin instillation. Surprisingly, the highest gene expression similarity between bleomycin-treated rat and IPF lungs was observed at Day 7. At this point of maximal rat–human commonality, we identified a novel set of 12 disease-relevant translational gene markers (C6, CTHRC1, CTSE, FHL2, GAL, GREM1, LCN2, MMP7, NELL1, PCSK1, PLA2G2A, and SLC2A5) that was able to separate almost all patients with IPF from control subjects in our cohort and in two additional IPF/control cohorts (GSE10667 and GSE24206). Furthermore, in combination with diffusing capacity of carbon monoxide measurements, four members of the translational gene marker set contributed to stratify patients with IPF according to disease severity. Significantly, pirfenidone attenuated the expression change of one (CTHRC1) translational gene marker in the bleomycin-induced lung fibrosis model, in transforming growth factor-β1–treated primary human lung fibroblasts and transforming growth factor-β1–treated human epithelial A549 cells. Our results suggest that a strategy focused on rodent model–human disease commonalities may identify genes that could be used to predict the pharmacological impact of therapeutic interventions, and thus facilitate the development of novel treatments for this devastating lung disease. PMID:25029475

  9. Integrative genome-wide chromatin signature analysis using finite mixture models.

    Science.gov (United States)

    Taslim, Cenny; Lin, Shili; Huang, Kun; Huang, Tim Hui-Ming

    2012-01-01

    Regulation of gene expression has been shown to involve not only the binding of transcription factor at target gene promoters but also the characterization of histone around which DNA is wrapped around. Some histone modification, for example di-methylated histone H3 at lysine 4 (H3K4me2), has been shown to bind to promoters and activate target genes. However, no clear pattern has been shown to predict human promoters. This paper proposed a novel quantitative approach to characterize patterns of promoter regions and predict novel and alternative promoters. We utilized high-throughput data generated using chromatin immunoprecipitation methods followed by massively parallel sequencing (ChIP-seq) technology on RNA Polymerase II (Pol-II) and H3K4me2. Common patterns of promoter regions are modeled using a mixture model involving double-exponential and uniform distributions. The fitted model obtained were then used to search for regions displaying similar patterns over the entire genome to find novel and alternative promoters. Regions with high correlations with the common patterns are identified as putative novel promoters. We used this proposed algorithm, RNA-seq data and several transcripts databases to find alternative promoters in MCF7 (normal breast cancer) cell line. We found 7,235 high-confidence regions that display the identified promoter patterns. Of these, 4,167 regions (58%) can be mapped to RefSeq regions. 2,444 regions are in a gene body or overlap with transcripts (non-coding RNAs, ESTs, and transcripts that are predicted by RNA-seq data). Some of these maybe potential alternative promoters. We also found 193 regions that map to enhancer regions (represented by androgen and estrogen receptor binding sites) and other regulatory regions such as CTCF (CCCTC binding factor) and CpG island. Around 5% (431 regions) of these correlated regions do not overlap with any transcripts or regulatory regions suggesting that these might be potential new promoters or

  10. CGAP: a new comprehensive platform for the comparative analysis of chloroplast genomes.

    Science.gov (United States)

    Cheng, Jinkui; Zeng, Xu; Ren, Guomin; Liu, Zhihua

    2013-03-14

    Chloroplast is an essential organelle in plants which contains independent genome. Chloroplast genomes have been widely used for plant phylogenetic inference recently. The number of complete chloroplast genomes increases rapidly with the development of various genome sequencing projects. However, no comprehensive platform or tool has been developed for the comparative and phylogenetic analysis of chloroplast genomes. Thus, we constructed a comprehensive platform for the comparative and phylogenetic analysis of complete chloroplast genomes which was named as chloroplast genome analysis platform (CGAP). CGAP is an interactive web-based platform which was designed for the comparative analysis of complete chloroplast genomes. CGAP integrated genome collection, visualization, content comparison, phylogeny analysis and annotation functions together. CGAP implemented four web servers including creating complete and regional genome maps of high quality, comparing genome features, constructing phylogenetic trees using complete genome sequences, and annotating draft chloroplast genomes submitted by users. Both CGAP and source code are available at http://www.herbbol.org:8000/chloroplast. CGAP will facilitate the collection, visualization, comparison and annotation of complete chloroplast genomes. Users can customize the comparative and phylogenetic analysis using their own unpublished chloroplast genomes.

  11. Comparative genomic identification and validation of β-defensin genes in the Ovis aries genome.

    Science.gov (United States)

    Hall, T J; McQuillan, C; Finlay, E K; O'Farrelly, C; Fair, S; Meade, K G

    2017-04-04

    β-defensins are small, cationic, antimicrobial peptides found in species across the plant and animal kingdoms. In addition to microbiocidal activity, roles in immunity as well as reproduction have more recently been documented. β-defensin genes in Ovis aries (domestic sheep) have been poorly annotated, having been identified only by automatic gene prediction algorithms. The objective of this study was to use a comparative genomics approach to identify and characterise the β-defensin gene repertoire in sheep using the bovine genome as the primary reference. All 57 currently predicted bovine β-defensin genes were used to find orthologous sequences in the most recent version of the sheep genome (OAR v4.0). Forty three genes were found to have close genomic matches (>70% similarity) between sheep and cattle. The orthologous genes were located in four clusters across the genome, with 4 genes on chromosome 2, 19 genes on chromosome 13, 5 genes on chromosome 20 and 15 genes on chromosome 26. Conserved gene order for the β-defensin genes was apparent in the two smaller clusters, although gene order was reversed on chromosome 2, suggesting an inversion between sheep and cattle. Complete conservation of gene order was also observed for chromosome 13 β-defensin orthologs. More structural differences were apparent between chromosome 26 genes and the orthologous region in the bovine reference genome, which is known to be copy-number variable. In this cluster, the Defensin-beta 1 (DEFB1) gene matched to eleven Bovine Neutrophil beta-Defensin (BNBD) genes on chromosome 27 with almost uniform similarity, as well as to tracheal, enteric and lingual anti-microbial peptides (TAP, EAP and LAP), suggesting that annotation of the bovine reference sequence is still incomplete. qPCR was used to profile the expression of 34 β-defensin genes, representing each of the four clusters, in the ram reproductive tract. Distinct site-specific and differential expression profiles were

  12. Characterization of Three Mycobacterium spp. with Potential Use in Bioremediation by Genome Sequencing and Comparative Genomics.

    Science.gov (United States)

    Das, Sarbashis; Pettersson, B M Fredrik; Behra, Phani Rama Krishna; Ramesh, Malavika; Dasgupta, Santanu; Bhattacharya, Alok; Kirsebom, Leif A

    2015-06-16

    We provide the genome sequences of the type strains of the polychlorophenol-degrading Mycobacterium chlorophenolicum (DSM43826), the degrader of chlorinated aliphatics Mycobacterium chubuense (DSM44219) and Mycobacterium obuense (DSM44075) that has been tested for use in cancer immunotherapy. The genome sizes of M. chlorophenolicum, M. chubuense, and M. obuense are 6.93, 5.95, and 5.58 Mb with GC-contents of 68.4%, 69.2%, and 67.9%, respectively. Comparative genomic analysis revealed that 3,254 genes are common and we predicted approximately 250 genes acquired through horizontal gene transfer from different sources including proteobacteria. The data also showed that the biodegrading Mycobacterium spp. NBB4, also referred to as M. chubuense NBB4, is distantly related to the M. chubuense type strain and should be considered as a separate species, we suggest it to be named Mycobacterium ethylenense NBB4. Among different categories we identified genes with potential roles in: biodegradation of aromatic compounds and copper homeostasis. These are the first nonpathogenic Mycobacterium spp. found harboring genes involved in copper homeostasis. These findings would therefore provide insight into the role of this group of Mycobacterium spp. in bioremediation as well as the evolution of copper homeostasis within the Mycobacterium genus. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  13. phyloXML: XML for evolutionary biology and comparative genomics.

    Science.gov (United States)

    Han, Mira V; Zmasek, Christian M

    2009-10-27

    Evolutionary trees are central to a wide range of biological studies. In many of these studies, tree nodes and branches need to be associated (or annotated) with various attributes. For example, in studies concerned with organismal relationships, tree nodes are associated with taxonomic names, whereas tree branches have lengths and oftentimes support values. Gene trees used in comparative genomics or phylogenomics are usually annotated with taxonomic information, genome-related data, such as gene names and functional annotations, as well as events such as gene duplications, speciations, or exon shufflings, combined with information related to the evolutionary tree itself. The data standards currently used for evolutionary trees have limited capacities to incorporate such annotations of different data types. We developed a XML language, named phyloXML, for describing evolutionary trees, as well as various associated data items. PhyloXML provides elements for commonly used items, such as branch lengths, support values, taxonomic names, and gene names and identifiers. By using "property" elements, phyloXML can be adapted to novel and unforeseen use cases. We also developed various software tools for reading, writing, conversion, and visualization of phyloXML formatted data. PhyloXML is an XML language defined by a complete schema in XSD that allows storing and exchanging the structures of evolutionary trees as well as associated data. More information about phyloXML itself, the XSD schema, as well as tools implementing and supporting phyloXML, is available at http://www.phyloxml.org.

  14. The aggregate site frequency spectrum for comparative population genomic inference.

    Science.gov (United States)

    Xue, Alexander T; Hickerson, Michael J

    2015-12-01

    Understanding how assemblages of species responded to past climate change is a central goal of comparative phylogeography and comparative population genomics, an endeavour that has increasing potential to integrate with community ecology. New sequencing technology now provides the potential to perform complex demographic inference at unprecedented resolution across assemblages of nonmodel species. To this end, we introduce the aggregate site frequency spectrum (aSFS), an expansion of the site frequency spectrum to use single nucleotide polymorphism (SNP) data sets collected from multiple, co-distributed species for assemblage-level demographic inference. We describe how the aSFS is constructed over an arbitrary number of independent population samples and then demonstrate how the aSFS can differentiate various multispecies demographic histories under a wide range of sampling configurations while allowing effective population sizes and expansion magnitudes to vary independently. We subsequently couple the aSFS with a hierarchical approximate Bayesian computation (hABC) framework to estimate degree of temporal synchronicity in expansion times across taxa, including an empirical demonstration with a data set consisting of five populations of the threespine stickleback (Gasterosteus aculeatus). Corroborating what is generally understood about the recent postglacial origins of these populations, the joint aSFS/hABC analysis strongly suggests that the stickleback data are most consistent with synchronous expansion after the Last Glacial Maximum (posterior probability = 0.99). The aSFS will have general application for multilevel statistical frameworks to test models involving assemblages and/or communities, and as large-scale SNP data from nonmodel species become routine, the aSFS expands the potential for powerful next-generation comparative population genomic inference. © 2015 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  15. Asthma-COPD overlap. Clinical relevance of genomic signatures of type 2 inflammation in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Christenson, Stephanie A; Steiling, Katrina; van den Berge, Maarten; Hijazi, Kahkeshan; Hiemstra, Pieter S; Postma, Dirkje S; Lenburg, Marc E; Spira, Avrum; Woodruff, Prescott G

    2015-04-01

    Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease and likely includes a subgroup that is biologically comparable to asthma. Studying asthma-associated gene expression changes in COPD could add insight into COPD pathogenesis and reveal biomarkers that predict a favorable response to corticosteroids. To determine whether asthma-associated gene signatures are increased in COPD and associated with asthma-related features. We compared disease-associated airway epithelial gene expression alterations in an asthma cohort (n = 105) and two COPD cohorts (n = 237, 171). The T helper type 2 (Th2) signature (T2S) score, a gene expression metric induced in Th2-high asthma, was evaluated in these COPD cohorts. The T2S score was correlated with asthma-related features and response to corticosteroids in COPD in a randomized, placebo-controlled trial, the Groningen and Leiden Universities study of Corticosteroids in Obstructive Lung Disease (GLUCOLD; n = 89). The 200 genes most differentially expressed in asthma versus healthy control subjects were enriched among genes associated with more severe airflow obstruction in these COPD cohorts (P COPD cohorts. Higher T2S scores correlated with increased airway wall eosinophil counts (P = 0.003), blood eosinophil percentage (P = 0.03), bronchodilator reversibility (P = 0.01), and improvement in hyperinflation after corticosteroid treatment (P = 0.019) in GLUCOLD. These data identify airway gene expression alterations that can co-occur in asthma and COPD. The association of the T2S score with increased severity and "asthma-like" features (including a favorable corticosteroid response) in COPD suggests that Th2 inflammation is important in a COPD subset that cannot be identified by clinical history of asthma.

  16. Asthma–COPD Overlap. Clinical Relevance of Genomic Signatures of Type 2 Inflammation in Chronic Obstructive Pulmonary Disease

    Science.gov (United States)

    Steiling, Katrina; van den Berge, Maarten; Hijazi, Kahkeshan; Hiemstra, Pieter S.; Postma, Dirkje S.; Lenburg, Marc E.; Spira, Avrum; Woodruff, Prescott G.

    2015-01-01

    Rationale: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease and likely includes a subgroup that is biologically comparable to asthma. Studying asthma-associated gene expression changes in COPD could add insight into COPD pathogenesis and reveal biomarkers that predict a favorable response to corticosteroids. Objectives: To determine whether asthma-associated gene signatures are increased in COPD and associated with asthma-related features. Methods: We compared disease-associated airway epithelial gene expression alterations in an asthma cohort (n = 105) and two COPD cohorts (n = 237, 171). The T helper type 2 (Th2) signature (T2S) score, a gene expression metric induced in Th2-high asthma, was evaluated in these COPD cohorts. The T2S score was correlated with asthma-related features and response to corticosteroids in COPD in a randomized, placebo-controlled trial, the Groningen and Leiden Universities study of Corticosteroids in Obstructive Lung Disease (GLUCOLD; n = 89). Measurements and Main Results: The 200 genes most differentially expressed in asthma versus healthy control subjects were enriched among genes associated with more severe airflow obstruction in these COPD cohorts (P COPD cohorts. Higher T2S scores correlated with increased airway wall eosinophil counts (P = 0.003), blood eosinophil percentage (P = 0.03), bronchodilator reversibility (P = 0.01), and improvement in hyperinflation after corticosteroid treatment (P = 0.019) in GLUCOLD. Conclusions: These data identify airway gene expression alterations that can co-occur in asthma and COPD. The association of the T2S score with increased severity and “asthma-like” features (including a favorable corticosteroid response) in COPD suggests that Th2 inflammation is important in a COPD subset that cannot be identified by clinical history of asthma. PMID:25611785

  17. Advanced Cancer Genomics Institute: Genetic Signatures and Therapeutic Targets in Cancer Progression

    Science.gov (United States)

    2015-04-01

    will use for mouse models of primary tumor and metastasis growth. Fig. 6 is an example in which human T47D breast cancer cells transduced with a...changes (Fig. 8). Figure 6. Example of IVIS imaging of orthotopic injection of T47D -luc2 cells, 2 weeks post-injection in mammary fat pads...of the T47D line. Table 1. RNA-seq analysis of Src-induced genes that contribute to CR-CaP growth. We have compared the Src- and Ack1-induced

  18. Genomic Insights into Cardiomyopathies: A Comparative Cross-Species Review.

    Science.gov (United States)

    Simpson, Siobhan; Rutland, Paul; Rutland, Catrin Sian

    2017-03-21

    In the global human population, the leading cause of non-communicable death is cardiovascular disease. It is predicted that by 2030, deaths attributable to cardiovascular disease will have risen to over 20 million per year. This review compares the cardiomyopathies in both human and non-human animals and identifies the genetic associations for each disorder in each species/taxonomic group. Despite differences between species, advances in human medicine can be gained by utilising animal models of cardiac disease; likewise, gains can be made in animal medicine from human genomic insights. Advances could include undertaking regular clinical checks in individuals susceptible to cardiomyopathy, genetic testing prior to breeding, and careful administration of breeding programmes (in non-human animals), further development of treatment regimes, and drugs and diagnostic techniques.

  19. Cohen syndrome diagnosed using microarray comparative genomic hibridization

    Directory of Open Access Journals (Sweden)

    Saldarriaga-Gil, Wilmar

    2017-10-01

    Full Text Available Cohen syndrome (CS is an uncommon autosomal recessive genetic disorder attributed to damage on VPS13B gene, locus 8q22-q23. Characteristic phenotype consists of intellectual disability, microcephaly, facial dysmorphism, ophthalmic abnormalities, truncal obesity and hipotony. Worldwide, around 150 cases have been published, mostly in Finish patients. We report the case of a 3 year-old male, with short height, craniosynostosis, facial dysmorphism, hipotony, and developmental delay. He was diagnosed with Cohen syndrome using Microarray Comparative Genomic Hibridization (aCGH that showed homozygous deletion of 0.153 Mb on 8q22.2 including VPS13B gene, OMIM #216550. With this report we contribute to enlarge epidemiological databases on an uncommon genetic disorder. Besides, we illustrate on the contribution of aCGH to the etiological diagnosis of patients with unexplained intellectual disability, delayed psychomotor development, language difficulties, autism and multiple congenital anomalies.

  20. Establishing a framework for comparative analysis of genome sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, A.K.

    1995-06-01

    This paper describes a framework and a high-level language toolkit for comparative analysis of genome sequence alignment The framework integrates the information derived from multiple sequence alignment and phylogenetic tree (hypothetical tree of evolution) to derive new properties about sequences. Multiple sequence alignments are treated as an abstract data type. Abstract operations have been described to manipulate a multiple sequence alignment and to derive mutation related information from a phylogenetic tree by superimposing parsimonious analysis. The framework has been applied on protein alignments to derive constrained columns (in a multiple sequence alignment) that exhibit evolutionary pressure to preserve a common property in a column despite mutation. A Prolog toolkit based on the framework has been implemented and demonstrated on alignments containing 3000 sequences and 3904 columns.

  1. Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

    KAUST Repository

    Aranda, Manuel

    2012-09-21

    Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization).

  2. MicroRNA target finding by comparative genomics.

    Science.gov (United States)

    Friedman, Robin C; Burge, Christopher B

    2014-01-01

    MicroRNAs (miRNAs) have been implicated in virtually every metazoan biological process, exerting a widespread impact on gene expression. MicroRNA repression is conferred by relatively short "seed match" sequences, although the degree of repression varies widely for individual target sites. The factors controlling whether, and to what extent, a target site is repressed are not fully understood. As an alternative to target prediction based on sequence alone, comparative genomics has emerged as an invaluable tool for identifying miRNA targets that are conserved by natural selection, and hence likely effective and important. Here we present a general method for quantifying conservation of miRNA seed match sites, separating it from background conservation, controlling for various biases, and predicting miRNA targets. This method is useful not only for generating predictions but also as a tool for empirically evaluating the importance of various target prediction criteria.

  3. Comparative Genome Analysis of Lolium-Festuca Complex Species

    DEFF Research Database (Denmark)

    Czaban, Adrian; Byrne, Stephen; Sharma, Sapna

    2015-01-01

    The Lolium-Festuca complex incorporates species from the Lolium genera and the broad leaf Fescues. Plants belonging to this complex exhibit significant phenotypic plasticity for agriculturally important traits, such as annuality/perenniality, establishment potential, growth speed, nutritional value......, winter hardiness, drought tolerance and resistance to grazing. In this study we have sequenced and assembled the low copy fraction of the genomes of Lolium westerwoldicum, Lolium multiflorum, Festuca pratensis and Lolium temulentum. We have also generated de-novo transcriptome assemblies for each species....... Our dataset enabled us to perform comparative gene family analysis for CBF (C-Repeat Binding Factor) proteins, which are key regulators of cold acclimation and freezing tolerance in plants....

  4. Evolutionary insights into scleractinian corals using comparative genomic hybridizations

    Directory of Open Access Journals (Sweden)

    Aranda Manuel

    2012-09-01

    Full Text Available Abstract Background Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization. Results Our results showed that the current microarray platform for A. palmata is able to provide biological relevant information for a wide variety of coral species covering both the complex clade as well the robust clade. Analysis of the fraction of highly diverged genes showed a significantly higher amount of genes without annotation corroborating previous findings that point towards a higher rate of divergence for taxonomically restricted genes. Among the genes with annotation, we found many mitochondrial genes to be highly diverged in M. faveolata when compared to A. palmata, while the majority of nuclear encoded genes maintained an average divergence rate. Conclusions The use of present microarray platforms for transcriptional analyses in different coral species will greatly enhance the understanding of the molecular basis of stress and health and highlight evolutionary differences between scleractinian coral species. On a genomic basis, we show that cDNA arrays can be used to identify patterns of divergence. Mitochondrion-encoded genes seem to have diverged faster than

  5. Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

    Science.gov (United States)

    Aranda, Manuel; DeSalvo, Michael K; Bayer, Till; Medina, Monica; Voolstra, Christian R

    2012-09-21

    Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization). Our results showed that the current microarray platform for A. palmata is able to provide biological relevant information for a wide variety of coral species covering both the complex clade as well the robust clade. Analysis of the fraction of highly diverged genes showed a significantly higher amount of genes without annotation corroborating previous findings that point towards a higher rate of divergence for taxonomically restricted genes. Among the genes with annotation, we found many mitochondrial genes to be highly diverged in M. faveolata when compared to A. palmata, while the majority of nuclear encoded genes maintained an average divergence rate. The use of present microarray platforms for transcriptional analyses in different coral species will greatly enhance the understanding of the molecular basis of stress and health and highlight evolutionary differences between scleractinian coral species. On a genomic basis, we show that cDNA arrays can be used to identify patterns of divergence. Mitochondrion-encoded genes seem to have diverged faster than nuclear encoded genes in robust corals. Accordingly, this

  6. Comparative Genomic Analyses of the Human NPHP1 Locus Reveal Complex Genomic Architecture and Its Regional Evolution in Primates.

    Directory of Open Access Journals (Sweden)

    Bo Yuan

    2015-12-01

    Full Text Available Many loci in the human genome harbor complex genomic structures that can result in susceptibility to genomic rearrangements leading to various genomic disorders. Nephronophthisis 1 (NPHP1, MIM# 256100 is an autosomal recessive disorder that can be caused by defects of NPHP1; the gene maps within the human 2q13 region where low copy repeats (LCRs are abundant. Loss of function of NPHP1 is responsible for approximately 85% of the NPHP1 cases-about 80% of such individuals carry a large recurrent homozygous NPHP1 deletion that occurs via nonallelic homologous recombination (NAHR between two flanking directly oriented ~45 kb LCRs. Published data revealed a non-pathogenic inversion polymorphism involving the NPHP1 gene flanked by two inverted ~358 kb LCRs. Using optical mapping and array-comparative genomic hybridization, we identified three potential novel structural variant (SV haplotypes at the NPHP1 locus that may protect a haploid genome from the NPHP1 deletion. Inter-species comparative genomic analyses among primate genomes revealed massive genomic changes during evolution. The aggregated data suggest that dynamic genomic rearrangements occurred historically within the NPHP1 locus and generated SV haplotypes observed in the human population today, which may confer differential susceptibility to genomic instability and the NPHP1 deletion within a personal genome. Our study documents diverse SV haplotypes at a complex LCR-laden human genomic region. Comparative analyses provide a model for how this complex region arose during primate evolution, and studies among humans suggest that intra-species polymorphism may potentially modulate an individual's susceptibility to acquiring disease-associated alleles.

  7. Selection signatures in worldwide sheep populations.

    Science.gov (United States)

    Fariello, Maria-Ines; Servin, Bertrand; Tosser-Klopp, Gwenola; Rupp, Rachel; Moreno, Carole; San Cristobal, Magali; Boitard, Simon

    2014-01-01

    The diversity of populations in domestic species offers great opportunities to study genome response to selection. The recently published Sheep HapMap dataset is a great example of characterization of the world wide genetic diversity in sheep. In this study, we re-analyzed the Sheep HapMap dataset to identify selection signatures in worldwide sheep populations. Compared to previous analyses, we made use of statistical methods that (i) take account of the hierarchical structure of sheep populations, (ii) make use of linkage disequilibrium information and (iii) focus specifically on either recent or older selection signatures. We show that this allows pinpointing several new selection signatures in the sheep genome and distinguishing those related to modern breeding objectives and to earlier post-domestication constraints. The newly identified regions, together with the ones previously identified, reveal the extensive genome response to selection on morphology, color and adaptation to new environments.

  8. Automated Comparative Auditing of NCIT Genomic Roles Using NCBI

    Science.gov (United States)

    Cohen, Barry; Oren, Marc; Min, Hua; Perl, Yehoshua; Halper, Michael

    2008-01-01

    Biomedical research has identified many human genes and various knowledge about them. The National Cancer Institute Thesaurus (NCIT) represents such knowledge as concepts and roles (relationships). Due to the rapid advances in this field, it is to be expected that the NCIT’s Gene hierarchy will contain role errors. A comparative methodology to audit the Gene hierarchy with the use of the National Center for Biotechnology Information’s (NCBI’s) Entrez Gene database is presented. The two knowledge sources are accessed via a pair of Web crawlers to ensure up-to-date data. Our algorithms then compare the knowledge gathered from each, identify discrepancies that represent probable errors, and suggest corrective actions. The primary focus is on two kinds of gene-roles: (1) the chromosomal locations of genes, and (2) the biological processes in which genes plays a role. Regarding chromosomal locations, the discrepancies revealed are striking and systematic, suggesting a structurally common origin. In regard to the biological processes, difficulties arise because genes frequently play roles in multiple processes, and processes may have many designations (such as synonymous terms). Our algorithms make use of the roles defined in the NCIT Biological Process hierarchy to uncover many probable gene-role errors in the NCIT. These results show that automated comparative auditing is a promising technique that can identify a large number of probable errors and corrections for them in a terminological genomic knowledge repository, thus facilitating its overall maintenance. PMID:18486558

  9. Comparative genomics reveals evidence of marine adaptation in Salinispora species

    Directory of Open Access Journals (Sweden)

    Penn Kevin

    2012-03-01

    Full Text Available Abstract Background Actinobacteria represent a consistent component of most marine bacterial communities yet little is known about the mechanisms by which these Gram-positive bacteria adapt to life in the marine environment. Here we employed a phylogenomic approach to identify marine adaptation genes in marine Actinobacteria. The focus was on the obligate marine actinomycete genus Salinispora and the identification of marine adaptation genes that have been acquired from other marine bacteria. Results Functional annotation, comparative genomics, and evidence of a shared evolutionary history with bacteria from hyperosmotic environments were used to identify a pool of more than 50 marine adaptation genes. An Actinobacterial species tree was used to infer the likelihood of gene gain or loss in accounting for the distribution of each gene. Acquired marine adaptation genes were associated with electron transport, sodium and ABC transporters, and channels and pores. In addition, the loss of a mechanosensitive channel gene appears to have played a major role in the inability of Salinispora strains to grow following transfer to low osmotic strength media. Conclusions The marine Actinobacteria for which genome sequences are available are broadly distributed throughout the Actinobacterial phylogenetic tree and closely related to non-marine forms suggesting they have been independently introduced relatively recently into the marine environment. It appears that the acquisition of transporters in Salinispora spp. represents a major marine adaptation while gene loss is proposed to play a role in the inability of this genus to survive outside of the marine environment. This study reveals fundamental differences between marine adaptations in Gram-positive and Gram-negative bacteria and no common genetic basis for marine adaptation among the Actinobacteria analyzed.

  10. Comparative genomics and transduction potential of Enterococcus faecalis temperate bacteriophages.

    Science.gov (United States)

    Yasmin, Azra; Kenny, John G; Shankar, Jayendra; Darby, Alistair C; Hall, Neil; Edwards, Clive; Horsburgh, Malcolm J

    2010-02-01

    To determine the relative importance of temperate bacteriophage in the horizontal gene transfer of fitness and virulence determinants of Enterococcus faecalis, a panel of 47 bacteremia isolates were treated with the inducing agents mitomycin C, norfloxacin, and UV radiation. Thirty-four phages were purified from culture supernatants and discriminated using pulsed-field gel electrophoresis (PFGE) and restriction mapping. From these analyses the genomes of eight representative phages were pyrosequenced, revealing four distinct groups of phages. Three groups of phages, PhiFL1 to 3, were found to be sequence related, with PhiFL1A to C and PhiFL2A and B sharing the greatest identity (87 to 88%), while PhiFL3A and B share 37 to 41% identity with PhiFL1 and 2. PhiFL4A shares 3 to 12% identity with the phages PhiFL1 to 3. The PhiFL3A and B phages possess a high DNA sequence identity with the morphogenesis and lysis modules of Lactococcus lactis subsp. cremoris prophages. Homologs of the Streptococcus mitis platelet binding phage tail proteins, PblA and PblB, are encoded on each sequenced E. faecalis phage. Few other phage genes encoding potential virulence functions were identified, and there was little evidence of carriage of lysogenic conversion genes distal to endolysin, as has been observed with genomes of many temperate phages from the opportunist pathogens Staphylococcus aureus and Streptococcus pyogenes. E. faecalis JH2-2 lysogens were generated using the eight phages, and these were examined for their relative fitness in Galleria mellonella. Several lysogens exhibited different effects upon survival of G. mellonella compared to their isogenic parent. The eight phages were tested for their ability to package host DNA, and three were shown to be very effective for generalized transduction of naive host cells of the laboratory strains OG1RF and JH2-2.

  11. Genome sequence analyses of Pseudomonas savastanoi pv. glycinea and subtractive hybridization-based comparative genomics with nine pseudomonads.

    Science.gov (United States)

    Qi, Mingsheng; Wang, Dongping; Bradley, Carl A; Zhao, Youfu

    2011-01-27

    Bacterial blight, caused by Pseudomonas savastanoi pv. glycinea (Psg), is a common disease of soybean. In an effort to compare a current field isolate with one isolated in the early 1960s, the genomes of two Psg strains, race 4 and B076, were sequenced using 454 pyrosequencing. The genomes of both Psg strains share more than 4,900 highly conserved genes, indicating very low genetic diversity between Psg genomes. Though conserved, genome rearrangements and recombination events occur commonly within the two Psg genomes. When compared to each other, 437 and 163 specific genes were identified in B076 and race 4, respectively. Most specific genes are plasmid-borne, indicating that acquisition and maintenance of plasmids may represent a major mechanism to change the genetic composition of the genome and even acquire new virulence factors. Type three secretion gene clusters of Psg strains are near identical with that of P. savastanoi pv. phaseolicola (Pph) strain 1448A and they shared 20 common effector genes. Furthermore, the coronatine biosynthetic cluster is present on a large plasmid in strain B076, but not in race 4. In silico subtractive hybridization-based comparative genomic analyses with nine sequenced phytopathogenic pseudomonads identified dozens of specific islands (SIs), and revealed that the genomes of Psg strains are more similar to those belonging to the same genomospecies such as Pph 1448A than to other phytopathogenic pseudomonads. The number of highly conserved genes (core genome) among them decreased dramatically when more genomes were included in the subtraction, suggesting the diversification of pseudomonads, and further indicating the genome heterogeneity among pseudomonads. However, the number of specific genes did not change significantly, suggesting these genes are indeed specific in Psg genomes. These results reinforce the idea of a species complex of P. syringae and support the reclassification of P. syringae into different species.

  12. Comparative Evaluation of Preprocessing Freeware on Chromatography/Mass Spectrometry Data for Signature Discovery

    Energy Technology Data Exchange (ETDEWEB)

    Coble, Jamie B.; Fraga, Carlos G.

    2014-07-07

    Preprocessing software is crucial for the discovery of chemical signatures in metabolomics, chemical forensics, and other signature-focused disciplines that involve analyzing large data sets from chemical instruments. Here, four freely available and published preprocessing tools known as metAlign, MZmine, SpectConnect, and XCMS were evaluated for impurity profiling using nominal mass GC/MS data and accurate mass LC/MS data. Both data sets were previously collected from the analysis of replicate samples from multiple stocks of a nerve-agent precursor. Each of the four tools had their parameters set for the untargeted detection of chromatographic peaks from impurities present in the stocks. The peak table generated by each preprocessing tool was analyzed to determine the number of impurity components detected in all replicate samples per stock. A cumulative set of impurity components was then generated using all available peak tables and used as a reference to calculate the percent of component detections for each tool, in which 100% indicated the detection of every component. For the nominal mass GC/MS data, metAlign performed the best followed by MZmine, SpectConnect, and XCMS with detection percentages of 83, 60, 47, and 42%, respectively. For the accurate mass LC/MS data, the order was metAlign, XCMS, and MZmine with detection percentages of 80, 45, and 35%, respectively. SpectConnect did not function for the accurate mass LC/MS data. Larger detection percentages were obtained by combining the top performer with at least one of the other tools such as 96% by combining metAlign with MZmine for the GC/MS data and 93% by combining metAlign with XCMS for the LC/MS data. In terms of quantitative performance, the reported peak intensities had average absolute biases of 41, 4.4, 1.3 and 1.3% for SpectConnect, metAlign, XCMS, and MZmine, respectively, for the GC/MS data. For the LC/MS data, the average absolute biases were 22, 4.5, and 3.1% for metAlign, MZmine, and XCMS

  13. Microbial comparative pan-genomics using binomial mixture models

    DEFF Research Database (Denmark)

    Ussery, David; Snipen, L; Almøy, T

    2009-01-01

    The size of the core- and pan-genome of bacterial species is a topic of increasing interest due to the growing number of sequenced prokaryote genomes, many from the same species. Attempts to estimate these quantities have been made, using regression methods or mixture models. We extend the latter...... occurring genes in the population. CONCLUSION: Analyzing pan-genomics data with binomial mixture models is a way to handle dependencies between genomes, which we find is always present. A bottleneck in the estimation procedure is the annotation of rarely occurring genes....

  14. The Use of MPSS for Whole-Genome Transcriptional Analysis in Arabidopsis

    Science.gov (United States)

    Meyers, Blake C.; Tej, Shivakundan Singh; Vu, Tam H.; Haudenschild, Christian D.; Agrawal, Vikas; Edberg, Steve B.; Ghazal, Hassan; Decola, Shannon

    2004-01-01

    We have generated 36,991,173 17-base sequence “signatures” representing transcripts from the model plant Arabidopsis. These data were derived by massively parallel signature sequencing (MPSS) from 14 libraries and comprised 268,132 distinct sequences. Comparable data were also obtained with 20-base signatures. We developed a method for handling these data and for comparing these signatures to the annotated Arabidopsis genome. As part of this procedure, 858,019 potential or “genomic” signatures were extracted from the Arabidopsis genome and classified based on the position and orientation of the signatures relative to annotated genes. A comparison of genomic and expressed signatures matched 67,735 signatures predicted to be derived from distinct transcripts and expressed at significant levels. Expressed signatures were derived from the sense strand of at least 19,088 of 29,084 annotated genes. A comparison of the genomic and expression signatures demonstrated that ∼7.7% of genomic signatures were underrepresented in the expression data. These genomic signatures contained one of 20 four-base words that were consistently associated with reduced MPSS abundances. More than 89% of the sum of the expressed signature abundances matched the Arabidopsis genome, and many of the unmatched signatures found in high abundances were predicted to match to previously uncharacterized transcripts. PMID:15289482

  15. Genome Stability of Lyme Disease Spirochetes: Comparative Genomics of Borrelia burgdorferi Plasmids

    Energy Technology Data Exchange (ETDEWEB)

    Casjens S. R.; Dunn J.; Mongodin, E. F.; Qiu, W.-G.; Luft, B. J.; Schutzer, S. E.; Gilcrease, E. B.; Huang, W. M.; Vujadinovic, M.; Aron, J. K.; Vargas, L. C.; Freeman, S.; Radune, D.; Weidman, J. F.; Dimitrov, G. I.; Khouri, H. M.; Sosa, J. E.; Halpin, R. A.; Fraser, C. M.

    2012-03-14

    Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33-40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi {approx}900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short {le}20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant.

  16. Genome Stability of Lyme Disease Spirochetes: Comparative Genomics of Borrelia burgdorferi Plasmids

    Science.gov (United States)

    Casjens, Sherwood R.; Mongodin, Emmanuel F.; Qiu, Wei-Gang; Luft, Benjamin J.; Schutzer, Steven E.; Gilcrease, Eddie B.; Huang, Wai Mun; Vujadinovic, Marija; Aron, John K.; Vargas, Levy C.; Freeman, Sam; Radune, Diana; Weidman, Janice F.; Dimitrov, George I.; Khouri, Hoda M.; Sosa, Julia E.; Halpin, Rebecca A.; Dunn, John J.; Fraser, Claire M.

    2012-01-01

    Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33–40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi ∼900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short ≤20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant. PMID:22432010

  17. Genome-wide oligonucleotide-based array comparative genome hybridization analysis of non-isolated congenital diaphragmatic hernia

    NARCIS (Netherlands)

    D.A. Scott; M. Klaassens; A.M. Holder (Ashley); K.P. Lally (Kevin); C.J. Fernandes (Caraciolo); R-J.H. Galjaard (Robert-Jan); D. Tibboel (Dick); J.E.M.M. de Klein (Annelies); B. Lee (Brendan)

    2007-01-01

    textabstractNon-isolated congenital diaphragmatic hernia (CDH+) is a severe birth defect that is often caused by de novo chromosomal anomalies. In this report, we use genome-wide oligonucleotide-based array comparative genome hybridization (aCGH) followed by rapid real-time quantitative PCR analysis

  18. Comparative Functional Genomics of Lactobacillus spp. Reveals Possible Mechanisms for Specialization of Vaginal Lactobacilli to Their Environment

    Science.gov (United States)

    Suzuki, Haruo; Hickey, Roxana J.; Forney, Larry J.

    2014-01-01

    Lactobacilli are found in a wide variety of habitats. Four species, Lactobacillus crispatus, L. gasseri, L. iners, and L. jensenii, are common and abundant in the human vagina and absent from other habitats. These may be adapted to the vagina and possess characteristics enabling them to thrive in that environment. Furthermore, stable codominance of multiple Lactobacillus species in a single community is infrequently observed. Thus, it is possible that individual vaginal Lactobacillus species possess unique characteristics that confer to them host-specific competitive advantages. We performed comparative functional genomic analyses of representatives of 25 species of Lactobacillus, searching for habitat-specific traits in the genomes of the vaginal lactobacilli. We found that the genomes of the vaginal species were significantly smaller and had significantly lower GC content than those of the nonvaginal species. No protein families were found to be specific to the vaginal species analyzed, but some were either over- or underrepresented relative to nonvaginal species. We also found that within the vaginal species, each genome coded for species-specific protein families. Our results suggest that even though the vaginal species show no general signatures of adaptation to the vaginal environment, each species has specific and perhaps unique ways of interacting with its environment, be it the host or other microbes in the community. These findings will serve as a foundation for further exploring the role of lactobacilli in the ecological dynamics of vaginal microbial communities and their ultimate impact on host health. PMID:24488312

  19. Comparing Genomic Profiles of Women With and Without Fibromyalgia

    Science.gov (United States)

    Lukkahatai, Nada; Walitt, Brian; Espina, Alexandra; Wang, Dan; Saligan, Leorey N.

    2016-01-01

    Background Fibromyalgia syndrome (FMS), a chronic musculoskeletal condition characterized by diffuse pain, fatigue, sleep impairment, and cognitive dysfunction, is associated with significant functional disability. Its underlying biological mechanisms are unknown. This study investigated differentially expressed genes between women with FMS and healthy volunteers. Methods Women who met the 1990 or 2010 American College of Rheumatology fibromyalgia criteria were compared to age- and race-matched pain-free healthy women. Peripheral blood samples were collected, and a full genome microarray gene expression analysis was performed. One-way analysis of variance was used to identify differentially expressed genes using the filtering criterion of 1% false discovery rate. Analysis of canonical pathways associated with these genes was performed. Confirmatory quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay verified microarray results. Independent t-tests compared gene and protein expression between groups. Result Participants were 54 women with FMS and 25 controls. Expression arrays from a subset of women with FMS (n = 29) and controls (n = 20) showed upregulation of 12 genes (>1.8-fold change, p immune response, and homeostasis appears to be relevant to the experience of FMS. Replication and exploration of the relationship between gene expression and symptom severity will help determine clinical relevance of these findings. PMID:26015072

  20. Comparative Genomics of Methanopyrus sp. SNP6 and KOL6 Revealing Genomic Regions of Plasticity Implicated in Extremely Thermophilic Profiles

    Directory of Open Access Journals (Sweden)

    Zhiliang Yu

    2017-07-01

    Full Text Available Methanopyrus spp. are usually isolated from harsh niches, such as high osmotic pressure and extreme temperature. However, the molecular mechanisms for their environmental adaption are poorly understood. Archaeal species is commonly considered as primitive organism. The evolutional placement of archaea is a fundamental and intriguing scientific question. We sequenced the genomes of Methanopyrus strains SNP6 and KOL6 isolated from the Atlantic and Iceland, respectively. Comparative genomic analysis revealed genetic diversity and instability implicated in niche adaption, including a number of transporter- and integrase/transposase-related genes. Pan-genome analysis also defined the gene pool of Methanopyrus spp., in addition of ~120-Kb genomic region of plasticity impacting cognate genomic architecture. We believe that Methanopyrus genomics could facilitate efficient investigation/recognition of archaeal phylogenetic diverse patterns, as well as improve understanding of biological roles and significance of these versatile microbes.

  1. CrusView: a Java-based visualization platform for comparative genomics analyses in Brassicaceae species.

    Science.gov (United States)

    Chen, Hao; Wang, Xiangfeng

    2013-09-01

    In plants and animals, chromosomal breakage and fusion events based on conserved syntenic genomic blocks lead to conserved patterns of karyotype evolution among species of the same family. However, karyotype information has not been well utilized in genomic comparison studies. We present CrusView, a Java-based bioinformatic application utilizing Standard Widget Toolkit/Swing graphics libraries and a SQLite database for performing visualized analyses of comparative genomics data in Brassicaceae (crucifer) plants. Compared with similar software and databases, one of the unique features of CrusView is its integration of karyotype information when comparing two genomes. This feature allows users to perform karyotype-based genome assembly and karyotype-assisted genome synteny analyses with preset karyotype patterns of the Brassicaceae genomes. Additionally, CrusView is a local program, which gives its users high flexibility when analyzing unpublished genomes and allows users to upload self-defined genomic information so that they can visually study the associations between genome structural variations and genetic elements, including chromosomal rearrangements, genomic macrosynteny, gene families, high-frequency recombination sites, and tandem and segmental duplications between related species. This tool will greatly facilitate karyotype, chromosome, and genome evolution studies using visualized comparative genomics approaches in Brassicaceae species. CrusView is freely available at http://www.cmbb.arizona.edu/CrusView/.

  2. Genome-wide array comparative genomic hybridization analysis reveals distinct amplifications in osteosarcoma

    International Nuclear Information System (INIS)

    Man, Tsz-Kwong; Rao, Pulivarthi H; Lu, Xin-Yan; Jaeweon, Kim; Perlaky, Laszlo; Harris, Charles P; Shah, Shishir; Ladanyi, Marc; Gorlick, Richard; Lau, Ching C

    2004-01-01

    Osteosarcoma is a highly malignant bone neoplasm of children and young adults. It is characterized by extremely complex karyotypes and high frequency of chromosomal amplifications. Currently, only the histological response (degree of necrosis) to therapy represent gold standard for predicting the outcome in a patient with non-metastatic osteosarcoma at the time of definitive surgery. Patients with lower degree of necrosis have a higher risk of relapse and poor outcome even after chemotherapy and complete resection of the primary tumor. Therefore, a better understanding of the underlying molecular genetic events leading to tumor initiation and progression could result in the identification of potential diagnostic and therapeutic targets. We used a genome-wide screening method – array based comparative genomic hybridization (array-CGH) to identify DNA copy number changes in 48 patients with osteosarcoma. We applied fluorescence in situ hybridization (FISH) to validate some of amplified clones in this study. Clones showing gains (79%) were more frequent than losses (66%). High-level amplifications and homozygous deletions constitute 28.6% and 3.8% of tumor genome respectively. High-level amplifications were present in 238 clones, of which about 37% of them showed recurrent amplification. Most frequently amplified clones were mapped to 1p36.32 (PRDM16), 6p21.1 (CDC5L, HSPCB, NFKBIE), 8q24, 12q14.3 (IFNG), 16p13 (MGRN1), and 17p11.2 (PMP22 MYCD, SOX1,ELAC27). We validated some of the amplified clones by FISH from 6p12-p21, 8q23-q24, and 17p11.2 amplicons. Homozygous deletions were noted for 32 clones and only 7 clones showed in more than one case. These 7 clones were mapped to 1q25.1 (4 cases), 3p14.1 (4 cases), 13q12.2 (2 cases), 4p15.1 (2 cases), 6q12 (2 cases), 6q12 (2 cases) and 6q16.3 (2 cases). This study clearly demonstrates the utility of array CGH in defining high-resolution DNA copy number changes and refining amplifications. The resolution of array CGH

  3. Comparative Genomic Analysis of Meningitis- and Bacteremia-Causing Pneumococci Identifies a Common Core Genome.

    Science.gov (United States)

    Kulohoma, Benard W; Cornick, Jennifer E; Chaguza, Chrispin; Yalcin, Feyruz; Harris, Simon R; Gray, Katherine J; Kiran, Anmol M; Molyneux, Elizabeth; French, Neil; Parkhill, Julian; Faragher, Brian E; Everett, Dean B; Bentley, Stephen D; Heyderman, Robert S

    2015-10-01

    Streptococcus pneumoniae is a nasopharyngeal commensal that occasionally invades normally sterile sites to cause bloodstream infection and meningitis. Although the pneumococcal population structure and evolutionary genetics are well defined, it is not clear whether pneumococci that cause meningitis are genetically distinct from those that do not. Here, we used whole-genome sequencing of 140 isolates of S. pneumoniae recovered from bloodstream infection (n = 70) and meningitis (n = 70) to compare their genetic contents. By fitting a double-exponential decaying-function model, we show that these isolates share a core of 1,427 genes (95% confidence interval [CI], 1,425 to 1,435 genes) and that there is no difference in the core genome or accessory gene content from these disease manifestations. Gene presence/absence alone therefore does not explain the virulence behavior of pneumococci that reach the meninges. Our analysis, however, supports the requirement of a range of previously described virulence factors and vaccine candidates for both meningitis- and bacteremia-causing pneumococci. This high-resolution view suggests that, despite considerable competency for genetic exchange, all pneumococci are under considerable pressure to retain key components advantageous for colonization and transmission and that these components are essential for access to and survival in sterile sites. Copyright © 2015 Kulohoma et al.

  4. Comparative Genomic Analysis of Meningitis- and Bacteremia-Causing Pneumococci Identifies a Common Core Genome

    Science.gov (United States)

    Cornick, Jennifer E.; Chaguza, Chrispin; Yalcin, Feyruz; Harris, Simon R.; Gray, Katherine J.; Kiran, Anmol M.; Molyneux, Elizabeth; French, Neil; Faragher, Brian E.; Everett, Dean B.; Bentley, Stephen D.

    2015-01-01

    Streptococcus pneumoniae is a nasopharyngeal commensal that occasionally invades normally sterile sites to cause bloodstream infection and meningitis. Although the pneumococcal population structure and evolutionary genetics are well defined, it is not clear whether pneumococci that cause meningitis are genetically distinct from those that do not. Here, we used whole-genome sequencing of 140 isolates of S. pneumoniae recovered from bloodstream infection (n = 70) and meningitis (n = 70) to compare their genetic contents. By fitting a double-exponential decaying-function model, we show that these isolates share a core of 1,427 genes (95% confidence interval [CI], 1,425 to 1,435 genes) and that there is no difference in the core genome or accessory gene content from these disease manifestations. Gene presence/absence alone therefore does not explain the virulence behavior of pneumococci that reach the meninges. Our analysis, however, supports the requirement of a range of previously described virulence factors and vaccine candidates for both meningitis- and bacteremia-causing pneumococci. This high-resolution view suggests that, despite considerable competency for genetic exchange, all pneumococci are under considerable pressure to retain key components advantageous for colonization and transmission and that these components are essential for access to and survival in sterile sites. PMID:26259813

  5. Comparative Genome Analysis Reveals Divergent Genome Size Evolution in a Carnivorous Plant Genus

    Directory of Open Access Journals (Sweden)

    Giang T. H. Vu

    2015-11-01

    Full Text Available The C-value paradox remains incompletely resolved after >40 yr and is exemplified by 2,350-fold variation in genome sizes of flowering plants. The carnivorous Lentibulariaceae genus , displaying a 25-fold range of genome sizes, is a promising subject to study mechanisms and consequences of evolutionary genome size variation. Applying genomic, phylogenetic, and cytogenetic approaches, we uncovered bidirectional genome size evolution within the genus . The Steyerm. genome (86 Mbp has probably shrunk by retroelement silencing and deletion-biased double-strand break (DSB repair, from an ancestral size of 400 to 800 Mbp to become one of the smallest among flowering plants. The Stapf genome has expanded by whole-genome duplication (WGD and retrotransposition to 1550 Mbp. became allotetraploid after the split from the clade ∼29 Ma. A. St.-Hil. (179 Mbp, a close relative of , proved to be a recent (autotetraploid. Our analyses suggest a common ancestor of the genus a with an intermediate 1C value (400–800 Mbp and subsequent rapid genome size evolution in opposite directions. Many abundant repeats of the larger genome are absent in the smaller, casting doubt on their functionality for the organism, while recurrent WGD seems to safeguard against the loss of essential elements in the face of genome shrinkage. We cannot identify any consistent differences in habitat or life strategy that correlate with genome size changes, raising the possibility that these changes may be selectively neutral.

  6. New genomic resources for switchgrass: a BAC library and comparative analysis of homoeologous genomic regions harboring bioenergy traits

    Directory of Open Access Journals (Sweden)

    Feltus Frank A

    2011-07-01

    Full Text Available Abstract Background Switchgrass, a C4 species and a warm-season grass native to the prairies of North America, has been targeted for development into an herbaceous biomass fuel crop. Genetic improvement of switchgrass feedstock traits through marker-assisted breeding and biotechnology approaches calls for genomic tools development. Establishment of integrated physical and genetic maps for switchgrass will accelerate mapping of value added traits useful to breeding programs and to isolate important target genes using map based cloning. The reported polyploidy series in switchgrass ranges from diploid (2X = 18 to duodecaploid (12X = 108. Like in other large, repeat-rich plant genomes, this genomic complexity will hinder whole genome sequencing efforts. An extensive physical map providing enough information to resolve the homoeologous genomes would provide the necessary framework for accurate assembly of the switchgrass genome. Results A switchgrass BAC library constructed by partial digestion of nuclear DNA with EcoRI contains 147,456 clones covering the effective genome approximately 10 times based on a genome size of 3.2 Gigabases (~1.6 Gb effective. Restriction digestion and PFGE analysis of 234 randomly chosen BACs indicated that 95% of the clones contained inserts, ranging from 60 to 180 kb with an average of 120 kb. Comparative sequence analysis of two homoeologous genomic regions harboring orthologs of the rice OsBRI1 locus, a low-copy gene encoding a putative protein kinase and associated with biomass, revealed that orthologous clones from homoeologous chromosomes can be unambiguously distinguished from each other and correctly assembled to respective fingerprint contigs. Thus, the data obtained not only provide genomic resources for further analysis of switchgrass genome, but also improve efforts for an accurate genome sequencing strategy. Conclusions The construction of the first switchgrass BAC library and comparative analysis of

  7. Comparative genomics of the relationship between gene structure and expression

    NARCIS (Netherlands)

    Ren, X.

    2006-01-01

    The relationship between the structure of genes and their expression is a relatively new aspect of genome organization and regulation. With more genome sequences and expression data becoming available, bioinformatics approaches can help the further elucidation of the relationships between gene

  8. Comparative genomic data of the Avian Phylogenomics Project

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Bo; Li, Cai

    2014-01-01

    , which include 38 newly sequenced avian genomes plus previously released or simultaneously released genomes of Chicken, Zebra finch, Turkey, Pigeon, Peregrine falcon, Duck, Budgerigar, Adelie penguin, Emperor penguin and the Medium Ground Finch. We hope that this resource will serve future efforts...

  9. Characterization of Mycobacterium chelonae-Like Strains by Comparative Genomics

    Directory of Open Access Journals (Sweden)

    Christiane L. Nogueira

    2017-05-01

    Full Text Available Isolates of the Mycobacterium chelonae-M. abscessus complex are subdivided into four clusters (CHI to CHIV in the INNO-LiPA® Mycobacterium spp DNA strip assay. A considerable phenotypic variability was observed among isolates of the CHII cluster. In this study, we examined the diversity of 26 CHII cluster isolates by phenotypic analysis, drug susceptibility testing, whole genome sequencing and single-gene analysis. Pairwise genome comparisons were performed using several approaches, including average nucleotide identity (ANI and genome-to-genome distance (GGD among others. Based on ANI and GGD the isolates were identified as M. chelonae (14 isolates, M. franklinii (2 isolates and M. salmoniphium (1 isolate. The remaining 9 isolates were subdivided into three novel putative genomospecies. Phenotypic analyses including drug susceptibility testing, as well as whole genome comparison by TETRA and delta differences, were not helpful in separating the groups revealed by ANI and GGD. The analysis of standard four conserved genomic regions showed that rpoB alone and the concatenated sequences clearly distinguished the taxonomic groups delimited by whole genome analyses. In conclusion, the CHII INNO-LiPa is not a homogeneous cluster; on the contrary, it is composed of closely related different species belonging to the M. chelonae-M. abscessus complex and also several unidentified isolates. The detection of these isolates, putatively novel species, indicates a wider inner variability than the presently known in this complex.

  10. Serological evaluation of Mycobacterium ulcerans antigens identified by comparative genomics.

    Directory of Open Access Journals (Sweden)

    Sacha J Pidot

    Full Text Available A specific and sensitive serodiagnostic test for Mycobacterium ulcerans infection would greatly assist the diagnosis of Buruli ulcer and would also facilitate seroepidemiological surveys. By comparative genomics, we identified 45 potential M. ulcerans specific proteins, of which we were able to express and purify 33 in E. coli. Sera from 30 confirmed Buruli ulcer patients, 24 healthy controls from the same endemic region and 30 healthy controls from a non-endemic region in Benin were screened for antibody responses to these specific proteins by ELISA. Serum IgG responses of Buruli ulcer patients were highly variable, however, seven proteins (MUP045, MUP057, MUL_0513, Hsp65, and the polyketide synthase domains ER, AT propionate, and KR A showed a significant difference between patient and non-endemic control antibody responses. However, when sera from the healthy control subjects living in the same Buruli ulcer endemic area as the patients were examined, none of the proteins were able to discriminate between these two groups. Nevertheless, six of the seven proteins showed an ability to distinguish people living in an endemic area from those in a non-endemic area with an average sensitivity of 69% and specificity of 88%, suggesting exposure to M. ulcerans. Further validation of these six proteins is now underway to assess their suitability for use in Buruli ulcer seroepidemiological studies. Such studies are urgently needed to assist efforts to uncover environmental reservoirs and understand transmission pathways of the M. ulcerans.

  11. Comparative transcriptional and genomic analysis of Plasmodium falciparum field isolates.

    Directory of Open Access Journals (Sweden)

    Margaret J Mackinnon

    2009-10-01

    Full Text Available Mechanisms for differential regulation of gene expression may underlie much of the phenotypic variation and adaptability of malaria parasites. Here we describe transcriptional variation among culture-adapted field isolates of Plasmodium falciparum, the species responsible for most malarial disease. It was found that genes coding for parasite protein export into the red cell cytosol and onto its surface, and genes coding for sexual stage proteins involved in parasite transmission are up-regulated in field isolates compared with long-term laboratory isolates. Much of this variability was associated with the loss of small or large chromosomal segments, or other forms of gene copy number variation that are prevalent in the P. falciparum genome (copy number variants, CNVs. Expression levels of genes inside these segments were correlated to that of genes outside and adjacent to the segment boundaries, and this association declined with distance from the CNV boundary. This observation could not be explained by copy number variation in these adjacent genes. This suggests a local-acting regulatory role for CNVs in transcription of neighboring genes and helps explain the chromosomal clustering that we observed here. Transcriptional co-regulation of physical clusters of adaptive genes may provide a way for the parasite to readily adapt to its highly heterogeneous and strongly selective environment.

  12. Low Signature Tent Structures

    National Research Council Canada - National Science Library

    Cox, Randy

    1998-01-01

    .... Modeling shows that visual, near infrared, thermal, and radar signatures should be reduced when compared to other current tent designs. A brief treatise on the role of tent signatures and their results is included.

  13. Identification of Genomic Signatures for the Design of Assays for the Detection and Monitoring of Anthrax Threats

    National Research Council Canada - National Science Library

    Draghici, Sorin; Khatri, Purvesh; Liu, Yanhong; Chase, Kitty J; Bode, Elizabeth A; Kulesh, David A; Wasieloski, Leonard P; Norwood, David A; Reifman, Jaques

    2005-01-01

    .... Such DNA signatures are particularly important for the identification of genetic source of drug resistance of a strain or for the detection of organisms that can be used as biological agents in warfare or terrorism...

  14. Comparative analysis of genome maintenance genes in naked mole rat, mouse, and human

    NARCIS (Netherlands)

    S.L. Macrae (Sheila L.); Q. Zhang (Quanwei); C. Lemetre (Christophe); I. Seim (Inge); R.B. Calder (Robert B.); J.H.J. Hoeijmakers (Jan); Y. Suh (Yousin); V.N. Gladyshev (Vadim N.); A. Seluanov (Andrei); V. Gorbunova (Vera); J. Vijg (Jan); Z.D. Zhang (Zhengdong D.)

    2015-01-01

    textabstractGenome maintenance (GM) is an essential defense system against aging and cancer, as both are characterized by increased genome instability. Here, we compared the copy number variation and mutation rate of 518 GM-associated genes in the naked mole rat (NMR), mouse, and human genomes. GM

  15. In silico comparative genomic analysis of GABAA receptor transcriptional regulation

    Directory of Open Access Journals (Sweden)

    Joyce Christopher J

    2007-06-01

    Full Text Available Abstract Background Subtypes of the GABAA receptor subunit exhibit diverse temporal and spatial expression patterns. In silico comparative analysis was used to predict transcriptional regulatory features in individual mammalian GABAA receptor subunit genes, and to identify potential transcriptional regulatory components involved in the coordinate regulation of the GABAA receptor gene clusters. Results Previously unreported putative promoters were identified for the β2, γ1, γ3, ε, θ and π subunit genes. Putative core elements and proximal transcriptional factors were identified within these predicted promoters, and within the experimentally determined promoters of other subunit genes. Conserved intergenic regions of sequence in the mammalian GABAA receptor gene cluster comprising the α1, β2, γ2 and α6 subunits were identified as potential long range transcriptional regulatory components involved in the coordinate regulation of these genes. A region of predicted DNase I hypersensitive sites within the cluster may contain transcriptional regulatory features coordinating gene expression. A novel model is proposed for the coordinate control of the gene cluster and parallel expression of the α1 and β2 subunits, based upon the selective action of putative Scaffold/Matrix Attachment Regions (S/MARs. Conclusion The putative regulatory features identified by genomic analysis of GABAA receptor genes were substantiated by cross-species comparative analysis and now require experimental verification. The proposed model for the coordinate regulation of genes in the cluster accounts for the head-to-head orientation and parallel expression of the α1 and β2 subunit genes, and for the disruption of transcription caused by insertion of a neomycin gene in the close vicinity of the α6 gene, which is proximal to a putative critical S/MAR.

  16. Functional and Comparative Genomics of Lignocellulose Degradation by Schizophyllum commune

    Energy Technology Data Exchange (ETDEWEB)

    Ohm, Robin A.; Lee, Hanbyul; Park, Hongjae; Brewer, Heather M.; Carver, Akiko; Copeland, Alex; Grimwood, Jane; Lindquist, Erika; Lipzen, Anna; Martin, Joel; Purvine, Samuel O.; Schackwitz, Wendy; Tegelaar, Martin; Tritt, Andrew; Baker, Scott; Choi, In-Geol; Lugones, Luis G.; Wosten, Han A. B.; Grigoriev, Igor V.

    2014-03-14

    The Basidiomycete fungus Schizophyllum commune is a wood-decaying fungus and is used as a model system to study lignocellulose degradation. Version 3.0 of the genome assembly filled 269 of 316 sequence gaps and added 680 kb of sequence. This new assembly was reannotated using RNAseq transcriptomics data, and this resulted in 3110 (24percent) more genes. Two additional S. commune strains with different wood-decaying properties were sequenced, from Tattone (France) and Loenen (The Netherlands). Sequence comparison shows remarkably high sequence diversity between the strains. The overall SNP rate of > 100 SNPs/kb is among the highest rates of within-species polymorphisms in Basidiomycetes. Some well-described proteins like hydrophobins and transcription factors have less than 70percent sequence identity among the strains. Some chromosomes are better conserved than others and in some cases large parts of chromosomes are missing from one or more strains. Gene expression on glucose, cellulose and wood was analyzed in two S. commune strains. Overall, gene expression correlated between the two strains, but there were some notable exceptions. Of particular interest are CAZymes (carbohydrate-active enzymes) that are regulated in different ways in the different strains. In both strains the transcription factor Fsp1 was strongly up-regulated during growth on cellulose and wood, when compared to glucose. Over-expression of Fsp1 using a constitutive promoter resulted in higher cellulose and xylose-degrading enzyme activity, which suggests that Fsp1 is involved in regulating CAZyme gene expression. Two CAZyme genes (of family GH61 and GH11) were shown to be strongly up-regulated during growth on cellulose, compared to glucose. Proteomics on the secreted proteins in the growth medium confirmed this. A promoter analysis revealed the shortest active promoters for these two genes, as well as putative transcription factor binding sites.

  17. Comparative Genomics of Bacteriophage of the Genus Seuratvirus

    DEFF Research Database (Denmark)

    Sazinas, Pavelas; Redgwell, Tamsin; Rihtman, Branko

    2017-01-01

    Despite being more abundant and having smaller genomes than their bacterial host, relatively few bacteriophages have had their genomes sequenced. Here, we isolated 14 bacteriophages from cattle slurry and performed de novo genome sequencing, assembly, and annotation. The commonly used marker genes...... polB and terL showed these bacteriophages to be closely related to members of the genus Seuratvirus. We performed a core-gene analysis using the 14 new and four closely related genomes. A total of 58 core genes were identified, the majority of which has no known function. These genes were used...... to construct a core-gene phylogeny, the results of which confirmed the new isolates to be part of the genus Seuratvirus and expanded the number of species within this genus to four. All bacteriophages within the genus contained the genes queCDE encoding enzymes involved in queuosine biosynthesis. We suggest...

  18. Genomic signature and toxicogenomics comparison of polycationic gene delivery nanosystems in human alveolar epithelial A549 cells

    Directory of Open Access Journals (Sweden)

    J Barar

    2009-10-01

    Full Text Available "nBackground and the purpose of the study: Of the gene delivery systems, non-viral polycationic gene delivery nanosystems have been alternatively exploited as a relatively safe delivery reagents compared to viral vectors. However, little is known about the genomic impacts of these delivery systems in target cells/tissues. In this study, the toxicogenomics and genotoxicity potential of some selected polycationic lipid/polymer based nanostructures (i.e., Oligofectamine® (OF, starburst polyamidoamine Polyfect® (PF and diaminobutane (DAB dendrimers were investigated in human alveolar epithelial A549 cells. "nMethods: To study the nature and the ontology of the gene expression changes in A549 cells upon treatment with polycationic nanostructures, MTT assay and microarray gene expression profiling methodology were employed. For microarray analysis, cyanine (Cy3/Cy5 labeled cDNA samples from treated and untreated cells were hybridized on target arrays housing 200 genes. "nResults and major conclusions: The polycationic nanosystems induced significant gene expression changes belonging to different genomic ontologies such as cell defence and apoptosis pathways. These data suggest that polycationic nanosystems can elicit multiple gene expression changes in A549 cells upon their chemical structures and interactions with cellular/subcellular components. Such impacts may interfere with the main goals of the desired genemedicine.

  19. Comparative Genomics of Symbiotic Bacteria in Earthworm Nephridia

    DEFF Research Database (Denmark)

    Kjeldsen, Kasper Urup; Pinel, Nicolas; Lund, Marie Braad

    The excretory and osmoregulatory organs (nephridia) of lumbricid earthworms are densely colonized by extracellular bacterial symbionts belonging to the newly established betaproteobacterial genus Verminephrobacter. The nephridial symbiont of the earthworm Eisenia fetida was subjected to full genome...... sequencing along with two of its closest relatives; the plant pathogenic Acidovorax avena subsp. citrulli and the free-living Acidovorax sp. JS42. In addition, the genome of the nephridial symbiont of the earthworm Aporrectodea tuberculata was partially sequenced. In order to resolve the functional...

  20. A Guide to the PLAZA 3.0 Plant Comparative Genomic Database.

    Science.gov (United States)

    Vandepoele, Klaas

    2017-01-01

    PLAZA 3.0 is an online resource for comparative genomics and offers a versatile platform to study gene functions and gene families or to analyze genome organization and evolution in the green plant lineage. Starting from genome sequence information for over 35 plant species, precomputed comparative genomic data sets cover homologous gene families, multiple sequence alignments, phylogenetic trees, and genomic colinearity information within and between species. Complementary functional data sets, a Workbench, and interactive visualization tools are available through a user-friendly web interface, making PLAZA an excellent starting point to translate sequence or omics data sets into biological knowledge. PLAZA is available at http://bioinformatics.psb.ugent.be/plaza/ .

  1. DeltaProt: a software toolbox for comparative genomics

    Directory of Open Access Journals (Sweden)

    Willassen Nils P

    2010-11-01

    Full Text Available Abstract Background Statistical bioinformatics is the study of biological data sets obtained by new micro-technologies by means of proper statistical methods. For a better understanding of environmental adaptations of proteins, orthologous sequences from different habitats may be explored and compared. The main goal of the DeltaProt Toolbox is to provide users with important functionality that is needed for comparative screening and studies of extremophile proteins and protein classes. Visualization of the data sets is also the focus of this article, since visualizations can play a key role in making the various relationships transparent. This application paper is intended to inform the reader of the existence, functionality, and applicability of the toolbox. Results We present the DeltaProt Toolbox, a software toolbox that may be useful in importing, analyzing and visualizing data from multiple alignments of proteins. The toolbox has been written in MATLAB™ to provide an easy and user-friendly platform, including a graphical user interface, while ensuring good numerical performance. Problems in genome biology may be easily stated thanks to a compact input format. The toolbox also offers the possibility of utilizing structural information from the SABLE or other structure predictors. Different sequence plots can then be viewed and compared in order to find their similarities and differences. Detailed statistics are also calculated during the procedure. Conclusions The DeltaProt package is open source and freely available for academic, non-commercial use. The latest version of DeltaProt can be obtained from http://services.cbu.uib.no/software/deltaprot/. The website also contains documentation, and the toolbox comes with real data sets that are intended for training in applying the models to carry out bioinformatical and statistical analyses of protein sequences. Equipped with the new algorithms proposed here, DeltaProt serves as an auxiliary

  2. Microbial comparative pan-genomics using binomial mixture models

    Directory of Open Access Journals (Sweden)

    Ussery David W

    2009-08-01

    Full Text Available Abstract Background The size of the core- and pan-genome of bacterial species is a topic of increasing interest due to the growing number of sequenced prokaryote genomes, many from the same species. Attempts to estimate these quantities have been made, using regression methods or mixture models. We extend the latter approach by using statistical ideas developed for capture-recapture problems in ecology and epidemiology. Results We estimate core- and pan-genome sizes for 16 different bacterial species. The results reveal a complex dependency structure for most species, manifested as heterogeneous detection probabilities. Estimated pan-genome sizes range from small (around 2600 gene families in Buchnera aphidicola to large (around 43000 gene families in Escherichia coli. Results for Echerichia coli show that as more data become available, a larger diversity is estimated, indicating an extensive pool of rarely occurring genes in the population. Conclusion Analyzing pan-genomics data with binomial mixture models is a way to handle dependencies between genomes, which we find is always present. A bottleneck in the estimation procedure is the annotation of rarely occurring genes.

  3. Genomes of extremophile crucifers: new platforms for comparative genomics and beyond.

    Science.gov (United States)

    Dittami, Simon M; Tonon, Thierry

    2012-08-16

    Recent reports describe the genome sequencing of Thellungiella salsuginea and Thellungiella parvula, two extremophile crucifers closely related to the stress-sensitive model plant Arabidopsis thaliana.

  4. Intronic alternative splicing regulators identified by comparative genomics in nematodes.

    Directory of Open Access Journals (Sweden)

    Jennifer L Kabat

    2006-07-01

    Full Text Available Many alternative splicing events are regulated by pentameric and hexameric intronic sequences that serve as binding sites for splicing regulatory factors. We hypothesized that intronic elements that regulate alternative splicing are under selective pressure for evolutionary conservation. Using a Wobble Aware Bulk Aligner genomic alignment of Caenorhabditis elegans and Caenorhabditis briggsae, we identified 147 alternatively spliced cassette exons that exhibit short regions of high nucleotide conservation in the introns flanking the alternative exon. In vivo experiments on the alternatively spliced let-2 gene confirm that these conserved regions can be important for alternative splicing regulation. Conserved intronic element sequences were collected into a dataset and the occurrence of each pentamer and hexamer motif was counted. We compared the frequency of pentamers and hexamers in the conserved intronic elements to a dataset of all C. elegans intron sequences in order to identify short intronic motifs that are more likely to be associated with alternative splicing. High-scoring motifs were examined for upstream or downstream preferences in introns surrounding alternative exons. Many of the high-scoring nematode pentamer and hexamer motifs correspond to known mammalian splicing regulatory sequences, such as (TGCATG, indicating that the mechanism of alternative splicing regulation is well conserved in metazoans. A comparison of the analysis of the conserved intronic elements, and analysis of the entire introns flanking these same exons, reveals that focusing on intronic conservation can increase the sensitivity of detecting putative splicing regulatory motifs. This approach also identified novel sequences whose role in splicing is under investigation and has allowed us to take a step forward in defining a catalog of splicing regulatory elements for an organism. In vivo experiments confirm that one novel high-scoring sequence from our analysis

  5. Genome-wide comparative analysis of the IQD gene families in Arabidopsis thaliana and Oryza sativa

    Science.gov (United States)

    Abel, Steffen; Savchenko, Tatyana; Levy, Maggie

    2005-01-01

    Background Calcium signaling plays a prominent role in plants for coordinating a wide range of developmental processes and responses to environmental cues. Stimulus-specific generation of intracellular calcium transients, decoding of calcium signatures, and transformation of the signal into cellular responses are integral modules of the transduction process. Several hundred proteins with functions in calcium signaling circuits have been identified, and the number of downstream targets of calcium sensors is expected to increase. We previously identified a novel, calmodulin-binding nuclear protein, IQD1, which stimulates glucosinolate accumulation and plant defense in Arabidopsis thaliana. Here, we present a comparative genome-wide analysis of a new class of putative calmodulin target proteins in Arabidopsis and rice. Results We identified and analyzed 33 and 29 IQD1-like genes in Arabidopsis thaliana and Oryza sativa, respectively. The encoded IQD proteins contain a plant-specific domain of 67 conserved amino acid residues, referred to as the IQ67 domain, which is characterized by a unique and repetitive arrangement of three different calmodulin recruitment motifs, known as the IQ, 1-5-10, and 1-8-14 motifs. We demonstrated calmodulin binding for IQD20, the smallest IQD protein in Arabidopsis, which consists of a C-terminal IQ67 domain and a short N-terminal extension. A striking feature of IQD proteins is the high isoelectric point (~10.3) and frequency of serine residues (~11%). We compared the Arabidopsis and rice IQD gene families in terms of gene structure, chromosome location, predicted protein properties and motifs, phylogenetic relationships, and evolutionary history. The existence of an IQD-like gene in bryophytes suggests that IQD proteins are an ancient family of calmodulin-binding proteins and arose during the early evolution of land plants. Conclusion Comparative phylogenetic analyses indicate that the major IQD gene lineages originated before the

  6. IMG 4 version of the integrated microbial genomes comparative analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Markowitz, Victor M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Chen, I-Min A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Palaniappan, Krishna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Chu, Ken [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Szeto, Ernest [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Pillay, Manoj [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Ratner, Anna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Huang, Jinghua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Woyke, Tanja [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Huntemann, Marcel [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Anderson, Iain [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Billis, Konstantinos [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Varghese, Neha [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Mavromatis, Konstantinos [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Pati, Amrita [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Ivanova, Natalia N. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Kyrpides, Nikos C. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program

    2013-10-27

    The Integrated Microbial Genomes (IMG) data warehouse integrates genomes from all three domains of life, as well as plasmids, viruses and genome fragments. IMG provides tools for analyzing and reviewing the structural and functional annotations of genomes in a comparative context. IMG’s data content and analytical capabilities have increased continuously since its first version released in 2005. Since the last report published in the 2012 NAR Database Issue, IMG’s annotation and data integration pipelines have evolved while new tools have been added for recording and analyzing single cell genomes, RNA Seq and biosynthetic cluster data. Finally, different IMG datamarts provide support for the analysis of publicly available genomes (IMG/W: http://img.jgi.doe.gov/w), expert review of genome annotations (IMG/ER: http://img.jgi.doe.gov/er) and teaching and training in the area of microbial genome analysis (IMG/EDU: http://img.jgi.doe.gov/edu).

  7. The eastern oyster genome: A resource for comparative genomics in shellfish aquaculture species

    Science.gov (United States)

    Oyster aquaculture is an important sector of world food production. As such, it is imperative to develop a high quality reference genome for the eastern oyster, Crassostrea virginica, to assist in the elucidation of the genomic basis of commercially important traits. All genetic, gene expression and...

  8. Natural Product Biosynthetic Diversity and Comparative Genomics of the Cyanobacteria.

    Science.gov (United States)

    Dittmann, Elke; Gugger, Muriel; Sivonen, Kaarina; Fewer, David P

    2015-10-01

    Cyanobacteria are an ancient lineage of slow-growing photosynthetic bacteria and a prolific source of natural products with intricate chemical structures and potent biological activities. The bulk of these natural products are known from just a handful of genera. Recent efforts have elucidated the mechanisms underpinning the biosynthesis of a diverse array of natural products from cyanobacteria. Many of the biosynthetic mechanisms are unique to cyanobacteria or rarely described from other organisms. Advances in genome sequence technology have precipitated a deluge of genome sequences for cyanobacteria. This makes it possible to link known natural products to biosynthetic gene clusters but also accelerates the discovery of new natural products through genome mining. These studies demonstrate that cyanobacteria encode a huge variety of cryptic gene clusters for the production of natural products, and the known chemical diversity is likely to be just a fraction of the true biosynthetic capabilities of this fascinating and ancient group of organisms. Copyright © 2015. Published by Elsevier Ltd.

  9. Comparative Genomics of Vibrio cholerae from Haiti, Asia, and Africa

    Science.gov (United States)

    Reimer, Aleisha R.; Van Domselaar, Gary; Stroika, Steven; Walker, Matthew; Kent, Heather; Tarr, Cheryl; Talkington, Deborah; Rowe, Lori; Olsen-Rasmussen, Melissa; Frace, Michael; Sammons, Scott; Dahourou, Georges Anicet; Boncy, Jacques; Smith, Anthony M.; Mabon, Philip; Petkau, Aaron; Graham, Morag; Gilmour, Matthew W.

    2011-01-01

    Cholera was absent from the island of Hispaniola at least a century before an outbreak that began in Haiti in the fall of 2010. Pulsed-field gel electrophoresis (PFGE) analysis of clinical isolates from the Haiti outbreak and recent global travelers returning to the United States showed indistinguishable PFGE fingerprints. To better explore the genetic ancestry of the Haiti outbreak strain, we acquired 23 whole-genome Vibrio cholerae sequences: 9 isolates obtained in Haiti or the Dominican Republic, 12 PFGE pattern-matched isolates linked to Asia or Africa, and 2 nonmatched outliers from the Western Hemisphere. Phylogenies for whole-genome sequences and core genome single-nucleotide polymorphisms showed that the Haiti outbreak strain is genetically related to strains originating in India and Cameroon. However, because no identical genetic match was found among sequenced contemporary isolates, a definitive genetic origin for the outbreak in Haiti remains speculative. PMID:22099115

  10. Integrative and comparative genomics analysis of early hepatocellular carcinoma differentiated from liver regeneration in young and old

    Directory of Open Access Journals (Sweden)

    Ozand Pinar T

    2010-06-01

    Full Text Available Abstract Background Hepatocellular carcinoma (HCC is the third-leading cause of cancer-related deaths worldwide. It is often diagnosed at an advanced stage, and hence typically has a poor prognosis. To identify distinct molecular mechanisms for early HCC we developed a rat model of liver regeneration post-hepatectomy, as well as liver cells undergoing malignant transformation and compared them to normal liver using a microarray approach. Subsequently, we performed cross-species comparative analysis coupled with copy number alterations (CNA of independent early human HCC microarray studies to facilitate the identification of critical regulatory modules conserved across species. Results We identified 35 signature genes conserved across species, and shared among different types of early human HCCs. Over 70% of signature genes were cancer-related, and more than 50% of the conserved genes were mapped to human genomic CNA regions. Functional annotation revealed genes already implicated in HCC, as well as novel genes which were not previously reported in liver tumors. A subset of differentially expressed genes was validated using quantitative RT-PCR. Concordance was also confirmed for a significant number of genes and pathways in five independent validation microarray datasets. Our results indicated alterations in a number of cancer related pathways, including p53, p38 MAPK, ERK/MAPK, PI3K/AKT, and TGF-β signaling pathways, and potential critical regulatory role of MYC, ERBB2, HNF4A, and SMAD3 for early HCC transformation. Conclusions The integrative analysis of transcriptional deregulation, genomic CNA and comparative cross species analysis brings new insights into the molecular profile of early hepatoma formation. This approach may lead to robust biomarkers for the detection of early human HCC.

  11. Genus-Wide Comparative Genomics of Malassezia Delineates Its Phylogeny, Physiology, and Niche Adaptation on Human Skin.

    Directory of Open Access Journals (Sweden)

    Guangxi Wu

    2015-11-01

    Full Text Available Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64 with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741 were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin's carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin.

  12. Genus-Wide Comparative Genomics of Malassezia Delineates Its Phylogeny, Physiology, and Niche Adaptation on Human Skin.

    Science.gov (United States)

    Wu, Guangxi; Zhao, He; Li, Chenhao; Rajapakse, Menaka Priyadarsani; Wong, Wing Cheong; Xu, Jun; Saunders, Charles W; Reeder, Nancy L; Reilman, Raymond A; Scheynius, Annika; Sun, Sheng; Billmyre, Blake Robert; Li, Wenjun; Averette, Anna Floyd; Mieczkowski, Piotr; Heitman, Joseph; Theelen, Bart; Schröder, Markus S; De Sessions, Paola Florez; Butler, Geraldine; Maurer-Stroh, Sebastian; Boekhout, Teun; Nagarajan, Niranjan; Dawson, Thomas L

    2015-11-01

    Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi) that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64) with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741) were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin's carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin.

  13. Systematic CpT (ApG) Depletion and CpG Excess Are Unique Genomic Signatures of Large DNA Viruses Infecting Invertebrates

    Science.gov (United States)

    Upadhyay, Mohita; Sharma, Neha; Vivekanandan, Perumal

    2014-01-01

    Differences in the relative abundance of dinucleotides, if any may provide important clues on host-driven evolution of viruses. We studied dinucleotide frequencies of large DNA viruses infecting vertebrates (n = 105; viruses infecting mammals = 99; viruses infecting aves = 6; viruses infecting reptiles = 1) and invertebrates (n = 88; viruses infecting insects = 84; viruses infecting crustaceans = 4). We have identified systematic depletion of CpT(ApG) dinucleotides and over-representation of CpG dinucleotides as the unique genomic signature of large DNA viruses infecting invertebrates. Detailed investigation of this unique genomic signature suggests the existence of invertebrate host-induced pressures specifically targeting CpT(ApG) and CpG dinucleotides. The depletion of CpT dinucleotides among large DNA viruses infecting invertebrates is at least in part, explained by non-canonical DNA methylation by the infected host. Our findings highlight the role of invertebrate host-related factors in shaping virus evolution and they also provide the necessary framework for future studies on evolution, epigenetics and molecular biology of viruses infecting this group of hosts. PMID:25369195

  14. The Complete Chloroplast Genome of Catha edulis: A Comparative Analysis of Genome Features with Related Species

    Directory of Open Access Journals (Sweden)

    Cuihua Gu

    2018-02-01

    Full Text Available Qat (Catha edulis, Celastraceae is a woody evergreen species with great economic and cultural importance. It is cultivated for its stimulant alkaloids cathine and cathinone in East Africa and southwest Arabia. However, genome information, especially DNA sequence resources, for C. edulis are limited, hindering studies regarding interspecific and intraspecific relationships. Herein, the complete chloroplast (cp genome of Catha edulis is reported. This genome is 157,960 bp in length with 37% GC content and is structurally arranged into two 26,577 bp inverted repeats and two single-copy areas. The size of the small single-copy and the large single-copy regions were 18,491 bp and 86,315 bp, respectively. The C. edulis cp genome consists of 129 coding genes including 37 transfer RNA (tRNA genes, 8 ribosomal RNA (rRNA genes, and 84 protein coding genes. For those genes, 112 are single copy genes and 17 genes are duplicated in two inverted regions with seven tRNAs, four rRNAs, and six protein coding genes. The phylogenetic relationships resolved from the cp genome of qat and 32 other species confirms the monophyly of Celastraceae. The cp genomes of C. edulis, Euonymus japonicus and seven Celastraceae species lack the rps16 intron, which indicates an intron loss took place among an ancestor of this family. The cp genome of C. edulis provides a highly valuable genetic resource for further phylogenomic research, barcoding and cp transformation in Celastraceae.

  15. Genome sequences and comparative genomics of two Lactobacillus ruminis strains from the bovine and human intestinal tracts

    LENUS (Irish Health Repository)

    2011-08-30

    Abstract Background The genus Lactobacillus is characterized by an extraordinary degree of phenotypic and genotypic diversity, which recent genomic analyses have further highlighted. However, the choice of species for sequencing has been non-random and unequal in distribution, with only a single representative genome from the L. salivarius clade available to date. Furthermore, there is no data to facilitate a functional genomic analysis of motility in the lactobacilli, a trait that is restricted to the L. salivarius clade. Results The 2.06 Mb genome of the bovine isolate Lactobacillus ruminis ATCC 27782 comprises a single circular chromosome, and has a G+C content of 44.4%. In silico analysis identified 1901 coding sequences, including genes for a pediocin-like bacteriocin, a single large exopolysaccharide-related cluster, two sortase enzymes, two CRISPR loci and numerous IS elements and pseudogenes. A cluster of genes related to a putative pilin was identified, and shown to be transcribed in vitro. A high quality draft assembly of the genome of a second L. ruminis strain, ATCC 25644 isolated from humans, suggested a slightly larger genome of 2.138 Mb, that exhibited a high degree of synteny with the ATCC 27782 genome. In contrast, comparative analysis of L. ruminis and L. salivarius identified a lack of long-range synteny between these closely related species. Comparison of the L. salivarius clade core proteins with those of nine other Lactobacillus species distributed across 4 major phylogenetic groups identified the set of shared proteins, and proteins unique to each group. Conclusions The genome of L. ruminis provides a comparative tool for directing functional analyses of other members of the L. salivarius clade, and it increases understanding of the divergence of this distinct Lactobacillus lineage from other commensal lactobacilli. The genome sequence provides a definitive resource to facilitate investigation of the genetics, biochemistry and host

  16. Identification of W chromosomes in Lepidoptera by comparative genome hybridization

    Czech Academy of Sciences Publication Activity Database

    Sahara, K.; Marec, František; Traut, W.

    1998-01-01

    Roč. 98, č. 6 (1998), s. 20 [International Symposium on Genomics and Proteomics - Functional and Computational Aspects and Annual Meeting of the GfG. 04.10.1998-07.10.1998, Heidelberg] Keywords : Galleria mellonella * DNA Subject RIV: EB - Genetics ; Molecular Biology

  17. Comparative genomics of toxigenic and non-toxigenic Staphylococcus hyicus

    DEFF Research Database (Denmark)

    Leekitcharoenphon, Pimlapas; Pamp, Sünje Johanna; Andresen, Lars Ole

    2016-01-01

    The most common causative agent of exudative epidermitis (EE) in pigs is Staphylococcus hyicus. S. hyicus can be grouped into toxigenic and non-toxigenic strains based on their ability to cause EE in pigs and specific virulence genes have been identified. A genome wide comparison between non...

  18. Comparative genomic and phylogenomic analyses of the Bifidobacteriaceae family

    Czech Academy of Sciences Publication Activity Database

    Lugli, G. A.; Milani, C.; Turroni, F.; Duranti, S.; Mancabelli, L.; Mangifesta, M.; Ferrario, C.; Modesto, M.; Mattarelli, P.; Killer, Jiří; van Sinderen, D.

    2017-01-01

    Roč. 18, č. 1 (2017), č. článku 568. ISSN 1471-2164 Institutional support: RVO:67985904 Keywords : Bifidobacteriaceae * genomics * phlogenomics Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.729, year: 2016

  19. Genomic Comparative Study of Bovine Mastitis Escherichia coli.

    Science.gov (United States)

    Kempf, Florent; Slugocki, Cindy; Blum, Shlomo E; Leitner, Gabriel; Germon, Pierre

    2016-01-01

    Escherichia coli, one of the main causative agents of bovine mastitis, is responsible for significant losses on dairy farms. In order to better understand the pathogenicity of E. coli mastitis, an accurate characterization of E. coli strains isolated from mastitis cases is required. By using phylogenetic analyses and whole genome comparison of 5 currently available mastitis E. coli genome sequences, we searched for genotypic traits specific for mastitis isolates. Our data confirm that there is a bias in the distribution of mastitis isolates in the different phylogenetic groups of the E. coli species, with the majority of strains belonging to phylogenetic groups A and B1. An interesting feature is that clustering of strains based on their accessory genome is very similar to that obtained using the core genome. This finding illustrates the fact that phenotypic properties of strains from different phylogroups are likely to be different. As a consequence, it is possible that different strategies could be used by mastitis isolates of different phylogroups to trigger mastitis. Our results indicate that mastitis E. coli isolates analyzed in this study carry very few of the virulence genes described in other pathogenic E. coli strains. A more detailed analysis of the presence/absence of genes involved in LPS synthesis, iron acquisition and type 6 secretion systems did not uncover specific properties of mastitis isolates. Altogether, these results indicate that mastitis E. coli isolates are rather characterized by a lack of bona fide currently described virulence genes.

  20. Cloud computing for comparative genomics with windows azure platform.

    Science.gov (United States)

    Kim, Insik; Jung, Jae-Yoon; Deluca, Todd F; Nelson, Tristan H; Wall, Dennis P

    2012-01-01

    Cloud computing services have emerged as a cost-effective alternative for cluster systems as the number of genomes and required computation power to analyze them increased in recent years. Here we introduce the Microsoft Azure platform with detailed execution steps and a cost comparison with Amazon Web Services.

  1. Genomic Comparative Study of Bovine Mastitis Escherichia coli

    Science.gov (United States)

    Kempf, Florent; Slugocki, Cindy; Blum, Shlomo E.; Leitner, Gabriel; Germon, Pierre

    2016-01-01

    Escherichia coli, one of the main causative agents of bovine mastitis, is responsible for significant losses on dairy farms. In order to better understand the pathogenicity of E. coli mastitis, an accurate characterization of E. coli strains isolated from mastitis cases is required. By using phylogenetic analyses and whole genome comparison of 5 currently available mastitis E. coli genome sequences, we searched for genotypic traits specific for mastitis isolates. Our data confirm that there is a bias in the distribution of mastitis isolates in the different phylogenetic groups of the E. coli species, with the majority of strains belonging to phylogenetic groups A and B1. An interesting feature is that clustering of strains based on their accessory genome is very similar to that obtained using the core genome. This finding illustrates the fact that phenotypic properties of strains from different phylogroups are likely to be different. As a consequence, it is possible that different strategies could be used by mastitis isolates of different phylogroups to trigger mastitis. Our results indicate that mastitis E. coli isolates analyzed in this study carry very few of the virulence genes described in other pathogenic E. coli strains. A more detailed analysis of the presence/absence of genes involved in LPS synthesis, iron acquisition and type 6 secretion systems did not uncover specific properties of mastitis isolates. Altogether, these results indicate that mastitis E. coli isolates are rather characterized by a lack of bona fide currently described virulence genes. PMID:26809117

  2. Comparative and functional genomics of lipases in holometabolous insects.

    Science.gov (United States)

    Horne, Irene; Haritos, Victoria S; Oakeshott, John G

    2009-08-01

    Lipases have key roles in insect lipid acquisition, storage and mobilisation and are also fundamental to many physiological processes underpinning insect reproduction, development, defence from pathogens and oxidative stress, and pheromone signalling. We have screened the recently sequenced genomes of five species from four orders of holometabolous insects, the dipterans Drosophila melanogaster and Anopheles gambiae, the hymenopteran Apis mellifera, the moth Bombyx mori and the beetle Tribolium castaneum, for the six major lipase families that are also found in other organisms. The two most numerous families in the insects, the neutral and acid lipases, are also the main families in mammals, albeit not in Caenorhabditis elegans, plants or microbes. Total numbers of the lipases vary two-fold across the five insect species, from numbers similar to those in mammals up to numbers comparable to those seen in C. elegans. Whilst there is a high degree of orthology with mammalian lipases in the other four families, the great majority of the insect neutral and acid lipases have arisen since the insect orders themselves diverged. Intriguingly, about 10% of the insect neutral and acid lipases have lost motifs critical for catalytic function. Examination of the length of lid and loop regions of the neutral lipase sequences suggest that most of the insect lipases lack triacylglycerol (TAG) hydrolysis activity, although the acid lipases all have intact cap domains required for TAG hydrolysis. We have also reviewed the sequence databases and scientific literature for insights into the expression profiles and functions of the insect neutral and acid lipases and the orthologues of the mammalian adipose triglyceride lipase which has a pivotal role in lipid mobilisation. These data suggest that some of the acid and neutral lipase diversity may be due to a requirement for rapid accumulation of dietary lipids. The different roles required of lipases at the four discrete life stages of

  3. Mitochondrial genome sequences and comparative genomics ofPhytophthora ramorum and P. sojae

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Frank N.; Douda, Bensasson; Tyler, Brett M.; Boore,Jeffrey L.

    2007-01-01

    The complete sequences of the mitochondrial genomes of theoomycetes of Phytophthora ramorum and P. sojae were determined during thecourse of their complete nuclear genome sequencing (Tyler, et al. 2006).Both are circular, with sizes of 39,314 bp for P. ramorum and 42,975 bpfor P. sojae. Each contains a total of 37 identifiable protein-encodinggenes, 25 or 26 tRNAs (P. sojae and P. ramorum, respectively)specifying19 amino acids, and a variable number of ORFs (7 for P. ramorum and 12for P. sojae) which are potentially additional functional genes.Non-coding regions comprise approximately 11.5 percent and 18.4 percentof the genomes of P. ramorum and P. sojae, respectively. Relative to P.sojae, there is an inverted repeat of 1,150 bp in P. ramorum thatincludes an unassigned unique ORF, a tRNA gene, and adjacent non-codingsequences, but otherwise the gene order in both species is identical.Comparisons of these genomes with published sequences of the P. infestansmitochondrial genome reveals a number of similarities, but the gene orderin P. infestans differs in two adjacent locations due to inversions.Sequence alignments of the three genomes indicated sequence conservationranging from 75 to 85 percent and that specific regions were morevariable than others.

  4. Comparative genomics in chicken and Pekin duck using FISH mapping and microarray analysis

    Directory of Open Access Journals (Sweden)

    Fowler Katie E

    2009-08-01

    Full Text Available Abstract Background The availability of the complete chicken (Gallus gallus genome sequence as well as a large number of chicken probes for fluorescent in-situ hybridization (FISH and microarray resources facilitate comparative genomic studies between chicken and other bird species. In a previous study, we provided a comprehensive cytogenetic map for the turkey (Meleagris gallopavo and the first analysis of copy number variants (CNVs in birds. Here, we extend this approach to the Pekin duck (Anas platyrhynchos, an obvious target for comparative genomic studies due to its agricultural importance and resistance to avian flu. Results We provide a detailed molecular cytogenetic map of the duck genome through FISH assignment of 155 chicken clones. We identified one inter- and six intrachromosomal rearrangements between chicken and duck macrochromosomes and demonstrated conserved synteny among all microchromosomes analysed. Array comparative genomic hybridisation revealed 32 CNVs, of which 5 overlap previously designated "hotspot" regions between chicken and turkey. Conclusion Our results suggest extensive conservation of avian genomes across 90 million years of evolution in both macro- and microchromosomes. The data on CNVs between chicken and duck extends previous analyses in chicken and turkey and supports the hypotheses that avian genomes contain fewer CNVs than mammalian genomes and that genomes of evolutionarily distant species share regions of copy number variation ("CNV hotspots". Our results will expedite duck genomics, assist marker development and highlight areas of interest for future evolutionary and functional studies.

  5. Comparative Genomics Analysis of Streptomyces Species Reveals Their Adaptation to the Marine Environment and Their Diversity at the Genomic Level

    Science.gov (United States)

    Tian, Xinpeng; Zhang, Zhewen; Yang, Tingting; Chen, Meili; Li, Jie; Chen, Fei; Yang, Jin; Li, Wenjie; Zhang, Bing; Zhang, Zhang; Wu, Jiayan; Zhang, Changsheng; Long, Lijuan; Xiao, Jingfa

    2016-01-01

    Over 200 genomes of streptomycete strains that were isolated from various environments are available from the NCBI. However, little is known about the characteristics that are linked to marine adaptation in marine-derived streptomycetes. The particularity and complexity of the marine environment suggest that marine streptomycetes are genetically diverse. Here, we sequenced nine strains from the Streptomyces genus that were isolated from different longitudes, latitudes, and depths of the South China Sea. Then we compared these strains to 22 NCBI downloaded streptomycete strains. Thirty-one streptomycete strains are clearly grouped into a marine-derived subgroup and multiple source subgroup-based phylogenetic tree. The phylogenetic analyses have revealed the dynamic process underlying streptomycete genome evolution, and lateral gene transfer is an important driving force during the process. Pan-genomics analyses have revealed that streptomycetes have an open pan-genome, which reflects the diversity of these streptomycetes and guarantees the species a quick and economical response to diverse environments. Functional and comparative genomics analyses indicate that the marine-derived streptomycetes subgroup possesses some common characteristics of marine adaptation. Our findings have expanded our knowledge of how ocean isolates of streptomycete strains adapt to marine environments. The availability of streptomycete genomes from the South China Sea will be beneficial for further analysis on marine streptomycetes and will enrich the South China Sea’s genetic data sources. PMID:27446038

  6. Genomic features, phylogenetic relationships, and comparative genomics of Elizabethkingia anophelis strain EM361-97 isolated in Taiwan.

    Science.gov (United States)

    Lin, Jiun-Nong; Lai, Chung-Hsu; Yang, Chih-Hui; Huang, Yi-Han; Lin, Hsi-Hsun

    2017-10-30

    Elizabethkingia anophelis has become an emerging infection in humans. Recent research has shown that previous reports of E. meningoseptica infections might in fact be caused by E. anophelis. We aimed to investigate the genomic features, phylogenetic relationships, and comparative genomics of this emerging pathogen. Elizabethkingia anophelis strain EM361-97 was isolated from the blood of a cancer patient in Taiwan. The total length of the draft genome was 4,084,052 bp. The whole-genome analysis identified the presence of a number of antibiotic resistance genes, which corresponded with the antibiotic susceptibility phenotype of this strain. Based on the average nucleotide identity, the phylogenetic analysis revealed that E. anophelis EM361-97 was a sister group to E. anophelis FMS-007, which was isolated from a patient with T-cell non-Hodgkin's lymphoma in China. Knowledge of the genomic characteristics and comparative genomics of E. anophelis will provide researchers and clinicians with important information to understand this emerging microorganism.

  7. Comparative genomics of extrachromosomal elements in Bacillus thuringiensis subsp. israelensis.

    Science.gov (United States)

    Bolotin, Alexandre; Gillis, Annika; Sanchis, Vincent; Nielsen-LeRoux, Christina; Mahillon, Jacques; Lereclus, Didier; Sorokin, Alexei

    2017-05-01

    Bacillus thuringiensis subsp. israelensis is one of the most important microorganisms used against mosquitoes. It was intensively studied following its discovery and became a model bacterium of the B. thuringiensis species. Those studies focused on toxin genes, aggregation-associated conjugation, linear genome phages, etc. Recent announcements of genomic sequences of different strains have not been explicitly related to the biological properties studied. We report data on plasmid content analysis of four strains using ultra-high-throughput sequencing. The strains were commercial product isolates, with their putative ancestor and type B. thuringiensis subsp. israelensis strain sequenced earlier. The assembled contigs corresponding to published and novel data were assigned to plasmids described earlier in B. thuringiensis subsp. israelensis and other B. thuringiensis strains. A new 360 kb plasmid was identified, encoding multiple transporters, also found in most of the earlier sequenced strains. Our genomic data show the presence of two toxin-coding plasmids of 128 and 100 kb instead of the reported 225 kb plasmid, a co-integrate of the former two. In two of the sequenced strains, only a 100 kb plasmid was present. Some heterogeneity exists in the small plasmid content and structure between strains. These data support the perception of active plasmid exchange among B. thuringiensis subsp. israelensis strains in nature. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  8. Complete genome sequence of Borrelia afzelii K78 and comparative genome analysis.

    Directory of Open Access Journals (Sweden)

    Wolfgang Schüler

    Full Text Available The main Borrelia species causing Lyme borreliosis in Europe and Asia are Borrelia afzelii, B. garinii, B. burgdorferi and B. bavariensis. This is in contrast to the United States, where infections are exclusively caused by B. burgdorferi. Until to date the genome sequences of four B. afzelii strains, of which only two include the numerous plasmids, are available. In order to further assess the genetic diversity of B. afzelii, the most common species in Europe, responsible for the large variety of clinical manifestations of Lyme borreliosis, we have determined the full genome sequence of the B. afzelii strain K78, a clinical isolate from Austria. The K78 genome contains a linear chromosome (905,949 bp and 13 plasmids (8 linear and 5 circular together presenting 1,309 open reading frames of which 496 are located on plasmids. With the exception of lp28-8, all linear replicons in their full length including their telomeres have been sequenced. The comparison with the genomes of the four other B. afzelii strains, ACA-1, PKo, HLJ01 and Tom3107, as well as the one of B. burgdorferi strain B31, confirmed a high degree of conservation within the linear chromosome of B. afzelii, whereas plasmid encoded genes showed a much larger diversity. Since some plasmids present in B. burgdorferi are missing in the B. afzelii genomes, the corresponding virulence factors of B. burgdorferi are found in B. afzelii on other unrelated plasmids. In addition, we have identified a species specific region in the circular plasmid, cp26, which could be used for species determination. Different non-coding RNAs have been located on the B. afzelii K78 genome, which have not previously been annotated in any of the published Borrelia genomes.

  9. Complete Genome Sequence of Borrelia afzelii K78 and Comparative Genome Analysis

    Science.gov (United States)

    Schüler, Wolfgang; Bunikis, Ignas; Weber-Lehman, Jacqueline; Comstedt, Pär; Kutschan-Bunikis, Sabrina; Stanek, Gerold; Huber, Jutta; Meinke, Andreas; Bergström, Sven; Lundberg, Urban

    2015-01-01

    The main Borrelia species causing Lyme borreliosis in Europe and Asia are Borrelia afzelii, B. garinii, B. burgdorferi and B. bavariensis. This is in contrast to the United States, where infections are exclusively caused by B. burgdorferi. Until to date the genome sequences of four B. afzelii strains, of which only two include the numerous plasmids, are available. In order to further assess the genetic diversity of B. afzelii, the most common species in Europe, responsible for the large variety of clinical manifestations of Lyme borreliosis, we have determined the full genome sequence of the B. afzelii strain K78, a clinical isolate from Austria. The K78 genome contains a linear chromosome (905,949 bp) and 13 plasmids (8 linear and 5 circular) together presenting 1,309 open reading frames of which 496 are located on plasmids. With the exception of lp28-8, all linear replicons in their full length including their telomeres have been sequenced. The comparison with the genomes of the four other B. afzelii strains, ACA-1, PKo, HLJ01 and Tom3107, as well as the one of B. burgdorferi strain B31, confirmed a high degree of conservation within the linear chromosome of B. afzelii, whereas plasmid encoded genes showed a much larger diversity. Since some plasmids present in B. burgdorferi are missing in the B. afzelii genomes, the corresponding virulence factors of B. burgdorferi are found in B. afzelii on other unrelated plasmids. In addition, we have identified a species specific region in the circular plasmid, cp26, which could be used for species determination. Different non-coding RNAs have been located on the B. afzelii K78 genome, which have not previously been annotated in any of the published Borrelia genomes. PMID:25798594

  10. The Integrated Microbial Genomes (IMG) System: An Expanding Comparative Analysis Resource

    Energy Technology Data Exchange (ETDEWEB)

    Markowitz, Victor M.; Chen, I-Min A.; Palaniappan, Krishna; Chu, Ken; Szeto, Ernest; Grechkin, Yuri; Ratner, Anna; Anderson, Iain; Lykidis, Athanasios; Mavromatis, Konstantinos; Ivanova, Natalia N.; Kyrpides, Nikos C.

    2009-09-13

    The integrated microbial genomes (IMG) system serves as a community resource for comparative analysis of publicly available genomes in a comprehensive integrated context. IMG contains both draft and complete microbial genomes integrated with other publicly available genomes from all three domains of life, together with a large number of plasmids and viruses. IMG provides tools and viewers for analyzing and reviewing the annotations of genes and genomes in a comparative context. Since its first release in 2005, IMG's data content and analytical capabilities have been constantly expanded through regular releases. Several companion IMG systems have been set up in order to serve domain specific needs, such as expert review of genome annotations. IMG is available at .

  11. Genome wide characterization of simple sequence repeats in watermelon genome and their application in comparative mapping and genetic diversity analysis.

    Science.gov (United States)

    Zhu, Huayu; Song, Pengyao; Koo, Dal-Hoe; Guo, Luqin; Li, Yanman; Sun, Shouru; Weng, Yiqun; Yang, Luming

    2016-08-05

    Microsatellite markers are one of the most informative and versatile DNA-based markers used in plant genetic research, but their development has traditionally been difficult and costly. The whole genome sequencing with next-generation sequencing (NGS) technologies provides large amounts of sequence data to develop numerous microsatellite markers at whole genome scale. SSR markers have great advantage in cross-species comparisons and allow investigation of karyotype and genome evolution through highly efficient computation approaches such as in silico PCR. Here we described genome wide development and characterization of SSR markers in the watermelon (Citrullus lanatus) genome, which were then use in comparative analysis with two other important crop species in the Cucurbitaceae family: cucumber (Cucumis sativus L.) and melon (Cucumis melo L.). We further applied these markers in evaluating the genetic diversity and population structure in watermelon germplasm collections. A total of 39,523 microsatellite loci were identified from the watermelon draft genome with an overall density of 111 SSRs/Mbp, and 32,869 SSR primers were designed with suitable flanking sequences. The dinucleotide SSRs were the most common type representing 34.09 % of the total SSR loci and the AT-rich motifs were the most abundant in all nucleotide repeat types. In silico PCR analysis identified 832 and 925 SSR markers with each having a single amplicon in the cucumber and melon draft genome, respectively. Comparative analysis with these cross-species SSR markers revealed complicated mosaic patterns of syntenic blocks among the genomes of three species. In addition, genetic diversity analysis of 134 watermelon accessions with 32 highly informative SSR loci placed these lines into two groups with all accessions of C.lanatus var. citorides and three accessions of C. colocynthis clustered in one group and all accessions of C. lanatus var. lanatus and the remaining accessions of C. colocynthis

  12. Characterization of Streptococcus tigurinus small-colony variants causing prosthetic joint infection by comparative whole-genome analyses.

    Science.gov (United States)

    Zbinden, Andrea; Quiblier, Chantal; Hernandez, David; Herzog, Kathrin; Bodler, Paul; Senn, Maria M; Gizard, Yann; Schrenzel, Jacques; François, Patrice

    2014-02-01

    Small-colony variants (SCVs) of bacteria are associated with recurrent and persistent infections. We describe for the first time SCVs of Streptococcus tigurinus in a patient with a prosthetic joint infection. S. tigurinus is a novel pathogen of the Streptococcus mitis group and causes invasive infections. We sought to characterize S. tigurinus SCVs using experimental methods and find possible genetic explanations for their phenotypes. The S. tigurinus SCVs were compared with the wild-type (WT) isolate using phenotypic methods, including growth under different conditions, autolysis, and visualization of the cell ultrastructure by use of transmission electron microscopy (TEM). Furthermore, comparative genome analyses were performed. The S. tigurinus SCVs displayed reduced growth compared to the WT and showed either a very stable or a fluctuating SCV phenotype. TEM analyses revealed major alterations in cell separation and morphological abnormalities, which were partially explained by impaired autolytic behavior. Intriguingly, the SCVs were more resistant to induced autolysis. Whole-genome sequencing revealed mutations in the genes involved in general cell metabolism, cell division, stringent response, and virulence. Clinically, the patient recovered after a 2-stage exchange of the prosthesis. Comparative whole-genome sequencing in clinical strains is a useful tool for identifying novel genetic signatures leading to the most persistent bacterial forms. The detection of viridans streptococcal SCVs is challenging in a clinical laboratory due to the small colony size. Thus, it is of major clinical importance for microbiologists and clinicians to be aware of viridans streptococcal SCVs, such as those of S. tigurinus, which lead to difficult-to-treat infections.

  13. Tracking animal movement by comparing trace element signatures in claws to spatial variability of elements in soils.

    Science.gov (United States)

    Ethier, Danielle M; Kyle, Christopher J; Nocera, Joseph J

    2014-01-15

    Biogeochemical markers in ecology have provided a useful means for indicating geographic origin and movement patterns of species on various temporal and spatial scales. We used trace element analysis to resolve spatial and habitat-specific environmental gradients in elemental distributions that could be used to infer geographic origin and habitat association in a model terrestrial carnivore: American badger (Taxidea taxus jacksoni). To accomplish this, we generated element base-maps using spatial principal component analysis, and assessed habitat-specific signatures using multivariate statistics from soil element concentrations in southwestern Ontario, Canada. Using canonical correlation analysis (CCA) we also test whether element variability in the claw keratin of a terrestrial carnivore could be explained by the chemical variability in the soils of the local environment. Results demonstrated that trace element signatures in soils vary locally with land use practices and soil texture type and broadly with the underlying geology. CCA results suggest that chemical profiles in claws can be linked to the surrounding chemical environment, providing evidence that geographic patterns in mammalian movement can be discerned on the basis of claw chemistry. From this, we conclude that geographic assignment of individuals based on element profiles in their tissues and referenced against soil elemental distributions would be coarse (at a spatial scale of 100-1000 km, depending on the chemical heterogeneity of the landscape), but could be used to assess origin of highly mobile animals or habitat association of individuals. Compared to stable isotope analysis, the assessment of trace elements can provide a much greater level of detail in backcasting animal movement pathways. © 2013. Published by Elsevier B.V. All rights reserved.

  14. Genomic Signature of the Natural Oncolytic Herpes Simplex Virus HF10 and Its Therapeutic Role in Preclinical and Clinical Trials

    Directory of Open Access Journals (Sweden)

    Ibrahim Ragab Eissa

    2017-07-01

    Full Text Available Oncolytic viruses (OVs are opening new possibilities in cancer therapy with their unique mechanism of selective replication within tumor cells and triggering of antitumor immune responses. HF10 is an oncolytic herpes simplex virus-1 with a unique genomic structure that has non-engineered deletions and insertions accompanied by frame-shift mutations, in contrast to the majority of engineered OVs. At the genetic level, HF10 naturally lacks the expression of UL43, UL49.5, UL55, UL56, and latency-associated transcripts, and overexpresses UL53 and UL54. In preclinical studies, HF10 replicated efficiently within tumor cells with extensive cytolytic effects and induced increased numbers of activated CD4+ and CD8+ T cells and natural killer cells within the tumor, leading to a significant reduction in tumor growth and prolonged survival rates. Investigator-initiated clinical studies of HF10 have been completed in recurrent breast carcinoma, head and neck cancer, and unresectable pancreatic cancer in Japan. Phase I trials were subsequently completed in refractory superficial cancers and melanoma in the United States. HF10 has been demonstrated to have a high safety margin with low frequency of adverse effects in all treated patients. Interestingly, HF10 antigens were detected in pancreatic carcinoma over 300 days after treatment with infiltration of CD4+ and CD8+ T cells, which enhanced the immune response. To date, preliminary results from a Phase II trial have indicated that HF10 in combination with ipilimumab (anti-CTLA-4 is safe and well tolerated, with high antitumor efficacy. Improvement of the effect of ipilimumab was observed in patients with stage IIIb, IIIc, or IV unresectable or metastatic melanoma. This review provides a concise description of the genomic functional organization of HF10 compared with talimogene laherparepvec. Furthermore, this review focuses on HF10 in cancer treatment as monotherapy as well as in combination therapy

  15. Genome-wide analysis of signatures of selection in populations of African honey bees (Apis mellifera) using new web-based tools.

    Science.gov (United States)

    Fuller, Zachary L; Niño, Elina L; Patch, Harland M; Bedoya-Reina, Oscar C; Baumgarten, Tracey; Muli, Elliud; Mumoki, Fiona; Ratan, Aakrosh; McGraw, John; Frazier, Maryann; Masiga, Daniel; Schuster, Stephen; Grozinger, Christina M; Miller, Webb

    2015-07-10

    With the development of inexpensive, high-throughput sequencing technologies, it has become feasible to examine questions related to population genetics and molecular evolution of non-model species in their ecological contexts on a genome-wide scale. Here, we employed a newly developed suite of integrated, web-based programs to examine population dynamics and signatures of selection across the genome using several well-established tests, including F ST, pN/pS, and McDonald-Kreitman. We applied these techniques to study populations of honey bees (Apis mellifera) in East Africa. In Kenya, there are several described A. mellifera subspecies, which are thought to be localized to distinct ecological regions. We performed whole genome sequencing of 11 worker honey bees from apiaries distributed throughout Kenya and identified 3.6 million putative single-nucleotide polymorphisms. The dense coverage allowed us to apply several computational procedures to study population structure and the evolutionary relationships among the populations, and to detect signs of adaptive evolution across the genome. While there is considerable gene flow among the sampled populations, there are clear distinctions between populations from the northern desert region and those from the temperate, savannah region. We identified several genes showing population genetic patterns consistent with positive selection within African bee populations, and between these populations and European A. mellifera or Asian Apis florea. These results lay the groundwork for future studies of adaptive ecological evolution in honey bees, and demonstrate the use of new, freely available web-based tools and workflows ( http://usegalaxy.org/r/kenyanbee ) that can be applied to any model system with genomic information.

  16. Identification and analysis of genome-wide SNPs provide insight into signatures of selection and domestication in channel catfish (Ictalurus punctatus.

    Directory of Open Access Journals (Sweden)

    Luyang Sun

    Full Text Available Domestication and selection for important performance traits can impact the genome, which is most often reflected by reduced heterozygosity in and surrounding genes related to traits affected by selection. In this study, analysis of the genomic impact caused by domestication and artificial selection was conducted by investigating the signatures of selection using single nucleotide polymorphisms (SNPs in channel catfish (Ictalurus punctatus. A total of 8.4 million candidate SNPs were identified by using next generation sequencing. On average, the channel catfish genome harbors one SNP per 116 bp. Approximately 6.6 million, 5.3 million, 4.9 million, 7.1 million and 6.7 million SNPs were detected in the Marion, Thompson, USDA103, Hatchery strain, and wild population, respectively. The allele frequencies of 407,861 SNPs differed significantly between the domestic and wild populations. With these SNPs, 23 genomic regions with putative selective sweeps were identified that included 11 genes. Although the function for the majority of the genes remain unknown in catfish, several genes with known function related to aquaculture performance traits were included in the regions with selective sweeps. These included hypoxia-inducible factor 1β. HIFιβ.. and the transporter gene ATP-binding cassette sub-family B member 5 (ABCB5. HIF1β. is important for response to hypoxia and tolerance to low oxygen levels is a critical aquaculture trait. The large numbers of SNPs identified from this study are valuable for the development of high-density SNP arrays for genetic and genomic studies of performance traits in catfish.

  17. Phylogenomics and Comparative Genomic Studies Robustly Support Division of the Genus Mycobacterium into an Emended Genus Mycobacterium and Four Novel Genera

    Science.gov (United States)

    Gupta, Radhey S.; Lo, Brian; Son, Jeen

    2018-01-01

    The genus Mycobacterium contains 188 species including several major human pathogens as well as numerous other environmental species. We report here comprehensive phylogenomics and comparative genomic analyses on 150 genomes of Mycobacterium species to understand their interrelationships. Phylogenetic trees were constructed for the 150 species based on 1941 core proteins for the genus Mycobacterium, 136 core proteins for the phylum Actinobacteria and 8 other conserved proteins. Additionally, the overall genome similarity amongst the Mycobacterium species was determined based on average amino acid identity of the conserved protein families. The results from these analyses consistently support the existence of five distinct monophyletic groups within the genus Mycobacterium at the highest level, which are designated as the “Tuberculosis-Simiae,” “Terrae,” “Triviale,” “Fortuitum-Vaccae,” and “Abscessus-Chelonae” clades. Some of these clades have also been observed in earlier phylogenetic studies. Of these clades, the “Abscessus-Chelonae” clade forms the deepest branching lineage and does not form a monophyletic grouping with the “Fortuitum-Vaccae” clade of fast-growing species. In parallel, our comparative analyses of proteins from mycobacterial genomes have identified 172 molecular signatures in the form of conserved signature indels and conserved signature proteins, which are uniquely shared by either all Mycobacterium species or by members of the five identified clades. The identified molecular signatures (or synapomorphies) provide strong independent evidence for the monophyly of the genus Mycobacterium and the five described clades and they provide reliable means for the demarcation of these clades and for their diagnostics. Based on the results of our comprehensive phylogenomic analyses and numerous identified molecular signatures, which consistently and strongly support the division of known mycobacterial species into the five

  18. Phylogenomics and Comparative Genomic Studies Robustly Support Division of the Genus Mycobacterium into an Emended Genus Mycobacterium and Four Novel Genera.

    Science.gov (United States)

    Gupta, Radhey S; Lo, Brian; Son, Jeen

    2018-01-01

    The genus Mycobacterium contains 188 species including several major human pathogens as well as numerous other environmental species. We report here comprehensive phylogenomics and comparative genomic analyses on 150 genomes of Mycobacterium species to understand their interrelationships. Phylogenetic trees were constructed for the 150 species based on 1941 core proteins for the genus Mycobacterium , 136 core proteins for the phylum Actinobacteria and 8 other conserved proteins. Additionally, the overall genome similarity amongst the Mycobacterium species was determined based on average amino acid identity of the conserved protein families. The results from these analyses consistently support the existence of five distinct monophyletic groups within the genus Mycobacterium at the highest level, which are designated as the " Tuberculosis-Simiae ," " Terrae," " Triviale ," " Fortuitum-Vaccae ," and " Abscessus-Chelonae " clades. Some of these clades have also been observed in earlier phylogenetic studies. Of these clades, the " Abscessus-Chelonae" clade forms the deepest branching lineage and does not form a monophyletic grouping with the " Fortuitum-Vaccae " clade of fast-growing species. In parallel, our comparative analyses of proteins from mycobacterial genomes have identified 172 molecular signatures in the form of conserved signature indels and conserved signature proteins, which are uniquely shared by either all Mycobacterium species or by members of the five identified clades. The identified molecular signatures (or synapomorphies) provide strong independent evidence for the monophyly of the genus Mycobacterium and the five described clades and they provide reliable means for the demarcation of these clades and for their diagnostics. Based on the results of our comprehensive phylogenomic analyses and numerous identified molecular signatures, which consistently and strongly support the division of known mycobacterial species into the five described clades, we

  19. Comparative genomics and evolution of the HSP90 family of genes across all kingdoms of organisms

    Directory of Open Access Journals (Sweden)

    Zhong Daibin

    2006-06-01

    Full Text Available Abstract Background HSP90 proteins are essential molecular chaperones involved in signal transduction, cell cycle control, stress management, and folding, degradation, and transport of proteins. HSP90 proteins have been found in a variety of organisms suggesting that they are ancient and conserved. In this study we investigate the nuclear genomes of 32 species across all kingdoms of organisms, and all sequences available in GenBank, and address the diversity, evolution, gene structure, conservation and nomenclature of the HSP90 family of genes across all organisms. Results Twelve new genes and a new type HSP90C2 were identified. The chromosomal location, exon splicing, and prediction of whether they are functional copies were documented, as well as the amino acid length and molecular mass of their polypeptides. The conserved regions across all protein sequences, and signature sequences in each subfamily were determined, and a standardized nomenclature system for this gene family is presented. The proeukaryote HSP90 homologue, HTPG, exists in most Bacteria species but not in Archaea, and it evolved into three lineages (Groups A, B and C via two gene duplication events. None of the organellar-localized HSP90s were derived from endosymbionts of early eukaryotes. Mitochondrial TRAP and endoplasmic reticulum HSP90B separately originated from the ancestors of HTPG Group A in Firmicutes-like organisms very early in the formation of the eukaryotic cell. TRAP is monophyletic and present in all Animalia and some Protista species, while HSP90B is paraphyletic and present in all eukaryotes with the exception of some Fungi species, which appear to have lost it. Both HSP90C (chloroplast HSP90C1 and location-undetermined SP90C2 and cytosolic HSP90A are monophyletic, and originated from HSP90B by independent gene duplications. HSP90C exists only in Plantae, and was duplicated into HSP90C1 and HSP90C2 isoforms in higher plants. HSP90A occurs across all

  20. Comparative genomics of 12 strains of Erwinia amylovora identifies a pan-genome with a large conserved core.

    Directory of Open Access Journals (Sweden)

    Rachel A Mann

    Full Text Available The plant pathogen Erwinia amylovora can be divided into two host-specific groupings; strains infecting a broad range of hosts within the Rosaceae subfamily Spiraeoideae (e.g., Malus, Pyrus, Crataegus, Sorbus and strains infecting Rubus (raspberries and blackberries. Comparative genomic analysis of 12 strains representing distinct populations (e.g., geographic, temporal, host origin of E. amylovora was used to describe the pan-genome of this major pathogen. The pan-genome contains 5751 coding sequences and is highly conserved relative to other phytopathogenic bacteria comprising on average 89% conserved, core genes. The chromosomes of Spiraeoideae-infecting strains were highly homogeneous, while greater genetic diversity was observed between Spiraeoideae- and Rubus-infecting strains (and among individual Rubus-infecting strains, the majority of which was attributed to variable genomic islands. Based on genomic distance scores and phylogenetic analysis, the Rubus-infecting strain ATCC BAA-2158 was genetically more closely related to the Spiraeoideae-infecting strains of E. amylovora than it was to the other Rubus-infecting strains. Analysis of the accessory genomes of Spiraeoideae- and Rubus-infecting strains has identified putative host-specific determinants including variation in the effector protein HopX1(Ea and a putative secondary metabolite pathway only present in Rubus-infecting strains.

  1. Comparative genomics of a drug-resistant Pseudomonas aeruginosa panel and the challenges of antimicrobial resistance prediction from genomes.

    Science.gov (United States)

    Jeukens, J; Kukavica-Ibrulj, I; Emond-Rheault, J G; Freschi, L; Levesque, R C

    2017-10-02

    Antimicrobial resistance (AMR) is now recognized as a global threat to human health. The accessibility of microbial whole-genome sequencing offers an invaluable opportunity for resistance surveillance via the resistome, i.e. the genes and mutations underlying AMR. Unfortunately, AMR prediction from genomic data remains extremely challenging, especially for species with a large pan-genome. One such organism, for which multidrug-resistant (MDR) isolates are frequently encountered in the clinic, is Pseudomonas aeruginosa. This study focuses on a commercially available panel of seven MDR P. aeruginosa strains. The main goals were to sequence and compare these strains' genomes, attempt to predict AMR from whole genomes using two different methods and determine whether this panel could be an informative complement to the international P. aeruginosa reference panel. As expected, the results highlight the complexity of associating genotype and AMR phenotype in P. aeruginosa, mainly due to the intricate regulation of resistance mechanisms. Our results also urge caution in the interpretation of predicted resistomes regarding the occurrence of gene identity discrepancies between strains. We envision that, in addition to accounting for the genomic diversity of P. aeruginosa, future development of predictive tools will need to incorporate a transcriptomic, proteomic and/or metabolomic component. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Array Comparative Genomic Hybridization of Keratoacanthomas and Squamous Cell Carcinomas

    DEFF Research Database (Denmark)

    Li, Jian; Wang, Kai; Gao, Fei

    2012-01-01

    Keratoacanthoma (KA) is a benign keratinocytic neoplasm that spontaneously regresses after 3-6 months and shares features with squamous cell carcinomas (SCCs). Furthermore, there are reports of KAs that have metastasized, invoking the question of whether KA is a variant of SCC (Hodak et al., 1993......). To date, no reported criteria are sensitive enough to discriminate reliably between KA and SCC, and consequently there is a clinical need for discriminating markers. Our previous study analyzed 132 KAs and 29 SCCs and revealed significantly different regions of genomic aberrations using chromosomal...

  3. Self-domestication in Homo sapiens: Insights from comparative genomics.

    Science.gov (United States)

    Theofanopoulou, Constantina; Gastaldon, Simone; O'Rourke, Thomas; Samuels, Bridget D; Messner, Angela; Martins, Pedro Tiago; Delogu, Francesco; Alamri, Saleh; Boeckx, Cedric

    2017-01-01

    This study identifies and analyzes statistically significant overlaps between selective sweep screens in anatomically modern humans and several domesticated species. The results obtained suggest that (paleo-)genomic data can be exploited to complement the fossil record and support the idea of self-domestication in Homo sapiens, a process that likely intensified as our species populated its niche. Our analysis lends support to attempts to capture the "domestication syndrome" in terms of alterations to certain signaling pathways and cell lineages, such as the neural crest.

  4. DNA immunoprecipitation semiconductor sequencing (DIP-SC-seq) as a rapid method to generate genome wide epigenetic signatures

    OpenAIRE

    Thomson, John P.; Fawkes, Angie; Ottaviano, Raffaele; Hunter, Jennifer M.; Shukla, Ruchi; Mjoseng, Heidi K.; Clark, Richard; Coutts, Audrey; Murphy, Lee; Meehan, Richard R.

    2015-01-01

    Modification of DNA resulting in 5-methylcytosine (5 mC) or 5-hydroxymethylcytosine (5hmC) has been shown to influence the local chromatin environment and affect transcription. Although recent advances in next generation sequencing technology allow researchers to map epigenetic modifications across the genome, such experiments are often time-consuming and cost prohibitive. Here we present a rapid and cost effective method of generating genome wide DNA modification maps utilising commercially ...

  5. Characterizing neutral genomic diversity and selection signatures in indigenous populations of Moroccan goats (Capra hircus using WGS data

    Directory of Open Access Journals (Sweden)

    Badr eBenjelloun

    2015-04-01

    Full Text Available Since the time of their domestication, goats (Capra hircus have evolved in a large variety of locally adapted populations in response to different human and environmental pressures. In the present era, many indigenous populations are threatened with extinction due to their substitution by cosmopolitan breeds, while they might represent highly valuable genomic resources. It is thus crucial to characterize the neutral and adaptive genetic diversity of indigenous populations. A fine characterization of whole genome variation in farm animals is now possible by using new sequencing technologies. We sequenced the complete genome at 12X coverage of 44 goats geographically representative of the three phenotypically distinct indigenous populations in Morocco. The study of mitochondrial genomes showed a high diversity exclusively restricted to the haplogroup A. The 44 nuclear genomes showed a very high diversity (24 million variants associated with low linkage disequilibrium. The overall genetic diversity was weakly structured according to geography and phenotypes. When looking for signals of positive selection in each population we identified many candidate genes, several of which gave insights into the metabolic pathways or biological processes involved in the adaptation to local conditions (e.g. panting in warm/desert conditions. This study highlights the interest of WGS data to characterize livestock genomic diversity. It illustrates the valuable genetic richness present in indigenous populations that have to be sustainably managed and may represent valuable genetic resources for the long-term preservation of the species.

  6. A Comparative Survey of the Topographical Distribution of Signature Molecular Lesions in Major Neurodegenerative Diseases

    Science.gov (United States)

    Arnold, Steven E.; Toledo, Jon B.; Appleby, Dina H.; Xie, Sharon X.; Wang, Li-San; Baek, Young; Wolk, David A.; Lee, Edward B.; Miller, Bruce L.; Lee, Virginia M.-Y.; Trojanowski, John Q.

    2013-01-01

    An understanding of the anatomic distributions of major neurodegenerative disease lesions is important to appreciate the differential clinical profiles of these disorders and to serve as neuropathological standards for emerging molecular neuroimaging methods. To address these issues, here we present a comparative survey of the topographical distribution of the defining molecular neuropathological lesions among ten neurodegenerative diseases from a large and uniformly assessed brain collection. Ratings of pathological severity in sixteen brain regions from 671 cases with diverse neurodegenerative diseases were summarized and analyzed. These included: a) amyloid-β and tau lesions in Alzheimer’s disease, b) tau lesions in three other tauopathies including Pick’s disease, progressive supranuclear palsy and corticobasal degeneration, c) α-synuclein inclusion ratings in four synucleinopathies including Parkinson’s disease, Parkinson’s disease with dementia, dementia with Lewy bodies and multiple system atrophy, and d) TDP-43 lesions in two TDP-43 proteinopathies, including frontotemporal lobar degeneration associated with TDP-43 and amyotrophic lateral sclerosis. The data presented graphically and topographically confirm and extend previous pathological anatomic descriptions and statistical comparisons highlight the lesion distributions that either overlap or distinguish the diseases in each molecular disease category. PMID:23881776

  7. Comparative genomics of the bacterial genus Listeria: Genome evolution is characterized by limited gene acquisition and limited gene loss

    Directory of Open Access Journals (Sweden)

    Barker Melissa

    2010-12-01

    Full Text Available Abstract Background The bacterial genus Listeria contains pathogenic and non-pathogenic species, including the pathogens L. monocytogenes and L. ivanovii, both of which carry homologous virulence gene clusters such as the prfA cluster and clusters of internalin genes. Initial evidence for multiple deletions of the prfA cluster during the evolution of Listeria indicates that this genus provides an interesting model for studying the evolution of virulence and also presents practical challenges with regard to definition of pathogenic strains. Results To better understand genome evolution and evolution of virulence characteristics in Listeria, we used a next generation sequencing approach to generate draft genomes for seven strains representing Listeria species or clades for which genome sequences were not available. Comparative analyses of these draft genomes and six publicly available genomes, which together represent the main Listeria species, showed evidence for (i a pangenome with 2,032 core and 2,918 accessory genes identified to date, (ii a critical role of gene loss events in transition of Listeria species from facultative pathogen to saprotroph, even though a consistent pattern of gene loss seemed to be absent, and a number of isolates representing non-pathogenic species still carried some virulence associated genes, and (iii divergence of modern pathogenic and non-pathogenic Listeria species and strains, most likely circa 47 million years ago, from a pathogenic common ancestor that contained key virulence genes. Conclusions Genome evolution in Listeria involved limited gene loss and acquisition as supported by (i a relatively high coverage of the predicted pan-genome by the observed pan-genome, (ii conserved genome size (between 2.8 and 3.2 Mb, and (iii a highly syntenic genome. Limited gene loss in Listeria did include loss of virulence associated genes, likely associated with multiple transitions to a saprotrophic lifestyle. The genus

  8. Delineation of Steroid-Degrading Microorganisms through Comparative Genomic Analysis

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    Lee H. Bergstrand

    2016-03-01

    Full Text Available Steroids are ubiquitous in natural environments and are a significant growth substrate for microorganisms. Microbial steroid metabolism is also important for some pathogens and for biotechnical applications. This study delineated the distribution of aerobic steroid catabolism pathways among over 8,000 microorganisms whose genomes are available in the NCBI RefSeq database. Combined analysis of bacterial, archaeal, and fungal genomes with both hidden Markov models and reciprocal BLAST identified 265 putative steroid degraders within only Actinobacteria and Proteobacteria, which mainly originated from soil, eukaryotic host, and aquatic environments. These bacteria include members of 17 genera not previously known to contain steroid degraders. A pathway for cholesterol degradation was conserved in many actinobacterial genera, particularly in members of the Corynebacterineae, and a pathway for cholate degradation was conserved in members of the genus Rhodococcus. A pathway for testosterone and, sometimes, cholate degradation had a patchy distribution among Proteobacteria. The steroid degradation genes tended to occur within large gene clusters. Growth experiments confirmed bioinformatic predictions of steroid metabolism capacity in nine bacterial strains. The results indicate there was a single ancestral 9,10-seco-steroid degradation pathway. Gene duplication, likely in a progenitor of Rhodococcus, later gave rise to a cholate degradation pathway. Proteobacteria and additional Actinobacteria subsequently obtained a cholate degradation pathway via horizontal gene transfer, in some cases facilitated by plasmids. Catabolism of steroids appears to be an important component of the ecological niches of broad groups of Actinobacteria and individual species of Proteobacteria.

  9. A comparative genomics approach to identifying the plasticity transcriptome

    Directory of Open Access Journals (Sweden)

    Schwartz Russell

    2007-03-01

    Full Text Available Abstract Background Neuronal activity regulates gene expression to control learning and memory, homeostasis of neuronal function, and pathological disease states such as epilepsy. A great deal of experimental evidence supports the involvement of two particular transcription factors in shaping the genomic response to neuronal activity and mediating plasticity: CREB and zif268 (egr-1, krox24, NGFI-A. The gene targets of these two transcription factors are of considerable interest, since they may help develop hypotheses about how neural activity is coupled to changes in neural function. Results We have developed a computational approach for identifying binding sites for these transcription factors within the promoter regions of annotated genes in the mouse, rat, and human genomes. By combining a robust search algorithm to identify discrete binding sites, a comparison of targets across species, and an analysis of binding site locations within promoter regions, we have defined a group of candidate genes that are strong CREB- or zif268 targets and are thus regulated by neural activity. Our analysis revealed that CREB and zif268 share a disproportionate number of targets in common and that these common targets are dominated by transcription factors. Conclusion These observations may enable a more detailed understanding of the regulatory networks that are induced by neural activity and contribute to the plasticity transcriptome. The target genes identified in this study will be a valuable resource for investigators who hope to define the functions of specific genes that underlie activity-dependent changes in neuronal properties.

  10. Draft Genomes, Phylogenetic Reconstruction, and Comparative Genomics of Two Novel Cohabiting Bacterial Symbionts Isolated from Frankliniella occidentalis.

    Science.gov (United States)

    Facey, Paul D; Méric, Guillaume; Hitchings, Matthew D; Pachebat, Justin A; Hegarty, Matt J; Chen, Xiaorui; Morgan, Laura V A; Hoeppner, James E; Whitten, Miranda M A; Kirk, William D J; Dyson, Paul J; Sheppard, Sam K; Del Sol, Ricardo

    2015-07-15

    Obligate bacterial symbionts are widespread in many invertebrates, where they are often confined to specialized host cells and are transmitted directly from mother to progeny. Increasing numbers of these bacteria are being characterized but questions remain about their population structure and evolution. Here we take a comparative genomics approach to investigate two prominent bacterial symbionts (BFo1 and BFo2) isolated from geographically separated populations of western flower thrips, Frankliniella occidentalis. Our multifaceted approach to classifying these symbionts includes concatenated multilocus sequence analysis (MLSA) phylogenies, ribosomal multilocus sequence typing (rMLST), construction of whole-genome phylogenies, and in-depth genomic comparisons. We showed that the BFo1 genome clusters more closely to species in the genus Erwinia, and is a putative close relative to Erwinia aphidicola. BFo1 is also likely to have shared a common ancestor with Erwinia pyrifoliae/Erwinia amylovora and the nonpathogenic Erwinia tasmaniensis and genetic traits similar to Erwinia billingiae. The BFo1 genome contained virulence factors found in the genus Erwinia but represented a divergent lineage. In contrast, we showed that BFo2 belongs within the Enterobacteriales but does not group closely with any currently known bacterial species. Concatenated MLSA phylogenies indicate that it may have shared a common ancestor to the Erwinia and Pantoea genera, and based on the clustering of rMLST genes, it was most closely related to Pantoea ananatis but represented a divergent lineage. We reconstructed a core genome of a putative common ancestor of Erwinia and Pantoea and compared this with the genomes of BFo bacteria. BFo2 possessed none of the virulence determinants that were omnipresent in the Erwinia and Pantoea genera. Taken together, these data are consistent with BFo2 representing a highly novel species that maybe related to known Pantoea. © The Author(s) 2015. Published by

  11. Comparative genomics of 274 Vibrio cholerae genomes reveals mobile functions structuring three niche dimensions

    NARCIS (Netherlands)

    Dutilh, Bas E; Thompson, Cristiane C; Vicente, Ana C P; Marin, Michel A; Lee, Clarence; Silva, Genivaldo G Z; Schmieder, Robert; Andrade, Bruno G N; Chimetto, Luciane; Cuevas, Daniel; Garza, Daniel R; Okeke, Iruka N; Aboderin, Aaron Oladipo; Spangler, Jessica; Ross, Tristen; Dinsdale, Elizabeth A; Thompson, Fabiano L; Harkins, Timothy T; Edwards, Robert A

    2014-01-01

    BACKGROUND: Vibrio cholerae is a globally dispersed pathogen that has evolved with humans for centuries, but also includes non-pathogenic environmental strains. Here, we identify the genomic variability underlying this remarkable persistence across the three major niche dimensions space, time, and

  12. Comparative Genome Analysis Reveals Divergent Genome Size Evolution in a Carnivorous Plant Genus

    Czech Academy of Sciences Publication Activity Database

    Vu, G.T.H.; Schmutzer, T.; Bull, F.; Cao, H.X.; Fuchs, J.; Tran, T.D.; Jovtchev, G.; Pistrick, K.; Stein, N.; Pečinka, A.; Neumann, Pavel; Novák, Petr; Macas, Jiří; Dear, P.H.; Blattner, F.R.; Scholz, U.; Schubert, I.

    2015-01-01

    Roč. 8, č. 3 (2015) ISSN 1940-3372 R&D Projects: GA ČR GBP501/12/G090 Institutional support: RVO:60077344 Keywords : Genlisea * genome * repetitive sequences Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.509, year: 2015

  13. Pathways of aging: comparative analysis of gene signatures in replicative senescence and stress induced premature senescence.

    Science.gov (United States)

    Kural, Kamil C; Tandon, Neetu; Skoblov, Mikhail; Kel-Margoulis, Olga V; Baranova, Ancha V

    2016-12-28

    In culturing normal diploid cells, senescence may either happen naturally, in the form of replicative senescence, or it may be a consequence of external challenges such as oxidative stress. Here we present a comparative analysis aimed at reconstruction of molecular cascades specific for replicative (RS) and stressinduced senescence (SIPS) in human fibroblasts. An involvement of caspase-3/keratin-18 pathway and serine/threonine kinase Aurora A/ MDM2 pathway was shared between RS and SIPS. Moreover, stromelysin/MMP3 and N-acetylglucosaminyltransferase enzyme MGAT1, which initiates the synthesis of hybrid and complex Nglycans, were identified as key orchestrating components in RS and SIPS, respectively. In RS only, Aurora-B driven cell cycle signaling was deregulated in concert with the suppression of anabolic branches of the fatty acids and estrogen metabolism. In SIPS, Aurora-B signaling is deprioritized, and the synthetic branches of cholesterol metabolism are upregulated, rather than downregulated. Moreover, in SIPS, proteasome/ubiquitin ligase pathways of protein degradation dominate the regulatory landscape. This picture indicates that SIPS proceeds in cells that are actively fighting stress which facilitates premature senescence while failing to completely activate the orderly program of RS. The promoters of genes differentially expressed in either RS or SIPS are unusually enriched by the binding sites for homeobox family proteins, with particular emphasis on HMX1, IRX2, HDX and HOXC13. Additionally, we identified Iroquois Homeobox 2 (IRX2) as a master regulator for the secretion of SPP1-encoded osteopontin, a stromal driver for tumor growth that is overexpressed by both RS and SIPS fibroblasts. The latter supports the hypothesis that senescence-specific de-repression of SPP1 aids in SIPS-dependent stromal activation. Reanalysis of previously published experimental data is cost-effective approach for extraction of additional insignts into the functioning of

  14. Comparison of chromosomal and array-based comparative genomic hybridization for the detection of genomic imbalances in primary prostate carcinomas

    Directory of Open Access Journals (Sweden)

    Berg Marianne

    2006-09-01

    Full Text Available Abstract Background In order to gain new insights into the molecular mechanisms involved in prostate cancer, we performed array-based comparative genomic hybridization (aCGH on a series of 46 primary prostate carcinomas using a 1 Mbp whole-genome coverage platform. As chromosomal comparative genomic hybridization (cCGH data was available for these samples, we compared the sensitivity and overall concordance of the two methodologies, and used the combined information to infer the best of three different aCGH scoring approaches. Results Our data demonstrate that the reliability of aCGH in the analysis of primary prostate carcinomas depends to some extent on the scoring approach used, with the breakpoint estimation method being the most sensitive and reliable. The pattern of copy number changes detected by aCGH was concordant with that of cCGH, but the higher resolution technique detected 2.7 times more aberrations and 15.2% more carcinomas with genomic imbalances. We additionally show that several aberrations were consistently overlooked using cCGH, such as small deletions at 5q, 6q, 12p, and 17p. The latter were validated by fluorescence in situ hybridization targeting TP53, although only one carcinoma harbored a point mutation in this gene. Strikingly, homozygous deletions at 10q23.31, encompassing the PTEN locus, were seen in 58% of the cases with 10q loss. Conclusion We conclude that aCGH can significantly improve the detection of genomic aberrations in cancer cells as compared to previously established whole-genome methodologies, although contamination with normal cells may influence the sensitivity and specificity of some scoring approaches. Our work delineated recurrent copy number changes and revealed novel amplified loci and frequent homozygous deletions in primary prostate carcinomas, which may guide future work aimed at identifying the relevant target genes. In particular, biallelic loss seems to be a frequent mechanism of inactivation

  15. Using Sybil for interactive comparative genomics of microbes on the web.

    Science.gov (United States)

    Riley, David R; Angiuoli, Samuel V; Crabtree, Jonathan; Dunning Hotopp, Julie C; Tettelin, Hervé

    2012-01-15

    Analysis of multiple genomes requires sophisticated tools that provide search, visualization, interactivity and data export. Comparative genomics datasets tend to be large and complex, making development of these tools difficult. In addition to scalability, comparative genomics tools must also provide user-friendly interfaces such that the research scientist can explore complex data with minimal technical expertise. We describe a new version of the Sybil software package and its application to the important human pathogen Streptococcus pneumoniae. This new software provides a feature-rich set of comparative genomics tools for inspection of multiple genome structures, mining of orthologous gene families and identification of potential vaccine candidates. The S.pneumoniae resource is online at http://strepneumo-sybil.igs.umaryland.edu. The software, database and website are available for download as a portable virtual machine and from http://sourceforge.net/projects/sybil.

  16. Génolevures: comparative genomics and molecular evolution of hemiascomycetous yeasts

    Science.gov (United States)

    Sherman, David; Durrens, Pascal; Beyne, Emmanuelle; Nikolski, Macha; Souciet, Jean-Luc

    2004-01-01

    The Génolevures online database (http://cbi.labri.fr/Genolevures/) provides data and tools to facilitate comparative genomic studies on hemiascomycetous yeasts. Now, four complete genome sequences recently determined (Candida glabrata, Kluyveromyces lactis, Debaryomyces hansenii, Yarrowia lipolytica) have been added to the partial sequences of 13 species previously analysed by a random approach. The database also includes the reference genome Saccharomyces cerevisiae. Data are presented with a focus on relations between genes and genomes: conservation of genes and gene families, speciation, chromosomal reorganization and synteny. The Génolevures site includes a community area for specific studies by members of the international community. PMID:14681422

  17. The use of comparative genomic hybridization to characterize genome dynamics and diversity among the serotypes of Shigella

    Directory of Open Access Journals (Sweden)

    Sun Meisheng

    2006-08-01

    Full Text Available Abstract Background Compelling evidence indicates that Shigella species, the etiologic agents of bacillary dysentery, as well as enteroinvasive Escherichia coli, are derived from multiple origins of Escherichia coli and form a single pathovar. To further understand the genome diversity and virulence evolution of Shigella, comparative genomic hybridization microarray analysis was employed to compare the gene content of E. coli K-12 with those of 43 Shigella strains from all lineages. Results For the 43 strains subjected to CGH microarray analyses, the common backbone of the Shigella genome was estimated to contain more than 1,900 open reading frames (ORFs, with a mean number of 726 undetectable ORFs. The mosaic distribution of absent regions indicated that insertions and/or deletions have led to the highly diversified genomes of pathogenic strains. Conclusion These results support the hypothesis that by gain and loss of functions, Shigella species became successful human pathogens through convergent evolution from diverse genomic backgrounds. Moreover, we also found many specific differences between different lineages, providing a window into understanding bacterial speciation and taxonomic relationships.

  18. Functional and comparative genome analysis of novel virulent actinophages belonging to Streptomyces flavovirens

    Czech Academy of Sciences Publication Activity Database

    Sharaf, Abdoallah; Mercati, F.; Elmaghraby, I.; Elbaz, R. M.; Marei, E. M.

    2017-01-01

    Roč. 17, 3 March (2017), č. článku 51. ISSN 1471-2180 Institutional support: RVO:60077344 Keywords : bacteriophage * biological stability * whole genome sequence * ngs * comparative genomics Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 2.644, year: 2016

  19. Array-based comparative genomic hybridization for the differential diagnosis of renal cell cancer.

    NARCIS (Netherlands)

    Wilhelm, M.; Veltman, J.A.; Olshen, A.B.; Jain, A.N.; Moore, D.H.; Presti Jr, J.C.; Kovacs, G.; Waldman, F.M.

    2002-01-01

    Array-based comparative genomic hybridization (CGH) uses multiple genomic clones arrayed on a slide to detect relative copy number of tumor DNA sequences. Application of array CGH to tumor specimens makes genetic diagnosis of cancers possible and may help to differentiate relevant subsets of tumors,

  20. Campylobacter fetus subspecies: Comparative genomics and prediction of potential virulence targets

    DEFF Research Database (Denmark)

    Ali, Amjad; Soares, Siomar C.; Santos, Anderson R.

    2012-01-01

    The genus Campylobacter contains pathogens causing a wide range of diseases, targeting both humans and animals. Among them, the Campylobacter fetus subspecies fetus and venerealis deserve special attention, as they are the etiological agents of human bacterial gastroenteritis and bovine genital...... campylobacteriosis, respectively. We compare the whole genomes of both subspecies to get insights into genomic architecture, phylogenetic relationships, genome conservation and core virulence factors. Pan-genomic approach was applied to identify the core- and pan-genome for both C. fetus subspecies and members...... of the genus. The C. fetus subspecies conserved (76%) proteome were then analyzed for their subcellular localization and protein functions in biological processes. Furthermore, with pathogenomic strategies, unique candidate regions in the genomes and several potential core-virulence factors were identified...

  1. The population genomic signature of environmental association and gene flow in an ecologically divergent tree species Metrosideros polymorpha (Myrtaceae).

    Science.gov (United States)

    Izuno, Ayako; Kitayama, Kanehiro; Onoda, Yusuke; Tsujii, Yuki; Hatakeyama, Masaomi; Nagano, Atsushi J; Honjo, Mie N; Shimizu-Inatsugi, Rie; Kudoh, Hiroshi; Shimizu, Kentaro K; Isagi, Yuji

    2017-03-01

    Genomewide markers enable us to study genetic differentiation within a species and the factors underlying it at a much higher resolution than before, which advances our understanding of adaptation in organisms. We investigated genomic divergence in Metrosideros polymorpha, a woody species that occupies a wide range of ecological habitats across the Hawaiian Islands and shows remarkable phenotypic variation. Using 1659 single nucleotide polymorphism (SNP) markers annotated with the genome assembly, we examined the population genetic structure and demographic history of nine populations across five elevations and two ages of substrates on Mauna Loa, the island of Hawaii. The nine populations were differentiated into two genetic clusters distributed on the lower and higher elevations and were largely admixed on the middle elevation. Demographic modelling revealed that the two genetic clusters have been maintained in the face of gene flow, and the effective population size of the high-altitude cluster was much smaller. A F ST -based outlier search among the 1659 SNPs revealed that 34 SNPs (2.05%) were likely to be under divergent selection and the allele frequencies of 21 of them were associated with environmental changes along elevations, such as temperature and precipitation. This study shows a genomic mosaic of M. polymorpha, in which contrasting divergence patterns were found. While most genomic polymorphisms were shared among populations, a small fraction of the genome was significantly differentiated between populations in diverse environments and could be responsible for the dramatic adaptation to a wide range of environments. © 2017 John Wiley & Sons Ltd.

  2. Genome-wide analysis reveals signatures of selection for important traits in domestic sheep from different ecoregions.

    Science.gov (United States)

    Liu, Zhaohua; Ji, Zhibin; Wang, Guizhi; Chao, Tianle; Hou, Lei; Wang, Jianmin

    2016-11-03

    Throughout a long period of adaptation and selection, sheep have thrived in a diverse range of ecological environments. Mongolian sheep is the common ancestor of the Chinese short fat-tailed sheep. Migration to different ecoregions leads to changes in selection pressures and results in microevolution. Mongolian sheep and its subspecies differ in a number of important traits, especially reproductive traits. Genome-wide intraspecific variation is required to dissect the genetic basis of these traits. This research resequenced 3 short fat-tailed sheep breeds with a 43.2-fold coverage of the sheep genome. We report more than 17 million single nucleotide polymorphisms and 2.9 million indels and identify 143 genomic regions with reduced pooled heterozygosity or increased genetic distance to each other breed that represent likely targets for selection during the migration. These regions harbor genes related to developmental processes, cellular processes, multicellular organismal processes, biological regulation, metabolic processes, reproduction, localization, growth and various components of the stress responses. Furthermore, we examined the haplotype diversity of 3 genomic regions involved in reproduction and found significant differences in TSHR and PRL gene regions among 8 sheep breeds. Our results provide useful genomic information for identifying genes or causal mutations associated with important economic traits in sheep and for understanding the genetic basis of adaptation to different ecological environments.

  3. Molecular Aspects and Comparative Genomics of Bacteriophage Endolysins

    Science.gov (United States)

    Oliveira, Hugo; Melo, Luís D. R.; Santos, Sílvio B.; Nóbrega, Franklin L.; Ferreira, Eugénio C.; Cerca, Nuno; Azeredo, Joana

    2013-01-01

    Phages are recognized as the most abundant and diverse entities on the planet. Their diversity is determined predominantly by their dynamic adaptation capacities when confronted with different selective pressures in an endless cycle of coevolution with a widespread group of bacterial hosts. At the end of the infection cycle, progeny virions are confronted with a rigid cell wall that hinders their release into the environment and the opportunity to start a new infection cycle. Consequently, phages encode hydrolytic enzymes, called endolysins, to digest the peptidoglycan. In this work, we bring to light all phage endolysins found in completely sequenced double-stranded nucleic acid phage genomes and uncover clues that explain the phage-endolysin-host ecology that led phages to recruit unique and specialized endolysins. PMID:23408602

  4. Species Choice for Comparative Genomics: Being Greedy Works.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available Several projects investigating genetic function and evolution through sequencing and comparison of multiple genomes are now underway. These projects consume many resources, and appropriate planning should be devoted to choosing which species to sequence, potentially involving cooperation among different sequencing centres. A widely discussed criterion for species choice is the maximisation of evolutionary divergence. Our mathematical formalization of this problem surprisingly shows that the best long-term cooperative strategy coincides with the seemingly short-term "greedy" strategy of always choosing the next best single species. Other criteria influencing species choice, such as medical relevance or sequencing costs, can also be accommodated in our approach, suggesting our results' broad relevance in scientific policy decisions.

  5. Comparative genomics of the syndecans defines an ancestral genomic context associated with matrilins in vertebrates

    Directory of Open Access Journals (Sweden)

    Adams Josephine C

    2006-04-01

    Full Text Available Abstract Background The syndecans are the major family of transmembrane proteoglycans in animals and are known for multiple roles in cell interactions and growth factor signalling during development, inflammatory response, wound-repair and tumorigenesis. Although syndecans have been cloned from several invertebrate and vertebrate species, the extent of conservation of the family across the animal kingdom is unknown and there are gaps in our knowledge of chordate syndecans. Here, we develop a new level of knowledge for the whole syndecan family, by combining molecular phylogeny of syndecan protein sequences with analysis of the genomic contexts of syndecan genes in multiple vertebrate organisms. Results We identified syndecan-encoding sequences in representative Cnidaria and throughout the Bilateria. The C1 and C2 regions of the cytoplasmic domain are highly conserved throughout the animal kingdom. We identified in the variable region a universally-conserved leucine residue and a tyrosine residue that is conserved throughout the Bilateria. Of all the genomes examined, only tetrapod and fish genomes encode multiple syndecans. No syndecan-1 was identified in fish. The genomic context of each vertebrate syndecan gene is syntenic between human, mouse and chicken, and this conservation clearly extends to syndecan-2 and -3 in T. nigroviridis. In addition, tetrapod syndecans were found to be encoded from paralogous chromosomal regions that also contain the four members of the matrilin family. Whereas the matrilin-3 and syndecan-1 genes are adjacent in tetrapods, this chromosomal region appears to have undergone extensive lineage-specific rearrangements in fish. Conclusion Throughout the animal kingdom, syndecan extracellular domains have undergone rapid change and elements of the cytoplasmic domains have been very conserved. The four syndecan genes of vertebrates are syntenic across tetrapods, and synteny of the syndecan-2 and -3 genes is apparent

  6. Comparative genomics of regulation of heavy metal resistance in Eubacteria

    Directory of Open Access Journals (Sweden)

    Kalinina OV

    2006-06-01

    Full Text Available Abstract Background Heavy metal resistance (HMR in Eubacteria is regulated by a variety of systems including transcription factors from the MerR family (COG0789. The HMR systems are characterized by the complex signal structure (strong palindrome within a 19 or 20 bp promoter spacer, and usually consist of transporter and regulator genes. Some HMR regulons also include detoxification systems. The number of sequenced bacterial genomes is constantly increasing and even though HMR resistance regulons of the COG0789 type usually consist of few genes per genome, the computational analysis may contribute to the understanding of the cellular systems of metal detoxification. Results We studied the mercury (MerR, copper (CueR and HmrR, cadmium (CadR, lead (PbrR, and zinc (ZntR resistance systems and demonstrated that combining protein sequence analysis and analysis of DNA regulatory signals it was possible to distinguish metal-dependent members of COG0789, assign specificity towards particular metals to uncharacterized loci, and find new genes involved in the metal resistance, in particular, multicopper oxidase and copper chaperones, candidate cytochromes from the copper regulon, new cadmium transporters and, possibly, glutathione-S-transferases. Conclusion Our data indicate that the specificity of the COG0789 systems can be determined combining phylogenetic analysis and identification of DNA regulatory sites. Taking into account signal structure, we can adequately identify genes that are activated using the DNA bending-unbending mechanism. In the case of regulon members that do not reside in single loci, analysis of potential regulatory sites could be crucial for the correct annotation and prediction of the specificity.

  7. A parts list for fungal cellulosomes revealed by comparative genomics

    Energy Technology Data Exchange (ETDEWEB)

    Haitjema, Charles H.; Gilmore, Sean P.; Henske, John K.; Solomon, Kevin V.; de Groot, Randall; Kuo, Alan; Mondo, Stephen J.; Salamov, Asaf A.; LaButti, Kurt; Zhao, Zhiying; Chiniquy, Jennifer; Barry, Kerrie; Brewer, Heather M.; Purvine, Samuel O.; Wright, Aaron T.; Hainaut, Matthieu; Boxma, Brigitte; van Alen, Theo; Hackstein, Johannes H. P.; Henrissat, Bernard; Baker, Scott E.; Grigoriev, Igor V.; O' Malley, Michelle A.

    2017-05-26

    Cellulosomes are large, multi-protein complexes that tether plant biomass degrading enzymes together for improved hydrolysis1. These complexes were first described in anaerobic bacteria where species specific dockerin domains mediate assembly of enzymes onto complementary cohesin motifs interspersed within non-catalytic protein scaffolds1. The versatile protein assembly mechanism conferred by the bacterial cohesin-dockerin interaction is now a standard design principle for synthetic protein-scale pathways2,3. For decades, analogous structures have been reported in the early branching anaerobic fungi, which are known to assemble by sequence divergent non-catalytic dockerin domains (NCDD)4. However, the enzyme components, modular assembly mechanism, and functional role of fungal cellulosomes remain unknown5,6. Here, we describe the comprehensive set of proteins critical to fungal cellulosome assembly, including novel, conserved scaffolding proteins unique to the Neocallimastigomycota. High quality genomes of the anaerobic fungi Anaeromyces robustus, Neocallimastix californiae and Piromyces finnis were assembled with long-read, single molecule technology to overcome their repeat-richness and extremely low GC content. Genomic analysis coupled with proteomic validation revealed an average 320 NCDD-containing proteins per fungal strain that were overwhelmingly carbohydrate active enzymes (CAZymes), with 95 large fungal scaffoldins identified across 4 genera that contain a conserved amino acid sequence repeat that binds to NCDDs. Fungal dockerin and scaffoldin domains have no similarity to their bacterial counterparts, yet several catalytic domains originated via horizontal gene transfer with gut bacteria. Though many catalytic domains are shared with bacteria, the biocatalytic activity of anaerobic fungi is expanded by the inclusion of GH3, GH6, and GH45 enzymes in the enzyme complexes. Collectively, these findings suggest that the fungal cellulosome is an evolutionarily

  8. Comparative genomic analysis of human fungal pathogens causing paracoccidioidomycosis.

    Directory of Open Access Journals (Sweden)

    Christopher A Desjardins

    2011-10-01

    Full Text Available Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18 and one strain of Paracoccidioides lutzii (Pb01. These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic

  9. Identification of conserved regulatory elements by comparative genome analysis

    Directory of Open Access Journals (Sweden)

    Jareborg Niclas

    2003-05-01

    Full Text Available Abstract Background For genes that have been successfully delineated within the human genome sequence, most regulatory sequences remain to be elucidated. The annotation and interpretation process requires additional data resources and significant improvements in computational methods for the detection of regulatory regions. One approach of growing popularity is based on the preferential conservation of functional sequences over the course of evolution by selective pressure, termed 'phylogenetic footprinting'. Mutations are more likely to be disruptive if they appear in functional sites, resulting in a measurable difference in evolution rates between functional and non-functional genomic segments. Results We have devised a flexible suite of methods for the identification and visualization of conserved transcription-factor-binding sites. The system reports those putative transcription-factor-binding sites that are both situated in conserved regions and located as pairs of sites in equivalent positions in alignments between two orthologous sequences. An underlying collection of metazoan transcription-factor-binding profiles was assembled to facilitate the study. This approach results in a significant improvement in the detection of transcription-factor-binding sites because of an increased signal-to-noise ratio, as demonstrated with two sets of promoter sequences. The method is implemented as a graphical web application, ConSite, which is at the disposal of the scientific community at http://www.phylofoot.org/. Conclusions Phylogenetic footprinting dramatically improves the predictive selectivity of bioinformatic approaches to the analysis of promoter sequences. ConSite delivers unparalleled performance using a novel database of high-quality binding models for metazoan transcription factors. With a dynamic interface, this bioinformatics tool provides broad access to promoter analysis with phylogenetic footprinting.

  10. Comparative genomics of proteins involved in RNA nucleocytoplasmic export.

    Science.gov (United States)

    Serpeloni, Mariana; Vidal, Newton M; Goldenberg, Samuel; Avila, Andréa R; Hoffmann, Federico G

    2011-01-11

    The establishment of the nuclear membrane resulted in the physical separation of transcription and translation, and presented early eukaryotes with a formidable challenge: how to shuttle RNA from the nucleus to the locus of protein synthesis. In prokaryotes, mRNA is translated as it is being synthesized, whereas in eukaryotes mRNA is synthesized and processed in the nucleus, and it is then exported to the cytoplasm. In metazoa and fungi, the different RNA species are exported from the nucleus by specialized pathways. For example, tRNA is exported by exportin-t in a RanGTP-dependent fashion. By contrast, mRNAs are associated to ribonucleoproteins (RNPs) and exported by an essential shuttling complex (TAP-p15 in human, Mex67-mtr2 in yeast) that transports them through the nuclear pore. The different RNA export pathways appear to be well conserved among members of Opisthokonta, the eukaryotic supergroup that includes Fungi and Metazoa. However, it is not known whether RNA export in the other eukaryotic supergroups follows the same export routes as in opisthokonts. Our objective was to reconstruct the evolutionary history of the different RNA export pathways across eukaryotes. To do so, we screened an array of eukaryotic genomes for the presence of homologs of the proteins involved in RNA export in Metazoa and Fungi, using human and yeast proteins as queries. Our genomic comparisons indicate that the basic components of the RanGTP-dependent RNA pathways are conserved across eukaryotes, and thus we infer that these are traceable to the last eukaryotic common ancestor (LECA). On the other hand, several of the proteins involved in RanGTP-independent mRNA export pathways are less conserved, which would suggest that they represent innovations that appeared later in the evolution of eukaryotes. Our analyses suggest that the LECA possessed the basic components of the different RNA export mechanisms found today in opisthokonts, and that these mechanisms became more specialized

  11. Implications of genomic signatures in the differential vulnerability to fetal alcohol exposure in C57BL/6 and DBA/2 mice

    Directory of Open Access Journals (Sweden)

    Amy C. Lossie

    2014-06-01

    Full Text Available Maternal alcohol consumption inflicts a multitude of phenotypic consequences that range from undetectable changes to severe dysmorphology. Using tightly controlled murine studies that deliver precise amounts of alcohol at discrete developmental stages, our group and other labs demonstrated in prior studies that the C57BL/6 and DBA/2 inbred mouse strains display differential susceptibility to the teratogenic effects of alcohol. Since the phenotypic diversity extends beyond the amount, dosage and timing of alcohol exposure, it is likely that an individual’s genetic background contributes to the phenotypic spectrum. To identify the genomic signatures associated with these observed differences in alcohol-induced dysmorphology, we conducted a microarray-based transcriptome study that also interrogated the genomic signatures between these two lines based on genetic background and alcohol exposure. This approach is called a gene x environment (GxE analysis; one example of a GxE interaction would be a gene whose expression level increases in C57BL/6 animals, but decreases in DBA/2 embryos, following alcohol exposure. We identified 35 candidate genes exhibiting GxE interactions. To identify cis-acting factors that mediated these interactions, we interrogated the proximal promoters of these 35 candidates and found 241 single nucleotide variants (SNVs in 16 promoters. Further investigation indicated that 186 SNVs (15 promoters are predicted to alter transcription factor binding. In addition, 62 SNVs created, removed or altered the placement of a CpG dinucleotide in 13 of the proximal promoters; 53 of which overlapped putative transcription factor binding sites. These 53 SNVs are our top candidates for future studies aimed at examining the effects of alcohol on epigenetic gene regulation.

  12. A genomic biomarker signature can predict skin sensitizers using a cell-based in vitro alternative to animal tests

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    Albrekt Ann-Sofie

    2011-08-01

    Full Text Available Abstract Background Allergic contact dermatitis is an inflammatory skin disease that affects a significant proportion of the population. This disease is caused by an adverse immune response towards chemical haptens, and leads to a substantial economic burden for society. Current test of sensitizing chemicals rely on animal experimentation. New legislations on the registration and use of chemicals within pharmaceutical and cosmetic industries have stimulated significant research efforts to develop alternative, human cell-based assays for the prediction of sensitization. The aim is to replace animal experiments with in vitro tests displaying a higher predictive power. Results We have developed a novel cell-based assay for the prediction of sensitizing chemicals. By analyzing the transcriptome of the human cell line MUTZ-3 after 24 h stimulation, using 20 different sensitizing chemicals, 20 non-sensitizing chemicals and vehicle controls, we have identified a biomarker signature of 200 genes with potent discriminatory ability. Using a Support Vector Machine for supervised classification, the prediction performance of the assay revealed an area under the ROC curve of 0.98. In addition, categorizing the chemicals according to the LLNA assay, this gene signature could also predict sensitizing potency. The identified markers are involved in biological pathways with immunological relevant functions, which can shed light on the process of human sensitization. Conclusions A gene signature predicting sensitization, using a human cell line in vitro, has been identified. This simple and robust cell-based assay has the potential to completely replace or drastically reduce the utilization of test systems based on experimental animals. Being based on human biology, the assay is proposed to be more accurate for predicting sensitization in humans, than the traditional animal-based tests.

  13. New Markov Model Approaches to Deciphering Microbial Genome Function and Evolution: Comparative Genomics of Laterally Transferred Genes

    Energy Technology Data Exchange (ETDEWEB)

    Borodovsky, M.

    2013-04-11

    Algorithmic methods for gene prediction have been developed and successfully applied to many different prokaryotic genome sequences. As the set of genes in a particular genome is not homogeneous with respect to DNA sequence composition features, the GeneMark.hmm program utilizes two Markov models representing distinct classes of protein coding genes denoted "typical" and "atypical". Atypical genes are those whose DNA features deviate significantly from those classified as typical and they represent approximately 10% of any given genome. In addition to the inherent interest of more accurately predicting genes, the atypical status of these genes may also reflect their separate evolutionary ancestry from other genes in that genome. We hypothesize that atypical genes are largely comprised of those genes that have been relatively recently acquired through lateral gene transfer (LGT). If so, what fraction of atypical genes are such bona fide LGTs? We have made atypical gene predictions for all fully completed prokaryotic genomes; we have been able to compare these results to other "surrogate" methods of LGT prediction.

  14. The role of duplications in the evolution of genomes highlights the need for evolutionary-based approaches in comparative genomics

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    Levasseur Anthony

    2011-02-01

    Full Text Available Abstract Understanding the evolutionary plasticity of the genome requires a global, comparative approach in which genetic events are considered both in a phylogenetic framework and with regard to population genetics and environmental variables. In the mechanisms that generate adaptive and non-adaptive changes in genomes, segmental duplications (duplication of individual genes or genomic regions and polyploidization (whole genome duplications are well-known driving forces. The probability of fixation and maintenance of duplicates depends on many variables, including population sizes and selection regimes experienced by the corresponding genes: a combination of stochastic and adaptive mechanisms has shaped all genomes. A survey of experimental work shows that the distinction made between fixation and maintenance of duplicates still needs to be conceptualized and mathematically modeled. Here we review the mechanisms that increase or decrease the probability of fixation or maintenance of duplicated genes, and examine the outcome of these events on the adaptation of the organisms. Reviewers This article was reviewed by Dr. Etienne Joly, Dr. Lutz Walter and Dr. W. Ford Doolittle.

  15. Analysis of the Complete Chloroplast Genome of a Medicinal Plant, Dianthus superbus var. longicalyncinus, from a Comparative Genomics Perspective.

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    Gurusamy Raman

    Full Text Available Dianthus superbus var. longicalycinus is an economically important traditional Chinese medicinal plant that is also used for ornamental purposes. In this study, D. superbus was compared to its closely related family of Caryophyllaceae chloroplast (cp genomes such as Lychnis chalcedonica and Spinacia oleracea. D. superbus had the longest large single copy (LSC region (82,805 bp, with some variations in the inverted repeat region A (IRA/LSC regions. The IRs underwent both expansion and constriction during evolution of the Caryophyllaceae family; however, intense variations were not identified. The pseudogene ribosomal protein subunit S19 (rps19 was identified at the IRA/LSC junction, but was not present in the cp genome of other Caryophyllaceae family members. The translation initiation factor IF-1 (infA and ribosomal protein subunit L23 (rpl23 genes were absent from the Dianthus cp genome. When the cp genome of Dianthus was compared with 31 other angiosperm lineages, the infA gene was found to have been lost in most members of rosids, solanales of asterids and Lychnis of Caryophyllales, whereas rpl23 gene loss or pseudogization had occurred exclusively in Caryophyllales. Nevertheless, the cp genome of Dianthus and Spinacia has two introns in the proteolytic subunit of ATP-dependent protease (clpP gene, but Lychnis has lost introns from the clpP gene. Furthermore, phylogenetic analysis of individual protein-coding genes infA and rpl23 revealed that gene loss or pseudogenization occurred independently in the cp genome of Dianthus. Molecular phylogenetic analysis also demonstrated a sister relationship between Dianthus and Lychnis based on 78 protein-coding sequences. The results presented herein will contribute to studies of the evolution, molecular biology and genetic engineering of the medicinal and ornamental plant, D. superbus var. longicalycinus.

  16. Integrating cytogenetics and genomics in comparative evolutionary studies of cichlid fish

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    Mazzuchelli Juliana

    2012-09-01

    Full Text Available Abstract Background The availability of a large number of recently sequenced vertebrate genomes opens new avenues to integrate cytogenetics and genomics in comparative and evolutionary studies. Cytogenetic mapping can offer alternative means to identify conserved synteny shared by distinct genomes and also to define genome regions that are still not fine characterized even after wide-ranging nucleotide sequence efforts. An efficient way to perform comparative cytogenetic mapping is based on BAC clones mapping by fluorescence in situ hybridization. In this report, to address the knowledge gap on the genome evolution in cichlid fishes, BAC clones of an Oreochromis niloticus library covering the linkage groups (LG 1, 3, 5, and 7 were mapped onto the chromosomes of 9 African cichlid species. The cytogenetic mapping data were also integrated with BAC-end sequences information of O. niloticus and comparatively analyzed against the genome of other fish species and vertebrates. Results The location of BACs from LG1, 3, 5, and 7 revealed a strong chromosomal conservation among the analyzed cichlid species genomes, which evidenced a synteny of the markers of each LG. Comparative in silico analysis also identified large genomic blocks that were conserved in distantly related fish groups and also in other vertebrates. Conclusions Although it has been suggested that fishes contain plastic genomes with high rates of chromosomal rearrangements and probably low rates of synteny conservation, our results evidence that large syntenic chromosome segments have been maintained conserved during evolution, at least for the considered markers. Additionally, our current cytogenetic mapping efforts integrated with genomic approaches conduct to a new perspective to address important questions involving chromosome evolution in fishes.

  17. Mutational signatures reveal the role of RAD52 in p53-independent p21-driven genomic instability

    DEFF Research Database (Denmark)

    Galanos, Panagiotis; Pappas, George; Polyzos, Alexander

    2018-01-01

    BACKGROUND: Genomic instability promotes evolution and heterogeneity of tumors. Unraveling its mechanistic basis is essential for the design of appropriate therapeutic strategies. In a previous study, we reported an unexpected oncogenic property of p21WAF1/Cip1, showing that its chronic expressio...

  18. Global population genomics and comparisons of selective signatures from two invasions of melon fly, Zeugodacus cucurbitae (Diptera: Tephritidae)

    Science.gov (United States)

    Population genetics is a powerful tool for invasion biology and pest management, from tracing invasion pathways to informing management decisions with inference of population demographics. Genomics greatly increases the resolution of population-scale analyses, yet outside of model species with exten...

  19. Comparative genome analysis and resistance gene mapping in grain legumes

    International Nuclear Information System (INIS)

    Young, N.D.

    1998-01-01

    Using, DNA markers and genome organization, several important disease resistance genes have been analyzed in mungbean (Vigna radiata), cowpea (Vigna unguiculata), common bean (Phaseolus vulgaris), and soybean (Glycine max). In the process, medium-density linkage maps consisting of restriction fragment length polymorphism (RFLP) markers were constructed for both mungbean and cowpea. Comparisons between these maps, as well as the maps of soybean and common bean, indicate that there is significant conservation of DNA marker order, though the conserved blocks in soybean are much shorter than in the others. DNA mapping results also indicate that a gene for seed weight may be conserved between mungbean and cowpea. Using the linkage maps, genes that control bruchid (genus Callosobruchus) and powdery mildew (Erysiphe polygoni) resistance in mungbean, aphid resistance in cowpea (Aphis craccivora), and cyst nematode (Heterodera glycines) resistance in soybean have all been mapped and characterized. For some of these traits resistance was found to be oligogenic and DNA mapping uncovered multiple genes involved in the phenotype. (author)

  20. Comparative analyses of multi-species sequences from targeted genomic regions.

    Science.gov (United States)

    Thomas, J W; Touchman, J W; Blakesley, R W; Bouffard, G G; Beckstrom-Sternberg, S M; Margulies, E H; Blanchette, M; Siepel, A C; Thomas, P J; McDowell, J C; Maskeri, B; Hansen, N F; Schwartz, M S; Weber, R J; Kent, W J; Karolchik, D; Bruen, T C; Bevan, R; Cutler, D J; Schwartz, S; Elnitski, L; Idol, J R; Prasad, A B; Lee-Lin, S-Q; Maduro, V V B; Summers, T J; Portnoy, M E; Dietrich, N L; Akhter, N; Ayele, K; Benjamin, B; Cariaga, K; Brinkley, C P; Brooks, S Y; Granite, S; Guan, X; Gupta, J; Haghighi, P; Ho, S-L; Huang, M C; Karlins, E; Laric, P L; Legaspi, R; Lim, M J; Maduro, Q L; Masiello, C A; Mastrian, S D; McCloskey, J C; Pearson, R; Stantripop, S; Tiongson, E E; Tran, J T; Tsurgeon, C; Vogt, J L; Walker, M A; Wetherby, K D; Wiggins, L S; Young, A C; Zhang, L-H; Osoegawa, K; Zhu, B; Zhao, B; Shu, C L; De Jong, P J; Lawrence, C E; Smit, A F; Chakravarti, A; Haussler, D; Green, P; Miller, W; Green, E D

    2003-08-14

    The systematic comparison of genomic sequences from different organisms represents a central focus of contemporary genome analysis. Comparative analyses of vertebrate sequences can identify coding and conserved non-coding regions, including regulatory elements, and provide insight into the forces that have rendered modern-day genomes. As a complement to whole-genome sequencing efforts, we are sequencing and comparing targeted genomic regions in multiple, evolutionarily diverse vertebrates. Here we report the generation and analysis of over 12 megabases (Mb) of sequence from 12 species, all derived from the genomic region orthologous to a segment of about 1.8 Mb on human chromosome 7 containing ten genes, including the gene mutated in cystic fibrosis. These sequences show conservation reflecting both functional constraints and the neutral mutational events that shaped this genomic region. In particular, we identify substantial numbers of conserved non-coding segments beyond those previously identified experimentally, most of which are not detectable by pair-wise sequence comparisons alone. Analysis of transposable element insertions highlights the variation in genome dynamics among these species and confirms the placement of rodents as a sister group to the primates.

  1. Comparative genomics of bacteria in the genus Providencia isolated from wild Drosophila melanogaster

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    Galac Madeline R

    2012-11-01

    Full Text Available Abstract Background Comparative genomics can be an initial step in finding the genetic basis for phenotypic differences among bacterial strains and species. Bacteria belonging to the genus Providencia have been isolated from numerous and varied environments. We sequenced, annotated and compared draft genomes of P. rettgeri, P. sneebia, P. alcalifaciens, and P. burhodogranariea. These bacterial species that were all originally isolated as infections of wild Drosophila melanogaster and have been previously shown to vary in virulence to experimentally infected flies. Results We found that these Providencia species share a large core genome, but also possess distinct sets of genes that are unique to each isolate. We compared the genomes of these isolates to draft genomes of four Providencia isolated from the human gut and found that the core genome size does not substantially change upon inclusion of the human isolates. We found many adhesion related genes among those genes that were unique to each genome. We also found that each isolate has at least one type 3 secretion system (T3SS, a known virulence factor, though not all identified T3SS belong to the same family nor are they in syntenic genomic locations. Conclusions The Providencia species examined here are characterized by high degree of genomic similarity which will likely extend to other species and isolates within this genus. The presence of T3SS islands in all of the genomes reveal that their presence is not sufficient to indicate virulence towards D. melanogaster, since some of the T3SS-bearing isolates are known to cause little mortality. The variation in adhesion genes and the presence of T3SSs indicates that host cell adhesion is likely an important aspect of Providencia virulence.

  2. Comparative analysis of the radish genome based on a conserved ortholog set (COS) of Brassica.

    Science.gov (United States)

    Jeong, Young-Min; Chung, Won-Hyong; Chung, Hee; Kim, Namshin; Park, Beom-Seok; Lim, Ki-Byung; Yu, Hee-Ju; Mun, Jeong-Hwan

    2014-09-01

    This manuscript provides a Brassica conserved ortholog set (COS) that can be used as diagnostic cross-species markers as well as tools for genetic mapping and genome comparison of the Brassicaceae. A conserved ortholog set (COS) is a collection of genes that are conserved in both sequence and copy number between closely related genomes. COS is a useful resource for developing gene-based markers and is suitable for comparative genome mapping. We developed a COS for Brassica based on proteome comparisons of Arabidopsis thaliana, B. rapa, and B. oleracea to establish a basis for comparative genome analysis of crop species in the Brassicaceae. A total of 1,194 conserved orthologous single-copy genes were identified from the genomes based on whole-genome BLASTP analysis. Gene ontology analysis showed that most of them encoded proteins with unknown function and chloroplast-related genes were enriched. In addition, 152 Brassica COS primer sets were applied to 16 crop and wild species of the Brassicaceae and 57.9-92.8 % of them were successfully amplified across the species representing that a Brassica COS can be used as diagnostic cross-species markers of diverse Brassica species. We constructed a genetic map of Raphanus sativus by analyzing the segregation of 322 COS genes in an F2 population (93 individuals) of Korean cultivars (WK10039 × WK10024). Comparative genome analysis based on the COS genes showed conserved genome structures between R. sativus and B. rapa with lineage-specific rearrangement and fractionation of triplicated subgenome blocks indicating close evolutionary relationship and differentiation of the genomes. The Brassica COS developed in this study will play an important role in genetic, genomic, and breeding studies of crop Brassicaceae species.

  3. Comparative genomics and stx phage characterization of LEE-negative Shiga toxin-producing Escherichia coli

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    Susan Renee Steyert

    2012-11-01

    Full Text Available Infection by Escherichia coli and Shigella species are among the leading causes of death due to diarrheal disease in the world. Shiga toxin producing Escherichia coli (STEC that do not encode the locus of enterocyte effacement (LEE-negative STEC often possess Shiga toxin gene variants and have been isolated from humans and a variety of animal sources. In this study, we compare the genomes of nine LEE-negative STEC harboring various stx alleles with four complete reference LEE-positive STEC isolates. Compared to a representative collection of prototype E. coli and Shigella isolates representing each of the pathotypes, the whole genome phylogeny demonstrated that these isolates are diverse. Whole genome comparative analysis of the 13 genomes revealed that in addition to the absence of the LEE pathogenicity island, phage encoded genes including non-LEE encoded effectors, were absent from all nine LEE-negative STEC genomes. Several plasmid-encoded virulence factors reportedly identified in LEE-negative STEC isolates were identified in only a subset of the nine LEE-negative isolates further confirming the diversity of this group. In combination with whole genome analysis, we characterized the lambdoid phages harboring the various stx alleles and determined their genomic insertion sites. Although the integrase gene sequence corresponded with genomic location, it was not correlated with stx variant, further highlighting the mosaic nature of these phages. The transcription of these phages in different genomic backgrounds was examined. Expression of the Shiga toxin genes, stx1 and/or stx2, as well as the Q genes, were examined with quantitative reverse transcriptase polymerase chain reaction (qRT-PCR assays. A wide range of basal and induced toxin induction was observed. Overall, this is a first significant foray into the genome space of this unexplored group of emerging and divergent pathogens.

  4. Cost-effective cloud computing: a case study using the comparative genomics tool, roundup.

    Science.gov (United States)

    Kudtarkar, Parul; Deluca, Todd F; Fusaro, Vincent A; Tonellato, Peter J; Wall, Dennis P

    2010-12-22

    Comparative genomics resources, such as ortholog detection tools and repositories are rapidly increasing in scale and complexity. Cloud computing is an emerging technological paradigm that enables researchers to dynamically build a dedicated virtual cluster and may represent a valuable alternative for large computational tools in bioinformatics. In the present manuscript, we optimize the computation of a large-scale comparative genomics resource-Roundup-using cloud computing, describe the proper operating principles required to achieve computational efficiency on the cloud, and detail important procedures for improving cost-effectiveness to ensure maximal computation at minimal costs. Utilizing the comparative genomics tool, Roundup, as a case study, we computed orthologs among 902 fully sequenced genomes on Amazon's Elastic Compute Cloud. For managing the ortholog processes, we designed a strategy to deploy the web service, Elastic MapReduce, and maximize the use of the cloud while simultaneously minimizing costs. Specifically, we created a model to estimate cloud runtime based on the size and complexity of the genomes being compared that determines in advance the optimal order of the jobs to be submitted. We computed orthologous relationships for 245,323 genome-to-genome comparisons on Amazon's computing cloud, a computation that required just over 200 hours and cost $8,000 USD, at least 40% less than expected under a strategy in which genome comparisons were submitted to the cloud randomly with respect to runtime. Our cost savings projections were based on a model that not only demonstrates the optimal strategy for deploying RSD to the cloud, but also finds the optimal cluster size to minimize waste and maximize usage. Our cost-reduction model is readily adaptable for other comparative genomics tools and potentially of significant benefit to labs seeking to take advantage of the cloud as an alternative to local computing infrastructure.

  5. Comparative analysis of CRISPR-Cas systems in Klebsiella genomes.

    Science.gov (United States)

    Shen, Juntao; Lv, Li; Wang, Xudong; Xiu, Zhilong; Chen, Guoqiang

    2017-04-01

    Prokaryotic CRISPR-Cas system provides adaptive immunity against invasive genetic elements. Bacteria of the genus Klebsiella are important nosocomial opportunistic pathogens. However, information of CRISPR-Cas system in Klebsiella remains largely unknown. Here, we analyzed the CRISPR-Cas systems of 68 complete genomes of Klebsiella representing four species. All the elements for CRISPR-Cas system (cas genes, repeats, leader sequences, and PAMs) were characterized. Besides the typical Type I-E and I-F CRISPR-Cas systems, a new Subtype I system located in the ABC transport system-glyoxalase region was found. The conservation of the new subtype CRISPR system between different species showed new evidence for CRISPR horizontal transfer. CRISPR polymorphism was strongly correlated both with species and multilocus sequence types. Some results indicated the function of adaptive immunity: most spacers (112 of 124) matched to prophages and plasmids and no matching housekeeping genes; new spacer acquisition was observed within the same sequence type (ST) and same clonal complex; the identical spacers were observed only in the ancient position (far from the leader) between different STs and clonal complexes. Interestingly, a high ratio of self-targeting spacers (7.5%, 31 of 416) was found in CRISPR-bearing Klebsiella pneumoniae (61%, 11 of 18). In some strains, there even were multiple full matching self-targeting spacers. Some self-targeting spacers were conserved even between different STs. These results indicated that some unknown mechanisms existed to compromise the function of self-targets of CRISPR-Cas systems in K. pneumoniae. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. The mitochondrial genome of the ascalaphid owlfly Libelloides macaronius and comparative evolutionary mitochondriomics of neuropterid insects

    Science.gov (United States)

    2011-01-01

    Background The insect order Neuroptera encompasses more than 5,700 described species. To date, only three neuropteran mitochondrial genomes have been fully and one partly sequenced. Current knowledge on neuropteran mitochondrial genomes is limited, and new data are strongly required. In the present work, the mitochondrial genome of the ascalaphid owlfly Libelloides macaronius is described and compared with the known neuropterid mitochondrial genomes: Megaloptera, Neuroptera and Raphidioptera. These analyses are further extended to other endopterygotan orders. Results The mitochondrial genome of L. macaronius is a circular molecule 15,890 bp long. It includes the entire set of 37 genes usually present in animal mitochondrial genomes. The gene order of this newly sequenced genome is unique among Neuroptera and differs from the ancestral type of insects in the translocation of trnC. The L. macaronius genome shows the lowest A+T content (74.50%) among known neuropterid genomes. Protein-coding genes possess the typical mitochondrial start codons, except for cox1, which has an unusual ACG. Comparisons among endopterygotan mitochondrial genomes showed that A+T content and AT/GC-skews exhibit a broad range of variation among 84 analyzed taxa. Comparative analyses showed that neuropterid mitochondrial protein-coding genes experienced complex evolutionary histories, involving features ranging from codon usage to rate of substitution, that make them potential markers for population genetics/phylogenetics studies at different taxonomic ranks. The 22 tRNAs show variable substitution patterns in Neuropterida, with higher sequence conservation in genes located on the α strand. Inferred secondary structures for neuropterid rrnS and rrnL genes largely agree with those known for other insects. For the first time, a model is provided for domain I of an insect rrnL. The control region in Neuropterida, as in other insects, is fast-evolving genomic region, characterized by AT

  7. Genomic signature-based identification of influenza A viruses using RT-PCR/electro-spray ionization mass spectrometry (ESI-MS technology.

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    Varough M Deyde

    Full Text Available BACKGROUND: The emergence and rapid spread of the 2009 H1N1 pandemic influenza A virus (H1N1pdm in humans highlights the importance of enhancing the capability of existing influenza surveillance systems with tools for rapid identification of emerging and re-emerging viruses. One of the new approaches is the RT-PCR electrospray ionization mass spectrometry (RT-PCR/ESI-MS technology, which is based on analysis of base composition (BC of RT-PCR amplicons from influenza "core" genes. Combination of the BC signatures represents a "genomic print" of an influenza A virus. METHODOLOGY/PRINCIPAL FINDINGS: Here, 757 samples collected between 2006 and 2009 were tested, including 302 seasonal H1N1, 171 H3N2, 7 swine triple reassortants, and 277 H1N1pdm viruses. Of the 277 H1N1pdm samples, 209 were clinical specimens (throat, nasal and nasopharyngeal swabs, nasal washes, blood and sputum. BC signatures for the clinical specimen from one of the first cases of the 2009 pandemic, A/California/04/2009, confirmed it as an unusual, previously unrecognized influenza A virus, with "core" genes related to viruses of avian, human and swine origins. Subsequent analysis of additional 276 H1N1pdm samples revealed that they shared the genomic print of A/California/04/2009, which differed from those of North American swine triple reassortant viruses, seasonal H1N1 and H3N2 and other viruses tested. Moreover, this assay allowed distinction between "core" genes of co-circulating groups of seasonal H1N1, such as clades 2B, 2C, and their reassortants with dual antiviral resistance to adamantanes and oseltamivir. CONCLUSIONS/SIGNIFICANCE: The RT-PCR/ESI-MS assay is a broad range influenza identification tool that can be used directly on clinical specimens for rapid and accurate detection of influenza virus genes. The assay differentiates the H1N1pdm from seasonal and other nonhuman hosts viruses. Although not a diagnostic tool, this assay demonstrates its usefulness and

  8. Soybean (Glycine max) SWEET gene family: insights through comparative genomics, transcriptome profiling and whole genome re-sequence analysis.

    Science.gov (United States)

    Patil, Gunvant; Valliyodan, Babu; Deshmukh, Rupesh; Prince, Silvas; Nicander, Bjorn; Zhao, Mingzhe; Sonah, Humira; Song, Li; Lin, Li; Chaudhary, Juhi; Liu, Yang; Joshi, Trupti; Xu, Dong; Nguyen, Henry T

    2015-07-11

    SWEET (MtN3_saliva) domain proteins, a recently identified group of efflux transporters, play an indispensable role in sugar efflux, phloem loading, plant-pathogen interaction and reproductive tissue development. The SWEET gene family is predominantly studied in Arabidopsis and members of the family are being investigated in rice. To date, no transcriptome or genomics analysis of soybean SWEET genes has been reported. In the present investigation, we explored the evolutionary aspect of the SWEET gene family in diverse plant species including primitive single cell algae to angiosperms with a major emphasis on Glycine max. Evolutionary features showed expansion and duplication of the SWEET gene family in land plants. Homology searches with BLAST tools and Hidden Markov Model-directed sequence alignments identified 52 SWEET genes that were mapped to 15 chromosomes in the soybean genome as tandem duplication events. Soybean SWEET (GmSWEET) genes showed a wide range of expression profiles in different tissues and developmental stages. Analysis of public transcriptome data and expression profiling using quantitative real time PCR (qRT-PCR) showed that a majority of the GmSWEET genes were confined to reproductive tissue development. Several natural genetic variants (non-synonymous SNPs, premature stop codons and haplotype) were identified in the GmSWEET genes using whole genome re-sequencing data analysis of 106 soybean genotypes. A significant association was observed between SNP-haplogroup and seed sucrose content in three gene clusters on chromosome 6. Present investigation utilized comparative genomics, transcriptome profiling and whole genome re-sequencing approaches and provided a systematic description of soybean SWEET genes and identified putative candidates with probable roles in the reproductive tissue development. Gene expression profiling at different developmental stages and genomic variation data will aid as an important resource for the soybean research

  9. Comparative genomic assessment of Multi-Locus Sequence Typing: rapid accumulation of genomic heterogeneity among clonal isolates of Campylobacter jejuni

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    Nash John HE

    2008-08-01

    Full Text Available Abstract Background Multi-Locus Sequence Typing (MLST has emerged as a leading molecular typing method owing to its high ability to discriminate among bacterial isolates, the relative ease with which data acquisition and analysis can be standardized, and the high portability of the resulting sequence data. While MLST has been successfully applied to the study of the population structure for a number of different bacterial species, it has also provided compelling evidence for high rates of recombination in some species. We have analyzed a set of Campylobacter jejuni strains using MLST and Comparative Genomic Hybridization (CGH on a full-genome microarray in order to determine whether recombination and high levels of genomic mosaicism adversely affect the inference of strain relationships based on the analysis of a restricted number of genetic loci. Results Our results indicate that, in general, there is significant concordance between strain relationships established by MLST and those based on shared gene content as established by CGH. While MLST has significant predictive power with respect to overall genome similarity of isolates, we also found evidence for significant differences in genomic content among strains that would otherwise appear to be highly related based on their MLST profiles. Conclusion The extensive genomic mosaicism between closely related strains has important implications in the context of establishing strain to strain relationships because it suggests that the exact gene content of strains, and by extension their phenotype, is less likely to be "predicted" based on a small number of typing loci. This in turn suggests that a greater emphasis should be placed on analyzing genes of clinical interest as we forge ahead with the next generation of molecular typing methods.

  10. Unique proteomic signature for radiation sensitive patients; a comparative study between normo-sensitive and radiation sensitive breast cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Skiöld, Sara [Center for Radiation Protection Research, Department of Molecular Biosciences, The Wernner-Gren Institute, Stockholm University, Stockholm (Sweden); Azimzadeh, Omid [Institute of Radiation Biology, German Research Center for Environmental Health, Helmholtz Zentrum München (Germany); Merl-Pham, Juliane [Research Unit Protein Science, German Research Center for Environmental Health, Helmholtz Zentrum München, Neuherberg (Germany); Naslund, Ingemar; Wersall, Peter; Lidbrink, Elisabet [Division of Radiotherapy, Radiumhemmet, Karolinska University Hospital, Stockholm (Sweden); Tapio, Soile [Institute of Radiation Biology, German Research Center for Environmental Health, Helmholtz Zentrum München (Germany); Harms-Ringdahl, Mats [Center for Radiation Protection Research, Department of Molecular Biosciences, The Wernner-Gren Institute, Stockholm University, Stockholm (Sweden); Haghdoost, Siamak, E-mail: Siamak.Haghdoost@su.se [Center for Radiation Protection Research, Department of Molecular Biosciences, The Wernner-Gren Institute, Stockholm University, Stockholm (Sweden)

    2015-06-15

    Highlights: • The unique protein expression profiles were found that separate radiosensitive from normal sensitive breast cancer patients. • The oxidative stress response, coagulation properties and acute phase response suggested to be the hallmarks of radiation sensitivity. - Abstract: Radiation therapy is a cornerstone of modern cancer treatment. Understanding the mechanisms behind normal tissue sensitivity is essential in order to minimize adverse side effects and yet to prevent local cancer reoccurrence. The aim of this study was to identify biomarkers of radiation sensitivity to enable personalized cancer treatment. To investigate the mechanisms behind radiation sensitivity a pilot study was made where eight radiation-sensitive and nine normo-sensitive patients were selected from a cohort of 2914 breast cancer patients, based on acute tissue reactions after radiation therapy. Whole blood was sampled and irradiated in vitro with 0, 1, or 150 mGy followed by 3 h incubation at 37 °C. The leukocytes of the two groups were isolated, pooled and protein expression profiles were investigated using isotope-coded protein labeling method (ICPL). First, leukocytes from the in vitro irradiated whole blood from normo-sensitive and extremely sensitive patients were compared to the non-irradiated controls. To validate this first study a second ICPL analysis comparing only the non-irradiated samples was conducted. Both approaches showed unique proteomic signatures separating the two groups at the basal level and after doses of 1 and 150 mGy. Pathway analyses of both proteomic approaches suggest that oxidative stress response, coagulation properties and acute phase response are hallmarks of radiation sensitivity supporting our previous study on oxidative stress response. This investigation provides unique characteristics of radiation sensitivity essential for individualized radiation therapy.

  11. Genome-wide sequencing of cellular microRNAs identifies a combinatorial expression signature diagnostic of sepsis.

    Directory of Open Access Journals (Sweden)

    Yuqian Ma

    Full Text Available Sepsis is a common cause of death in the intensive care unit with mortality up to 70% when accompanied by multiple organ dysfunction. Rapid diagnosis and the institution of appropriate antibiotic therapy and pressor support are therefore critical for survival. MicroRNAs are small non-coding RNAs that play an important role in the regulation of numerous cellular processes, including inflammation and immunity.We hypothesized changes in expression of microRNAs during sepsis may be of diagnostic value in the intensive care unit (ICU.Massively parallel sequencing of microRNAs was utilised for screening microRNA candidates. Putative microRNAs were validated using quantitative real-time PCR (qRT-PCR. This study includes data from both a training cohort (UK and an independent validation cohort (Sweden. A linear discriminant statistical model was employed to construct a diagnostic microRNA signature.A panel of known and novel microRNAs were detectable in the blood of patients with sepsis. After qRT-PCR validation, microRNA miR-150 and miR-4772-5p-iso were able to discriminate between patients who have systemic inflammatory response syndrome and patients with sepsis. This finding was also validated in independent cohort with an average diagnostic accuracy of 86%. Fractionating the cellular components of blood reveals miR-4772-5p-iso is expressed differentially in monocytes. Functional experiments using primary human monocytes demonstrate that it expressed in response to TLR ligation.Taken together, these data provide a novel microRNA signature of sepsis that should allow rapid point-of-care diagnostic assessment of patients on ICU and also provide greater insight into the pathobiology of this severe disease.

  12. Genome-wide sequencing of cellular microRNAs identifies a combinatorial expression signature diagnostic of sepsis.

    Science.gov (United States)

    Ma, Yuqian; Vilanova, David; Atalar, Kerem; Delfour, Olivier; Edgeworth, Jonathan; Ostermann, Marlies; Hernandez-Fuentes, Maria; Razafimahatratra, Sandrine; Michot, Bernard; Persing, David H; Ziegler, Ingrid; Törös, Bianca; Mölling, Paula; Olcén, Per; Beale, Richard; Lord, Graham M

    2013-01-01

    Sepsis is a common cause of death in the intensive care unit with mortality up to 70% when accompanied by multiple organ dysfunction. Rapid diagnosis and the institution of appropriate antibiotic therapy and pressor support are therefore critical for survival. MicroRNAs are small non-coding RNAs that play an important role in the regulation of numerous cellular processes, including inflammation and immunity. We hypothesized changes in expression of microRNAs during sepsis may be of diagnostic value in the intensive care unit (ICU). Massively parallel sequencing of microRNAs was utilised for screening microRNA candidates. Putative microRNAs were validated using quantitative real-time PCR (qRT-PCR). This study includes data from both a training cohort (UK) and an independent validation cohort (Sweden). A linear discriminant statistical model was employed to construct a diagnostic microRNA signature. A panel of known and novel microRNAs were detectable in the blood of patients with sepsis. After qRT-PCR validation, microRNA miR-150 and miR-4772-5p-iso were able to discriminate between patients who have systemic inflammatory response syndrome and patients with sepsis. This finding was also validated in independent cohort with an average diagnostic accuracy of 86%. Fractionating the cellular components of blood reveals miR-4772-5p-iso is expressed differentially in monocytes. Functional experiments using primary human monocytes demonstrate that it expressed in response to TLR ligation. Taken together, these data provide a novel microRNA signature of sepsis that should allow rapid point-of-care diagnostic assessment of patients on ICU and also provide greater insight into the pathobiology of this severe disease.

  13. Comparative genomics analyses revealed two virulent Listeria monocytogenes strains isolated from ready-to-eat food.

    Science.gov (United States)

    Lim, Shu Yong; Yap, Kien-Pong; Thong, Kwai Lin

    2016-01-01

    Listeria monocytogenes is an important foodborne pathogen that causes considerable morbidity in humans with high mortality rates. In this study, we have sequenced the genomes and performed comparative genomics analyses on two strains, LM115 and LM41, isolated from ready-to-eat food in Malaysia. The genome size of LM115 and LM41 was 2,959,041 and 2,963,111 bp, respectively. These two strains shared approximately 90% homologous genes. Comparative genomics and phylogenomic analyses revealed that LM115 and LM41 were more closely related to the reference strains F2365 and EGD-e, respectively. Our virulence profiling indicated a total of 31 virulence genes shared by both analysed strains. These shared genes included those that encode for internalins and L. monocytogenes pathogenicity island 1 (LIPI-1). Both the Malaysian L. monocytogenes strains also harboured several genes associated with stress tolerance to counter the adverse conditions. Seven antibiotic and efflux pump related genes which may confer resistance against lincomycin, erythromycin, fosfomycin, quinolone, tetracycline, and penicillin, and macrolides were identified in the genomes of both strains. Whole genome sequencing and comparative genomics analyses revealed two virulent L. monocytogenes strains isolated from ready-to-eat foods in Malaysia. The identification of strains with pathogenic, persistent, and antibiotic resistant potentials from minimally processed food warrant close attention from both healthcare and food industry.

  14. PLAZA 3.0: an access point for plant comparative genomics.

    Science.gov (United States)

    Proost, Sebastian; Van Bel, Michiel; Vaneechoutte, Dries; Van de Peer, Yves; Inzé, Dirk; Mueller-Roeber, Bernd; Vandepoele, Klaas

    2015-01-01

    Comparative sequence analysis has significantly altered our view on the complexity of genome organization and gene functions in different kingdoms. PLAZA 3.0 is designed to make comparative genomics data for plants available through a user-friendly web interface. Structural and functional annotation, gene families, protein domains, phylogenetic trees and detailed information about genome organization can easily be queried and visualized. Compared with the first version released in 2009, which featured nine organisms, the number of integrated genomes is more than four times higher, and now covers 37 plant species. The new species provide a wider phylogenetic range as well as a more in-depth sampling of specific clades, and genomes of additional crop species are present. The functional annotation has been expanded and now comprises data from Gene Ontology, MapMan, UniProtKB/Swiss-Prot, PlnTFDB and PlantTFDB. Furthermore, we improved the algorithms to transfer functional annotation from well-characterized plant genomes to other species. The additional data and new features make PLAZA 3.0 (http://bioinformatics.psb.ugent.be/plaza/) a versatile and comprehensible resource for users wanting to explore genome information to study different aspects of plant biology, both in model and non-model organisms. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. Pan-cancer analysis of genomic scar signatures associated with homologous recombination deficiency suggests novel indications for existing cancer drugs

    DEFF Research Database (Denmark)

    Marquard, Andrea Marion; Eklund, Aron Charles; Joshi, Tejal

    2015-01-01

    Ovarian and triple-negative breast cancers with BRCA1 or BRCA2 loss are highly sensitive to treatment with PARP inhibitors and platinum-based cytotoxic agents and show an accumulation of genomic scars in the form of gross DNA copy number aberrations. Cancers without BRCA1 or BRCA2 loss...... but with accumulation of similar genomic scars also show increased sensitivity to platinum-based chemotherapy. Therefore, reliable biomarkers to identify DNA repair-deficient cancers prior to treatment may be useful for directing patients to platinum chemotherapy and possibly PARP inhibitors. Recently, three SNP array...... may be strong candidates for clinical trials with PARP inhibitors or platinum-based chemotherapeutic regimens....

  16. Fishing in troubled waters: Revealing genomic signatures of local adaptation in response to freshwater pollutants in two macroinvertebrates.

    Science.gov (United States)

    Weigand, Hannah; Weiss, Martina; Cai, Huimin; Li, Yongping; Yu, Lili; Zhang, Christine; Leese, Florian

    2018-03-27

    Local adaptation is of fundamental importance for populations to cope with fast, human-mediated environmental changes. In the past, analyses of local adaptation were restricted to few model species. Nowadays, due to the increased affordability of high-throughput sequencing, local adaptation can be studied much easier by searching for patterns of positive selection using genomic data. In the present study, we analysed effects of wastewater treatment plant and ore mining effluents on stream invertebrate populations. The two different anthropogenic stressors have impacted on stream ecosystems over different time scales and with different potencies. As target organisms we selected two macroinvertebrate species with different life histories and dispersal capacities: the caddisfly Glossosoma conformis and the flatworm Dugesia gonocephala. We applied a genome-wide genetic marker technique, termed ddRAD (double digest restriction site associated DNA) sequencing, to identify local adaptation. Ten and 18% of all loci were identified as candidate loci for local adaptation in D. gonocephala and G. conformis, respectively. However, after stringent re-evaluation of the genomic data, strong evidence for local adaptation remained only for one population of the flatworm D. gonocephala affected by high copper concentration from ore mining. One of the corresponding candidate loci is arnt, a gene associated with the response to xenobiotics and potentially involved in metal detoxification. Our results support the hypotheses that local adaptation is more likely to play a central role in environments impacted by a stronger stressor for a longer time and that it is more likely to occur in species with lower migration rates. However, these findings have to be interpreted cautiously, as several confounding factors may have limited the possibility to detect local adaptation. Our study highlights how genomic tools can be used to study the adaptability and thus resistance of natural

  17. Genomic sequence around butterfly wing development genes: annotation and comparative analysis.

    Directory of Open Access Journals (Sweden)

    Inês C Conceição

    Full Text Available BACKGROUND: Analysis of genomic sequence allows characterization of genome content and organization, and access beyond gene-coding regions for identification of functional elements. BAC libraries, where relatively large genomic regions are made readily available, are especially useful for species without a fully sequenced genome and can increase genomic coverage of phylogenetic and biological diversity. For example, no butterfly genome is yet available despite the unique genetic and biological properties of this group, such as diversified wing color patterns. The evolution and development of these patterns is being studied in a few target species, including Bicyclus anynana, where a whole-genome BAC library allows targeted access to large genomic regions. METHODOLOGY/PRINCIPAL FINDINGS: We characterize ∼1.3 Mb of genomic sequence around 11 selected genes expressed in B. anynana developing wings. Extensive manual curation of in silico predictions, also making use of a large dataset of expressed genes for this species, identified repetitive elements and protein coding sequence, and highlighted an expansion of Alcohol dehydrogenase genes. Comparative analysis with orthologous regions of the lepidopteran reference genome allowed assessment of conservation of fine-scale synteny (with detection of new inversions and translocations and of DNA sequence (with detection of high levels of conservation of non-coding regions around some, but not all, developmental genes. CONCLUSIONS: The general properties and organization of the available B. anynana genomic sequence are similar to the lepidopteran reference, despite the more than 140 MY divergence. Our results lay the groundwork for further studies of new interesting findings in relation to both coding and non-coding sequence: 1 the Alcohol dehydrogenase expansion with higher similarity between the five tandemly-repeated B. anynana paralogs than with the corresponding B. mori orthologs, and 2 the high

  18. Comparative genomics reveals convergent evolution between the bamboo-eating giant and red pandas.

    Science.gov (United States)

    Hu, Yibo; Wu, Qi; Ma, Shuai; Ma, Tianxiao; Shan, Lei; Wang, Xiao; Nie, Yonggang; Ning, Zemin; Yan, Li; Xiu, Yunfang; Wei, Fuwen

    2017-01-31

    Phenotypic convergence between distantly related taxa often mirrors adaptation to similar selective pressures and may be driven by genetic convergence. The giant panda (Ailuropoda melanoleuca) and red panda (Ailurus fulgens) belong to different families in the order Carnivora, but both have evolved a specialized bamboo diet and adaptive pseudothumb, representing a classic model of convergent evolution. However, the genetic bases of these morphological and physiological convergences remain unknown. Through de novo sequencing the red panda genome and improving the giant panda genome assembly with added data, we identified genomic signatures of convergent evolution. Limb development genes DYNC2H1 and PCNT have undergone adaptive convergence and may be important candidate genes for pseudothumb development. As evolutionary responses to a bamboo diet, adaptive convergence has occurred in genes involved in the digestion and utilization of bamboo nutrients such as essential amino acids, fatty acids, and vitamins. Similarly, the umami taste receptor gene TAS1R1 has been pseudogenized in both pandas. These findings offer insights into genetic convergence mechanisms underlying phenotypic convergence and adaptation to a specialized bamboo diet.

  19. Genome-based comparative analyses of Antarctic and temperate species of Paenibacillus.

    Directory of Open Access Journals (Sweden)

    Melissa Dsouza

    Full Text Available Antarctic soils represent a unique environment characterised by extremes of temperature, salinity, elevated UV radiation, low nutrient and low water content. Despite the harshness of this environment, members of 15 bacterial phyla have been identified in soils of the Ross Sea Region (RSR. However, the survival mechanisms and ecological roles of these phyla are largely unknown. The aim of this study was to investigate whether strains of Paenibacillus darwinianus owe their resilience to substantial genomic changes. For this, genome-based comparative analyses were performed on three P. darwinianus strains, isolated from gamma-irradiated RSR soils, together with nine temperate, soil-dwelling Paenibacillus spp. The genome of each strain was sequenced to over 1,000-fold coverage, then assembled into contigs totalling approximately 3 Mbp per genome. Based on the occurrence of essential, single-copy genes, genome completeness was estimated at approximately 88%. Genome analysis revealed between 3,043-3,091 protein-coding sequences (CDSs, primarily associated with two-component systems, sigma factors, transporters, sporulation and genes induced by cold-shock, oxidative and osmotic stresses. These comparative analyses provide an insight into the metabolic potential of P. darwinianus, revealing potential adaptive mechanisms for survival in Antarctic soils. However, a large proportion of these mechanisms were also identified in temperate Paenibacillus spp., suggesting that these mechanisms are beneficial for growth and survival in a range of soil environments. These analyses have also revealed that the P. darwinianus genomes contain significantly fewer CDSs and have a lower paralogous content. Notwithstanding the incompleteness of the assemblies, the large differences in genome sizes, determined by the number of genes in paralogous clusters and the CDS content, are indicative of genome content scaling. Finally, these sequences are a resource for further

  20. Multi-platform whole-genome microarray analyses refine the epigenetic signature of breast cancer metastasis with gene expression and copy number.

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    Joseph Andrews

    Full Text Available BACKGROUND: We have previously identified genome-wide DNA methylation changes in a cell line model of breast cancer metastasis. These complex epigenetic changes that we observed, along with concurrent karyotype analyses, have led us to hypothesize that complex genomic alterations in cancer cells (deletions, translocations and ploidy are superimposed over promoter-specific methylation events that are responsible for gene-specific expression changes observed in breast cancer metastasis. METHODOLOGY/PRINCIPAL FINDINGS: We undertook simultaneous high-resolution, whole-genome analyses of MDA-MB-468GFP and MDA-MB-468GFP-LN human breast cancer cell lines (an isogenic, paired lymphatic metastasis cell line model using Affymetrix gene expression (U133, promoter (1.0R, and SNP/CNV (SNP 6.0 microarray platforms to correlate data from gene expression, epigenetic (DNA methylation, and combination copy number variant/single nucleotide polymorphism microarrays. Using Partek Software and Ingenuity Pathway Analysis we integrated datasets from these three platforms and detected multiple hypomethylation and hypermethylation events. Many of these epigenetic alterations correlated with gene expression changes. In addition, gene dosage events correlated with the karyotypic differences observed between the cell lines and were reflected in specific promoter methylation patterns. Gene subsets were identified that correlated hyper (and hypo methylation with the loss (or gain of gene expression and in parallel, with gene dosage losses and gains, respectively. Individual gene targets from these subsets were also validated for their methylation, expression and copy number status, and susceptible gene pathways were identified that may indicate how selective advantage drives the processes of tumourigenesis and metastasis. CONCLUSIONS/SIGNIFICANCE: Our approach allows more precisely profiling of functionally relevant epigenetic signatures that are associated with cancer

  1. Assessment of signature handwriting evidence via score-based likelihood ratio based on comparative measurement of relevant dynamic features.

    Science.gov (United States)

    Chen, Xiao-Hong; Champod, Christophe; Yang, Xu; Shi, Shao-Pei; Luo, Yi-Wen; Wang, Nan; Wang, Ya-Chen; Lu, Qi-Meng

    2018-01-01