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Sample records for ece-cyc2 clade genes

  1. Divergent regulation of Arabidopsis SAUR genes: a focus on the SAUR10-clade.

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    van Mourik, Hilda; van Dijk, Aalt D J; Stortenbeker, Niek; Angenent, Gerco C; Bemer, Marian

    2017-12-19

    Small Auxin-Upregulated RNA (SAUR) genes encode growth regulators that induce cell elongation. Arabidopsis contains more than 70 SAUR genes, of which the growth-promoting function has been unveiled in seedlings, while their role in other tissues remained largely unknown. Here, we focus on the regulatory regions of Arabidopsis SAUR genes, to predict the processes in which they play a role, and understand the dynamics of plant growth. In this study, we characterized in detail the entire SAUR10-clade: SAUR8, SAUR9, SAUR10, SAUR12, SAUR16, SAUR50, SAUR51 and SAUR54. Overexpression analysis revealed that the different proteins fulfil similar functions, while the SAUR expression patterns were highly diverse, showing expression throughout plant development in a variety of tissues. In addition, the response to application of different hormones largely varied between the different genes. These tissue-specific and hormone-specific responses could be linked to transcription factor binding sites using in silico analyses. These analyses also supported the existence of two groups of SAURs in Arabidopsis: Class I genes can be induced by combinatorial action of ARF-BZR-PIF transcription factors, while Class II genes are not regulated by auxin. SAUR10-clade genes generally induce cell-elongation, but exhibit diverse expression patterns and responses to hormones. Our experimental and in silico analyses suggest that transcription factors involved in plant development determine the tissue specific expression of the different SAUR genes, whereas the amplitude of this expression can often be controlled by hormone response transcription factors. This allows the plant to fine tune growth in a variety of tissues in response to internal and external signals.

  2. Plastid genome evolution across the genus Cuscuta (Convolvulaceae): two clades within subgenus Grammica exhibit extensive gene loss.

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    Braukmann, Thomas; Kuzmina, Maria; Stefanovic, Sasa

    2013-02-01

    The genus Cuscuta (Convolvulaceae, the morning glory family) is one of the most intensely studied lineages of parasitic plants. Whole plastome sequencing of four Cuscuta species has demonstrated changes to both plastid gene content and structure. The presence of photosynthetic genes under purifying selection indicates that Cuscuta is cryptically photosynthetic. However, the tempo and mode of plastid genome evolution across the diversity of this group (~200 species) remain largely unknown. A comparative investigation of plastid genome content, grounded within a phylogenetic framework, was conducted using a slot-blot Southern hybridization approach. Cuscuta was extensively sampled (~56% of species), including groups previously suggested to possess more altered plastomes compared with other members of this genus. A total of 56 probes derived from all categories of protein-coding genes, typically found within the plastomes of flowering plants, were used. The results indicate that two clades within subgenus Grammica (clades 'O' and 'K') exhibit substantially more plastid gene loss relative to other members of Cuscuta. All surveyed members of the 'O' clade show extensive losses of plastid genes from every category of genes typically found in the plastome, including otherwise highly conserved small and large ribosomal subunits. The extent of plastid gene losses within this clade is similar in magnitude to that observed previously in some non-asterid holoparasites, in which the very presence of a plastome has been questioned. The 'K' clade also exhibits considerable loss of plastid genes. Unlike in the 'O' clade, in which all species seem to be affected, the losses in clade 'K' progress phylogenetically, following a pattern consistent with the Evolutionary Transition Series hypothesis. This clade presents an ideal opportunity to study the reduction of the plastome of parasites 'in action'. The widespread plastid gene loss in these two clades is hypothesized to be a

  3. Genes of the most conserved WOX clade in plants affect root and flower development in Arabidopsis

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    Moreau Hervé

    2008-10-01

    Full Text Available Abstract Background The Wuschel related homeobox (WOX family proteins are key regulators implicated in the determination of cell fate in plants by preventing cell differentiation. A recent WOX phylogeny, based on WOX homeodomains, showed that all of the Physcomitrella patens and Selaginella moellendorffii WOX proteins clustered into a single orthologous group. We hypothesized that members of this group might preferentially share a significant part of their function in phylogenetically distant organisms. Hence, we first validated the limits of the WOX13 orthologous group (WOX13 OG using the occurrence of other clade specific signatures and conserved intron insertion sites. Secondly, a functional analysis using expression data and mutants was undertaken. Results The WOX13 OG contained the most conserved plant WOX proteins including the only WOX detected in the highly proliferating basal unicellular and photosynthetic organism Ostreococcus tauri. A large expansion of the WOX family was observed after the separation of mosses from other land plants and before monocots and dicots have arisen. In Arabidopsis thaliana, AtWOX13 was dynamically expressed during primary and lateral root initiation and development, in gynoecium and during embryo development. AtWOX13 appeared to affect the floral transition. An intriguing clade, represented by the functional AtWOX14 gene inside the WOX13 OG, was only found in the Brassicaceae. Compared to AtWOX13, the gene expression profile of AtWOX14 was restricted to the early stages of lateral root formation and specific to developing anthers. A mutational insertion upstream of the AtWOX14 homeodomain sequence led to abnormal root development, a delay in the floral transition and premature anther differentiation. Conclusion Our data provide evidence in favor of the WOX13 OG as the clade containing the most conserved WOX genes and established a functional link to organ initiation and development in Arabidopsis, most

  4. Evolution and functional insights of different ancestral orthologous clades of chitin synthase genes in the fungal tree of life

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    Mu eLi

    2016-02-01

    Full Text Available Chitin synthases (CHSs are key enzymes in the biosynthesis of chitin, an important structural component of fungal cell walls that can trigger innate immune responses in host plants and animals. Members of CHS gene family perform various functions in fungal cellular processes. Previous studies focused primarily on classifying diverse CHSs into different classes, regardless of their functional diversification, or on characterizing their functions in individual fungal species. A complete and systematic comparative analysis of CHS genes based on their orthologous relationships will be valuable for elucidating the evolution and functions of different CHS genes in fungi. Here, we identified and compared members of the CHS gene family across the fungal tree of life, including 18 divergent fungal lineages. Phylogenetic analysis revealed that the fungal CHS gene family is comprised of at least 10 ancestral orthologous clades, which have undergone multiple independent duplications and losses in different fungal lineages during evolution. Interestingly, one of these CHS clades (class III was expanded in plant or animal pathogenic fungi belonging to different fungal lineages. Two clades (classes VIb and VIc identified for the first time in this study occurred mainly in plant pathogenic fungi from Sordariomycetes and Dothideomycetes. Moreover, members of classes III and VIb were specifically up-regulated during plant infection, suggesting important roles in pathogenesis. In addition, CHS-associated networks conserved among plant pathogenic fungi are involved in various biological processes, including sexual reproduction and plant infection. We also identified specificity-determining sites, many of which are located at or adjacent to important structural and functional sites that are potentially responsible for functional divergence of different CHS classes. Overall, our results provide new insights into the evolution and function of members of CHS gene

  5. A clade-specific Arabidopsis gene connects primary metabolism and senescence

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    Plants have to deal with environmental insults as they cannot move to escape from stressful conditions. To do so, they have evolved novel components that respond to the changing environments. A primary example is Qua Quine Starch (QQS, AT3G30720), an Arabidopsis thaliana-specific (orphan) gene that ...

  6. SOLiD sequencing of four Vibrio vulnificus genomes enables comparative genomic analysis and identification of candidate clade-specific virulence genes

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    Telonis-Scott Marina

    2010-09-01

    Full Text Available Abstract Background Vibrio vulnificus is the leading cause of reported death from consumption of seafood in the United States. Despite several decades of research on molecular pathogenesis, much remains to be learned about the mechanisms of virulence of this opportunistic bacterial pathogen. The two complete and annotated genomic DNA sequences of V. vulnificus belong to strains of clade 2, which is the predominant clade among clinical strains. Clade 2 strains generally possess higher virulence potential in animal models of disease compared with clade 1, which predominates among environmental strains. SOLiD sequencing of four V. vulnificus strains representing different clades (1 and 2 and biotypes (1 and 2 was used for comparative genomic analysis. Results Greater than 4,100,000 bases were sequenced of each strain, yielding approximately 100-fold coverage for each of the four genomes. Although the read lengths of SOLiD genomic sequencing were only 35 nt, we were able to make significant conclusions about the unique and shared sequences among the genomes, including identification of single nucleotide polymorphisms. Comparative analysis of the newly sequenced genomes to the existing reference genomes enabled the identification of 3,459 core V. vulnificus genes shared among all six strains and 80 clade 2-specific genes. We identified 523,161 SNPs among the six genomes. Conclusions We were able to glean much information about the genomic content of each strain using next generation sequencing. Flp pili, GGDEF proteins, and genomic island XII were identified as possible virulence factors because of their presence in virulent sequenced strains. Genomic comparisons also point toward the involvement of sialic acid catabolism in pathogenesis.

  7. Cowpea and peanut in southern Africa are nodulated by diverse Bradyrhizobium strains harboring nodulation genes that belong to the large pantropical clade common in Africa.

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    Steenkamp, Emma T; Stepkowski, Tomasz; Przymusiak, Anna; Botha, Wilhelm J; Law, Ian J

    2008-09-01

    Cowpea (Vigna unguiculata) and peanut (Arachis hypogaea) in southern Africa are nodulated by a genetically diverse group of Bradyrhizobium strains. To determine the identity of these bacteria, a collection of 22 isolates originating from the root nodules of both hosts in Botswana and South Africa was investigated using the combined sequences for the core genome genes rrs, recA, and glnII. These data separated the majority of the isolates into one of three unique lineages that most likely represent novel Bradyrhizobium species. Some isolates were also conspecific with B. yuanmingense and with B. elkanii, although none grouped with B. japonicum, B. canariense or B. liaoningense. To study the evolution of nodulation genes in these bacteria, the common nodulation gene, nodA, and host-specific nodulation genes, nodZ, noeE, and noeI, were analyzed. The nodA phylogeny showed that the cowpea and peanut Bradyrhizobium isolates represent various locally adapted groups or ecotypes that form part of Clade III of the seven known BradyrhizobiumnodA clades. This large and highly diverse clade comprises all strains from sub-Saharan Africa, as well as some originating from the Americas, Australia, Indonesia, China and Japan. Some similar groupings were supported by the other nodulation genes, although the overall phylogenies for the nodulation genes were incongruent with that inferred from the core genome genes, suggesting that horizontal gene transfer significantly influences the evolution of cowpea and peanut root-nodule bacteria. Furthermore, identification of the nodZ, noeI, and noeE genes in the isolates tested indicates that African Bradyrhizobium species may produce highly decorated nodulation factors, which potentially represent an important adaptation enabling nodulation of a great variety of legumes inhabiting the African continent.

  8. Analysis of the grape MYB R2R3 subfamily reveals expanded wine quality-related clades and conserved gene structure organization across Vitis and Arabidopsis genomes

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    Matus, José Tomás; Aquea, Felipe; Arce-Johnson, Patricio

    2008-01-01

    Background The MYB superfamily constitutes the most abundant group of transcription factors described in plants. Members control processes such as epidermal cell differentiation, stomatal aperture, flavonoid synthesis, cold and drought tolerance and pathogen resistance. No genome-wide characterization of this family has been conducted in a woody species such as grapevine. In addition, previous analysis of the recently released grape genome sequence suggested expansion events of several gene families involved in wine quality. Results We describe and classify 108 members of the grape R2R3 MYB gene subfamily in terms of their genomic gene structures and similarity to their putative Arabidopsis thaliana orthologues. Seven gene models were derived and analyzed in terms of gene expression and their DNA binding domain structures. Despite low overall sequence homology in the C-terminus of all proteins, even in those with similar functions across Arabidopsis and Vitis, highly conserved motif sequences and exon lengths were found. The grape epidermal cell fate clade is expanded when compared with the Arabidopsis and rice MYB subfamilies. Two anthocyanin MYBA related clusters were identified in chromosomes 2 and 14, one of which includes the previously described grape colour locus. Tannin related loci were also detected with eight candidate homologues in chromosomes 4, 9 and 11. Conclusion This genome wide transcription factor analysis in Vitis suggests that clade-specific grape R2R3 MYB genes are expanded while other MYB genes could be well conserved compared to Arabidopsis. MYB gene abundance, homology and orientation within particular loci also suggests that expanded MYB clades conferring quality attributes of grapes and wines, such as colour and astringency, could possess redundant, overlapping and cooperative functions. PMID:18647406

  9. Analysis of the grape MYB R2R3 subfamily reveals expanded wine quality-related clades and conserved gene structure organization across Vitis and Arabidopsis genomes

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    Arce-Johnson Patricio

    2008-07-01

    Full Text Available Abstract Background The MYB superfamily constitutes the most abundant group of transcription factors described in plants. Members control processes such as epidermal cell differentiation, stomatal aperture, flavonoid synthesis, cold and drought tolerance and pathogen resistance. No genome-wide characterization of this family has been conducted in a woody species such as grapevine. In addition, previous analysis of the recently released grape genome sequence suggested expansion events of several gene families involved in wine quality. Results We describe and classify 108 members of the grape R2R3 MYB gene subfamily in terms of their genomic gene structures and similarity to their putative Arabidopsis thaliana orthologues. Seven gene models were derived and analyzed in terms of gene expression and their DNA binding domain structures. Despite low overall sequence homology in the C-terminus of all proteins, even in those with similar functions across Arabidopsis and Vitis, highly conserved motif sequences and exon lengths were found. The grape epidermal cell fate clade is expanded when compared with the Arabidopsis and rice MYB subfamilies. Two anthocyanin MYBA related clusters were identified in chromosomes 2 and 14, one of which includes the previously described grape colour locus. Tannin related loci were also detected with eight candidate homologues in chromosomes 4, 9 and 11. Conclusion This genome wide transcription factor analysis in Vitis suggests that clade-specific grape R2R3 MYB genes are expanded while other MYB genes could be well conserved compared to Arabidopsis. MYB gene abundance, homology and orientation within particular loci also suggests that expanded MYB clades conferring quality attributes of grapes and wines, such as colour and astringency, could possess redundant, overlapping and cooperative functions.

  10. Genetic recombination events between sympatric Clade A and Clade C lice in Africa.

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    Veracx, Aurélie; Boutellis, Amina; Raoult, Didier

    2013-09-01

    Human head and body lice have been classified into three phylogenetic clades (Clades A, B, and C) based on mitochondrial DNA. Based on nuclear markers (the 18S rRNA gene and the PM2 spacer), two genotypes of Clade A head and body lice, including one that is specifically African (Clade A2), have been described. In this study, we sequenced the PM2 spacer of Clade C head lice from Ethiopia and compared these sequences with sequences from previous works. Trees were drawn, and an analysis of genetic diversity based on the cytochrome b gene and the PM2 spacer was performed for African and non-African lice. In the tree drawn based on the PM2 spacer, the African and non-African lice formed separate clusters. However, Clade C lice from Ethiopia were placed within the African Clade A subcluster (Clade A2). This result suggests that recombination events have occurred between Clade A2 lice and Clade C lice, reflecting the sympatric nature of African lice. Finally, the PM2 spacer and cytochrome b gene sequences of human lice revealed a higher level of genetic diversity in Africa than in other regions.

  11. Strigolactone Levels in Dicot Roots Are Determined by an Ancestral Symbiosis-Regulated Clade of the PHYTOENE SYNTHASE Gene Family

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    Ron Stauder

    2018-03-01

    Full Text Available Strigolactones (SLs are apocarotenoid phytohormones synthesized from carotenoid precursors. They are produced most abundantly in roots for exudation into the rhizosphere to cope with mineral nutrient starvation through support of root symbionts. Abscisic acid (ABA is another apocarotenoid phytohormone synthesized in roots, which is involved in responses to abiotic stress. Typically low carotenoid levels in roots raise the issue of precursor supply for the biosynthesis of these two apocarotenoids in this organ. Increased ABA levels upon abiotic stress in Poaceae roots are known to be supported by a particular isoform of phytoene synthase (PSY, catalyzing the rate-limiting step in carotenogenesis. Here we report on novel PSY3 isogenes from Medicago truncatula (MtPSY3 and Solanum lycopersicum (SlPSY3 strongly expressed exclusively upon root interaction with symbiotic arbuscular mycorrhizal (AM fungi and moderately in response to phosphate starvation. They belong to a widespread clade of conserved PSYs restricted to dicots (dPSY3 distinct from the Poaceae-PSY3s involved in ABA formation. An ancient origin of dPSY3s and a potential co-evolution with the AM symbiosis is discussed in the context of PSY evolution. Knockdown of MtPSY3 in hairy roots of M. truncatula strongly reduced SL and AM-induced C13 α-ionol/C14 mycorradicin apocarotenoids. Inhibition of the reaction subsequent to phytoene synthesis revealed strongly elevated levels of phytoene indicating induced flux through the carotenoid pathway in roots upon mycorrhization. dPSY3 isogenes are coregulated with upstream isogenes and downstream carotenoid cleavage steps toward SLs (D27, CCD7, CCD8 suggesting a combined carotenoid/apocarotenoid pathway, which provides “just in time”-delivery of precursors for apocarotenoid formation.

  12. Functional diversification of duplicated CYC2 clade genes in regulation of inflorescence development in Gerbera hybrida (Asteraceae).

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    Juntheikki-Palovaara, Inka; Tähtiharju, Sari; Lan, Tianying; Broholm, Suvi K; Rijpkema, Anneke S; Ruonala, Raili; Kale, Liga; Albert, Victor A; Teeri, Teemu H; Elomaa, Paula

    2014-09-01

    The complex inflorescences (capitula) of Asteraceae consist of different types of flowers. In Gerbera hybrida (gerbera), the peripheral ray flowers are bilaterally symmetrical and lack functional stamens while the central disc flowers are more radially symmetrical and hermaphroditic. Proteins of the CYC2 subclade of the CYC/TB1-like TCP domain transcription factors have been recruited several times independently for parallel evolution of bilaterally symmetrical flowers in various angiosperm plant lineages, and have also been shown to regulate flower-type identity in Asteraceae. The CYC2 subclade genes in gerbera show largely overlapping gene expression patterns. At the level of single flowers, their expression domain in petals shows a spatial shift from the dorsal pattern known so far in species with bilaterally symmetrical flowers, suggesting that this change in expression may have evolved after the origin of Asteraceae. Functional analysis indicates that GhCYC2, GhCYC3 and GhCYC4 mediate positional information at the proximal-distal axis of the inflorescence, leading to differentiation of ray flowers, but that they also regulate ray flower petal growth by affecting cell proliferation until the final size and shape of the petals is reached. Moreover, our data show functional diversification for the GhCYC5 gene. Ectopic activation of GhCYC5 increases flower density in the inflorescence, suggesting that GhCYC5 may promote the flower initiation rate during expansion of the capitulum. Our data thus indicate that modification of the ancestral network of TCP factors has, through gene duplications, led to the establishment of new expression domains and to functional diversification. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  13. Fate of a redundant gamma-globin gene in the atelid clade of New World monkeys: implications concerning fetal globin gene expression.

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    Meireles, C M; Schneider, M P; Sampaio, M I; Schneider, H; Slightom, J L; Chiu, C H; Neiswanger, K; Gumucio, D L; Czelusniak, J; Goodman, M

    1995-01-01

    Conclusive evidence was provided that gamma 1, the upstream of the two linked simian gamma-globin loci (5'-gamma 1-gamma 2-3'), is a pseudogene in a major group of New World monkeys. Sequence analysis of PCR-amplified genomic fragments of predicted sizes revealed that all extant genera of the platyrrhine family Atelidae [Lagothrix (woolly monkeys), Brachyteles (woolly spider monkeys), Ateles (spider monkeys), and Alouatta (howler monkeys)] share a large deletion that removed most of exon 2, all of intron 2 and exon 3, and much of the 3' flanking sequence of gamma 1. The fact that two functional gamma-globin genes were not present in early ancestors of the Atelidae (and that gamma 1 was the dispensible gene) suggests that for much or even all of their evolution, platyrrhines have had gamma 2 as the primary fetally expressed gamma-globin gene, in contrast to catarrhines (e.g., humans and chimpanzees) that have gamma 1 as the primary fetally expressed gamma-globin gene. Results from promoter sequences further suggest that all three platyrrhine families (Atelidae, Cebidae, and Pitheciidae) have gamma 2 rather than gamma 1 as their primary fetally expressed gamma-globin gene. The implications of this suggestion were explored in terms of how gene redundancy, regulatory mutations, and distance of each gamma-globin gene from the locus control region were possibly involved in the acquisition and maintenance of fetal, rather than embryonic, expression. Images Fig. 2 PMID:7535927

  14. Targeted Enrichment of Large Gene Families for Phylogenetic Inference: Phylogeny and Molecular Evolution of Photosynthesis Genes in the Portullugo Clade (Caryophyllales).

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    Moore, Abigail J; Vos, Jurriaan M De; Hancock, Lillian P; Goolsby, Eric; Edwards, Erika J

    2018-05-01

    Hybrid enrichment is an increasingly popular approach for obtaining hundreds of loci for phylogenetic analysis across many taxa quickly and cheaply. The genes targeted for sequencing are typically single-copy loci, which facilitate a more straightforward sequence assembly and homology assignment process. However, this approach limits the inclusion of most genes of functional interest, which often belong to multi-gene families. Here, we demonstrate the feasibility of including large gene families in hybrid enrichment protocols for phylogeny reconstruction and subsequent analyses of molecular evolution, using a new set of bait sequences designed for the "portullugo" (Caryophyllales), a moderately sized lineage of flowering plants (~ 2200 species) that includes the cacti and harbors many evolutionary transitions to C$_{\\mathrm{4}}$ and CAM photosynthesis. Including multi-gene families allowed us to simultaneously infer a robust phylogeny and construct a dense sampling of sequences for a major enzyme of C$_{\\mathrm{4}}$ and CAM photosynthesis, which revealed the accumulation of adaptive amino acid substitutions associated with C$_{\\mathrm{4}}$ and CAM origins in particular paralogs. Our final set of matrices for phylogenetic analyses included 75-218 loci across 74 taxa, with ~ 50% matrix completeness across data sets. Phylogenetic resolution was greatly improved across the tree, at both shallow and deep levels. Concatenation and coalescent-based approaches both resolve the sister lineage of the cacti with strong support: Anacampserotaceae $+$ Portulacaceae, two lineages of mostly diminutive succulent herbs of warm, arid regions. In spite of this congruence, BUCKy concordance analyses demonstrated strong and conflicting signals across gene trees. Our results add to the growing number of examples illustrating the complexity of phylogenetic signals in genomic-scale data.

  15. Evidence of Sympatry of Clade A and Clade B Head Lice in a Pre-Columbian Chilean Mummy from Camarones

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    Boutellis, Amina; Drali, Rezak; Rivera, Mario A.; Mumcuoglu, Kosta Y.; Raoult, Didier

    2013-01-01

    Three different lineages of head lice are known to parasitize humans. Clade A, which is currently worldwide in distribution, was previously demonstrated to be present in the Americas before the time of Columbus. The two other types of head lice are geographically restricted to America and Australia for clade B and to Africa and Asia for clade C. In this study, we tested two operculated nits from a 4,000-year-old Chilean mummy of Camarones for the presence of the partial Cytb mitochondrial gene (270 bp). Our finding shows that clade B head lice were present in America before the arrival of the European colonists. PMID:24204678

  16. Sequential and Simultaneous Immunization of Rabbits with HIV-1 Envelope Glycoprotein SOSIP.664 Trimers from Clades A, B and C

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    Klasse, P. J.; LaBranche, Celia C.; Ketas, Thomas J.; Ozorowski, Gabriel; Cupo, Albert; Pugach, Pavel; Ringe, Rajesh P.; Golabek, Michael; van Gils, Marit J.; Guttman, Miklos; Lee, Kelly K.; Wilson, Ian A.; Butera, Salvatore T.; Ward, Andrew B.; Montefiori, David C.; Sanders, Rogier W.; Moore, John P.

    2016-01-01

    We have investigated the immunogenicity in rabbits of native-like, soluble, recombinant SOSIP.664 trimers based on the env genes of four isolates of human immunodeficiency virus type 1 (HIV-1); specifically BG505 (clade A), B41 (clade B), CZA97 (clade C) and DU422 (clade C). The various trimers were

  17. Multi-gene phylogenetic analysis reveals that shochu-fermenting Saccharomyces cerevisiae strains form a distinct sub-clade of the Japanese sake cluster.

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    Futagami, Taiki; Kadooka, Chihiro; Ando, Yoshinori; Okutsu, Kayu; Yoshizaki, Yumiko; Setoguchi, Shinji; Takamine, Kazunori; Kawai, Mikihiko; Tamaki, Hisanori

    2017-10-01

    Shochu is a traditional Japanese distilled spirit. The formation of the distinguishing flavour of shochu produced in individual distilleries is attributed to putative indigenous yeast strains. In this study, we performed the first (to our knowledge) phylogenetic classification of shochu strains based on nucleotide gene sequences. We performed phylogenetic classification of 21 putative indigenous shochu yeast strains isolated from 11 distilleries. All of these strains were shown or confirmed to be Saccharomyces cerevisiae, sharing species identification with 34 known S. cerevisiae strains (including commonly used shochu, sake, ale, whisky, bakery, bioethanol and laboratory yeast strains and clinical isolate) that were tested in parallel. Our analysis used five genes that reflect genome-level phylogeny for the strain-level classification. In a first step, we demonstrated that partial regions of the ZAP1, THI7, PXL1, YRR1 and GLG1 genes were sufficient to reproduce previous sub-species classifications. In a second step, these five analysed regions from each of 25 strains (four commonly used shochu strains and the 21 putative indigenous shochu strains) were concatenated and used to generate a phylogenetic tree. Further analysis revealed that the putative indigenous shochu yeast strains form a monophyletic group that includes both the shochu yeasts and a subset of the sake group strains; this cluster is a sister group to other sake yeast strains, together comprising a sake-shochu group. Differences among shochu strains were small, suggesting that it may be possible to correlate subtle phenotypic differences among shochu flavours with specific differences in genome sequences. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  18. Up and down the blind alley: population divergence with scant gene flow in an endangered tropical lineage of Andean palms (Ceroxylon quindiuense clade: Ceroxyloideae).

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    Sanín, María José; Zapata, Patricia; Pintaud, Jean-Christophe; Galeano, Gloria; Bohórquez, Adriana; Tohme, Joseph; Hansen, Michael Møller

    2017-02-10

    Given the geographical complexity of the Andes, species distributions hold interesting information regarding the history of isolation and gene flow across geographic barriers and ecological gradients. Moreover, current threats to the region’s enormous plant diversity pose an additional challenge to the understanding of these patterns. We explored the geographic structure of genetic diversity within the Ceroxylon quindiuense species complex (wax palms) at a regional scale, using a model-based approach to disentangle the historical mechanisms by which these species have dispersed over a range encompassing 17° of latitude in the tropical Andes. A total of 10 microsatellite loci were cross-amplified in 8 populations of the 3 species comprising the C. quindiuense complex. Analyses performed include estimates of molecular diversity and genetic structure, testing for genetic bottlenecks and an evaluation of the colonization scenario under approximate Bayesian computation. We showed that there was a geographical diversity gradient reflecting the orogenetic pattern of the northern Andes and its end at the cordilleras facing the Caribbean Sea. A general pattern of diversity suggests that the cordilleras of Colombia have served as historical recipients of gene flow occurring only scantly along the northern Andes. We provided evidence of important isolation between the largest populations of this complex, suggesting that both historical constraints to dispersal but also current anthropogenic effects might explain the high levels of population structuring. We provide a list of advisable measures for conservation stakeholders.

  19. Cytogenetics of Legumes in the Phaseoloid Clade

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    Aiko Iwata

    2013-11-01

    Full Text Available Cytogenetics played an essential role in studies of chromosome structure, behavior, and evolution in numerous plant species. The advent of molecular cytogenetics combined with recent development of genomic resources has ushered in a new era of chromosome studies that have greatly advanced our knowledge of karyotypic diversity, genome and chromosome organization, and chromosomal evolution in legumes. This review summarizes some of the achievements of cytogenetic studies in legumes in the Phaseoloid clade, which includes several important legume crops such as common bean ( L., cowpea [ (L. Walp.], soybean [ (L. Merr.], and pigeonpea [ (L. Huth]. In the Phaseoloid clade, karyotypes are mostly stable. There are, however, several species with extensive chromosomal changes. Fluorescence in situ hybridization has been useful to reveal chromosomal structure by physically mapping transposons, satellite repeats, ribosomal DNA genes, and bacterial artificial chromosome clones onto chromosomes. Polytene chromosomes, which are much longer than the mitotic chromosomes, have been successfully found and used in cytogenetic studies in some and species. Molecular cytogenetics will continue to be an important tool in legume genetics and genomics, and we discuss future applications of molecular cytogenetics to better understand chromosome and genome structure and evolution in legumes.

  20. Vaccine protection of chickens against antigenically diverse H5 highly pathogenic avian influenza isolates with a live HVT vector vaccine expressing the influenza hemagglutinin gene derived from a clade 2.2 avian influenza virus.

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    Kapczynski, Darrell R; Esaki, Motoyuki; Dorsey, Kristi M; Jiang, Haijun; Jackwood, Mark; Moraes, Mauro; Gardin, Yannick

    2015-02-25

    Vaccination is an important tool in the protection of poultry against avian influenza (AI). For field use, the overwhelming majority of AI vaccines produced are inactivated whole virus formulated into an oil emulsion. However, recombinant vectored vaccines are gaining use for their ability to induce protection against heterologous isolates and ability to overcome maternal antibody interference. In these studies, we compared protection of chickens provided by a turkey herpesvirus (HVT) vector vaccine expressing the hemagglutinin (HA) gene from a clade 2.2 H5N1 strain (A/swan/Hungary/4999/2006) against homologous H5N1 as well as heterologous H5N1 and H5N2 highly pathogenic (HP) AI challenge. The results demonstrated all vaccinated birds were protected from clinical signs of disease and mortality following homologous challenge. In addition, oral and cloacal swabs taken from challenged birds demonstrated that vaccinated birds had lower incidence and titers of viral shedding compared to sham-vaccinated birds. Following heterologous H5N1 or H5N2 HPAI challenge, 80-95% of birds receiving the HVT vector AI vaccine at day of age survived challenge with fewer birds shedding virus after challenge than sham vaccinated birds. In vitro cytotoxicity analysis demonstrated that splenic T lymphocytes from HVT-vector-AI vaccinated chickens recognized MHC-matched target cells infected with H5, as well as H6, H7, or H9 AI virus. Taken together, these studies provide support for the use of HVT vector vaccines expressing HA to protect poultry against multiple lineages of HPAI, and that both humoral and cellular immunity induced by live vaccines likely contributes to protection. Published by Elsevier Ltd.

  1. Molecular characteristic and pathogenicity of Indonesian H5N1 clade 2.3.2 viruses

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    Dharmayanti NLPI

    2013-06-01

    Full Text Available The outbreak of disease in late 2012 in Indonesia caused high duck mortality. The agent of the disease was identified as H5N1 clade 2.3.2. The disease caused economic loss to the Indonesian duck farmer. The clade 2.3.2 of H5N1 virus has not previously been identified, so this study was conducted to characterize 4 of H5N1 clade 2.3.2 viruses by DNA sequencing in eight genes segment virus namely HA, NA, NS, M, PB1, PB2, PA and NP. The pathogenicity test of clade 2.3.2 viruses in ducks was compared to clade 2.1.3 viruses which predominat circulating in Indonesia. Results of phylogenetic tree analysis showed that the four of clade 2.3.2 viruses isolated in 2012 was the new introduced virus from abroad. Further analysis showed eight genes were in one group with the clade 2.3.2 viruses, especially those from VietNam and did not belong to Indonesia viruses group. The pathogenicity test in ducks showed that virus H5N1 clade 2.3.2 and clade 2.1.3 have similar clinical symptoms and pathogenicity and cause death in 75% of ducks on days 3-6 after infection.

  2. Major clades of Agaricales: a multilocus phylogenetic overview.

    Science.gov (United States)

    P. Brandon Matheny; Judd M. Curtis; Valerie Hofstetter; M. Catherine Aime; Jean-Marc Moncalvo; Zai-Wei Ge; Zhu-Liang Yang; Joseph F. Ammirati; Timothy J. Baroni; Neale L. Bougher; Karen W. Lodge Hughes; Richard W. Kerrigan; Michelle T. Seidl; Aanen; Matthew Duur K. DeNitis; Graciela M. Daniele; Dennis E. Desjardin; Bradley R. Kropp; Lorelei L. Norvell; Andrew Parker; Else C. Vellinga; Rytas Vilgalys; David S. Hibbett

    2006-01-01

    An overview of the phylogeny of the Agaricales is presented based on a multilocus analysis of a six-gene region supermatrix. Bayesian analyses of 5611 nucleotide characters of rpb1, rpb1-intron 2, rpb2 and 18S, 25S, and 5.8S ribosomal RNA genes recovered six major clades, which are recognized informally and labeled the Agaricoid, Tricholomatoid, Marasmioid, Pluteoid,...

  3. Expanding the World of Marine Bacterial and Archaeal Clades

    Science.gov (United States)

    Yilmaz, Pelin; Yarza, Pablo; Rapp, Josephine Z.; Glöckner, Frank O.

    2016-01-01

    Determining which microbial taxa are out there, where they live, and what they are doing is a driving approach in marine microbial ecology. The importance of these questions is underlined by concerted, large-scale, and global ocean sampling initiatives, for example the International Census of Marine Microbes, Ocean Sampling Day, or Tara Oceans. Given decades of effort, we know that the large majority of marine Bacteria and Archaea belong to about a dozen phyla. In addition to the classically culturable Bacteria and Archaea, at least 50 “clades,” at different taxonomic depths, exist. These account for the majority of marine microbial diversity, but there is still an underexplored and less abundant portion remaining. We refer to these hitherto unrecognized clades as unknown, as their boundaries, names, and classifications are not available. In this work, we were able to characterize up to 92 of these unknown clades found within the bacterial and archaeal phylogenetic diversity currently reported for marine water column environments. We mined the SILVA 16S rRNA gene datasets for sequences originating from the marine water column. Instead of the usual subjective taxa delineation and nomenclature methods, we applied the candidate taxonomic unit (CTU) circumscription system, along with a standardized nomenclature to the sequences in newly constructed phylogenetic trees. With this new phylogenetic and taxonomic framework, we performed an analysis of ICoMM rRNA gene amplicon datasets to gain insights into the global distribution of the new marine clades, their ecology, biogeography, and interaction with oceanographic variables. Most of the new clades we identified were interspersed by known taxa with cultivated members, whose genome sequences are available. This result encouraged us to perform metabolic predictions for the novel marine clades using the PICRUSt approach. Our work also provides an update on the taxonomy of several phyla and widely known marine clades as

  4. Separate introns gained within short and long soluble peridinin-chlorophyll a-protein genes during radiation of Symbiodinium (Dinophyceae) clade A and B lineages - PLoS One

    Science.gov (United States)

    Here we document introns in two Symbiodinium clades that were most likely gained following divergence of this genus from other peridinin-containing dinoflagellate lineages. Soluble peridinin-chlorophyll a-proteins (sPCP) occur in short and long forms in different species, and all...

  5. Overexpressed Proteins in Hypervirulent Clade 8 and Clade 6 Strains of Escherichia coli O157:H7 Compared to E. coli O157:H7 EDL933 Clade 3 Strain.

    Directory of Open Access Journals (Sweden)

    Natalia Amigo

    Full Text Available Escherichia coli O157:H7 is responsible for severe diarrhea and hemolytic uremic syndrome (HUS, and predominantly affects children under 5 years. The major virulence traits are Shiga toxins, necessary to develop HUS and the Type III Secretion System (T3SS through which bacteria translocate effector proteins directly into the host cell. By SNPs typing, E. coli O157:H7 was separated into nine different clades. Clade 8 and clade 6 strains were more frequently associated with severe disease and HUS. In this study, we aimed to identify differentially expressed proteins in two strains of E. coli O157:H7 (clade 8 and clade 6, obtained from cattle and compared them with the well characterized reference EDL933 strain (clade 3. Clade 8 and clade 6 strains show enhanced pathogenicity in a mouse model and virulence-related properties. Proteins were extracted and analyzed using the TMT-6plex labeling strategy associated with two dimensional liquid chromatography and mass spectrometry in tandem. We detected 2241 proteins in the cell extract and 1787 proteins in the culture supernatants. Attention was focused on the proteins related to virulence, overexpressed in clade 6 and 8 strains compared to EDL933 strain. The proteins relevant overexpressed in clade 8 strain were the curli protein CsgC, a transcriptional activator (PchE, phage proteins, Stx2, FlgM and FlgD, a dienelactone hydrolase, CheW and CheY, and the SPATE protease EspP. For clade 6 strain, a high overexpression of phage proteins was detected, mostly from Stx2 encoding phage, including Stx2, flagellin and the protease TagA, EDL933_p0016, dienelactone hydrolase, and Haemolysin A, amongst others with unknown function. Some of these proteins were analyzed by RT-qPCR to corroborate the proteomic data. Clade 6 and clade 8 strains showed enhanced transcription of 10 out of 12 genes compared to EDL933. These results may provide new insights in E. coli O157:H7 mechanisms of pathogenesis.

  6. Genetic tools for the investigation of Roseobacter clade bacteria

    Directory of Open Access Journals (Sweden)

    Tielen Petra

    2009-12-01

    Full Text Available Abstract Background The Roseobacter clade represents one of the most abundant, metabolically versatile and ecologically important bacterial groups found in marine habitats. A detailed molecular investigation of the regulatory and metabolic networks of these organisms is currently limited for many strains by missing suitable genetic tools. Results Conjugation and electroporation methods for the efficient and stable genetic transformation of selected Roseobacter clade bacteria including Dinoroseobacter shibae, Oceanibulbus indolifex, Phaeobacter gallaeciensis, Phaeobacter inhibens, Roseobacter denitrificans and Roseobacter litoralis were tested. For this purpose an antibiotic resistance screening was performed and suitable genetic markers were selected. Based on these transformation protocols stably maintained plasmids were identified. A plasmid encoded oxygen-independent fluorescent system was established using the flavin mononucleotide-based fluorescent protein FbFP. Finally, a chromosomal gene knockout strategy was successfully employed for the inactivation of the anaerobic metabolism regulatory gene dnr from D. shibae DFL12T. Conclusion A genetic toolbox for members of the Roseobacter clade was established. This provides a solid methodical basis for the detailed elucidation of gene regulatory and metabolic networks underlying the ecological success of this group of marine bacteria.

  7. Rapid Differentiation between Livestock-Associated and Livestock-Independent Staphylococcus aureus CC398 Clades

    Science.gov (United States)

    Larsen, Jesper; Soldanova, Katerina; Aziz, Maliha; Contente-Cuomo, Tania; Petersen, Andreas; Vandendriessche, Stien; Jiménez, Judy N.; Mammina, Caterina; van Belkum, Alex; Salmenlinna, Saara; Laurent, Frederic; Skov, Robert L.; Larsen, Anders R.; Andersen, Paal S.; Price, Lance B.

    2013-01-01

    Staphylococcus aureus clonal complex 398 (CC398) isolates cluster into two distinct phylogenetic clades based on single-nucleotide polymorphisms (SNPs) revealing a basal human clade and a more derived livestock clade. The scn and tet(M) genes are strongly associated with the human and the livestock clade, respectively, due to loss and acquisition of mobile genetic elements. We present canonical single-nucleotide polymorphism (canSNP) assays that differentiate the two major host-associated S. aureus CC398 clades and a duplex PCR assay for detection of scn and tet(M). The canSNP assays correctly placed 88 S. aureus CC398 isolates from a reference collection into the human and livestock clades and the duplex PCR assay correctly identified scn and tet(M). The assays were successfully applied to a geographically diverse collection of 272 human S. aureus CC398 isolates. The simple assays described here generate signals comparable to a whole-genome phylogeny for major clade assignment and are easily integrated into S. aureus CC398 surveillance programs and epidemiological studies. PMID:24244535

  8. Anuran trypanosomes: phylogenetic evidence for new clades in Brazil.

    Science.gov (United States)

    da S Ferreira, Juliana I G; da Costa, Andrea P; Ramirez, Diego; Roldan, Jairo A M; Saraiva, Danilo; da S Founier, Gislene F R; Sue, Ana; Zambelli, Erick R; Minervino, Antonio H H; Verdade, Vanessa K; Gennari, Solange M; Marcili, Arlei

    2015-05-01

    Trypanosomes of anurans and fish are grouped into the Aquatic Clade which includes species isolated from fish, amphibians, turtles and platypus, usually transmitted by leeches and phlebotomine sand flies. Trypanosomes from Brazilian frogs are grouped within the Aquatic Clade with other anuran trypanosome species, where there seems to be coevolutionary patterns with vertebrate hosts and association to Brazilian biomes (Atlantic Forest, Pantanal and Amazonia Rainforest). We characterised the anuran trypanosomes from two different areas of the Cerrado biome and examined their phylogenetic relationships based on the SSU rRNA gene. A total of 112 anurans of six species was analysed and trypanosome prevalence evaluated through haemoculture was found to be 7% (8 positive frogs). However, only three isolates (2.7%) from two anuran species were recovered and cryopreserved. Analysis including SSU rDNA sequences from previous studies segregated the anuran trypanosomes into six groups, the previously reported An01 to An04, and An05 and An06 reported herein. Clade An05 comprises the isolates from Leptodactylus latrans (Steffen) and Pristimantis sp. captured in the Cerrado biome and Trypanosoma chattoni Mathis & Leger, 1911. The inclusion of new isolates in the phylogenetic analyses provided evidence for a new group (An06) of parasites from phlebotomine hosts. Our results indicate that the diversity of trypanosome species is underestimated since studies conducted in Brazil and other regions of the world are still few.

  9. Taxonomic evaluation of species in the Streptomyces hirsutus clade using multi-locus sequence analysis and proposals to reclassify several species in this clade

    Science.gov (United States)

    Previous phylogenetic analyses of species of Streptomyces based on 16S rRNA gene sequences resulted in a statistically well-supported clade (100% bootstrap value) containing 8 species that exhibited very similar gross morphology in producing open looped (Retinaculum-Apertum) to spiral (Spira) chains...

  10. Clade identification of symbiotic zooxanthellae of dominant ...

    African Journals Online (AJOL)

    Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium were amplified by polymerase chain reaction (PCR) and then PCR products were analyzed by the phylogenetic analyses of the LSU DNA sequences based on PAUP and Clustal X software. The results showed that there are at least two clades of Symbiodinium from ...

  11. Influenza A H5N1 clade 2.3.4 virus with a different antiviral susceptibility profile replaced clade 1 virus in humans in northern Vietnam.

    Directory of Open Access Journals (Sweden)

    Mai T Q Le

    2008-10-01

    Full Text Available Prior to 2007, highly pathogenic avian influenza (HPAI H5N1 viruses isolated from poultry and humans in Vietnam were consistently reported to be clade 1 viruses, susceptible to oseltamivir but resistant to amantadine. Here we describe the re-emergence of human HPAI H5N1 virus infections in Vietnam in 2007 and the characteristics of the isolated viruses.Respiratory specimens from patients suspected to be infected with avian influenza in 2007 were screened by influenza and H5 subtype specific polymerase chain reaction. Isolated H5N1 strains were further characterized by genome sequencing and drug susceptibility testing. Eleven poultry outbreak isolates from 2007 were included in the sequence analysis. Eight patients, all of them from northern Vietnam, were diagnosed with H5N1 in 2007 and five of them died. Phylogenetic analysis of H5N1 viruses isolated from humans and poultry in 2007 showed that clade 2.3.4 H5N1 viruses replaced clade 1 viruses in northern Vietnam. Four human H5N1 strains had eight-fold reduced in-vitro susceptibility to oseltamivir as compared to clade 1 viruses. In two poultry isolates the I117V mutation was found in the neuraminidase gene, which is associated with reduced susceptibility to oseltamivir. No mutations in the M2 gene conferring amantadine resistance were found.In 2007, H5N1 clade 2.3.4 viruses replaced clade 1 viruses in northern Vietnam and were susceptible to amantadine but showed reduced susceptibility to oseltamivir. Combination antiviral therapy with oseltamivir and amantadine for human cases in Vietnam is recommended.

  12. Biotechnological Applications of the Roseobacter Clade

    DEFF Research Database (Denmark)

    Bentzon-Tilia, Mikkel; Gram, Lone

    2017-01-01

    spectrum of Gram-positive and Gram-negative bacteria in which resistance towards the compound does not arise easily. Mining the genomes of roseobacters also reveal that they are likely capable of producing other compounds than hitherto discovered by classical bio-assay guided fractionation, since...... the genomes contain genes/gene clusters probably encoding unknown bioactive secondary metabolites. Therefore, bacteria of the Roseobacter clade may serve as potential sources of novel bioactive compounds, including novel antibiotics, which is of paramount importance in the battle against antibiotic resistant...... pathogenic bacteria. The discovery of new antibiotic compounds is not the only means by which we can counter the spread of antibiotic resistance. Development of sustainable alternatives to the application of antibiotics in agri- and aquaculture may be equally important. Attributable to their inherent...

  13. Genomic differentiation among two strains of the PS1 clade isolated from geographically separated marine habitats

    KAUST Repository

    Jimenez Infante, Francy M.

    2014-05-22

    Using dilution-to-extinction cultivation, we isolated a strain affiliated with the PS1 clade from surface waters of the Red Sea. Strain RS24 represents the second isolate of this group of marine Alphaproteobacteria after IMCC14465 that was isolated from the East (Japan) Sea. The PS1 clade is a sister group to the OCS116 clade, together forming a putatively novel order closely related to Rhizobiales. While most genomic features and most of the genetic content are conserved between RS24 and IMCC14465, their average nucleotide identity (ANI) is < 81%, suggesting two distinct species of the PS1 clade. Next to encoding two different variants of proteorhodopsin genes, they also harbor several unique genomic islands that contain genes related to degradation of aromatic compounds in IMCC14465 and in polymer degradation in RS24, possibly reflecting the physicochemical differences in the environment they were isolated from. No clear differences in abundance of the genomic content of either strain could be found in fragment recruitment analyses using different metagenomic datasets, in which both genomes were detectable albeit as minor part of the communities. The comparative genomic analysis of both isolates of the PS1 clade and the fragment recruitment analysis provide first insights into the ecology of this group. © 2014 Federation of European Microbiological Societies.

  14. Phylogenetic analysis of New Zealand earthworms (Oligochaeta: Megascolecidae) reveals ancient clades and cryptic taxonomic diversity.

    Science.gov (United States)

    Buckley, Thomas R; James, Sam; Allwood, Julia; Bartlam, Scott; Howitt, Robyn; Prada, Diana

    2011-01-01

    We have constructed the first ever phylogeny for the New Zealand earthworm fauna (Megascolecinae and Acanthodrilinae) including representatives from other major continental regions. Bayesian and maximum likelihood phylogenetic trees were constructed from 427 base pairs from the mitochondrial large subunit (16S) rRNA gene and 661 base pairs from the nuclear large subunit (28S) rRNA gene. Within the Acanthodrilinae we were able to identify a number of well-supported clades that were restricted to continental landmasses. Estimates of nodal support for these major clades were generally high, but relationships among clades were poorly resolved. The phylogenetic analyses revealed several independent lineages in New Zealand, some of which had a comparable phylogenetic depth to monophyletic groups sampled from Madagascar, Africa, North America and Australia. These results are consistent with at least some of these clades having inhabited New Zealand since rifting from Gondwana in the Late Cretaceous. Within the New Zealand Acanthodrilinae, major clades tended to be restricted to specific regions of New Zealand, with the central North Island and Cook Strait representing major biogeographic boundaries. Our field surveys of New Zealand and subsequent identification has also revealed extensive cryptic taxonomic diversity with approximately 48 new species sampled in addition to the 199 species recognized by previous authors. Our results indicate that further survey and taxonomic work is required to establish a foundation for future biogeographic and ecological research on this vitally important component of the New Zealand biota. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. Herbivory increases diversification across insect clades.

    Science.gov (United States)

    Wiens, John J; Lapoint, Richard T; Whiteman, Noah K

    2015-09-24

    Insects contain more than half of all living species, but the causes of their remarkable diversity remain poorly understood. Many authors have suggested that herbivory has accelerated diversification in many insect clades. However, others have questioned the role of herbivory in insect diversification. Here, we test the relationships between herbivory and insect diversification across multiple scales. We find a strong, positive relationship between herbivory and diversification among insect orders. However, herbivory explains less variation in diversification within some orders (Diptera, Hemiptera) or shows no significant relationship with diversification in others (Coleoptera, Hymenoptera, Orthoptera). Thus, we support the overall importance of herbivory for insect diversification, but also show that its impacts can vary across scales and clades. In summary, our results illuminate the causes of species richness patterns in a group containing most living species, and show the importance of ecological impacts on diversification in explaining the diversity of life.

  16. Molecular relationships of fungi within the Fusarium redolens - F. hostae clade

    NARCIS (Netherlands)

    Baayen, R.P.; O'Donnell, K.; Breeuwsma, S.; Geiser, D.M.; Waalwijk, C.

    2001-01-01

    The evolutionary relationships of fungi in the Fusarium redolens - F. hostae clade were investigated by constructing nuclear and mitochondrial gene genealogies for 37 isolates representing the known genetic and pathogenic diversity of this lineage, together with 15 isolates from putative sister

  17. Amphitremida (poche, 1913 is a new major, ubiquitous labyrinthulomycete clade.

    Directory of Open Access Journals (Sweden)

    Fatma Gomaa

    Full Text Available Micro-eukaryotic diversity is poorly documented at all taxonomic levels and the phylogenetic affiliation of many taxa - including many well-known and common organisms - remains unknown. Among these incertae sedis taxa are Archerella flavum (Loeblich and Tappan, 1961 and Amphitrema wrightianum (Archer, 1869 (Amphitremidae, two filose testate amoebae commonly found in Sphagnum peatlands. To clarify their phylogenetic position, we amplified and sequenced the SSU rRNA gene obtained from four independent DNA extractions of A. flavum and three independent DNA extractions of A. wrightianum. Our molecular data demonstrate that genera Archerella and Amphitrema form a fully supported deep-branching clade within the Labyrinthulomycetes (Stramenopiles, together with Diplophrys sp. (ATCC50360 and several environmental clones obtained from a wide range of environments. This newly described clade we named Amphitremida is diverse genetically, ecologically and physiologically. Our phylogenetic analysis suggests that osmotrophic species evolved most likely from phagotrophic ancestors and that the bothrosome, an organelle that produces cytoplasmic networks used for attachment to the substratum and to absorb nutrients from the environments, appeared lately in labyrithulomycete evolution.

  18. Distinct Processes Drive Diversification in Different Clades of Gesneriaceae.

    Science.gov (United States)

    Roalson, Eric H; Roberts, Wade R

    2016-07-01

    Using a time-calibrated phylogenetic hypothesis including 768 Gesneriaceae species (out of [Formula: see text]3300 species) and more than 29,000 aligned bases from 26 gene regions, we test Gesneriaceae for diversification rate shifts and the possible proximal drivers of these shifts: geographic distributions, growth forms, and pollination syndromes. Bayesian Analysis of Macroevolutionary Mixtures analyses found five significant rate shifts in Beslerieae, core Nematanthus, core Columneinae, core Streptocarpus, and Pacific Cyrtandra These rate shifts correspond with shifts in diversification rates, as inferred by Binary State Speciation and Extinction Model and Geographic State Speciation and Extinction model, associated with hummingbird pollination, epiphytism, unifoliate growth, and geographic area. Our results suggest that diversification processes are extremely variable across Gesneriaceae clades with different combinations of characters influencing diversification rates in different clades. Diversification patterns between New and Old World lineages show dramatic differences, suggesting that the processes of diversification in Gesneriaceae are very different in these two geographic regions. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Phylogeny of the sea hares in the aplysia clade based on mitochondrial DNA sequence data

    Energy Technology Data Exchange (ETDEWEB)

    Medina, Monica; Collins, Timothy; Walsh, Patrick J.

    2004-02-20

    Sea hare species within the Aplysia clade are distributed worldwide. Their phylogenetic and biogeographic relationships are, however, still poorly known. New molecular evidence is presented from a portion of the mitochondrial cytochrome oxidase c subunit 1 gene (cox1) that improves our understanding of the phylogeny of the group. Based on these data a preliminary discussion of the present distribution of sea hares in a biogeographic context is put forward. Our findings are consistent with only some aspects of the current taxonomy and nomenclatural changes are proposed. The first, is the use of a rank free classification for the different Aplysia clades and subclades as opposed to previously used genus and subgenus affiliations. The second, is the suggestion that Aplysia brasiliana (Rang, 1828) is a junior synonym of Aplysia fasciata (Poiret, 1789). The third, is the elimination of Neaplysia since its only member is confirmed to be part of the large Varria clade.

  20. A revision of the Solanum elaeagnifolium clade (Elaeagnifolium clade; subgenus Leptostemonum, Solanaceae

    Directory of Open Access Journals (Sweden)

    Sandra Knapp

    2017-08-01

    Full Text Available The Solanum elaeagnifolium clade (Elaeagnifolium clade contains five species of small, often rhizomatous, shrubs from deserts and dry forests in North and South America. Members of the clade were previously classified in sections Leprophora, Nycterium and Lathyrocarpum, and were not thought to be closely related. The group is sister to the species-rich monophyletic Old World clade of spiny solanums. The species of the group have an amphitropical distribution, with three species in Mexico and the southwestern United States and three species in Argentina. Solanum elaeagnifolium occurs in both North and South America, and is a noxious invasive weed in dry areas worldwide. Members of the group are highly variable morphologically, and this variability has led to much synonymy, particularly in the widespread S. elaeagnifolium. We here review the taxonomic history, morphology, relationships and ecology of these species and provide keys for their identification, descriptions, full synonymy (including designations of lectotypes and nomenclatural notes. Illustrations, distribution maps and preliminary conservation assessments are provided for all species.

  1. Plasmodium falciparum dolichol phosphate mannose synthase represents a novel clade

    International Nuclear Information System (INIS)

    Shams-Eldin, Hosam; Santos de Macedo, Cristiana; Niehus, Sebastian; Dorn, Caroline; Kimmel, Juergen; Azzouz, Nahid; Schwarz, Ralph T.

    2008-01-01

    Dolichol phosphate mannose synthase (DPM) catalyzes the reaction between dolichol phosphate (Dol-P) and guanosine diphosphate mannose (GDP-Man) to form dolichol-phosphate-mannose (Dol-P-Man). This molecule acts as mannose donor for N-glycosylation and glycosylphosphatidylinositol (GPI) biosynthesis. The Plasmodium falciparum DPM1 (Pfdpm1) possesses a single predicted transmembrane region near the N-, but not the C-terminus. Here we show that the cloned Pfdpm1 gene failed to complement a Saccharomyces cerevisiae mutant indicating that the parasite gene does not belong to the baker's yeast group, as was previously assumed. Furthermore, Pfdpm1 was unable to complement a mouse mutant deficient in DPM but efficiently complements the Schizosaccharomyces pombe fission yeast mutant, indicating a difference between fission yeast and mammalian DPM genes. Therefore, we reanalyzed the hydrophobicity scales of all known DPMs and consequently reclassify the DPM clade into six major novel subgroups. Furthermore, we show that Pfdpm1 represents a unique enzyme among these subgroups

  2. increased specialisation causes the demise of animal clades

    OpenAIRE

    Raia, P.; Carotenuto, F.; Mondanaro, A.; Castiglione, S.; Passaro, F.; Saggese, F.; Melchionna, M.; Serio, C.; Alessio, L.; Silvestro, D.; Fortelius, M.

    2016-01-01

    Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs wi...

  3. Autecology of crenarchaeotal and bacterial clades in marine sediments and microbial mats

    OpenAIRE

    Kubo, Kyoko

    2011-01-01

    The focus of this thesis was the autecology of the Miscellaneous Crenarchaeotal Group (MCG), a phylum-level clade of Archaea occurring mostly in marine sediments. Sequences of MCG 16S rRNA genes have been retrieved from a wide range of marine and terrestrial habitats, such as deep subsurface sediments, hydrothermal sediments, mud volcanoes, estuaries, hot springs and freshwater lake sediments. MCG members seem to have no general preferences for a particular temperature or salinity. So far, no...

  4. The Longibrachiatum Clade of Trichoderma: a revision with new species

    Science.gov (United States)

    The Longibrachiatum Clade of Trichoderma is revised. Eight new species are described (T. aethiopicum, T. capillare, T. flagellatum, T. gillesii, T. gracile, T. pinnatum, T. saturnisporopsis, T. solani). The twenty-one species known to belong to the Longibrachiatum Clade are included in a synoptic ke...

  5. Subsurface clade of Geobacteraceae that predominates in a diversity of Fe(III)-reducing subsurface environments

    Science.gov (United States)

    Holmes, Dawn E.; O'Neil, Regina A.; Vrionis, Helen A.; N'Guessan, Lucie A.; Ortiz-Bernad, Irene; Larrahondo, Maria J.; Adams, Lorrie A.; Ward, Joy A.; Nicoll , Julie S.; Nevin, Kelly P.; Chavan, Milind A.; Johnson, Jessica P.; Long, Philip E.; Lovely, Derek R.

    2007-01-01

    There are distinct differences in the physiology of Geobacter species available in pure culture. Therefore, to understand the ecology of Geobacter species in subsurface environments, it is important to know which species predominate. Clone libraries were assembled with 16S rRNA genes and transcripts amplified from three subsurface environments in which Geobacter species are known to be important members of the microbial community: (1) a uranium-contaminated aquifer located in Rifle, CO, USA undergoing in situ bioremediation; (2) an acetate-impacted aquifer that serves as an analog for the long-term acetate amendments proposed for in situ uranium bioremediation and (3) a petroleum-contaminated aquifer in which Geobacter species play a role in the oxidation of aromatic hydrocarbons coupled with the reduction of Fe(III). The majority of Geobacteraceae 16S rRNA sequences found in these environments clustered in a phylogenetically coherent subsurface clade, which also contains a number of Geobacter species isolated from subsurface environments. Concatamers constructed with 43 Geobacter genes amplified from these sites also clustered within this subsurface clade. 16S rRNA transcript and gene sequences in the sediments and groundwater at the Rifle site were highly similar, suggesting that sampling groundwater via monitoring wells can recover the most active Geobacter species. These results suggest that further study of Geobacter species in the subsurface clade is necessary to accurately model the behavior of Geobacter species during subsurface bioremediation of metal and organic contaminants.

  6. Detection and Characterization of Clade 1 Reassortant H5N1 Viruses Isolated from Human Cases in Vietnam during 2013.

    Directory of Open Access Journals (Sweden)

    Sharmi W Thor

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 is endemic in Vietnamese poultry and has caused sporadic human infection in Vietnam since 2003. Human infections with HPAI H5N1 are of concern due to a high mortality rate and the potential for the emergence of pandemic viruses with sustained human-to-human transmission. Viruses isolated from humans in southern Vietnam have been classified as clade 1 with a single genome constellation (VN3 since their earliest detection in 2003. This is consistent with detection of this clade/genotype in poultry viruses endemic to the Mekong River Delta and surrounding regions. Comparison of H5N1 viruses detected in humans from southern Vietnamese provinces during 2012 and 2013 revealed the emergence of a 2013 reassortant virus with clade 1.1.2 hemagglutinin (HA and neuraminidase (NA surface protein genes but internal genes derived from clade 2.3.2.1a viruses (A/Hubei/1/2010-like; VN12. Closer analysis revealed mutations in multiple genes of this novel genotype (referred to as VN49 previously associated with increased virulence in animal models and other markers of adaptation to mammalian hosts. Despite the changes identified between the 2012 and 2013 genotypes analyzed, their virulence in a ferret model was similar. Antigenically, the 2013 viruses were less cross-reactive with ferret antiserum produced to the clade 1 progenitor virus, A/Vietnam/1203/2004, but reacted with antiserum produced against a new clade 1.1.2 WHO candidate vaccine virus (A/Cambodia/W0526301/2012 with comparable hemagglutination inhibition titers as the homologous antigen. Together, these results indicate changes to both surface and internal protein genes of H5N1 viruses circulating in southern Vietnam compared to 2012 and earlier viruses.

  7. Signature proteins for the major clades of Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Mathews Divya W

    2010-01-01

    Full Text Available Abstract Background The phylogeny and taxonomy of cyanobacteria is currently poorly understood due to paucity of reliable markers for identification and circumscription of its major clades. Results A combination of phylogenomic and protein signature based approaches was used to characterize the major clades of cyanobacteria. Phylogenetic trees were constructed for 44 cyanobacteria based on 44 conserved proteins. In parallel, Blastp searches were carried out on each ORF in the genomes of Synechococcus WH8102, Synechocystis PCC6803, Nostoc PCC7120, Synechococcus JA-3-3Ab, Prochlorococcus MIT9215 and Prochlor. marinus subsp. marinus CCMP1375 to identify proteins that are specific for various main clades of cyanobacteria. These studies have identified 39 proteins that are specific for all (or most cyanobacteria and large numbers of proteins for other cyanobacterial clades. The identified signature proteins include: (i 14 proteins for a deep branching clade (Clade A of Gloebacter violaceus and two diazotrophic Synechococcus strains (JA-3-3Ab and JA2-3-B'a; (ii 5 proteins that are present in all other cyanobacteria except those from Clade A; (iii 60 proteins that are specific for a clade (Clade C consisting of various marine unicellular cyanobacteria (viz. Synechococcus and Prochlorococcus; (iv 14 and 19 signature proteins that are specific for the Clade C Synechococcus and Prochlorococcus strains, respectively; (v 67 proteins that are specific for the Low B/A ecotype Prochlorococcus strains, containing lower ratio of chl b/a2 and adapted to growth at high light intensities; (vi 65 and 8 proteins that are specific for the Nostocales and Chroococcales orders, respectively; and (vii 22 and 9 proteins that are uniquely shared by various Nostocales and Oscillatoriales orders, or by these two orders and the Chroococcales, respectively. We also describe 3 conserved indels in flavoprotein, heme oxygenase and protochlorophyllide oxidoreductase proteins that

  8. Two novel species representing a new clade and cluster of Phytophthora.

    Science.gov (United States)

    Yang, Xiao; Copes, Warren E; Hong, Chuanxue

    2014-01-01

    Phytophthora stricta sp. nov. and Phytophthora macilentosa sp. nov. are described based on morphological, physiological and molecular characters in this study. Phytophthora stricta represents a previously unknown clade in the rRNA internal transcribed spacer (ITS)-based phylogeny. Phytophthora macilentosa, along with nine other species, consistently forms a high temperature-tolerant cluster within ITS clade 9. These observations are supported by the sequence analysis of the mitochondrial cytochrome c oxidase 1 gene. Both species are heterothallic and all examined isolates are A1 mating type. Phytophthora stricta produces nonpapillate and slightly caducous sporangia. This species is named after its characteristic constrictions on sporangiophores. Phytophthora macilentosa produces nonpapillate and noncaducous sporangia, which are mostly elongated obpyriform with a high length to breadth ratio. Both species were recovered from irrigation water of an ornamental plant nursery in Mississippi, USA and P. stricta was also recovered from stream water in Virginia, USA. Copyright © 2013 The British Mycological Society. All rights reserved.

  9. Characterization of Prochlorococcus clades from iron-depleted oceanic regions.

    Science.gov (United States)

    Rusch, Douglas B; Martiny, Adam C; Dupont, Christopher L; Halpern, Aaron L; Venter, J Craig

    2010-09-14

    Prochlorococcus describes a diverse and abundant genus of marine photosynthetic microbes. It is primarily found in oligotrophic waters across the globe and plays a crucial role in energy and nutrient cycling in the ocean ecosystem. The abundance, global distribution, and availability of isolates make Prochlorococcus a model system for understanding marine microbial diversity and biogeochemical cycling. Analysis of 73 metagenomic samples from the Global Ocean Sampling expedition acquired in the Atlantic, Pacific, and Indian Oceans revealed the presence of two uncharacterized Prochlorococcus clades. A phylogenetic analysis using six different genetic markers places the clades close to known lineages adapted to high-light environments. The two uncharacterized clades consistently cooccur and dominate the surface waters of high-temperature, macronutrient-replete, and low-iron regions of the Eastern Equatorial Pacific upwelling and the tropical Indian Ocean. They are genetically distinct from each other and other high-light Prochlorococcus isolates and likely define a previously unrecognized ecotype. Our detailed genomic analysis indicates that these clades comprise organisms that are adapted to iron-depleted environments by reducing their iron quota through the loss of several iron-containing proteins that likely function as electron sinks in the photosynthetic pathway in other Prochlorococcus clades from high-light environments. The presence and inferred physiology of these clades may explain why Prochlorococcus populations from iron-depleted regions do not respond to iron fertilization experiments and further expand our understanding of how phytoplankton adapt to variations in nutrient availability in the ocean.

  10. Why should we investigate the morphological disparity of plant clades?

    Science.gov (United States)

    Oyston, Jack W; Hughes, Martin; Gerber, Sylvain; Wills, Matthew A

    2016-04-01

    Disparity refers to the morphological variation in a sample of taxa, and is distinct from diversity or taxonomic richness. Diversity and disparity are fundamentally decoupled; many groups attain high levels of disparity early in their evolution, while diversity is still comparatively low. Diversity may subsequently increase even in the face of static or declining disparity by increasingly fine sub-division of morphological 'design' space (morphospace). Many animal clades reached high levels of disparity early in their evolution, but there have been few comparable studies of plant clades, despite their profound ecological and evolutionary importance. This study offers a prospective and some preliminary macroevolutionary analyses. Classical morphometric methods are most suitable when there is reasonable conservation of form, but lose traction where morphological differences become greater (e.g. in comparisons across higher taxa). Discrete character matrices offer one means to compare a greater diversity of forms. This study explores morphospaces derived from eight discrete data sets for major plant clades, and discusses their macroevolutionary implications. Most of the plant clades in this study show initial, high levels of disparity that approach or attain the maximum levels reached subsequently. These plant clades are characterized by an initial phase of evolution during which most regions of their empirical morphospaces are colonized. Angiosperms, palms, pines and ferns show remarkably little variation in disparity through time. Conifers furnish the most marked exception, appearing at relatively low disparity in the latest Carboniferous, before expanding incrementally with the radiation of successive, tightly clustered constituent sub-clades. Many cladistic data sets can be repurposed for investigating the morphological disparity of plant clades through time, and offer insights that are complementary to more focused morphometric studies. The unique structural and

  11. Evidence of a Native Northwest Atlantic COI Haplotype Clade in the Cryptogenic Colonial Ascidian Botryllus schlosseri.

    Science.gov (United States)

    Yund, Philip O; Collins, Catherine; Johnson, Sheri L

    2015-06-01

    The colonial ascidian Botryllus schlosseri should be considered cryptogenic (i.e., not definitively classified as either native or introduced) in the Northwest Atlantic. Although all the evidence is quite circumstantial, over the last 15 years most research groups have accepted the scenario of human-mediated dispersal and classified B. schlosseri as introduced; others have continued to consider it native or cryptogenic. We address the invasion status of this species by adding 174 sequences to the growing worldwide database for the mitochondrial gene cytochrome c oxidase subunit I (COI) and analyzing 1077 sequences to compare genetic diversity of one clade of haplotypes in the Northwest Atlantic with two hypothesized source regions (the Northeast Atlantic and Mediterranean). Our results lead us to reject the prevailing view of the directionality of transport across the Atlantic. We argue that the genetic diversity patterns at COI are far more consistent with the existence of at least one haplotype clade in the Northwest Atlantic (and possibly a second) that substantially pre-dates human colonization from Europe, with this native North American clade subsequently introduced to three sites in Northeast Atlantic and Mediterranean waters. However, we agree with past researchers that some sites in the Northwest Atlantic have more recently been invaded by alien haplotypes, so that some populations are currently composed of a mixture of native and invader haplotypes. © 2015 Marine Biological Laboratory.

  12. Molecular phylogeny and ecological diversification in a clade of New World songbirds (genus Vireo).

    Science.gov (United States)

    Cicero, C; Johnson, N K

    1998-10-01

    We constructed a molecular phylogeny for a clade of eye-ringed vireos (Vireo flavifrons and the V. solitarius complex) to examine existing hypotheses of speciation and ecological diversification. Complete sequences of the mtDNA cytochrome b gene were obtained from 47 individuals of this group plus four vireonid outgroups. Mean levels of sequence divergence in the clade varied from 0.29% to 5.7%. Differences were greatest between V. flavifrons and four taxa of 'V. solitarius'. The latter separated into three taxonomic, geographical and ecological groups: V. plumbeus plumbeus, V. cassinii cassinii, and V. solitarius solitarius plus V. solitarius alticola. These differed by an average of 2.6-3.2%. Populations within each group revealed low levels of sequence variation (x = 0.20%) and little geographical structuring. The mtDNA data generally corroborate results from allozymes. V. plumbeus shows a loss of yellow-green carotenoid pigmentation from the ancestral condition. The occupancy of relatively dry habitats by this species and V. cassinii represents a derived ecological shift from more-humid environments occupied by other species of vireonids. Ecological divergence in this clade occurred in allopatry and is associated with generic-level stability in morphometrics and foraging styles. Migratory behaviour and seasonal habitat shifts apparently evolved multiple times in vireos breeding in temperate environments. Present geographical and ecological distributions, and low levels of intrataxon genetic divergence, are hypothesized to be the result of postglacial regionalization of climate-plant associations and rapid northward expansion of breeding ranges.

  13. Bird evolution: testing the Metaves clade with six new mitochondrial genomes

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    Phillips Matthew J

    2008-01-01

    Full Text Available Abstract Background Evolutionary biologists are often misled by convergence of morphology and this has been common in the study of bird evolution. However, the use of molecular data sets have their own problems and phylogenies based on short DNA sequences have the potential to mislead us too. The relationships among clades and timing of the evolution of modern birds (Neoaves has not yet been well resolved. Evidence of convergence of morphology remain controversial. With six new bird mitochondrial genomes (hummingbird, swift, kagu, rail, flamingo and grebe we test the proposed Metaves/Coronaves division within Neoaves and the parallel radiations in this primary avian clade. Results Our mitochondrial trees did not return the Metaves clade that had been proposed based on one nuclear intron sequence. We suggest that the high number of indels within the seventh intron of the β-fibrinogen gene at this phylogenetic level, which left a dataset with not a single site across the alignment shared by all taxa, resulted in artifacts during analysis. With respect to the overall avian tree, we find the flamingo and grebe are sister taxa and basal to the shorebirds (Charadriiformes. Using a novel site-stripping technique for noise-reduction we found this relationship to be stable. The hummingbird/swift clade is outside the large and very diverse group of raptors, shore and sea birds. Unexpectedly the kagu is not closely related to the rail in our analysis, but because neither the kagu nor the rail have close affinity to any taxa within this dataset of 41 birds, their placement is not yet resolved. Conclusion Our phylogenetic hypothesis based on 41 avian mitochondrial genomes (13,229 bp rejects monophyly of seven Metaves species and we therefore conclude that the members of Metaves do not share a common evolutionary history within the Neoaves.

  14. Protein evolution in two co-occurring types of Symbiodinium: an exploration into the genetic basis of thermal tolerance in Symbiodinium clade D

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    Ladner Jason T

    2012-11-01

    Full Text Available Abstract Background The symbiosis between reef-building corals and photosynthetic dinoflagellates (Symbiodinium is an integral part of the coral reef ecosystem, as corals are dependent on Symbiodinium for the majority of their energy needs. However, this partnership is increasingly at risk due to changing climatic conditions. It is thought that functional diversity within Symbiodinium may allow some corals to rapidly adapt to different environments by changing the type of Symbiodinium with which they partner; however, very little is known about the molecular basis of the functional differences among symbiont groups. One group of Symbiodinium that is hypothesized to be important for the future of reefs is clade D, which, in general, seems to provide the coral holobiont (i.e., coral host and associated symbiont community with elevated thermal tolerance. Using high-throughput sequencing data from field-collected corals we assembled, de novo, draft transcriptomes for Symbiodinium clades C and D. We then explore the functional basis of thermal tolerance in clade D by comparing rates of coding sequence evolution among the four clades of Symbiodinium most commonly found in reef-building corals (A-D. Results We are able to highlight a number of genes and functional categories as candidates for involvement in the increased thermal tolerance of clade D. These include a fatty acid desaturase, molecular chaperones and proteins involved in photosynthesis and the thylakoid membrane. We also demonstrate that clades C and D co-occur within most of the sampled colonies of Acropora hyacinthus, suggesting widespread potential for this coral species to acclimatize to changing thermal conditions via ‘shuffling’ the proportions of these two clades from within their current symbiont communities. Conclusions Transcriptome-wide analysis confirms that the four main Symbiodinium clades found within corals exhibit extensive evolutionary divergence (18.5-27.3% avg

  15. Photosynthetic pigments of oceanic Chlorophyta belonging to prasinophytes clade VII.

    Science.gov (United States)

    Lopes Dos Santos, Adriana; Gourvil, Priscillia; Rodríguez, Francisco; Garrido, José Luis; Vaulot, Daniel

    2016-02-01

    The ecological importance and diversity of pico/nanoplanktonic algae remains poorly studied in marine waters, in part because many are tiny and without distinctive morphological features. Amongst green algae, Mamiellophyceae such as Micromonas or Bathycoccus are dominant in coastal waters while prasinophytes clade VII, yet not formerly described, appear to be major players in open oceanic waters. The pigment composition of 14 strains representative of different subclades of clade VII was analyzed using a method that improves the separation of loroxanthin and neoxanthin. All the prasinophytes clade VII analyzed here showed a pigment composition similar to that previously reported for RCC287 corresponding to pigment group prasino-2A. However, we detected in addition astaxanthin for which it is the first report in prasinophytes. Among the strains analyzed, the pigment signature is qualitatively similar within subclades A and B. By contrast, RCC3402 from subclade C (Picocystis) lacks loroxanthin, astaxanthin, and antheraxanthin but contains alloxanthin, diatoxanthin, and monadoxanthin that are usually found in diatoms or cryptophytes. For subclades A and B, loroxanthin was lowest at highest light irradiance suggesting a light-harvesting role of this pigment in clade VII as in Tetraselmis. © 2015 Phycological Society of America.

  16. Rapid Identification of Different Escherichia coli Sequence Type 131 Clades.

    Science.gov (United States)

    Matsumura, Yasufumi; Pitout, Johann D D; Peirano, Gisele; DeVinney, Rebekah; Noguchi, Taro; Yamamoto, Masaki; Gomi, Ryota; Matsuda, Tomonari; Nakano, Satoshi; Nagao, Miki; Tanaka, Michio; Ichiyama, Satoshi

    2017-08-01

    Escherichia coli sequence type 131 (ST131) is a pandemic clonal lineage that is responsible for the global increase in fluoroquinolone resistance and extended-spectrum-β-lactamase (ESBL) producers. The members of ST131 clade C, especially subclades C2 and C1-M27, are associated with ESBLs. We developed a multiplex conventional PCR assay with the ability to detect all ST131 clades (A, B, and C), as well as C subclades (C1-M27, C1-nM27 [C1-non-M27], and C2). To validate the assay, we used 80 ST131 global isolates that had been fully sequenced. We then used the assay to define the prevalence of each clade in two Japanese collections consisting of 460 ESBL-producing E. coli ST131 (2001-12) and 329 E. coli isolates from extraintestinal sites (ExPEC) (2014). The assay correctly identified the different clades in all 80 global isolates: clades A ( n = 12), B ( n = 12), and C, including subclades C1-M27 ( n = 16), C1-nM27 ( n = 20), C2 ( n = 17), and other C ( n = 3). The assay also detected all 565 ST131 isolates in both collections without any false positives. Isolates from clades A ( n = 54), B ( n = 23), and C ( n = 483) corresponded to the O serotypes and the fimH types of O16-H41, O25b-H22, and O25b-H30, respectively. Of the 483 clade C isolates, C1-M27 was the most common subclade (36%), followed by C1-nM27 (32%) and C2 (15%). The C1-M27 subclade with bla CTX-M-27 became especially prominent after 2009. Our novel multiplex PCR assay revealed the predominance of the C1-M27 subclade in recent Japanese ESBL-producing E. coli isolates and is a promising tool for epidemiological studies of ST131. Copyright © 2017 American Society for Microbiology.

  17. Into the Himalayan Exile: The Phylogeography of the Ground Beetle Ethira clade Supports the Tibetan Origin of Forest-Dwelling Himalayan Species Groups

    Science.gov (United States)

    Schmidt, Joachim; Opgenoorth, Lars; Höll, Steffen; Bastrop, Ralf

    2012-01-01

    The Himalayan mountain arc is one of the hotspots of biodiversity on earth, and species diversity is expected to be especially high among insects in this region. Little is known about the origin of the Himalayan insect fauna. With respect to the fauna of high altitude cloud forests, it has generally been accepted that Himalayan lineages are derived from ancestors that immigrated from Western Asia and from adjacent mountainous regions of East and Southeast Asia (immigration hypothesis). In this study, we sought to test a Tibetan Origin as an alternative hypothesis for groups with a poor dispersal ability through a phylogeographic analysis of the Ethira clade of the genus Pterostichus. We sequenced COI mtDNA and the 18S and 28S rDNA genes in 168 Pterostichini specimens, including 46 species and subspecies of the Ethira clade. In our analysis, we were able to show that the Ethira clade is monophyletic and, thus, represents a Himalayan endemic clade, supporting endemism of two of the basal lineages to the Central Himalaya and documenting large distributional gaps within the phylogeographic structure of the Ethira clade. Furthermore, the molecular data strongly indicate very limited dispersal abilities of species and subspecies of these primary wingless ground beetles. These results are consistent with the hypothesis of a Tibetan Origin, which explains the evolution, diversity and distribution of the Himalayan ground beetle Ethira clade much more parsimoniously than the original immigration hypothesis. PMID:23049805

  18. Phylogenomic analysis of the Chilean clade of Liolaemus lizards (Squamata: Liolaemidae based on sequence capture data

    Directory of Open Access Journals (Sweden)

    Alejandra Panzera

    2017-10-01

    Full Text Available The genus Liolaemus is one of the most ecologically diverse and species-rich genera of lizards worldwide. It currently includes more than 250 recognized species, which have been subject to many ecological and evolutionary studies. Nevertheless, Liolaemus lizards have a complex taxonomic history, mainly due to the incongruence between morphological and genetic data, incomplete taxon sampling, incomplete lineage sorting and hybridization. In addition, as many species have restricted and remote distributions, this has hampered their examination and inclusion in molecular systematic studies. The aims of this study are to infer a robust phylogeny for a subsample of lizards representing the Chilean clade (subgenus Liolaemus sensu stricto, and to test the monophyly of several of the major species groups. We use a phylogenomic approach, targeting 541 ultra-conserved elements (UCEs and 44 protein-coding genes for 16 taxa. We conduct a comparison of phylogenetic analyses using maximum-likelihood and several species tree inference methods. The UCEs provide stronger support for phylogenetic relationships compared to the protein-coding genes; however, the UCEs outnumber the protein-coding genes by 10-fold. On average, the protein-coding genes contain over twice the number of informative sites. Based on our phylogenomic analyses, all the groups sampled are polyphyletic. Liolaemus tenuis tenuis is difficult to place in the phylogeny, because only a few loci (nine were recovered for this species. Topologies or support values did not change dramatically upon exclusion of L. t. tenuis from analyses, suggesting that missing data did not had a significant impact on phylogenetic inference in this data set. The phylogenomic analyses provide strong support for sister group relationships between L. fuscus, L. monticola, L. nigroviridis and L. nitidus, and L. platei and L. velosoi. Despite our limited taxon sampling, we have provided a reliable starting hypothesis for

  19. Analysis of Ecological Distribution and Genomic Content from a Clade of Bacteroidetes Endemic to Sulfidic Environments

    Science.gov (United States)

    Zhou, K.; Sylvan, J. B.; Hallam, S. J.

    2017-12-01

    The Bacteroidetes are a ubiquitous phylum of bacteria found in a wide variety of habitats. Marine Bacteroidetes are known to utilize complex carbohydrates and have a potentially important role in the global carbon cycle through processing these compounds, which are not digestible by many other microbes. Some members of the phylum are known to perform denitrification and are facultative anaerobes, but Bacteroidetes are not known to participate in sulfur redox cycling. Recently, it was shown that a clade of uncultured Bacteroidetes, including the VC2.1_Bac22 group, appears to be endemic to sulfidic environments, including hydrothermal vent sulfide chimneys, sediments and marine water column oxygen minimum zones (OMZs). This clade, dubbed the Sulfiphilic Bacteroidetes, is not detected in 16S rRNA amplicon studies from non-sulfidic environments. To test the hypothesis that the Sulphiphilic Bacteroidetes are involved in sulfur redox chemistry, we updated our meta-analysis of the clade using 16s rRNA sequences from public databases and employed single-cell genomics to survey their genomic potential using 19 single amplified genomes (SAGs) isolated from the seasonally anoxic Saanich Inlet, a seasonally hypoxic basin in British Columbia. Initial analysis of these SAGs indicates the Sulphiphilic Bacteroidetes may perform sulfur redox reactions using a three gene psrABC operon encoding the polysulfide reductase enzyme complex with a thiosulfate sulfurtransferase (rhodanese), which putatively uses cyanide to convert thiosulfate to sulfite, just upstream. Interestingly, this is the same configuration as discovered recently in some Marine Group A bacteria. Further aspects of the Sulphiphilic Bacteroidetes' genomic potential will be presented in light of their presence in sulfidic environments.

  20. Detection and genomic characterization of motility in Lactobacillus curvatus: confirmation of motility in a species outside the Lactobacillus salivarius clade.

    Science.gov (United States)

    Cousin, Fabien J; Lynch, Shónagh M; Harris, Hugh M B; McCann, Angela; Lynch, Denise B; Neville, B Anne; Irisawa, Tomohiro; Okada, Sanae; Endo, Akihito; O'Toole, Paul W

    2015-02-01

    Lactobacillus is the largest genus within the lactic acid bacteria (LAB), with almost 180 species currently identified. Motility has been reported for at least 13 Lactobacillus species, all belonging to the Lactobacillus salivarius clade. Motility in lactobacilli is poorly characterized. It probably confers competitive advantages, such as superior nutrient acquisition and niche colonization, but it could also play an important role in innate immune system activation through flagellin–Toll-like receptor 5 (TLR5) interaction. We now report strong evidence of motility in a species outside the L. salivarius clade, Lactobacillus curvatus (strain NRIC0822). The motility of L. curvatus NRIC 0822 was revealed by phase-contrast microscopy and soft-agar motility assays. Strain NRIC 0822 was motile at temperatures between 15 °C and 37 °C, with a range of different carbohydrates, and under varying atmospheric conditions. We sequenced the L. curvatus NRIC 0822 genome, which revealed that the motility genes are organized in a single operon and that the products are very similar (>98.5% amino acid similarity over >11,000 amino acids) to those encoded by the motility operon of Lactobacillus acidipiscis KCTC 13900 (shown for the first time to be motile also). Moreover, the presence of a large number of mobile genetic elements within and flanking the motility operon of L. curvatus suggests recent horizontal transfer between members of two distinct Lactobacillus clades: L. acidipiscis in the L. salivarius clade and L. curvatus inthe L. sakei clade. This study provides novel phenotypic, genetic, and phylogenetic insights into flagellum-mediated motility in lactobacilli.

  1. Regressive Evolution of Photosynthesis in the Roseobacter Clade

    Czech Academy of Sciences Publication Activity Database

    Koblížek, Michal; Zeng, Yonghui; Horák, A.; Oborník, Miroslav

    2013-01-01

    Roč. 66, č. 2013 (2013), s. 385-405 ISSN 0065-2296 R&D Projects: GA ČR GAP501/10/0221; GA ČR GBP501/12/G055; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : roseobacter clade * photosynthesis * marine microbial communities Subject RIV: EE - Microbiology, Virology Impact factor: 1.740, year: 2013

  2. Virulence differences among Francisella tularensis subsp. tularensis clades in mice.

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    Claudia R Molins

    Full Text Available Francisella tularensis subspecies tularensis (type A and holarctica (type B are of clinical importance in causing tularemia. Molecular typing methods have further separated type A strains into three genetically distinct clades, A1a, A1b and A2. Epidemiological analyses of human infections in the United States suggest that A1b infections are associated with a significantly higher mortality rate as compared to infections caused by A1a, A2 and type B. To determine if genetic differences as defined by molecular typing directly correlate with differences in virulence, A1a, A1b, A2 and type B strains were compared in C57BL/6 mice. Here we demonstrate significant differences between survival curves for infections caused by A1b versus A1a, A2 and type B, with A1b infected mice dying earlier than mice infected with A1a, A2 or type B; these results were conserved among multiple strains. Differences were also detected among type A clades as well as between type A clades and type B with respect to bacterial burdens, and gross anatomy in infected mice. Our results indicate that clades defined within F. tularensis subsp. tularensis by molecular typing methods correlate with virulence differences, with A1b strains more virulent than A1a, A2 and type B strains. These findings indicate type A strains are not equivalent with respect to virulence and have important implications for public health as well as basic research programs.

  3. Seven wood-inhabiting new species of the genus Trichoderma (Fungi, Ascomycota) in Viride clade.

    Science.gov (United States)

    Qin, Wen-Tao; Zhuang, Wen-Ying

    2016-06-01

    More than 200 recent collections of Trichoderma from China were examined and 16 species belonging to the Viride clade were identified based on integrated studies of phenotypic and molecular data. Among them, seven wood-inhabiting new species, T. albofulvopsis, T. densum, T. laevisporum, T. sinokoningii, T. sparsum, T. sphaerosporum and T. subviride, are found. They form trichoderma- to verticillium-like conidiophores, lageniform to subulate phialides and globose to ellipsoidal conidia, but vary greatly in colony features, growth rates, and sizes of phialides and conidia. To explore their taxonomic positions, the phylogenetic tree including all the known species of the Viride clade is constructed based on sequence analyses of the combined RNA polymerase II subunit b and translation elongation factor 1 alpha exon genes. Our results indicated that the seven new species were well-located in the Koningii, Rogersonii and Neorufum subclades as well as a few independent terminal branches. They are clearly distinguishable from any existing species. Morphological distinctions and sequence divergences between the new species and their close relatives were discussed.

  4. Phylogenetic analysis of the lux operon distinguishes two evolutionarily distinct clades of Photobacterium leiognathi.

    Science.gov (United States)

    Ast, Jennifer C; Dunlap, Paul V

    2004-05-01

    The luminous marine bacterium Photobacterium mandapamensis was synonymized several years ago with Photobacterium leiognathi based on a high degree of phenotypic and genetic similarity. To test the possibility that P. leiognathi as now formulated, however, actually contains two distinct bacterial groups reflecting the earlier identification of P. mandapamensis and P. leiognathi as separate species, we compared P. leiognathi strains isolated from light-organ symbiosis with leiognathid fishes (i.e., ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1) with strains from seawater originally described as P. mandapamensis and later synonymized as P. leiognathi (i.e., ATCC 27561(T) and ATCC 33981) and certain strains initially identified as P. leiognathi (i.e., PL-721, PL-741, 554). Analysis of the 16S rRNA and gyrB genes did not resolve distinct clades, affirming a close relationship among these strains. However, strains ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554 were found to bear a luxF gene in the lux operon ( luxABFE), whereas ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1 lack this gene ( luxABE). Phylogenetic analysis of the luxAB(F)E region confirmed this distinction. Furthermore, ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554 all produced a higher level of luminescence on high-salt medium, as previously described for PL-721, whereas ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1 all produced a higher level of luminescence on low-salt medium, a characteristic of P. leiognathi from leiognathid fish light organs. These results demonstrate that P. leiognathi contains two evolutionarily and phenotypically distinct clades, P. leiognathi subsp. leiognathi (strains ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1), and P. leiognathi subsp. mandapamensis (strains ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554).

  5. Open source approaches to establishing Roseobacter clade bacteria as synthetic biology chassis for biogeoengineering

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    Yanika Borg

    2016-07-01

    Full Text Available Aim. The nascent field of bio-geoengineering stands to benefit from synthetic biologists’ efforts to standardise, and in so doing democratise, biomolecular research methods. Roseobacter clade bacteria comprise 15–20% of oceanic bacterio-plankton communities, making them a prime candidate for establishment of synthetic biology chassis for bio-geoengineering activities such as bioremediation of oceanic waste plastic. Developments such as the increasing affordability of DNA synthesis and laboratory automation continue to foster the establishment of a global ‘do-it-yourself’ research community alongside the more traditional arenas of academe and industry. As a collaborative group of citizen, student and professional scientists we sought to test the following hypotheses: (i that an incubator capable of cultivating bacterial cells can be constructed entirely from non-laboratory items, (ii that marine bacteria from the Roseobacter clade can be established as a genetically tractable synthetic biology chassis using plasmids conforming to the BioBrickTM standard and finally, (iii that identifying and subcloning genes from a Roseobacter clade species can readily by achieved by citizen scientists using open source cloning and bioinformatic tools. Method. We cultivated three Roseobacter species, Roseobacter denitrificans, Oceanobulbus indolifexand Dinoroseobacter shibae. For each species we measured chloramphenicol sensitivity, viability over 11 weeks of glycerol-based cryopreservation and tested the effectiveness of a series of electroporation and heat shock protocols for transformation using a variety of plasmid types. We also attempted construction of an incubator-shaker device using only publicly available components. Finally, a subgroup comprising citizen scientists designed and attempted a procedure for isolating the cold resistance anf1 gene from Oceanobulbus indolifexcells and subcloning it into a BioBrickTM formatted plasmid. Results. All

  6. Diversification of AID/APOBEC-like deaminases in metazoa: multiplicity of clades and widespread roles in immunity.

    Science.gov (United States)

    Krishnan, Arunkumar; Iyer, Lakshminarayan M; Holland, Stephen J; Boehm, Thomas; Aravind, L

    2018-04-03

    AID/APOBEC deaminases (AADs) convert cytidine to uridine in single-stranded nucleic acids. They are involved in numerous mutagenic processes, including those underpinning vertebrate innate and adaptive immunity. Using a multipronged sequence analysis strategy, we uncover several AADs across metazoa, dictyosteliida, and algae, including multiple previously unreported vertebrate clades, and versions from urochordates, nematodes, echinoderms, arthropods, lophotrochozoans, cnidarians, and porifera. Evolutionary analysis suggests a fundamental division of AADs early in metazoan evolution into secreted deaminases (SNADs) and classical AADs, followed by diversification into several clades driven by rapid-sequence evolution, gene loss, lineage-specific expansions, and lateral transfer to various algae. Most vertebrate AADs, including AID and APOBECs1-3, diversified in the vertebrates, whereas the APOBEC4-like clade has a deeper origin in metazoa. Positional entropy analysis suggests that several AAD clades are diversifying rapidly, especially in the positions predicted to interact with the nucleic acid target motif, and with potential viral inhibitors. Further, several AADs have evolved neomorphic metal-binding inserts, especially within loops predicted to interact with the target nucleic acid. We also observe polymorphisms, driven by alternative splicing, gene loss, and possibly intergenic recombination between paralogs. We propose that biological conflicts of AADs with viruses and genomic retroelements are drivers of rapid AAD evolution, suggesting a widespread presence of mutagenesis-based immune-defense systems. Deaminases like AID represent versions "institutionalized" from the broader array of AADs pitted in such arms races for mutagenesis of self-DNA, and similar recruitment might have independently occurred elsewhere in metazoa. Copyright © 2018 the Author(s). Published by PNAS.

  7. Genotyping of Brucella species using clade specific SNPs

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    Foster Jeffrey T

    2012-06-01

    Full Text Available Abstract Background Brucellosis is a worldwide disease of mammals caused by Alphaproteobacteria in the genus Brucella. The genus is genetically monomorphic, requiring extensive genotyping to differentiate isolates. We utilized two different genotyping strategies to characterize isolates. First, we developed a microarray-based assay based on 1000 single nucleotide polymorphisms (SNPs that were identified from whole genome comparisons of two B. abortus isolates , one B. melitensis, and one B. suis. We then genotyped a diverse collection of 85 Brucella strains at these SNP loci and generated a phylogenetic tree of relationships. Second, we developed a selective primer-extension assay system using capillary electrophoresis that targeted 17 high value SNPs across 8 major branches of the phylogeny and determined their genotypes in a large collection ( n = 340 of diverse isolates. Results Our 1000 SNP microarray readily distinguished B. abortus, B. melitensis, and B. suis, differentiating B. melitensis and B. suis into two clades each. Brucella abortus was divided into four major clades. Our capillary-based SNP genotyping confirmed all major branches from the microarray assay and assigned all samples to defined lineages. Isolates from these lineages and closely related isolates, among the most commonly encountered lineages worldwide, can now be quickly and easily identified and genetically characterized. Conclusions We have identified clade-specific SNPs in Brucella that can be used for rapid assignment into major groups below the species level in the three main Brucella species. Our assays represent SNP genotyping approaches that can reliably determine the evolutionary relationships of bacterial isolates without the need for whole genome sequencing of all isolates.

  8. Meiotic Clade AAA ATPases: Protein Polymer Disassembly Machines.

    Science.gov (United States)

    Monroe, Nicole; Hill, Christopher P

    2016-05-08

    Meiotic clade AAA ATPases (ATPases associated with diverse cellular activities), which were initially grouped on the basis of phylogenetic classification of their AAA ATPase cassette, include four relatively well characterized family members, Vps4, spastin, katanin and fidgetin. These enzymes all function to disassemble specific polymeric protein structures, with Vps4 disassembling the ESCRT-III polymers that are central to the many membrane-remodeling activities of the ESCRT (endosomal sorting complexes required for transport) pathway and spastin, katanin p60 and fidgetin affecting multiple aspects of cellular dynamics by severing microtubules. They share a common domain architecture that features an N-terminal MIT (microtubule interacting and trafficking) domain followed by a single AAA ATPase cassette. Meiotic clade AAA ATPases function as hexamers that can cycle between the active assembly and inactive monomers/dimers in a regulated process, and they appear to disassemble their polymeric substrates by translocating subunits through the central pore of their hexameric ring. Recent studies with Vps4 have shown that nucleotide-induced asymmetry is a requirement for substrate binding to the pore loops and that recruitment to the protein lattice via MIT domains also relieves autoinhibition and primes the AAA ATPase cassettes for substrate binding. The most striking, unifying feature of meiotic clade AAA ATPases may be their MIT domain, which is a module that is found in a wide variety of proteins that localize to ESCRT-III polymers. Spastin also displays an adjacent microtubule binding sequence, and the presence of both ESCRT-III and microtubule binding elements may underlie the recent findings that the ESCRT-III disassembly function of Vps4 and the microtubule-severing function of spastin, as well as potentially katanin and fidgetin, are highly coordinated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Analysis of C. elegans NR2E nuclear receptors defines three conserved clades and ligand-independent functions

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    Weber Katherine P

    2012-06-01

    Full Text Available Abstract Background The nuclear receptors (NRs are an important class of transcription factors that are conserved across animal phyla. Canonical NRs consist of a DNA-binding domain (DBD and ligand-binding domain (LBD. While most animals have 20–40 NRs, nematodes of the genus Caenorhabditis have experienced a spectacular proliferation and divergence of NR genes. The LBDs of evolutionarily-conserved Caenorhabditis NRs have diverged sharply from their Drosophila and vertebrate orthologs, while the DBDs have been strongly conserved. The NR2E family of NRs play critical roles in development, especially in the nervous system. In this study, we explore the phylogenetics and function of the NR2E family of Caenorhabditis elegans, using an in vivo assay to test LBD function. Results Phylogenetic analysis reveals that the NR2E family of NRs consists of three broadly-conserved clades of orthologous NRs. In C. elegans, these clades are defined by nhr-67, fax-1 and nhr-239. The vertebrate orthologs of nhr-67 and fax-1 are Tlx and PNR, respectively. While the nhr-239 clade includes orthologs in insects (Hr83, an echinoderm, and a hemichordate, the gene appears to have been lost from vertebrate lineages. The C. elegans and C. briggsae nhr-239 genes have an apparently-truncated and highly-diverged LBD region. An additional C. elegans NR2E gene, nhr-111, appears to be a recently-evolved paralog of fax-1; it is present in C. elegans, but not C. briggsae or other animals with completely-sequenced genomes. Analysis of the relatively unstudied nhr-111 and nhr-239 genes demonstrates that they are both expressed—nhr-111 very broadly and nhr-239 in a small subset of neurons. Analysis of the FAX-1 LBD in an in vivo assay revealed that it is not required for at least some developmental functions. Conclusions Our analysis supports three conserved clades of NR2E receptors, only two of which are represented in vertebrates, indicating three ancestral NR2E genes in the

  10. Decoupled form and function in disparate herbivorous dinosaur clades

    Science.gov (United States)

    Lautenschlager, Stephan; Brassey, Charlotte A.; Button, David J.; Barrett, Paul M.

    2016-05-01

    Convergent evolution, the acquisition of morphologically similar traits in unrelated taxa due to similar functional demands or environmental factors, is a common phenomenon in the animal kingdom. Consequently, the occurrence of similar form is used routinely to address fundamental questions in morphofunctional research and to infer function in fossils. However, such qualitative assessments can be misleading and it is essential to test form/function relationships quantitatively. The parallel occurrence of a suite of morphologically convergent craniodental characteristics in three herbivorous, phylogenetically disparate dinosaur clades (Sauropodomorpha, Ornithischia, Theropoda) provides an ideal test case. A combination of computational biomechanical models (Finite Element Analysis, Multibody Dynamics Analysis) demonstrate that despite a high degree of morphological similarity between representative taxa (Plateosaurus engelhardti, Stegosaurus stenops, Erlikosaurus andrewsi) from these clades, their biomechanical behaviours are notably different and difficult to predict on the basis of form alone. These functional differences likely reflect dietary specialisations, demonstrating the value of quantitative biomechanical approaches when evaluating form/function relationships in extinct taxa.

  11. Quantifying variation in speciation and extinction rates with clade data.

    Science.gov (United States)

    Paradis, Emmanuel; Tedesco, Pablo A; Hugueny, Bernard

    2013-12-01

    High-level phylogenies are very common in evolutionary analyses, although they are often treated as incomplete data. Here, we provide statistical tools to analyze what we name "clade data," which are the ages of clades together with their numbers of species. We develop a general approach for the statistical modeling of variation in speciation and extinction rates, including temporal variation, unknown variation, and linear and nonlinear modeling. We show how this approach can be generalized to a wide range of situations, including testing the effects of life-history traits and environmental variables on diversification rates. We report the results of an extensive simulation study to assess the performance of some statistical tests presented here as well as of the estimators of speciation and extinction rates. These latter results suggest the possibility to estimate correctly extinction rate in the absence of fossils. An example with data on fish is presented. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  12. Decoupled form and function in disparate herbivorous dinosaur clades.

    Science.gov (United States)

    Lautenschlager, Stephan; Brassey, Charlotte A; Button, David J; Barrett, Paul M

    2016-05-20

    Convergent evolution, the acquisition of morphologically similar traits in unrelated taxa due to similar functional demands or environmental factors, is a common phenomenon in the animal kingdom. Consequently, the occurrence of similar form is used routinely to address fundamental questions in morphofunctional research and to infer function in fossils. However, such qualitative assessments can be misleading and it is essential to test form/function relationships quantitatively. The parallel occurrence of a suite of morphologically convergent craniodental characteristics in three herbivorous, phylogenetically disparate dinosaur clades (Sauropodomorpha, Ornithischia, Theropoda) provides an ideal test case. A combination of computational biomechanical models (Finite Element Analysis, Multibody Dynamics Analysis) demonstrate that despite a high degree of morphological similarity between representative taxa (Plateosaurus engelhardti, Stegosaurus stenops, Erlikosaurus andrewsi) from these clades, their biomechanical behaviours are notably different and difficult to predict on the basis of form alone. These functional differences likely reflect dietary specialisations, demonstrating the value of quantitative biomechanical approaches when evaluating form/function relationships in extinct taxa.

  13. Antigenic Variation in H5N1 clade 2.1 Viruses in Indonesia from 2005 to 2011

    Directory of Open Access Journals (Sweden)

    Vivi Setiawaty

    2013-01-01

    Full Text Available Influenza A (H5N1 virus, has spread to several countries in the world and has a high mortality rate. Meanwhile, the virus has evolved into several clades. The human influenza A (H5N1 virus circulating in Indonesia is a member of clade 2.1, which is different in antigenicity from other clades of influenza A (H5N1. An analysis of the antigenic variation in the H5 hemagglutinin gene (HA of the influenza A (H5N1 virus strains circulating in Indonesia has been undertaken. Several position of amino acid mutations, including mutations at positions 35, 53, 141, 145, 163, 174, 183, 184, 189, and 231, have been identified. The mutation Val-174-Iso appears to play an important role in immunogenicity and cross-reactivity with rabbit antisera. This study shows that the evolution of the H5HA antigenic variation of the influenza A (H5N1 virus circulating in Indonesia from 2005 to 2011 may affect the immunogenicity of the virus.

  14. Phylogenomics reveals rapid, simultaneous diversification of three major clades of Gondwanan frogs at the Cretaceous-Paleogene boundary.

    Science.gov (United States)

    Feng, Yan-Jie; Blackburn, David C; Liang, Dan; Hillis, David M; Wake, David B; Cannatella, David C; Zhang, Peng

    2017-07-18

    Frogs (Anura) are one of the most diverse groups of vertebrates and comprise nearly 90% of living amphibian species. Their worldwide distribution and diverse biology make them well-suited for assessing fundamental questions in evolution, ecology, and conservation. However, despite their scientific importance, the evolutionary history and tempo of frog diversification remain poorly understood. By using a molecular dataset of unprecedented size, including 88-kb characters from 95 nuclear genes of 156 frog species, in conjunction with 20 fossil-based calibrations, our analyses result in the most strongly supported phylogeny of all major frog lineages and provide a timescale of frog evolution that suggests much younger divergence times than suggested by earlier studies. Unexpectedly, our divergence-time analyses show that three species-rich clades (Hyloidea, Microhylidae, and Natatanura), which together comprise ∼88% of extant anuran species, simultaneously underwent rapid diversification at the Cretaceous-Paleogene (K-Pg) boundary (KPB). Moreover, anuran families and subfamilies containing arboreal species originated near or after the KPB. These results suggest that the K-Pg mass extinction may have triggered explosive radiations of frogs by creating new ecological opportunities. This phylogeny also reveals relationships such as Microhylidae being sister to all other ranoid frogs and African continental lineages of Natatanura forming a clade that is sister to a clade of Eurasian, Indian, Melanesian, and Malagasy lineages. Biogeographical analyses suggest that the ancestral area of modern frogs was Africa, and their current distribution is largely associated with the breakup of Pangaea and subsequent Gondwanan fragmentation.

  15. Molecular exploration of hidden diversity in the Indo-West Pacific sciaenid clade.

    Science.gov (United States)

    Lo, Pei-Chun; Liu, Shu-Hui; Nor, Siti Azizah Mohd; Chen, Wei-Jen

    2017-01-01

    The family Sciaenidae, known as croakers or drums, is one of the largest perciform fish families. A recent multi-gene based study investigating the phylogeny and biogeography of global sciaenids revealed that the origin and early diversification of this family occurred in tropical America during the Late Oligocene-Early Miocene before undergoing range expansions to other seas including the Indo-West Pacific, where high species richness is observed. Despite this clarification of the overall evolutionary history of the family, knowledge of the taxonomy and phylogeny of sciaenid genera endemic to the Indo-West Pacific is still limited due to lack of a thorough survey of all taxa. In this study, we used DNA-based approaches to investigate the evolutionary relationships, to explore the species diversity, and to elucidate the taxonomic status of sciaenid species/genera within the Indo-West Pacific clade. Three datasets were herein built for the above objectives: the combined dataset (248 samples from 45 currently recognized species) from one nuclear gene (RAG1) and one mitochondrial gene (COI); the dataset with only RAG1 gene sequences (245 samples from 44 currently recognized species); and the dataset with only COI gene sequences (308 samples from 51 currently recognized species). The latter was primarily used for our biodiversity exploration with two different species delimitation methods (Automatic Barcode Gap Discovery, ABGD and Generalized Mixed Yule Coalescent, GMYC). The results were further evaluated with help of four supplementary criteria for species delimitation (genetic similarity, monophyly inferred from individual gene and combined data trees, geographic distribution, and morphology). Our final results confirmed the validity of 32 currently recognized species and identified several potential new species waiting for formal descriptions. We also reexamined the taxonomic status of the genera, Larimichthys, Nibea, Protonibea and Megalonibea, and suggested a

  16. Molecular exploration of hidden diversity in the Indo-West Pacific sciaenid clade.

    Directory of Open Access Journals (Sweden)

    Pei-Chun Lo

    Full Text Available The family Sciaenidae, known as croakers or drums, is one of the largest perciform fish families. A recent multi-gene based study investigating the phylogeny and biogeography of global sciaenids revealed that the origin and early diversification of this family occurred in tropical America during the Late Oligocene-Early Miocene before undergoing range expansions to other seas including the Indo-West Pacific, where high species richness is observed. Despite this clarification of the overall evolutionary history of the family, knowledge of the taxonomy and phylogeny of sciaenid genera endemic to the Indo-West Pacific is still limited due to lack of a thorough survey of all taxa. In this study, we used DNA-based approaches to investigate the evolutionary relationships, to explore the species diversity, and to elucidate the taxonomic status of sciaenid species/genera within the Indo-West Pacific clade. Three datasets were herein built for the above objectives: the combined dataset (248 samples from 45 currently recognized species from one nuclear gene (RAG1 and one mitochondrial gene (COI; the dataset with only RAG1 gene sequences (245 samples from 44 currently recognized species; and the dataset with only COI gene sequences (308 samples from 51 currently recognized species. The latter was primarily used for our biodiversity exploration with two different species delimitation methods (Automatic Barcode Gap Discovery, ABGD and Generalized Mixed Yule Coalescent, GMYC. The results were further evaluated with help of four supplementary criteria for species delimitation (genetic similarity, monophyly inferred from individual gene and combined data trees, geographic distribution, and morphology. Our final results confirmed the validity of 32 currently recognized species and identified several potential new species waiting for formal descriptions. We also reexamined the taxonomic status of the genera, Larimichthys, Nibea, Protonibea and Megalonibea, and

  17. Draft genome sequence of marine alphaproteobacterial strain HIMB11, the first cultivated representative of a unique lineage within the Roseobacter clade possessing an unusually small genome.

    Science.gov (United States)

    Durham, Bryndan P; Grote, Jana; Whittaker, Kerry A; Bender, Sara J; Luo, Haiwei; Grim, Sharon L; Brown, Julia M; Casey, John R; Dron, Antony; Florez-Leiva, Lennin; Krupke, Andreas; Luria, Catherine M; Mine, Aric H; Nigro, Olivia D; Pather, Santhiska; Talarmin, Agathe; Wear, Emma K; Weber, Thomas S; Wilson, Jesse M; Church, Matthew J; DeLong, Edward F; Karl, David M; Steward, Grieg F; Eppley, John M; Kyrpides, Nikos C; Schuster, Stephan; Rappé, Michael S

    2014-06-15

    Strain HIMB11 is a planktonic marine bacterium isolated from coastal seawater in Kaneohe Bay, Oahu, Hawaii belonging to the ubiquitous and versatile Roseobacter clade of the alphaproteobacterial family Rhodobacteraceae. Here we describe the preliminary characteristics of strain HIMB11, including annotation of the draft genome sequence and comparative genomic analysis with other members of the Roseobacter lineage. The 3,098,747 bp draft genome is arranged in 34 contigs and contains 3,183 protein-coding genes and 54 RNA genes. Phylogenomic and 16S rRNA gene analyses indicate that HIMB11 represents a unique sublineage within the Roseobacter clade. Comparison with other publicly available genome sequences from members of the Roseobacter lineage reveals that strain HIMB11 has the genomic potential to utilize a wide variety of energy sources (e.g. organic matter, reduced inorganic sulfur, light, carbon monoxide), while possessing a reduced number of substrate transporters.

  18. A Ser29Leu substitution in the cytosine deaminase Fca1p is responsible for clade-specific flucytosine resistance in Candida dubliniensis.

    LENUS (Irish Health Repository)

    McManus, Brenda A

    2009-11-01

    The population structure of the opportunistic yeast pathogen Candida dubliniensis is composed of three main multilocus sequence typing clades (clades C1 to C3), and clade C3 predominantly consists of isolates from the Middle East that exhibit high-level resistance (MIC(50) > or = 128 microg\\/ml) to the fungicidal agent flucytosine (5FC). The close relative of C. dubliniensis, C. albicans, also exhibits clade-specific resistance to 5FC, and resistance is most commonly mediated by an Arg101Cys substitution in the FUR1 gene encoding uracil phosphoribosyltransferase. Broth microdilution assays with fluorouracil (5FU), the toxic deaminated form of 5FC, showed that both 5FC-resistant and 5FC-susceptible C. dubliniensis isolates exhibited similar 5FU MICs, suggesting that the C. dubliniensis cytosine deaminase (Fca1p) encoded by C. dubliniensis FCA1 (CdFCA1) may play a role in mediating C. dubliniensis clade-specific 5FC resistance. Amino acid sequence analysis of the CdFCA1 open reading frame (ORF) identified a homozygous Ser29Leu substitution in all 12 5FC-resistant isolates investigated which was not present in any of the 9 5FC-susceptible isolates examined. The tetracycline-inducible expression of the CdFCA1 ORF from a 5FC-susceptible C. dubliniensis isolate in two separate 5FC-resistant clade C3 isolates restored susceptibility to 5FC, demonstrating that the Ser29Leu substitution was responsible for the clade-specific 5FC resistance and that the 5FC resistance encoded by FCA1 genes with the Ser29Leu transition is recessive. Quantitative real-time PCR analysis showed no significant difference in CdFCA1 expression between 5FC-susceptible and 5FC-resistant isolates in either the presence or the absence of subinhibitory concentrations of 5FC, suggesting that the Ser29Leu substitution in the CdFCA1 ORF is the sole cause of 5FC resistance in clade C3 C. dubliniensis isolates.

  19. Investigation of the Genetics and Biochemistry of Roseobacticide Production in the Roseobacter Clade Bacterium Phaeobacter inhibens

    Directory of Open Access Journals (Sweden)

    Rurun Wang

    2016-03-01

    Full Text Available Roseobacter clade bacteria are abundant in surface waters and are among the most metabolically diverse and ecologically significant species. This group includes opportunistic symbionts that associate with micro- and macroalgae. We have proposed that one representative member, Phaeobacter inhibens, engages in a dynamic symbiosis with the microalga Emiliania huxleyi. In one phase, mutualistically beneficial molecules are exchanged, including the Roseobacter-produced antibiotic tropodithietic acid (TDA, which is thought to protect the symbiotic interaction. In an alternative parasitic phase, triggered by algal senescence, the bacteria produce potent algaecides, the roseobacticides, which kill the algal host. Here, we employed genetic and biochemical screens to identify the roseobacticide biosynthetic gene cluster. By using a transposon mutagenesis approach, we found that genes required for TDA synthesis—the tda operon and paa catabolon—are also necessary for roseobacticide production. Thus, in contrast to the one-cluster–one-compound paradigm, the tda gene cluster can generate two sets of molecules with distinct structures and bioactivities. We further show that roseobacticide production is quorum sensing regulated via an N-acyl homoserine lactone signal (3-OH–C10-HSL. To ensure tight regulation of algaecide production, and thus of a lifestyle switch from mutualism to parasitism, roseobacticide biosynthesis necessitates the presence of both an algal senescence molecule and a quorum sensing signal.

  20. Emergence of multiple clade 2.3.2.1 influenza A (H5N1) virus subgroups in Vietnam and detection of novel reassortants.

    Science.gov (United States)

    Creanga, Adrian; Thi Nguyen, Diep; Gerloff, Nancy; Thi Do, Hoa; Balish, Amanda; Dang Nguyen, Hoang; Jang, Yunho; Thi Dam, Vui; Thor, Sharmi; Jones, Joyce; Simpson, Natosha; Shu, Bo; Emery, Shannon; Berman, LaShondra; Nguyen, Ha T; Bryant, Juliet E; Lindstrom, Steve; Klimov, Alexander; Donis, Ruben O; Davis, C Todd; Nguyen, Tung

    2013-09-01

    Phylogenetic analyses of 169 influenza A(H5N1) virus genomes were conducted for samples collected through active surveillance and outbreak responses in Vietnam between September 2010 and September 2012. While clade 1.1 viruses persisted in southern regions, three genetically distinct subgroups of clade 2.3.2.1 were found in northern and central Vietnam. The identification of each subgroup corresponded with detection of novel reassortants, likely due to their overlapping circulation throughout the country. While the previously identified clade 1.1 and A/Hubei/1/2010-like 2.3.2.1 genotypes remained the predominant viruses detected, four viruses were found to be reassortants between A/Hubei/1/2010-like (HA, NA, PB2, PB1, PA, NP) and A/duck/Vietnam/NCVD-885/2010-like (M, NS) viruses and one virus was identified as having A/duck/Vietnam/NCVD-885/2010-like HA, NA, PB1, and NP with A/Hubei/1/2010-like PB2 and PA genes. Additionally, clade 2.3.2.1 A/Hong Kong/6841/2010-like viruses, first detected in mid-2012, were identified as reassortants comprised of A/Hubei/1/2010-like PB2 and PA and A/duck/Vietnam/NCVD-885/2010-like PB1, NP, NA, M, NS genes. Published by Elsevier Inc.

  1. High-throughput proteogenomics of Ruegeria pomeroyi: seeding a better genomic annotation for the whole marine Roseobacter clade

    Directory of Open Access Journals (Sweden)

    Christie-Oleza Joseph A

    2012-02-01

    Full Text Available Abstract Background The structural and functional annotation of genomes is now heavily based on data obtained using automated pipeline systems. The key for an accurate structural annotation consists of blending similarities between closely related genomes with biochemical evidence of the genome interpretation. In this work we applied high-throughput proteogenomics to Ruegeria pomeroyi, a member of the Roseobacter clade, an abundant group of marine bacteria, as a seed for the annotation of the whole clade. Results A large dataset of peptides from R. pomeroyi was obtained after searching over 1.1 million MS/MS spectra against a six-frame translated genome database. We identified 2006 polypeptides, of which thirty-four were encoded by open reading frames (ORFs that had not previously been annotated. From the pool of 'one-hit-wonders', i.e. those ORFs specified by only one peptide detected by tandem mass spectrometry, we could confirm the probable existence of five additional new genes after proving that the corresponding RNAs were transcribed. We also identified the most-N-terminal peptide of 486 polypeptides, of which sixty-four had originally been wrongly annotated. Conclusions By extending these re-annotations to the other thirty-six Roseobacter isolates sequenced to date (twenty different genera, we propose the correction of the assigned start codons of 1082 homologous genes in the clade. In addition, we also report the presence of novel genes within operons encoding determinants of the important tricarboxylic acid cycle, a feature that seems to be characteristic of some Roseobacter genomes. The detection of their corresponding products in large amounts raises the question of their function. Their discoveries point to a possible theory for protein evolution that will rely on high expression of orphans in bacteria: their putative poor efficiency could be counterbalanced by a higher level of expression. Our proteogenomic analysis will increase

  2. Barcoding success as a function of phylogenetic relatedness in Viburnum, a clade of woody angiosperms

    Directory of Open Access Journals (Sweden)

    Clement Wendy L

    2012-05-01

    Full Text Available Abstract Background The chloroplast genes matK and rbcL have been proposed as a “core” DNA barcode for identifying plant species. Published estimates of successful species identification using these loci (70-80% may be inflated because they may have involved comparisons among distantly related species within target genera. To assess the ability of the proposed two-locus barcode to discriminate closely related species, we carried out a hierarchically structured set of comparisons within Viburnum, a clade of woody angiosperms containing ca. 170 species (some 70 of which are currently used in horticulture. For 112 Viburnum species, we evaluated rbcL + matK, as well as the chloroplast regions rpl32-trnL, trnH-psbA, trnK, and the nuclear ribosomal internal transcribed spacer region (nrITS. Results At most, rbcL + matK could discriminate 53% of all Viburnum species, with only 18% of the comparisons having genetic distances >1%. When comparisons were progressively restricted to species within major Viburnum subclades, there was a significant decrease in both the discriminatory power and the genetic distances. trnH-psbA and nrITS show much higher levels of variation and potential discriminatory power, and their use in plant barcoding should be reconsidered. As barcoding has often been used to discriminate species within local areas, we also compared Viburnum species within two regions, Japan and Mexico and Central America. Greater success in discriminating among the Japanese species reflects the deeper evolutionary history of Viburnum in that area, as compared to the recent radiation of a single clade into the mountains of Latin America. Conclusions We found very low levels of discrimination among closely related species of Viburnum, and low levels of variation in the proposed barcoding loci may limit success within other clades of long-lived woody plants. Inclusion of the supplementary barcodes trnH-psbA and nrITS increased discrimination rates but

  3. Roseobacter-clade bacteria as probiotics in marine larvaeculture

    DEFF Research Database (Denmark)

    Grotkjær, Torben

    Disease caused by fish pathogenic bacteria can cause large scale crashes in marine fish larval rearing units. One of the biggest challenges for aquaculture is the management of these bacterial outbreaks. Vaccines can be admitted to fish but only the juvenile and the adult fish because they need...... to have a mature immune system. This means that the larvae of the fish, until they are 2-3 weeks old are more prone to bacterial infections. A short term solution is antibiotics but this leaves way for the selection for antibiotic resistance among the pathogenic bacteria, which again can be transferred...... to human pathogens. Alternatives are therefore needed and one could be the use of probiotic bacteria. Marine bacteria from the Roseobacter clade (Phaeobacter inhibens) have shown great potential as probiotic bacteria, and we have hypothesized that they could be used to antagonize pathogenic fish...

  4. Characterization of the denitrification-associated phosphorus uptake properties of "Candidatus Accumulibacter phosphatis" clades in sludge subjected to enhanced biological phosphorus removal.

    Science.gov (United States)

    Kim, Jeong Myeong; Lee, Hyo Jung; Lee, Dae Sung; Jeon, Che Ok

    2013-03-01

    To characterize the denitrifying phosphorus (P) uptake properties of "Candidatus Accumulibacter phosphatis," a sequencing batch reactor (SBR) was operated with acetate. The SBR operation was gradually acclimated from anaerobic-oxic (AO) to anaerobic-anoxic-oxic (A2O) conditions by stepwise increases of nitrate concentration and the anoxic time. The communities of "Ca. Accumulibacter" and associated bacteria at the initial (AO) and final (A2O) stages were compared using 16S rRNA and polyphosphate kinase genes and using fluorescence in situ hybridization (FISH). The acclimation process led to a clear shift in the relative abundances of recognized "Ca. Accumulibacter" subpopulations from clades IIA > IA > IIF to clades IIC > IA > IIF, as well as to increases in the abundance of other associated bacteria (Dechloromonas [from 1.2% to 19.2%] and "Candidatus Competibacter phosphatis" [from 16.4% to 20.0%]), while the overall "Ca. Accumulibacter" abundance decreased (from 55.1% to 29.2%). A series of batch experiments combined with FISH/microautoradiography (MAR) analyses was performed to characterize the denitrifying P uptake properties of the "Ca. Accumulibacter" clades. In FISH/MAR experiments using slightly diluted sludge (∼0.5 g/liter), all "Ca. Accumulibacter" clades successfully took up phosphorus in the presence of nitrate. However, the "Ca. Accumulibacter" clades showed no P uptake in the presence of nitrate when the sludge was highly diluted (∼0.005 g/liter); under these conditions, reduction of nitrate to nitrite did not occur, whereas P uptake by "Ca. Accumulibacter" clades occurred when nitrite was added. These results suggest that the "Ca. Accumulibacter" cells lack nitrate reduction capabilities and that P uptake by "Ca. Accumulibacter" is dependent upon nitrite generated by associated nitrate-reducing bacteria such as Dechloromonas and "Ca. Competibacter."

  5. Glossina palpalis palpalis populations from Equatorial Guinea belong to distinct allopatric clades.

    Science.gov (United States)

    Cordon-Obras, Carlos; Cano, Jorge; Knapp, Jenny; Nebreda, Paloma; Ndong-Mabale, Nicolas; Ncogo-Ada, Policarpo Ricardo; Ndongo-Asumu, Pedro; Navarro, Miguel; Pinto, Joao; Benito, Agustin; Bart, Jean-Mathieu

    2014-01-17

    Luba is one of the four historical foci of Human African Trypanosomiasis (HAT) on Bioko Island, in Equatorial Guinea. Although no human cases have been detected since 1995, T. b. gambiense was recently observed in the vector Glossina palpalis palpalis. The existence of cryptic species within this vector taxon has been previously suggested, although no data are available regarding the evolutionary history of tsetse flies populations in Bioko. A phylogenetic analysis of 60 G. p. palpalis from Luba was performed sequencing three mitochondrial (COI, ND2 and 16S) and one nuclear (rDNA-ITS1) DNA markers. Phylogeny reconstruction was performed by Distance Based, Maximum Likelihood and Bayesian Inference methods. The COI and ND2 mitochondrial genes were concatenated and revealed 10 closely related haplotypes with a dominant one found in 61.1% of the flies. The sequence homology of the other 9 haplotypes compared to the former ranged from 99.6 to 99.9%. Phylogenetic analysis clearly clustered all island samples with flies coming from the Western African Clade (WAC), and separated from the flies belonging to the Central Africa Clade (CAC), including samples from Mbini and Kogo, two foci of mainland Equatorial Guinea. Consistent with mitochondrial data, analysis of the microsatellite motif present in the ITS1 sequence exhibited two closely related genotypes, clearly divergent from the genotypes previously identified in Mbini and Kogo. We report herein that tsetse flies populations circulating in Equatorial Guinea are composed of two allopatric subspecies, one insular and the other continental. The presence of these two G. p. palpalis cryptic taxa in Equatorial Guinea should be taken into account to accurately manage vector control strategy, in a country where trypanosomiasis transmission is controlled but not definitively eliminated yet.

  6. Phylogenetic signal in the acoustic parameters of the advertisement calls of four clades of anurans.

    Science.gov (United States)

    Gingras, Bruno; Mohandesan, Elmira; Boko, Drasko; Fitch, W Tecumseh

    2013-07-01

    Anuran vocalizations, especially their advertisement calls, are largely species-specific and can be used to identify taxonomic affiliations. Because anurans are not vocal learners, their vocalizations are generally assumed to have a strong genetic component. This suggests that the degree of similarity between advertisement calls may be related to large-scale phylogenetic relationships. To test this hypothesis, advertisement calls from 90 species belonging to four large clades (Bufo, Hylinae, Leptodactylus, and Rana) were analyzed. Phylogenetic distances were estimated based on the DNA sequences of the 12S mitochondrial ribosomal RNA gene, and, for a subset of 49 species, on the rhodopsin gene. Mean values for five acoustic parameters (coefficient of variation of root-mean-square amplitude, dominant frequency, spectral flux, spectral irregularity, and spectral flatness) were computed for each species. We then tested for phylogenetic signal on the body-size-corrected residuals of these five parameters, using three statistical tests (Moran's I, Mantel, and Blomberg's K) and three models of genetic distance (pairwise distances, Abouheif's proximities, and the variance-covariance matrix derived from the phylogenetic tree). A significant phylogenetic signal was detected for most acoustic parameters on the 12S dataset, across statistical tests and genetic distance models, both for the entire sample of 90 species and within clades in several cases. A further analysis on a subset of 49 species using genetic distances derived from rhodopsin and from 12S broadly confirmed the results obtained on the larger sample, indicating that the phylogenetic signals observed in these acoustic parameters can be detected using a variety of genetic distance models derived either from a variable mitochondrial sequence or from a conserved nuclear gene. We found a robust relationship, in a large number of species, between anuran phylogenetic relatedness and acoustic similarity in the

  7. Deep divergences and extensive phylogeographic structure in a clade of lowland tropical salamanders

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    Rovito Sean M

    2012-12-01

    Full Text Available Abstract Background The complex geological history of Mesoamerica provides the opportunity to study the impact of multiple biogeographic barriers on population differentiation. We examine phylogeographic patterns in a clade of lowland salamanders (Bolitoglossa subgenus Nanotriton using two mitochondrial genes and one nuclear gene. We use several phylogeographic analyses to infer the history of this clade and test hypotheses regarding the geographic origin of species and location of genetic breaks within species. We compare our results to those for other taxa to determine if historical events impacted different species in a similar manner. Results Deep genetic divergence between species indicates that they are relatively old, and two of the three widespread species show strong phylogeographic structure. Comparison of mtDNA and nuclear gene trees shows no evidence of hybridization or introgression between species. Isolated populations of Bolitoglossa rufescens from Los Tuxtlas region constitute a separate lineage based on molecular data and morphology, and divergence between Los Tuxtlas and other areas appears to predate the arrival of B. rufescens in other areas west of the Isthmus of Tehuantepec. The Isthmus appears responsible for Pliocene vicariance within B. rufescens, as has been shown for other taxa. The Motagua-Polochic fault system does not appear to have caused population vicariance, unlike in other systems. Conclusions Species of Nanotriton have responded to some major geological events in the same manner as other taxa, particularly in the case of the Isthmus of Tehuantepec. The deep divergence of the Los Tuxtlas populations of B. rufescens from other populations highlights the contribution of this volcanic system to patterns of regional endemism, and morphological differences observed in the Los Tuxtlas populations suggests that they may represent an undescribed species of Bolitoglossa. The absence of phylogeographic structure in B

  8. Origin and diversification of major clades in parmelioid lichens (Parmeliaceae, Ascomycota during the Paleogene inferred by Bayesian analysis.

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    Guillermo Amo de Paz

    Full Text Available There is a long-standing debate on the extent of vicariance and long-distance dispersal events to explain the current distribution of organisms, especially in those with small diaspores potentially prone to long-distance dispersal. Age estimates of clades play a crucial role in evaluating the impact of these processes. The aim of this study is to understand the evolutionary history of the largest clade of macrolichens, the parmelioid lichens (Parmeliaceae, Lecanoromycetes, Ascomycota by dating the origin of the group and its major lineages. They have a worldwide distribution with centers of distribution in the Neo- and Paleotropics, and semi-arid subtropical regions of the Southern Hemisphere. Phylogenetic analyses were performed using DNA sequences of nuLSU and mtSSU rDNA, and the protein-coding RPB1 gene. The three DNA regions had different evolutionary rates: RPB1 gave a rate two to four times higher than nuLSU and mtSSU. Divergence times of the major clades were estimated with partitioned BEAST analyses allowing different rates for each DNA region and using a relaxed clock model. Three calibrations points were used to date the tree: an inferred age at the stem of Lecanoromycetes, and two dated fossils: Parmelia in the parmelioid group, and Alectoria. Palaeoclimatic conditions and the palaeogeological area cladogram were compared to the dated phylogeny of parmelioid. The parmelioid group diversified around the K/T boundary, and the major clades diverged during the Eocene and Oligocene. The radiation of the genera occurred through globally changing climatic condition of the early Oligocene, Miocene and early Pliocene. The estimated divergence times are consistent with long-distance dispersal events being the major factor to explain the biogeographical distribution patterns of Southern Hemisphere parmelioids, especially for Africa-Australia disjunctions, because the sequential break-up of Gondwana started much earlier than the origin of these

  9. Phylogenetic analysis of Melon chlorotic leaf curl virus from Guatemala: Another emergent species in the Squash leaf curl virus clade

    KAUST Repository

    Brown, J.K.

    2011-06-01

    The genome of a new bipartite begomovirus Melon chlorotic leaf curl virus from Guatemala (MCLCuV-GT) was cloned and the genome sequence was determined. The virus causes distinct symptoms on melons that were not previously observed in melon crops in Guatemala or elsewhere. Phylogenetic analysis of MCLCuV-GT and begomoviruses infecting cucurbits and other host plant species indicated that its closest relative was MCLCuV from Costa Rica (MCLCuV-CR). The DNA-A components of two isolates shared 88.8% nucleotide identity, making them strains of the same species. Further, both MCLCuV-GT and MCLCuV-CR grouped with other Western Hemisphere cucurbit-infecting species in the SLCV-clade making them the most southerly cucurbit-infecting members of the clade to date. Although the common region of the cognate components of MCLCuV-GT and MCLCuV-CR, shared similar to 96.3% nucleotide identity. While DNA-A and DNA-B components of MCLCuV-GT were less than 86% nucleotide identity with the respective DNAA and DNA-B common regions of MCLCuV-CR. The late viral genes of the two strains shared the least nt identity (<88%) while their early genes shared the highest nt identity (>90%). The collective evidence suggests that these two strains of MCLCuV are evolutionarily divergent owing in part to recombination, but also due to the accumulation of a substantial number of mutations. In addition they are differentially host-adapted, as has been documented for other cucurbit-infecting, bean-adapted, species in the SLCV clade. (C) 2011 Elsevier B.V. All rights reserved.

  10. Molecular Characterization of Natural Hybrids Formed between Five Related Indigenous Clade 6 Phytophthora Species

    Science.gov (United States)

    Burgess, Treena I.

    2015-01-01

    Most Phytophthora hybrids characterized to date have emerged from nurseries and managed landscapes, most likely generated as a consequence of biological invasions associated with the movement of living plants and germplasm for ornamental, horticultural and agricultural purposes. Presented here is evidence for natural hybridization among a group of five closely related indigenous clade 6 Phytophthora species isolated from waterways and riparian ecosystems in Western Australia. Molecular characterization of hybrids consisted of cloning and sequencing two nuclear genes (ITS and ASF), sequencing of two further nuclear loci (BT and HSP) and of two mitochondrial loci (COI and NADH). Additionally, phenotypic traits including morphology of sporangia and optima and maxima temperatures for growth were also determined. In most cases the nuclear genes were biparentally and in all cases the mtDNA were uniparentally inherited, indicating hybrid formation through sexual crosses. Some isolates bear the molecular signature of three parents suggesting additional hybrid events, although it cannot be determined from the data if these were sequential or simultaneous. These species and their hybrids co-exist in riparian ecosystems and waterways where their ability for rapid asexual proliferation would enable them to rapidly colonize green plant litter. The apparent ease of hybridization could eventually lead to the merging of species through introgression. However, at this point in time, species integrity has been maintained and a more likely scenario is that the hybrids are not stable evolutionary lineages, but rather transient hybrid clones. PMID:26248187

  11. The chloroplast genome of a symbiodinium sp. clade C3 isolate

    KAUST Repository

    Barbrook, Adrian C.

    2014-01-01

    Dinoflagellate algae of the genus Symbiodinium form important symbioses within corals and other benthic marine animals. Dinoflagellates possess an extremely reduced plastid genome relative to those examined in plants and other algae. In dinoflagellates the plastid genes are located on small plasmids, commonly referred to as \\'minicircles\\'. However, the chloroplast genomes of dinoflagellates have only been extensively characterised from a handful of species. There is also evidence of considerable variation in the chloroplast genome organisation across those species that have been examined. We therefore characterised the chloroplast genome from an environmental coral isolate, in this case containing a symbiont belonging to the Symbiodinium sp. clade C3. The gene content of the genome is well conserved with respect to previously characterised genomes. However, unlike previously characterised dinoflagellate chloroplast genomes we did not identify any \\'empty\\' minicircles. The sequences of this chloroplast genome show a high rate of evolution relative to other algal species. Particularly notable was a surprisingly high level of sequence divergence within the core polypeptides of photosystem I, the reasons for which are currently unknown. This chloroplast genome also possesses distinctive codon usage and GC content. These features suggest that chloroplast genomes in Symbiodinium are highly plastic. © 2013 Adrian C. Barbrook.

  12. The chloroplast genome of a symbiodinium sp. clade C3 isolate

    KAUST Repository

    Barbrook, Adrian C.; Voolstra, Christian R.; Howe, Christopher J.

    2014-01-01

    Dinoflagellate algae of the genus Symbiodinium form important symbioses within corals and other benthic marine animals. Dinoflagellates possess an extremely reduced plastid genome relative to those examined in plants and other algae. In dinoflagellates the plastid genes are located on small plasmids, commonly referred to as 'minicircles'. However, the chloroplast genomes of dinoflagellates have only been extensively characterised from a handful of species. There is also evidence of considerable variation in the chloroplast genome organisation across those species that have been examined. We therefore characterised the chloroplast genome from an environmental coral isolate, in this case containing a symbiont belonging to the Symbiodinium sp. clade C3. The gene content of the genome is well conserved with respect to previously characterised genomes. However, unlike previously characterised dinoflagellate chloroplast genomes we did not identify any 'empty' minicircles. The sequences of this chloroplast genome show a high rate of evolution relative to other algal species. Particularly notable was a surprisingly high level of sequence divergence within the core polypeptides of photosystem I, the reasons for which are currently unknown. This chloroplast genome also possesses distinctive codon usage and GC content. These features suggest that chloroplast genomes in Symbiodinium are highly plastic. © 2013 Adrian C. Barbrook.

  13. In situ morphometric survey elucidates the evolutionary systematics of the Eurasian Himantoglossum clade (Orchidaceae: Orchidinae

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    Richard M. Bateman

    2017-01-01

    Full Text Available Background and Aims The charismatic Himantoglossum s.l. clade of Eurasian orchids contains an unusually large proportion of taxa that are of controversial circumscriptions and considerable conservation concern. Whereas our previously published study addressed the molecular phylogenetics and phylogeography of every named taxon within the clade, here we use detailed morphometric data obtained from the same populations to compare genotypes with associated phenotypes, in order to better explore taxonomic circumscription and character evolution within the clade. Methods Between one and 12 plants found in 25 populations that encompassed the entire distribution of the Himantoglossum s.l. clade were measured in situ for 51 morphological characters. Results for 45 of those characters were subjected to detailed multivariate and univariate analyses. Key Results Multivariate analyses readily separate subgenus Barlia and subgenus Comperia from subgenus Himantoglossum, and also the early-divergent H. formosum from the less divergent remainder of subgenus Himantoglossum. The sequence of divergence of these four lineages is confidently resolved. Our experimental approach to morphometric character analysis demonstrates clearly that phenotypic evolution within Himantoglossum is unusually multi-dimensional. Conclusions Degrees of divergence between taxa shown by morphological analyses approximate those previously shown using molecular analyses. Himantoglossum s.l. is readily divisible into three subgenera. The three sections of subgenus Himantoglossum—hircinum, caprinum and formosum—are arrayed from west to east with only limited geographical overlap. At this taxonomic level, their juxtaposition combines with conflict between contrasting datasets to complicate attempts to distinguish between clinal variation and the discontinuities that by definition separate bona fide species. All taxa achieve allogamy via food deceit and have only weak pollinator specificity

  14. Exploring genetic variation in the tomato (Solanum section Lycopersicon) clade by whole-genome sequencing.

    Science.gov (United States)

    Aflitos, Saulo; Schijlen, Elio; de Jong, Hans; de Ridder, Dick; Smit, Sandra; Finkers, Richard; Wang, Jun; Zhang, Gengyun; Li, Ning; Mao, Likai; Bakker, Freek; Dirks, Rob; Breit, Timo; Gravendeel, Barbara; Huits, Henk; Struss, Darush; Swanson-Wagner, Ruth; van Leeuwen, Hans; van Ham, Roeland C H J; Fito, Laia; Guignier, Laëtitia; Sevilla, Myrna; Ellul, Philippe; Ganko, Eric; Kapur, Arvind; Reclus, Emannuel; de Geus, Bernard; van de Geest, Henri; Te Lintel Hekkert, Bas; van Haarst, Jan; Smits, Lars; Koops, Andries; Sanchez-Perez, Gabino; van Heusden, Adriaan W; Visser, Richard; Quan, Zhiwu; Min, Jiumeng; Liao, Li; Wang, Xiaoli; Wang, Guangbiao; Yue, Zhen; Yang, Xinhua; Xu, Na; Schranz, Eric; Smets, Erik; Vos, Rutger; Rauwerda, Johan; Ursem, Remco; Schuit, Cees; Kerns, Mike; van den Berg, Jan; Vriezen, Wim; Janssen, Antoine; Datema, Erwin; Jahrman, Torben; Moquet, Frederic; Bonnet, Julien; Peters, Sander

    2014-10-01

    We explored genetic variation by sequencing a selection of 84 tomato accessions and related wild species representative of the Lycopersicon, Arcanum, Eriopersicon and Neolycopersicon groups, which has yielded a huge amount of precious data on sequence diversity in the tomato clade. Three new reference genomes were reconstructed to support our comparative genome analyses. Comparative sequence alignment revealed group-, species- and accession-specific polymorphisms, explaining characteristic fruit traits and growth habits in the various cultivars. Using gene models from the annotated Heinz 1706 reference genome, we observed differences in the ratio between non-synonymous and synonymous SNPs (dN/dS) in fruit diversification and plant growth genes compared to a random set of genes, indicating positive selection and differences in selection pressure between crop accessions and wild species. In wild species, the number of single-nucleotide polymorphisms (SNPs) exceeds 10 million, i.e. 20-fold higher than found in most of the crop accessions, indicating dramatic genetic erosion of crop and heirloom tomatoes. In addition, the highest levels of heterozygosity were found for allogamous self-incompatible wild species, while facultative and autogamous self-compatible species display a lower heterozygosity level. Using whole-genome SNP information for maximum-likelihood analysis, we achieved complete tree resolution, whereas maximum-likelihood trees based on SNPs from ten fruit and growth genes show incomplete resolution for the crop accessions, partly due to the effect of heterozygous SNPs. Finally, results suggest that phylogenetic relationships are correlated with habitat, indicating the occurrence of geographical races within these groups, which is of practical importance for Solanum genome evolution studies. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  15. A unique species in Phytophthora clade 10, Phytophthora intercalaris sp. nov., recovered from stream and irrigation water in the eastern USA

    Science.gov (United States)

    Balci, Y.; Brazee, N. J.; Loyd, A. L.; Hong, C. X.

    2016-01-01

    A novel species of the genus Phytophthora was recovered during surveys of stream and nursery irrigation water in Maryland, Massachusetts, North Carolina, Virginia and West Virginia in the USA. The novel species is heterothallic, and all examined isolates were A1 mating type. It produced rare ornamented oogonia and amphigynous antheridia when paired with A2 mating type testers of Phytophthora cinnamomi and Phytophthora cryptogea. Sporangia of this novel species were non-papillate and non-caducous. Thin-walled intercalary chlamydospores were abundant in hemp seed agar and carrot agar, while they were produced only rarely in aged cultures grown in clarified V8 juice agar. Phylogenetic analyses based on sequences of the internal transcribed spacer region and the β-tubulin and mitochondrial cytochrome-c oxidase 1 (cox1) genes indicated that the novel species is phylogenetically close to Phytophthora gallica in Phytophthora clade 10. The novel species has morphological and molecular features that are distinct from those of other species in Phytophthora clade 10. It is formally described here as Phytophthora intercalaris sp. nov. Description of this unique clade-10 species is important for understanding the phylogeny and evolution of Phytophthora clade 10. PMID:26620125

  16. Phylogenomic analysis resolves the formerly intractable adaptive diversification of the endemic clade of east Asian Cyprinidae (Cypriniformes.

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    Wenjing Tao

    Full Text Available Despite their great diversity and biological importance, evolutionary relationships among the endemic clade of East Asian Cyprinidae remain ambiguous. Understanding the phylogenetic history of this group involves many challenges. For instance, ecomorphological convergence may confound morphology-based phylogenetic inferences, and previous molecular phylogenetic studies based on single genes have often yielded contradictory and poorly supported trees. We assembled a comprehensive data matrix of 100 nuclear gene segments (∼ 71132 base pairs for representative species of the endemic East Asian cyprinid fauna and recovered a robust phylogeny from this genome-wide signal supported by multiple analytical methods, including maximum parsimony, maximum likelihood and Bayesian inference. Relaxed molecular clock analyses indicated species radiations of this clade concentrated at approximately 1.9-7.6 MYA. We provide evidence that the bursts of diversification in this fauna are directly linked to major paleoenvironmental events associated with monsoon evolution occurring from late Miocene to Pliocene. Ancestral state reconstruction reveals convergent morphological characters are hypothesized to be independent products of similar selective pressures in ecosystems. Our study is the first comprehensive phylogenetic study of the enigmatic East-Asian cyprinids. The explicit molecular phylogeny provides a valuable framework for future research in genome evolution, adaptation and speciation of cyprinids.

  17. Greatly reduced phylogenetic structure in the cultivated potato clade of potatoes, Solanum section Petota

    Science.gov (United States)

    The species boundaries of wild and cultivated potatoes, Solanum section Petota, are controversial with most of the taxonomic problems in a clade containing cultivated potatoes. We here provide the first in-depth phylogenetic study of the cultivated potato clade to explore possible causes of these pr...

  18. A genetic polymorphism evolving in parallel in two cell compartments and in two clades

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    Watt Ward B

    2013-01-01

    Full Text Available Abstract Background The enzyme phosphoenolpyruvate carboxykinase, PEPCK, occurs in its guanosine-nucleotide-using form in animals and a few prokaryotes. We study its natural genetic variation in Colias (Lepidoptera, Pieridae. PEPCK offers a route, alternative to pyruvate kinase, for carbon skeletons to move between cytosolic glycolysis and mitochondrial Krebs cycle reactions. Results PEPCK is expressed in both cytosol and mitochondrion, but differently in diverse animal clades. In vertebrates and independently in Drosophila, compartment-specific paralogous genes occur. In a contrasting expression strategy, compartment-specific PEPCKs of Colias and of the silkmoth, Bombyx, differ only in their first, 5′, exons; these are alternatively spliced onto a common series of following exons. In two Colias species from distinct clades, PEPCK sequence is highly variable at nonsynonymous and synonymous sites, mainly in its common exons. Three major amino acid polymorphisms, Gly 335 ↔ Ser, Asp 503 ↔ Glu, and Ile 629 ↔ Val occur in both species, and in the first two cases are similar in frequency between species. Homology-based structural modelling shows that the variants can alter hydrogen bonding, salt bridging, or van der Waals interactions of amino acid side chains, locally or at one another′s sites which are distant in PEPCK′s structure, and thus may affect its enzyme function. We ask, using coalescent simulations, if these polymorphisms′ cross-species similarities are compatible with neutral evolution by genetic drift, but find the probability of this null hypothesis is 0.001 ≤ P ≤ 0.006 under differing scenarios. Conclusion Our results make the null hypothesis of neutrality of these PEPCK polymorphisms quite unlikely, but support an alternative hypothesis that they are maintained by natural selection in parallel in the two species. This alternative can now be justifiably tested further via studies of PEPCK genotypes′ effects

  19. Progress to extinction: increased specialisation causes the demise of animal clades.

    Science.gov (United States)

    Raia, P; Carotenuto, F; Mondanaro, A; Castiglione, S; Passaro, F; Saggese, F; Melchionna, M; Serio, C; Alessio, L; Silvestro, D; Fortelius, M

    2016-08-10

    Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are effective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time.

  20. Phylogenetic Signal of Threatening Processes among Hylids: The Need for Clade-Level Conservation Planning

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    Sarah J. Corey

    2010-01-01

    Full Text Available Rapid, global declines among amphibians are partly alarming because many occur for apparently unknown or enigmatic reasons. Moreover, the relationship between phylogeny and enigmatic declines in higher clades of the amphibian phylogeny appears at first to be an intractable problem. I present a working solution by assessing threatening processes potentially underlying enigmatic declines in the family, Hylidae. Applying comparative methods that account for various evolutionary scenarios, I find extreme concentrations of threatening processes, including pollution and habitat loss, in the clade Hylini, potentially influenced by traits under selection. The analysis highlights hotspots of declines under phylogenetic influence in the genera Isthmohyla, Plectrohyla and Ptychohyla, and geographically in Mexico and Guatemala. The conservation implications of concentrated phylogenetic influence across multiple threatening processes are twofold: Data Deficient species of threatened clades should be prioritized in future surveys and, perhaps, a greater vulnerability should be assigned to such clades for further consideration of clade-level conservation priorities.

  1. Progress to extinction: increased specialisation causes the demise of animal clades

    Science.gov (United States)

    Raia, P.; Carotenuto, F.; Mondanaro, A.; Castiglione, S.; Passaro, F.; Saggese, F.; Melchionna, M.; Serio, C.; Alessio, L.; Silvestro, D.; Fortelius, M.

    2016-08-01

    Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are effective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time.

  2. A novel thymidylate synthase from the Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP) clade with altered nucleotide and folate binding sites.

    Science.gov (United States)

    Lopez-Zavala, Alonso A; Guevara-Hernandez, Eduardo; Vazquez-Lujan, Luz H; Sanchez-Paz, Arturo; Garcia-Orozco, Karina D; Contreras-Vergara, Carmen A; Lopez-Leal, Gamaliel; Arvizu-Flores, Aldo A; Ochoa-Leyva, Adrian; Sotelo-Mundo, Rogerio R

    2018-01-01

    Thymidylate synthase (TS, E.C. 2.1.1.45) is a crucial enzyme for de novo deoxythymidine monophosphate (dTMP) biosynthesis. The gene for this enzyme is thyA , which encodes the folate-dependent TS that converts deoxyuridine monophosphate group (dUMP) into (dTMP) using the cofactor 5,10-methylenetetrahydrofolate (mTHF) as a carbon donor. We identified the thyA gene in the genome of the Vibrio parahaemolyticus strain FIM-S1708+ that is innocuous to humans but pathogenic to crustaceans. Surprisingly, we found changes in the residues that bind the substrate dUMP and mTHF, previously postulated as invariant among all TSs known (Finer-Moore, Santi & Stroud, 2003). Interestingly, those amino acid changes were also found in a clade of microorganisms that contains Vibrionales , Alteromonadales , Aeromonadales , and Pasteurellales (VAAP) from the Gammaproteobacteria class. In this work, we studied the biochemical properties of recombinant TS from V. parahemolyticus FIM-S1708+ (VpTS) to address the natural changes in the TS amino acid sequence of the VAAP clade. Interestingly, the K m for dUMP was 27.3 ± 4.3 µM, about one-fold larger compared to other TSs. The K m for mTHF was 96.3 ± 18 µM, about three- to five-fold larger compared to other species, suggesting also loss of affinity. Thus, the catalytic efficiency was between one or two orders of magnitude smaller for both substrates. We used trimethoprim, a common antibiotic that targets both TS and DHFR for inhibition studies. The IC 50 values obtained were high compared to other results in the literature. Nonetheless, this molecule could be a lead for the design antibiotics towards pathogens from the VAAP clade. Overall, the experimental results also suggest that in the VAAP clade the nucleotide salvage pathway is important and should be investigated, since the de novo dTMP synthesis appears to be compromised by a less efficient thymidylate synthase.

  3. A novel thymidylate synthase from the Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP clade with altered nucleotide and folate binding sites

    Directory of Open Access Journals (Sweden)

    Alonso A. Lopez-Zavala

    2018-06-01

    Full Text Available Thymidylate synthase (TS, E.C. 2.1.1.45 is a crucial enzyme for de novo deoxythymidine monophosphate (dTMP biosynthesis. The gene for this enzyme is thyA, which encodes the folate-dependent TS that converts deoxyuridine monophosphate group (dUMP into (dTMP using the cofactor 5,10-methylenetetrahydrofolate (mTHF as a carbon donor. We identified the thyA gene in the genome of the Vibrio parahaemolyticus strain FIM-S1708+ that is innocuous to humans but pathogenic to crustaceans. Surprisingly, we found changes in the residues that bind the substrate dUMP and mTHF, previously postulated as invariant among all TSs known (Finer-Moore, Santi & Stroud, 2003. Interestingly, those amino acid changes were also found in a clade of microorganisms that contains Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP from the Gammaproteobacteria class. In this work, we studied the biochemical properties of recombinant TS from V. parahemolyticus FIM-S1708+ (VpTS to address the natural changes in the TS amino acid sequence of the VAAP clade. Interestingly, the Km for dUMP was 27.3 ± 4.3 µM, about one-fold larger compared to other TSs. The Km for mTHF was 96.3 ± 18 µM, about three- to five-fold larger compared to other species, suggesting also loss of affinity. Thus, the catalytic efficiency was between one or two orders of magnitude smaller for both substrates. We used trimethoprim, a common antibiotic that targets both TS and DHFR for inhibition studies. The IC50 values obtained were high compared to other results in the literature. Nonetheless, this molecule could be a lead for the design antibiotics towards pathogens from the VAAP clade. Overall, the experimental results also suggest that in the VAAP clade the nucleotide salvage pathway is important and should be investigated, since the de novo dTMP synthesis appears to be compromised by a less efficient thymidylate synthase.

  4. Resurrecting a subgenus to genus: molecular phylogeny of Euphyllia and Fimbriaphyllia (order Scleractinia; family Euphyllidae; clade V

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    Katrina S. Luzon

    2017-12-01

    Full Text Available Background The corallum is crucial in building coral reefs and in diagnosing systematic relationships in the order Scleractinia. However, molecular phylogenetic analyses revealed a paraphyly in a majority of traditional families and genera among Scleractinia showing that other biological attributes of the coral, such as polyp morphology and reproductive traits, are underutilized. Among scleractinian genera, the Euphyllia, with nine nominal species in the Indo-Pacific region, is one of the groups that await phylogenetic resolution. Multiple genetic markers were used to construct the phylogeny of six Euphyllia species, namely E. ancora, E. divisa, E. glabrescens, E. paraancora, E. paradivisa, and E. yaeyamaensis. The phylogeny guided the inferences on the contributions of the colony structure, polyp morphology, and life history traits to the systematics of the largest genus in Euphyllidae (clade V and, by extension, to the rest of clade V. Results Analyses of cytochrome oxidase 1 (cox1, cytochrome b (cytb, and β-tubulin genes of 36 colonies representing Euphyllia and a confamilial species, Galaxea fascicularis, reveal two distinct groups in the Euphyllia that originated from different ancestors. Euphyllia glabrescens formed a separate group. Euphyllia ancora, E. divisa, E. paraancora, E. paradivisa, and E. yaeyamaensis clustered together and diverged from the same ancestor as G. fascicularis. The 3′-end of the cox1 gene of Euphyllia was able to distinguish morphospecies. Discussion Species of Euphyllia were traditionally classified into two subgenera, Euphyllia and Fimbriaphyllia, which represented a dichotomy on colony structure. The paraphyletic groups retained the original members of the subgenera providing a strong basis for recognizing Fimbriaphyllia as a genus. However, colony structure was found to be a convergent trait between Euphyllia and Fimbriaphyllia, while polyp shape and length, sexuality, and reproductive mode defined the

  5. Three New Soil-inhabiting Species of Trichoderma in the Stromaticum Clade with Test of Their Antagonism to Pathogens.

    Science.gov (United States)

    Chen, Kai; Zhuang, Wen-Ying

    2017-09-01

    Trichoderma is a dominant component of the soil mycoflora. During the field investigations of northern, central, and southwestern China, three new species in the Stromaticum clade were encountered from soil, and named as T. hebeiense, T. sichuanense, and T. verticillatum. Their phylogenetic positions were determined by analyses of the combined two genes: partial sequences of translation elongation factor 1-alpha and the second largest RNA polymerase subunit-encoding genes. Distinctions between the new species and their close relatives were discussed. Trichoderma hebeiense appeared as a separate terminal branch. The species is distinctive by its oblong conidia and aggregated pustules in culture. Trichoderma sichuanense features in concentric colony and produces numerous clean exudates on aerial mycelium in culture. Trichoderma verticillatum is characterized by its verticillium-like synanamorph and production of abundant chlamydospores. In vitro antagonism towards the new species was tested by dual culture technique.

  6. Spinning Gland Transcriptomics from Two Main Clades of Spiders (Order: Araneae) - Insights on Their Molecular, Anatomical and Behavioral Evolution

    Science.gov (United States)

    Prosdocimi, Francisco; Bittencourt, Daniela; da Silva, Felipe Rodrigues; Kirst, Matias; Motta, Paulo C.; Rech, Elibio L.

    2011-01-01

    Characterized by distinctive evolutionary adaptations, spiders provide a comprehensive system for evolutionary and developmental studies of anatomical organs, including silk and venom production. Here we performed cDNA sequencing using massively parallel sequencers (454 GS-FLX Titanium) to generate ∼80,000 reads from the spinning gland of Actinopus spp. (infraorder: Mygalomorphae) and Gasteracantha cancriformis (infraorder: Araneomorphae, Orbiculariae clade). Actinopus spp. retains primitive characteristics on web usage and presents a single undifferentiated spinning gland while the orbiculariae spiders have seven differentiated spinning glands and complex patterns of web usage. MIRA, Celera Assembler and CAP3 software were used to cluster NGS reads for each spider. CAP3 unigenes passed through a pipeline for automatic annotation, classification by biological function, and comparative transcriptomics. Genes related to spider silks were manually curated and analyzed. Although a single spidroin gene family was found in Actinopus spp., a vast repertoire of specialized spider silk proteins was encountered in orbiculariae. Astacin-like metalloproteases (meprin subfamily) were shown to be some of the most sampled unigenes and duplicated gene families in G. cancriformis since its evolutionary split from mygalomorphs. Our results confirm that the evolution of the molecular repertoire of silk proteins was accompanied by the (i) anatomical differentiation of spinning glands and (ii) behavioral complexification in the web usage. Finally, a phylogenetic tree was constructed to cluster most of the known spidroins in gene clades. This is the first large-scale, multi-organism transcriptome for spider spinning glands and a first step into a broad understanding of spider web systems biology and evolution. PMID:21738742

  7. Spinning gland transcriptomics from two main clades of spiders (order: Araneae--insights on their molecular, anatomical and behavioral evolution.

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    Francisco Prosdocimi

    Full Text Available Characterized by distinctive evolutionary adaptations, spiders provide a comprehensive system for evolutionary and developmental studies of anatomical organs, including silk and venom production. Here we performed cDNA sequencing using massively parallel sequencers (454 GS-FLX Titanium to generate ∼80,000 reads from the spinning gland of Actinopus spp. (infraorder: Mygalomorphae and Gasteracantha cancriformis (infraorder: Araneomorphae, Orbiculariae clade. Actinopus spp. retains primitive characteristics on web usage and presents a single undifferentiated spinning gland while the orbiculariae spiders have seven differentiated spinning glands and complex patterns of web usage. MIRA, Celera Assembler and CAP3 software were used to cluster NGS reads for each spider. CAP3 unigenes passed through a pipeline for automatic annotation, classification by biological function, and comparative transcriptomics. Genes related to spider silks were manually curated and analyzed. Although a single spidroin gene family was found in Actinopus spp., a vast repertoire of specialized spider silk proteins was encountered in orbiculariae. Astacin-like metalloproteases (meprin subfamily were shown to be some of the most sampled unigenes and duplicated gene families in G. cancriformis since its evolutionary split from mygalomorphs. Our results confirm that the evolution of the molecular repertoire of silk proteins was accompanied by the (i anatomical differentiation of spinning glands and (ii behavioral complexification in the web usage. Finally, a phylogenetic tree was constructed to cluster most of the known spidroins in gene clades. This is the first large-scale, multi-organism transcriptome for spider spinning glands and a first step into a broad understanding of spider web systems biology and evolution.

  8. Comparing the Effects of Symbiotic Algae (Symbiodinium) Clades C1 and D on Early Growth Stages of Acropora tenuis

    Science.gov (United States)

    Yuyama, Ikuko; Higuchi, Tomihiko

    2014-01-01

    Reef-building corals switch endosymbiotic algae of the genus Symbiodinium during their early growth stages and during bleaching events. Clade C Symbiodinium algae are dominant in corals, although other clades — including A and D — have also been commonly detected in juvenile Acroporid corals. Previous studies have been reported that only molecular data of Symbiodinium clade were identified within field corals. In this study, we inoculated aposymbiotic juvenile polyps with cultures of clades C1 and D Symbiodinium algae, and investigated the different effect of these two clades of Symbiodinium on juvenile polyps. Our results showed that clade C1 algae did not grow, while clade D algae grew rapidly during the first 2 months after inoculation. Polyps associated with clade C1 algae exhibited bright green fluorescence across the body and tentacles after inoculation. The growth rate of polyp skeletons was lower in polyps associated with clade C1 algae than those associated with clade D algae. On the other hand, antioxidant activity (catalase) of corals was not significantly different between corals with clade C1 and clade D algae. Our results suggested that clade D Symbiodinium algae easily form symbiotic relationships with corals and that these algae could contribute to coral growth in early symbiosis stages. PMID:24914677

  9. Gene

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes,...

  10. Phylogenetics of Cucumis (Cucurbitaceae: Cucumber (C. sativus belongs in an Asian/Australian clade far from melon (C. melo

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    Schaefer Hanno

    2007-04-01

    Full Text Available Abstract Background Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F, adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Results Analyses of combined chloroplast sequences (4,375 aligned nucleotides for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Conclusion Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian

  11. Phylogenomics reveals rapid, simultaneous diversification of three major clades of Gondwanan frogs at the Cretaceous–Paleogene boundary

    Science.gov (United States)

    Feng, Yan-Jie; Liang, Dan; Hillis, David M.; Cannatella, David C.; Zhang, Peng

    2017-01-01

    Frogs (Anura) are one of the most diverse groups of vertebrates and comprise nearly 90% of living amphibian species. Their worldwide distribution and diverse biology make them well-suited for assessing fundamental questions in evolution, ecology, and conservation. However, despite their scientific importance, the evolutionary history and tempo of frog diversification remain poorly understood. By using a molecular dataset of unprecedented size, including 88-kb characters from 95 nuclear genes of 156 frog species, in conjunction with 20 fossil-based calibrations, our analyses result in the most strongly supported phylogeny of all major frog lineages and provide a timescale of frog evolution that suggests much younger divergence times than suggested by earlier studies. Unexpectedly, our divergence-time analyses show that three species-rich clades (Hyloidea, Microhylidae, and Natatanura), which together comprise ∼88% of extant anuran species, simultaneously underwent rapid diversification at the Cretaceous–Paleogene (K–Pg) boundary (KPB). Moreover, anuran families and subfamilies containing arboreal species originated near or after the KPB. These results suggest that the K–Pg mass extinction may have triggered explosive radiations of frogs by creating new ecological opportunities. This phylogeny also reveals relationships such as Microhylidae being sister to all other ranoid frogs and African continental lineages of Natatanura forming a clade that is sister to a clade of Eurasian, Indian, Melanesian, and Malagasy lineages. Biogeographical analyses suggest that the ancestral area of modern frogs was Africa, and their current distribution is largely associated with the breakup of Pangaea and subsequent Gondwanan fragmentation. PMID:28673970

  12. Bad Clade Deletion Supertrees: A Fast and Accurate Supertree Algorithm.

    Science.gov (United States)

    Fleischauer, Markus; Böcker, Sebastian

    2017-09-01

    Supertree methods merge a set of overlapping phylogenetic trees into a supertree containing all taxa of the input trees. The challenge in supertree reconstruction is the way of dealing with conflicting information in the input trees. Many different algorithms for different objective functions have been suggested to resolve these conflicts. In particular, there exist methods based on encoding the source trees in a matrix, where the supertree is constructed applying a local search heuristic to optimize the respective objective function. We present a novel heuristic supertree algorithm called Bad Clade Deletion (BCD) supertrees. It uses minimum cuts to delete a locally minimal number of columns from such a matrix representation so that it is compatible. This is the complement problem to Matrix Representation with Compatibility (Maximum Split Fit). Our algorithm has guaranteed polynomial worst-case running time and performs swiftly in practice. Different from local search heuristics, it guarantees to return the directed perfect phylogeny for the input matrix, corresponding to the parent tree of the input trees, if one exists. Comparing supertrees to model trees for simulated data, BCD shows a better accuracy (F1 score) than the state-of-the-art algorithms SuperFine (up to 3%) and Matrix Representation with Parsimony (up to 7%); at the same time, BCD is up to 7 times faster than SuperFine, and up to 600 times faster than Matrix Representation with Parsimony. Finally, using the BCD supertree as a starting tree for a combined Maximum Likelihood analysis using RAxML, we reach significantly improved accuracy (1% higher F1 score) and running time (1.7-fold speedup). © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  13. Sigma viruses from three species of Drosophila form a major new clade in the rhabdovirus phylogeny

    Science.gov (United States)

    Longdon, Ben; Obbard, Darren J.; Jiggins, Francis M.

    2010-01-01

    The sigma virus (DMelSV), which is a natural pathogen of Drosophila melanogaster, is the only Drosophila-specific rhabdovirus that has been described. We have discovered two new rhabdoviruses, D. obscura and D. affinis, which we have named DObsSV and DAffSV, respectively. We sequenced the complete genomes of DObsSV and DMelSV, and the L gene from DAffSV. Combining these data with sequences from a wide range of other rhabdoviruses, we found that the three sigma viruses form a distinct clade which is a sister group to the Dimarhabdovirus supergroup, and the high levels of divergence between these viruses suggest that they deserve to be recognized as a new genus. Furthermore, our analysis produced the most robustly supported phylogeny of the Rhabdoviridae to date, allowing us to reconstruct the major transitions that have occurred during the evolution of the family. Our data suggest that the bias towards research into plants and vertebrates means that much of the diversity of rhabdoviruses has been missed, and rhabdoviruses may be common pathogens of insects. PMID:19812076

  14. An unexpected clade of South American ground beetles (Coleoptera, Carabidae, Bembidion).

    Science.gov (United States)

    Maddison, David R

    2014-01-01

    Phylogenetic relationships of the Antiperyphanes Complex of the genus Bembidion are inferred using DNA sequences from seven genes (two nuclear ribosomal, four nuclear protein coding, and one mitochondrial protein coding). Redefined subgenera within the complex are each well-supported as monophyletic. Most striking was the discovery that a small set of morphologically and ecologically heterogeneous species formed a clade, here called subgenus Nothonepha. This unexpected result was corroborated by the discovery of deep pits in the lateral body wall (in the mesepisternum) of all Nothonepha, a trait unique within Bembidion. These pits are filled with a waxy substance in ethanol-preserved specimens. In one newly discovered species (Bembidion tetrapholeon sp. n., described here), these pits are so deep that their projections into the body cavity from the two sides touch each other internally. These structures in Bembidion (Nothonepha) are compared to very similar mesepisternal pits which have convergently evolved in two other groups of carabid beetles. The function of these thoracic pits is unknown. Most members of subgenus Nothonepha have in addition similar but smaller pits in the abdomen. A revised classification is proposed for the Antiperyphanes Complex.

  15. An unexpected clade of South American ground beetles (Coleoptera, Carabidae, Bembidion

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    David Maddison

    2014-06-01

    Full Text Available Phylogenetic relationships of the Antiperyphanes Complex of the genus Bembidion are inferred using DNA sequences from seven genes (two nuclear ribosomal, four nuclear protein coding, and one mitochondrial protein coding. Redefined subgenera within the complex are each well-supported as monophyletic. Most striking was the discovery that a small set of morphologically and ecologically heterogeneous species formed a clade, here called subgenus Nothonepha. This unexpected result was corroborated by the discovery of deep pits in the lateral body wall (in the mesepisternum of all Nothonepha, a trait unique within Bembidion. These pits are filled with a waxy substance in ethanol-preserved specimens. In one newly discovered species (Bembidion tetrapholeon sp. n., described here, these pits are so deep that their projections into the body cavity from the two sides touch each other internally. These structures in Bembidion (Nothonepha are compared to very similar mesepisternal pits which have convergently evolved in two other groups of carabid beetles. The function of these thoracic pits is unknown. Most members of subgenus Nothonepha have in addition similar but smaller pits in the abdomen. A revised classification is proposed for the Antiperyphanes Complex.

  16. Diversification of the Genus Anopheles and a Neotropical Clade from the Late Cretaceous.

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    Lucas A Freitas

    Full Text Available The Anopheles genus is a member of the Culicidae family and consists of approximately 460 recognized species. The genus is composed of 7 subgenera with diverse geographical distributions. Despite its huge medical importance, a consensus has not been reached on the phylogenetic relationships among Anopheles subgenera. We assembled a comprehensive dataset comprising the COI, COII and 5.8S rRNA genes and used maximum likelihood and Bayesian inference to estimate the phylogeny and divergence times of six out of the seven Anopheles subgenera. Our analysis reveals a monophyletic group composed of the three exclusively Neotropical subgenera, Stethomyia, Kerteszia and Nyssorhynchus, which began to diversify in the Late Cretaceous, at approximately 90 Ma. The inferred age of the last common ancestor of the Anopheles genus was ca. 110 Ma. The monophyly of all Anopheles subgenera was supported, although we failed to recover a significant level of statistical support for the monophyly of the Anopheles genus. The ages of the last common ancestors of the Neotropical clade and the Anopheles and Cellia subgenera were inferred to be at the Late Cretaceous (ca. 90 Ma. Our analysis failed to statistically support the monophyly of the Anopheles genus because of an unresolved polytomy between Bironella and A. squamifemur.

  17. Phylogeny, evolutionary trends and classification of the Spathelia-Ptaeroxylon clade: morphological and molecular insights.

    Science.gov (United States)

    Appelhans, M S; Smets, E; Razafimandimbison, S G; Haevermans, T; van Marle, E J; Couloux, A; Rabarison, H; Randrianarivelojosia, M; Kessler, P J A

    2011-06-01

    The Spathelia-Ptaeroxylon clade is a group of morphologically diverse plants that have been classified together as a result of molecular phylogenetic studies. The clade is currently included in Rutaceae and recognized at a subfamilial level (Spathelioideae) despite the fact that most of its genera have traditionally been associated with other families and that there are no obvious morphological synapomorphies for the clade. The aim of the present study is to construct phylogenetic trees for the Spathelia-Ptaeroxylon clade and to investigate anatomical characters in order to decide whether it should be kept in Rutaceae or recognized at the familial level. Anatomical characters were plotted on a cladogram to help explain character evolution within the group. Moreover, phylogenetic relationships and generic limits within the clade are also addressed. A species-level phylogenetic analysis of the Spathelia-Ptaeroxylon clade based on five plastid DNA regions (rbcL, atpB, trnL-trnF, rps16 and psbA-trnH) was conducted using Bayesian, maximum parsimony and maximum likelihood methods. Leaf and seed anatomical characters of all genera were (re)investigated by light and scanning electron microscopy. With the exception of Spathelia, all genera of the Spathelila-Ptaeroxylon clade are monophyletic. The typical leaf and seed anatomical characters of Rutaceae were found. Further, the presence of oil cells in the leaves provides a possible synapomorphy for the clade. The Spathelia-Ptaeroxylon clade is well placed in Rutaceae and it is reasonable to unite the genera into one subfamily (Spathelioideae). We propose a new tribal classification of Spathelioideae. A narrow circumscription of Spathelia is established to make the genus monophyletic, and Sohnreyia is resurrected to accommodate the South American species of Spathelia. The most recent common ancestor of Spathelioideae probably had leaves with secretory cavities and oil cells, haplostemonous flowers with appendaged staminal

  18. Phylogeny, evolutionary trends and classification of the Spathelia–Ptaeroxylon clade: morphological and molecular insights

    Science.gov (United States)

    Appelhans, M. S.; Smets, E.; Razafimandimbison, S. G.; Haevermans, T.; van Marle, E. J.; Couloux, A.; Rabarison, H.; Randrianarivelojosia, M.; Keßler, P. J. A.

    2011-01-01

    Background and Aims The Spathelia–Ptaeroxylon clade is a group of morphologically diverse plants that have been classified together as a result of molecular phylogenetic studies. The clade is currently included in Rutaceae and recognized at a subfamilial level (Spathelioideae) despite the fact that most of its genera have traditionally been associated with other families and that there are no obvious morphological synapomorphies for the clade. The aim of the present study is to construct phylogenetic trees for the Spathelia–Ptaeroxylon clade and to investigate anatomical characters in order to decide whether it should be kept in Rutaceae or recognized at the familial level. Anatomical characters were plotted on a cladogram to help explain character evolution within the group. Moreover, phylogenetic relationships and generic limits within the clade are also addressed. Methods A species-level phylogenetic analysis of the Spathelia–Ptaeroxylon clade based on five plastid DNA regions (rbcL, atpB, trnL–trnF, rps16 and psbA–trnH) was conducted using Bayesian, maximum parsimony and maximum likelihood methods. Leaf and seed anatomical characters of all genera were (re)investigated by light and scanning electron microscopy. Key Results With the exception of Spathelia, all genera of the Spathelila–Ptaeroxylon clade are monophyletic. The typical leaf and seed anatomical characters of Rutaceae were found. Further, the presence of oil cells in the leaves provides a possible synapomorphy for the clade. Conclusions The Spathelia–Ptaeroxylon clade is well placed in Rutaceae and it is reasonable to unite the genera into one subfamily (Spathelioideae). We propose a new tribal classification of Spathelioideae. A narrow circumscription of Spathelia is established to make the genus monophyletic, and Sohnreyia is resurrected to accommodate the South American species of Spathelia. The most recent common ancestor of Spathelioideae probably had leaves with secretory cavities

  19. A clade in the QUASIMODO2 family evolved with vascular plants and supports a role for cell wall composition in adaptation to environmental changes.

    Science.gov (United States)

    Fuentes, Sara; Pires, Nuno; Østergaard, Lars

    2010-08-01

    The evolution of plant vascular tissue is tightly linked to the evolution of specialised cell walls. Mutations in the QUASIMODO2 (QUA2) gene from Arabidopsis thaliana were previously shown to result in cell adhesion defects due to reduced levels of the cell wall component homogalacturonic acid. In this study, we provide additional information about the role of QUA2 and its closest paralogues, QUASIMODO2 LIKE1 (QUL1) and QUL2. Within the extensive QUA2 family, our phylogenetic analysis shows that these three genes form a clade that evolved with vascular plants. Consistent with a possible role of this clade in vasculature development, QUA2 is highly expressed in the vascular tissue of embryos and inflorescence stems and overexpression of QUA2 resulted in temperature-sensitive xylem collapse. Moreover, in-depth characterisation of qua2 qul1 qul2 triple mutant and 35S::QUA2 overexpression plants revealed contrasting temperature-dependent stem development with dramatic effects on stem width. Taken together, our results suggest that the QUA2-specific clade contributed to the evolution of vasculature and illustrate the important role that modification of cell wall composition plays in the adaptation to changing environmental conditions, including changes in temperature.

  20. A high-temperature tolerant species in clade 9 of the genus Phytophthora: P. hydrogena sp. nov.

    Science.gov (United States)

    Yang, Xiao; Gallegly, Mannon E; Hong, Chuanxue

    2014-01-01

    A previously unknown Phytophthora species was isolated from irrigation water in Virginia, USA. This novel species produces abundant noncaducous and nonpapillate sporangia in soil water extract solution. It sometimes produces chlamydospores and hyphal swellings in aged cultures and in Petri's solution. This species has optimum vegetative growth at 30 C and grows well at 35 C. The lowest and highest temperatures for growth are 5 and 40 C. All isolates examined in this study are compatibility type A1 and produce mostly plerotic oospores when paired with an A2 mating-type tester of P. cinnamomi. Sequence analyses of the rDNA internal transcribed spacer (ITS) regions and the mitochondrially encoded cytochrome c oxidase 1 (cox 1) gene placed this species in clade 9 of the genus Phytophthora. These characteristics support the description of this taxon as a new species for which we propose the name P. hydrogena sp. nov. Further phylogenetic and physiological investigations of clade 9 species revealed a high-temperature tolerant cluster including P. hydrogena, P. aquimorbida, P. hydropathica, P. irrigata, P. chrysanthemi, P. insolita, P. polonica and P. parsiana. These species all grow well at 35 C. The monophyly of the species in this heat-tolerant cluster except P. insolita and P. polonica is highly supported by the maximum-likelihood analyses of the ITS and cox 1 sequences.

  1. Transmission of a heterologous clade C Symbiodinium in a model anemone infection system via asexual reproduction

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    Wan-Nan U. Chen

    2016-08-01

    Full Text Available Anemones of genus Exaiptasia are used as model organisms for the study of cnidarian-dinoflagellate (genus Symbiodinium endosymbiosis. However, while most reef-building corals harbor Symbiodinium of clade C, Exaiptasia spp. anemones mainly harbor clade B Symbiodinium (ITS2 type B1 populations. In this study, we reveal for the first time that bleached Exaiptasia pallida anemones can establish a symbiotic relationship with a clade C Symbiodinium (ITS2 type C1. We further found that anemones can transmit the exogenously supplied clade C Symbiodinium cells to their offspring by asexual reproduction (pedal laceration. In order to corroborate the establishment of stable symbiosis, we used microscopic techniques and genetic analyses to examine several generations of anemones, and the results of these endeavors confirmed the sustainability of the system. These findings provide a framework for understanding the differences in infection dynamics between homologous and heterologous dinoflagellate types using a model anemone infection system.

  2. Complete genome sequence of Campylobacter jejuni strain 12567 a livestock-associated clade representative

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    We report the complete genome sequence of the Campylobacter jejuni strain 12567, a member of a C. jejuni livestock-associated clade that expresses glycoconjugates linked to improved gastrointestinal tract persistence....

  3. Novel sequence types of extended-spectrum and acquired AmpC beta-lactamase producing Escherichia coli and Escherichia clade V isolated from wild mammals.

    Science.gov (United States)

    Alonso, Carla Andrea; Alcalá, Leticia; Simón, Carmen; Torres, Carmen

    2017-08-01

    The closer contact with wildlife due to the growing human population and the destruction of natural habitats emphasizes the need of gaining insight into the role of animals as source of antimicrobial resistance. Here, we aim at characterizing the antimicrobial resistance genes and phylogenetic distribution of commensal Escherichia coli from 62 wild mammals. Isolates exhibiting resistance to ≥1 antibiotic were detected in 25.8% of the animals and 6.4% carried an extended-spectrum beta-lactamase (ESBL)/AmpC-producing E. coli. Genetic mechanisms involved in third-generation cephalosporin resistance were as follows: (i) hyperproduction of chromosomal AmpC (hedgehog), (ii) production of acquired CMY-2 β-lactamase (hedgehog), (iii) production of SHV-12 and CTX-M-14 ESBLs (n = 2, mink and roe-deer). ESBL genes were transferable by conjugation, and blaCMY-2 was mobilized by a 95kb IncI1 plasmid. The distribution of the phylogenetic groups in the E. coli collection studied was B1 (44.6%), B2 (24.6%), E (15.4%), A (4.6%) and F (3.1%). Five isolates (7.7%) were cryptic Escherichia clades (clade IV, 4 mice; clade V, 1 mink). ESBL/AmpC-E. coli isolates showed different sequence types (STs): ST1128/B1, ST4564/B1 (new), ST4996/B1 (new) and a non-registered ST. This study contributes to better understand the E. coli population and antimicrobial resistance flow in wildlife and reports new AmpC-E. coli STs and a first described ESBL-producing Escherichia clade V isolate. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Are Clade Specific HIV Vaccines a Necessity? An Analysis Based on Mathematical Models

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    Dobromir Dimitrov

    2015-12-01

    Full Text Available As HIV-1 envelope immune responses are critical to vaccine related protection, most candidate HIV vaccines entering efficacy trials are based upon a clade specific design. This need for clade specific vaccine prototypes markedly reduces the implementation of potentially effective HIV vaccines. We utilized a mathematical model to determine the effectiveness of immediate roll-out of a non-clade matched vaccine with reduced efficacy compared to constructing clade specific vaccines, which would take considerable time to manufacture and test in safety and efficacy trials. We simulated the HIV epidemic in San Francisco (SF and South Africa (SA and projected effectiveness of three vaccination strategies: i immediate intervention with a 20–40% vaccine efficacy (VE non-matched vaccine, ii delayed intervention by developing a 50% VE clade-specific vaccine, and iii immediate intervention with a non-matched vaccine replaced by a clade-specific vaccine when developed. Immediate vaccination with a non-clade matched vaccine, even with reduced efficacy, would prevent thousands of new infections in SF and millions in SA over 30 years. Vaccination with 50% VE delayed for five years needs six and 12 years in SA to break-even with immediate 20 and 30% VE vaccination, respectively, while not able to surpass the impact of immediate 40% VE vaccination over 30 years. Replacing a 30% VE with a 50% VE vaccine after 5 years reduces the HIV acquisition by 5% compared to delayed vaccination. The immediate use of an HIV vaccine with reduced VE in high risk communities appears desirable over a short time line but higher VE should be the pursued to achieve strong long-term impact. Our analysis illustrates the importance of developing surrogate markers (correlates of protection to allow bridging types of immunogenicity studies to support more rapid assessment of clade specific vaccines.

  5. Integrative Taxonomy of Amazon Reefs' Arenosclera spp.: A New Clade in the Haplosclerida (Demospongiae

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    Camille V. Leal

    2017-10-01

    Full Text Available Two new Arenosclera are described here on the basis of materials obtained from Amazon reefs in 2014, A. amazonensis sp. nov. and A. klausi sp. nov. Both are clearly distinct from all other Arenosclera by their erect, solid funnel to lamellate habit, larger oxeas, and ectosomal architecture bearing occasional multispicular tracts. An integrative approach to find the best classification for both new species failed to group them and A. heroni, the genus' type species. Nearly complete 28S rRNA sequences obtained from these species' metagenomes suggested instead a better placement for the new species and A. brasiliensis in clade C (sensu Redmond et al., 2013, while A. heroni fits best in clade A. We propose to name three clades according to the rules of the PhyloCode: Arenospiculap, Dactyclonap, and Dactyspiculap, respectively for the clade originating with the most recent common ancestor of the three Brazilian Arenosclera spp.; the most inclusive clade containing Dactylia varia (Gray, 1843 and Haliclona curacaoensis (van Soest, 1980; and the least inclusive clade containing Arenospiculap and Dactyclonap. A Karlin dinucleotide dissimilarity analysis of metagenomes carried out on cryopreserved samples recognized A. amazonensis sp. nov. as the most dissimilar species, thus suggesting a more particular microbiota is present in this Amazon species, an open avenue for extended applied study of this holobiont.

  6. Influenza A H5N1 clade 2.3.4 virus with a different antiviral susceptibility profile replaced clade 1 virus in humans in northern Vietnam

    NARCIS (Netherlands)

    Le, Mai T. Q.; Wertheim, Heiman F. L.; Nguyen, Hien D.; Taylor, Walter; Hoang, Phuong V. M.; Vuong, Cuong D.; Nguyen, Hang L. K.; Nguyen, Ha H.; Nguyen, Thai Q.; Nguyen, Trung V.; van, Trang D.; Ngoc, Bich T.; Bui, Thinh N.; Nguyen, Binh G.; Nguyen, Liem T.; Luong, San T.; Phan, Phuc H.; Pham, Hung V.; Nguyen, Tung; Fox, Annette; Nguyen, Cam V.; Do, Ha Q.; Crusat, Martin; Farrar, Jeremy; Nguyen, Hien T.; de Jong, Menno D.; Horby, Peter

    2008-01-01

    BACKGROUND: Prior to 2007, highly pathogenic avian influenza (HPAI) H5N1 viruses isolated from poultry and humans in Vietnam were consistently reported to be clade 1 viruses, susceptible to oseltamivir but resistant to amantadine. Here we describe the re-emergence of human HPAI H5N1 virus infections

  7. A novel extracellular gut symbiont in the marine worm Priapulus caudatus (Priapulida reveals an alphaproteobacterial symbiont clade of the Ecdysozoa

    Directory of Open Access Journals (Sweden)

    Paul eKroer

    2016-04-01

    Full Text Available Priapulus caudatus (phylum Priapulida is a benthic marine predatory worm with a cosmopolitan distribution. In its digestive tract we detected symbiotic bacteria that were consistently present in specimens collected over eight years from three sites at the Swedish west coast. Based on their 16S rRNA gene sequence, these symbionts comprise a novel genus of the order Rickettsiales (Alphaproteobacteria. Electron microscopy and fluorescence in situ hybridization (FISH identified them as extracellular, elongate bacteria closely associated with the microvilli, for which we propose the name ‘Candidatus Tenuibacter priapulorum’. Within Rickettsiales, they form a phylogenetically well-defined, family-level clade with uncultured symbionts of marine, terrestrial, and freshwater arthropods. Cand. Tenuibacter priapulorum expands the host range of this candidate family from Arthropoda to the entire Ecdysozoa, which may indicate an evolutionary adaptation of this bacterial group to the microvilli-lined guts of the Ecdysozoa.

  8. A Novel Extracellular Gut Symbiont in the Marine Worm Priapulus caudatus (Priapulida) Reveals an Alphaproteobacterial Symbiont Clade of the Ecdysozoa.

    Science.gov (United States)

    Kroer, Paul; Kjeldsen, Kasper U; Nyengaard, Jens R; Schramm, Andreas; Funch, Peter

    2016-01-01

    Priapulus caudatus (phylum Priapulida) is a benthic marine predatory worm with a cosmopolitan distribution. In its digestive tract we detected symbiotic bacteria that were consistently present in specimens collected over 8 years from three sites at the Swedish west coast. Based on their 16S rRNA gene sequence, these symbionts comprise a novel genus of the order Rickettsiales (Alphaproteobacteria). Electron microscopy and fluorescence in situ hybridization (FISH) identified them as extracellular, elongate bacteria closely associated with the microvilli, for which we propose the name "Candidatus Tenuibacter priapulorum". Within Rickettsiales, they form a phylogenetically well-defined, family-level clade with uncultured symbionts of marine, terrestrial, and freshwater arthropods. Cand. Tenuibacter priapulorum expands the host range of this candidate family from Arthropoda to the entire Ecdysozoa, which may indicate an evolutionary adaptation of this bacterial group to the microvilli-lined guts of the Ecdysozoa.

  9. Genetic Structure and Antimicrobial Resistance of Escherichia coli and Cryptic Clades in Birds with Diverse Human Associations.

    Science.gov (United States)

    Blyton, Michaela D J; Pi, Hongfei; Vangchhia, Belinda; Abraham, Sam; Trott, Darren J; Johnson, James R; Gordon, David M

    2015-08-01

    The manner and extent to which birds associate with humans may influence the genetic attributes and antimicrobial resistance of their commensal Escherichia communities through strain transmission and altered selection pressures. In this study, we determined whether the distribution of the different Escherichia coli phylogenetic groups and cryptic clades, the occurrence of 49 virulence associated genes, and/or the prevalence of resistance to 12 antimicrobials differed between four groups of birds from Australia with contrasting types of human association. We found that birds sampled in suburban and wilderness areas had similar Escherichia communities. The Escherichia communities of backyard domestic poultry were phylogenetically distinct from the Escherichia communities sourced from all other birds, with a large proportion (46%) of poultry strains belonging to phylogenetic group A and a significant minority (17%) belonging to the cryptic clades. Wild birds sampled from veterinary and wildlife rehabilitation centers (in-care birds) carried Escherichia isolates that possessed particular virulence-associated genes more often than Escherichia isolates from birds sampled in suburban and wilderness areas. The Escherichia isolates from both the backyard poultry and in-care birds were more likely to be multidrug resistant than the Escherichia isolates from wild birds. We also detected a multidrug-resistant E. coli strain circulating in a wildlife rehabilitation center, reinforcing the importance of adequate hygiene practices when handling and caring for wildlife. We suggest that the relatively high frequency of antimicrobial resistance in the in-care birds and backyard poultry is due primarily to the use of antimicrobials in these animals, and we recommend that the treatment protocols used for these birds be reviewed. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. Identification of the dominant sulfate-reducing bacterial partner of anaerobic methanotrophs of the ANME-2 clade.

    Science.gov (United States)

    Schreiber, Lars; Holler, Thomas; Knittel, Katrin; Meyerdierks, Anke; Amann, Rudolf

    2010-08-01

    The anaerobic oxidation of methane (AOM) with sulfate as terminal electron acceptor is mediated by consortia of methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB). Whereas three clades of ANME have been repeatedly studied with respect to phylogeny, key genes and genomic capabilities, little is known about their sulfate-reducing partner. In order to identify the partner of anaerobic methanotrophs of the ANME-2 clade, bacterial 16S rRNA gene libraries were constructed from cultures highly enriched for ANME-2a and ANME-2c in consortia with Deltaproteobacteria of the Desulfosarcina/Desulfococcus group (DSS). Phylogenetic analysis of those and publicly available sequences from AOM sites supported the hypothesis by Knittel and colleagues that the DSS partner belongs to the diverse SEEP-SRB1 cluster. Six subclusters of SEEP-SRB1, SEEP-SRB1a to SEEP-SRB1f, were proposed and specific oligonucleotide probes were designed. Using fluorescence in situ hybridization on samples from six different AOM sites, SEEP-SRB1a was identified as sulfate-reducing partner in up to 95% of total ANME-2 consortia. SEEP-SRB1a cells exhibited a rod-shaped, vibrioid, or coccoid morphology and were found to be associated with subgroups ANME-2a and ANME-2c. Moreover, SEEP-SRB1a was also detected in 8% to 23% of ANME-3 consortia in Haakon Mosby Mud Volcano sediments, previously described to be predominantly associated with SRB of the Desulfobulbus group. SEEP-SRB1a contributed to only 0.3% to 0.7% of all single cells in almost all samples indicating that these bacteria are highly adapted to a symbiotic relationship with ANME-2. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

  11. Evaluating ortholog prediction algorithms in a yeast model clade.

    Directory of Open Access Journals (Sweden)

    Leonidas Salichos

    Full Text Available BACKGROUND: Accurate identification of orthologs is crucial for evolutionary studies and for functional annotation. Several algorithms have been developed for ortholog delineation, but so far, manually curated genome-scale biological databases of orthologous genes for algorithm evaluation have been lacking. We evaluated four popular ortholog prediction algorithms (MultiParanoid; and OrthoMCL; RBH: Reciprocal Best Hit; RSD: Reciprocal Smallest Distance; the last two extended into clustering algorithms cRBH and cRSD, respectively, so that they can predict orthologs across multiple taxa against a set of 2,723 groups of high-quality curated orthologs from 6 Saccharomycete yeasts in the Yeast Gene Order Browser. RESULTS: Examination of sensitivity [TP/(TP+FN], specificity [TN/(TN+FP], and accuracy [(TP+TN/(TP+TN+FP+FN] across a broad parameter range showed that cRBH was the most accurate and specific algorithm, whereas OrthoMCL was the most sensitive. Evaluation of the algorithms across a varying number of species showed that cRBH had the highest accuracy and lowest false discovery rate [FP/(FP+TP], followed by cRSD. Of the six species in our set, three descended from an ancestor that underwent whole genome duplication. Subsequent differential duplicate loss events in the three descendants resulted in distinct classes of gene loss patterns, including cases where the genes retained in the three descendants are paralogs, constituting 'traps' for ortholog prediction algorithms. We found that the false discovery rate of all algorithms dramatically increased in these traps. CONCLUSIONS: These results suggest that simple algorithms, like cRBH, may be better ortholog predictors than more complex ones (e.g., OrthoMCL and MultiParanoid for evolutionary and functional genomics studies where the objective is the accurate inference of single-copy orthologs (e.g., molecular phylogenetics, but that all algorithms fail to accurately predict orthologs when paralogy

  12. Genomic characterization of two novel SAR11 isolates from the Red Sea, including the first strain of the SAR11 Ib clade.

    Science.gov (United States)

    Jimenez-Infante, Francy; Ngugi, David Kamanda; Vinu, Manikandan; Blom, Jochen; Alam, Intikhab; Bajic, Vladimir B; Stingl, Ulrich

    2017-07-01

    The SAR11 clade (Pelagibacterales) is a diverse group that forms a monophyletic clade within the Alphaproteobacteria, and constitutes up to one third of all prokaryotic cells in the photic zone of most oceans. Pelagibacterales are very abundant in the warm and highly saline surface waters of the Red Sea, raising the question of adaptive traits of SAR11 populations in this water body and warmer oceans through the world. In this study, two pure cultures were successfully obtained from surface waters on the Red Sea: one isolate of subgroup Ia and one of the previously uncultured SAR11 Ib lineage. The novel genomes were very similar to each other and to genomes of isolates of SAR11 subgroup Ia (Ia pan-genome), both in terms of gene content and synteny. Among the genes that were not present in the Ia pan-genome, 108 (RS39, Ia) and 151 genes (RS40, Ib) were strain specific. Detailed analyses showed that only 51 (RS39, Ia) and 55 (RS40, Ib) of these strain-specific genes had not reported before on genome fragments of Pelagibacterales. Further analyses revealed the potential production of phosphonates by some SAR11 members and possible adaptations for oligotrophic life, including pentose sugar utilization and adhesion to marine particulate matter. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Genomic Characterization of Two Novel SAR11 Isolates From the Red Sea, Including the First Strain of the SAR11 Ib clade

    KAUST Repository

    Jimenez Infante, Francy M.

    2017-06-22

    The SAR11 clade (Pelagibacterales) is a diverse group that forms a monophyletic clade within the Alphaproteobacteria, and constitutes up to one third of all prokaryotic cells in the photic zone of most oceans. Pelagibacterales are very abundant in the warm and highly saline surface waters of the Red Sea, raising the question of adaptive traits of SAR11 populations in this water body and warmer oceans through the world. In this study, two pure cultures were successfully obtained from surface waters on the Red Sea, one isolate of subgroup Ia and one of the previously uncultured SAR11 Ib lineage. The novel genomes were very similar to each other and to genomes of isolates of SAR11 subgroup Ia (Ia pan-genome), both in terms of gene content and synteny. Among the genes that were not present in the Ia pan-genome, 108 (RS39, Ia) and 151 genes (RS40, Ib) were strain-specific. Detailed analyses showed that only 51 (RS39, Ia) and 55 (RS40, Ib) of these strain-specific genes had not reported before on genome fragments of Pelagibacterales. Further analyses revealed the potential production of phosphonates by some SAR11 members and possible adaptations for oligotrophic life, including pentose sugar utilization and adhesion to marine particulate matter.

  14. Genomic Characterization of Two Novel SAR11 Isolates From the Red Sea, Including the First Strain of the SAR11 Ib clade

    KAUST Repository

    Jimenez Infante, Francy M.; Ngugi, David; Vinu, Manikandan; Blom, Jochen; Alam, Intikhab; Bajic, Vladimir B.; Stingl, Ulrich

    2017-01-01

    The SAR11 clade (Pelagibacterales) is a diverse group that forms a monophyletic clade within the Alphaproteobacteria, and constitutes up to one third of all prokaryotic cells in the photic zone of most oceans. Pelagibacterales are very abundant in the warm and highly saline surface waters of the Red Sea, raising the question of adaptive traits of SAR11 populations in this water body and warmer oceans through the world. In this study, two pure cultures were successfully obtained from surface waters on the Red Sea, one isolate of subgroup Ia and one of the previously uncultured SAR11 Ib lineage. The novel genomes were very similar to each other and to genomes of isolates of SAR11 subgroup Ia (Ia pan-genome), both in terms of gene content and synteny. Among the genes that were not present in the Ia pan-genome, 108 (RS39, Ia) and 151 genes (RS40, Ib) were strain-specific. Detailed analyses showed that only 51 (RS39, Ia) and 55 (RS40, Ib) of these strain-specific genes had not reported before on genome fragments of Pelagibacterales. Further analyses revealed the potential production of phosphonates by some SAR11 members and possible adaptations for oligotrophic life, including pentose sugar utilization and adhesion to marine particulate matter.

  15. Fine scale mapping of genomic introgressions within the Drosophila yakuba clade.

    Science.gov (United States)

    Turissini, David A; Matute, Daniel R

    2017-09-01

    The process of speciation involves populations diverging over time until they are genetically and reproductively isolated. Hybridization between nascent species was long thought to directly oppose speciation. However, the amount of interspecific genetic exchange (introgression) mediated by hybridization remains largely unknown, although recent progress in genome sequencing has made measuring introgression more tractable. A natural place to look for individuals with admixed ancestry (indicative of introgression) is in regions where species co-occur. In west Africa, D. santomea and D. yakuba hybridize on the island of São Tomé, while D. yakuba and D. teissieri hybridize on the nearby island of Bioko. In this report, we quantify the genomic extent of introgression between the three species of the Drosophila yakuba clade (D. yakuba, D. santomea), D. teissieri). We sequenced the genomes of 86 individuals from all three species. We also developed and applied a new statistical framework, using a hidden Markov approach, to identify introgression. We found that introgression has occurred between both species pairs but most introgressed segments are small (on the order of a few kilobases). After ruling out the retention of ancestral polymorphism as an explanation for these similar regions, we find that the sizes of introgressed haplotypes indicate that genetic exchange is not recent (>1,000 generations ago). We additionally show that in both cases, introgression was rarer on X chromosomes than on autosomes which is consistent with sex chromosomes playing a large role in reproductive isolation. Even though the two species pairs have stable contemporary hybrid zones, providing the opportunity for ongoing gene flow, our results indicate that genetic exchange between these species is currently rare.

  16. Identifikasi Secara Serologi Galur Virus Flu Burung Subtipe H5N1 Clade 2.1.3 dan Clade 2.3.2 pada Ayam Petelur (SEROLOGICAL IDENTIFICATION OF AVIAN INFLUENZA STRAIN VIRUS SUBTYPE H5N1 CLADE 2.1.3 AND CLADE 2.3.2 FROM LAYER

    Directory of Open Access Journals (Sweden)

    Aprilia Kusumastuti

    2015-10-01

    Full Text Available The aim of the study was to know avian influenza (AI infection in field by using serology test in threemarketing area of AI vaccines. Haemagglutination inhibition methode was used in this test. There werefour antigen strains of AI subtype H5N1 clade 2.1.3 (AIstrainA/Chicken/West Java/PWT-WIJ/2006, AIstrain A/Chicken/Garut/BBVW-223/2007, AI strain A/Chicken/West Java-Nagrak/30/2007, and AI strainA/Chicken/Pekalongan/BBVW-208/2007 and 2 antigen strains of AI subtype H5N1 clade 2.3.2 (AI strainA/duck/Sukoharjo/BBVW-1428-9/2012 and AI strain A/duck/Sleman/BBVW-1463-10/2012 was used inthis study for HI test. The result presents that 93,33% chicken farms in three marketing area of PT. SanbioLaboratories have positive antibody titre to AI subtype H5N1 clade 2.1.3. This titre may be obtained fromAI clade 2.1.3 vaccination. From 15 samples, 92,86% are positive to AI subtype H5N1 clade 2.3.2A/duck/Sukoharjo/BBVW-1428-9/2012 and 92,31% are positive to A/duck/Sleman/BBVW-1463-10/2012 evenwithout AI clade 2.3.2 vaccination. This antibody titre may be obtained from AI clade 2.1.3 vaccine crossprotection or field infection.

  17. SRP-2 is a cross-class inhibitor that participates in postembryonic development of the nematode Caenorhabditis elegans: initial characterization of the clade L serpins.

    Science.gov (United States)

    Pak, Stephen C; Kumar, Vasantha; Tsu, Christopher; Luke, Cliff J; Askew, Yuko S; Askew, David J; Mills, David R; Brömme, Dieter; Silverman, Gary A

    2004-04-09

    High molecular weight serpins are members of a large superfamily of structurally conserved proteins that inactivate target proteinases by a suicide substrate-like mechanism. In vertebrates, different clades of serpins distribute predominantly to either the intracellular or extracellular space. Although much is known about the function, structure, and inhibitory mechanism of circulating serpins such as alpha(1)-antitrypsin (SERPINA1) and antithrombin III (SERPINC1), relatively little is known about the function of the vertebrate intracellular (clade B) serpins. To gain a better understanding of the biology of the intracellular serpins, we initiated a comparative genomics study using Caenorhabditis elegans as a model system. A screen of the C. elegans genomic and cDNA databases revealed nine serpin genes, tandemly arrayed on chromosome V. Although the C. elegans serpins represent a unique clade (L), they share significant functional homology with members of the clade B group of intracellular serpins, since they lack typical N-terminal signal peptides and reside intracellularly. To determine whether nematode serpins function as proteinase inhibitors, one family member, srp-2, was chosen for further characterization. Biochemical analysis of recombinant SRP-2 protein revealed SRP-2 to be a dual cross-class inhibitor of the apoptosis-related serine proteinase, granzyme B, and the lysosomal cysteine proteinases, cathepsins K, L, S, and V. Analysis of temporal and spatial expression indicated that SRP-2 was present during early embryonic development and highly expressed in the intestine and hypoderm of larval and adult worms. Transgenic animals engineered to overexpress SRP-2 were slow growing and/or arrested at the first, second, or third larval stages. These data suggest that perturbations of serpin-proteinase balance are critical for correct postembryonic development in C. elegans.

  18. Evolutionary and biotechnology implications of plastid genome variation in the inverted-repeat-lacking clade of legumes.

    Science.gov (United States)

    Sabir, Jamal; Schwarz, Erika; Ellison, Nicholas; Zhang, Jin; Baeshen, Nabih A; Mutwakil, Muhammed; Jansen, Robert; Ruhlman, Tracey

    2014-08-01

    Land plant plastid genomes (plastomes) provide a tractable model for evolutionary study in that they are relatively compact and gene dense. Among the groups that display an appropriate level of variation for structural features, the inverted-repeat-lacking clade (IRLC) of papilionoid legumes presents the potential to advance general understanding of the mechanisms of genomic evolution. Here, are presented six complete plastome sequences from economically important species of the IRLC, a lineage previously represented by only five completed plastomes. A number of characters are compared across the IRLC including gene retention and divergence, synteny, repeat structure and functional gene transfer to the nucleus. The loss of clpP intron 2 was identified in one newly sequenced member of IRLC, Glycyrrhiza glabra. Using deeply sequenced nuclear transcriptomes from two species helped clarify the nature of the functional transfer of accD to the nucleus in Trifolium, which likely occurred in the lineage leading to subgenus Trifolium. Legumes are second only to cereal crops in agricultural importance based on area harvested and total production. Genetic improvement via plastid transformation of IRLC crop species is an appealing proposition. Comparative analyses of intergenic spacer regions emphasize the need for complete genome sequences for developing transformation vectors for plastid genetic engineering of legume crops. © 2014 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  19. DOG1-like genes in cereals: investigation of their function by means of ectopic expression in Arabidopsis.

    Science.gov (United States)

    Ashikawa, Ikuo; Abe, Fumitaka; Nakamura, Shingo

    2013-07-01

    The Arabidopsis gene DOG1 (AtDOG1) functions in seed dormancy and in sugar signaling. Little is known about the structural and functional features of plant genes homologous to AtDOG1, except for one type (clade 1) of Triticeae AtDOG1-like genes, which was previously demonstrated to be functionally orthologous to AtDOG1. Here, through phylogenetic, structural, and functional analyses of cereal AtDOG1-like genes, we characterized their features: these genes exist as a gene family that can be classified into five distinct clades (1-5). Of these, AtDOG1-like genes in clades 1-4 have a similar architecture to AtDOG1: they encode proteins with three conserved regions. In contrast, the clade 5 genes are distinct; their encoded proteins lack these conserved regions, but harbor domains that interact with DNA. Ectopic expression of the cereal AtDOG1-like genes of clades 2-4 in Arabidopsis demonstrated that like the clade 1 genes, they performed the same function as AtDOG1. The correlation between the depth of seed dormancy and the efficiency of sugar signaling in transgenic Arabidopsis conferred by genes in clades 1-4 suggests a close link in the underlying mechanisms between the seed dormancy and sugar signaling functions of AtDOG1. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Trypanosoma janseni n. sp. (Trypanosomatida: Trypanosomatidae isolated from Didelphis aurita (Mammalia: Didelphidae in the Atlantic Rainforest of Rio de Janeiro, Brazil: integrative taxonomy and phylogeography within the Trypanosoma cruzi clade

    Directory of Open Access Journals (Sweden)

    Camila Madeira Tavares Lopes

    Full Text Available BACKGROUND Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. OBJECTIVES We characterise a new species (Trypanosoma janseni n. sp. isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. METHODS The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp of the small subunit (18S ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. FINDINGS In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. CONCLUSIONS This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently

  1. Trypanosoma janseni n. sp. (Trypanosomatida: Trypanosomatidae) isolated from Didelphis aurita (Mammalia: Didelphidae) in the Atlantic Rainforest of Rio de Janeiro, Brazil: integrative taxonomy and phylogeography within the Trypanosoma cruzi clade.

    Science.gov (United States)

    Lopes, Camila Madeira Tavares; Menna-Barreto, Rubem Figueiredo Sadok; Pavan, Márcio Galvão; Pereira, Mirian Cláudia De Souza; Roque, André Luiz R

    2018-01-01

    Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. We characterise a new species (Trypanosoma janseni n. sp.) isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp) of the small subunit (18S) ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently know about the T. cruzi clade.

  2. Targeted sequencing of clade-specific markers from skin microbiomes for forensic human identification.

    Science.gov (United States)

    Schmedes, Sarah E; Woerner, August E; Novroski, Nicole M M; Wendt, Frank R; King, Jonathan L; Stephens, Kathryn M; Budowle, Bruce

    2018-01-01

    The human skin microbiome is comprised of diverse communities of bacterial, eukaryotic, and viral taxa and contributes millions of additional genes to the repertoire of human genes, affecting human metabolism and immune response. Numerous genetic and environmental factors influence the microbiome composition and as such contribute to individual-specific microbial signatures which may be exploited for forensic applications. Previous studies have demonstrated the potential to associate skin microbial profiles collected from touched items to their individual owner, mainly using unsupervised methods from samples collected over short time intervals. Those studies utilize either targeted 16S rRNA or shotgun metagenomic sequencing to characterize skin microbiomes; however, these approaches have limited species and strain resolution and susceptibility to stochastic effects, respectively. Clade-specific markers from the skin microbiome, using supervised learning, can predict individual identity using skin microbiomes from their respective donors with high accuracy. In this study the hidSkinPlex is presented, a novel targeted sequencing method using skin microbiome markers developed for human identification. The hidSkinPlex (comprised of 286 bacterial (and phage) family-, genus-, species-, and subspecies-level markers), initially was evaluated on three bacterial control samples represented in the panel (i.e., Propionibacterium acnes, Propionibacterium granulosum, and Rothia dentocariosa) to assess the performance of the multiplex. The hidSkinPlex was further evaluated for prediction purposes. The hidSkinPlex markers were used to attribute skin microbiomes collected from eight individuals from three body sites (i.e., foot (Fb), hand (Hp) and manubrium (Mb)) to their host donor. Supervised learning, specifically regularized multinomial logistic regression and 1-nearest-neighbor classification were used to classify skin microbiomes to their hosts with up to 92% (Fb), 96% (Mb

  3. Effect of Neuraminidase Inhibitor–Resistant Mutations on Pathogenicity of Clade 2.2 A/Turkey/15/06 (H5N1) Influenza Virus in Ferrets

    OpenAIRE

    Ilyushina, Natalia A.; Seiler, Jon P.; Rehg, Jerold E.; Webster, Robert G.; Govorkova, Elena A.

    2010-01-01

    The acquisition of neuraminidase (NA) inhibitor resistance by H5N1 influenza viruses has serious clinical implications, as this class of drugs can be an essential component of pandemic control measures. The continuous evolution of the highly pathogenic H5N1 influenza viruses results in the emergence of natural NA gene variations whose impact on viral fitness and NA inhibitor susceptibility are poorly defined. We generated seven genetically stable recombinant clade 2.2 A/Turkey/15/06-like (H5N...

  4. The Transcriptomes of Xiphinema index and Longidorus elongatus Suggest Independent Acquisition of Some Plant Parasitism Genes by Horizontal Gene Transfer in Early-Branching Nematodes

    NARCIS (Netherlands)

    Danchin, Etienne G.J.; Perfus-Barbeoch, Laetitia; Rancurel, Corinne; Thorpe, Peter; Rocha, Da Martine; Bajew, Simon; Neilson, Roy; Sokolova, Elena; Silva, Da Corinne; Guy, Julie; Labadie, Karine; Esmenjaud, Daniel; Helder, Hans; Jones, John T.; Eves-van den Akker, Sebastian

    2017-01-01

    Nematodes have evolved the ability to parasitize plants on at least four independent occasions, with plant parasites present in Clades 1, 2, 10 and 12 of the phylum. In the case of Clades 10 and 12, horizontal gene transfer of plant cell wall degrading enzymes from bacteria and fungi has been

  5. Phylogeny and taxonomy of the North American clade of the Ceratocystis fimbriata complex.

    Science.gov (United States)

    Johnson, Jason A; Harrington, Thomas C; Engelbrecht, C J B

    2005-01-01

    Ceratocystis fimbriata is a widely distributed, plant pathogenic fungus that causes wilts and cankers on many woody hosts. Earlier phylogenetic analyses of DNA sequences revealed three geographic clades within the C. fimbriata complex that are centered respectively in North America, Latin America and Asia. This study looked for cryptic species within the North American clade. The internal transcribed spacer regions (ITS) of the rDNA were sequenced, and phylogenetic analysis indicated that most isolates from the North American clade group into four host-associated lineages, referred to as the aspen, hickory, oak and cherry lineages, which were isolated primarily from wounds or diseased trees of Populus, Carya, Quercus and Prunus, respectively. A single isolate collected from P. serotina in Wisconsin had a unique ITS sequence. Allozyme electromorphs also were highly polymorphic within the North American clade, and the inferred phylogenies from these data were congruent with the ITS-rDNA analyses. In pairing experiments isolates from the aspen, hickory, oak and cherry lineages were interfertile only with other isolates from their respective lineages. Inoculation experiments with isolates of the four host-associated groupings showed strong host specialization by isolates from the aspen and hickory lineages on Populus tremuloides and Carya illinoensis, respectively, but isolates from the oak and cherry lineages did not consistently reveal host specialization. Morphological features distinguish isolates in the North American clade from those of the Latin American clade (including C. fimbriata sensu stricto). Based on the phylogenetic evidence, interfertility, host specialization and morphology, the oak and cherry lineages are recognized as the earlier described C. variospora, the poplar lineage as C. populicola sp. nov., and the hickory lineage as C. caryae sp. nov. A new species associated with the bark beetle Scolytus quadrispinosus on Carya is closely related to C

  6. Phylogenomic analysis of Candidatus ‘Izimaplasma’ species: free-living representatives from a Tenericutes clade found in methane seeps

    KAUST Repository

    Skennerton, Connor T.

    2016-04-08

    Tenericutes are a unique class of bacteria that lack a cell wall and are typically parasites or commensals of eukaryotic hosts. Environmental 16S rDNA surveys have identified a number of tenericute clades in diverse environments, introducing the possibility that these Tenericutes may represent non-host-associated, free-living microorganisms. Metagenomic sequencing of deep-sea methane seep sediments resulted in the assembly of two genomes from a Tenericutes-affiliated clade currently known as \\'NB1-n\\' (SILVA taxonomy) or \\'RF3\\' (Greengenes taxonomy). Metabolic reconstruction revealed that, like cultured members of the Mollicutes, these \\'NB1-n\\' representatives lack a tricarboxylic acid cycle and instead use anaerobic fermentation of simple sugars for substrate level phosphorylation. Notably, the genomes also contained a number of unique metabolic features including hydrogenases and a simplified electron transport chain containing an RNF complex, cytochrome bd oxidase and complex I. On the basis of the metabolic potential predicted from the annotated genomes, we devised an anaerobic enrichment media that stimulated the growth of these Tenericutes at 10 °C, resulting in a mixed culture where these organisms represented ∼60% of the total cells by targeted fluorescence in situ hybridization (FISH). Visual identification by FISH confirmed these organisms were not directly associated with Eukaryotes and electron cryomicroscopy of cells in the enrichment culture confirmed an ultrastructure consistent with the defining phenotypic property of Tenericutes, with a single membrane and no cell wall. On the basis of their unique gene content, phylogenetic placement and ultrastructure, we propose these organisms represent a novel class within the Tenericutes, and suggest the names Candidatus \\'Izimaplasma sp. HR1\\' and Candidatus \\'Izimaplasma sp. HR2\\' for the two genome representatives.

  7. A clade uniting the green algae Mesostigma viride and Chlorokybus atmophyticus represents the deepest branch of the Streptophyta in chloroplast genome-based phylogenies

    Directory of Open Access Journals (Sweden)

    Turmel Monique

    2007-01-01

    Full Text Available Abstract Background The Viridiplantae comprise two major phyla: the Streptophyta, containing the charophycean green algae and all land plants, and the Chlorophyta, containing the remaining green algae. Despite recent progress in unravelling phylogenetic relationships among major green plant lineages, problematic nodes still remain in the green tree of life. One of the major issues concerns the scaly biflagellate Mesostigma viride, which is either regarded as representing the earliest divergence of the Streptophyta or a separate lineage that diverged before the Chlorophyta and Streptophyta. Phylogenies based on chloroplast and mitochondrial genomes support the latter view. Because some green plant lineages are not represented in these phylogenies, sparse taxon sampling has been suspected to yield misleading topologies. Here, we describe the complete chloroplast DNA (cpDNA sequence of the early-diverging charophycean alga Chlorokybus atmophyticus and present chloroplast genome-based phylogenies with an expanded taxon sampling. Results The 152,254 bp Chlorokybus cpDNA closely resembles its Mesostigma homologue at the gene content and gene order levels. Using various methods of phylogenetic inference, we analyzed amino acid and nucleotide data sets that were derived from 45 protein-coding genes common to the cpDNAs of 37 green algal/land plant taxa and eight non-green algae. Unexpectedly, all best trees recovered a robust clade uniting Chlorokybus and Mesostigma. In protein trees, this clade was sister to all streptophytes and chlorophytes and this placement received moderate support. In contrast, gene trees provided unequivocal support to the notion that the Mesostigma + Chlorokybus clade represents the earliest-diverging branch of the Streptophyta. Independent analyses of structural data (gene content and/or gene order and of subsets of amino acid data progressively enriched in slow-evolving sites led us to conclude that the latter topology

  8. Protection level of AI H5N1 vaccine clade 2.1.3 commercial against AI H5N1 clade 2.3.2 virus from Ducks to SPF chicken in laboratory conditions

    Directory of Open Access Journals (Sweden)

    Indriani R

    2015-03-01

    Full Text Available Highly Pathogenic Avian Influenza (HPAI subtype H5N1 clade 2.3.2 has infected chickens in farms, causing mortality and a decrease in egg production. Vaccination is one of the strategies to control disease of AI subtype H5N1. AI H5N1 clade 2.1.3 vaccine is available commercially. The effectiveness of two vaccines of AI H5N1 clade 2.1.3 (product A and B, and AI H5N1 clade 2.3.2 (Sukoharjo against AI H5N1 clade 2.3.2 (Sukoharjo virus SPF chickens was tested in laboratory. Four groups of SPF chickens were used in this study, there were (1 vaccinated with H5N1 clade 2.1.3 (product A, (2 vaccinated with H5N1 clade 2.1.3 (product B, (3 vaccinated with AI H5N1 clade 2.3.2 and (4 unvaccinated (as a control. Each vaccinated group consisted of 10 chicken except 8 chicken for control group. SPF chicken were vaccinated with 1 dose of vaccine at 3 weeks olds, and then after 3 weeks post vaccination (at 6 weeks olds. All group of chicken were challenged with 106 EID50 per 0.1 ml via intranasal. The results showed, chicken vaccinated with H5N1 clade 2.1.3 product A and B gave 100 and 80% protection respectively, but showed challenged virus shedding, whereas vaccine of H5N1 clade 2.3.2 gave 100% protection from mortality and without virus shedding. Vaccines of AI H5N1 clade 2.1.3 product A was better than vaccine product B, and when chicken vaccinated against H5N1 clade 2.3.2, H5N1 clade 2.3.2 vaccine was the best to be used. In order to protect chicken from AI subtype H5N1 clade 2.1.3 and 2.3.2 in the field, a bivalent vaccine of H5N1 clade 2.1.3 and 2.3.2 subtypes should be developed.

  9. Protection of White Leghorn chickens by U.S. emergency H5 vaccination against clade 2.3.4.4 H5N2 high pathogenicity avian influenza virus.

    Science.gov (United States)

    Bertran, Kateri; Balzli, Charles; Lee, Dong-Hun; Suarez, David L; Kapczynski, Darrell R; Swayne, David E

    2017-11-01

    During December 2014-June 2015, the U.S. experienced a high pathogenicity avian influenza (HPAI) outbreak caused by clade 2.3.4.4 H5Nx Goose/Guangdong lineage viruses with devastating consequences for the poultry industry. Three vaccines, developed based on updating existing registered vaccines or currently licensed technologies, were evaluated for possible use: an inactivated reverse genetics H5N1 vaccine (rgH5N1) and an RNA particle vaccine (RP-H5), both containing the hemagglutinin gene of clade 2.3.4.4 strain, and a recombinant herpesvirus turkey vectored vaccine (rHVT-H5) containing the hemagglutinin gene of clade 2.2 strain. The efficacy of the three vaccines, alone or in combination, was assessed in White Leghorn chickens against clade 2.3.4.4 H5N2 HPAI virus challenge. In Study 1, single (rHVT-H5) and prime-boost (rHVT-H5+rgH5N1 or rHVT-H5+RP-H5) vaccination strategies protected chickens with high levels of protective immunity and significantly reduced virus shedding. In Study 2, single vaccination with either rgH5N1 or RP-H5 vaccines provided clinical protection in adult chickens and significantly reduced virus shedding. In Study 3, double rgH5N1 vaccination protected adult chickens from clinical signs and mortality when challenged 20weeks post-boost, with high levels of long-lasting protective immunity and significantly reduced virus shedding. These studies support the use of genetically related vaccines, possibly in combination with a broad protective priming vaccine, for emergency vaccination programs against clade 2.3.4.4 H5Nx HPAI virus in young and adult layer chickens. Published by Elsevier Ltd.

  10. Production of sophorolipids biosurfactants by multiple species of the Starmerella (Candida) bombicola yeast clade

    Science.gov (United States)

    Sophorolipid production was tested for 26 strains representing 19 species of the Starmerella yeast clade, including S. bombicola and Candida apicola, which were previously reported to produce sophorolipids. Five of the 19 species tested showed significant production of sophorolipids: S. bombicola, ...

  11. Genetic variation within Symbiodinium clade B from the coral genus Madracis in the Caribbean (Netherlands Antilles)

    NARCIS (Netherlands)

    Diekmann, O.E.; Olsen, J.L.; Stam, W.T.; Bak, R.P M

    The internal transcribed spacer (ITS) region was sequenced in symbiotic dinoflagellates (zooxanthellae) from five morphospecies in the genus Madracis. The phylogeny of the symbionts is congruent with a companion phylogeny of the coral host. Comparison with known clade B symbiont ITS types reveals

  12. Full-Genome Sequence of a Novel Varicella-Zoster Virus Clade Isolated in Mexico.

    Science.gov (United States)

    Garcés-Ayala, Fabiola; Rodríguez-Castillo, Araceli; Ortiz-Alcántara, Joanna María; Gonzalez-Durán, Elizabeth; Segura-Candelas, José Miguel; Pérez-Agüeros, Sandra Ivette; Escobar-Escamilla, Noé; Méndez-Tenorio, Alfonso; Diaz-Quiñonez, José Alberto; Ramirez-González, José Ernesto

    2015-07-09

    Varicella-zoster virus (VZV) is a member of the Herpesviridae family, which causes varicella (chicken pox) and herpes zoster (shingles) in humans. Here, we report the complete genome sequence of varicella-zoster virus, isolated from a vesicular fluid sample, revealing the circulation of VZV clade VIII in Mexico. Copyright © 2015 Garcés-Ayala et al.

  13. Full-Genome Sequence of a Novel Varicella-Zoster Virus Clade Isolated in Mexico

    OpenAIRE

    Garc?s-Ayala, Fabiola; Rodr?guez-Castillo, Araceli; Ortiz-Alc?ntara, Joanna Mar?a; Gonzalez-Dur?n, Elizabeth; Segura-Candelas, Jos? Miguel; P?rez-Ag?eros, Sandra Ivette; Escobar-Escamilla, No?; M?ndez-Tenorio, Alfonso; Diaz-Qui?onez, Jos? Alberto; Ramirez-Gonz?lez, Jos? Ernesto

    2015-01-01

    Varicella-zoster virus (VZV) is a member of the Herpesviridae family, which causes varicella (chicken pox) and herpes zoster (shingles) in humans. Here, we report the complete genome sequence of varicella-zoster virus, isolated from a vesicular fluid sample, revealing the circulation of VZV clade VIII in Mexico.

  14. Full-Genome Sequence of a Novel Varicella-Zoster Virus Clade Isolated in Mexico

    Science.gov (United States)

    Rodríguez-Castillo, Araceli; Ortiz-Alcántara, Joanna María; Gonzalez-Durán, Elizabeth; Segura-Candelas, José Miguel; Pérez-Agüeros, Sandra Ivette; Escobar-Escamilla, Noé; Méndez-Tenorio, Alfonso; Diaz-Quiñonez, José Alberto

    2015-01-01

    Varicella-zoster virus (VZV) is a member of the Herpesviridae family, which causes varicella (chicken pox) and herpes zoster (shingles) in humans. Here, we report the complete genome sequence of varicella-zoster virus, isolated from a vesicular fluid sample, revealing the circulation of VZV clade VIII in Mexico. PMID:26159533

  15. Molecular phylogeny of the parasitic dinoflagellate Chytriodinium within the Gymnodinium clade (Gymnodiniales, Dinophyceae)

    DEFF Research Database (Denmark)

    Gómez, Fernando; Skovgaard, Alf

    2015-01-01

    for the Atlantic Chytriodinium sp. The first complete small subunit ribosomal DNA (SSU rDNA) of the Atlantic Chytriodinium sp. suggests that the specimens belong to an undescribed species. This is the first evidence of the split of the Gymnodinium clade: one for the parasitic forms of Chytriodiniaceae...

  16. EVOLUTION OF NUCLEAR RDNA ITS SEQUENCES IN THE CLADOPHORA ALBIDA/SERICEA CLADE (CHLOROPHYTA)

    NARCIS (Netherlands)

    BAKKER, FT; OLSEN, JL; STAM, WT

    Ribosomal DNA ITS sequences were compared among 13 different species and biogeographic isolates from the monophyletic ''abbida/sericea clade'' in the green algal genus Cladophora. Six distinct ITS sequence types were found, characterized by multiple insertions and deletions and high levels of

  17. Effect of salt on the metabolism of 'Candidatus Accumulibacter' clade I and II

    NARCIS (Netherlands)

    Wang, Zhongwei; Dunne, Aislinn; van Loosdrecht, Mark C.M.; Saikaly, Pascal E.

    2018-01-01

    Saline wastewater is known to affect the performance of phosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) process. However, studies comparing the effect of salinity on different PAO clades are lacking. In this study, 'Candidatus Accumulibacter phosphatis'

  18. Pollen morphology within the Monodora clade, a diverse group of five African Annonaceae genera

    NARCIS (Netherlands)

    Couvreur, T.L.P.; Botermans, M.; Heuven, Van B.J.; Ham, van der R.W.J.M.

    2008-01-01

    Pollen morphology has played a major role in elucidating infrafamiliar-level systematics and evolution within Annonaceae, especially within the African genera. The Monodora clade is composed of five genera, Asteranthe, Hexalobus, Isolona, Monodora and Uvariastrum, which are restricted to Africa and

  19. Genomic differentiation among two strains of the PS1 clade isolated from geographically separated marine habitats

    KAUST Repository

    Jimenez Infante, Francy M.; Ngugi, David; Alam, Intikhab; Rashid, Mamoon; Ba Alawi, Wail; Kamau, Allan; Bajic, Vladimir B.; Stingl, Ulrich

    2014-01-01

    Using dilution-to-extinction cultivation, we isolated a strain affiliated with the PS1 clade from surface waters of the Red Sea. Strain RS24 represents the second isolate of this group of marine Alphaproteobacteria after IMCC14465 that was isolated

  20. Exploring genetic variation in the tomato (Solanum section Lycopersicon) clade by whole-genome sequencing

    NARCIS (Netherlands)

    Aflitos, S.A.; Schijlen, E.G.W.M.; Jong, de J.H.S.G.M.; Ridder, de D.; Smit, S.; Finkers, H.J.; Bakker, F.T.; Geest, van de H.C.; Lintel Hekkert, te B.; Haarst, van J.C.; Smits, L.W.M.; Koops, A.J.; Sanchez-Perez, M.J.; Heusden, van A.W.; Visser, R.G.F.; Schranz, M.E.; Peters, S.A.

    2014-01-01

    We explored genetic variation by sequencing a selection of 84 tomato accessions and related wild species representative for the Lycopersicon, Arcanum, Eriopersicon, and Neolycopersicon groups which has yielded a huge amount of precious data on sequence diversity in the tomato clade. Three new

  1. Exploring genetic variation in the tomato (Solanum section Lycopersicon) clade by whole-genome sequencing

    NARCIS (Netherlands)

    Aflitos, S.; Schijlen, E.; de Jong, H.; de Ridder, D.; Smit, S.; Finkers, R.; Wang, J.; Zhang, G.; Li, N.; Mao, L.; Bakker, F.; Dirks, R.; Breit, T.; Gravendeel, B.; Huits, H.; Struss, D.; Swanson-Wagner, R.; van Leeuwen, H.; van Ham, R.C.H.J.; Fito, L.; Guignier, L.; Sevilla, M.; Ellul, P.; Ganko, E.; Kapur, A.; Reclus, E.; de Geus, B.; van de Geest, H.; te Lintel Hekkert, B.; van Haarst, J.; Smits, L.; Koops, A.; Sanchez-Perez, G.; van Heusden, A.W.; Visser, R.; Quan, Z.; Min, J.; Liao, L.; Wang, X.; Wang, G.; Yue, Z.; Yang, X.; Xu, N.; Schranz, E.; Smets, E.; Vos, R.; Rauwerda, J.; Ursem, R.; Schuit, C.; Kerns, M.; van den Berg, J.; Vriezen, W.; Janssen, A.; Datema, E.; Jahrman, T.; Moquet, F.; Bonnet, J.; Peters, S.

    2014-01-01

    We explored genetic variation by sequencing a selection of 84 tomato accessions and related wild species representative of the Lycopersicon, Arcanum, Eriopersicon and Neolycopersicon groups, which has yielded a huge amount of precious data on sequence diversity in the tomato clade. Three new

  2. Expansion of a urethritis-associated Neisseria meningitidis clade in the United States with concurrent acquisition of N. gonorrhoeae alleles.

    Science.gov (United States)

    Retchless, Adam C; Kretz, Cécilia B; Chang, How-Yi; Bazan, Jose A; Abrams, A Jeanine; Norris Turner, Abigail; Jenkins, Laurel T; Trees, David L; Tzeng, Yih-Ling; Stephens, David S; MacNeil, Jessica R; Wang, Xin

    2018-03-02

    Increased reports of Neisseria meningitidis urethritis in multiple U.S. cities during 2015 have been attributed to the emergence of a novel clade of nongroupable N. meningitidis within the ST-11 clonal complex, the "U.S. NmNG urethritis clade". Genetic recombination with N. gonorrhoeae has been proposed to enable efficient sexual transmission by this clade. To understand the evolutionary origin and diversification of the U.S. NmNG urethritis clade, whole-genome phylogenetic analysis was performed to identify its members among the N. meningitidis strain collection from the Centers for Disease Control and Prevention, including 209 urogenital and rectal N. meningitidis isolates submitted by U.S. public health departments in eleven states starting in 2015. The earliest representatives of the U.S. NmNG urethritis clade were identified from cases of invasive disease that occurred in 2013. Among 209 urogenital and rectal isolates submitted from January 2015 to September 2016, the clade accounted for 189/198 male urogenital isolates, 3/4 female urogenital isolates, and 1/7 rectal isolates. In total, members of the clade were isolated in thirteen states between 2013 and 2016, which evolved from a common ancestor that likely existed during 2011. The ancestor contained N. gonorrhoeae-like alleles in three regions of its genome, two of which may facilitate nitrite-dependent anaerobic growth during colonization of urogenital sites. Additional gonococcal-like alleles were acquired as the clade diversified. Notably, one isolate contained a sequence associated with azithromycin resistance in N. gonorrhoeae, but no other gonococcal antimicrobial resistance determinants were detected. Interspecies genetic recombination contributed to the early evolution and subsequent diversification of the U.S. NmNG urethritis clade. Ongoing acquisition of N. gonorrhoeae alleles by the U.S. NmNG urethritis clade may facilitate the expansion of its ecological niche while also increasing the

  3. Comprehensive genomic analyses of the OM43 clade including a novel species from Red Sea indicate ecotype differentiation among marine methylotrophs

    KAUST Repository

    Jimenez Infante, Francy M.

    2015-12-11

    The OM43 clade within the family Methylophilaceae of Betaproteobacteria represents a group of methylotrophs playing important roles in the metabolism of C1 compounds in marine environments and other aquatic environments around the globe. Using dilution-to-extinction cultivation techniques, we successfully isolated a novel species of this clade (designated here as MBRS-H7) from the ultra-oligotrophic open ocean waters of the central Red Sea. Phylogenomic analyses indicate that MBRS-H7 is a novel species, which forms a distinct cluster together with isolate KB13 from Hawaii (H-RS cluster) that is separate from that represented by strain HTCC2181 (from the Oregon coast). Phylogenetic analyses using the robust 16S–23S internal transcribed spacer revealed a potential ecotype separation of the marine OM43 clade members, which was further confirmed by metagenomic fragment recruitment analyses that showed trends of higher abundance in low chlorophyll and/or high temperature provinces for the H-RS cluster, but a preference for colder, highly productive waters for the HTCC2181 cluster. This potential environmentally driven niche differentiation is also reflected in the metabolic gene inventories, which in the case of H-RS include those conferring resistance to high levels of UV irradiation, temperature, and salinity. Interestingly, we also found different energy conservation modules between these OM43 subclades, namely the existence of the NADH:quinone oxidoreductase NUO system in the H-RS and the non-homologous NQR system in HTCC2181, which might have implications on their overall energetic yields.

  4. Comprehensive genomic analyses of the OM43 clade including a novel species from Red Sea indicate ecotype differentiation among marine methylotrophs

    KAUST Repository

    Jimenez Infante, Francy M.; Ngugi, David; Vinu, Manikandan; Alam, Intikhab; Kamau, Allan; Blom, Jochen; Bajic, Vladimir B.; Stingl, Ulrich

    2015-01-01

    The OM43 clade within the family Methylophilaceae of Betaproteobacteria represents a group of methylotrophs playing important roles in the metabolism of C1 compounds in marine environments and other aquatic environments around the globe. Using dilution-to-extinction cultivation techniques, we successfully isolated a novel species of this clade (designated here as MBRS-H7) from the ultra-oligotrophic open ocean waters of the central Red Sea. Phylogenomic analyses indicate that MBRS-H7 is a novel species, which forms a distinct cluster together with isolate KB13 from Hawaii (H-RS cluster) that is separate from that represented by strain HTCC2181 (from the Oregon coast). Phylogenetic analyses using the robust 16S–23S internal transcribed spacer revealed a potential ecotype separation of the marine OM43 clade members, which was further confirmed by metagenomic fragment recruitment analyses that showed trends of higher abundance in low chlorophyll and/or high temperature provinces for the H-RS cluster, but a preference for colder, highly productive waters for the HTCC2181 cluster. This potential environmentally driven niche differentiation is also reflected in the metabolic gene inventories, which in the case of H-RS include those conferring resistance to high levels of UV irradiation, temperature, and salinity. Interestingly, we also found different energy conservation modules between these OM43 subclades, namely the existence of the NADH:quinone oxidoreductase NUO system in the H-RS and the non-homologous NQR system in HTCC2181, which might have implications on their overall energetic yields.

  5. Comprehensive Genomic Analyses of the OM43 Clade, Including a Novel Species from the Red Sea, Indicate Ecotype Differentiation among Marine Methylotrophs

    Science.gov (United States)

    Jimenez-Infante, Francy; Ngugi, David Kamanda; Vinu, Manikandan; Alam, Intikhab; Kamau, Allan Anthony; Blom, Jochen; Bajic, Vladimir B.

    2015-01-01

    The OM43 clade within the family Methylophilaceae of Betaproteobacteria represents a group of methylotrophs that play important roles in the metabolism of C1 compounds in marine environments and other aquatic environments around the globe. Using dilution-to-extinction cultivation techniques, we successfully isolated a novel species of this clade (here designated MBRS-H7) from the ultraoligotrophic open ocean waters of the central Red Sea. Phylogenomic analyses indicate that MBRS-H7 is a novel species that forms a distinct cluster together with isolate KB13 from Hawaii (Hawaii-Red Sea [H-RS] cluster) that is separate from the cluster represented by strain HTCC2181 (from the Oregon coast). Phylogenetic analyses using the robust 16S-23S internal transcribed spacer revealed a potential ecotype separation of the marine OM43 clade members, which was further confirmed by metagenomic fragment recruitment analyses that showed trends of higher abundance in low-chlorophyll and/or high-temperature provinces for the H-RS cluster but a preference for colder, highly productive waters for the HTCC2181 cluster. This potential environmentally driven niche differentiation is also reflected in the metabolic gene inventories, which in the case of the H-RS cluster include those conferring resistance to high levels of UV irradiation, temperature, and salinity. Interestingly, we also found different energy conservation modules between these OM43 subclades, namely, the existence of the NADH:quinone oxidoreductase complex I (NUO) system in the H-RS cluster and the nonhomologous NADH:quinone oxidoreductase (NQR) system in the HTCC2181 cluster, which might have implications for their overall energetic yields. PMID:26655752

  6. Phylogenetics and Gene Structure Dynamics of Polygalacturonase Genes in Aspergillus and Neurospora crassa

    Directory of Open Access Journals (Sweden)

    Jin-Sung Hong

    2013-09-01

    Full Text Available Polygalacturonase (PG gene is a typical gene family present in eukaryotes. Forty-nine PGs were mined from the genomes of Neurospora crassa and five Aspergillus species. The PGs were classified into 3 clades such as clade 1 for rhamno-PGs, clade 2 for exo-PGs and clade 3 for exo- and endo-PGs, which were further grouped into 13 sub-clades based on the polypeptide sequence similarity. In gene structure analysis, a total of 124 introns were present in 44 genes and five genes lacked introns to give an average of 2.5 introns per gene. Intron phase distribution was 64.5% for phase 0, 21.8% for phase 1, and 13.7% for phase 2, respectively. The introns varied in their sequences and their lengths ranged from 20 bp to 424 bp with an average of 65.9 bp, which is approximately half the size of introns in other fungal genes. There were 29 homologous intron blocks and 26 of those were sub-clade specific. Intron losses were counted in 18 introns in which no obvious phase preference for intron loss was observed. Eighteen introns were placed at novel positions, which is considerably higher than those of plant PGs. In an evolutionary sense both intron loss and gain must have taken place for shaping the current PGs in these fungi. Together with the small intron size, low conservation of homologous intron blocks and higher number of novel introns, PGs of fungal species seem to have recently undergone highly dynamic evolution.

  7. Global cooling as a driver of diversification in a major marine clade

    Science.gov (United States)

    Davis, Katie E.; Hill, Jon; Astrop, Tim I.; Wills, Matthew A.

    2016-10-01

    Climate is a strong driver of global diversity and will become increasingly important as human influences drive temperature changes at unprecedented rates. Here we investigate diversification and speciation trends within a diverse group of aquatic crustaceans, the Anomura. We use a phylogenetic framework to demonstrate that speciation rate is correlated with global cooling across the entire tree, in contrast to previous studies. Additionally, we find that marine clades continue to show evidence of increased speciation rates with cooler global temperatures, while the single freshwater clade shows the opposite trend with speciation rates positively correlated to global warming. Our findings suggest that both global cooling and warming lead to diversification and that habitat plays a role in the responses of species to climate change. These results have important implications for our understanding of how extant biota respond to ongoing climate change and are of particular importance for conservation planning of marine ecosystems.

  8. Mitochondrial molecular clocks and the origin of the major Otocephalan clades (Pisces: Teleostei)

    DEFF Research Database (Denmark)

    Peng, Zuogang; He, Shunping; Wang, Jun

    2006-01-01

    The Otocephala, a clade including ostariophysan and clupeomorph teleosts, represents about a quarter of total fish species diversity, with about 1000 genera and more than 7000 species. A series of recent papers have defended that the origin of this clade and of its major groups may be significantly...... otophysans could have originated before the splitting of the Pangean supercontinent is of extreme importance, since otophysan fishes are among the most useful animal groups for the determination of historical continental relationships. In the present work we examined divergence times for each major...... otocephalan group by an analysis of complete mtDNA sequences, in order to investigate if these divergence times support the hypotheses advanced in recent studies. The complete mtDNA sequences of nine representative non-otocephalan fish species and of twenty-one representative otocephalan species was compared...

  9. Molecular Phylogeny of the Parasitic Dinoflagellate Chytriodinium within the Gymnodinium Clade (Gymnodiniales, Dinophyceae).

    Science.gov (United States)

    Gómez, Fernando; Skovgaard, Alf

    2015-01-01

    The dinoflagellate genus Chytriodinium, an ectoparasite of copepod eggs, is reported for the first time in the North and South Atlantic Oceans. We provide the first large subunit rDNA (LSU rDNA) and Internal Transcribed Spacer 1 (ITS1) sequences, which were identical in both hemispheres for the Atlantic Chytriodinium sp. The first complete small subunit ribosomal DNA (SSU rDNA) of the Atlantic Chytriodinium sp. suggests that the specimens belong to an undescribed species. This is the first evidence of the split of the Gymnodinium clade: one for the parasitic forms of Chytriodiniaceae (Chytriodinium, Dissodinium), and other clade for the free-living species. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

  10. Pelagic larval duration predicts extinction risk in a freshwater fish clade

    OpenAIRE

    Douglas, Morgan; Keck, Benjamin P.; Ruble, Crystal; Petty, Melissa; Shute, J. R.; Rakes, Patrick; Hulsey, C. Darrin

    2013-01-01

    Pelagic larval duration (PLD) can influence evolutionary processes ranging from dispersal to extinction in aquatic organisms. Using estimates of PLD obtained from species of North American darters (Percidae: Etheostomatinae), we demonstrate that this freshwater fish clade exhibits surprising variation in PLD. Comparative analyses provide some evidence that higher stream gradients favour the evolution of shorter PLD. Additionally, similar to patterns in the marine fossil record in which lower ...

  11. Structural and antigenic variation among diverse clade 2 H5N1 viruses.

    Directory of Open Access Journals (Sweden)

    David A Shore

    Full Text Available Antigenic variation among circulating H5N1 highly pathogenic avian influenza A viruses mandates the continuous production of strain-specific pre-pandemic vaccine candidates and represents a significant challenge for pandemic preparedness. Here we assessed the structural, antigenic and receptor-binding properties of three H5N1 HPAI virus hemagglutinins, which were recently selected by the WHO as vaccine candidates [A/Egypt/N03072/2010 (Egypt10, clade 2.2.1, A/Hubei/1/2010 (Hubei10, clade 2.3.2.1 and A/Anhui/1/2005 (Anhui05, clade 2.3.4]. These analyses revealed that antigenic diversity among these three isolates was restricted to changes in the size and charge of amino acid side chains at a handful of positions, spatially equivalent to the antigenic sites identified in H1 subtype viruses circulating among humans. All three of the H5N1 viruses analyzed in this study were responsible for fatal human infections, with the most recently-isolated strains, Hubei10 and Egypt10, containing multiple residues in the receptor-binding site of the HA, which were suspected to enhance mammalian transmission. However, glycan-binding analyses demonstrated a lack of binding to human α2-6-linked sialic acid receptor analogs for all three HAs, reinforcing the notion that receptor-binding specificity contributes only partially to transmissibility and pathogenesis of HPAI viruses and suggesting that changes in host specificity must be interpreted in the context of the host and environmental factors, as well as the virus as a whole. Together, our data reveal structural linkages with phylogenetic and antigenic analyses of recently emerged H5N1 virus clades and should assist in interpreting the significance of future changes in antigenic and receptor-binding properties.

  12. Genome-wide comparison of cowpox viruses reveals a new clade related to Variola virus.

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    Piotr Wojtek Dabrowski

    Full Text Available Zoonotic infections caused by several orthopoxviruses (OPV like monkeypox virus or vaccinia virus have a significant impact on human health. In Europe, the number of diagnosed infections with cowpox viruses (CPXV is increasing in animals as well as in humans. CPXV used to be enzootic in cattle; however, such infections were not being diagnosed over the last decades. Instead, individual cases of cowpox are being found in cats or exotic zoo animals that transmit the infection to humans. Both animals and humans reveal local exanthema on arms and legs or on the face. Although cowpox is generally regarded as a self-limiting disease, immunosuppressed patients can develop a lethal systemic disease resembling smallpox. To date, only limited information on the complex and, compared to other OPV, sparsely conserved CPXV genomes is available. Since CPXV displays the widest host range of all OPV known, it seems important to comprehend the genetic repertoire of CPXV which in turn may help elucidate specific mechanisms of CPXV pathogenesis and origin. Therefore, 22 genomes of independent CPXV strains from clinical cases, involving ten humans, four rats, two cats, two jaguarundis, one beaver, one elephant, one marah and one mongoose, were sequenced by using massive parallel pyrosequencing. The extensive phylogenetic analysis showed that the CPXV strains sequenced clearly cluster into several distinct clades, some of which are closely related to Vaccinia viruses while others represent different clades in a CPXV cluster. Particularly one CPXV clade is more closely related to Camelpox virus, Taterapox virus and Variola virus than to any other known OPV. These results support and extend recent data from other groups who postulate that CPXV does not form a monophyletic clade and should be divided into multiple lineages.

  13. The Gondwana Breakup and the History of the Atlantic and Indian Oceans Unveils Two New Clades for Early Neobatrachian Diversification.

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    Annelise Frazão

    Full Text Available The largest anuran diversity belongs to the Neobatrachia, which harbor more than five thousand extant species. Here, we propose a new hypothesis for the historical aspects of the neobatrachian evolution with a formal biogeographical analysis. We selected 12 genes for 144 neobatrachian genera and four archaeobatrachian outgroups and performed a phylogenetic analysis using a maximum likelihood algorithm with the rapid bootstrap test. We also estimated divergence times for major lineages using a relaxed uncorrelated clock method. According to our time scale, the diversification of crown Neobatrachia began around the end of the Early Cretaceous. Our phylogenetic tree suggests that the first split of Neobatrachia is related to the geological events in the Atlantic and Indian Oceans. Hence, we propose names for these clades that indicate this connection, i.e., Atlanticanura and Indianura. The Atlanticanura is composed of three major neobatrachian lineages: Heleophrynidae, Australobatrachia and Nobleobatrachia. On the other hand, the Indianura consists of two major lineages: Sooglossoidea and Ranoides. The biogeographical analysis indicates that many neobatrachian splits occurred as a result of geological events such as the separation between South America and Africa, between India and the Seychelles, and between Australia and South America.

  14. Characterization of Phytophthora hybrids from ITS clade 6 associated with riparian ecosystems in South Africa and Australia.

    Science.gov (United States)

    Nagel, Jan H; Gryzenhout, Marieka; Slippers, Bernard; Wingfield, Michael J; Hardy, Giles E St J; Stukely, Michael J C; Burgess, Treena I

    2013-05-01

    Surveys of Australian and South African rivers revealed numerous Phytophthora isolates residing in clade 6 of the genus, with internal transcribed spacer (ITS) gene regions that were either highly polymorphic or unsequenceable. These isolates were suspected to be hybrids. Three nuclear loci, the ITS region, two single copy loci (antisilencing factor (ASF) and G protein alpha subunit (GPA)), and one mitochondrial locus (cytochrome oxidase c subunit I (coxI)) were amplified and sequenced to test this hypothesis. Abundant recombination within the ITS region was observed. This, combined with phylogenetic comparisons of the other three loci, confirmed the presence of four different hybrid types involving the three described parent species Phytophthora amnicola, Phytophthora thermophila, and Phytophthora taxon PgChlamydo. In all cases, only a single coxI allele was detected, suggesting that hybrids arose from sexual recombination. All the hybrid isolates were sterile in culture and all their physiological traits tended to resemble those of the maternal parents. Nothing is known regarding their host range or pathogenicity. Nonetheless, as several isolates from Western Australia were obtained from the rhizosphere soil of dying plants, they should be regarded as potential threats to plant health. The frequent occurrence of the hybrids and their parent species in Australia strongly suggests an Australian origin and a subsequent introduction into South Africa. Copyright © 2013 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  15. High throughput generation and characterization of replication-competent clade C transmitter-founder simian human immunodeficiency viruses.

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    Debashis Dutta

    Full Text Available Traditional restriction endonuclease-based cloning has been routinely used to generate replication-competent simian-human immunodeficiency viruses (SHIV and simian tropic HIV (stHIV. This approach requires the existence of suitable restriction sites or the introduction of nucleotide changes to create them. Here, using an In-Fusion cloning technique that involves homologous recombination, we generated SHIVs and stHIVs based on epidemiologically linked clade C transmitted/founder HIV molecular clones from Zambia. Replacing vif from these HIV molecular clones with vif of SIVmac239 resulted in chimeric genomes used to generate infectious stHIV viruses. Likewise, exchanging HIV env genes and introducing N375 mutations to enhance macaque CD4 binding site and cloned into a SHIVAD8-EO backbone. The generated SHIVs and stHIV were infectious in TZMbl and ZB5 cells, as well as macaque PBMCs. Therefore, this method can replace traditional methods and be a valuable tool for the rapid generation and testing of molecular clones of stHIV and SHIV based on primary clinical isolates will be valuable to generate rapid novel challenge viruses for HIV vaccine/cure studies.

  16. Phylogenetic relationships within anuran clade Terrarana, with emphasis on the placement of Brazilian Atlantic rainforest frogs genus Ischnocnema (Anura: Brachycephalidae).

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    Canedo, Clarissa; Haddad, Célio F B

    2012-11-01

    We present a phylogenetic hypothesis of the anuran clade Terrarana based on partial sequences of nuclear (Tyr and RAG1) and mitochondrial (12S, tRNA-Val, and 16S) genes, testing the monophyly of Ischnocnema and its species series. We performed maximum parsimony, maximum likelihood, and Bayesian inference analyses on 364 terminals: 11 outgroup terminals and 353 ingroup Terrarana terminals, including 139 Ischnocnema terminals (accounting for 29 of the 35 named Ischnocnema species) and 214 other Terrarana terminals within the families Brachycephalidae, Ceuthomantidae, Craugastoridae, and Eleutherodactylidae. Different optimality criteria produced similar results and mostly recovered the currently accepted families and genera. According to these topologies, Ischnocnema is not a monophyletic group. We propose new combinations for three species, relocating them to Pristimantis, and render Eleutherodactylus bilineatus Bokermann, 1975 incertae sedis status within Holoadeninae. The rearrangements in Ischnocnema place it outside the northernmost Brazilian Atlantic rainforest, where the fauna of Terrarana comprises typical Amazonian genera. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. An efficiently cleaved HIV-1 clade C Env selectively binds to neutralizing antibodies.

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    Saikat Boliar

    Full Text Available An ideal HIV-1 Env immunogen is expected to mimic the native trimeric conformation for inducing broadly neutralizing antibody responses. The native conformation is dependent on efficient cleavage of HIV-1 Env. The clade B isolate, JRFL Env is efficiently cleaved when expressed on the cell surface. Here, for the first time, we report the identification of a native clade C Env, 4-2.J41 that is naturally and efficiently cleaved on the cell surface as confirmed by its biochemical and antigenic characteristics. In addition to binding to several conformation-dependent neutralizing antibodies, 4-2.J41 Env binds efficiently to the cleavage-dependent antibody PGT151; thus validating its native cleaved conformation. In contrast, 4-2.J41 Env occludes non-neutralizing epitopes. The cytoplasmic-tail of 4-2.J41 Env plays an important role in maintaining its conformation. Furthermore, codon optimization of 4-2.J41 Env sequence significantly increases its expression while retaining its native conformation. Since clade C of HIV-1 is the prevalent subtype, identification and characterization of this efficiently cleaved Env would provide a platform for rational immunogen design.

  18. A novel Haemosporida clade at the rank of genus in North American cranes (Aves: Gruiformes).

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    Bertram, Miranda R; Hamer, Sarah A; Hartup, Barry K; Snowden, Karen F; Medeiros, Matthew C; Outlaw, Diana C; Hamer, Gabriel L

    2017-04-01

    The unicellular blood parasites in the order Haemosporida are highly diverse, infect many vertebrates, are responsible for a large disease burden among humans and animals, and have reemerged as an important model system to understand the evolutionary and ecological dynamics of host-parasite interactions. The phylogenetics and systematics of Haemosporida are limited by poor sampling of different vertebrate host taxa. We surveyed the Haemosporida of wild whooping cranes (Grus americana) and sandhill cranes (Grus canadensis) (Aves: Gruiformes) using a combination of morphological and molecular approaches. We identified Haemoproteus antigonis in blood smears based on published morphological descriptions. Phylogenetic analysis based on partial cytochrome b (cytb) and cytochrome oxidase (coI) sequences placed H. antigonis parasites in a novel clade, distinct from all avian Haemosporida genera for which cytb and/or coI sequences are available. Molecular clock and divergence estimates suggest this crane clade may represent a new genus. This is the first molecular description of H. antigonis and the first report of H. antigonis in wild whooping cranes, an endangered bird in North America. Further sampling of Haemosporida, especially from hosts of the Gruiformes and other poorly sampled orders, will help to resolve the relationship of the H. antigonis clade to other avian Haemosporida genera. Our study highlights the potential of sampling neglected host species to discover novel lineages of diverse parasite groups. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Repeated evolution of vertebrate pollination syndromes in a recently diverged Andean plant clade.

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    Lagomarsino, Laura P; Forrestel, Elisabeth J; Muchhala, Nathan; Davis, Charles C

    2017-08-01

    Although specialized interactions, including those involving plants and their pollinators, are often invoked to explain high species diversity, they are rarely explored at macroevolutionary scales. We investigate the dynamic evolution of hummingbird and bat pollination syndromes in the centropogonid clade (Lobelioideae: Campanulaceae), an Andean-centered group of ∼550 angiosperm species. We demonstrate that flowers hypothesized to be adapted to different pollinators based on flower color fall into distinct regions of morphospace, and this is validated by morphology of species with known pollinators. This supports the existence of pollination syndromes in the centropogonids, an idea corroborated by ecological studies. We further demonstrate that hummingbird pollination is ancestral, and that bat pollination has evolved ∼13 times independently, with ∼11 reversals. This convergence is associated with correlated evolution of floral traits within selective regimes corresponding to pollination syndrome. Collectively, our results suggest that floral morphological diversity is extremely labile, likely resulting from selection imposed by pollinators. Finally, even though this clade's rapid diversification is partially attributed to their association with vertebrate pollinators, we detect no difference in diversification rates between hummingbird- and bat-pollinated lineages. Our study demonstrates the utility of pollination syndromes as a proxy for ecological relationships in macroevolutionary studies of certain species-rich clades. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  20. Kretzoiarctos gen. nov., the oldest member of the giant panda clade.

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    Juan Abella

    Full Text Available The phylogenetic position of the giant panda, Ailuropoda melanoleuca (Carnivora: Ursidae: Ailuropodinae, has been one of the most hotly debated topics by mammalian biologists and paleontologists during the last century. Based on molecular data, it is currently recognized as a true ursid, sister-taxon of the remaining extant bears, from which it would have diverged by the Early Miocene. However, from a paleobiogeographic and chronological perspective, the origin of the giant panda lineage has remained elusive due to the scarcity of the available Miocene fossil record. Until recently, the genus Ailurarctos from the Late Miocene of China (ca. 8-7 mya was recognized as the oldest undoubted member of the Ailuropodinae, suggesting that the panda lineage might have originated from an Ursavus ancestor. The role of the purported ailuropodine Agriarctos, from the Miocene of Europe, in the origins of this clade has been generally dismissed due to the paucity of the available material. Here, we describe a new ailuropodine genus, Kretzoiarctos gen. nov., based on remains from two Middle Miocene (ca. 12-11 Ma Spanish localities. A cladistic analysis of fossil and extant members of the Ursoidea confirms the inclusion of the new genus into the Ailuropodinae. Moreover, Kretzoiarctos precedes in time the previously-known, Late Miocene members of the giant panda clade from Eurasia (Agriarctos and Ailurarctos. The former can be therefore considered the oldest recorded member of the giant panda lineage, which has significant implications for understanding the origins of this clade from a paleobiogeographic viewpoint.

  1. Predicting Mycobacterium tuberculosis Complex Clades Using Knowledge-Based Bayesian Networks

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    Minoo Aminian

    2014-01-01

    Full Text Available We develop a novel approach for incorporating expert rules into Bayesian networks for classification of Mycobacterium tuberculosis complex (MTBC clades. The proposed knowledge-based Bayesian network (KBBN treats sets of expert rules as prior distributions on the classes. Unlike prior knowledge-based support vector machine approaches which require rules expressed as polyhedral sets, KBBN directly incorporates the rules without any modification. KBBN uses data to refine rule-based classifiers when the rule set is incomplete or ambiguous. We develop a predictive KBBN model for 69 MTBC clades found in the SITVIT international collection. We validate the approach using two testbeds that model knowledge of the MTBC obtained from two different experts and large DNA fingerprint databases to predict MTBC genetic clades and sublineages. These models represent strains of MTBC using high-throughput biomarkers called spacer oligonucleotide types (spoligotypes, since these are routinely gathered from MTBC isolates of tuberculosis (TB patients. Results show that incorporating rules into problems can drastically increase classification accuracy if data alone are insufficient. The SITVIT KBBN is publicly available for use on the World Wide Web.

  2. Kretzoiarctos gen. nov., the oldest member of the giant panda clade.

    Science.gov (United States)

    Abella, Juan; Alba, David M; Robles, Josep M; Valenciano, Alberto; Rotgers, Cheyenn; Carmona, Raül; Montoya, Plinio; Morales, Jorge

    2012-01-01

    The phylogenetic position of the giant panda, Ailuropoda melanoleuca (Carnivora: Ursidae: Ailuropodinae), has been one of the most hotly debated topics by mammalian biologists and paleontologists during the last century. Based on molecular data, it is currently recognized as a true ursid, sister-taxon of the remaining extant bears, from which it would have diverged by the Early Miocene. However, from a paleobiogeographic and chronological perspective, the origin of the giant panda lineage has remained elusive due to the scarcity of the available Miocene fossil record. Until recently, the genus Ailurarctos from the Late Miocene of China (ca. 8-7 mya) was recognized as the oldest undoubted member of the Ailuropodinae, suggesting that the panda lineage might have originated from an Ursavus ancestor. The role of the purported ailuropodine Agriarctos, from the Miocene of Europe, in the origins of this clade has been generally dismissed due to the paucity of the available material. Here, we describe a new ailuropodine genus, Kretzoiarctos gen. nov., based on remains from two Middle Miocene (ca. 12-11 Ma) Spanish localities. A cladistic analysis of fossil and extant members of the Ursoidea confirms the inclusion of the new genus into the Ailuropodinae. Moreover, Kretzoiarctos precedes in time the previously-known, Late Miocene members of the giant panda clade from Eurasia (Agriarctos and Ailurarctos). The former can be therefore considered the oldest recorded member of the giant panda lineage, which has significant implications for understanding the origins of this clade from a paleobiogeographic viewpoint.

  3. Phylogeny of Elatinaceae and the Tropical Gondwanan Origin of the Centroplacaceae(Malpighiaceae, Elatinaceae Clade.

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    Liming Cai

    Full Text Available The flowering plant family Elatinaceae is a widespread aquatic lineage inhabiting temperate and tropical latitudes, including ∼35(-50 species. Its phylogeny remains largely unknown, compromising our understanding of its systematics. Moreover, this group is particularly in need of attention because the biogeography of most aquatic plant clades has yet to be investigated, resulting in uncertainty about whether aquatic plants show histories that deviate from terrestrial plants. We inferred the phylogeny of Elatinaceae from four DNA regions spanning 59 accessions across the family. An expanded sampling was used for molecular divergence time estimation and ancestral area reconstruction to infer the biogeography of Elatinaceae and their closest terrestrial relatives, Malpighiaceae and Centroplacaceae. The two genera of Elatinaceae, Bergia and Elatine, are monophyletic, but several traditionally recognized groups within the family are non-monophyletic. Our results suggest two ancient biogeographic events in the Centroplacaceae(Malpighiaceae, Elatinaceae clade involving western Gondwana, while Elatinaceae shows a more complicated biogeographic history with a high degree of continental endemicity. Our results indicate the need for further taxonomic investigation of Elatinaceae. Further, our study is one of few to implicate ancient Gondwanan biogeography in extant angiosperms, especially significant given the Centroplacaceae(Malpighiaceae, Elatinaceae clade's largely tropical distribution. Finally, Elatinaceae demonstrates long-term continental in situ diversification, which argues against recent dispersal as a universal explanation commonly invoked for aquatic plant distributions.

  4. Mitochondrial genome sequences reveal evolutionary relationships of the Phytophthora 1c clade species.

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    Lassiter, Erica S; Russ, Carsten; Nusbaum, Chad; Zeng, Qiandong; Saville, Amanda C; Olarte, Rodrigo A; Carbone, Ignazio; Hu, Chia-Hui; Seguin-Orlando, Andaine; Samaniego, Jose A; Thorne, Jeffrey L; Ristaino, Jean B

    2015-11-01

    Phytophthora infestans is one of the most destructive plant pathogens of potato and tomato globally. The pathogen is closely related to four other Phytophthora species in the 1c clade including P. phaseoli, P. ipomoeae, P. mirabilis and P. andina that are important pathogens of other wild and domesticated hosts. P. andina is an interspecific hybrid between P. infestans and an unknown Phytophthora species. We have sequenced mitochondrial genomes of the sister species of P. infestans and examined the evolutionary relationships within the clade. Phylogenetic analysis indicates that the P. phaseoli mitochondrial lineage is basal within the clade. P. mirabilis and P. ipomoeae are sister lineages and share a common ancestor with the Ic mitochondrial lineage of P. andina. These lineages in turn are sister to the P. infestans and P. andina Ia mitochondrial lineages. The P. andina Ic lineage diverged much earlier than the P. andina Ia mitochondrial lineage and P. infestans. The presence of two mitochondrial lineages in P. andina supports the hybrid nature of this species. The ancestral state of the P. andina Ic lineage in the tree and its occurrence only in the Andean regions of Ecuador, Colombia and Peru suggests that the origin of this species hybrid in nature may occur there.

  5. Phylogeny of the Ampelocissus-Vitis clade in Vitaceae supports the New World origin of the grape genus.

    Science.gov (United States)

    Liu, Xiu-Qun; Ickert-Bond, Stefanie M; Nie, Ze-Long; Zhou, Zhuo; Chen, Long-Qing; Wen, Jun

    2016-02-01

    The grapes and the close allies in Vitaceae are of great agronomic and economic importance. Our previous studies showed that the grape genus Vitis was closely related to three tropical genera, which formed the Ampelocissus-Vitis clade (including Vitis, Ampelocissus, Nothocissus and Pterisanthes). Yet the phylogenetic relationships of the four genera within this clade remain poorly resolved. Furthermore, the geographic origin of Vitis is still controversial, because the sampling of the close relatives of Vitis was too limited in the previous studies. This study reconstructs the phylogenetic relationships within the clade, and hypothesizes the origin of Vitis in a broader phylogenetic framework, using five plastid and two nuclear markers. The Ampelocissus-Vitis clade is supported to be composed of five main lineages. Vitis includes two described subgenera each as a monophyletic group. Ampelocissus is paraphyletic. The New World Ampelocissus does not form a clade and shows a complex phylogenetic relationship, with A. acapulcensis and A. javalensis forming a clade, and A. erdvendbergiana sister to Vitis. The majority of the Asian Ampelocissus species form a clade, within which Pterisanthes is nested. Pterisanthes is polyphyletic, suggesting that the lamellate inflorescence characteristic of the genus represents convergence. Nothocissus is sister to the clade of Asian Ampelocissus and Pterisanthes. The African Ampelocissus forms a clade with several Asian species. Based on the Bayesian dating and both the RASP and Lagrange analyses, Vitis is inferred to have originated in the New World during the late Eocene (39.4Ma, 95% HPD: 32.6-48.6Ma), then migrated to Eurasia in the late Eocene (37.3Ma, 95% HPD: 30.9-45.1Ma). The North Atlantic land bridges (NALB) are hypothesized to be the most plausible route for the Vitis migration from the New World to Eurasia, while intercontinental long distance dispersal (LDD) cannot be eliminated as a likely mechanism. Copyright © 2015

  6. Effect of neuraminidase inhibitor-resistant mutations on pathogenicity of clade 2.2 A/Turkey/15/06 (H5N1) influenza virus in ferrets.

    Science.gov (United States)

    Ilyushina, Natalia A; Seiler, Jon P; Rehg, Jerold E; Webster, Robert G; Govorkova, Elena A

    2010-05-27

    The acquisition of neuraminidase (NA) inhibitor resistance by H5N1 influenza viruses has serious clinical implications, as this class of drugs can be an essential component of pandemic control measures. The continuous evolution of the highly pathogenic H5N1 influenza viruses results in the emergence of natural NA gene variations whose impact on viral fitness and NA inhibitor susceptibility are poorly defined. We generated seven genetically stable recombinant clade 2.2 A/Turkey/15/06-like (H5N1) influenza viruses carrying NA mutations located either in the framework residues (E119A, H274Y, N294S) or in close proximity to the NA enzyme active site (V116A, I117V, K150N, Y252H). NA enzyme inhibition assays showed that NA mutations at positions 116, 117, 274, and 294 reduced susceptibility to oseltamivir carboxylate (IC(50)s increased 5- to 940-fold). Importantly, the E119A NA mutation (previously reported to confer resistance in the N2 NA subtype) was stable in the clade 2.2 H5N1 virus background and induced cross-resistance to oseltamivir carboxylate and zanamivir. We demonstrated that Y252H NA mutation contributed for decreased susceptibility of clade 2.2 H5N1 viruses to oseltamivir carboxylate as compared to clade 1 viruses. The enzyme kinetic parameters (V(max), K(m) and K(i)) of the avian-like N1 NA glycoproteins were highly consistent with their IC(50) values. None of the recombinant H5N1 viruses had attenuated virulence in ferrets inoculated with 10(6) EID(50) dose. Most infected ferrets showed mild clinical disease signs that differed in duration. However, H5N1 viruses carrying the E119A or the N294S NA mutation were lethal to 1 of 3 inoculated animals and were associated with significantly higher virus titers (Pinfluenza drugs that target different virus/host factors and can limit the emergence of resistance.

  7. Effect of neuraminidase inhibitor-resistant mutations on pathogenicity of clade 2.2 A/Turkey/15/06 (H5N1 influenza virus in ferrets.

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    Natalia A Ilyushina

    2010-05-01

    Full Text Available The acquisition of neuraminidase (NA inhibitor resistance by H5N1 influenza viruses has serious clinical implications, as this class of drugs can be an essential component of pandemic control measures. The continuous evolution of the highly pathogenic H5N1 influenza viruses results in the emergence of natural NA gene variations whose impact on viral fitness and NA inhibitor susceptibility are poorly defined. We generated seven genetically stable recombinant clade 2.2 A/Turkey/15/06-like (H5N1 influenza viruses carrying NA mutations located either in the framework residues (E119A, H274Y, N294S or in close proximity to the NA enzyme active site (V116A, I117V, K150N, Y252H. NA enzyme inhibition assays showed that NA mutations at positions 116, 117, 274, and 294 reduced susceptibility to oseltamivir carboxylate (IC(50s increased 5- to 940-fold. Importantly, the E119A NA mutation (previously reported to confer resistance in the N2 NA subtype was stable in the clade 2.2 H5N1 virus background and induced cross-resistance to oseltamivir carboxylate and zanamivir. We demonstrated that Y252H NA mutation contributed for decreased susceptibility of clade 2.2 H5N1 viruses to oseltamivir carboxylate as compared to clade 1 viruses. The enzyme kinetic parameters (V(max, K(m and K(i of the avian-like N1 NA glycoproteins were highly consistent with their IC(50 values. None of the recombinant H5N1 viruses had attenuated virulence in ferrets inoculated with 10(6 EID(50 dose. Most infected ferrets showed mild clinical disease signs that differed in duration. However, H5N1 viruses carrying the E119A or the N294S NA mutation were lethal to 1 of 3 inoculated animals and were associated with significantly higher virus titers (P<0.01 and inflammation in the lungs compared to the wild-type virus. Our results suggest that highly pathogenic H5N1 variants carrying mutations within the NA active site that decrease susceptibility to NA inhibitors may possess increased

  8. Experimental infection of clade 1.1.2 (H5N1), clade 2.3.2.1c (H5N1) and clade 2.3.4.4 (H5N6) highly pathogenic avian influenza viruses in dogs.

    Science.gov (United States)

    Lyoo, K S; Na, W; Phan, L V; Yoon, S W; Yeom, M; Song, D; Jeong, D G

    2017-12-01

    Since the emergence of highly pathogenic avian influenza (HPAI) H5N1 in Asia, the haemagglutinin (HA) gene of this virus lineage has continued to evolve in avian populations, and H5N1 lineage viruses now circulate concurrently worldwide. Dogs may act as an intermediate host, increasing the potential for zoonotic transmission of influenza viruses. Virus transmission and pathologic changes in HPAI clade 1.1.2 (H5N1)-, 2.3.2.1c (H5N1)- and 2.3.4.4 (H5N6)-infected dogs were investigated. Mild respiratory signs and antibody response were shown in dogs intranasally infected with the viruses. Lung histopathology showed lesions that were associated with moderate interstitial pneumonia in the infected dogs. In this study, HPAI H5N6 virus replication in dogs was demonstrated for the first time. Dogs have been suspected as a "mixing vessel" for reassortments between avian and human influenza viruses to occur. The replication of these three subtypes of the H5 lineage of HPAI viruses in dogs suggests that dogs could serve as intermediate hosts for avian-human influenza virus reassortment if they are also co-infected with human influenza viruses. © 2017 Blackwell Verlag GmbH.

  9. Revision of the Middle American clade of the ant genus Stenamma Westwood (Hymenoptera, Formicidae, Myrmicinae

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    Michael Branstetter

    2013-04-01

    Full Text Available Stenamma is a cryptic “leaf-litter” ant genus that occurs in mesic forest habitats throughout the Holarctic region, Central America, and part of northwestern South America (Colombia and Ecuador. The genus was thought to be restricted primarily to the temperate zone, but recent collecting efforts have uncovered a large radiation of Neotropical forms, which rival the Holarctic species in terms of morphological and behavioral diversity. By inferring a broad-scale molecular phylogeny of Stenamma, Branstetter (2012 showed that all Neotropical species belong to a diverse Middle American clade (MAC, and that this clade is sister to an almost completely geographically separated Holarctic clade (HOC. Here, the Middle American clade of Stenamma is revised to recognize 40 species, of which 33 are described as new. Included in the revision are a key to species based on the worker caste, and for each species where possible, descriptions and images of workers and queens, images of males, information on geographic distribution, descriptions of intraspecific variation, and notes on natural history. Several species groups are defined, but the majority of species remain unassigned due to a lack of diagnostic morphological character states for most molecular clades. The following species are redescribed: S. alas Longino, S. diversum Mann, S. expolitum Smith, S. felixi Mann, S. huachucanum Smith, S. manni Wheeler, and S. schmidti Menozzi. The following are described as new: S. andersoni sp. n., S. atribellum sp. n., S. brujita sp. n., S. callipygium sp. n., S. catracho sp. n., S. connectum sp. n., S. crypticum sp. n., S. cusuco sp. n., S. excisum sp. n., S. expolitico sp. n., S. hojarasca sp. n., S. ignotum sp. n., S. lagunum sp. n., S. llama sp. n., S. leptospinum sp. n., S. lobinodus sp. n., S. longinoi sp. n., S. maximon sp. n., S. megamanni sp. n., S. monstrosum sp. n., S. muralla sp. n., S. nanozoi sp. n., S. nonotch sp. n., S. ochrocnemis sp. n., S

  10. Identification of ochratoxin A producing Aspergillus carbonarius and A. niger clade isolated from grapes using the loop-mediated isothermal amplification (LAMP) reaction.

    Science.gov (United States)

    Storari, M; von Rohr, R; Pertot, I; Gessler, C; Broggini, G A L

    2013-04-01

    To develop two assays based on the loop-mediated isothermal amplification (LAMP) of DNA for the quick and specific identification of Aspergillus carbonarius and ochratoxigenic strains of the Aspergillus niger clade isolated from grapes. Two sets of primers were designed based on the polyketide synthase genes involved or putatively involved in ochratoxin A (OTA) biosynthesis in A. carbonarius and A. niger clade. Hydroxynaphthol blue was used as indirect method to indicate DNA amplification. The limit of detection of both assays was comparable to that of a PCR reaction. Specificities of the reactions were tested using DNA from different black aspergilli isolated from grapes. The two LAMP assays were then used to identify A. carbonarius and ochratoxigenic A. niger and A. awamori grown in pure cultures without a prior DNA extraction. The two LAMP assays permitted to quickly and specifically identify DNA from OTA-producing black aspergilli, as well as isolates grown in pure culture. Monitoring vineyards for the presence of OTA-producing strains is part of the measures to minimize the occurrence of OTA in grape products. The two LAMP assays developed here could be potentially used to speed the screening process of vineyards for the presence of OTA-producing black aspergilli. © 2013 The Society for Applied Microbiology.

  11. Characterisation of a highly pathogenic H5N1 clade 2.3.2 influenza virus isolated from swans in Shanghai, China.

    Science.gov (United States)

    Zhao, Guo; Zhong, Lei; Lu, Xinlun; Hu, Jiao; Gu, Xiaobing; Kai, Yan; Song, Qingqing; Sun, Qing; Liu, Jinbao; Peng, Daxin; Wang, Xiaoquan; Liu, Xiaowen; Liu, Xiufan

    2012-02-01

    In spring 2009, one strain of H5N1 clade 2.3.2 virus was isolated from wild swans in Shanghai, indicating the importance of the wild swan in the ecology of this highly pathogenic avian influenza virus (HPAIV) in Eastern China. Pathogenicity experiments conducted in this study indicated that the virus was highly pathogenic for chickens but lowly pathogenic for mammalian hosts, as evidenced by reduced infection of mice. The analysis of complete genome sequences and genetic evolution showed that A/Swan/Shanghai/10/09 (SW/SH/09) may be derived from the strain A/silky chicken/Shantou/475/2004 (CK/ST/04), which is homologous to the influenza viruses isolated from chicken, duck, pika, little egret, swan, mandarin duck and bar-headed goose in China Hunan, China Qinghai, Mongolia, Russia, Japan, Korea, Laos and Hong Kong during 2007-2011, indicating that the virus has retro-infected diverse wild birds from chicken, and significant spread of the virus is still ongoing through overlapping migratory flyways. On the basis of the molecular analysis, we also found that there was a deletion of the glycosylation site (NSS) in amino acid 156 of the hemagglutinin (HA) protein when compared with that of the other Clade 2.3.2 viruses isolated between 2007 and 2011. More importantly, the sequence analysis of SW/SH/09 virus displayed the drug-resistant mutations on the matrix protein (M2) and neuraminidase (NA) genes.

  12. HFB7 - A novel orphan hydrophobin of the Harzianum and Virens clades of Trichoderma, is involved in response to biotic and abiotic stresses.

    Science.gov (United States)

    Przylucka, Agnes; Akcapinar, Gunseli Bayram; Chenthamara, Komal; Cai, Feng; Grujic, Marica; Karpenko, Juriy; Livoi, Miriam; Shen, Qirong; Kubicek, Christian P; Druzhinina, Irina S

    2017-05-01

    Hydrophobins are small secreted cysteine-rich proteins exclusively found in fungi. They are able to self-assemble in single molecular layers at hydrophobic-hydrophilic interfaces and can therefore be directly involved in establishment of fungi in their habitat. The genomes of filamentous mycotrophic fungi Trichoderma encode a rich diversity of hydrophobins, which are divided in several groups based on their structure and evolution. Here we describe a new member of class II hydrophobins, HFB7, that has a taxonomically restricted occurrence in Harzianum and Virens clades of Trichoderma. Evolutionary analysis reveals that HFB7 proteins form a separate clade distinct from other Trichoderma class II hydrophobins and that genes encoding them evolve under positive selection pressure. Homology modelling of HFB7 structure in comparison to T. reesei HFB2 reveals that the two large hydrophobic patches on the surface of the protein are remarkably conserved between the two hydrophobins despite significant difference in their primary structures. Expression of hfb7 gene in T. virens increases at interactions with other fungi and a plant and in response to a diversity of abiotic stress conditions, and is also upregulated during formation of aerial mycelium in a standing liquid culture. This upregulation significantly exceeds that of expression of hfb7 under a strong constitutive promoter, and T. virens strains overexpressing hfb7 thus display only changes in traits characterized by low hfb7 expression, i.e. faster growth in submerged liquid culture. The hfb7 gene is not expressed in conidia. Our data allow to conclude that this protein is involved in defence of Trichoderma against a diversity of stress factors related to the oxidative stress. Moreover, HFB7 likely helps in the establishment of the fungus in wetlands or other conditions related to high humidity. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Exposure to static magnetic field stimulates quorum sensing circuit in luminescent Vibrio strains of the Harveyi clade.

    Directory of Open Access Journals (Sweden)

    Adelfia Talà

    Full Text Available In this study, the evidence of electron-dense magnetic inclusions with polyhedral shape in the cytoplasm of Harveyi clade Vibrio strain PS1, a bioluminescent bacterium living in symbiosis with marine organisms, led us to investigate the behavior of this bacterium under exposure to static magnetic fields ranging between 20 and 2000 Gauss. When compared to sham-exposed, the light emission of magnetic field-exposed bacteria growing on solid medium at 18°C ±0.1°C was increased up to two-fold as a function of dose and growth phase. Stimulation of bioluminescence by magnetic field was more pronounced during the post-exponential growth and stationary phase, and was lost when bacteria were grown in the presence of the iron chelator deferoxamine, which caused disassembly of the magnetic inclusions suggesting their involvement in magnetic response. As in luminescent Vibrio spp. bioluminescence is regulated by quorum sensing, possible effects of magnetic field exposure on quorum sensing were investigated. Measurement of mRNA levels by reverse transcriptase real time-PCR demonstrated that luxR regulatory gene and luxCDABE operon coding for luciferase and fatty acid reductase complex were significantly up-regulated in magnetic field-exposed bacteria. In contrast, genes coding for a type III secretion system, whose expression was negatively affected by LuxR, were down-regulated. Up-regulation of luxR paralleled with down-regulation of small RNAs that mediate destabilization of luxR mRNA in quorum sensing signaling pathways. The results of experiments with the well-studied Vibrio campbellii strain BB120 (originally classified as Vibrio harveyi and derivative mutants unable to synthesize autoinducers suggest that the effects of magnetic fields on quorum sensing may be mediated by AI-2, the interspecies quorum sensing signal molecule.

  14. Functional analyses of cellulose synthase genes in flax (Linum usitatissimum) by virus-induced gene silencing.

    Science.gov (United States)

    Chantreau, Maxime; Chabbert, Brigitte; Billiard, Sylvain; Hawkins, Simon; Neutelings, Godfrey

    2015-12-01

    Flax (Linum usitatissimum) bast fibres are located in the stem cortex where they play an important role in mechanical support. They contain high amounts of cellulose and so are used for linen textiles and in the composite industry. In this study, we screened the annotated flax genome and identified 14 distinct cellulose synthase (CESA) genes using orthologous sequences previously identified. Transcriptomics of 'primary cell wall' and 'secondary cell wall' flax CESA genes showed that some were preferentially expressed in different organs and stem tissues providing clues as to their biological role(s) in planta. The development for the first time in flax of a virus-induced gene silencing (VIGS) approach was used to functionally evaluate the biological role of different CESA genes in stem tissues. Quantification of transcript accumulation showed that in many cases, silencing not only affected targeted CESA clades, but also had an impact on other CESA genes. Whatever the targeted clade, inactivation by VIGS affected plant growth. In contrast, only clade 1- and clade 6-targeted plants showed modifications in outer-stem tissue organization and secondary cell wall formation. In these plants, bast fibre number and structure were severely impacted, suggesting that the targeted genes may play an important role in the establishment of the fibre cell wall. Our results provide new fundamental information about cellulose biosynthesis in flax that should facilitate future plant improvement/engineering. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  15. Divergence and Conservative Evolution of XTNX Genes in Land Plants

    Directory of Open Access Journals (Sweden)

    Yan-Mei Zhang

    2017-10-01

    Full Text Available The Toll-interleukin-1 receptor (TIR and Nucleotide-binding site (NBS domains are two major components of the TIR-NBS-leucine-rich repeat family plant disease resistance genes. Extensive functional and evolutionary studies have been performed on these genes; however, the characterization of a small group of genes that are composed of atypical TIR and NBS domains, namely XTNX genes, is limited. The present study investigated this specific gene family by conducting genome-wide analyses of 59 green plant genomes. A total of 143 XTNX genes were identified in 51 of the 52 land plant genomes, whereas no XTNX gene was detected in any green algae genomes, which indicated that XTNX genes originated upon emergence of land plants. Phylogenetic analysis revealed that the ancestral XTNX gene underwent two rounds of ancient duplications in land plants, which resulted in the formation of clades I/II and clades IIa/IIb successively. Although clades I and IIb have evolved conservatively in angiosperms, the motif composition difference and sequence divergence at the amino acid level suggest that functional divergence may have occurred since the separation of the two clades. In contrast, several features of the clade IIa genes, including the absence in the majority of dicots, the long branches in the tree, the frequent loss of ancestral motifs, and the loss of expression in all detected tissues of Zea mays, all suggest that the genes in this lineage might have undergone pseudogenization. This study highlights that XTNX genes are a gene family originated anciently in land plants and underwent specific conservative pattern in evolution.

  16. Morphological features of the species of the genus Chlamydomonas s.l. (Chlorophyta from various molecular clades

    Directory of Open Access Journals (Sweden)

    Maria N. Pavlovska

    2012-03-01

    Full Text Available The morphology of 78 authentic strains from 5 clades into culture condition was investigated. The complex of phenotype features was established. Such features as: type of mucilage and their origin, mucilage collapse under methylene blue, saving papilla and stigma in not motile stage, extracellular matrix formation inside cell wall, the way of sporangium break, pyrenoid and stigma habit before cell division, cell shape, chloroplast morphology. Diagnostic features for determination of taxa on clades level are discussed.

  17. Origin and Population Dynamics of a Novel HIV-1 Subtype G Clade Circulating in Cape Verde and Portugal.

    Science.gov (United States)

    de Pina-Araujo, Isabel Inês M; Delatorre, Edson; Guimarães, Monick L; Morgado, Mariza G; Bello, Gonzalo

    2015-01-01

    The human immunodeficiency virus type 1 (HIV-1) subtype G is the most prevalent and second most prevalent HIV-1 clade in Cape Verde and Portugal, respectively; but there is no information about the origin and spatiotemporal dispersal pattern of this HIV-1 clade circulating in those countries. To this end, we used Maximum Likelihood and Bayesian coalescent-based methods to analyze a collection of 578 HIV-1 subtype G pol sequences sampled throughout Portugal, Cape Verde and 11 other countries from West and Central Africa over a period of 22 years (1992 to 2013). Our analyses indicate that most subtype G sequences from Cape Verde (80%) and Portugal (95%) branched together in a distinct monophyletic cluster (here called G(CV-PT)). The G(CV-PT) clade probably emerged after a single migration of the virus out of Central Africa into Cape Verde between the late 1970s and the middle 1980s, followed by a rapid dissemination to Portugal a couple of years later. Reconstruction of the demographic history of the G(CV-PT) clade circulating in Cape Verde and Portugal indicates that this viral clade displayed an initial phase of exponential growth during the 1980s and 1990s, followed by a decline in growth rate since the early 2000s. Our data also indicate that during the exponential growth phase the G(CV-PT) clade recombined with a preexisting subtype B viral strain circulating in Portugal, originating the CRF14_BG clade that was later disseminated to Spain and Cape Verde. Historical and recent human population movements between Angola, Cape Verde and Portugal probably played a key role in the origin and dispersal of the G(CV-PT )and CRF14_BG clades.

  18. Characterization of humoral responses to soluble trimeric HIV gp140 from a clade A Ugandan field isolate.

    Science.gov (United States)

    Visciano, Maria Luisa; Tagliamonte, Maria; Stewart-Jones, Guillaume; Heyndrickx, Leo; Vanham, Guido; Jansson, Marianne; Fomsgaard, Anders; Grevstad, Berit; Ramaswamy, Meghna; Buonaguro, Franco M; Tornesello, Maria Lina; Biswas, Priscilla; Scarlatti, Gabriella; Buonaguro, Luigi

    2013-07-08

    Trimeric soluble forms of HIV gp140 envelope glycoproteins represent one of the closest molecular structures compared to native spikes present on intact virus particles. Trimeric soluble gp140 have been generated by several groups and such molecules have been shown to induce antibodies with neutralizing activity against homologous and heterologous viruses. In the present study, we generated a recombinant trimeric soluble gp140, derived from a previously identified Ugandan A-clade HIV field isolate (gp14094UG018). Antibodies elicited in immunized rabbits show a broad binding pattern to HIV envelopes of different clades. An epitope mapping analysis reveals that, on average, the binding is mostly focused on the C1, C2, V3, V5 and C5 regions. Immune sera show neutralization activity to Tier 1 isolates of different clades, demonstrating cross clade neutralizing activity which needs to be further broadened by possible structural modifications of the clade A gp14094UG018. Our results provide a rationale for the design and evaluation of immunogens and the clade A gp14094UG018 shows promising characteristics for potential involvement in an effective HIV vaccine with broad activity.

  19. Phylogenetic Framework and Molecular Signatures for the Main Clades of the Phylum Actinobacteria

    Science.gov (United States)

    Gao, Beile

    2012-01-01

    Summary: The phylum Actinobacteria harbors many important human pathogens and also provides one of the richest sources of natural products, including numerous antibiotics and other compounds of biotechnological interest. Thus, a reliable phylogeny of this large phylum and the means to accurately identify its different constituent groups are of much interest. Detailed phylogenetic and comparative analyses of >150 actinobacterial genomes reported here form the basis for achieving these objectives. In phylogenetic trees based upon 35 conserved proteins, most of the main groups of Actinobacteria as well as a number of their superageneric clades are resolved. We also describe large numbers of molecular markers consisting of conserved signature indels in protein sequences and whole proteins that are specific for either all Actinobacteria or their different clades (viz., orders, families, genera, and subgenera) at various taxonomic levels. These signatures independently support the existence of different phylogenetic clades, and based upon them, it is now possible to delimit the phylum Actinobacteria (excluding Coriobacteriia) and most of its major groups in clear molecular terms. The species distribution patterns of these markers also provide important information regarding the interrelationships among different main orders of Actinobacteria. The identified molecular markers, in addition to enabling the development of a stable and reliable phylogenetic framework for this phylum, also provide novel and powerful means for the identification of different groups of Actinobacteria in diverse environments. Genetic and biochemical studies on these Actinobacteria-specific markers should lead to the discovery of novel biochemical and/or other properties that are unique to different groups of Actinobacteria. PMID:22390973

  20. Pelagic larval duration predicts extinction risk in a freshwater fish clade.

    Science.gov (United States)

    Douglas, Morgan; Keck, Benjamin P; Ruble, Crystal; Petty, Melissa; Shute, J R; Rakes, Patrick; Hulsey, C Darrin

    2013-01-01

    Pelagic larval duration (PLD) can influence evolutionary processes ranging from dispersal to extinction in aquatic organisms. Using estimates of PLD obtained from species of North American darters (Percidae: Etheostomatinae), we demonstrate that this freshwater fish clade exhibits surprising variation in PLD. Comparative analyses provide some evidence that higher stream gradients favour the evolution of shorter PLD. Additionally, similar to patterns in the marine fossil record in which lower PLD is associated with greater extinction probability, we found a reduced PLD in darter lineages was evolutionarily associated with extinction risk. Understanding the causes and consequences of PLD length could lead to better management and conservation of organisms in our increasingly imperiled aquatic environments.

  1. Contrasting patterns of phylogenetic assemblage structure along the elevational gradient for major hummingbird clades

    DEFF Research Database (Denmark)

    Parra, Juan L.; Rahbek, Carsten; McGuire, Jimmy A.

    2011-01-01

    Aim We evaluated the hypothesis that, given niche conservatism, relatedness of co-occurring hummingbird species of a given clade will increase at greater distances from the elevation where it originated. We also used prior knowledge of flight biomechanics and feeding specialization of hummingbird...... specialization (hermits and brilliants) always included a vegetation-related variable as an important predictor of change in phylogenetic structure. Main conclusions We found no overall support for the conservatism and zone of origin hypotheses. Knowledge of each clade’s natural history proved useful...

  2. Phylogenomic analyses and molecular signatures for the class Halobacteria and its two major clades: a proposal for division of the class Halobacteria into an emended order Halobacteriales and two new orders, Haloferacales ord. nov. and Natrialbales ord. nov., containing the novel families Haloferacaceae fam. nov. and Natrialbaceae fam. nov.

    Science.gov (United States)

    Gupta, Radhey S; Naushad, Sohail; Baker, Sheridan

    2015-03-01

    The Halobacteria constitute one of the largest groups within the Archaea. The hierarchical relationship among members of this large class, which comprises a single order and a single family, has proven difficult to determine based upon 16S rRNA gene trees and morphological and physiological characteristics. This work reports detailed phylogenetic and comparative genomic studies on >100 halobacterial (haloarchaeal) genomes containing representatives from 30 genera to investigate their evolutionary relationships. In phylogenetic trees reconstructed on the basis of 32 conserved proteins, using both neighbour-joining and maximum-likelihood methods, two major clades (clades A and B) encompassing nearly two-thirds of the sequenced haloarchaeal species were strongly supported. Clades grouping the same species/genera were also supported by the 16S rRNA gene trees and trees for several individual highly conserved proteins (RpoC, EF-Tu, UvrD, GyrA, EF-2/EF-G). In parallel, our comparative analyses of protein sequences from haloarchaeal genomes have identified numerous discrete molecular markers in the form of conserved signature indels (CSI) in protein sequences and conserved signature proteins (CSPs) that are found uniquely in specific groups of haloarchaea. Thirteen CSIs in proteins involved in diverse functions and 68 CSPs that are uniquely present in all or most genome-sequenced haloarchaea provide novel molecular means for distinguishing members of the class Halobacteria from all other prokaryotes. The members of clade A are distinguished from all other haloarchaea by the unique shared presence of two CSIs in the ribose operon protein and small GTP-binding protein and eight CSPs that are found specifically in members of this clade. Likewise, four CSIs in different proteins and five other CSPs are present uniquely in members of clade B and distinguish them from all other haloarchaea. Based upon their specific clustering in phylogenetic trees for different gene

  3. Single acquisition of protelomerase gave rise to speciation of a large and diverse clade within the Agrobacterium/Rhizobium supercluster characterized by the presence of a linear chromid.

    Science.gov (United States)

    Ramírez-Bahena, Martha H; Vial, Ludovic; Lassalle, Florent; Diel, Benjamin; Chapulliot, David; Daubin, Vincent; Nesme, Xavier; Muller, Daniel

    2014-04-01

    Linear chromosomes are atypical in bacteria and likely a secondary trait derived from ancestral circular molecules. Within the Rhizobiaceae family, whose genome contains at least two chromosomes, a particularity of Agrobacterium fabrum (formerly A. tumefaciens) secondary chromosome (chromid) is to be linear and hairpin-ended thanks to the TelA protelomerase. Linear topology and telA distributions within this bacterial family was screened by pulse field gel electrophoresis and PCR. In A. rubi, A. larrymoorei, Rhizobium skierniewicense, A. viscosum, Agrobacterium sp. NCPPB 1650, and every genomospecies of the biovar 1/A. tumefaciens species complex (including R. pusense, A. radiobacter, A. fabrum, R. nepotum plus seven other unnamed genomospecies), linear chromid topologies were retrieved concomitantly with telA presence, whereas the remote species A. vitis, Allorhizobium undicola, Rhizobium rhizogenes and Ensifer meliloti harbored a circular chromid as well as no telA gene. Moreover, the telA phylogeny is congruent with that of recA used as a marker gene of the Agrobacterium phylogeny. Collectively, these findings strongly suggest that single acquisition of telA by an ancestor was the founding event of a large and diverse clade characterized by the presence of a linear chromid. This clade, characterized by unusual genome architecture, appears to be a relevant candidate to serve as a basis for a possible redefinition of the controversial Agrobacterium genus. In this respect, investigating telA in sequenced genomes allows to both ascertain the place of concerned strains into Agrobacterium spp. and their actual assignation to species/genomospecies in this genus. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Phylogenetically distant clade of Nostoc-like taxa with the description of Aliinostoc gen. nov. and Aliinostoc morphoplasticum sp. nov.

    Science.gov (United States)

    Bagchi, Suvendra Nath; Dubey, Neelam; Singh, Prashant

    2017-09-01

    Nostoc is a complex and tough genus to differentiate, and its morphological plasticity makes it taxonomically complicated. Its cryptic diversity and almost no distinguishable morphological characteristics make this genus incredibly heterogeneous to evaluate on taxonomic scales. The strain NOS, isolated from a eutrophic water body, is being described as a new genus Aliinostoc with the strain showing motile hormogonia with gas vesicles as an atypical feature, which is currently considered as the diacritical feature of the genus but should be subjected to critical evaluation in the near future. The phylogenetic placement of Aliinostoc along with some other related sequences of Nostoc clearly separated this clade from Nostoc sensu stricto with high bootstrap support and robust topology in all the methods tested, thus providing strong proof of the taxa being representative of a new genus which morphologically appears to be Nostoc-like. Subsequent phylogenetic assessment using the rbcL, psbA, rpoC1 and tufA genes was done with the aim of facilitating future multi-locus studies on the proposed genus for better taxonomic clarity and resolution. Folding of the 16S-23S internal transcribed spacer region and subsequent comparisons with members of the genera Nostoc, Anabaena, Aulosira, Cylindrospermum, Sphaerospermopsis, Raphidiopsis, Desmonostoc and Mojavia gave entirely new secondary structures for the D1-D1' and box-B helix. Clear and separate clustering from Nostoc sensu stricto supports the establishment of Aliinostoc gen. nov. with the type species being Aliinostoc morphoplasticum sp. nov. in accordance with the International Code of Nomenclature for algae, fungi and plants.

  5. Skull ontogeny: developmental patterns of fishes conserved across major tetrapod clades.

    Science.gov (United States)

    Schoch, Rainer R

    2006-01-01

    In vertebrates, the ontogeny of the bony skull forms a particularly complex part of embryonic development. Although this area used to be restricted to neontology, recent discoveries of fossil ontogenies provide an additional source of data. One of the most detailed ossification sequences is known from Permo-Carboniferous amphibians, the branchiosaurids. These temnospondyls form a near-perfect link between the piscine osteichthyans and the various clades of extant tetrapods, retaining a full complement of dermal bones in the skull. For the first time, the broader evolutionary significance of these event sequences is analyzed, focusing on the identification of sequence heterochronies. A set of 120 event pairs was analyzed by event pair cracking, which helped identify active movers. A cladistic analysis of the event pair data was also carried out, highlighting some shared patterns between widely divergent clades of tetrapods. The analyses revealed an unexpected degree of similarity between the widely divergent taxa. Most interesting is the apparently modular composition of the cranial sequence: five clusters of bones were discovered in each of which the elements form in the same time window: (1) jaw bones, (2) marginal palatal elements, (3) circumorbital bones, (4) skull roof elements, and (5) neurocranial ossifications. In the studied taxa, these "modules" have in most cases been shifted fore and back on the trajectory relative to the Amia sequence, but did not disintegrate. Such "modules" might indicate a high degree of evolutionary limitation (constraint).

  6. Phylogeographic Patterns in Africa and High Resolution Delineation of Genetic Clades in the Lion (Panthera leo)

    Science.gov (United States)

    Bertola, L. D.; Jongbloed, H.; van der Gaag, K. J.; de Knijff, P.; Yamaguchi, N.; Hooghiemstra, H.; Bauer, H.; Henschel, P.; White, P. A.; Driscoll, C. A.; Tende, T.; Ottosson, U.; Saidu, Y.; Vrieling, K.; de Iongh, H. H.

    2016-08-01

    Comparative phylogeography of African savannah mammals shows a congruent pattern in which populations in West/Central Africa are distinct from populations in East/Southern Africa. However, for the lion, all African populations are currently classified as a single subspecies (Panthera leo leo), while the only remaining population in Asia is considered to be distinct (Panthera leo persica). This distinction is disputed both by morphological and genetic data. In this study we introduce the lion as a model for African phylogeography. Analyses of mtDNA sequences reveal six supported clades and a strongly supported ancestral dichotomy with northern populations (West Africa, Central Africa, North Africa/Asia) on one branch, and southern populations (North East Africa, East/Southern Africa and South West Africa) on the other. We review taxonomies and phylogenies of other large savannah mammals, illustrating that similar clades are found in other species. The described phylogeographic pattern is considered in relation to large scale environmental changes in Africa over the past 300,000 years, attributable to climate. Refugial areas, predicted by climate envelope models, further confirm the observed pattern. We support the revision of current lion taxonomy, as recognition of a northern and a southern subspecies is more parsimonious with the evolutionary history of the lion.

  7. Evolutionary history of LINE-1 in the major clades of placental mammals.

    Directory of Open Access Journals (Sweden)

    Paul D Waters

    2007-01-01

    Full Text Available LINE-1 constitutes an important component of mammalian genomes. It has a dynamic evolutionary history characterized by the rise, fall and replacement of subfamilies. Most data concerning LINE-1 biology and evolution are derived from the human and mouse genomes and are often assumed to hold for all placentals.To examine LINE-1 relationships, sequences from the 3' region of the reverse transcriptase from 21 species (representing 13 orders across Afrotheria, Xenarthra, Supraprimates and Laurasiatheria were obtained from whole genome sequence assemblies, or by PCR with degenerate primers. These sequences were aligned and analysed.Our analysis reflects accepted placental relationships suggesting mostly lineage-specific LINE-1 families. The data provide clear support for several clades including Glires, Supraprimates, Laurasiatheria, Boreoeutheria, Xenarthra and Afrotheria. Within the afrotherian LINE-1 (AfroLINE clade, our tree supports Paenungulata, Afroinsectivora and Afroinsectiphillia. Xenarthran LINE-1 (XenaLINE falls sister to AfroLINE, providing some support for the Atlantogenata (Xenarthra+Afrotheria hypothesis.LINEs and SINEs make up approximately half of all placental genomes, so understanding their dynamics is an essential aspect of comparative genomics. Importantly, a tree of LINE-1 offers a different view of the root, as long edges (branches such as that to marsupials are shortened and/or broken up. Additionally, a robust phylogeny of diverse LINE-1 is essential in testing that site-specific LINE-1 insertions, often regarded as homoplasy-free phylogenetic markers, are indeed unique and not convergent.

  8. Phylogeographic Patterns in Africa and High Resolution Delineation of Genetic Clades in the Lion (Panthera leo).

    Science.gov (United States)

    Bertola, L D; Jongbloed, H; van der Gaag, K J; de Knijff, P; Yamaguchi, N; Hooghiemstra, H; Bauer, H; Henschel, P; White, P A; Driscoll, C A; Tende, T; Ottosson, U; Saidu, Y; Vrieling, K; de Iongh, H H

    2016-08-04

    Comparative phylogeography of African savannah mammals shows a congruent pattern in which populations in West/Central Africa are distinct from populations in East/Southern Africa. However, for the lion, all African populations are currently classified as a single subspecies (Panthera leo leo), while the only remaining population in Asia is considered to be distinct (Panthera leo persica). This distinction is disputed both by morphological and genetic data. In this study we introduce the lion as a model for African phylogeography. Analyses of mtDNA sequences reveal six supported clades and a strongly supported ancestral dichotomy with northern populations (West Africa, Central Africa, North Africa/Asia) on one branch, and southern populations (North East Africa, East/Southern Africa and South West Africa) on the other. We review taxonomies and phylogenies of other large savannah mammals, illustrating that similar clades are found in other species. The described phylogeographic pattern is considered in relation to large scale environmental changes in Africa over the past 300,000 years, attributable to climate. Refugial areas, predicted by climate envelope models, further confirm the observed pattern. We support the revision of current lion taxonomy, as recognition of a northern and a southern subspecies is more parsimonious with the evolutionary history of the lion.

  9. Cryptosporidium,Giardia, Cryptococcus, Pneumocystis genetic variability: cryptic biological species or clonal near-clades?

    Directory of Open Access Journals (Sweden)

    Michel Tibayrenc

    2014-04-01

    Full Text Available An abundant literature dealing with the population genetics and taxonomy of Giardia duodenalis, Cryptosporidium spp., Pneumocystis spp., and Cryptococcus spp., pathogens of high medical and veterinary relevance, has been produced in recent years. We have analyzed these data in the light of new population genetic concepts dealing with predominant clonal evolution (PCE recently proposed by us. In spite of the considerable phylogenetic diversity that exists among these pathogens, we have found striking similarities among them. The two main PCE features described by us, namely highly significant linkage disequilibrium and near-clading (stable phylogenetic clustering clouded by occasional recombination, are clearly observed in Cryptococcus and Giardia, and more limited indication of them is also present in Cryptosporidium and Pneumocystis. Moreover, in several cases, these features still obtain when the near-clades that subdivide the species are analyzed separately ("Russian doll pattern". Lastly, several sets of data undermine the notion that certain microbes form clonal lineages simply owing to a lack of opportunity to outcross due to low transmission rates leading to lack of multiclonal infections ("starving sex hypothesis". We propose that the divergent taxonomic and population genetic inferences advanced by various authors about these pathogens may not correspond to true evolutionary differences and could be, rather, the reflection of idiosyncratic practices among compartmentalized scientific communities. The PCE model provides an opportunity to revise the taxonomy and applied research dealing with these pathogens and others, such as viruses, bacteria, parasitic protozoa, and fungi.

  10. Preliminary phylogenetic analysis of the Andean clade and the placement of new Colombian blueberries (Ericaceae, Vaccinieae

    Directory of Open Access Journals (Sweden)

    Paola Pedraza-Penalosa

    2015-04-01

    Full Text Available The blueberry tribe Vaccinieae (Ericaceae is particularly diverse in South America and underwent extensive radiation in Colombia where many endemics occur. Recent fieldwork in Colombia has resulted in valuable additions to the phylogeny and as well in the discovery of morphologically noteworthy new species that need to be phylogenetically placed before being named. This is particularly important, as the monophyly of many of the studied genera have not been confirmed. In order to advance our understanding of the relationships within neotropical Vaccinieae and advice the taxonomy of the new blueberry relatives, here we present the most comprehensive phylogenetic analysis for the Andean clade. Anthopterus, Demosthenesia, and Pellegrinia are among the putative Andean genera recovered as monophyletic, while other eight Andean genera were not. The analyses also showed that genera that have been traditionally widely defined are non-monophyletic and could be further split into more discrete groups. Four newly discovered Colombian Vaccinieae are placed in the monophyletic Satyria s.s. and the Psammisia I clade. Although these new species are endemic to the Colombian Western Cordillera and Chocó biogeographic region and three are not known outside of Las Orquídeas National Park, they do not form sister pairs.

  11. Culture and hybridization experiments on an ulva clade including the Qingdao strain blooming in the yellow sea.

    Directory of Open Access Journals (Sweden)

    Masanori Hiraoka

    2011-05-01

    Full Text Available In the summer of 2008, immediately prior to the Beijing Olympics, a massive green tide of the genus Ulva covered the Qingdao coast of the Yellow Sea in China. Based on molecular analyses using the nuclear encoded rDNA internal transcribed spacer (ITS region, the Qingdao strains dominating the green tide were reported to be included in a single phylogenetic clade, currently regarded as a single species. On the other hand, our detailed phylogenetic analyses of the clade, using a higher resolution DNA marker, suggested that two genetically separate entities could be included within the clade. However, speciation within the Ulva clade has not yet been examined. We examined the occurrence of an intricate speciation within the clade, including the Qingdao strains, via combined studies of culture, hybridization and phylogenetic analysis. The two entities separated by our phylogenetic analyses of the clade were simply distinguished as U. linza and U. prolifera morphologically by the absence or presence of branches in cultured thalli. The inclusion of sexual strains and several asexual strains were found in each taxon. Hybridizations among the sexual strains also supported the separation by a partial gamete incompatibility. The sexually reproducing Qingdao strains crossed with U. prolifera without any reproductive boundary, but a complete reproductive isolation to U. linza occurred by gamete incompatibility. The results demonstrate that the U. prolifera group includes two types of sexual strains distinguishable by crossing affinity to U. linza. Species identification within the Ulva clade requires high resolution DNA markers and/or hybridization experiments and is not possible by reliance on the ITS markers alone.

  12. Culture and Hybridization Experiments on an Ulva Clade Including the Qingdao Strain Blooming in the Yellow Sea

    Science.gov (United States)

    Hiraoka, Masanori; Ichihara, Kensuke; Zhu, Wenrong; Ma, Jiahai; Shimada, Satoshi

    2011-01-01

    In the summer of 2008, immediately prior to the Beijing Olympics, a massive green tide of the genus Ulva covered the Qingdao coast of the Yellow Sea in China. Based on molecular analyses using the nuclear encoded rDNA internal transcribed spacer (ITS) region, the Qingdao strains dominating the green tide were reported to be included in a single phylogenetic clade, currently regarded as a single species. On the other hand, our detailed phylogenetic analyses of the clade, using a higher resolution DNA marker, suggested that two genetically separate entities could be included within the clade. However, speciation within the Ulva clade has not yet been examined. We examined the occurrence of an intricate speciation within the clade, including the Qingdao strains, via combined studies of culture, hybridization and phylogenetic analysis. The two entities separated by our phylogenetic analyses of the clade were simply distinguished as U. linza and U. prolifera morphologically by the absence or presence of branches in cultured thalli. The inclusion of sexual strains and several asexual strains were found in each taxon. Hybridizations among the sexual strains also supported the separation by a partial gamete incompatibility. The sexually reproducing Qingdao strains crossed with U. prolifera without any reproductive boundary, but a complete reproductive isolation to U. linza occurred by gamete incompatibility. The results demonstrate that the U. prolifera group includes two types of sexual strains distinguishable by crossing affinity to U. linza. Species identification within the Ulva clade requires high resolution DNA markers and/or hybridization experiments and is not possible by reliance on the ITS markers alone. PMID:21573216

  13. MVA-based H5N1 vaccine affords cross-clade protection in mice against influenza A/H5N1 viruses at low doses and after single immunization.

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    Joost H C M Kreijtz

    Full Text Available Human infections with highly pathogenic avian influenza viruses of the H5N1 subtype, frequently reported since 2003, result in high morbidity and mortality. It is feared that these viruses become pandemic, therefore the development of safe and effective vaccines is desirable. MVA-based H5N1 vaccines already proved to be effective when two immunizations with high doses were used. Dose-sparing strategies would increase the number of people that can be vaccinated when the amount of vaccine preparations that can be produced is limited. Furthermore, protective immunity is induced ideally after a single immunization. Therefore the minimal requirements for induction of protective immunity with a MVA-based H5N1 vaccine were assessed in mice. To this end, mice were vaccinated once or twice with descending doses of a recombinant MVA expressing the HA gene of influenza virus A/Vietnam/1194/04. The protective efficacy was determined after challenge infection with the homologous clade 1 virus and a heterologous virus derived from clade 2.1, A/Indonesia/5/05 by assessing weight loss, virus replication and histopathological changes. It was concluded that MVA-based vaccines allowed significant dose-sparing and afford cross-clade protection, also after a single immunization, which are favorable properties for an H5N1 vaccine candidate.

  14. Advanced Microbial Taxonomy Combined with Genome-Based-Approaches Reveals that Vibrio astriarenae sp. nov., an Agarolytic Marine Bacterium, Forms a New Clade in Vibrionaceae.

    Science.gov (United States)

    Al-Saari, Nurhidayu; Gao, Feng; Rohul, Amin A K M; Sato, Kazumichi; Sato, Keisuke; Mino, Sayaka; Suda, Wataru; Oshima, Kenshiro; Hattori, Masahira; Ohkuma, Moriya; Meirelles, Pedro M; Thompson, Fabiano L; Thompson, Cristiane; Filho, Gilberto M A; Gomez-Gil, Bruno; Sawabe, Toko; Sawabe, Tomoo

    2015-01-01

    Advances in genomic microbial taxonomy have opened the way to create a more universal and transparent concept of species but is still in a transitional stage towards becoming a defining robust criteria for describing new microbial species with minimum features obtained using both genome and classical polyphasic taxonomies. Here we performed advanced microbial taxonomies combined with both genome-based and classical approaches for new agarolytic vibrio isolates to describe not only a novel Vibrio species but also a member of a new Vibrio clade. Two novel vibrio strains (Vibrio astriarenae sp. nov. C7T and C20) showing agarolytic, halophilic and fermentative metabolic activity were isolated from a seawater sample collected in a coral reef in Okinawa. Intraspecific similarities of the isolates were identical in both sequences on the 16S rRNA and pyrH genes, but the closest relatives on the molecular phylogenetic trees on the basis of 16S rRNA and pyrH gene sequences were V. hangzhouensis JCM 15146T (97.8% similarity) and V. agarivorans CECT 5085T (97.3% similarity), respectively. Further multilocus sequence analysis (MLSA) on the basis of 8 protein coding genes (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA, and topA) obtained by the genome sequences clearly showed the V. astriarenae strain C7T and C20 formed a distinct new clade protruded next to V. agarivorans CECT 5085T. The singleton V. agarivorans has never been included in previous MLSA of Vibrionaceae due to the lack of some gene sequences. Now the gene sequences are completed and analysis of 100 taxa in total provided a clear picture describing the association of V. agarivorans into pre-existing concatenated network tree and concluded its relationship to our vibrio strains. Experimental DNA-DNA hybridization (DDH) data showed that the strains C7T and C20 were conspecific but were separated from all of the other Vibrio species related on the basis of both 16S rRNA and pyrH gene phylogenies (e.g., V. agarivorans CECT

  15. Advanced Microbial Taxonomy Combined with Genome-Based-Approaches Reveals that Vibrio astriarenae sp. nov., an Agarolytic Marine Bacterium, Forms a New Clade in Vibrionaceae.

    Directory of Open Access Journals (Sweden)

    Nurhidayu Al-Saari

    Full Text Available Advances in genomic microbial taxonomy have opened the way to create a more universal and transparent concept of species but is still in a transitional stage towards becoming a defining robust criteria for describing new microbial species with minimum features obtained using both genome and classical polyphasic taxonomies. Here we performed advanced microbial taxonomies combined with both genome-based and classical approaches for new agarolytic vibrio isolates to describe not only a novel Vibrio species but also a member of a new Vibrio clade. Two novel vibrio strains (Vibrio astriarenae sp. nov. C7T and C20 showing agarolytic, halophilic and fermentative metabolic activity were isolated from a seawater sample collected in a coral reef in Okinawa. Intraspecific similarities of the isolates were identical in both sequences on the 16S rRNA and pyrH genes, but the closest relatives on the molecular phylogenetic trees on the basis of 16S rRNA and pyrH gene sequences were V. hangzhouensis JCM 15146T (97.8% similarity and V. agarivorans CECT 5085T (97.3% similarity, respectively. Further multilocus sequence analysis (MLSA on the basis of 8 protein coding genes (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA, and topA obtained by the genome sequences clearly showed the V. astriarenae strain C7T and C20 formed a distinct new clade protruded next to V. agarivorans CECT 5085T. The singleton V. agarivorans has never been included in previous MLSA of Vibrionaceae due to the lack of some gene sequences. Now the gene sequences are completed and analysis of 100 taxa in total provided a clear picture describing the association of V. agarivorans into pre-existing concatenated network tree and concluded its relationship to our vibrio strains. Experimental DNA-DNA hybridization (DDH data showed that the strains C7T and C20 were conspecific but were separated from all of the other Vibrio species related on the basis of both 16S rRNA and pyrH gene phylogenies (e.g., V

  16. Transmissibility of the monkeypox virus clades via respiratory transmission: investigation using the prairie dog-monkeypox virus challenge system.

    Directory of Open Access Journals (Sweden)

    Christina L Hutson

    Full Text Available Monkeypox virus (MPXV is endemic within Africa where it sporadically is reported to cause outbreaks of human disease. In 2003, an outbreak of human MPXV occurred in the US after the importation of infected African rodents. Since the eradication of smallpox (caused by an orthopoxvirus (OPXV related to MPXV and cessation of routine smallpox vaccination (with the live OPXV vaccinia, there is an increasing population of people susceptible to OPXV diseases. Previous studies have shown that the prairie dog MPXV model is a functional animal model for the study of systemic human OPXV illness. Studies with this model have demonstrated that infected animals are able to transmit the virus to naive animals through multiple routes of exposure causing subsequent infection, but were not able to prove that infected animals could transmit the virus exclusively via the respiratory route. Herein we used the model system to evaluate the hypothesis that the Congo Basin clade of MPXV is more easily transmitted, via respiratory route, than the West African clade. Using a small number of test animals, we show that transmission of viruses from each of the MPXV clade was minimal via respiratory transmission. However, transmissibility of the Congo Basin clade was slightly greater than West African MXPV clade (16.7% and 0% respectively. Based on these findings, respiratory transmission appears to be less efficient than those of previous studies assessing contact as a mechanism of transmission within the prairie dog MPXV animal model.

  17. Synergistic activity profile of griffithsin in combination with tenofovir, maraviroc and enfuvirtide against HIV-1 clade C

    International Nuclear Information System (INIS)

    Ferir, Geoffrey; Palmer, Kenneth E.; Schols, Dominique

    2011-01-01

    Griffithsin (GRFT) is possibly the most potent anti-HIV peptide found in natural sources. Due to its potent and broad-spectrum antiviral activity and unique safety profile it has great potential as topical microbicide component. Here, we evaluated various combinations of GRFT against HIV-1 clade B and clade C isolates in primary peripheral blood mononuclear cells (PBMCs) and in CD4 + MT-4 cells. In all combinations tested, GRFT showed synergistic activity profile with tenofovir, maraviroc and enfuvirtide based on the median effect principle with combination indices (CI) varying between 0.34 and 0.79 at the calculated EC 95 level. Furthermore, the different glycosylation patterns on the viral envelope of clade B and clade C gp120 had no observable effect on the synergistic interactions. Overall, we can conclude that the evaluated two-drug combination increases their antiviral potency and supports further clinical investigations in pre-exposure prophylaxis for GRFT combinations in the context of HIV-1 clade C infection.

  18. Remarkable phylogenetic resolution of the most complex clade of Cyprinidae (Teleostei: Cypriniformes): a proof of concept of homology assessment and partitioning sequence data integrated with mixed model Bayesian analyses.

    Science.gov (United States)

    Tao, Wenjing; Mayden, Richard L; He, Shunping

    2013-03-01

    Despite many efforts to resolve evolutionary relationships among major clades of Cyprinidae, some nodes have been especially problematic and remain unresolved. In this study, we employ four nuclear gene fragments (3.3kb) to infer interrelationships of the Cyprinidae. A reconstruction of the phylogenetic relationships within the family using maximum parsimony, maximum likelihood, and Bayesian analyses is presented. Among the taxa within the monophyletic Cyprinidae, Rasborinae is the basal-most lineage; Cyprinine is sister to Leuciscine. The monophyly for the subfamilies Gobioninae, Leuciscinae and Acheilognathinae were resolved with high nodal support. Although our results do not completely resolve relationships within Cyprinidae, this study presents novel and significant findings having major implications for a highly diverse and enigmatic clade of East-Asian cyprinids. Within this monophyletic group five closely-related subgroups are identified. Tinca tinca, one of the most phylogenetically enigmatic genera in the family, is strongly supported as having evolutionary affinities with this East-Asian clade; an established yet remarkable association because of the natural variation in phenotypes and generalized ecological niches occupied by these taxa. Our results clearly argue that the choice of partitioning strategies has significant impacts on the phylogenetic reconstructions, especially when multiple genes are being considered. The most highly partitioned model (partitioned by codon positions within genes) extracts the strongest phylogenetic signals and performs better than any other partitioning schemes supported by the strongest 2Δln Bayes factor. Future studies should include higher levels of taxon sampling and partitioned, model-based analyses. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. A novel MADS-box gene subfamily with a sister-group relationship to class B floral homeotic genes.

    Science.gov (United States)

    Becker, A; Kaufmann, K; Freialdenhoven, A; Vincent, C; Li, M-A; Saedler, H; Theissen, G

    2002-02-01

    Class B floral homeotic genes specify the identity of petals and stamens during the development of angiosperm flowers. Recently, putative orthologs of these genes have been identified in different gymnosperms. Together, these genes constitute a clade, termed B genes. Here we report that diverse seed plants also contain members of a hitherto unknown sister clade of the B genes, termed B(sister) (B(s)) genes. We have isolated members of the B(s) clade from the gymnosperm Gnetum gnemon, the monocotyledonous angiosperm Zea mays and the eudicots Arabidopsis thaliana and Antirrhinum majus. In addition, MADS-box genes from the basal angiosperm Asarum europaeum and the eudicot Petunia hybrida were identified as B(s) genes. Comprehensive expression studies revealed that B(s) genes are mainly transcribed in female reproductive organs (ovules and carpel walls). This is in clear contrast to the B genes, which are predominantly expressed in male reproductive organs (and in angiosperm petals). Our data suggest that the B(s) genes played an important role during the evolution of the reproductive structures in seed plants. The establishment of distinct B and B(s) gene lineages after duplication of an ancestral gene may have accompanied the evolution of male microsporophylls and female megasporophylls 400-300 million years ago. During flower evolution, expression of B(s) genes diversified, but the focus of expression remained in female reproductive organs. Our findings imply that a clade of highly conserved close relatives of class B floral homeotic genes has been completely overlooked until recently and awaits further evaluation of its developmental and evolutionary importance. Electronic supplementary material to this paper can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00438-001-0615-8.

  20. Taxonomy of the ant genus Proceratium Roger (Hymenoptera, Formicidae in the Afrotropical region with a revision of the P. arnoldi clade and description of four new species

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    Francisco Hita Garcia

    2014-10-01

    Full Text Available The taxonomy of the genus Proceratium Roger is updated for the Afrotropical region. We give an overview of the genus in the region, provide an illustrated identification key to the three clades (P. arnoldi, P. stictum and P. toschii clades and revise the P. arnoldi clade. Four new species from the P. arnoldi clade are described as new: P. sokoke sp. n. from Kenya, P. carri sp. n. from Mozambique, and P. nilo sp. n. and P. sali sp. n. from Tanzania. In order to integrate the new species into the existing taxonomic system we present an illustrated identification key to distinguish the seven Afrotropical species of the P. arnoldi clade. In addition, we provide accounts for all members of the P. arnoldi clade including detailed descriptions, diagnoses, taxonomic discussions, distribution data and high quality montage images.

  1. Tuber aztecorum sp. nov., a truffle species from Mexico belonging to the Maculatum clade (Tuberaceae, Pezizales

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    Gonzalo Guevara-Guerrero

    2018-02-01

    Full Text Available A new species of truffle, T. aztecorum, is described from central Mexico. Tuber aztecorum can be distinguished from other related Tuber species synoptically by a combination of morphological features including ascospore size, pellis cells with irregular thickness, cystidia, ascoma colour and associated host (Abies religiosa an endemic Abies species from central Mexico; sequence variation on the ITS rDNA also distinguishes T. aztecorum from related species. A phylogenetic analysis of the ITS rDNA demonstrates that T. aztecorum belongs to the Maculatum clade and is unique from other similar small, white-cream coloured Tuber species distributed in north-eastern Mexico such as T. castilloi and T. guevarai.

  2. Phylogenomic analyses of 539 highly informative loci dates a fully resolved time tree for the major clades of living turtles (Testudines).

    Science.gov (United States)

    Shaffer, H Bradley; McCartney-Melstad, Evan; Near, Thomas J; Mount, Genevieve G; Spinks, Phillip Q

    2017-10-01

    Accurate time-calibrated phylogenies are the centerpiece of many macroevolutionary studies, and the relationship between the size and scale of molecular data sets and the density and accuracy of fossil calibrations is a key element of time tree studies. Here, we develop a target capture array specifically for living turtles, compare its efficiency to an ultraconserved element (UCE) dataset, and present a time-calibrated molecular phylogeny based on 539 nuclear loci sequenced from 26 species representing the breadth of living turtle diversity plus outgroups. Our gene array, based on three fully sequenced turtle genomes, is 2.4 times more variable across turtles than a recently published UCE data set for an identical subset of 13 species, confirming that taxon-specific arrays return more informative data per sequencing effort than UCEs. We used our genomic data to estimate the ages of living turtle clades including a mid-late Triassic origin for crown turtles and a mid-Carboniferous split of turtles from their sister group, Archosauria. By specifically excluding several of the earliest potential crown turtle fossils and limiting the age of fossil calibration points to the unambiguous crown lineage Caribemys oxfordiensis from the Late Jurassic (Oxfordian, 163.5-157.3Ma) we corroborate a relatively ancient age for living turtles. We also provide novel age estimates for five of the ten testudine families containing more than a single species, as well as several intrafamilial clades. Most of the diversity of crown turtles appears to date to the Paleogene, well after the Cretaceous-Paleogene mass extinction 66mya. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Vegaviidae, a new clade of southern diving birds that survived the K/T boundary

    Science.gov (United States)

    Agnolín, Federico L.; Egli, Federico Brissón; Chatterjee, Sankar; Marsà, Jordi Alexis Garcia; Novas, Fernando E.

    2017-12-01

    The fossil record of Late Cretaceous-Paleogene modern birds in the Southern Hemisphere includes the Maastrichtian Neogaeornis wetzeli from Chile, Polarornis gregorii and Vegavis iaai from Antarctica, and Australornis lovei from the Paleogene of New Zealand. The recent finding of a new and nearly complete Vegavis skeleton constitutes the most informative source for anatomical comparisons among Australornis, Polarornis, and Vegavis. The present contribution includes, for the first time, Vegavis, Polarornis, and Australornis in a comprehensive phylogenetic analysis. This analysis resulted in the recognition of these taxa as a clade of basal Anseriformes that we call Vegaviidae. Vegaviids share a combination of characters related to diving adaptations, including compact and thickened cortex of hindlimb bones, femur with anteroposteriorly compressed and bowed shaft, deep and wide popliteal fossa delimited by a medial ridge, tibiotarsus showing notably proximally expanded cnemial crests, expanded fibular crest, anteroposterior compression of the tibial shaft, and a tarsometatarsus with a strong transverse compression of the shaft. Isolated bones coming from the Cretaceous and Paleogene of South America, Antarctica, and New Zealand are also referred to here to Vegaviidae and support the view that these basal anseriforms were abundant and diverse at high southern latitudes. Moreover, vegaviids represent the first avian lineage to have definitely crossed the K-Pg boundary, supporting the idea that some avian clades were not affected by the end Mesozoic mass extinction event, countering previous interpretations. Recognition of Vegaviidae indicates that modern birds were diversified in southern continents by the Cretaceous and reinforces the hypothesis indicating the important role of Gondwana for the evolutionary history of Anseriformes and Neornithes as a whole.

  4. Effect of Salt on the Metabolism of ‘Candidatus Accumulibacter’ Clade I and II

    KAUST Repository

    Wang, Zhongwei; Dunne, Aislinn; van Loosdrecht, Mark C. M.; Saikaly, Pascal

    2018-01-01

    Saline wastewater is known to affect the performance of phosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) process. However, studies comparing the effect of salinity on different PAO clades are lacking. In this study, 'Candidatus Accumulibacter phosphatis' Clade I and II (hereafter referred to as PAOI and PAOII) were highly enriched (~90% in relative abundance as determined by quantitative FISH) in the form of granules in two sequencing batch reactors. Anaerobic and aerobic batch experiments were conducted to evaluate the effect of salinity on the kinetics and stoichiometry of PAOI and PAOII. PAOI and PAOII communities showed different priority in using polyphosphate (poly-P) and glycogen to generate ATP in the anaerobic phase when exposed to salt, with PAOI depending more on intracellular poly-P degradation (e.g., the proportion of calculated ATP derived from poly-P increased by 5-6% at 0.256 mol/L NaCl or KCl) while PAOII on glycolysis of intracellularly stored glycogen (e.g., the proportion of calculated ATP derived from glycogen increased by 29-30% at 0.256 mol/L NaCl or KCl). In the aerobic phase, the loss of phosphate uptake capability was more pronounced in PAOII due to the higher energy cost to synthesize their larger glycogen pool compared to PAOI. For both PAOI and PAOII, aerobic conversion rates were more sensitive to salt than anaerobic conversion rates. Potassium (K) and sodium (Na) ions exhibited different effect regardless of the enriched PAO culture, suggesting that the composition of salt is an important factor to consider when studying the effect of salt on EBPR performance.

  5. Phylogeography of ostreopsis along west Pacific coast, with special reference to a novel clade from Japan.

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    Shinya Sato

    Full Text Available BACKGROUND: A dinoflagellate genus Ostreopsis is known as a potential producer of Palytoxin derivatives. Palytoxin is the most potent non-proteinaceous compound reported so far. There has been a growing number of reports on palytoxin-like poisonings in southern areas of Japan; however, the distribution of Ostreopsis has not been investigated so far. Morphological plasticity of Ostreopsis makes reliable microscopic identification difficult so the employment of molecular tools was desirable. METHODS/PRINCIPAL FINDING: In total 223 clones were examined from samples mainly collected from southern areas of Japan. The D8-D10 region of the nuclear large subunit rDNA (D8-D10 was selected as a genetic marker and phylogenetic analyses were conducted. Although most of the clones were unable to be identified, there potentially 8 putative species established during this study. Among them, Ostreopsis sp. 1-5 did not belong to any known clade, and each of them formed its own clade. The dominant species was Ostreopsis sp. 1, which accounted for more than half of the clones and which was highly toxic and only distributed along the Japanese coast. Comparisons between the D8-D10 and the Internal Transcribed Spacer (ITS region of the nuclear rDNA, which has widely been used for phylogenetic/phylogeographic studies in Ostreopsis, revealed that the D8-D10 was less variable than the ITS, making consistent and reliable phylogenetic reconstruction possible. CONCLUSIONS/SIGNIFICANCE: This study unveiled a surprisingly diverse and widespread distribution of Japanese Ostreopsis. Further study will be required to better understand the phylogeography of the genus. Our results posed the urgent need for the development of the early detection/warning systems for Ostreopsis, particularly for the widely distributed and strongly toxic Ostreopsis sp. 1. The D8-D10 marker will be suitable for these purposes.

  6. Effect of Salt on the Metabolism of ‘Candidatus Accumulibacter’ Clade I and II

    KAUST Repository

    Wang, Zhongwei

    2018-03-16

    Saline wastewater is known to affect the performance of phosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) process. However, studies comparing the effect of salinity on different PAO clades are lacking. In this study, \\'Candidatus Accumulibacter phosphatis\\' Clade I and II (hereafter referred to as PAOI and PAOII) were highly enriched (~90% in relative abundance as determined by quantitative FISH) in the form of granules in two sequencing batch reactors. Anaerobic and aerobic batch experiments were conducted to evaluate the effect of salinity on the kinetics and stoichiometry of PAOI and PAOII. PAOI and PAOII communities showed different priority in using polyphosphate (poly-P) and glycogen to generate ATP in the anaerobic phase when exposed to salt, with PAOI depending more on intracellular poly-P degradation (e.g., the proportion of calculated ATP derived from poly-P increased by 5-6% at 0.256 mol/L NaCl or KCl) while PAOII on glycolysis of intracellularly stored glycogen (e.g., the proportion of calculated ATP derived from glycogen increased by 29-30% at 0.256 mol/L NaCl or KCl). In the aerobic phase, the loss of phosphate uptake capability was more pronounced in PAOII due to the higher energy cost to synthesize their larger glycogen pool compared to PAOI. For both PAOI and PAOII, aerobic conversion rates were more sensitive to salt than anaerobic conversion rates. Potassium (K) and sodium (Na) ions exhibited different effect regardless of the enriched PAO culture, suggesting that the composition of salt is an important factor to consider when studying the effect of salt on EBPR performance.

  7. Effect of Salt on the Metabolism of ‘Candidatus Accumulibacter’ Clade I and II

    Directory of Open Access Journals (Sweden)

    Zhongwei Wang

    2018-03-01

    Full Text Available Saline wastewater is known to affect the performance of phosphate-accumulating organisms (PAOs in enhanced biological phosphorus removal (EBPR process. However, studies comparing the effect of salinity on different PAO clades are lacking. In this study, ‘Candidatus Accumulibacter phosphatis’ Clade I and II (hereafter referred to as PAOI and PAOII were highly enriched (∼90% in relative abundance as determined by quantitative FISH in the form of granules in two sequencing batch reactors. Anaerobic and aerobic batch experiments were conducted to evaluate the effect of salinity on the kinetics and stoichiometry of PAOI and PAOII. PAOI and PAOII communities showed different priority in using polyphosphate (poly-P and glycogen to generate ATP in the anaerobic phase when exposed to salt, with PAOI depending more on intracellular poly-P degradation (e.g., the proportion of calculated ATP derived from poly-P increased by 5–6% at 0.256 mol/L NaCl or KCl while PAOII on glycolysis of intracellularly stored glycogen (e.g., the proportion of calculated ATP derived from glycogen increased by 29–30% at 0.256 mol/L NaCl or KCl. In the aerobic phase, the loss of phosphate uptake capability was more pronounced in PAOII due to the higher energy cost to synthesize their larger glycogen pool compared to PAOI. For both PAOI and PAOII, aerobic conversion rates were more sensitive to salt than anaerobic conversion rates. Potassium (K+ and sodium (Na+ ions exhibited different effect regardless of the enriched PAO culture, suggesting that the composition of salt is an important factor to consider when studying the effect of salt on EBPR performance.

  8. Novel H5N8 clade 2.3.4.4 highly pathogenic avian influenza virus in wild awuatic birds, Russia, 2016

    Science.gov (United States)

    H5N1 high pathogenicity avian influenza virus (HPAIV) emerged in 1996 in Guangdong China (Gs/GD) and has evolved into multiple genetic clades. Since 2008, HPAIV H5 clade 2.3.4 with N2, N5 and N8 neuraminidase subtypes have been identified in mainland China and outbreak of HPAIV H5N8 clade 2.3.4.4 ou...

  9. Draft genome and sequence variant data of the oomycete Pythium insidiosum strain Pi45 from the phylogenetically-distinct Clade-III

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    Weerayuth Kittichotirat

    2017-12-01

    Full Text Available Pythium insidiosum is a unique oomycete microorganism, capable of infecting humans and animals. The organism can be phylogenetically categorized into three distinct clades: Clade-I (strains from the Americas; Clade-II (strains from Asia and Australia, and Clade–III (strains from Thailand and the United States. Two draft genomes of the P. insidiosum Clade-I strain CDC-B5653 and Clade-II strain Pi-S are available in the public domain. The genome of P. insidiosum from the distinct Clade-III, which is distantly-related to the other two clades, is lacking. Here, we report the draft genome sequence of the P. insidiosum strain Pi45 (also known as MCC13; isolated from a Thai patient with pythiosis; accession numbers BCFM01000001-BCFM01017277 as a representative strain of the phylogenetically-distinct Clade-III. We also report a genome-scale data set of sequence variants (i.e., SNPs and INDELs found in P. insidiosum (accessible online at the Mendeley database: http://dx.doi.org/10.17632/r75799jy6c.1. Keywords: Pythium insidiosum, Pythiosis, Draft genome, Sequence variant

  10. Efficacy of a Recombinant Turkey Herpesvirus H5 Vaccine Against Challenge With H5N1 Clades 1.1.2 and 2.3.2.1 Highly Pathogenic Avian Influenza Viruses in Domestic Ducks (Anas platyrhynchos domesticus).

    Science.gov (United States)

    Pantin-Jackwood, Mary J; Kapczynski, Darrell R; DeJesus, Eric; Costa-Hurtado, Mar; Dauphin, Gwenaelle; Tripodi, Astrid; Dunn, John R; Swayne, David E

    2016-03-01

    Domestic ducks are the second most abundant poultry species in many Asian countries and have played a critical role in the epizootiology of H5N1 highly pathogenic avian influenza (HPAI).In this study, the protective efficacy of a live recombinant vector vaccine based on a turkey herpesvirus (HVT) expressing the H5 gene from a clade 2.2 H5N1 HPAI strain (A/Swan/Hungary/4999/ 2006) (rHVT-H5/2.2), given at 3 days of age, was examined in Pekin ducks (Anas platyrhynchos domesticus). The vaccine was given alone or in combination with an inactivated H5N1 clade 2.3.2.1 reverse genetic (rgGD/2.3.2.1) vaccine given at 16 days of age, either as a single vaccination or in a prime-boost regime. At 30 days of age, ducks were challenged with one of two H5N1 HPAI viruses: A/duck/Vietnam/NCVD-2721/2013 (clade 1.1.2) or A/duck/Vietnam/NCVD-1584/2012 (clade 2.3.2.1.C). These viruses produced 100% mortality in less than 5 days in nonvaccinated control ducks. Ducks vaccinated with the rgGD/2.3.2.1 vaccine, with or without the rHVT-H5/2.2 vaccine, were 90%-100% protected against mortality after challenge with either of the two H5N1 HPAI viruses. The rHVT-H5/2.2 vaccine alone, however, conferred only 30% protection against mortality after challenge with either H5N1 HPAI virus; the surviving ducks from these groups shed higher amount of virus and for longer than the single-vaccinated rgGD/2.3.2.1 group. Despite low protection, ducks vaccinated with the rHVT-H5/2.2 vaccine and challenged with the clade 1.1.2 Vietnam virus had a longer mean death time than nonvaccinated controls (P = 0.02). A booster effect was found on reduction of virus shedding when using both vaccines, with lower oropharyngeal viral titers at 4 days after challenge with either HPAI virus (P study demonstrates the suboptimal protection with the rHVT-H5/2.2 vaccine given alone in Pekin ducks against H5N1 HPAI viruses and only a minor additive effect on virus shedding reduction when used with an inactivated vaccine in a

  11. One-dimensional TRFLP-SSCP is an effective DNA fingerprinting strategy for soil Archaea that is able to simultaneously differentiate broad taxonomic clades based on terminal fragment length polymorphisms and closely related sequences based on single stranded conformation polymorphisms.

    Science.gov (United States)

    Swanson, Colby A; Sliwinski, Marek K

    2013-09-01

    DNA fingerprinting methods provide a means to rapidly compare microbial assemblages from environmental samples without the need to first cultivate species in the laboratory. The profiles generated by these techniques are able to identify statistically significant temporal and spatial patterns, correlations to environmental gradients, and biological variability to estimate the number of replicates for clone libraries or next generation sequencing (NGS) surveys. Here we describe an improved DNA fingerprinting technique that combines terminal restriction fragment length polymorphisms (TRFLP) and single stranded conformation polymorphisms (SSCP) so that both can be used to profile a sample simultaneously rather than requiring two sequential steps as in traditional two-dimensional (2-D) gel electrophoresis. For the purpose of profiling Archaeal 16S rRNA genes from soil, the dynamic range of this combined 1-D TRFLP-SSCP approach was superior to TRFLP and SSCP. 1-D TRFLP-SSCP was able to distinguish broad taxonomic clades with genetic distances greater than 10%, such as Euryarchaeota and the Thaumarchaeal clades g_Ca. Nitrososphaera (formerly 1.1b) and o_NRP-J (formerly 1.1c) better than SSCP. In addition, 1-D TRFLP-SSCP was able to simultaneously distinguish closely related clades within a genus such as s_SCA1145 and s_SCA1170 better than TRFLP. We also tested the utility of 1-D TRFLP-SSCP fingerprinting of environmental assemblages by comparing this method to the generation of a 16S rRNA clone library of soil Archaea from a restored Tallgrass prairie. This study shows 1-D TRFLP-SSCP fingerprinting provides a rapid and phylogenetically informative screen of Archaeal 16S rRNA genes in soil samples. © 2013.

  12. A replicating modified vaccinia tiantan strain expressing an avian-derived influenza H5N1 hemagglutinin induce broadly neutralizing antibodies and cross-clade protective immunity in mice.

    Directory of Open Access Journals (Sweden)

    Haixia Xiao

    Full Text Available To combat the possibility of a zoonotic H5N1 pandemic in a timely fashion, it is necessary to develop a vaccine that would confer protection against homologous and heterologous human H5N1 influenza viruses. Using a replicating modified vaccinia virus Tian Tan strain (MVTT as a vaccine vector, we constructed MVTTHA-QH and MVTTHA-AH, which expresses the H5 gene of a goose-derived Qinghai strain A/Bar-headed Goose/Qinghai/1/2005 or human-derived Anhui Strain A/Anhui/1/2005. The immunogenicity profiles of both vaccine candidates were evaluated. Vaccination with MVTTHA-QH induced a significant level of neutralizing antibodies (Nabs against a homologous strain and a wide range of H5N1 pseudoviruses (clades 1, 2.1, 2.2, 2.3.2, and 2.3.4. Neutralization tests (NT and Haemagglutination inhibition (HI antibodies inhibit the live autologous virus as well as a homologous A/Xingjiang/1/2006 and a heterologous A/Vietnam/1194/2004, representing two human isolates from clade 2.2 and clade 1, respectively. Importantly, mice vaccinated with intranasal MVTTHA-QH were completely protected from challenge with lethal dosages of A/Bar-headed Goose/Qinghai/1/2005 and the A/Viet Nam/1194/2004, respectively, but not control mice that received a mock MVTTS vaccine. However, MVTTHA-AH induced much lower levels of NT against its autologous strain. Our results suggest that it is feasible to use the H5 gene from A/Bar-headed Goose/Qinghai/1/2005 to construct an effective vaccine, when using MVTT as a vector, to prevent infections against homologous and genetically divergent human H5N1 influenza viruses.

  13. The Transcriptomes of Xiphinema index and Longidorus elongatus Suggest Independent Acquisition of Some Plant Parasitism Genes by Horizontal Gene Transfer in Early-Branching Nematodes.

    Science.gov (United States)

    Danchin, Etienne G J; Perfus-Barbeoch, Laetitia; Rancurel, Corinne; Thorpe, Peter; Da Rocha, Martine; Bajew, Simon; Neilson, Roy; Guzeeva, Elena Sokolova; Da Silva, Corinne; Guy, Julie; Labadie, Karine; Esmenjaud, Daniel; Helder, Johannes; Jones, John T; den Akker, Sebastian Eves-van

    2017-10-23

    Nematodes have evolved the ability to parasitize plants on at least four independent occasions, with plant parasites present in Clades 1, 2, 10 and 12 of the phylum. In the case of Clades 10 and 12, horizontal gene transfer of plant cell wall degrading enzymes from bacteria and fungi has been implicated in the evolution of plant parasitism. We have used ribonucleic acid sequencing (RNAseq) to generate reference transcriptomes for two economically important nematode species, Xiphinema index and Longidorus elongatus , representative of two genera within the early-branching Clade 2 of the phylum Nematoda. We used a transcriptome-wide analysis to identify putative horizontal gene transfer events. This represents the first in-depth transcriptome analysis from any plant-parasitic nematode of this clade. For each species, we assembled ~30 million Illumina reads into a reference transcriptome. We identified 62 and 104 transcripts, from X. index and L. elongatus , respectively, that were putatively acquired via horizontal gene transfer. By cross-referencing horizontal gene transfer prediction with a phylum-wide analysis of Pfam domains, we identified Clade 2-specific events. Of these, a GH12 cellulase from X. index was analysed phylogenetically and biochemically, revealing a likely bacterial origin and canonical enzymatic function. Horizontal gene transfer was previously shown to be a phenomenon that has contributed to the evolution of plant parasitism among nematodes. Our findings underline the importance and the extensiveness of this phenomenon in the evolution of plant-parasitic life styles in this speciose and widespread animal phylum.

  14. Two novel Fusarium species that cause canker disease of prickly ash (Zanthoxylum bungeanum) in northern China form a novel clade with Fusarium torreyae.

    Science.gov (United States)

    Zhou, Xue; O'Donnell, Kerry; Aoki, Takayuki; Smith, Jason A; Kasson, Matthew T; Cao, Zhi-Min

    2016-01-01

    Canker disease of prickly ash (Zanthoxylum bungeanum) has caused a decline in the production of this economically important spice in northern China in the past 25 y. To identify the etiological agent, 38 fungal isolates were recovered from symptomatic tissues from trees in five provinces in China. These isolates were identified by conducting BLASTN queries of NCBI GenBank and phylogenetic analyses of DNA sequence data from the nuclear ribosomal internal transcribed spacer region (ITS rDNA), a portion of the translation elongation factor 1-α (TEF1) gene, and genes encoding RNA polymerase II largest (RPB1) and second largest (RPB2) subunits. Results of these analyses suggested that 30/38 isolates belonged to two novel fusaria most closely related to the Florida torreya (Torreya taxifolia Arn.) pathogen, Fusarium torreyae in Florida and Georgia. These three canker-inducing tree pathogens form a novel clade within Fusarium here designated the F. torreyae species complex (FTOSC). BLASTN queries of GenBank also revealed that 5/38 isolates recovered from cankers represented an undescribed phylogenetic species within the F. solani species complex (FSSC) designated FSSC 6. Stem inoculations of three fusaria on Z. bungeanum resulted in consistent canker symptoms from which these three fusaria were recovered. The two novel fusaria, however, induced significantly larger lesions than FSSC 6. Herein, the two novel prickly ash pathogens are formally described as F. zanthoxyli and F. continuum. © 2016 by The Mycological Society of America.

  15. Phylogenetic analysis of Melon chlorotic leaf curl virus from Guatemala: Another emergent species in the Squash leaf curl virus clade

    KAUST Repository

    Brown, J.K.; Mills-Lujan, K.; Idris, Ali

    2011-01-01

    divergent owing in part to recombination, but also due to the accumulation of a substantial number of mutations. In addition they are differentially host-adapted, as has been documented for other cucurbit-infecting, bean-adapted, species in the SLCV clade

  16. Characteristics of primary infection of a European human immunodeficiency virus type 1 clade B isolate in chimpanzees

    NARCIS (Netherlands)

    Bogers, W. M.; Koornstra, W. H.; Dubbes, R. H.; ten Haaft, P. J.; Verstrepen, B. E.; Jhagjhoorsingh, S. S.; Haaksma, A. G.; Niphuis, H.; Laman, J. D.; Norley, S.; Schuitemaker, H.; Goudsmit, J.; Hunsmann, G.; Heeney, J. L.; Wigzell, H.

    1998-01-01

    The aim of the study was to select, from a panel of candidate European human immunodeficiency virus type 1 (HIV-1) clade B primary virus isolates, one isolate based on replication properties in chimpanzee peripheral blood mononuclear cells (PBMC). Secondly, to evaluate the in vivo kinetics of

  17. Changing patterns in HIV-1 non-B clade prevalence and diversity in Italy over three decades

    DEFF Research Database (Denmark)

    Lai, A; Riva, C; Marconi, A

    2010-01-01

    HIV-1 non-B subtypes have recently entered Western Europe following immigration from other regions. The distribution of non-B clades and their association with demographic factors, over the entire course of the HIV-1 epidemic, have not been fully investigated in Italy....

  18. Strigolactone levels in dicot roots are determined by an ancestral symbiosis-regulated clade of the PHYTOENE SYNTHASE gene family

    NARCIS (Netherlands)

    Stauder, Ron; Welsch, Ralf; Camagna, Maurizio; Kohlen, Wouter; Balcke, Gerd U.; Tissier, Alain; Walter, Michael H.

    2018-01-01

    Strigolactones (SLs) are apocarotenoid phytohormones synthesized from carotenoid precursors. They are produced most abundantly in roots for exudation into the rhizosphere to cope with mineral nutrient starvation through support of root symbionts. Abscisic acid (ABA) is another apocarotenoid

  19. Brain structure evolution in a basal vertebrate clade: evidence from phylogenetic comparative analysis of cichlid fishes

    Directory of Open Access Journals (Sweden)

    Kolm Niclas

    2009-09-01

    Full Text Available Abstract Background The vertebrate brain is composed of several interconnected, functionally distinct structures and much debate has surrounded the basic question of how these structures evolve. On the one hand, according to the 'mosaic evolution hypothesis', because of the elevated metabolic cost of brain tissue, selection is expected to target specific structures mediating the cognitive abilities which are being favored. On the other hand, the 'concerted evolution hypothesis' argues that developmental constraints limit such mosaic evolution and instead the size of the entire brain varies in response to selection on any of its constituent parts. To date, analyses of these hypotheses of brain evolution have been limited to mammals and birds; excluding Actinopterygii, the basal and most diverse class of vertebrates. Using a combination of recently developed phylogenetic multivariate allometry analyses and comparative methods that can identify distinct rates of evolution, even in highly correlated traits, we studied brain structure evolution in a highly variable clade of ray-finned fishes; the Tanganyikan cichlids. Results Total brain size explained 86% of the variance in brain structure volume in cichlids, a lower proportion than what has previously been reported for mammals. Brain structures showed variation in pair-wise allometry suggesting some degree of independence in evolutionary changes in size. This result is supported by variation among structures on the strength of their loadings on the principal size axis of the allometric analysis. The rate of evolution analyses generally supported the results of the multivariate allometry analyses, showing variation among several structures in their evolutionary patterns. The olfactory bulbs and hypothalamus were found to evolve faster than other structures while the dorsal medulla presented the slowest evolutionary rate. Conclusion Our results favor a mosaic model of brain evolution, as certain

  20. Methods for the quantitative comparison of molecular estimates of clade age and the fossil record.

    Science.gov (United States)

    Clarke, Julia A; Boyd, Clint A

    2015-01-01

    Approaches quantifying the relative congruence, or incongruence, of molecular divergence estimates and the fossil record have been limited. Previously proposed methods are largely node specific, assessing incongruence at particular nodes for which both fossil data and molecular divergence estimates are available. These existing metrics, and other methods that quantify incongruence across topologies including entirely extinct clades, have so far not taken into account uncertainty surrounding both the divergence estimates and the ages of fossils. They have also treated molecular divergence estimates younger than previously assessed fossil minimum estimates of clade age as if they were the same as cases in which they were older. However, these cases are not the same. Recovered divergence dates younger than compared oldest known occurrences require prior hypotheses regarding the phylogenetic position of the compared fossil record and standard assumptions about the relative timing of morphological and molecular change to be incorrect. Older molecular dates, by contrast, are consistent with an incomplete fossil record and do not require prior assessments of the fossil record to be unreliable in some way. Here, we compare previous approaches and introduce two new descriptive metrics. Both metrics explicitly incorporate information on uncertainty by utilizing the 95% confidence intervals on estimated divergence dates and data on stratigraphic uncertainty concerning the age of the compared fossils. Metric scores are maximized when these ranges are overlapping. MDI (minimum divergence incongruence) discriminates between situations where molecular estimates are younger or older than known fossils reporting both absolute fit values and a number score for incompatible nodes. DIG range (divergence implied gap range) allows quantification of the minimum increase in implied missing fossil record induced by enforcing a given set of molecular-based estimates. These metrics are used

  1. The Tomato Terpene Synthase Gene Family1[W][OA

    Science.gov (United States)

    Falara, Vasiliki; Akhtar, Tariq A.; Nguyen, Thuong T.H.; Spyropoulou, Eleni A.; Bleeker, Petra M.; Schauvinhold, Ines; Matsuba, Yuki; Bonini, Megan E.; Schilmiller, Anthony L.; Last, Robert L.; Schuurink, Robert C.; Pichersky, Eran

    2011-01-01

    Compounds of the terpenoid class play numerous roles in the interactions of plants with their environment, such as attracting pollinators and defending the plant against pests. We show here that the genome of cultivated tomato (Solanum lycopersicum) contains 44 terpene synthase (TPS) genes, including 29 that are functional or potentially functional. Of these 29 TPS genes, 26 were expressed in at least some organs or tissues of the plant. The enzymatic functions of eight of the TPS proteins were previously reported, and here we report the specific in vitro catalytic activity of 10 additional tomato terpene synthases. Many of the tomato TPS genes are found in clusters, notably on chromosomes 1, 2, 6, 8, and 10. All TPS family clades previously identified in angiosperms are also present in tomato. The largest clade of functional TPS genes found in tomato, with 12 members, is the TPS-a clade, and it appears to encode only sesquiterpene synthases, one of which is localized to the mitochondria, while the rest are likely cytosolic. A few additional sesquiterpene synthases are encoded by TPS-b clade genes. Some of the tomato sesquiterpene synthases use z,z-farnesyl diphosphate in vitro as well, or more efficiently than, the e,e-farnesyl diphosphate substrate. Genes encoding monoterpene synthases are also prevalent, and they fall into three clades: TPS-b, TPS-g, and TPS-e/f. With the exception of two enzymes involved in the synthesis of ent-kaurene, the precursor of gibberellins, no other tomato TPS genes could be demonstrated to encode diterpene synthases so far. PMID:21813655

  2. Real-time PCR reveals a high incidence of Symbiodinium clade D at low levels in four scleractinian corals across the Great Barrier Reef : implications for symbiont shuffling

    NARCIS (Netherlands)

    Mieog, J. C.; van Oppen, M. J. H.; Cantin, N. E.; Stam, W. T.; Olsen, J. L.

    Reef corals form associations with an array of genetically and physiologically distinct endosymbionts from the genus Symbiodinium. Some corals harbor different clades of symbionts simultaneously, and over time the relative abundances of these clades may change through a process called symbiont

  3. Unique Phylogenetic Lineage Found in the Fusarium-like Clade after Re-examining BCCM/IHEM Fungal Culture Collection Material.

    Science.gov (United States)

    Triest, David; De Cremer, Koen; Piérard, Denis; Hendrickx, Marijke

    2016-09-01

    Recently, the Fusarium genus has been narrowed based upon phylogenetic analyses and a Fusarium -like clade was adopted. The few species of the Fusarium -like clade were moved to new, re-installed or existing genera or provisionally retained as " Fusarium ." Only a limited number of reference strains and DNA marker sequences are available for this clade and not much is known about its actual species diversity. Here, we report six strains, preserved by the Belgian fungal culture collection BCCM/IHEM as a Fusarium species, that belong to the Fusarium -like clade. They showed a slow growth and produced pionnotes, typical morphological characteristics of many Fusarium -like species. Multilocus sequencing with comparative sequence analyses in GenBank and phylogenetic analyses, using reference sequences of type material, confirmed that they were indeed member of the Fusarium -like clade. One strain was identified as "Fusarium" ciliatum whereas another strain was identified as Fusicolla merismoides . The four remaining strains were shown to represent a unique phylogenetic lineage in the Fusarium -like clade and were also found morphologically distinct from other members of the Fusarium -like clade. Based upon phylogenetic considerations, a new genus, Pseudofusicolla gen. nov., and a new species, Pseudofusicolla belgica sp. nov., were installed for this lineage. A formal description is provided in this study. Additional sampling will be required to gather isolates other than the historical strains presented in the present study as well as to further reveal the actual species diversity in the Fusarium -like clade.

  4. Insights on the evolutionary origin of Detarioideae, a clade of ecologically dominant tropical African trees.

    Science.gov (United States)

    de la Estrella, Manuel; Forest, Félix; Wieringa, Jan J; Fougère-Danezan, Marie; Bruneau, Anne

    2017-06-01

    African tropical forests are generally considered less diverse than their Neotropical and Asian counterparts. By contrast, the Detarioideae is much more diverse in Africa than in South America and Asia. To better understand the evolution of this contrasting diversity pattern, we investigated the biogeographical and ecological origin of this subfamily, testing whether they originated in dry biomes surrounding the Tethys Seaway as currently hypothesized for many groups of Leguminosae. We constructed the largest time-calibrated phylogeny for the subfamily to date, reconstructed ancestral states for geography and biome/habitat, estimated diversification and extinction rates, and evaluated biome/habitat and geographic shifts in Detarioideae. The ancestral habitat of Detarioideae is postulated to be a primary forest (terra firme) originated in Africa-South America, in the early Palaeocene, after which several biome/habitat and geographic shifts occurred. The origin of Detarioideae is older than previous estimates, which postulated a dry (succulent) biome origin according to the Tethys Seaway hypothesis, and instead we reveal a post Gondwana and terra firme origin for this early branching clade of legumes. Detarioideae include some of the most dominant trees in evergreen forests and have likely played a pivotal role in shaping continental African forest diversity. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  5. Feeding ecology and sexual dimorphism in a speciose flower beetle clade (Hopliini: Scarabaeidae

    Directory of Open Access Journals (Sweden)

    Jonathan F. Colville

    2018-06-01

    Full Text Available The relationship between feeding ecology and sexual dimorphism is examined in a speciose South African monkey beetle clade. We test whether feeding and mating at a fixed site (embedding guild is associated with greater levels of sexual dimorphism and possibly sexual selection than species using unpredictable feeding resources (non-embedding guild. Sexual dimorphism was measured using a point scoring system for hind leg and colour across the two feeding guilds for >50% of the regional fauna. Quantification of hind leg dimorphism using a scoring system and allometric scaling were used to identify traits subject to sexual selection. Feeding guild had a significant effect on hind leg dimorphism, with embedders having high and non-embedders low scores. The sessile and defendable distribution of females on stable platform flowers may favour contests and associated hind leg weaponry. In contrast, degree of colour dimorphism between the sexes was not associated with any particular feeding guild, and may serve to reduce male conflict and combat. Embedder males had high proportions (∼76% of species with positive allometric slopes for almost all hind leg traits. For male non-embedders, only ∼37% of species showed positive scaling relationships. Phylogenetic data, in conjunction with behavioural data on the function of leg weaponry and visual signalling among males is needed to better understand the link between sexual dimorphism and sexual selection in the radiation of the monkey beetles.

  6. Contrasting patterns of Andean diversification among three diverse clades of Neotropical clearwing butterflies.

    Science.gov (United States)

    Chazot, Nicolas; De-Silva, Donna Lisa; Willmott, Keith R; Freitas, André V L; Lamas, Gerardo; Mallet, James; Giraldo, Carlos E; Uribe, Sandra; Elias, Marianne

    2018-04-01

    The Neotropical region is the most biodiverse on Earth, in a large part due to the highly diverse tropical Andean biota. The Andes are a potentially important driver of diversification within the mountains and for neighboring regions. We compared the role of the Andes in diversification among three subtribes of Ithomiini butterflies endemic to the Neotropics, Dircennina, Oleriina, and Godyridina. The diversification patterns of Godyridina have been studied previously. Here, we generate the first time-calibrated phylogeny for the largest ithomiine subtribe, Dircennina, and we reanalyze a published phylogeny of Oleriina to test different biogeographic scenarios involving the Andes within an identical framework. We found common diversification patterns across the three subtribes, as well as major differences. In Dircennina and Oleriina, our results reveal a congruent pattern of diversification related to the Andes with an Andean origin, which contrasts with the Amazonian origin and multiple Andean colonizations of Godyridina. In each of the three subtribes, a clade diversified in the Northern Andes at a faster rate. Diversification within Amazonia occurred in Oleriina and Godyridina, while virtually no speciation occurred in Dircennina in this region. Dircennina was therefore characterized by higher diversification rates within the Andes compared to non-Andean regions, while in Oleriina and Godyridina, we found no difference between these regions. Our results and discussion highlight the importance of comparative approaches in biogeographic studies.

  7. Early evolution of the angiosperm clade Asteraceae in the Cretaceous of Antarctica.

    Science.gov (United States)

    Barreda, Viviana D; Palazzesi, Luis; Tellería, Maria C; Olivero, Eduardo B; Raine, J Ian; Forest, Félix

    2015-09-01

    The Asteraceae (sunflowers and daisies) are the most diverse family of flowering plants. Despite their prominent role in extant terrestrial ecosystems, the early evolutionary history of this family remains poorly understood. Here we report the discovery of a number of fossil pollen grains preserved in dinosaur-bearing deposits from the Late Cretaceous of Antarctica that drastically pushes back the timing of assumed origin of the family. Reliably dated to ∼76-66 Mya, these specimens are about 20 million years older than previously known records for the Asteraceae. Using a phylogenetic approach, we interpreted these fossil specimens as members of an extinct early diverging clade of the family, associated with subfamily Barnadesioideae. Based on a molecular phylogenetic tree calibrated using fossils, including the ones reported here, we estimated that the most recent common ancestor of the family lived at least 80 Mya in Gondwana, well before the thermal and biogeographical isolation of Antarctica. Most of the early diverging lineages of the family originated in a narrow time interval after the K/P boundary, 60-50 Mya, coinciding with a pronounced climatic warming during the Late Paleocene and Early Eocene, and the scene of a dramatic rise in flowering plant diversity. Our age estimates reduce earlier discrepancies between the age of the fossil record and previous molecular estimates for the origin of the family, bearing important implications in the evolution of flowering plants in general.

  8. Bacterial clade with the ribosomal RNA operon on a small plasmid rather than the chromosome.

    Science.gov (United States)

    Anda, Mizue; Ohtsubo, Yoshiyuki; Okubo, Takashi; Sugawara, Masayuki; Nagata, Yuji; Tsuda, Masataka; Minamisawa, Kiwamu; Mitsui, Hisayuki

    2015-11-17

    rRNA is essential for life because of its functional importance in protein synthesis. The rRNA (rrn) operon encoding 16S, 23S, and 5S rRNAs is located on the "main" chromosome in all bacteria documented to date and is frequently used as a marker of chromosomes. Here, our genome analysis of a plant-associated alphaproteobacterium, Aureimonas sp. AU20, indicates that this strain has its sole rrn operon on a small (9.4 kb), high-copy-number replicon. We designated this unusual replicon carrying the rrn operon on the background of an rrn-lacking chromosome (RLC) as the rrn-plasmid. Four of 12 strains close to AU20 also had this RLC/rrn-plasmid organization. Phylogenetic analysis showed that those strains having the RLC/rrn-plasmid organization represented one clade within the genus Aureimonas. Our finding introduces a previously unaddressed viewpoint into studies of genetics, genomics, and evolution in microbiology and biology in general.

  9. A new clade, based on partial LSU rDNA sequences, of unarmoured dinoflagellates.

    Science.gov (United States)

    Reñé, Albert; de Salas, Miguel; Camp, Jordi; Balagué, Vanessa; Garcés, Esther

    2013-09-01

    The order Gymnodiniales comprises unarmoured dinoflagellates. However, the lack of sequences hindered determining the phylogenetic positions and systematic relationships of several gymnodinioid taxa. In this study, a monophyletic clade was defined for the species Ceratoperidinium margalefii Loeblich III, Gyrodinium falcatum Kofoid & Swezy, three Cochlodinium species, and two Gymnodinium-like dinoflagellates. Despite their substantial morphotypic differentiation, Cochlodinium cf. helix, G. falcatum and 'Gymnodinium' sp. 1 share a common shape of the acrobase. The phylogenetic data led to the following conclusions: (1) C. margalefii is closely related to several unarmoured dinoflagellates. Its sulcus shape has been observed for the first time. (2) G. falcatum was erroneously assigned to the genus Gyrodinium and is transferred to Ceratoperidinium (C. falcatum (Kofoid & Swezy) Reñé & de Salas comb. nov.). (3) The genus Cochlodinium is polyphyletic and thus artificial; our data support its separation into three different genera. (4) The two Gymnodinium-like species could not be morphologically or phylogenetically related to any other gymnodinioid species sequenced to date. While not all studied species have been definitively transferred to the correct genus, our study is a step forward in the classification of inconspicuous unarmoured dinoflagellates. The family Ceratoperidiniaeceae and the genus Ceratoperidinium are emended. Copyright © 2013 Elsevier GmbH. All rights reserved.

  10. Synchrotron scanning reveals amphibious ecomorphology in a new clade of bird-like dinosaurs

    Science.gov (United States)

    Cau, Andrea; Beyrand, Vincent; Voeten, Dennis F. A. E.; Fernandez, Vincent; Tafforeau, Paul; Stein, Koen; Barsbold, Rinchen; Tsogtbaatar, Khishigjav; Currie, Philip J.; Godefroit, Pascal

    2017-12-01

    Maniraptora includes birds and their closest relatives among theropod dinosaurs. During the Cretaceous period, several maniraptoran lineages diverged from the ancestral coelurosaurian bauplan and evolved novel ecomorphologies, including active flight, gigantism, cursoriality and herbivory. Propagation X-ray phase-contrast synchrotron microtomography of a well-preserved maniraptoran from Mongolia, still partially embedded in the rock matrix, revealed a mosaic of features, most of them absent among non-avian maniraptorans but shared by reptilian and avian groups with aquatic or semiaquatic ecologies. This new theropod, Halszkaraptor escuilliei gen. et sp. nov., is related to other enigmatic Late Cretaceous maniraptorans from Mongolia in a novel clade at the root of Dromaeosauridae. This lineage adds an amphibious ecomorphology to those evolved by maniraptorans: it acquired a predatory mode that relied mainly on neck hyperelongation for food procurement, it coupled the obligatory bipedalism of theropods with forelimb proportions that may support a swimming function, and it developed postural adaptations convergent with short-tailed birds.

  11. Plasmodium cynomolgi genome sequences provide insight into Plasmodium vivax and the monkey malaria clade.

    Science.gov (United States)

    Tachibana, Shin-Ichiro; Sullivan, Steven A; Kawai, Satoru; Nakamura, Shota; Kim, Hyunjae R; Goto, Naohisa; Arisue, Nobuko; Palacpac, Nirianne M Q; Honma, Hajime; Yagi, Masanori; Tougan, Takahiro; Katakai, Yuko; Kaneko, Osamu; Mita, Toshihiro; Kita, Kiyoshi; Yasutomi, Yasuhiro; Sutton, Patrick L; Shakhbatyan, Rimma; Horii, Toshihiro; Yasunaga, Teruo; Barnwell, John W; Escalante, Ananias A; Carlton, Jane M; Tanabe, Kazuyuki

    2012-09-01

    P. cynomolgi, a malaria-causing parasite of Asian Old World monkeys, is the sister taxon of P. vivax, the most prevalent malaria-causing species in humans outside of Africa. Because P. cynomolgi shares many phenotypic, biological and genetic characteristics with P. vivax, we generated draft genome sequences for three P. cynomolgi strains and performed genomic analysis comparing them with the P. vivax genome, as well as with the genome of a third previously sequenced simian parasite, Plasmodium knowlesi. Here, we show that genomes of the monkey malaria clade can be characterized by copy-number variants (CNVs) in multigene families involved in evasion of the human immune system and invasion of host erythrocytes. We identify genome-wide SNPs, microsatellites and CNVs in the P. cynomolgi genome, providing a map of genetic variation that can be used to map parasite traits and study parasite populations. The sequencing of the P. cynomolgi genome is a critical step in developing a model system for P. vivax research and in counteracting the neglect of P. vivax.

  12. The first freshwater mosasauroid (Upper Cretaceous, Hungary and a new clade of basal mosasauroids.

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    László Makádi

    Full Text Available Mosasauroids are conventionally conceived of as gigantic, obligatorily aquatic marine lizards (1000s of specimens from marine deposited rocks with a cosmopolitan distribution in the Late Cretaceous (90-65 million years ago [mya] oceans and seas of the world. Here we report on the fossilized remains of numerous individuals (small juveniles to large adults of a new taxon, Pannoniasaurus inexpectatus gen. et sp. nov. from the Csehbánya Formation, Hungary (Santonian, Upper Cretaceous, 85.3-83.5 mya that represent the first known mosasauroid that lived in freshwater environments. Previous to this find, only one specimen of a marine mosasauroid, cf. Plioplatecarpus sp., is known from non-marine rocks in Western Canada. Pannoniasaurus inexpectatus gen. et sp. nov. uniquely possesses a plesiomorphic pelvic anatomy, a non-mosasauroid but pontosaur-like tail osteology, possibly limbs like a terrestrial lizard, and a flattened, crocodile-like skull. Cladistic analysis reconstructs P. inexpectatus in a new clade of mosasauroids: (Pannoniasaurus (Tethysaurus (Yaguarasaurus, Russellosaurus. P. inexpectatus is part of a mixed terrestrial and freshwater faunal assemblage that includes fishes, amphibians turtles, terrestrial lizards, crocodiles, pterosaurs, dinosaurs and birds.

  13. Whole genome investigation of a divergent clade of the pathogen Streptococcus suis

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    Abiyad eBaig

    2015-11-01

    Full Text Available Streptococcus suis is a major porcine and zoonotic pathogen responsible for significant economic losses in the pig industry and an increasing number of human cases. Multiple isolates of S. suis show marked genomic diversity. Here we report the analysis of whole genome sequences of nine pig isolates that caused disease typical of S. suis and had phenotypic characteristics of S. suis, but their genomes were divergent from those of many other S. suis isolates. Comparison of protein sequences predicted from divergent genomes with those from normal S. suis reduced the size of core genome from 793 to only 397 genes. Divergence was clear if phylogenetic analysis was performed on reduced core genes and MLST alleles. Phylogenies based on certain other genes (16S rRNA, sodA, recN and cpn60 did not show divergence for all isolates, suggesting recombination between some divergent isolates with normal S. suis for these genes. Indeed, there is evidence of recent recombination between the divergent and normal S. suis genomes for 249 of 397 core genes. In addition, phylogenetic analysis based on the 16S rRNA gene and 132 genes that were conserved between the divergent isolates and representatives of the broader Streptococcus genus showed that divergent isolates were more closely related to S. suis. Six out of nine divergent isolates possessed a S. suis-like capsule region with variation in capsular gene sequences but the remaining three did not have a discrete capsule locus. The majority (40/70, of virulence-associated genes in normal S. suis were present in the divergent genomes. Overall, the divergent isolates extend the current diversity of S. suis species but the phenotypic similarities and the large amount of gene exchange with normal S. suis gives insufficient evidence to assign these isolates to a new species or subspecies. Further sampling and whole genome analysis of more isolates is warranted to understand the diversity of the species.

  14. Insights into the evolution and diversification of the AT-hook Motif Nuclear Localized gene family in land plants.

    Science.gov (United States)

    Zhao, Jianfei; Favero, David S; Qiu, Jiwen; Roalson, Eric H; Neff, Michael M

    2014-10-14

    Members of the ancient land-plant-specific transcription factor AT-Hook Motif Nuclear Localized (AHL) gene family regulate various biological processes. However, the relationships among the AHL genes, as well as their evolutionary history, still remain unexplored. We analyzed over 500 AHL genes from 19 land plant species, ranging from the early diverging Physcomitrella patens and Selaginella to a variety of monocot and dicot flowering plants. We classified the AHL proteins into three types (Type-I/-II/-III) based on the number and composition of their functional domains, the AT-hook motif(s) and PPC domain. We further inferred their phylogenies via Bayesian inference analysis and predicted gene gain/loss events throughout their diversification. Our analyses suggested that the AHL gene family emerged in embryophytes and further evolved into two distinct clades, with Type-I AHLs forming one clade (Clade-A), and the other two types together diversifying in another (Clade-B). The two AHL clades likely diverged before the separation of Physcomitrella patens from the vascular plant lineage. In angiosperms, Clade-A AHLs expanded into 5 subfamilies; while, the ones in Clade-B expanded into 4 subfamilies. Examination of their expression patterns suggests that the AHLs within each clade share similar expression patterns with each other; however, AHLs in one monophyletic clade exhibit distinct expression patterns from the ones in the other clade. Over-expression of a Glycine max AHL PPC domain in Arabidopsis thaliana recapitulates the phenotype observed when over-expressing its Arabidopsis thaliana counterpart. This result suggests that the AHL genes from different land plant species may share conserved functions in regulating plant growth and development. Our study further suggests that such functional conservation may be due to conserved physical interactions among the PPC domains of AHL proteins. Our analyses reveal a possible evolutionary scenario for the AHL gene family

  15. Evaluating rare amino acid substitutions (RGC_CAMs in a yeast model clade.

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    Kenneth Polzin

    Full Text Available When inferring phylogenetic relationships, not all sites in a sequence alignment are equally informative. One recently proposed approach that takes advantage of this inequality relies on sites that contain amino acids whose replacement requires multiple substitutions. Identifying these so-called RGC_CAM substitutions (after Rare Genomic Changes as Conserved Amino acids-Multiple substitutions requires that, first, at any given site in the amino acid sequence alignment, there must be a minimum of two different amino acids; second, each amino acid must be present in at least two taxa; and third, the amino acids must require a minimum of two nucleotide substitutions to replace each other. Although theory suggests that RGC_CAM substitutions are expected to be rare and less likely to be homoplastic, the informativeness of RGC_CAM substitutions has not been extensively evaluated in biological data sets. We investigated the quality of RGC_CAM substitutions by examining their degree of homoplasy and internode certainty in nearly 2.7 million aligned amino acid sites from 5,261 proteins from five species belonging to the yeast Saccharomyces sensu stricto clade whose phylogeny is well-established. We identified 2,647 sites containing RGC_CAM substitutions, a number that contrasts sharply with the 100,887 sites containing RGC_non-CAM substitutions (i.e., changes between amino acids that require only a single nucleotide substitution. We found that RGC_CAM substitutions had significantly lower homoplasy than RGC_non-CAM ones; specifically RGC_CAM substitutions showed a per-site average homoplasy index of 0.100, whereas RGC_non-CAM substitutions had a homoplasy index of 0.215. Internode certainty values were also higher for sites containing RGC_CAM substitutions than for RGC_non-CAM ones. These results suggest that RGC_CAM substitutions possess a strong phylogenetic signal and are useful markers for phylogenetic inference despite their rarity.

  16. The Eucalyptus terpene synthase gene family.

    Science.gov (United States)

    Külheim, Carsten; Padovan, Amanda; Hefer, Charles; Krause, Sandra T; Köllner, Tobias G; Myburg, Alexander A; Degenhardt, Jörg; Foley, William J

    2015-06-11

    Terpenoids are abundant in the foliage of Eucalyptus, providing the characteristic smell as well as being valuable economically and influencing ecological interactions. Quantitative and qualitative inter- and intra- specific variation of terpenes is common in eucalypts. The genome sequences of Eucalyptus grandis and E. globulus were mined for terpene synthase genes (TPS) and compared to other plant species. We investigated the relative expression of TPS in seven plant tissues and functionally characterized five TPS genes from E. grandis. Compared to other sequenced plant genomes, Eucalyptus grandis has the largest number of putative functional TPS genes of any sequenced plant. We discovered 113 and 106 putative functional TPS genes in E. grandis and E. globulus, respectively. All but one TPS from E. grandis were expressed in at least one of seven plant tissues examined. Genomic clusters of up to 20 genes were identified. Many TPS are expressed in tissues other than leaves which invites a re-evaluation of the function of terpenes in Eucalyptus. Our data indicate that terpenes in Eucalyptus may play a wider role in biotic and abiotic interactions than previously thought. Tissue specific expression is common and the possibility of stress induction needs further investigation. Phylogenetic comparison of the two investigated Eucalyptus species gives insight about recent evolution of different clades within the TPS gene family. While the majority of TPS genes occur in orthologous pairs some clades show evidence of recent gene duplication, as well as loss of function.

  17. Phylogenetic analysis of canine distemper virus in South America clade 1 reveals unique molecular signatures of the local epidemic.

    Science.gov (United States)

    Fischer, Cristine D B; Gräf, Tiago; Ikuta, Nilo; Lehmann, Fernanda K M; Passos, Daniel T; Makiejczuk, Aline; Silveira, Marcos A T; Fonseca, André S K; Canal, Cláudio W; Lunge, Vagner R

    2016-07-01

    Canine distemper virus (CDV) is a highly contagious pathogen for domestic dogs and several wild carnivore species. In Brazil, natural infection of CDV in dogs is very high due to the large non-vaccinated dog population, a scenario that calls for new studies on the molecular epidemiology. This study investigates the phylodynamics and amino-acid signatures of CDV epidemic in South America by analyzing a large dataset compiled from publicly available sequences and also by collecting new samples from Brazil. A population of 175 dogs with canine distemper (CD) signs was sampled, from which 89 were positive for CDV, generating 42 new CDV sequences. Phylogenetic analysis of the new and publicly available sequences revealed that Brazilian sequences mainly clustered in South America 1 (SA1) clade, which has its origin estimated to the late 1980's. The reconstruction of the demographic history in SA1 clade showed an epidemic expanding until the recent years, doubling in size every nine years. SA1 clade epidemic distinguished from the world CDV epidemic by the emergence of the R580Q strain, a very rare and potentially detrimental substitution in the viral genome. The R580Q substitution was estimated to have happened in one single evolutionary step in the epidemic history in SA1 clade, emerging shortly after introduction to the continent. Moreover, a high prevalence (11.9%) of the Y549H mutation was observed among the domestic dogs sampled here. This finding was associated (p<0.05) with outcome-death and higher frequency in mixed-breed dogs, the later being an indicator of a continuous exchange of CDV strains circulating among wild carnivores and domestic dogs. The results reported here highlight the diversity of the worldwide CDV epidemic and reveal local features that can be valuable for combating the disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Evolution of the intercontinental disjunctions in six continents in the Ampelopsis clade of the grape family (Vitaceae)

    Science.gov (United States)

    2012-01-01

    Background The Ampelopsis clade (Ampelopsis and its close allies) of the grape family Vitaceae contains ca. 43 species disjunctly distributed in Asia, Europe, North America, South America, Africa, and Australia, and is a rare example to study both the Northern and the Southern Hemisphere intercontinental disjunctions. We reconstruct the temporal and spatial diversification of the Ampelopsis clade to explore the evolutionary processes that have resulted in their intercontinental disjunctions in six continents. Results The Bayesian molecular clock dating and the likelihood ancestral area analyses suggest that the Ampelopsis clade most likely originated in North America with its crown group dated at 41.2 Ma (95% HPD 23.4 - 61.0 Ma) in the middle Eocene. Two independent Laurasian migrations into Eurasia are inferred to have occurred in the early Miocene via the North Atlantic land bridges. The ancestor of the Southern Hemisphere lineage migrated from North America to South America in the early Oligocene. The Gondwanan-like pattern of intercontinental disjunction is best explained by two long-distance dispersals: once from South America to Africa estimated at 30.5 Ma (95% HPD 16.9 - 45.9 Ma), and the other from South America to Australia dated to 19.2 Ma (95% HPD 6.7 - 22.3 Ma). Conclusions The global disjunctions in the Ampelopsis clade are best explained by a diversification model of North American origin, two Laurasian migrations, one migration into South America, and two post-Gondwanan long-distance dispersals. These findings highlight the importance of both vicariance and long distance dispersal in shaping intercontinental disjunctions of flowering plants. PMID:22316163

  19. The influence of sexual activity on the vaginal microbiota and Gardnerella vaginalis clade diversity in young women.

    Science.gov (United States)

    Vodstrcil, Lenka A; Twin, Jimmy; Garland, Suzanne M; Fairley, Christopher K; Hocking, Jane S; Law, Matthew G; Plummer, Erica L; Fethers, Katherine A; Chow, Eric P F; Tabrizi, Sepehr N; Bradshaw, Catriona S

    2017-01-01

    To examine the influence of sexual activity on the composition and consistency of the vaginal microbiota over time, and distribution of Gardnerella vaginalis clades in young women. Fifty-two participants from a university cohort were selected. Vaginal swabs were self-collected every 3-months for up to 12 months with 184 specimens analysed. The vaginal microbiota was characterised using Roche 454 V3/4 region 16S rRNA sequencing, and G.vaginalis clade typing by qPCR. A Lactobacillus crispatus dominated vaginal microbiota was associated with Caucasian ethnicity (adjusted relative risk ratio[ARRR] = 7.28, 95%CI:1.37,38.57,p = 0.020). An L.iners (ARRR = 17.51, 95%CI:2.18,140.33,p = 0.007) or G.vaginalis (ARRR = 14.03, 95%CI:1.22,160.69, p = 0.034) dominated microbiota was associated with engaging in penile-vaginal sex. Microbiota dominated by L.crispatus, L.iners or other lactobacilli exhibited greater longitudinal consistency of the bacterial communities present compared to ones dominated by heterogeneous non-lactobacilli (pvaginal sex (RRR = 9.55, 95%CI:1.33,68.38,p = 0.025) or were diagnosed with BV (RRR = 31.5, 95%CI:1.69,586.87,p = 0.021). Sexual activity and ethnicity influenced the composition of the vaginal microbiota of these young, relatively sexually inexperienced women. Women had consistent vaginal microbiota over time if lactobacilli were the dominant spp. present. Penile-vaginal sex did not alter the consistency of microbial communities but increased G.vaginalis clade diversity in young women with and without BV, suggesting sexual transmission of commensal and potentially pathogenic clades.

  20. Phylogenetic position of Sphaerospora testicularis and Latyspora scomberomori n. gen. n. sp. (Myxozoa) within the marine urinary clade

    Czech Academy of Sciences Publication Activity Database

    Bartošová, Pavla; Freeman, M. A.; Yokoyama, H.; Caffara, M.; Fiala, Ivan

    2011-01-01

    Roč. 138, č. 3 (2011), 381-393 ISSN 0031-1820 R&D Projects: GA AV ČR KJB600960701; GA ČR GD524/03/H133; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Myxosporea * Sphaerospora * Latyspora * Scomberomorus * Dicentrarchus * SSU rDNA * sutural line * marine urinary clade Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.961, year: 2011

  1. A new group in the Leptospirillum clade: cultivation-independent community genomics, proteomics and transcriptomics of the new species Leptospirillum group IV UBA BS.

    Energy Technology Data Exchange (ETDEWEB)

    Goltsman, Daniela [University of California, Berkeley; Dasari, Mauna [University of California, Berkeley; Thomas, BC [University of California, Berkeley; Shah, Manesh B [ORNL; Verberkmoes, Nathan C [ORNL; Hettich, Robert {Bob} L [ORNL; Banfield, Jillian F. [University of California, Berkeley

    2013-01-01

    Leptospirillum spp. are widespread members of acidophilic microbial communities that catalyze ferrous iron oxidation, thereby increasing sulfide mineral dissolution rates. These bacteria play important roles in environmental acidification and are harnessed for bioleaching-based metal recovery. Known members of the Leptospirillum clade of the Nitrospira phylum are Leptospirillum ferrooxidans (group I), Leptospirillum ferriphilum and Leptospirillum rubarum (group II), and Leptospirillum ferrodiazotrophum (group III). In the Richmond Mine acid mine drainage (AMD) system, biofilm formation is initiated by L. rubarum; L. ferrodiazotrophum appears in later developmental stages. Here we used community metagenomic data from unusual, thick floating biofilms to identify distinguishing metabolic traits in a rare and uncultivated community member, the new species Leptospirillum group IV UBA BS. These biofilms typically also contain a variety of Archaea, Actinobacteria, and a few other Leptospirillum spp. The Leptospirillum group IV UBA BS species shares 98% 16S rRNA sequence identity and 70% average amino acid identity between orthologs with its closest relative, L. ferrodiazotrophum. The presence of nitrogen fixation and reverse tricarboxylic acid (TCA) cycle proteins suggest an autotrophic metabolism similar to that of L. ferrodiazotrophum, while hydrogenase proteins suggest anaerobic metabolism. Community transcriptomic and proteomic analyses demonstrate expression of a multicopper oxidase unique to this species, as well as hydrogenases and core metabolic genes. Results suggest that the Leptospirillum group IV UBA BS species might play important roles in carbon fixation, nitrogen fixation, hydrogen metabolism, and iron oxidation in some acidic environments.

  2. Thermal regime and host clade, rather than geography, drive Symbiodinium and bacterial assemblages in the scleractinian coral Pocillopora damicornis sensu lato.

    Science.gov (United States)

    Brener-Raffalli, Kelly; Clerissi, Camille; Vidal-Dupiol, Jeremie; Adjeroud, Mehdi; Bonhomme, François; Pratlong, Marine; Aurelle, Didier; Mitta, Guillaume; Toulza, Eve

    2018-02-20

    Although the term holobiont has been popularized in corals with the advent of the hologenome theory of evolution, the underlying concepts are still a matter of debate. Indeed, the relative contribution of host and environment and especially thermal regime in shaping the microbial communities should be examined carefully to evaluate the potential role of symbionts for holobiont adaptation in the context of global changes. We used the sessile, long-lived, symbiotic and environmentally sensitive reef-building coral Pocillopora damicornis to address these issues. We sampled Pocillopora damicornis colonies corresponding to two different mitochondrial lineages in different geographic areas displaying different thermal regimes: Djibouti, French Polynesia, New Caledonia, and Taiwan. The community composition of bacteria and the algal endosymbiont Symbiodinium were characterized using high-throughput sequencing of 16S rRNA gene and internal transcribed spacer, ITS2, respectively. Bacterial microbiota was very diverse with high prevalence of Endozoicomonas, Arcobacter, and Acinetobacter in all samples. While Symbiodinium sub-clade C1 was dominant in Taiwan and New Caledonia, D1 was dominant in Djibouti and French Polynesia. Moreover, we also identified a high background diversity (i.e., with proportions world.

  3. Genes and Gene Therapy

    Science.gov (United States)

    ... correctly, a child can have a genetic disorder. Gene therapy is an experimental technique that uses genes to ... or prevent disease. The most common form of gene therapy involves inserting a normal gene to replace an ...

  4. Phylogenomic analyses of Crassiclitellata support major Northern and Southern Hemisphere clades and a Pangaean origin for earthworms.

    Science.gov (United States)

    Anderson, Frank E; Williams, Bronwyn W; Horn, Kevin M; Erséus, Christer; Halanych, Kenneth M; Santos, Scott R; James, Samuel W

    2017-05-30

    Earthworms (Crassiclitellata) are a diverse group of annelids of substantial ecological and economic importance. Earthworms are primarily terrestrial infaunal animals, and as such are probably rather poor natural dispersers. Therefore, the near global distribution of earthworms reflects an old and likely complex evolutionary history. Despite a long-standing interest in Crassiclitellata, relationships among and within major clades remain unresolved. In this study, we evaluate crassiclitellate phylogenetic relationships using 38 new transcriptomes in combination with publicly available transcriptome data. Our data include representatives of nearly all extant earthworm families and a representative of Moniligastridae, another terrestrial annelid group thought to be closely related to Crassiclitellata. We use a series of differentially filtered data matrices and analyses to examine the effects of data partitioning, missing data, compositional and branch-length heterogeneity, and outgroup inclusion. We recover a consistent, strongly supported ingroup topology irrespective of differences in methodology. The topology supports two major earthworm clades, each of which consists of a Northern Hemisphere subclade and a Southern Hemisphere subclade. Divergence time analysis results are concordant with the hypothesis that these north-south splits are the result of the breakup of the supercontinent Pangaea. These results support several recently proposed revisions to the classical understanding of earthworm phylogeny, reveal two major clades that seem to reflect Pangaean distributions, and raise new questions about earthworm evolutionary relationships.

  5. The Australasian frog family Ceratobatrachidae in China, Myanmar and Thailand: discovery of a new Himalayan forest frog clade

    Science.gov (United States)

    YAN, Fang; JIANG, Ke; WANG, Kai; JIN, Jie-Qiong; SUWANNAPOOM, Chatmongkon; LI, Cheng; Jens, V. VINDUM; Rafe, M. BROWN; CHE, Jing

    2016-01-01

    In an effort to study the systematic affinities and specieslevel phylogenetic relationships of the enigmatic anurans variably assigned to the genera Ingerana or Limnonectes (family Dicroglossidae), we collected new molecular sequence data for five species including four Himalayan taxa, Limnonectes xizangensis, Lim. medogensis, Lim. alpine, Ingerana borealis and one southeast Asian species, I. tasanae, and analyzed these together with data from previous studies involving other ostensibly related taxa. Our surprising results demonstrate unequivocally that Lim. xizangensis, Lim. medogensis and Lim. alpine form a strongly supported clade, the sister-group of the family Australasian forest frog family Ceratobatrachidae. This discovery requires an expansion of the definition of Ceratobatrachidae and represents the first record of this family in China. These three species are distinguished from the species of Ingerana and Limnonectes by the: (1) absence of interdigital webbing of the foot, (2) absence of terminal discs on fingers and toes, (3) absence of circumarginal grooves on the fingers and toes, and (4) absence of tarsal folds. Given their phylogenetic and morphological distinctiveness, we assign them to the oldest available generic name for this clade, Liurana Dubois 1987, and transfer Liurana from Dicroglossidae to the family Ceratobatrachidae. In contrast, Ingerana tasanae was found to be clustered with strong support with the recently described genus Alcalus (Ceratobatrachidae), a small clade of otherwise Sundaic species; this constitutes a new record of the family Ceratobatrachidae for Myanmar and Thailand. Finally, Ingerana borealis clustered with the "true" Ingerana (family Dicroglossidae), for which the type species is I. tenasserimensis. PMID:26828029

  6. The mystery of clade X: Orciraptor gen. nov. and Viridiraptor gen. nov. are highly specialised, algivorous amoeboflagellates (Glissomonadida, Cercozoa).

    Science.gov (United States)

    Hess, Sebastian; Melkonian, Michael

    2013-09-01

    In freshwater ecosystems a vast diversity of elusive protists exists that specifically feed on microalgae. Due to difficulties in isolation and long-term maintenance, most of these are still poorly known. In this study stable, bacteria-free cultures of several limnetic, algivorous amoeboflagellates were investigated by light microscopy and molecular phylogenetic analyses. All strains represent naked, biflagellate cells, either occurring as rigid flagellates or as surface-attached amoebae. They perforate cell walls of certain Zygnematophyceae and Chlorophyceae (Viridiplantae) and phagocytose algal cell contents. Time-lapse microscopy revealed the feeding behaviour, locomotional processes and life histories of the amoeboflagellates. Clear differences in cell morphology and food range specificity led to the description of two new, monotypic genera Orciraptor and Viridiraptor, which occupy similar, but distinct ecological niches in aquatic ecosystems as 'necrophytophagous' and 'parasitoid' protists, respectively. Molecular phylogenetic analyses based on 18S rDNA sequence data demonstrated that Orciraptor and Viridiraptor belonged to 'clade X' within the order Glissomonadida (Cercozoa, Rhizaria). In conclusion, we established the phenotypic identity of a clade, which until now was exclusively known from environmental sequences, and erect the new family Viridiraptoridae for 'clade X'. Its algivorous members are compared with other glissomonads and nomenclatural, methodological and ecological aspects of these novel 'raptorial' amoeboflagellates are discussed. Copyright © 2013 Elsevier GmbH. All rights reserved.

  7. The constancy of gene conservation across divergent bacterial orders

    Directory of Open Access Journals (Sweden)

    Ackermann Martin

    2009-01-01

    Full Text Available Abstract Background Orthologous genes are frequently presumed to perform similar functions. However, outside of model organisms, this is rarely tested. One means of inferring changes in function is if there are changes in the level of gene conservation and selective constraint. Here we compare levels of gene conservation across three bacterial groups to test for changes in gene functionality. Findings The level of gene conservation for different orthologous genes is highly correlated across clades, even for highly divergent groups of bacteria. These correlations do not arise from broad differences in gene functionality (e.g. informational genes vs. metabolic genes, but instead seem to result from very specific differences in gene function. Furthermore, these functional differences appear to be maintained over very long periods of time. Conclusion These results suggest that even over broad time scales, most bacterial genes are under a nearly constant level of purifying selection, and that bacterial evolution is thus dominated by selective and functional stasis.

  8. Advertisement call of Scinax camposseabrai (Bokermann, 1968) (Anura: Hylidae), with comments on the call of three species of the Scinax ruber clade.

    Science.gov (United States)

    Novaes, Gabriel; Zina, Juliana

    2016-02-25

    Scinax camposseabrai was allocated into the Scinax ruber clade by Caramaschi & Cardoso (2006) by overall similarities as snout not pointed, breeding in open areas, and an advertisement calls with multipulsed notes. This assumption about the call was based solely on an onomatopoeia provided by Bokermann (1968). Herein we provide a formal description of the advertisement call of S. camposseabrai and compare it with described calls of other S. ruber clade species. Additionally, we provide descriptions of the advertisement calls of three sympatric species of the S. ruber clade: S. eurydice (Bokermann), S. pachycrus (Miranda-Ribeiro) and S. cf. x-signatus.

  9. Revision of the Middle American clade of the ant genus Stenamma Westwood (Hymenoptera, Formicidae, Myrmicinae)

    Science.gov (United States)

    Branstetter, Michael G.

    2013-01-01

    Abstract Stenamma is a cryptic “leaf-litter” ant genus that occurs in mesic forest habitats throughout the Holarctic region, Central America, and part of northwestern South America (Colombia and Ecuador). The genus was thought to be restricted primarily to the temperate zone, but recent collecting efforts have uncovered a large radiation of Neotropical forms, which rival the Holarctic species in terms of morphological and behavioral diversity. By inferring a broad-scale molecular phylogeny of Stenamma, Branstetter (2012) showed that all Neotropical species belong to a diverse Middle American clade (MAC), and that this clade is sister to an almost completely geographically separated Holarctic clade (HOC). Here, the Middle American clade of Stenamma is revised to recognize 40 species, of which 33 are described as new. Included in the revision are a key to species based on the worker caste, and for each species where possible, descriptions and images of workers and queens, images of males, information on geographic distribution, descriptions of intraspecific variation, and notes on natural history. Several species groups are defined, but the majority of species remain unassigned due to a lack of diagnostic morphological character states for most molecular clades. The following species are redescribed: Stenamma alas Longino, Stenamma diversum Mann, Stenamma expolitum Smith, Stenamma felixi Mann, Stenamma huachucanum Smith, Stenamma manni Wheeler, and Stenamma schmidti Menozzi. The following are described as new: Stenamma andersoni sp. n., Stenamma atribellum sp. n., Stenamma brujita sp. n., Stenamma callipygium sp. n., Stenamma catracho sp. n., Stenamma connectum sp. n., Stenamma crypticum sp. n., Stenamma cusuco sp. n., Stenamma excisum sp. n., Stenamma expolitico sp. n., Stenamma hojarasca sp. n., Stenamma ignotum sp. n., Stenamma lagunum sp. n., Stenamma llama sp. n., Stenamma leptospinum sp. n., Stenamma lobinodus sp. n., Stenamma longinoi sp. n., Stenamma

  10. Empirical and Bayesian approaches to fossil-only divergence times: A study across three reptile clades.

    Science.gov (United States)

    Turner, Alan H; Pritchard, Adam C; Matzke, Nicholas J

    2017-01-01

    be correctly moderating the node-age estimate based on the limited morphological divergence. Topologies are generally similar across analyses, but BEAST trees for crocodyliforms differ when clades are deeply nested but contain very old taxa. It appears that the constant-rate sampling assumption of the BDSS tree prior influences topology inference by disfavoring long, unsampled branches.

  11. Empirical and Bayesian approaches to fossil-only divergence times: A study across three reptile clades.

    Directory of Open Access Journals (Sweden)

    Alan H Turner

    -clock model appears to be correctly moderating the node-age estimate based on the limited morphological divergence. Topologies are generally similar across analyses, but BEAST trees for crocodyliforms differ when clades are deeply nested but contain very old taxa. It appears that the constant-rate sampling assumption of the BDSS tree prior influences topology inference by disfavoring long, unsampled branches.

  12. Unique Phylogenetic Lineage Found in the Fusarium-like Clade after Re-examining BCCM/IHEM Fungal Culture Collection Material

    Science.gov (United States)

    De Cremer, Koen; Piérard, Denis; Hendrickx, Marijke

    2016-01-01

    Recently, the Fusarium genus has been narrowed based upon phylogenetic analyses and a Fusarium-like clade was adopted. The few species of the Fusarium-like clade were moved to new, re-installed or existing genera or provisionally retained as "Fusarium." Only a limited number of reference strains and DNA marker sequences are available for this clade and not much is known about its actual species diversity. Here, we report six strains, preserved by the Belgian fungal culture collection BCCM/IHEM as a Fusarium species, that belong to the Fusarium-like clade. They showed a slow growth and produced pionnotes, typical morphological characteristics of many Fusarium-like species. Multilocus sequencing with comparative sequence analyses in GenBank and phylogenetic analyses, using reference sequences of type material, confirmed that they were indeed member of the Fusarium-like clade. One strain was identified as "Fusarium" ciliatum whereas another strain was identified as Fusicolla merismoides. The four remaining strains were shown to represent a unique phylogenetic lineage in the Fusarium-like clade and were also found morphologically distinct from other members of the Fusarium-like clade. Based upon phylogenetic considerations, a new genus, Pseudofusicolla gen. nov., and a new species, Pseudofusicolla belgica sp. nov., were installed for this lineage. A formal description is provided in this study. Additional sampling will be required to gather isolates other than the historical strains presented in the present study as well as to further reveal the actual species diversity in the Fusarium-like clade. PMID:27790062

  13. Prevalence of Tobacco mosaic virus in Iran and Evolutionary Analyses of the Coat Protein Gene

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    Athar Alishiri

    2013-09-01

    Full Text Available The incidence and distribution of Tobacco mosaic virus (TMV and related tobamoviruses was determined using an enzyme-linked immunosorbent assay on 1,926 symptomatic horticultural crops and 107 asymptomatic weed samples collected from 78 highly infected fields in the major horticultural crop-producing areas in 17 provinces throughout Iran. The results were confirmed by host range studies and reverse transcription-polymerase chain reaction. The overall incidence of infection by these viruses in symptomatic plants was 11.3%. The coat protein (CP gene sequences of a number of isolates were determined and disclosed to be a high identity (up to 100% among the Iranian isolates. Phylogenetic analysis of all known TMV CP genes showed three clades on the basis of nucleotide sequences with all Iranian isolates distinctly clustered in clade II. Analysis using the complete CP amino acid sequence showed one clade with two subgroups, IA and IB, with Iranian isolates in both subgroups. The nucleotide diversity within each sub-group was very low, but higher between the two clades. No correlation was found between genetic distance and geographical origin or host species of isolation. Statistical analyses suggested a negative selection and demonstrated the occurrence of gene flow from the isolates in other clades to the Iranian population.

  14. Prototype of A/Duck/Sukoharjo/Bbvw-1428-9/2012 subtipe H5N1 clade 2.3.2 as vaccine on local duck

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    Risa Indriani

    2014-06-01

    Full Text Available A/Duck/Sukoharjo/Bbvw-1428-9/2012 virus subtipe H5N1 clade 2.3.2 as seed vaccine on local duck. AI H5N1 clade 2.3.2 vaccine containing 256 HAU per dose was formulated using adjuvant ISA 71VG Montanide ™. Six groups of one day old local duck were used in this study. Three groups (10 ducks per group were vaccinated and 3 groups (9 duck per group were served control. Vaccination was conducted when the duck were three weeks old of age using single dose. Three weeks after vaccination when the duck were challenged either with HPAI H5N1 clade 2.3.2, or HPAI H5N1 clade 2.1.3 virus at dose 106 EID50/ 0.1 ml by drops intranasaly. Result showed that vaccination produced 100% protection compared to unvaccinated ducks againt HPAI subtipe H5N1 clade 2.3.2, and 100% protection againt HPAI H5N1 clade 2.1.3 (A/ck/wj/Subang-29/2007 and A/ck/wj/Smi-Part/2006, while unvaccinated ducks showed virus shedding on day 3 post infection.

  15. Metabolic fluxes in the central carbon metabolism of Dinoroseobacter shibae and Phaeobacter gallaeciensis, two members of the marine Roseobacter clade

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    Rabus Ralf

    2009-09-01

    Full Text Available Abstract Background In the present work the central carbon metabolism of Dinoroseobacter shibae and Phaeobacter gallaeciensis was studied at the level of metabolic fluxes. These two strains belong to the marine Roseobacter clade, a dominant bacterial group in various marine habitats, and represent surface-associated, biofilm-forming growth (P. gallaeciensis and symbiotic growth with eukaryotic algae (D. shibae. Based on information from recently sequenced genomes, a rich repertoire of pathways has been identified in the carbon core metabolism of these organisms, but little is known about the actual contribution of the various reactions in vivo. Results Using 13C labelling techniques in specifically designed experiments, it could be shown that glucose-grown cells of D. shibae catabolise the carbon source exclusively via the Entner-Doudoroff pathway, whereas alternative routes of glycolysis and the pentose phosphate pathway are obviously utilised for anabolic purposes only. Enzyme assays confirmed this flux pattern and link the lack of glycolytic flux to the absence of phosphofructokinase activity. The previously suggested formation of phosphoenolpyruvate from pyruvate during mixotrophic CO2 assimilation was found to be inactive under the conditions studied. Moreover, it could be shown that pyruvate carboxylase is involved in CO2 assimilation and that the cyclic respiratory mode of the TCA cycle is utilised. Interestingly, the use of intracellular pathways was highly similar for P. gallaeciensis. Conclusion The present study reveals the first insight into pathway utilisation within the Roseobacter group. Fluxes through major intracellular pathways of the central carbon metabolism, which are closely linked to the various important traits found for the Roseobacter clade, could be determined. The close similarity of fluxes between the two physiologically rather different species might provide the first indication of more general key properties among

  16. New clade of enigmatic early archosaurs yields insights into early pseudosuchian phylogeny and the biogeography of the archosaur radiation.

    Science.gov (United States)

    Butler, Richard J; Sullivan, Corwin; Ezcurra, Martín D; Liu, Jun; Lecuona, Agustina; Sookias, Roland B

    2014-06-10

    The origin and early radiation of archosaurs and closely related taxa (Archosauriformes) during the Triassic was a critical event in the evolutionary history of tetrapods. This radiation led to the dinosaur-dominated ecosystems of the Jurassic and Cretaceous, and the high present-day archosaur diversity that includes around 10,000 bird and crocodylian species. The timing and dynamics of this evolutionary radiation are currently obscured by the poorly constrained phylogenetic positions of several key early archosauriform taxa, including several species from the Middle Triassic of Argentina (Gracilisuchus stipanicicorum) and China (Turfanosuchus dabanensis, Yonghesuchus sangbiensis). These species act as unstable 'wildcards' in morphological phylogenetic analyses, reducing phylogenetic resolution. We present new anatomical data for the type specimens of G. stipanicicorum, T. dabanensis, and Y. sangbiensis, and carry out a new morphological phylogenetic analysis of early archosaur relationships. Our results indicate that these three previously enigmatic taxa form a well-supported clade of Middle Triassic archosaurs that we refer to as Gracilisuchidae. Gracilisuchidae is placed basally within Suchia, among the pseudosuchian (crocodile-line) archosaurs. The approximately contemporaneous and morphologically similar G. stipanicicorum and Y. sangbiensis may be sister taxa within Gracilisuchidae. Our results provide increased resolution of the previously poorly constrained relationships of early archosaurs, with increased levels of phylogenetic support for several key early pseudosuchian clades. Moreover, they falsify previous hypotheses suggesting that T. dabanensis and Y. sangbiensis are not members of the archosaur crown group. The recognition of Gracilisuchidae provides further support for a rapid phylogenetic diversification of crown archosaurs by the Middle Triassic. The disjunct distribution of the gracilisuchid clade in China and Argentina demonstrates that early

  17. How to handle speciose clades? Mass taxon-sampling as a strategy towards illuminating the natural history of Campanula (Campanuloideae.

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    Guilhem Mansion

    Full Text Available BACKGROUND: Speciose clades usually harbor species with a broad spectrum of adaptive strategies and complex distribution patterns, and thus constitute ideal systems to disentangle biotic and abiotic causes underlying species diversification. The delimitation of such study systems to test evolutionary hypotheses is difficult because they often rely on artificial genus concepts as starting points. One of the most prominent examples is the bellflower genus Campanula with some 420 species, but up to 600 species when including all lineages to which Campanula is paraphyletic. We generated a large alignment of petD group II intron sequences to include more than 70% of described species as a reference. By comparison with partial data sets we could then assess the impact of selective taxon sampling strategies on phylogenetic reconstruction and subsequent evolutionary conclusions. METHODOLOGY/PRINCIPAL FINDINGS: Phylogenetic analyses based on maximum parsimony (PAUP, PRAP, Bayesian inference (MrBayes, and maximum likelihood (RAxML were first carried out on the large reference data set (D680. Parameters including tree topology, branch support, and age estimates, were then compared to those obtained from smaller data sets resulting from "classification-guided" (D088 and "phylogeny-guided sampling" (D101. Analyses of D088 failed to fully recover the phylogenetic diversity in Campanula, whereas D101 inferred significantly different branch support and age estimates. CONCLUSIONS/SIGNIFICANCE: A short genomic region with high phylogenetic utility allowed us to easily generate a comprehensive phylogenetic framework for the speciose Campanula clade. Our approach recovered 17 well-supported and circumscribed sub-lineages. Knowing these will be instrumental for developing more specific evolutionary hypotheses and guide future research, we highlight the predictive value of a mass taxon-sampling strategy as a first essential step towards illuminating the detailed

  18. Diversification Patterns of Lanternfishes Reveal Multiple Rate Shifts in a Critical Mesopelagic Clade Targeted for Human Exploitation.

    Science.gov (United States)

    Denton, John S S

    2018-03-19

    The mesopelagic (midwater) and deep-sea environments together comprise over 90% of the volume of the world ocean [1] and provide services that are only recently becoming recognized [2]. One of the most significant of these services relates to midwater fish biomass, recently estimated to be two orders of magnitude larger than the current worldwide fisheries catch [3, 4]. Calls to exploit midwater fish biomass have increased despite warnings about the unknown recovery potential of such organisms [2] and despite existing data suggesting that deep-sea fishes could be classified as endangered [5]. Here, to provide a null model for the respondability of midwater fishes, I use lanternfishes-which comprise the majority of worldwide midwater fish biomass [6]-to examine the diversification response of a critical midwater clade to oceanic changes over evolutionary timescales, including several extinction and turnover events. Using a time-calibrated molecular phylogeny based on seven autosomal protein-coding loci, with over 50% species sampling and three ingroup node calibrations, I show that lanternfishes exhibit a continuously increasing diversification rate, consistent with nonequilibrium speciation dynamics, and three major evolutionary rate shift locations with timing that is similar to those of marine clades in more well-known environments. These results suggest that lanternfish diversification patterns overlapped with major events in the physical partitioning of the ocean volume and that the clade has responded positively to a range of pre-Anthropocene extinction drivers [7]. However, lanternfish respondability to modern extinction drivers-habitat loss and overexploitation-is best addressed with populational and ecological data and remains largely unknown. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Molecular Signatures for the PVC Clade (Planctomycetes, Verrucomicrobia, Chlamydiae and Lentisphaerae of Bacteria Provide Insights into their Evolutionary Relationships

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    Radhey S. Gupta

    2012-09-01

    Full Text Available The PVC superphylum is an amalgamation of species from the phyla Planctomycetes, Verrucomicrobia and Chlamydiae, along with the Lentisphaerae, Poribacteria and two other candidate divisions. The diverse species of this superphylum lack any significant marker that differentiates them from other bacteria. Recently, genome sequences for 37 species covering all of the main PVC groups of bacteria have become available. We have used these sequences to construct a phylogenetic tree based upon concatenated sequences for 16 proteins and identify molecular signatures in protein sequences that are specific for the species from these phyla or those providing molecular links among them. Of the useful molecular markers identified in the present work, 6 conserved signature indels (CSIs in the proteins Cyt c oxidase, UvrD helicase, urease and a helicase-domain containing protein are specific for the species from the Verrucomicrobia phylum; three other CSIs in an ABC transporter protein, cobyrinic acid ac-diamide synthase and SpoVG protein are specific for the Planctomycetes species. Additionally, a 3 aa insert in the RpoB protein is uniquely present in all sequenced Chlamydiae, Verrucomicrobia and Lentisphaerae species, providing evidence for the shared ancestry of the species from these three phyla. Lastly, we have also identified a conserved protein of unknown function that is exclusively found in all sequenced species from the phyla Chlamydiae, Verrucomicrobia, Lentisphaerae and Planctomycetes suggesting a specific linkage among them. The absence of this protein in Poribacteria, which branches separately from other members of the PVC clade, indicates that it is not specifically related to the PVC clade of bacteria. The molecular markers described here in addition to clarifying the evolutionary relationships among the PVC clade of bacteria also provide novel tools for their identification and for genetic and biochemical studies on these organisms.

  20. Dynamic of H5N1 virus in Cambodia and emergence of a novel endemic sub-clade.

    Science.gov (United States)

    Sorn, San; Sok, Touch; Ly, Sovann; Rith, Sareth; Tung, Nguyen; Viari, Alain; Gavotte, Laurent; Holl, Davun; Seng, Heng; Asgari, Nima; Richner, Beat; Laurent, Denis; Chea, Nora; Duong, Veasna; Toyoda, Tetsuya; Yasuda, Chadwick Y; Kitsutani, Paul; Zhou, Paul; Bing, Sun; Deubel, Vincent; Donis, Ruben; Frutos, Roger; Buchy, Philippe

    2013-04-01

    In Cambodia, the first detection of HPAI H5N1 virus in birds occurred in January 2004 and since then there have been 33 outbreaks in poultry while 21 human cases were reported. The origin and dynamics of these epizootics in Cambodia remain unclear. In this work we used a range of bioinformatics methods to analyze the Cambodian virus sequences together with those from neighboring countries. Six HA lineages belonging to clades 1 and 1.1 were identified since 2004. Lineage 1 shares an ancestor with viruses from Thailand and disappeared after 2005, to be replaced by lineage 2 originating from Vietnam and then by lineage 3. The highly adapted lineage 4 was seen only in Cambodia. Lineage 5 is circulating both in Vietnam and Cambodia since 2008 and was probably introduced in Cambodia through unregistered transboundary poultry trade. Lineage 6 is endemic to Cambodia since 2010 and could be classified as a new clade according to WHO/OIE/FAO criteria for H5N1 virus nomenclature. We propose to name it clade 1.1A. There is a direct filiation of lineages 2 to 6 with a temporal evolution and geographic differentiation for lineages 4 and 6. By the end of 2011, two lineages, i.e. lineages 5 and 6, with different transmission paths cocirculate in Cambodia. The presence of lineage 6 only in Cambodia suggests the existence of a transmission specific to this country whereas the presence of lineage 5 in both Cambodia and Vietnam indicates a distinct way of circulation of infected poultry. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. How to Handle Speciose Clades? Mass Taxon-Sampling as a Strategy towards Illuminating the Natural History of Campanula (Campanuloideae)

    Science.gov (United States)

    Mansion, Guilhem; Parolly, Gerald; Crowl, Andrew A.; Mavrodiev, Evgeny; Cellinese, Nico; Oganesian, Marine; Fraunhofer, Katharina; Kamari, Georgia; Phitos, Dimitrios; Haberle, Rosemarie; Akaydin, Galip; Ikinci, Nursel; Raus, Thomas; Borsch, Thomas

    2012-01-01

    Background Speciose clades usually harbor species with a broad spectrum of adaptive strategies and complex distribution patterns, and thus constitute ideal systems to disentangle biotic and abiotic causes underlying species diversification. The delimitation of such study systems to test evolutionary hypotheses is difficult because they often rely on artificial genus concepts as starting points. One of the most prominent examples is the bellflower genus Campanula with some 420 species, but up to 600 species when including all lineages to which Campanula is paraphyletic. We generated a large alignment of petD group II intron sequences to include more than 70% of described species as a reference. By comparison with partial data sets we could then assess the impact of selective taxon sampling strategies on phylogenetic reconstruction and subsequent evolutionary conclusions. Methodology/Principal Findings Phylogenetic analyses based on maximum parsimony (PAUP, PRAP), Bayesian inference (MrBayes), and maximum likelihood (RAxML) were first carried out on the large reference data set (D680). Parameters including tree topology, branch support, and age estimates, were then compared to those obtained from smaller data sets resulting from “classification-guided” (D088) and “phylogeny-guided sampling” (D101). Analyses of D088 failed to fully recover the phylogenetic diversity in Campanula, whereas D101 inferred significantly different branch support and age estimates. Conclusions/Significance A short genomic region with high phylogenetic utility allowed us to easily generate a comprehensive phylogenetic framework for the speciose Campanula clade. Our approach recovered 17 well-supported and circumscribed sub-lineages. Knowing these will be instrumental for developing more specific evolutionary hypotheses and guide future research, we highlight the predictive value of a mass taxon-sampling strategy as a first essential step towards illuminating the detailed evolutionary

  2. Systematics of Plant-Pathogenic and Related Streptomyces Species Based on Phylogenetic Analyses of Multiple Gene Loci

    Science.gov (United States)

    The 10 species of Streptomyces implicated as the etiological agents in scab disease of potatoes or soft rot disease of sweet potatoes are distributed among 7 different phylogenetic clades in analyses based on 16S rRNA gene sequences, but high sequence similarity of this gene among Streptomyces speci...

  3. A novel strategy for efficient production of anti-V3 human scFvs against HIV-1 clade C

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    Kumar Rajesh

    2012-11-01

    Full Text Available Abstract Background Production of human monoclonal antibodies that exhibit broadly neutralizing activity is needed for preventing HIV-1 infection, however only a few such antibodies have been generated till date. Isolation of antibodies by the hybridoma technology is a cumbersome process with fewer yields. Further, the loss of unstable or slowly growing clones which may have unique binding specificities often occurs during cloning and propagation and the strongly positive clones are often lost. This has been avoided by the process described in this paper, wherein, by combining the strategy of EBV transformation and recombinant DNA technology, we constructed human single chain variable fragments (scFvs against the third variable region (V3 of the clade C HIV-1 envelope. Results An antigen specific phage library of 7000 clones was constructed from the enriched V3- positive antibody secreting EBV transformed cells. By ligation of the digested scFv DNA into phagemid vector and bio panning against the HIV-1 consensus C and B V3 peptides followed by random selection of 40 clones, we identified 15 clones that showed V3 reactivity in phage ELISA. DNA fingerprinting analysis and sequencing showed that 13 out of the 15 clones were distinct. Expression of the positive clones was tested by SDS-PAGE and Western blot. All the 13 anti-V3 scFvs showed cross-reactivity against both the clade C and B V3 peptides and did not show any reactivity against other unrelated peptides in ELISA. Preliminary neutralization assays indicated varying degrees of neutralization of clade C and B viruses. EBV transformation, followed by antigen selection of lines to identify specific binders, enabled the selection of phage from un-cloned lines for scFv generation, thus avoiding the problems of hybridoma technology. Moreover, as the clones were pretested for antigen binding, a comparatively small library sufficed for the selection of a considerable number of unique antigen binding

  4. Molecular Phylogenetics of the Serranid Subfamily Epinephelinae: Speciation and Biogeography in a Nearshore Marine Fish Clade

    OpenAIRE

    Craig, Matthew T,

    2005-01-01

    The processes that shape present day distributions of marine organisms have remained a central topic in evolutionary biology, conservation biology, and ecology. In this thesis, genetic data from mitochondrial and nuclear genes were used to create a phylogenetic hypothesis for the groupers of the subfamily Epinephelinae as a means of evaluating the current taxonomy of the group and the geography of speciation in marine organisms. The molecular phylogenetic hypothesis presented in Chap...

  5. A novel methanotroph in the genus Methylomonas that contains a distinct clade of soluble methane monooxygenase.

    Science.gov (United States)

    Nguyen, Ngoc-Loi; Yu, Woon-Jong; Yang, Hye-Young; Kim, Jong-Geol; Jung, Man-Young; Park, Soo-Je; Roh, Seong-Woon; Rhee, Sung-Keun

    2017-10-01

    Aerobic methane oxidation is a key process in the global carbon cycle that acts as a major sink of methane. In this study, we describe a novel methanotroph designated EMGL16-1 that was isolated from a freshwater lake using the floating filter culture technique. Based on a phylogenetic analysis of 16S rRNA gene sequences, the isolate was found to be closely related to the genus Methylomonas in the family Methylococcaceae of the class Gammaproteobacteria with 94.2-97.4% 16S rRNA gene similarity to Methylomonas type strains. Comparison of chemotaxonomic and physiological properties further suggested that strain EMGL16-1 was taxonomically distinct from other species in the genus Methylomonas. The isolate was versatile in utilizing nitrogen sources such as molecular nitrogen, nitrate, nitrite, urea, and ammonium. The genes coding for subunit of the particulate form methane monooxygenase (pmoA), soluble methane monooxygenase (mmoX), and methanol dehydrogenase (mxaF) were detected in strain EMGL16-1. Phylogenetic analysis of mmoX indicated that mmoX of strain EMGL16-1 is distinct from those of other strains in the genus Methylomonas. This isolate probably represents a novel species in the genus. Our study provides new insights into the diversity of species in the genus Methylomonas and their environmental adaptations.

  6. Atomic force microscopy imaging reveals the formation of ASIC/ENaC cross-clade ion channels

    International Nuclear Information System (INIS)

    Jeggle, Pia; Smith, Ewan St. J.; Stewart, Andrew P.; Haerteis, Silke; Korbmacher, Christoph; Edwardson, J. Michael

    2015-01-01

    ASIC and ENaC are co-expressed in various cell types, and there is evidence for a close association between them. Here, we used atomic force microscopy (AFM) to determine whether ASIC1a and ENaC subunits are able to form cross-clade hybrid ion channels. ASIC1a and ENaC could be co-isolated from detergent extracts of tsA 201 cells co-expressing the two subunits. Isolated proteins were incubated with antibodies against ENaC and Fab fragments against ASIC1a. AFM imaging revealed proteins that were decorated by both an antibody and a Fab fragment with an angle of ∼120° between them, indicating the formation of ASIC1a/ENaC heterotrimers. - Highlights: • There is evidence for a close association between ASIC and ENaC. • We used AFM to test whether ASIC1a and ENaC subunits form cross-clade ion channels. • Isolated proteins were incubated with subunit-specific antibodies and Fab fragments. • Some proteins were doubly decorated at ∼120° by an antibody and a Fab fragment. • Our results indicate the formation of ASIC1a/ENaC heterotrimers

  7. New insights on the phylogenetic relationships among the traditional Philodendron subgenera and the other groups of the Homalomena clade (Araceae).

    Science.gov (United States)

    Vasconcelos, Santelmo; Soares, Maria de Lourdes; Sakuragui, Cássia M; Croat, Thomas B; Oliveira, Guilherme; Benko-Iseppon, Ana M

    2018-05-19

    Philodendron (Araceae) is one of the largest Neotropical plant genera, with approximately 500 species and at least 1000 species predicted. There is a considerable ecological diversity in the group, although most species occur in the humid forests of tropical America. Despite being relatively well-studied in taxonomic analyses, the relationships among the traditional morphological groups of the genus are not well-established, mainly regarding the three traditional subgenera, referred here as Philodendron sensu lato (s.l.), P. subg. Pteromischum, P. subg. Philodendron and P. subg. Meconostigma, which was recently recognized as a separate genus, Thaumatophyllum. Therefore, the present work evaluates the phylogenetic position and the monophyly of Philodendron s.l. and its three main subdivisions, and the sister groups within the Homalomena clade, which also includes the Neotropical genus Adelonema, the two Asian genera Homalomena and Furtadoa, and the two African genera Cercestis and Culcasia, by means of molecular phylogenetic approaches including chloroplast DNA (atpF-atpH, rpl32-trnL, trnQ-5'-rps16 and trnV-ndhC) and nuclear (ITS2) markers. The monophyly of Philodendron s.l. and its three lineages is confirmed and our analyses corroborate previous morphologic data indicating Thaumatophyllum as sister to the clade formed by P. subg. Pteromischum and P. subg. Philodendron. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Evolution of extreme ontogenetic allometric diversity and heterochrony in pythons, a clade of giant and dwarf snakes.

    Science.gov (United States)

    Esquerré, Damien; Sherratt, Emma; Keogh, J Scott

    2017-12-01

    Ontogenetic allometry, how species change with size through their lives, and heterochony, a decoupling between shape, size, and age, are major contributors to biological diversity. However, macroevolutionary allometric and heterochronic trends remain poorly understood because previous studies have focused on small groups of closely related species. Here, we focus on testing hypotheses about the evolution of allometry and how allometry and heterochrony drive morphological diversification at the level of an entire species-rich and diverse clade. Pythons are a useful system due to their remarkably diverse and well-adapted phenotypes and extreme size disparity. We collected detailed phenotype data on 40 of the 44 species of python from 1191 specimens. We used a suite of analyses to test for shifts in allometric trajectories that modify morphological diversity. Heterochrony is the main driver of initial divergence within python clades, and shifts in the slopes of allometric trajectories make exploration of novel phenotypes possible later in divergence history. We found that allometric coefficients are highly evolvable and there is an association between ontogenetic allometry and ecology, suggesting that allometry is both labile and adaptive rather than a constraint on possible phenotypes. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  9. Coexistence of two clades of enterovirus D68 in pediatric Swedish patients in the summer and fall of 2014.

    Science.gov (United States)

    Dyrdak, Robert; Rotzén-Östlund, Maria; Samuelson, Agneta; Eriksson, Margareta; Albert, Jan

    2015-01-01

    In 2014, an outbreak of enterovirus D68 (EV-D68) was observed in North America, with cases of severe respiratory illness and a possible etiological link to cases of acute flaccid paralysis. EV-D68 has also been reported from European countries, but no data from Sweden are available. This study investigated respiratory specimens collected during July-October 2014 from 30 Swedish children aged 0-9 years who were positive for enterovirus and/or rhinovirus in routine clinical PCR. Seven samples were typed as EV-D68 by VP4/VP2 sequencing. Two genetically distinct EV-D68 variants coexisted. Six viruses belonged to clade B, the variant involved in the North American outbreak, and one virus belonged to clade A. Respiratory illness was the major symptom among EV-D68 infected patients and all fully recovered. This is the first report of EV-D68 in Sweden. Considering the current epidemiological situation, genotyping and specific EV-D68 testing should be considered in patients with severe respiratory illness who test positive for enterovirus or rhinovirus in routine diagnostics.

  10. Atomic force microscopy imaging reveals the formation of ASIC/ENaC cross-clade ion channels

    Energy Technology Data Exchange (ETDEWEB)

    Jeggle, Pia; Smith, Ewan St. J.; Stewart, Andrew P. [Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD (United Kingdom); Haerteis, Silke; Korbmacher, Christoph [Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstrasse 6, 91054 Erlangen (Germany); Edwardson, J. Michael, E-mail: jme1000@cam.ac.uk [Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD (United Kingdom)

    2015-08-14

    ASIC and ENaC are co-expressed in various cell types, and there is evidence for a close association between them. Here, we used atomic force microscopy (AFM) to determine whether ASIC1a and ENaC subunits are able to form cross-clade hybrid ion channels. ASIC1a and ENaC could be co-isolated from detergent extracts of tsA 201 cells co-expressing the two subunits. Isolated proteins were incubated with antibodies against ENaC and Fab fragments against ASIC1a. AFM imaging revealed proteins that were decorated by both an antibody and a Fab fragment with an angle of ∼120° between them, indicating the formation of ASIC1a/ENaC heterotrimers. - Highlights: • There is evidence for a close association between ASIC and ENaC. • We used AFM to test whether ASIC1a and ENaC subunits form cross-clade ion channels. • Isolated proteins were incubated with subunit-specific antibodies and Fab fragments. • Some proteins were doubly decorated at ∼120° by an antibody and a Fab fragment. • Our results indicate the formation of ASIC1a/ENaC heterotrimers.

  11. Does the colonization of new biogeographic regions influence the diversification and accumulation of clade richness among the Corvides (Aves: Passeriformes)?

    Science.gov (United States)

    Kennedy, Jonathan D; Borregaard, Michael K; Jønsson, Knud A; Holt, Ben; Fjeldså, Jon; Rahbek, Carsten

    2017-01-01

    Regional variation in clade richness can be vast, reflecting differences in the dynamics of historical dispersal and diversification among lineages. Although it has been proposed that dispersal into new biogeographic regions may facilitate diversification, to date there has been limited assessment of the importance of this process in the generation, and maintenance, of broad-scale biodiversity gradients. To address this issue, we analytically derive biogeographic regions for a global radiation of passerine birds (the Corvides, c. 790 species) that are highly variable in the geographic and taxonomic distribution of species. Subsequently, we determine rates of historical dispersal between regions, the dynamics of diversification following regional colonization, and spatial variation in the distribution of species that differ in their rates of lineage diversification. The results of these analyses reveal spatiotemporal differences in the build-up of lineages across regions. The number of regions occupied and the rate of transition between regions both predict family richness well, indicating that the accumulation of high clade richness is associated with repeated expansion into new geographic areas. However, only the largest family (the Corvidae) had significantly heightened rates of both speciation and regional transition, implying that repeated regional colonization is not a general mechanism promoting lineage diversification among the Corvides. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  12. Comparison of Monkeypox Virus Clade Kinetics and Pathology within the Prairie Dog Animal Model Using a Serial Sacrifice Study Design

    Directory of Open Access Journals (Sweden)

    Christina L. Hutson

    2015-01-01

    Full Text Available Monkeypox virus (MPXV infection of the prairie dog is valuable to studying systemic orthopoxvirus disease. To further characterize differences in MPXV clade pathogenesis, groups of prairie dogs were intranasally infected (8×103 p.f.u. with Congo Basin (CB or West African (WA MPXV, and 28 tissues were harvested on days 2, 4, 6, 9, 12, 17, and 24 postinfection. Samples were evaluated for the presence of virus and gross and microscopic lesions. Virus was recovered from nasal mucosa, oropharyngeal lymph nodes, and spleen earlier in CB challenged animals (day 4 than WA challenged animals (day 6. For both groups, primary viremia (indicated by viral DNA was seen on days 6–9 through day 17. CB MPXV spread more rapidly, accumulated to greater levels, and caused greater morbidity in animals compared to WA MPXV. Histopathology and immunohistochemistry (IHC findings, however, were similar. Two animals that succumbed to disease demonstrated abundant viral antigen in all organs tested, except for brain. Dual-IHC staining of select liver and spleen sections showed that apoptotic cells (identified by TUNEL tended to colocalize with poxvirus antigen. Interestingly splenocytes were labelled positive for apoptosis more often than hepatocytes in both MPXV groups. These findings allow for further characterization of differences between MPXV clade pathogenesis, including identifying sites that are important during early viral replication and cellular response to viral infection.

  13. "cART intensification by the HIV-1 Tat B clade vaccine: progress to phase III efficacy studies".

    Science.gov (United States)

    Cafaro, Aurelio; Sgadari, Cecilia; Picconi, Orietta; Tripiciano, Antonella; Moretti, Sonia; Francavilla, Vittorio; Pavone Cossut, Maria Rosaria; Buttò, Stefano; Cozzone, Giovanni; Ensoli, Fabrizio; Monini, Paolo; Ensoli, Barbara

    2018-02-01

    In spite of its success at suppressing HIV replication, combination antiretroviral therapy (cART) only partially reduces immune dysregulation and loss of immune functions. These cART-unmet needs appear to be due to persistent virus replication and cell-to-cell transmission in reservoirs, and are causes of increased patients' morbidity and mortality. Up to now, therapeutic interventions aimed at cART-intensification by attacking the virus reservoir have failed. Areas covered: We briefly review the rationale and clinical development of Tat therapeutic vaccine in cART-treated subjects in Italy and South Africa (SA). Vaccination with clade-B Tat induced cross-clade neutralizing antibodies, immune restoration, including CD4 + T cell increase particularly in low immunological responders, and reduction of proviral DNA. Phase III efficacy trials in SA are planned both in adult and pediatric populations. Expert commentary: We propose the Tat therapeutic vaccine as a pathogenesis-driven intervention that effectively intensifies cART and may lead to a functional cure and provide new perspectives for prevention and virus eradication strategies.

  14. Development and characterization of 79 nuclear markers amplifying in viviparous and oviparous clades of the European common lizard.

    Science.gov (United States)

    Horreo, J L; Peláez, M L; Suárez, T; Fitze, P S

    2018-02-01

    The European common lizard (Zootoca vivipara) is a widely distributed species across Europe and Asia exhibiting two reproductive modes (oviparity/viviparity), six major lineages and several sublineages. It has been used to tackle a large variety of research questions, nevertheless, few nuclear DNA sequence markers have been developed for this species. Here we developed 79 new nuclear DNA sequence markers using a clonation protocol. These markers were amplified in several oviparous and viviparous specimens including samples of all extant clades, to test the amplification success and their diversity. 49.4% of the markers were polymorphic and of those, 51.3% amplified in all and 94.9% amplified in 5-7 of the extant Z. vivipara clades. These new markers will be very useful for the study of the population structure, population dynamics, and micro/macro evolution of Z. vivipara. Cross-species amplification in four lizard species (Psammodromus edwardsianus, Podarcis muralis, Lacerta bilineata, and Takydromus sexlineatus) was positive in several of the markers, and six makers amplified in all five species. The large genetic distance between P. edwardsianus and Z. vivipara further suggests that these markers may as well be employed in many other species.

  15. Phylogenetic Relationships of Pseudorasbora, Pseudopungtungia, and Pungtungia (Teleostei; Cypriniformes; Gobioninae Inferred from Multiple Nuclear Gene Sequences

    Directory of Open Access Journals (Sweden)

    Keun-Yong Kim

    2013-01-01

    Full Text Available Gobionine species belonging to the genera Pseudorasbora, Pseudopungtungia, and Pungtungia (Teleostei; Cypriniformes; Cyprinidae have been heavily studied because of problems on taxonomy, threats of extinction, invasion, and human health. Nucleotide sequences of three nuclear genes, that is, recombination activating protein gene 1 (rag1, recombination activating gene 2 (rag2, and early growth response 1 gene (egr1, from Pseudorasbora, Pseudopungtungia, and Pungtungia species residing in China, Japan, and Korea, were analyzed to elucidate their intergeneric and interspecific phylogenetic relationships. In the phylogenetic tree inferred from their multiple gene sequences, Pseudorasbora, Pseudopungtungia and Pungtungia species ramified into three phylogenetically distinct clades; the “tenuicorpa” clade composed of Pseudopungtungia tenuicorpa, the “parva” clade composed of all Pseudorasbora species/subspecies, and the “herzi” clade composed of Pseudopungtungia nigra, and Pungtungia herzi. The genus Pseudorasbora was recovered as monophyletic, while the genus Pseudopungtungia was recovered as polyphyletic. Our phylogenetic result implies the unstable taxonomic status of the genus Pseudopungtungia.

  16. Phylogenetic signal detection from an ancient rapid radiation: Effects of noise reduction, long-branch attraction, and model selection in crown clade Apocynaceae.

    Science.gov (United States)

    Straub, Shannon C K; Moore, Michael J; Soltis, Pamela S; Soltis, Douglas E; Liston, Aaron; Livshultz, Tatyana

    2014-11-01

    Crown clade Apocynaceae comprise seven primary lineages of lianas, shrubs, and herbs with a diversity of pollen aggregation morphologies including monads, tetrads, and pollinia, making them an ideal group for investigating the evolution and function of pollen packaging. Traditional molecular systematic approaches utilizing small amounts of sequence data have failed to resolve relationships along the spine of the crown clade, a likely ancient rapid radiation. The previous best estimate of the phylogeny was a five-way polytomy, leaving ambiguous the homology of aggregated pollen in two major lineages, the Periplocoideae, which possess pollen tetrads, and the milkweeds (Secamonoideae plus Asclepiadoideae), which possess pollinia. To assess whether greatly increased character sampling would resolve these relationships, a plastome sequence data matrix was assembled for 13 taxa of Apocynaceae, including nine newly generated complete plastomes, one partial new plastome, and three previously reported plastomes, collectively representing all primary crown clade lineages and outgroups. The effects of phylogenetic noise, long-branch attraction, and model selection (linked versus unlinked branch lengths among data partitions) were evaluated in a hypothesis-testing framework based on Shimodaira-Hasegawa tests. Discrimination among alternative crown clade resolutions was affected by all three factors. Exclusion of the noisiest alignment positions and topologies influenced by long-branch attraction resulted in a trichotomy along the spine of the crown clade consisting of Rhabdadenia+the Asian clade, Baisseeae+milkweeds, and Periplocoideae+the New World clade. Parsimony reconstruction on all optimal topologies after noise exclusion unambiguously supports parallel evolution of aggregated pollen in Periplocoideae (tetrads) and milkweeds (pollinia). Our phylogenomic approach has greatly advanced the resolution of one of the most perplexing radiations in Apocynaceae, providing the

  17. Human Clade 2.3.4.4 A/H5N6 Influenza Virus Lacks Mammalian Adaptation Markers and Does Not Transmit via the Airborne Route between Ferrets.

    Science.gov (United States)

    Herfst, Sander; Mok, Chris K P; van den Brand, Judith M A; van der Vliet, Stefan; Rosu, Miruna E; Spronken, Monique I; Yang, Zifeng; de Meulder, Dennis; Lexmond, Pascal; Bestebroer, Theo M; Peiris, J S Malik; Fouchier, Ron A M; Richard, Mathilde

    2018-01-01

    Since their emergence in 1997, A/H5N1 influenza viruses of the A/goose/Guangdong/1/96 lineage have diversified in multiple genetic and antigenic clades upon continued circulation in poultry in several countries in Eurasia and Africa. Since 2009, reassortant viruses carrying clade 2.3.4.4 hemagglutinin (HA) and internal and neuraminidase (NA) genes of influenza A viruses of different avian origin have been detected, yielding various HA-NA combinations, such as A/H5N1, A/H5N2, A/H5N3, A/H5N5, A/H5N6, and A/H5N8. Previous studies reported on the low pathogenicity and lack of airborne transmission of A/H5N2 and A/H5N8 viruses in the ferret model. However, although A/H5N6 viruses are the only clade 2.3.4.4 viruses that crossed the species barrier and infected humans, the risk they pose for human health remains poorly characterized. Here, the characterization of A/H5N6 A/Guangzhou/39715/2014 virus in vitro and in ferrets is described. This A/H5N6 virus possessed high polymerase activity, mediated by the E627K substitution in the PB2 protein, which corresponds to only one biological trait out of the three that were previously shown to confer airborne transmissibility to A/H5N1 viruses between ferrets. This might explain its lack of airborne transmission between ferrets. After intranasal inoculation, A/H5N6 virus replicated to high titers in the respiratory tracts of ferrets and was excreted for at least 6 days. Moreover, A/H5N6 virus caused severe pneumonia in ferrets upon intratracheal inoculation. Thus, A/H5N6 virus causes a more severe disease in ferrets than previously investigated clade 2.3.4.4 viruses, but our results demonstrate that the risk from airborne spread is currently low. IMPORTANCE Avian influenza A viruses are a threat to human health, as they cross the species barrier and infect humans occasionally, often with severe outcome. The antigenic and genetic diversity of A/H5 viruses from the A/goose/Guangdong/1/96 lineage is increasing, due to continued

  18. Phaeobacter inhibens from the Roseobacter clade has an environmental niche as a surface colonizer in harbors

    DEFF Research Database (Denmark)

    Gram, Lone; Rasmussen, Bastian Barker; Wemheuer, Bernd

    2015-01-01

    in the environment is to date unknown. Here, we report on the repeated isolation of Phaeobacter inhibens strains from a marine environment (harbors) not related to aquaculture. Based on phenotype and 16S rRNA gene sequence similarity, a total of 64 P. inhibens strains were identified from 35 samples (eukaryotic...... and used for amplification of 16S rRNA. P. inhibens was detected in five of these samples, all of which were biofilm samples, by pyrotag-sequencing at a prevalence of 0.02–0.68% of the prokaryotic community. The results indicated that P. inhibens had a niche in biofilms of fouled surfaces in harbor areas...

  19. Phylogenomics and comparative genomic studies delineate six main clades within the family Enterobacteriaceae and support the reclassification of several polyphyletic members of the family.

    Science.gov (United States)

    Alnajar, Seema; Gupta, Radhey S

    2017-10-01

    The family Enterobacteriaceae harbors many important pathogens, however it has proven difficult to reliably distinguish different members of this family or discern their interrelationships. To understand the interrelationships among the Enterobacteriaceae species, we have constructed two comprehensive phylogenetic trees for 78 genome-sequenced Enterobacteriaceae species based on 2487 core genome proteins, and another set of 118 conserved proteins. The genome sequences of Enterobacteriaceae species were also analyzed for genetic relatedness based on average amino acid identity and 16S rRNA sequence similarity. In parallel, comparative genomic studies on protein sequences from the Enterobacteriaceae have identified 88 molecular markers in the form of conserved signature indels (CSIs) that are uniquely shared by specific members of the family. All of these multiple lines of investigations provide consistent evidence that most of the species/genera within the family can be assigned to 6 different subfamily level clades which are designated as the "Escherichia clade", "Klebsiella clade", "Enterobacter clade", "Kosakonia clade", "Cronobacter clade" and "Cedecea clade". The members of the six described clades, in addition to their distinct branching in phylogenetic trees, can now be reliably demarcated in molecular terms on the basis of multiple identified CSIs that are exclusively shared by the group members. Several additional CSIs identified in this work that are either specific for individual genera (viz. Kosakonia, Kluyvera and Escherichia-Shigella), or are present at various taxonomic depths, offer information regarding the interrelationships among the different clades. The described molecular markers provide novel means for diagnostic as well as genetic and biochemical studies on the Enterobacteriaceae species and for resolving the polyphyly of its several genera viz. Escherichia, Enterobacter and Kluyvera. On the bases of our results, we are proposing the

  20. Molecular-based rapid inventories of sympatric diversity: a comparison of DNA barcode clustering methods applied to geography-based vs clade-based sampling of amphibians.

    Science.gov (United States)

    Paz, Andrea; Crawford, Andrew J

    2012-11-01

    Molecular markers offer a universal source of data for quantifying biodiversity. DNA barcoding uses a standardized genetic marker and a curated reference database to identify known species and to reveal cryptic diversity within wellsampled clades. Rapid biological inventories, e.g. rapid assessment programs (RAPs), unlike most barcoding campaigns, are focused on particular geographic localities rather than on clades. Because of the potentially sparse phylogenetic sampling, the addition of DNA barcoding to RAPs may present a greater challenge for the identification of named species or for revealing cryptic diversity. In this article we evaluate the use of DNA barcoding for quantifying lineage diversity within a single sampling site as compared to clade-based sampling, and present examples from amphibians. We compared algorithms for identifying DNA barcode clusters (e.g. species, cryptic species or Evolutionary Significant Units) using previously published DNA barcode data obtained from geography-based sampling at a site in Central Panama, and from clade-based sampling in Madagascar. We found that clustering algorithms based on genetic distance performed similarly on sympatric as well as clade-based barcode data, while a promising coalescent-based method performed poorly on sympatric data. The various clustering algorithms were also compared in terms of speed and software implementation. Although each method has its shortcomings in certain contexts, we recommend the use of the ABGD method, which not only performs fairly well under either sampling method, but does so in a few seconds and with a user-friendly Web interface.

  1. The Transcriptomes of Xiphinema index and Longidorus elongatus Suggest Independent Acquisition of Some Plant Parasitism Genes by Horizontal Gene Transfer in Early-Branching Nematodes

    Directory of Open Access Journals (Sweden)

    Etienne G.J. Danchin

    2017-10-01

    Full Text Available Nematodes have evolved the ability to parasitize plants on at least four independent occasions, with plant parasites present in Clades 1, 2, 10 and 12 of the phylum. In the case of Clades 10 and 12, horizontal gene transfer of plant cell wall degrading enzymes from bacteria and fungi has been implicated in the evolution of plant parasitism. We have used ribonucleic acid sequencing (RNAseq to generate reference transcriptomes for two economically important nematode species, Xiphinema index and Longidorus elongatus, representative of two genera within the early-branching Clade 2 of the phylum Nematoda. We used a transcriptome-wide analysis to identify putative horizontal gene transfer events. This represents the first in-depth transcriptome analysis from any plant-parasitic nematode of this clade. For each species, we assembled ~30 million Illumina reads into a reference transcriptome. We identified 62 and 104 transcripts, from X. index and L. elongatus, respectively, that were putatively acquired via horizontal gene transfer. By cross-referencing horizontal gene transfer prediction with a phylum-wide analysis of Pfam domains, we identified Clade 2-specific events. Of these, a GH12 cellulase from X. index was analysed phylogenetically and biochemically, revealing a likely bacterial origin and canonical enzymatic function. Horizontal gene transfer was previously shown to be a phenomenon that has contributed to the evolution of plant parasitism among nematodes. Our findings underline the importance and the extensiveness of this phenomenon in the evolution of plant-parasitic life styles in this speciose and widespread animal phylum.

  2. The Transcriptomes of Xiphinema index and Longidorus elongatus Suggest Independent Acquisition of Some Plant Parasitism Genes by Horizontal Gene Transfer in Early-Branching Nematodes

    Science.gov (United States)

    Danchin, Etienne G.J.; Perfus-Barbeoch, Laetitia; Rancurel, Corinne; Thorpe, Peter; Da Rocha, Martine; Bajew, Simon; Neilson, Roy; Sokolova (Guzeeva), Elena; Da Silva, Corinne; Guy, Julie; Labadie, Karine; Esmenjaud, Daniel; Helder, Johannes; Jones, John T.

    2017-01-01

    Nematodes have evolved the ability to parasitize plants on at least four independent occasions, with plant parasites present in Clades 1, 2, 10 and 12 of the phylum. In the case of Clades 10 and 12, horizontal gene transfer of plant cell wall degrading enzymes from bacteria and fungi has been implicated in the evolution of plant parasitism. We have used ribonucleic acid sequencing (RNAseq) to generate reference transcriptomes for two economically important nematode species, Xiphinema index and Longidorus elongatus, representative of two genera within the early-branching Clade 2 of the phylum Nematoda. We used a transcriptome-wide analysis to identify putative horizontal gene transfer events. This represents the first in-depth transcriptome analysis from any plant-parasitic nematode of this clade. For each species, we assembled ~30 million Illumina reads into a reference transcriptome. We identified 62 and 104 transcripts, from X. index and L. elongatus, respectively, that were putatively acquired via horizontal gene transfer. By cross-referencing horizontal gene transfer prediction with a phylum-wide analysis of Pfam domains, we identified Clade 2-specific events. Of these, a GH12 cellulase from X. index was analysed phylogenetically and biochemically, revealing a likely bacterial origin and canonical enzymatic function. Horizontal gene transfer was previously shown to be a phenomenon that has contributed to the evolution of plant parasitism among nematodes. Our findings underline the importance and the extensiveness of this phenomenon in the evolution of plant-parasitic life styles in this speciose and widespread animal phylum. PMID:29065523

  3. Protective Efficacy of Recombinant Turkey Herpes Virus (rHVT-H5) and Inactivated H5N1 Vaccines in Commercial Mulard Ducks against the Highly Pathogenic Avian Influenza (HPAI) H5N1 Clade 2.2.1 Virus.

    Science.gov (United States)

    Kilany, Walid H; Safwat, Marwa; Mohammed, Samy M; Salim, Abdullah; Fasina, Folorunso Oludayo; Fasanmi, Olubunmi G; Shalaby, Azhar G; Dauphin, Gwenaelle; Hassan, Mohammed K; Lubroth, Juan; Jobre, Yilma M

    2016-01-01

    In Egypt, ducks kept for commercial purposes constitute the second highest poultry population, at 150 million ducks/year. Hence, ducks play an important role in the introduction and transmission of avian influenza (AI) in the Egyptian poultry population. Attempts to control outbreaks include the use of vaccines, which have varying levels of efficacy and failure. To date, the effects of vaccine efficacy has rarely been determined in ducks. In this study, we evaluated the protective efficacy of a live recombinant vector vaccine based on a turkey Herpes Virus (HVT) expressing the H5 gene from a clade 2.2 H5N1 HPAIV strain (A/Swan/Hungary/499/2006) (rHVT-H5) and a bivalent inactivated H5N1 vaccine prepared from clade 2.2.1 and 2.2.1.1 H5N1 seeds in Mulard ducks. A 0.3ml/dose subcutaneous injection of rHVT-H5 vaccine was administered to one-day-old ducklings (D1) and another 0.5ml/dose subcutaneous injection of the inactivated MEFLUVAC was administered at 7 days (D7). Four separate challenge experiments were conducted at Days 21, 28, 35 and 42, in which all the vaccinated ducks were challenged with 106EID50/duck of H5N1 HPAI virus (A/chicken/Egypt/128s/2012(H5N1) (clade 2.2.1) via intranasal inoculation. Maternal-derived antibody regression and post-vaccination antibody immune responses were monitored weekly. Ducks vaccinated at 21, 28, 35 and 42 days with the rHVT-H5 and MEFLUVAC vaccines were protected against mortality (80%, 80%, 90% and 90%) and (50%, 70%, 80% and 90%) respectively, against challenges with the H5N1 HPAI virus. The amount of viral shedding and shedding rates were lower in the rHVT-H5 vaccine groups than in the MEFLUVAC groups only in the first two challenge experiments. However, the non-vaccinated groups shed significantly more of the virus than the vaccinated groups. Both rHVT-H5 and MEFLUVAC provide early protection, and rHVT-H5 vaccine in particular provides protection against HPAI challenge.

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

    KAUST Repository

    Parkinson, John Everett

    2016-02-11

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

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

    KAUST Repository

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

    2016-01-01

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

  6. Analysis of the WUSCHEL-RELATED HOMEOBOX gene family in Pinus pinaster: New insights into the gene family evolution.

    Science.gov (United States)

    Alvarez, José M; Bueno, Natalia; Cañas, Rafael A; Avila, Concepción; Cánovas, Francisco M; Ordás, Ricardo J

    2018-02-01

    WUSCHEL-RELATED HOMEOBOX (WOX) genes are key players controlling stem cells in plants and can be divided into three clades according to the time of their appearance during plant evolution. Our knowledge of stem cell function in vascular plants other than angiosperms is limited, they separated from gymnosperms ca 300 million years ago and their patterning during embryogenesis differs significantly. For this reason, we have used the model gymnosperm Pinus pinaster to identify WOX genes and perform a thorough analysis of their gene expression patterns. Using transcriptomic data from a comprehensive range of tissues and stages of development we have shown three major outcomes: that the P. pinaster genome encodes at least fourteen members of the WOX family spanning all the major clades, that the genome of gymnosperms contains a WOX gene with no homologues in angiosperms representing a transitional stage between intermediate- and WUS-clade proteins, and that we can detect discrete WUS and WOX5 transcripts for the first time in a gymnosperm. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. New insights into the organization and regulation of trichothecene biosynthetic genes in Trichoderma

    Science.gov (United States)

    Collectively, species of the genus Trichoderma can produce numerous structurally diverse secondary metabolites (SM). This ability is conferred by the presence of SM biosynthetic gene clusters in their genomes. Species of Trichoderma in the Brevicompactum clade are able to produce trichothecenes, a f...

  8. Atomic force microscopy imaging reveals the formation of ASIC/ENaC cross-clade ion channels.

    Science.gov (United States)

    Jeggle, Pia; Smith, Ewan St J; Stewart, Andrew P; Haerteis, Silke; Korbmacher, Christoph; Edwardson, J Michael

    2015-08-14

    ASIC and ENaC are co-expressed in various cell types, and there is evidence for a close association between them. Here, we used atomic force microscopy (AFM) to determine whether ASIC1a and ENaC subunits are able to form cross-clade hybrid ion channels. ASIC1a and ENaC could be co-isolated from detergent extracts of tsA 201 cells co-expressing the two subunits. Isolated proteins were incubated with antibodies against ENaC and Fab fragments against ASIC1a. AFM imaging revealed proteins that were decorated by both an antibody and a Fab fragment with an angle of ∼120° between them, indicating the formation of ASIC1a/ENaC heterotrimers. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Variations on a theme: diversification of cuticular hydrocarbons in a clade of cactophilic Drosophila

    Directory of Open Access Journals (Sweden)

    Jackson Larry L

    2011-06-01

    Full Text Available Abstract Background We characterized variation and chemical composition of epicuticular hydrocarbons (CHCs in the seven species of the Drosophila buzzatii cluster with gas chromatography/mass spectrometry. Despite the critical role of CHCs in providing resistance to desiccation and involvement in communication, such as courtship behavior, mating, and aggregation, few studies have investigated how CHC profiles evolve within and between species in a phylogenetic context. We analyzed quantitative differences in CHC profiles in populations of the D. buzzatii species cluster in order to assess the concordance of CHC differentiation with species divergence. Results Thirty-six CHC components were scored in single fly extracts with carbon chain lengths ranging from C29 to C39, including methyl-branched alkanes, n-alkenes, and alkadienes. Multivariate analysis of variance revealed that CHC amounts were significantly different among all species and canonical discriminant function (CDF analysis resolved all species into distinct, non-overlapping groups. Significant intraspecific variation was found in different populations of D. serido suggesting that this taxon is comprised of at least two species. We summarized CHC variation using CDF analysis and mapped the first five CHC canonical variates (CVs onto an independently derived period (per gene + chromosome inversion + mtDNA COI gene for each sex. We found that the COI sequences were not phylogenetically informative due to introgression between some species, so only per + inversion data were used. Positive phylogenetic signal was observed mainly for CV1 when parsimony methods and the test for serial independence (TFSI were used. These results changed when no outgroup species were included in the analysis and phylogenetic signal was then observed for female CV3 and/or CV4 and male CV4 and CV5. Finally, removal of divergent populations of D. serido significantly increased the amount of phylogenetic signal as

  10. Variations on a theme: diversification of cuticular hydrocarbons in a clade of cactophilic Drosophila

    Science.gov (United States)

    2011-01-01

    Background We characterized variation and chemical composition of epicuticular hydrocarbons (CHCs) in the seven species of the Drosophila buzzatii cluster with gas chromatography/mass spectrometry. Despite the critical role of CHCs in providing resistance to desiccation and involvement in communication, such as courtship behavior, mating, and aggregation, few studies have investigated how CHC profiles evolve within and between species in a phylogenetic context. We analyzed quantitative differences in CHC profiles in populations of the D. buzzatii species cluster in order to assess the concordance of CHC differentiation with species divergence. Results Thirty-six CHC components were scored in single fly extracts with carbon chain lengths ranging from C29 to C39, including methyl-branched alkanes, n-alkenes, and alkadienes. Multivariate analysis of variance revealed that CHC amounts were significantly different among all species and canonical discriminant function (CDF) analysis resolved all species into distinct, non-overlapping groups. Significant intraspecific variation was found in different populations of D. serido suggesting that this taxon is comprised of at least two species. We summarized CHC variation using CDF analysis and mapped the first five CHC canonical variates (CVs) onto an independently derived period (per) gene + chromosome inversion + mtDNA COI gene for each sex. We found that the COI sequences were not phylogenetically informative due to introgression between some species, so only per + inversion data were used. Positive phylogenetic signal was observed mainly for CV1 when parsimony methods and the test for serial independence (TFSI) were used. These results changed when no outgroup species were included in the analysis and phylogenetic signal was then observed for female CV3 and/or CV4 and male CV4 and CV5. Finally, removal of divergent populations of D. serido significantly increased the amount of phylogenetic signal as up to four out of five

  11. Flying lemurs – The 'flying tree shrews'? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade

    Directory of Open Access Journals (Sweden)

    Volobouev Vitaly

    2008-05-01

    Full Text Available Abstract Background Flying lemurs or Colugos (order Dermoptera represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires, the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous. Results To search for cytogenetic signatures that could help to clarify the evolutionary affinities within this superordinal group, we have established a genome-wide comparative map between human and the Malayan flying lemur (Galeopterus variegatus by reciprocal chromosome painting using both human and G. variegatus chromosome-specific probes. The 22 human autosomal paints and the X chromosome paint defined 44 homologous segments in the G. variegatus genome. A putative inversion on GVA 11 was revealed by the hybridization patterns of human chromosome probes 16 and 19. Fifteen associations of human chromosome segments (HSA were detected in the G. variegatus genome: HSA1/3, 1/10, 2/21, 3/21, 4/8, 4/18, 7/15, 7/16, 7/19, 10/16, 12/22 (twice, 14/15, 16/19 (twice. Reverse painting of G. variegatus chromosome-specific paints onto human chromosomes confirmed the above results, and defined the origin of the homologous human chromosomal segments in these associations. In total, G. variegatus paints revealed 49 homologous chromosomal segments in the HSA genome. Conclusion Comparative analysis of our map with published maps from representative species of other placental orders, including Scandentia, Primates, Lagomorpha and Rodentia, suggests a signature rearrangement (HSA2q/21 association that links Scandentia and Dermoptera to one sister clade. Our results thus provide new evidence for the hypothesis that Scandentia and Dermoptera have a closer phylogenetic relationship to each other than either of them has to Primates.

  12. Enrichment of Multilocus Sequence Typing Clade 1 with Oral Candida albicans Isolates in Patients with Untreated Periodontitis

    Science.gov (United States)

    McManus, Brenda A.; Maguire, Rory; Cashin, Phillipa J.; Claffey, Noel; Flint, Stephen; Abdulrahim, Mohammed H.

    2012-01-01

    This study investigated the prevalence and cell density of Candida species in periodontal pockets, healthy subgingival sites, and oral rinse samples of patients with untreated periodontitis. Twenty-one periodontitis patients underwent sampling at two periodontitis sites, and 19/21 of these patients underwent sampling at one periodontally healthy site. Both paper point and curette sampling techniques were employed. The periodontitis patients and 50 healthy subjects were also sampled by oral rinse. Candida isolates were recovered on CHROMagar Candida medium, and representative isolates were identified. Candida spp. were recovered from 10/21 (46.7%) periodontitis patients and from 16/50 (32%) healthy subjects. C. albicans predominated in both groups and was recovered from all Candida-positive subjects. Candida-positive periodontitis patients yielded Candida from periodontal pockets with average densities of 3,528 and 3,910 CFU/sample from curette and paper point samples, respectively, and 1,536 CFU/ml from oral rinse samples. The majority (18/19) of the healthy sites sampled from periodontitis patients were Candida negative. The 16 Candida-positive healthy subjects yielded an average of 279 CFU/ml from oral rinse samples. C. albicans isolates were investigated by multilocus sequence typing (MLST) to determine if specific clonal groups were associated with periodontitis. MLST analysis of 31 C. albicans isolates from periodontitis patients yielded 19 sequence types (STs), 13 of which were novel. Eleven STs belonged to MLST clade 1. In contrast, 16 C. albicans isolates from separate healthy subjects belonged to 16 STs, with 4 isolates belonging to clade 1. The distributions of STs between both groups were significantly different (P = 0.04) and indicated an enrichment of C. albicans isolates in periodontal pockets, which warrants a larger study. PMID:22875886

  13. A transposable element insertion in the susceptibility gene CsaMLO8 results in hypocotyl resistance to powdery mildew in cucumber

    NARCIS (Netherlands)

    Berg, J.A.; Appiano, M.; Santillán Martínez, M.I.; Hemans, F.W.K.; Vriezen, W.H.; Visser, R.G.F.; Bai, Y.; Schouten, H.J.

    2015-01-01

    Background - Powdery mildew (PM) is an important disease of cucumber (Cucumis sativus L.). CsaMLO8 was previously identified as a candidate susceptibility gene for PM in cucumber, for two reasons: 1) This gene clusters phylogenetically in clade V, which has previously been shown to harbour all known

  14. Dating the Time of Origin of Major Clades: Molecular Clocks and the Fossil Record

    Science.gov (United States)

    Smith, Andrew B.; Peterson, Kevin J.

    Molecular and paleontological data provide independent means of estimating when groups of organisms evolved in the geological past, but neither approach can be considered straightforward. The single most fundamental obstacle to developing an accurate estimate of times of origination from gene sequence data is variation in rates of molecular evolution, both through time and among lineages. Although various techniques have been proposed to circumvent this problem, none unambiguously allow the components of time and rate to be separated. Furthermore, problems of establishing accurate calibration points, correctly rooted phylogenies, and accurate estimates of branch length remain formidable. Conversely, paleontological dates fix only the latest possible time of divergence, and so probabilistic methods are required to set a lower boundary on origination dates. Realistic confidence intervals that take preservational biases into account are only just becoming available. Although molecular and paleontological approaches to dating often agree reasonably well, there are two notable areas of disagreement; when mammal and bird orders originated and when the major phyla originated. The discrepancy in dating bird/mammal ordinal origins probably reflects a global rock-record bias. Paleontological sampling in the Late Cretaceous is still too restricted geographically to draw any firm conclusions about the existence of a pre-Tertiary record for modern orders of bird or mammal from anywhere other than North America. Dating the time of origin of phyla is more complicated, and is confounded by both preservational biases and problems of molecular clock estimation.

  15. Horizontal acquisition of multiple mitochondrial genes from a parasitic plant followed by gene conversion with host mitochondrial genes

    Science.gov (United States)

    2010-01-01

    Background Horizontal gene transfer (HGT) is relatively common in plant mitochondrial genomes but the mechanisms, extent and consequences of transfer remain largely unknown. Previous results indicate that parasitic plants are often involved as either transfer donors or recipients, suggesting that direct contact between parasite and host facilitates genetic transfer among plants. Results In order to uncover the mechanistic details of plant-to-plant HGT, the extent and evolutionary fate of transfer was investigated between two groups: the parasitic genus Cuscuta and a small clade of Plantago species. A broad polymerase chain reaction (PCR) survey of mitochondrial genes revealed that at least three genes (atp1, atp6 and matR) were recently transferred from Cuscuta to Plantago. Quantitative PCR assays show that these three genes have a mitochondrial location in the one species line of Plantago examined. Patterns of sequence evolution suggest that these foreign genes degraded into pseudogenes shortly after transfer and reverse transcription (RT)-PCR analyses demonstrate that none are detectably transcribed. Three cases of gene conversion were detected between native and foreign copies of the atp1 gene. The identical phylogenetic distribution of the three foreign genes within Plantago and the retention of cytidines at ancestral positions of RNA editing indicate that these genes were probably acquired via a single, DNA-mediated transfer event. However, samplings of multiple individuals from two of the three species in the recipient Plantago clade revealed complex and perplexing phylogenetic discrepancies and patterns of sequence divergence for all three of the foreign genes. Conclusions This study reports the best evidence to date that multiple mitochondrial genes can be transferred via a single HGT event and that transfer occurred via a strictly DNA-level intermediate. The discovery of gene conversion between co-resident foreign and native mitochondrial copies suggests

  16. Horizontal acquisition of multiple mitochondrial genes from a parasitic plant followed by gene conversion with host mitochondrial genes

    Directory of Open Access Journals (Sweden)

    Hao Weilong

    2010-12-01

    Full Text Available Abstract Background Horizontal gene transfer (HGT is relatively common in plant mitochondrial genomes but the mechanisms, extent and consequences of transfer remain largely unknown. Previous results indicate that parasitic plants are often involved as either transfer donors or recipients, suggesting that direct contact between parasite and host facilitates genetic transfer among plants. Results In order to uncover the mechanistic details of plant-to-plant HGT, the extent and evolutionary fate of transfer was investigated between two groups: the parasitic genus Cuscuta and a small clade of Plantago species. A broad polymerase chain reaction (PCR survey of mitochondrial genes revealed that at least three genes (atp1, atp6 and matR were recently transferred from Cuscuta to Plantago. Quantitative PCR assays show that these three genes have a mitochondrial location in the one species line of Plantago examined. Patterns of sequence evolution suggest that these foreign genes degraded into pseudogenes shortly after transfer and reverse transcription (RT-PCR analyses demonstrate that none are detectably transcribed. Three cases of gene conversion were detected between native and foreign copies of the atp1 gene. The identical phylogenetic distribution of the three foreign genes within Plantago and the retention of cytidines at ancestral positions of RNA editing indicate that these genes were probably acquired via a single, DNA-mediated transfer event. However, samplings of multiple individuals from two of the three species in the recipient Plantago clade revealed complex and perplexing phylogenetic discrepancies and patterns of sequence divergence for all three of the foreign genes. Conclusions This study reports the best evidence to date that multiple mitochondrial genes can be transferred via a single HGT event and that transfer occurred via a strictly DNA-level intermediate. The discovery of gene conversion between co-resident foreign and native

  17. Evolution and Stress Responses of Gossypium hirsutum SWEET Genes.

    Science.gov (United States)

    Li, Wei; Ren, Zhongying; Wang, Zhenyu; Sun, Kuan; Pei, Xiaoyu; Liu, Yangai; He, Kunlun; Zhang, Fei; Song, Chengxiang; Zhou, Xiaojian; Zhang, Wensheng; Ma, Xiongfeng; Yang, Daigang

    2018-03-08

    The SWEET (sugars will eventually be exported transporters) proteins are sugar efflux transporters containing the MtN3_saliva domain, which affects plant development as well as responses to biotic and abiotic stresses. These proteins have not been functionally characterized in the tetraploid cotton, Gossypium hirsutum , which is a widely cultivated cotton species. In this study, we comprehensively analyzed the cotton SWEET gene family. A total of 55 putative G. hirsutum SWEET genes were identified. The GhSWEET genes were classified into four clades based on a phylogenetic analysis and on the examination of gene structural features. Moreover, chromosomal localization and an analysis of homologous genes in Gossypium arboreum , Gossypium raimondii , and G. hirsutum suggested that a whole-genome duplication, several tandem duplications, and a polyploidy event contributed to the expansion of the cotton SWEET gene family, especially in Clade III and IV. Analyses of cis -acting regulatory elements in the promoter regions, expression profiles, and artificial selection revealed that the GhSWEET genes were likely involved in cotton developmental processes and responses to diverse stresses. These findings may clarify the evolution of G. hirsutum SWEET gene family and may provide a foundation for future functional studies of SWEET proteins regarding cotton development and responses to abiotic stresses.

  18. Genomic evidence of bitter taste in snakes and phylogenetic analysis of bitter taste receptor genes in reptiles

    Directory of Open Access Journals (Sweden)

    Huaming Zhong

    2017-08-01

    Full Text Available As nontraditional model organisms with extreme physiological and morphological phenotypes, snakes are believed to possess an inferior taste system. However, the bitter taste sensation is essential to distinguish the nutritious and poisonous food resources and the genomic evidence of bitter taste in snakes is largely scarce. To explore the genetic basis of the bitter taste of snakes and characterize the evolution of bitter taste receptor genes (Tas2rs in reptiles, we identified Tas2r genes in 19 genomes (species corresponding to three orders of non-avian reptiles. Our results indicated contractions of Tas2r gene repertoires in snakes, however dramatic gene expansions have occurred in lizards. Phylogenetic analysis of the Tas2rs with NJ and BI methods revealed that Tas2r genes of snake species formed two clades, whereas in lizards the Tas2r genes clustered into two monophyletic clades and four large clades. Evolutionary changes (birth and death of intact Tas2r genes in reptiles were determined by reconciliation analysis. Additionally, the taste signaling pathway calcium homeostasis modulator 1 (Calhm1 gene of snakes was putatively functional, suggesting that snakes still possess bitter taste sensation. Furthermore, Phylogenetically Independent Contrasts (PIC analyses reviewed a significant correlation between the number of Tas2r genes and the amount of potential toxins in reptilian diets, suggesting that insectivores such as some lizards may require more Tas2rs genes than omnivorous and carnivorous reptiles.

  19. Genetics of reproductive isolation in the Drosophila simulans clade: complex epistasis underlying hybrid male sterility.

    Science.gov (United States)

    Cabot, E L; Davis, A W; Johnson, N A; Wu, C I

    1994-05-01

    We have analyzed the sterility associated with introgressions of the distal one-fourth of the X chromosome from either Drosophila mauritiana or Drosophila sechellia into the genome of Drosophila simulans using a series of visible and DNA markers. Because in Drosophila hybrids, male sterility is usually complete and is often tightly linked with each of several markers used in crosses, a simple genetic basis has generally been assumed. In our low resolution mapping experiment, we were not able to reject the null hypothesis that a single gene, introgressed from either D. mauritiana or D. sechellia, is the cause of male sterility. High resolution mapping, however, reveals a much more complex picture. At least three distinct factors from D. mauritiana, or two from D. sechellia, were identified that need to be jointly present to confer full sterility. Each individual factor by itself is relatively ineffective in causing sterility, or even a partial spermatogenic defect. Moreover, there appear to be more sterility factors on comparable introgressions from D. mauritiana than from D. sechellia. On the basis of these observations, we propose a model which suggests that multilocus weak allele interactions are a very common cause of reproductive incompatibility between closely related species. We also present theoretical argument and empirical evidence against extrapolating the results of within-species analysis to interpret the genetic basis of species differences. The implications of this model on the theories of evolution of species differences and the attempt to understand the mechanisms of hybrid sterility/inviability at the molecular level are discussed.

  20. nef gene sequence variation among HIV-1-infected African children

    Czech Academy of Sciences Publication Activity Database

    Chakraborty, R.; Reiniš, Milan; Rostron, T.; Philpott, S.; Dong, T.; D'Agostino, A.; Musoke, R.; de Silva, E.; Stumpf, M.; Weiser, B.; Burger, H.; Rowland-Jones, S.L.

    2006-01-01

    Roč. 7, č. 2 (2006), s. 75-84 ISSN 1464-2662 Grant - others:Fogarty International Center, NIH(US) 3D43TW00915; NIH(US) RO1 AI 42555 Institutional research plan: CEZ:AV0Z50520514 Keywords : HIV-1 nef gene * non-clade B * Kenya Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.674, year: 2006

  1. Grass cell wall feruloylation: distribution of bound ferulate and candidate gene expression in Brachypodium distachyon

    Directory of Open Access Journals (Sweden)

    Hugo Bruno Correa Molinari

    2013-03-01

    Full Text Available The cell walls of grasses such as wheat, maize, rice and sugar cane, contain large amounts of ferulate that is ester-linked to the cell wall polysaccharide glucuronoarabinoxylan (GAX. This ferulate is considered to limit the digestibility of polysaccharide in grass biomass as it forms covalent linkages between polysaccharide and lignin components. Candidate genes within a grass-specific clade of the BAHD acyl-coA transferase superfamily have been identified as being responsible for the ester linkage of ferulate to GAX. Manipulation of these BAHD genes may therefore be a biotechnological target for increasing efficiency of conversion of grass biomass into biofuel. Here, we describe the expression of these candidate genes and amounts of bound ferulate from various tissues and developmental stages of the model grass Brachypodium distachyon. BAHD candidate transcripts and significant amounts of bound ferulate were present in every tissue and developmental stage. We hypothesise that BAHD candidate genes similar to the recently described rice OsPMT gene (PMT sub-clade are principally responsible for the bound coumaric acid (pCA, and that other BAHD candidates (non-PMT sub-clade are responsible for bound ferulic acid (FA. There were some similarities with between the ratio of expression non-PMT / PMT genes and the ratio of bound FA / pCA between tissue types, compatible with this hypothesis. However, much further work to modify BAHD genes in grasses and to characterise the heterologously expressed proteins is required to demonstrate their function.

  2. Diversity of bacterial dimethylsulfoniopropionate degradation genes in surface seawater of Arctic Kongsfjorden.

    Science.gov (United States)

    Zeng, Yin-Xin; Qiao, Zong-Yun; Yu, Yong; Li, Hui-Rong; Luo, Wei

    2016-09-08

    Dimethylsulfoniopropionate (DMSP), which is the major source of organic sulfur in the world's oceans, plays a significant role in the global sulfur cycle. This compound is rapidly degraded by marine bacteria either by cleavage to dimethylsulfide (DMS) or demethylation to 3-methylmercaptopropionate (MMPA). The diversity of genes encoding bacterial demethylation (dmdA) and DMS production (dddL and dddP) were measured in Arctic Kongsfjorden. Both dmdA and dddL genes were detected in all stations along a transect from the outer to the inner fjord, while dddP gene was only found in the outer and middle parts of the fjord. The dmdA gene was completely confined to the Roseobacter clade, while the dddL gene was confined to the genus Sulfitobacter. Although the dddP gene pool was also dominated by homologs from the Roseobacter clade, there were a few dddP genes showing close relationships to both Alphaproteobacter and Gammaproteobacter. The results of this study suggest that the Roseobacter clade may play an important role in DMSP catabolism via both demethylation and cleavage pathways in surface waters of Kongsfjorden during summer.

  3. Ichthyophonus parasite phylogeny based on ITS rDNA structure prediction and alignment identifies six clades, with a single dominant marine type

    Science.gov (United States)

    Gregg, Jacob; Thompson, Rachel L.; Purcell, Maureen; Friedman, Carolyn S.; Hershberger, Paul

    2016-01-01

    Despite their widespread, global impact in both wild and cultured fishes, little is known of the diversity, transmission patterns, and phylogeography of parasites generally identified as Ichthyophonus. This study constructed a phylogeny based on the structural alignment of internal transcribed spacer (ITS) rDNA sequences to compare Ichthyophonus isolates from fish hosts in the Atlantic and Pacific oceans, and several rivers and aquaculture sites in North America, Europe, and Japan. Structure of the Ichthyophonus ITS1–5.8S–ITS2 transcript exhibited several homologies with other eukaryotes, and 6 distinct clades were identified within Ichthyophonus. A single clade contained a majority (71 of 98) of parasite isolations. This ubiquitous Ichthyophonus type occurred in 13 marine and anadromous hosts and was associated with epizootics in Atlantic herring, Chinook salmon, and American shad. A second clade contained all isolates from aquaculture, despite great geographic separation of the freshwater hosts. Each of the 4 remaining clades contained isolates from single host species. This study is the first to evaluate the genetic relationships among Ichthyophonus species across a significant portion of their host and geographic range. Additionally, parasite infection prevalence is reported in 16 fish species.

  4. Adaption of wild-bird origin H5Nx highly pathogenic avian influenza virus Clade 2.3.4.4 in vaccinated poultry

    Science.gov (United States)

    The 2014-2015 incursion of H5Nx clade 2.3.4.4 high pathogenicity avian influenza (HPAI) virus caused the largest animal health emergency in U.S. history and renewed interest in developing vaccines against these newly emergent viruses. Our previous research demonstrated several H5 vaccines with varyi...

  5. Reoccurrence of H5Nx clade 2.3.4.4 highly pathogenic avian influenza viruses in wild birds during 2016

    Science.gov (United States)

    The Asian-origin H5N1 A/goose/Guangdong/1/1996 (Gs/GD) lineage of high pathogenicity avian influenza viruses (HPAIV) has become widespread across four continents, affecting poultry, wild birds and humans. H5N1 HPAIV has evolved into multiple hemagglutinin (HA) genetic clades and reassorting with dif...

  6. Revision of the fossil batomorphs from the Cretaceous of Lebanon, and their impact on our understanding of the early step of the evolution of the clade

    DEFF Research Database (Denmark)

    Kachacha, Georges

    group to the remaining batomorphs. The remaining guitarfish from Lebanon present a crown paraphyletic assemblage sister to Rajidae, which, together, are included in the order Rajiformes. Eight Lebanese guitarfishes are distributed into four different clades which allowed me to reconsider the generic...

  7. Ichthyophonus parasite phylogeny based on ITS rDNA structure prediction and alignment identifies six clades, with a single dominant marine type.

    Science.gov (United States)

    Gregg, Jacob L; Powers, Rachel L; Purcell, Maureen K; Friedman, Carolyn S; Hershberger, Paul K

    2016-07-07

    Despite their widespread, global impact in both wild and cultured fishes, little is known of the diversity, transmission patterns, and phylogeography of parasites generally identified as Ichthyophonus. This study constructed a phylogeny based on the structural alignment of internal transcribed spacer (ITS) rDNA sequences to compare Ichthyophonus isolates from fish hosts in the Atlantic and Pacific oceans, and several rivers and aquaculture sites in North America, Europe, and Japan. Structure of the Ichthyophonus ITS1-5.8S-ITS2 transcript exhibited several homologies with other eukaryotes, and 6 distinct clades were identified within Ichthyophonus. A single clade contained a majority (71 of 98) of parasite isolations. This ubiquitous Ichthyophonus type occurred in 13 marine and anadromous hosts and was associated with epizootics in Atlantic herring, Chinook salmon, and American shad. A second clade contained all isolates from aquaculture, despite great geographic separation of the freshwater hosts. Each of the 4 remaining clades contained isolates from single host species. This study is the first to evaluate the genetic relationships among Ichthyophonus species across a significant portion of their host and geographic range. Additionally, parasite infection prevalence is reported in 16 fish species.

  8. Downregulation of RWA genes in hybrid aspen affects xylan acetylation and wood saccharification.

    Science.gov (United States)

    Pawar, Prashant Mohan-Anupama; Ratke, Christine; Balasubramanian, Vimal K; Chong, Sun-Li; Gandla, Madhavi Latha; Adriasola, Mathilda; Sparrman, Tobias; Hedenström, Mattias; Szwaj, Klaudia; Derba-Maceluch, Marta; Gaertner, Cyril; Mouille, Gregory; Ezcurra, Ines; Tenkanen, Maija; Jönsson, Leif J; Mellerowicz, Ewa J

    2017-06-01

    High acetylation of angiosperm wood hinders its conversion to sugars by glycoside hydrolases, subsequent ethanol fermentation and (hence) its use for biofuel production. We studied the REDUCED WALL ACETYLATION (RWA) gene family of the hardwood model Populus to evaluate its potential for improving saccharification. The family has two clades, AB and CD, containing two genes each. All four genes are expressed in developing wood but only RWA-A and -B are activated by master switches of the secondary cell wall PtNST1 and PtMYB21. Histochemical analysis of promoter::GUS lines in hybrid aspen (Populus tremula × tremuloides) showed activation of RWA-A and -B promoters in the secondary wall formation zone, while RWA-C and -D promoter activity was diffuse. Ectopic downregulation of either clade reduced wood xylan and xyloglucan acetylation. Suppressing both clades simultaneously using the wood-specific promoter reduced wood acetylation by 25% and decreased acetylation at position 2 of Xylp in the dimethyl sulfoxide-extracted xylan. This did not affect plant growth but decreased xylose and increased glucose contents in the noncellulosic monosaccharide fraction, and increased glucose and xylose yields of wood enzymatic hydrolysis without pretreatment. Both RWA clades regulate wood xylan acetylation in aspen and are promising targets to improve wood saccharification. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  9. Evolution of Phototrophy in the Chloroflexi Phylum Driven by Horizontal Gene Transfer

    Directory of Open Access Journals (Sweden)

    Lewis M. Ward

    2018-02-01

    Full Text Available The evolutionary mechanisms behind the extant distribution of photosynthesis is a point of substantial contention. Hypotheses range from the presence of phototrophy in the last universal common ancestor and massive gene loss in most lineages, to a later origin in Cyanobacteria followed by extensive horizontal gene transfer into the extant phototrophic clades, with intermediate scenarios that incorporate aspects of both end-members. Here, we report draft genomes of 11 Chloroflexi: the phototrophic Chloroflexia isolate Kouleothrix aurantiaca as well as 10 genome bins recovered from metagenomic sequencing of microbial mats found in Japanese hot springs. Two of these metagenome bins encode photrophic reaction centers and several of these bins form a metabolically diverse, monophyletic clade sister to the Anaerolineae class that we term Candidatus Thermofonsia. Comparisons of organismal (based on conserved ribosomal and phototrophy (reaction center and bacteriochlorophyll synthesis protein phylogenies throughout the Chloroflexi demonstrate that two new lineages acquired phototrophy independently via horizontal gene transfer (HGT from different ancestral donors within the classically phototrophic Chloroflexia class. These results illustrate a complex history of phototrophy within this group, with metabolic innovation tied to HGT. These observations do not support simple hypotheses for the evolution of photosynthesis that require massive character loss from many clades; rather, HGT appears to be the defining mechanic for the distribution of phototrophy in many of the extant clades in which it appears.

  10. How do Bacteria Adapt to the Red Sea? Cultivation and Genomic and Physiological Characterization of Oligotrophic Bacteria of the PS1, OM43, and SAR11 Clades

    KAUST Repository

    Jimenez Infante, Francy M.

    2015-05-01

    Given the high salinity, prevailing annual high temperatures, and ultra-oligotrophic conditions in the Red Sea isolation and characterization of important microbial groups thriving in this environment is important in understanding the ecological significance and metabolic capabilities of these communities. By using a high-­throughput cultivation technique in natural seawater amended with minute amounts of nutrients, members of the rare biosphere (PS1), methylotrophic Betaproteobacteria (OM43), and the ubiquitous and abundant SAR11 group (Pelagibacterales), were isolated in pure culture. Phylogenetic analyses of Red Sea isolates along with comparative genomics with close representatives from disparate provinces revealed ecotypes and genomic differentiation among the groups. Firstly, the PS1 alphaproteobacterial clade was found to be present in very low abundance in several metagenomic datasets form divergent environments. While strain RS24 (Red Sea) harbored genomic islands involved in polymer degradation, IMCC14465 (East (Japan) Sea) contained unique genes for degradation of aromatic compounds. Secondly, methylotrophic OM43 bacteria from the Red Sea (F5, G12 and H7) showed higher similarities with KB13 isolate from Hawaii, forming a ‘H-­RS’ (Hawaii-­Red Sea) cluster separate from HTCC2181 (Oregon isolate). HTCC2181 members were shown to prevail in cold, productive coastal environments and had an nqrA-­F system for energy generation by sodium motive force. On the contrary, H-­RS cluster members may be better adapted to warm and oligotrophic environments, and seem to generate energy by using a proton-­translocating NADH:Quinone oxidoreductase (complex I; nuoA-­N subunits). Moreover, F5, G12, and H7 had unique proteins related to resistance to UV, temperature and salinity, in addition to a heavy metal ‘resistance island’ as adaptive traits to cope with the environmental conditions in the Red Sea. Finally, description of the Red Sea Pelagibacterales

  11. Evolutionary history of Otophysi (Teleostei, a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation

    Directory of Open Access Journals (Sweden)

    Saitoh Kenji

    2011-06-01

    Full Text Available Abstract Background Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral lineage evolved into about two-thirds of this enormous biodiversity (≈ 7900 spp. and is currently distributed throughout the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history of this major freshwater fish clade, Otophysi, remains largely unexplored. To gain insight into the history of otophysan diversification, we constructed a timetree based on whole mitogenome sequences across 110 species representing 55 of the 64 families. Results Partitioned maximum likelihood analysis based on unambiguously aligned sequences (9923 bp confidently recovered the monophyly of Otophysi and the two constituent subgroups (Cypriniformes and Characiphysi. The latter clade comprised three orders (Gymnotiformes, Characiformes, Siluriformes, and Gymnotiformes was sister to the latter two groups. One of the two suborders in Characiformes (Characoidei was more closely related to Siluriformes than to its own suborder (Citharinoidei, rendering the characiforms paraphyletic. Although this novel relationship did not receive strong statistical support, it was supported by analyzing independent nuclear markers. A relaxed molecular clock Bayesian analysis of the divergence times and reconstruction of ancestral habitats on the timetree suggest a Pangaean origin and Mesozoic radiation of otophysans. Conclusions The present timetree demonstrates that survival of the ancestral lineages through the two consecutive mass extinctions on Pangaea, and subsequent radiations during the Jurassic through early Cretaceous shaped the modern familial diversity of otophysans. This evolutionary scenario is consistent with recent arguments based on biogeographic inferences and molecular divergence time estimates. No fossil otophysan, however, has been recorded before the Albian, the

  12. Evolutionary history of Otophysi (Teleostei), a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation.

    Science.gov (United States)

    Nakatani, Masanori; Miya, Masaki; Mabuchi, Kohji; Saitoh, Kenji; Nishida, Mutsumi

    2011-06-22

    Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral lineage evolved into about two-thirds of this enormous biodiversity (≈ 7900 spp.) and is currently distributed throughout the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history of this major freshwater fish clade, Otophysi, remains largely unexplored. To gain insight into the history of otophysan diversification, we constructed a timetree based on whole mitogenome sequences across 110 species representing 55 of the 64 families. Partitioned maximum likelihood analysis based on unambiguously aligned sequences (9923 bp) confidently recovered the monophyly of Otophysi and the two constituent subgroups (Cypriniformes and Characiphysi). The latter clade comprised three orders (Gymnotiformes, Characiformes, Siluriformes), and Gymnotiformes was sister to the latter two groups. One of the two suborders in Characiformes (Characoidei) was more closely related to Siluriformes than to its own suborder (Citharinoidei), rendering the characiforms paraphyletic. Although this novel relationship did not receive strong statistical support, it was supported by analyzing independent nuclear markers. A relaxed molecular clock Bayesian analysis of the divergence times and reconstruction of ancestral habitats on the timetree suggest a Pangaean origin and Mesozoic radiation of otophysans. The present timetree demonstrates that survival of the ancestral lineages through the two consecutive mass extinctions on Pangaea, and subsequent radiations during the Jurassic through early Cretaceous shaped the modern familial diversity of otophysans. This evolutionary scenario is consistent with recent arguments based on biogeographic inferences and molecular divergence time estimates. No fossil otophysan, however, has been recorded before the Albian, the early Cretaceous 100-112 Ma, creating an over 100

  13. Why do morphological phylogenies vary in quality? An investigation based on the comparative history of lizard clades.

    Science.gov (United States)

    Arnold, E N

    1990-05-22

    Phylogenies based on morphology vary considerably in their quality: some are robust and explicit with little conflict in the data set, whereas others are far more tenuous, with much conflict and many possible alternatives. The main primary reasons for untrue or inexplicit morphological phylogenies are: not enough characters developed between branching points, uncertain character polarity, poorly differentiated character states, homoplasy caused by parallelism or reversal, and extinction, which may remove species entirely from consideration and can make originally conflicting data sets misleadingly compatible, increasing congruence at the expense of truth. Extinction differs from other confounding factors in not being apparent either in the data set or in subsequent analysis. One possibility is that variation in the quality of morphological phylogenies has resulted from exposure to different ecological situations. To investigate this, it is necessary to compare the histories of the clades concerned. In the case of explicit morphological phylogenies, ecological and behavioural data can be integrated with them and it may then be possible to decide whether morphological characters are likely to have been elicited by the environments through which the clade has passed. The credibility of such results depends not only on the phylogeny being robust but also on its detailed topology: a pectinate phylogeny will often allow more certain and more explicit statements to be made about historical events. In the case of poor phylogenies, it is not possible to produce detailed histories, but they can be compared with robust phylogenies in the range of ecological situations occupied, and whether they occupy novel situations in comparison with their outgroups. LeQuesne testing can give information about niche homoplasy, and it may also be possible to see if morphological features are functionally associated with ecological parameters, even if the direction of change is unknown

  14. Multiple differences in calling songs and other traits between solitary and gregarious Mormon crickets from allopatric mtDNA clades

    Directory of Open Access Journals (Sweden)

    Bailey William V

    2007-01-01

    Full Text Available Abstract Background In acoustic species, traits such as male calling song are likely to diverge quickly between allopatric populations due to sexual selection, and divergence in parameters such as carrier frequency, chirp structure, and other important song characters can influence sexual isolation. Here we make use of two forms of Mormon crickets to examine differences in a broad suite of traits that have the potential to influence speciation via sexual isolation. Mormon crickets in "gregarious" populations aggregate into dense migratory bands, and females are the sexually competitive sex (sex-role reversal. There is also a non-outbreak "solitary" form. These two forms are largely but not perfectly correlated with a significant mtDNA subdivision within the species that is thought to have arisen in allopatry. Combined information about multiple, independently evolving traits, such as morphology and structural and behavioural differences in calling song, provides greater resolution of the overall differences between these allopatric populations, and allows us to assess their stage of divergence. We test two predictions, first that the forms differ in song and second that gregarious males are more reluctant to sing than solitary males due to sex role reversal. We also tested for a difference in the relationship between the size of the forewing resonator, the mirror, and carrier frequency, as most models of sound production in crickets indicate that mirror size should predict carrier frequency. Results Multivariate analyses showed that solitary and gregarious individuals from different populations representing the two mtDNA clades had almost non-overlapping distributions based on multiple song and morphological measurements. Carrier frequency differed between the two, and gregarious males were more reluctant to sing overall. Mirror size predicted carrier frequency; however, the relationship between mirror size and surface area varied between

  15. Broad antibody mediated cross-neutralization and preclinical immunogenicity of new codon-optimized HIV-1 clade CRF02_AG and G primary isolates.

    Directory of Open Access Journals (Sweden)

    Simon M Agwale

    Full Text Available Creation of an effective vaccine for HIV has been an elusive goal of the scientific community for almost 30 years. Neutralizing antibodies are assumed to be pivotal to the success of a prophylactic vaccine but previous attempts to make an immunogen capable of generating neutralizing antibodies to primary "street strain" isolates have resulted in responses of very limited breadth and potency. The objective of the study was to determine the breadth and strength of neutralizing antibodies against autologous and heterologous primary isolates in a cohort of HIV-1 infected Nigerians and to characterize envelopes from subjects with particularly broad or strong immune responses for possible use as vaccine candidates in regions predominated by HIV-1 CRF02_AG and G subtypes. Envelope vectors from a panel of primary Nigerian isolates were constructed and tested with plasma/sera from the same cohort using the PhenoSense HIV neutralizing antibody assay (Monogram Biosciences Inc, USA to assess the breadth and potency of neutralizing antibodies. The immediate goal of this study was realized by the recognition of three broadly cross-neutralizing sera: (NG2-clade CRF02_AG, NG3-clade CRF02_AG and NG9- clade G. Based on these findings, envelope gp140 sequences from NG2 and NG9, complemented with a gag sequence (Clade G and consensus tat (CRF02_AG and G antigens have been codon-optimized, synthesized, cloned and evaluated in BALB/c mice. The intramuscular administration of these plasmid DNA constructs, followed by two booster DNA immunizations, induced substantial specific humoral response against all constructs and strong cellular responses against the gag and tat constructs. These preclinical findings provide a framework for the design of candidate vaccine for use in regions where the HIV-1 epidemic is driven by clades CRF02_AG and G.

  16. Broad antibody mediated cross-neutralization and preclinical immunogenicity of new codon-optimized HIV-1 clade CRF02_AG and G primary isolates.

    Science.gov (United States)

    Agwale, Simon M; Forbi, Joseph C; Notka, Frank; Wrin, Terri; Wild, Jens; Wagner, Ralf; Wolf, Hans

    2011-01-01

    Creation of an effective vaccine for HIV has been an elusive goal of the scientific community for almost 30 years. Neutralizing antibodies are assumed to be pivotal to the success of a prophylactic vaccine but previous attempts to make an immunogen capable of generating neutralizing antibodies to primary "street strain" isolates have resulted in responses of very limited breadth and potency. The objective of the study was to determine the breadth and strength of neutralizing antibodies against autologous and heterologous primary isolates in a cohort of HIV-1 infected Nigerians and to characterize envelopes from subjects with particularly broad or strong immune responses for possible use as vaccine candidates in regions predominated by HIV-1 CRF02_AG and G subtypes. Envelope vectors from a panel of primary Nigerian isolates were constructed and tested with plasma/sera from the same cohort using the PhenoSense HIV neutralizing antibody assay (Monogram Biosciences Inc, USA) to assess the breadth and potency of neutralizing antibodies. The immediate goal of this study was realized by the recognition of three broadly cross-neutralizing sera: (NG2-clade CRF02_AG, NG3-clade CRF02_AG and NG9- clade G). Based on these findings, envelope gp140 sequences from NG2 and NG9, complemented with a gag sequence (Clade G) and consensus tat (CRF02_AG and G) antigens have been codon-optimized, synthesized, cloned and evaluated in BALB/c mice. The intramuscular administration of these plasmid DNA constructs, followed by two booster DNA immunizations, induced substantial specific humoral response against all constructs and strong cellular responses against the gag and tat constructs. These preclinical findings provide a framework for the design of candidate vaccine for use in regions where the HIV-1 epidemic is driven by clades CRF02_AG and G.

  17. Plastid phylogenomics and adaptive evolution of Gaultheria series Trichophyllae (Ericaceae), a clade from sky islands of the Himalaya-Hengduan Mountains.

    Science.gov (United States)

    Zhang, Ming-Ying; Fritsch, Peter W; Ma, Peng-Fei; Wang, Hong; Lu, Lu; Li, De-Zhu

    2017-05-01

    Gaultheria series Trichophyllae Airy Shaw is an angiosperm clade of high-alpine shrublets endemic to the Himalaya-Hengduan Mountains and characterized by recent species divergence and convergent character evolution that has until recently caused much confusion in species circumscription. Although multiple DNA sequence regions have been employed previously, phylogenetic relationships among species in the group have remained largely unresolved. Here we examined the effectiveness of the plastid genome for improving phylogenetic resolution within the G. series Trichophyllae clade. Plastid genomes of 31 samples representing all 19 recognized species of the series and three outgroup species were sequenced with Illumina Sequencing technology. Maximum likelihood (ML), maximum parsimony (MP) and Bayesian inference (BI) phylogenetic analyses were performed with various datasets, i.e., that from the whole plastid genome, coding regions, noncoding regions, large single-copy region (LSC) and inverted-repeat region a (IRa). The partitioned whole plastid genome with inverted-repeat region b (IRb) excluded was also analyzed with ML and BI. Tree topologies based on the whole plastid genome, noncoding regions, and LSC region datasets across all analyses, and that based on the partitioned dataset with ML and BI analyses, are identical and generally strongly supported. Gaultheria series Trichophyllae form a clade with three species and one variety that is sister to a clade of the remaining 16 species; the latter comprises seven main subclades. Interspecific relationships within the series are strongly supported except for those based on the coding-region and IRa-region datasets. Eight divergence hotspot regions, each possessing >5% percent variable sites, were screened across the whole plastid genome of the 28 individuals sampled in the series. Results of morphological character evolution reconstruction diagnose several clades, and a hypothesis of adaptive evolution for plant habit is

  18. Expression induction of P450 genes by imidacloprid in Nilaparvata lugens: A genome-scale analysis.

    Science.gov (United States)

    Zhang, Jianhua; Zhang, Yixi; Wang, Yunchao; Yang, Yuanxue; Cang, Xinzhu; Liu, Zewen

    2016-09-01

    The overexpression of P450 monooxygenase genes is a main mechanism for the resistance to imidacloprid, a representative neonicotinoid insecticide, in Nilaparvata lugens (brown planthopper, BPH). However, only two P450 genes (CYP6AY1 and CYP6ER1), among fifty-four P450 genes identified from BPH genome database, have been reported to play important roles in imidacloprid resistance until now. In this study, after the confirmation of important roles of P450s in imidacloprid resistance by the synergism analysis, the expression induction by imidacloprid was determined for all P450 genes. In the susceptible (Sus) strain, eight P450 genes in Clade4, eight in Clade3 and two in Clade2 were up-regulated by imidacloprid, among which three genes (CYP6CS1, CYP6CW1 and CYP6ER1, all in Clade3) were increased to above 4.0-fold and eight genes to above 2.0-fold. In contrast, no P450 genes were induced in Mito clade. Eight genes induced to above 2.0-fold were selected to determine their expression and induced levels in Huzhou population, in which piperonyl butoxide showed the biggest effects on imidacloprid toxicity among eight field populations. The expression levels of seven P450 genes were higher in Huzhou population than that in Sus strain, with the biggest differences for CYP6CS1 (9.8-fold), CYP6ER1 (7.7-fold) and CYP6AY1 (5.1-fold). The induction levels for all tested genes were bigger in Sus strain than that in Huzhou population except CYP425B1. Screening the induction of P450 genes by imidacloprid in the genome-scale will provide an overall view on the possible metabolic factors in the resistance to neonicotinoid insecticides. The further work, such as the functional study of recombinant proteins, will be performed to validate the roles of these P450s in imidacloprid resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Life history and biogeographic diversification of an endemic western North American freshwater fish clade using a comparative species tree approach.

    Science.gov (United States)

    Baumsteiger, Jason; Kinziger, Andrew P; Aguilar, Andres

    2012-12-01

    The west coast of North America contains a number of biogeographic freshwater provinces which reflect an ever-changing aquatic landscape. Clues to understanding this complex structure are often encapsulated genetically in the ichthyofauna, though frequently as unresolved evolutionary relationships and putative cryptic species. Advances in molecular phylogenetics through species tree analyses now allow for improved exploration of these relationships. Using a comprehensive approach, we analyzed two mitochondrial and nine nuclear loci for a group of endemic freshwater fish (sculpin-Cottus) known for a wide ranging distribution and complex species structure in this region. Species delimitation techniques identified three novel cryptic lineages, all well supported by phylogenetic analyses. Comparative phylogenetic analyses consistently found five distinct clades reflecting a number of unique biogeographic provinces. Some internal node relationships varied by species tree reconstruction method, and were associated with either Bayesian or maximum likelihood statistical approaches or between mitochondrial, nuclear, and combined datasets. Limited cases of mitochondrial capture were also evident, suggestive of putative ancestral hybridization between species. Biogeographic diversification was associated with four major regions and revealed historical faunal exchanges across regions. Mapping of an important life-history character (amphidromy) revealed two separate instances of trait evolution, a transition that has occurred repeatedly in Cottus. This study demonstrates the power of current phylogenetic methods, the need for a comprehensive phylogenetic approach, and the potential for sculpin to serve as an indicator of biogeographic history for native ichthyofauna in the region. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. The reporting of a Bacillus anthracis B-clade strain in South Africa after more than 20 years.

    Science.gov (United States)

    Lekota, K E; Hassim, A; Rogers, P; Dekker, E H; Last, R; de Klerk-Lorist, L; van Heerden, H

    2018-05-02

    Anthrax is a disease with an age old history in Africa caused by the Gram-positive endospore forming soil bacterium Bacillus anthracis. Epizootics of wild ungulates occur annually in the enzootic region of Pafuri, Kruger National Park (KNP) in the Limpopo Province of South Africa. Rigorous routine surveillance and diagnostics in KNP, has not revealed these rare isolates since the 1990s, despite unabated annual outbreaks. In 2011 a cheetah was diagnosed as anthrax positive from a private game reserve in Limpopo Province and reported to State Veterinary Services for further investigation. Isolation, molecular diagnostics, whole genome sequencing and comparative genomics were carried out for B. anthracis KC2011. Bacteriological and molecular diagnostics confirmed the isolate as B. anthracis. Subsequent typing and whole genome single nucleotide polymorphisms analysis indicated it clustered alongside B. anthracis SA A0091 in the B.Br.010 SNP branch. Unlike B. anthracis KrugerB strain, KC2011 strain has unique SNPs and represents a new branch in the B-clade. The isolation and genotypic characterisation of KC2011 demonstrates a gap in the reporting of anthrax outbreaks in the greater Limpopo province area. The identification of vulnerable and susceptible cheetah mortalities due to this strain has implications for conservation measures and disease control.

  1. Sympatric parallel diversification of major oak clades in the Americas and the origins of Mexican species diversity.

    Science.gov (United States)

    Hipp, Andrew L; Manos, Paul S; González-Rodríguez, Antonio; Hahn, Marlene; Kaproth, Matthew; McVay, John D; Avalos, Susana Valencia; Cavender-Bares, Jeannine

    2018-01-01

    Oaks (Quercus, Fagaceae) are the dominant tree genus of North America in species number and biomass, and Mexico is a global center of oak diversity. Understanding the origins of oak diversity is key to understanding biodiversity of northern temperate forests. A phylogenetic study of biogeography, niche evolution and diversification patterns in Quercus was performed using 300 samples, 146 species. Next-generation sequencing data were generated using the restriction-site associated DNA (RAD-seq) method. A time-calibrated maximum likelihood phylogeny was inferred and analyzed with bioclimatic, soils, and leaf habit data to reconstruct the biogeographic and evolutionary history of the American oaks. Our highly resolved phylogeny demonstrates sympatric parallel diversification in climatic niche, leaf habit, and diversification rates. The two major American oak clades arose in what is now the boreal zone and radiated, in parallel, from eastern North America into Mexico and Central America. Oaks adapted rapidly to niche transitions. The Mexican oaks are particularly numerous, not because Mexico is a center of origin, but because of high rates of lineage diversification associated with high rates of evolution along moisture gradients and between the evergreen and deciduous leaf habits. Sympatric parallel diversification in the oaks has shaped the diversity of North American forests. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  2. The Effect of Phylogeny, Environment and Morphology on Communities of a Lianescent Clade (Bignonieae-Bignoniaceae) in Neotropical Biomes

    Science.gov (United States)

    Alcantara, Suzana; Ree, Richard H.; Martins, Fernando R.; Lohmann, Lúcia G.

    2014-01-01

    The influence of ecological traits to the distribution and abundance of species is a prevalent issue in biodiversity science. Most studies of plant community assembly have focused on traits related to abiotic aspects or direct interactions among plants, with less attention paid to ignore indirect interactions, as those mediated by pollinators. Here, we assessed the influence of phylogeny, habitat, and floral morphology on ecological community structure in a clade of Neotropical lianas (tribe Bignonieae, Bignoniaceae). Our investigation was guided by the long-standing hypothesis that habitat specialization has promoted speciation in Bignonieae, while competition for shared pollinators influences species co-occurrence within communities. We analyzed a geo-referenced database for 94 local communities occurring across the Neotropics. The effect of floral morphological traits and abiotic variables on species co-occurrence was investigated, taking into account phylogenetic relationships. Habitat filtering seems to be the main process driving community assembly in Bignonieae, with environmental conditions limiting species distributions. Differing specialization to abiotic conditions might have evolved recently, in contrast to the general pattern of phylogenetic clustering found in communities of other diverse regions. We find no evidence that competition for pollinators affects species co-occurrence; instead, pollinator occurrence seems to have acted as an “environmental filter” in some habitats. PMID:24594706

  3. Gene Therapy

    Science.gov (United States)

    Gene therapy Overview Gene therapy involves altering the genes inside your body's cells in an effort to treat or stop disease. Genes contain your ... that don't work properly can cause disease. Gene therapy replaces a faulty gene or adds a new ...

  4. Species boundaries of Gulf of Mexico vestimentiferans (Polychaeta, Siboglinidae) inferred from mitochondrial genes

    Science.gov (United States)

    Pia Miglietta, Maria; Hourdez, Stephane; Cowart, Dominique A.; Schaeffer, Stephen W.; Fisher, Charles

    2010-11-01

    At least six morphospecies of vestimentiferan tubeworms are associated with cold seeps in the Gulf of Mexico (GOM). The physiology and ecology of the two best-studied species from depths above 1000 m in the upper Louisiana slope (Lamellibrachia luymesi and Seepiophila jonesi) are relatively well understood. The biology of one rare species from the upper slope (escarpiid sp. nov.) and three morphospecies found at greater depths in the GOM (Lamellibrachia sp. 1, L. sp. 2, and Escarpia laminata) are not as well understood. Here we address species distributions and boundaries of cold-seep tubeworms using phylogenetic hypotheses based on two mitochondrial genes. Fragments of the mitochondrial large ribosomal subunit rDNA (16S) and cytochrome oxidase subunit I (COI) genes were sequenced for 167 vestimentiferans collected from the GOM and analyzed in the context of other seep vestimentiferans for which sequence data were available. The analysis supported five monophyletic clades of vestimentiferans in the GOM. Intra-clade variation in both genes was very low, and there was no apparent correlation between the within-clade diversity and collection depth or location. Two of the morphospecies of Lamellibrachia from different depths in the GOM could not be distinguished by either mitochondrial gene. Similarly, E. laminata could not be distinguished from other described species of Escarpia from either the west coast of Africa or the eastern Pacific using COI. We suggest that the mitochondrial COI and 16S genes have little utility as barcoding markers for seep vestimentiferan tubeworms.

  5. Crimean-Congo hemorrhagic fever virus clades V and VI (Europe 1 and 2 in ticks in Kosovo, 2012.

    Directory of Open Access Journals (Sweden)

    Kurtesh Sherifi

    2014-09-01

    Full Text Available Despite being a small country, Kosovo represents one of the few foci of Crimean-Congo hemorrhagic fever (CCHF in Europe. The distribution of Kosovar tick vectors and the evolution of CCHF virus in ticks are both as yet unknown. A better description of the extent and the genetic diversity of CCHFV in ticks from endemic settings is essential, in order to be controlled. We investigated the 2012 distribution of Kosovar ticks alongside the prevalence and the phylogeography of tick-derived CCHFV. Hyalomma marginatum dominated in the endemic municipalities with 90.2% versus 24.3% in the non-endemic regions. Of 1,102 tested ticks, 40 (3.6% were CCHFV-positive, belonging to H. marginatum (29, Rhipicephalus bursa (10, and Ixodes ricinus (1. The virus strains clustered with clade V and VI related sequences. They fell into two lineages: Kosovo I and II. Kosovo I comprised strains recovered exclusively from R. bursa ticks and was closely related to AP92 prototype strain. Kosovo II clustered into Kosovo IIa, including human-derived strains, and IIb including only strains detected in H. marginatum and I. ricinus. Our phylogeographic reconstruction suggests two temporally distinct CCHFV introductions: the most probable location of the most recent common ancestor of Kosovo I lineage was in Greece (63 years ago and that of lineages IIa-b in Turkey (35 years ago. After each CCHFV introduction into Kosovo, subsequent lineage expansions suggest periods of in situ evolution. The study provides the first insight into the genetic variability and the origin of CCHFV in ticks from Kosovo. Our findings indicate the spreading of CCHFV to non-endemic areas, which underlines the importance of further studies in order to monitor and predict future CCHF outbreaks in Kosovo. The AP92-like strains appear to be more widespread than previously thought and may provide a promising target for experimental studies due to their assumed low pathogenicity.

  6. Safety and immunogenicity of adenovirus-vectored near-consensus HIV type 1 clade B gag vaccines in healthy adults.

    Science.gov (United States)

    Harro, Clayton D; Robertson, Michael N; Lally, Michelle A; O'Neill, Lori D; Edupuganti, Srilatha; Goepfert, Paul A; Mulligan, Mark J; Priddy, Frances H; Dubey, Sheri A; Kierstead, Lisa S; Sun, Xiao; Casimiro, Danilo R; DiNubile, Mark J; Shiver, John W; Leavitt, Randi Y; Mehrotra, Devan V

    2009-01-01

    Vaccines inducing pathogen-specific cell-mediated immunity are being developed using attenuated adenoviral (Ad) vectors. We report the results of two independent Phase I trials of similar replication-deficient Ad5 vaccines containing a near-consensus HIV-1 clade B gag transgene. Healthy HIV-uninfected adults were enrolled in two separate, multicenter, dose-escalating, blinded, placebo-controlled studies to assess the safety and immunogenicity of a three-dose homologous regimen of Ad5 and MRKAd5 HIV-1 gag vaccines given on day 1, week 4, and week 26. Adverse events were collected for 29 days following each intradeltoid injection. The primary immunogenicity endpoint was the proportion of subjects with a positive unfractionated Gag-specific IFN-gamma ELISPOT response measured 4 weeks after the last dose (week 30). Analyses were performed after combining data for each dose group from both protocols, stratifying by baseline Ad5 titers. Overall, 252 subjects were randomized to receive either vaccine or placebo, including 229 subjects (91%) who completed the study through week 30. Tolerability and immunogenicity did not appear to differ between the Ad5 and MRKAd5 vaccines. The frequency of injection-site reactions was dose dependent. Systemic adverse events were also dose dependent and more frequent in subjects with baseline Ad5 titers or =200, especially after the first dose. The percent of ELISPOT responders and the ELISPOT geometric means overall were significantly higher for all four vaccine doses studied compared to placebo, and were generally higher in vaccine recipients with baseline Ad5 titers or = 200. Ad5 titers increased after vaccination in a dose-dependent fashion. Both Ad5-vectored HIV-1 vaccines were generally well tolerated and induced cell-mediated immune responses against HIV Gag-peptides in the majority of healthy adults with baseline Ad5 titers vaccine-induced immunity to the Ad5 vector may dampen the CMI response to HIV Gag.

  7. The 'temporal effect' in hominids: Reinvestigating the nature of support for a chimp-human clade in bone morphology.

    Science.gov (United States)

    Pearson, Alannah; Groves, Colin; Cardini, Andrea

    2015-11-01

    In 2004, an analysis by Lockwood and colleagues of hard-tissue morphology, using geometric morphometrics on the temporal bone, succeeded in recovering the correct phylogeny of living hominids without resorting to potentially problematic methods for transforming continuous shape variables into meristic characters. That work has increased hope that by using modern analytical methods and phylogenetically informative anatomical data we might one day be able to accurately infer the relationships of hominins, including the closest extinct relatives of modern humans. In the present study, using 3D virtually generated models of the hominid temporal bone and a larger suite of geometric morphometric and comparative techniques, we have re-examined the evidence for a Pan-Homo clade. Despite differences in samples, as well as the type of raw data, the effect of measurement error (and especially landmark digitization by a different operator), but also a broader perspective brought in by our diverse set of approaches, our reanalysis largely supports Lockwood and colleagues' original results. However, by focusing not only mainly on shape (as in the original 2004 analysis) but also on size and 'size-corrected' (non-allometric) shape, we demonstrate that the strong phylogenetic signal in the temporal bone is largely related to similarities in size. Thus, with this study, we are not suggesting the use of a single 'character', such as size, for phylogenetic inference, but we do challenge the common view that shape, with its highly complex and multivariate nature, is necessarily more phylogenetically informative than size and that actually size and size-related shape variation (i.e., allometry) confound phylogenetic inference based on morphology. This perspective may in fact be less generalizable than often believed. Thus, while we confirm the original findings by Lockwood et al., we provide a deep reinterpretation of their nature and potential implications for hominid phylogenetics

  8. Significance of the identification in the Horn of Africa of an exceptionally deep branching Mycobacterium tuberculosis clade.

    Directory of Open Access Journals (Sweden)

    Yann Blouin

    Full Text Available Molecular and phylogeographic studies have led to the definition within the Mycobacterium tuberculosis complex (MTBC of a number of geotypes and ecotypes showing a preferential geographic location or host preference. The MTBC is thought to have emerged in Africa, most likely the Horn of Africa, and to have spread worldwide with human migrations. Under this assumption, there is a possibility that unknown deep branching lineages are present in this region. We genotyped by spoligotyping and multiple locus variable number of tandem repeats (VNTR analysis (MLVA 435 MTBC isolates recovered from patients. Four hundred and eleven isolates were collected in the Republic of Djibouti over a 12 year period, with the other 24 isolates originating from neighbouring countries. All major M. tuberculosis lineages were identified, with only two M. africanum and one M. bovis isolates. Upon comparison with typing data of worldwide origin we observed that several isolates showed clustering characteristics compatible with new deep branching. Whole genome sequencing (WGS of seven isolates and comparison with available WGS data from 38 genomes distributed in the different lineages confirms the identification of ancestral nodes for several clades and most importantly of one new lineage, here referred to as lineage 7. Investigation of specific deletions confirms the novelty of this lineage, and analysis of its precise phylogenetic position indicates that the other three superlineages constituting the MTBC emerged independently but within a relatively short timeframe from the Horn of Africa. The availability of such strains compared to the predominant lineages and sharing very ancient ancestry will open new avenues for identifying some of the genetic factors responsible for the success of the modern lineages. Additional deep branching lineages may be readily and efficiently identified by large-scale MLVA screening of isolates from sub-Saharan African countries followed by

  9. Recurrent signature patterns in HIV-1 B clade envelope glycoproteins associated with either early or chronic infections.

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    S Gnanakaran

    2011-09-01

    Full Text Available Here we have identified HIV-1 B clade Envelope (Env amino acid signatures from early in infection that may be favored at transmission, as well as patterns of recurrent mutation in chronic infection that may reflect common pathways of immune evasion. To accomplish this, we compared thousands of sequences derived by single genome amplification from several hundred individuals that were sampled either early in infection or were chronically infected. Samples were divided at the outset into hypothesis-forming and validation sets, and we used phylogenetically corrected statistical strategies to identify signatures, systematically scanning all of Env. Signatures included single amino acids, glycosylation motifs, and multi-site patterns based on functional or structural groupings of amino acids. We identified signatures near the CCR5 co-receptor-binding region, near the CD4 binding site, and in the signal peptide and cytoplasmic domain, which may influence Env expression and processing. Two signatures patterns associated with transmission were particularly interesting. The first was the most statistically robust signature, located in position 12 in the signal peptide. The second was the loss of an N-linked glycosylation site at positions 413-415; the presence of this site has been recently found to be associated with escape from potent and broad neutralizing antibodies, consistent with enabling a common pathway for immune escape during chronic infection. Its recurrent loss in early infection suggests it may impact fitness at the time of transmission or during early viral expansion. The signature patterns we identified implicate Env expression levels in selection at viral transmission or in early expansion, and suggest that immune evasion patterns that recur in many individuals during chronic infection when antibodies are present can be selected against when the infection is being established prior to the adaptive immune response.

  10. HIV Controllers Exhibit Enhanced Frequencies of Major Histocompatibility Complex Class II Tetramer+ Gag-Specific CD4+ T Cells in Chronic Clade C HIV-1 Infection.

    Science.gov (United States)

    Laher, Faatima; Ranasinghe, Srinika; Porichis, Filippos; Mewalal, Nikoshia; Pretorius, Karyn; Ismail, Nasreen; Buus, Søren; Stryhn, Anette; Carrington, Mary; Walker, Bruce D; Ndung'u, Thumbi; Ndhlovu, Zaza M

    2017-04-01

    Immune control of viral infections is heavily dependent on helper CD4 + T cell function. However, the understanding of the contribution of HIV-specific CD4 + T cell responses to immune protection against HIV-1, particularly in clade C infection, remains incomplete. Recently, major histocompatibility complex (MHC) class II tetramers have emerged as a powerful tool for interrogating antigen-specific CD4 + T cells without relying on effector functions. Here, we defined the MHC class II alleles for immunodominant Gag CD4 + T cell epitopes in clade C virus infection, constructed MHC class II tetramers, and then used these to define the magnitude, function, and relation to the viral load of HIV-specific CD4 + T cell responses in a cohort of untreated HIV clade C-infected persons. We observed significantly higher frequencies of MHC class II tetramer-positive CD4 + T cells in HIV controllers than progressors ( P = 0.0001), and these expanded Gag-specific CD4 + T cells in HIV controllers showed higher levels of expression of the cytolytic proteins granzymes A and B. Importantly, targeting of the immunodominant Gag41 peptide in the context of HLA class II DRB1*1101 was associated with HIV control ( r = -0.5, P = 0.02). These data identify an association between HIV-specific CD4 + T cell targeting of immunodominant Gag epitopes and immune control, particularly the contribution of a single class II MHC-peptide complex to the immune response against HIV-1 infection. Furthermore, these results highlight the advantage of the use of class II tetramers in evaluating HIV-specific CD4 + T cell responses in natural infections. IMPORTANCE Increasing evidence suggests that virus-specific CD4 + T cells contribute to the immune-mediated control of clade B HIV-1 infection, yet there remains a relative paucity of data regarding the role of HIV-specific CD4 + T cells in shaping adaptive immune responses in individuals infected with clade C, which is responsible for the majority of HIV

  11. Differential clade-specific HLA-B*3501 association with HIV-1 disease outcome is linked to immunogenicity of a single Gag epitope

    DEFF Research Database (Denmark)

    Matthews, Philippa C; Koyanagi, Madoka; Kløverpris, Henrik N

    2012-01-01

    -clade sequences, which critically reduces recognition of the Gag NY10 epitope. These data suggest that in spite of any inherent HLA-linked T-cell receptor repertoire differences that may exist, maximizing the breadth of the Gag-specific CD8(+) T-cell response, by the addition of even a single epitope, may......The strongest genetic influence on immune control in HIV-1 infection is the HLA class I genotype. Rapid disease progression in B-clade infection has been linked to HLA-B*35 expression, in particular to the less common HLA-B*3502 and HLA-B*3503 subtypes but also to the most prevalent subtype, HLA...

  12. Deletion and Gene Expression Analyses Define the Paxilline Biosynthetic Gene Cluster in Penicillium paxilli

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    Emily J. Parker

    2013-08-01

    Full Text Available The indole-diterpene paxilline is an abundant secondary metabolite synthesized by Penicillium paxilli. In total, 21 genes have been identified at the PAX locus of which six have been previously confirmed to have a functional role in paxilline biosynthesis. A combination of bioinformatics, gene expression and targeted gene replacement analyses were used to define the boundaries of the PAX gene cluster. Targeted gene replacement identified seven genes, paxG, paxA, paxM, paxB, paxC, paxP and paxQ that were all required for paxilline production, with one additional gene, paxD, required for regular prenylation of the indole ring post paxilline synthesis. The two putative transcription factors, PP104 and PP105, were not co-regulated with the pax genes and based on targeted gene replacement, including the double knockout, did not have a role in paxilline production. The relationship of indole dimethylallyl transferases involved in prenylation of indole-diterpenes such as paxilline or lolitrem B, can be found as two disparate clades, not supported by prenylation type (e.g., regular or reverse. This paper provides insight into the P. paxilli indole-diterpene locus and reviews the recent advances identified in paxilline biosynthesis.

  13. Production of three symbiosis-related fatty acids by Symbiodinium types in clades A-F associated with marine invertebrate larvae

    Science.gov (United States)

    Mies, M.; Chaves-Filho, A. B.; Miyamoto, S.; Güth, A. Z.; Tenório, A. A.; Castro, C. B.; Pires, D. O.; Calderon, E. N.; Sumida, P. Y. G.

    2017-12-01

    Symbiodinium are dinoflagellates engaged in a mutualistic symbiosis with multiple coral reef taxa. They are divided in nine different clades (A-I), which typically associate with different hosts. However, very little information is available on metabolic differences in Symbiodinium types, especially when associated with metazoan larvae. We tested whether three ω3 fatty acids (stearidonic acid, SDA; docosapentaenoic acid, DPA; and docosahexaenoic acid, DHA) that are typically translocated from Symbiodinium to its host are produced by Symbiodinium types within clades A-F associated with Mussismilia hispida (scleractinian coral), Berghia stephanieae (nudibranch), and Tridacna crocea (giant clam) larvae. We acquired and spawned broodstock for each host, cultured their larvae, and offered Symbiodinium types belonging to clades A-F. Samples were taken during a 72-h window after the offer of Symbiodinium, and fatty acids were extracted and analyzed by gas chromatography. The concentrations of SDA and DPA for all host larvae-dinoflagellate associations were low and variable, without trends. However, M. hispida planula larvae associated with Symbiodinium A1 and C1 had a statistically significant higher amount of DHA. The veliger larvae of B. stephanieae digested the Symbiodinium, and the amount of DHA remained constant throughout the experiment. The veliger larvae of T. crocea associated with Symbiodinium A1 and C1 also presented a higher amount of DHA, although not statistically different from the other types. These results show that Symbiodinium A1 and C1, in the case of M. hispida and T. crocea (which usually harbor strains within clades A and C), may contribute a small amount of DHA to the larvae of these organisms and form a stronger mutualism than other strains.

  14. [BIOINFORMATIC SEARCH AND PHYLOGENETIC ANALYSIS OF THE CELLULOSE SYNTHASE GENES OF FLAX (LINUM USITATISSIMUM)].

    Science.gov (United States)

    Pydiura, N A; Bayer, G Ya; Galinousky, D V; Yemets, A I; Pirko, Ya V; Podvitski, T A; Anisimova, N V; Khotyleva, L V; Kilchevsky, A V; Blume, Ya B

    2015-01-01

    A bioinformatic search of sequences encoding cellulose synthase genes in the flax genome, and their comparison to dicots orthologs was carried out. The analysis revealed 32 cellulose synthase gene candidates, 16 of which are highly likely to encode cellulose synthases, and the remaining 16--cellulose synthase-like proteins (Csl). Phylogenetic analysis of gene products of cellulose synthase genes allowed distinguishing 6 groups of cellulose synthase genes of different classes: CesA1/10, CesA3, CesA4, CesA5/6/2/9, CesA7 and CesA8. Paralogous sequences within classes CesA1/10 and CesA5/6/2/9 which are associated with the primary cell wall formation are characterized by a greater similarity within these classes than orthologous sequences. Whereas the genes controlling the biosynthesis of secondary cell wall cellulose form distinct clades: CesA4, CesA7, and CesA8. The analysis of 16 identified flax cellulose synthase gene candidates shows the presence of at least 12 different cellulose synthase gene variants in flax genome which are represented in all six clades of cellulose synthase genes. Thus, at this point genes of all ten known cellulose synthase classes are identify in flax genome, but their correct classification requires additional research.

  15. The pathogenecity of H5N1 highly pathogenic Avian Influenza (HPAI virus clade 2.3.2. in Indonesian indigenous chicken by contact tranmission with infected duck

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    R. Damayanti

    2017-05-01

    Full Text Available An experimental transmission study was conducted using nine healthy Indonesian indigenous chickens placed together with two 30 days old ducks which were experimentally infected with H5N1 HPAI clade 2.3.2 virus in the Biosafety Laboratory Level 3 (BSL-3 facilities. The aim of the study was to find out the pathogenicity of H5N1 HPAI virus clade 2.3.2 in Indonesian indigenous chickens. The study showed that within twenty four hours rearing, the chickens were exhibited mild clinical signs and by 48 hours, all of the chickens died, whereas the ducks survived but with severe clinical signs. The H5N1 HPAI virus has been successfully isolated from chickens and ducks swabs, confirming that those animals were infected by the virus. Histologically, the infected chicken encountered with severe inflammation reaction namely non suppuratives encephalitis, tracheitis, myocarditis, interstitial pneumonia, hepatitis, proventriculitis, enteritis, pancreatitis, nephritis and bursitis. Necrotizing spleen and pancreas were also prominent. Viral antigen was detected by immunohistochemistry staining in various affected visceral organs. This suggests that Indonesian indigenous chickens were susceptible to H5N1 HPAI virus clade 2.3.2 and it can be transmitted easily to Indonesian indigenous chickens by contact transmission with infected ducks.

  16. Delimiting Coalescence Genes (C-Genes) in Phylogenomic Data Sets.

    Science.gov (United States)

    Springer, Mark S; Gatesy, John

    2018-02-26

    coalescence methods have emerged as a popular alternative for inferring species trees with large genomic datasets, because these methods explicitly account for incomplete lineage sorting. However, statistical consistency of summary coalescence methods is not guaranteed unless several model assumptions are true, including the critical assumption that recombination occurs freely among but not within coalescence genes (c-genes), which are the fundamental units of analysis for these methods. Each c-gene has a single branching history, and large sets of these independent gene histories should be the input for genome-scale coalescence estimates of phylogeny. By contrast, numerous studies have reported the results of coalescence analyses in which complete protein-coding sequences are treated as c-genes even though exons for these loci can span more than a megabase of DNA. Empirical estimates of recombination breakpoints suggest that c-genes may be much shorter, especially when large clades with many species are the focus of analysis. Although this idea has been challenged recently in the literature, the inverse relationship between c-gene size and increased taxon sampling in a dataset-the 'recombination ratchet'-is a fundamental property of c-genes. For taxonomic groups characterized by genes with long intron sequences, complete protein-coding sequences are likely not valid c-genes and are inappropriate units of analysis for summary coalescence methods unless they occur in recombination deserts that are devoid of incomplete lineage sorting (ILS). Finally, it has been argued that coalescence methods are robust when the no-recombination within loci assumption is violated, but recombination must matter at some scale because ILS, a by-product of recombination, is the raison d'etre for coalescence methods. That is, extensive recombination is required to yield the large number of independently segregating c-genes used to infer a species tree. If coalescent methods are powerful

  17. Conserved Organisation of 45S rDNA Sites and rDNA Gene Copy Number among Major Clades of Early Land Plants

    Czech Academy of Sciences Publication Activity Database

    Rosato, M.; Kovařík, Aleš; Garilleti, R.; Rosselló, J. A.

    2016-01-01

    Roč. 11, č. 9 (2016), č. článku e0162544. E-ISSN 1932-6203 R&D Projects: GA ČR GBP501/12/G090 Institutional support: RVO:68081707 Keywords : molecular cytogenetic analyses * nuclear ribosomal dna Subject RIV: BO - Biophysics Impact factor: 2.806, year: 2016

  18. Expansion and Functional Divergence of AP2 Group Genes in Spermatophytes Determined by Molecular Evolution and Arabidopsis Mutant Analysis

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    Pengkai Wang

    2016-09-01

    Full Text Available The APETALA2 (AP2 genes represent the AP2 group within a large group of DNA-binding proteins called AP2/EREBP. The AP2 gene is functional and necessary for flower development, stem cell maintenance, and seed development, whereas the other members of AP2 group redundantly affect flowering time. Here we study the phylogeny of AP2 group genes in spermatophytes. Spermatophyte AP2 group genes can be classified into AP2 and TOE types, six clades, and we found that the AP2 group homologs in gymnosperms belong to the AP2 type, whereas TOE types are absent, which indicates the AP2 type gene are more ancient and TOE type was split out of AP2 type and losing the major function. In Brassicaceae, the expansion of AP2 and TOE type lead to the gene number of AP2 group were up to six. Purifying selection appears to have been the primary driving force of spermatophyte AP2 group evolution, although positive selection occurred in the AP2 clade. The transition from exon to intron of AtAP2 in Arabidopsis mutant leads to the loss of gene function and the same situation was found in AtTOE2. Combining this evolutionary analysis and published research, the results suggest that typical AP2 group genes may first appear in gymnosperms and diverged in angiosperms, following expansion of group members and functional differentiation. In angiosperms, AP2 genes (AP2 clade inherited key functions from ancestors and other genes of AP2 group lost most function but just remained flowering time controlling in gene formation. In this study, the phylogenies of AP2 group genes in spermatophytes was analyzed, which supported the evidence for the research of gene functional evolution of AP2 group.

  19. Biogeography of the Pistia clade (Araceae): based on chloroplast and mitochondrial DNA sequences and Bayesian divergence time inference.

    Science.gov (United States)

    Renner, Susanne S; Zhang, Li-Bing

    2004-06-01

    Pistia stratiotes (water lettuce) and Lemna (duckweeds) are the only free-floating aquatic Araceae. The geographic origin and phylogenetic placement of these unrelated aroids present long-standing problems because of their highly modified reproductive structures and wide geographical distributions. We sampled chloroplast (trnL-trnF and rpl20-rps12 spacers, trnL intron) and mitochondrial sequences (nad1 b/c intron) for all genera implicated as close relatives of Pistia by morphological, restriction site, and sequencing data, and present a hypothesis about its geographic origin based on the consensus of trees obtained from the combined data, using Bayesian, maximum likelihood, parsimony, and distance analyses. Of the 14 genera closest to Pistia, only Alocasia, Arisaema, and Typhonium are species-rich, and the latter two were studied previously, facilitating the choice of representatives that span the roots of these genera. Results indicate that Pistia and the Seychelles endemic Protarum sechellarum are the basalmost branches in a grade comprising the tribes Colocasieae (Ariopsis, Steudnera, Remusatia, Alocasia, Colocasia), Arisaemateae (Arisaema, Pinellia), and Areae (Arum, Biarum, Dracunculus, Eminium, Helicodiceros, Theriophonum, Typhonium). Unexpectedly, all Areae genera are embedded in Typhonium, which throws new light on the geographic history of Areae. A Bayesian analysis of divergence times that explores the effects of multiple fossil and geological calibration points indicates that the Pistia lineage is 90 to 76 million years (my) old. The oldest fossils of the Pistia clade, though not Pistia itself, are 45-my-old leaves from Germany; the closest outgroup, Peltandreae (comprising a few species in Florida, the Mediterranean, and Madagascar), is known from 60-my-old leaves from Europe, Kazakhstan, North Dakota, and Tennessee. Based on the geographic ranges of close relatives, Pistia likely originated in the Tethys region, with Protarum then surviving on the

  20. Molecular evolution of the actin-like MreB protein gene family in wall-less bacteria.

    Science.gov (United States)

    Ku, Chuan; Lo, Wen-Sui; Kuo, Chih-Horng

    2014-04-18

    The mreB gene family encodes actin-like proteins that determine cell shape by directing cell wall synthesis and often exists in one to three copies in the genomes of non-spherical bacteria. Intriguingly, while most wall-less bacteria do not have this gene, five to seven mreB homologs are found in Spiroplasma and Haloplasma, which are both characterized by cell contractility. To investigate the molecular evolution of this gene family in wall-less bacteria, we sampled the available genome sequences from these two genera and other related lineages for comparative analysis. The gene phylogenies indicated that the mreB homologs in Haloplasma are more closely related to those in Firmicutes, whereas those in Spiroplasma form a separate clade. This finding suggests that the gene family expansions in these two lineages are the results of independent ancient duplications. Moreover, the Spiroplasma mreB homologs can be classified into five clades, of which the genomic positions are largely conserved. The inference of gene gains and losses suggests that there has been an overall trend to retain only one homolog from each of the five mreB clades in the evolutionary history of Spiroplasma. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Paralogous SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes differentially regulate leaf initiation and reproductive phase change in petunia.

    Science.gov (United States)

    Preston, Jill C; Jorgensen, Stacy A; Orozco, Rebecca; Hileman, Lena C

    2016-02-01

    Duplicated petunia clade-VI SPL genes differentially promote the timing of inflorescence and flower development, and leaf initiation rate. The timing of plant reproduction relative to favorable environmental conditions is a critical component of plant fitness, and is often associated with variation in plant architecture and habit. Recent studies have shown that overexpression of the microRNA miR156 in distantly related annual species results in plants with perennial characteristics, including late flowering, weak apical dominance, and abundant leaf production. These phenotypes are largely mediated through the negative regulation of a subset of genes belonging to the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) family of transcription factors. In order to determine how and to what extent paralogous SPL genes have partitioned their roles in plant growth and development, we functionally characterized petunia clade-VI SPL genes under different environmental conditions. Our results demonstrate that PhSBP1and PhSBP2 differentially promote discrete stages of the reproductive transition, and that PhSBP1, and possibly PhCNR, accelerates leaf initiation rate. In contrast to the closest homologs in annual Arabidopsis thaliana and Mimulus guttatus, PhSBP1 and PhSBP2 transcription is not mediated by the gibberellic acid pathway, but is positively correlated with photoperiod and developmental age. The developmental functions of clade-VI SPL genes have, thus, evolved following both gene duplication and speciation within the core eudicots, likely through differential regulation and incomplete sub-functionalization.

  2. Simultaneous gene finding in multiple genomes.

    Science.gov (United States)

    König, Stefanie; Romoth, Lars W; Gerischer, Lizzy; Stanke, Mario

    2016-11-15

    As the tree of life is populated with sequenced genomes ever more densely, the new challenge is the accurate and consistent annotation of entire clades of genomes. We address this problem with a new approach to comparative gene finding that takes a multiple genome alignment of closely related species and simultaneously predicts the location and structure of protein-coding genes in all input genomes, thereby exploiting negative selection and sequence conservation. The model prefers potential gene structures in the different genomes that are in agreement with each other, or-if not-where the exon gains and losses are plausible given the species tree. We formulate the multi-species gene finding problem as a binary labeling problem on a graph. The resulting optimization problem is NP hard, but can be efficiently approximated using a subgradient-based dual decomposition approach. The proposed method was tested on whole-genome alignments of 12 vertebrate and 12 Drosophila species. The accuracy was evaluated for human, mouse and Drosophila melanogaster and compared to competing methods. Results suggest that our method is well-suited for annotation of (a large number of) genomes of closely related species within a clade, in particular, when RNA-Seq data are available for many of the genomes. The transfer of existing annotations from one genome to another via the genome alignment is more accurate than previous approaches that are based on protein-spliced alignments, when the genomes are at close to medium distances. The method is implemented in C ++ as part of Augustus and available open source at http://bioinf.uni-greifswald.de/augustus/ CONTACT: stefaniekoenig@ymail.com or mario.stanke@uni-greifswald.deSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Progressive dysregulation of autonomic and HPA axis functions in HIV-1 clade C infection in South India.

    Science.gov (United States)

    Chittiprol, Seetharamaiah; Kumar, Adarsh M; Satishchandra, P; Taranath Shetty, K; Bhimasena Rao, R S; Subbakrishna, D K; Philip, Mariyamma; Satish, K S; Ravi Kumar, H; Kumar, Mahendra

    2008-01-01

    Human immunodeficiency virus type 1 (HIV-1) infection causes a wide spectrum of abnormalities in neurological, neuropsychological, and neuroendocrinological functions. Several studies report disturbance in autonomic nervous system (ANS) and hypothalamic pituitary-adrenal (HPA) axis function in HIV-1B infected individuals. However, no such investigations on the effect of HIV-1 clade C infection, particularly during the initial phase of the disease progression, have been reported. The present investigations were carried out longitudinally over a 2-year period at 12 monthly intervals in clinically asymptomatic HIV-1 clade C seropositive patients (n=120) and seronegative control subjects (n=29). We determined both the basal levels and the dynamic changes in plasma levels of norepinephrine (NE), epinephrine (E), adrenocorticotrophic hormone (ACTH) and cortisol (CORT). Studies were also extended longitudinally (at three separate yearly visits of each participant), to evaluate the response of autonomic and HPA axis to mirror star tracing challenge test (MSTCT) and the values were determined as area under the curve (AUC, corrected for baseline levels of NE, E, ACTH, and CORT). The findings show that the values of basal plasma NE levels, as well as NE response to MSTCT (AUC) at the first visit of HIV-1 seropositive individuals did not differ from those found in the control subjects (NE, pg/ml, HIV-1C=313.5+/-12.7 vs. controls=353.0+/-21.3; p=NS; AUC, HIV-1C=225+/-14.75 vs. controls=232.7+/-19.34; p=NS, respectively). At the subsequent two visits of HIV-1 positive patients however, NE response to MSTCT challenge was progressively attenuated (AUC=235+/-19.5 and 162.7+/-13.6; p<0.01 and 0.05, respectively) compared to that found at the first visit. On the other hand, plasma levels of E as well as E response to MSTCT at the first visit were significantly lower in HIV-1C seropositive individuals compared to those in the control subjects (pg/ml, HIV-1C=77.30+/-5.7 vs. controls

  4. Characterization of epidemic IncI1-Iγ plasmids harboring ambler class A and C genes in Escherichia coli and Salmonella enterica from animals and humans.

    Science.gov (United States)

    Smith, Hilde; Bossers, Alex; Harders, Frank; Wu, Guanghui; Woodford, Neil; Schwarz, Stefan; Guerra, Beatriz; Rodríguez, Irene; van Essen-Zandbergen, Alieda; Brouwer, Michael; Mevius, Dik

    2015-09-01

    The aim of the study was to identify the plasmid-encoded factors contributing to the emergence and spread of epidemic IncI1-Iγ plasmids obtained from Escherichia coli and Salmonella enterica isolates from animal and human reservoirs. For this, 251 IncI1-Iγ plasmids carrying various extended-spectrum β-lactamase (ESBL) or AmpC β-lactamase genes were compared using plasmid multilocus sequence typing (pMLST). Thirty-two of these plasmids belonging to different pMLST types were sequenced using Roche 454 and Illumina platforms. Epidemic IncI1-Iγ plasmids could be assigned to various dominant clades, whereas rarely detected plasmids clustered together as a distinct clade. Similar phylogenetic trees were obtained using only the plasmid backbone sequences, showing that the differences observed between the plasmids belonging to distinct clades resulted mainly from differences between their backbone sequences. Plasmids belonging to the various clades differed particularly in the presence/absence of genes encoding partitioning and addiction systems, which contribute to stable inheritance during cell division and plasmid maintenance. Despite this, plasmids belonging to the various phylogenetic clades also showed marked resistance gene associations, indicating the circulation of successful plasmid-gene combinations. The variation in traY and excA genes found in IncI1-Iγ plasmids is conserved within pMLST sequence types and plays a role in incompatibility, although functional study is needed to elucidate the role of these genes in plasmid epidemiology. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  5. Overexpression of the class D MADS-box gene Sl-AGL11 impacts fleshy tissue differentiation and structure in tomato fruits

    Science.gov (United States)

    MADS-box transcription factors are key elements of the genetic networks controlling flower and fruit development. Among these, the class D clade are involved in seed, ovule, and funiculus development. The tomato genome comprises two class D genes, Sl-AGL11 and Sl-MBP3, both displaying high expressio...

  6. Evolution and diversification of the CYC/TB1 gene family in Asteraceae--a comparative study in Gerbera (Mutisieae) and sunflower (Heliantheae).

    Science.gov (United States)

    Tähtiharju, Sari; Rijpkema, Anneke S; Vetterli, Adrien; Albert, Victor A; Teeri, Teemu H; Elomaa, Paula

    2012-04-01

    Plant-specific TCP domain transcription factors have been shown to regulate morphological novelties during plant evolution, including the complex architecture of the Asteraceae inflorescence that involves different types of flowers. We conducted comparative analysis of the CYCLOIDEA/TEOSINTE BRANCHED1 (CYC/TB1) gene family in Gerbera hybrida (gerbera) and Helianthus annuus (sunflower), two species that represent distant tribes within Asteraceae. Our data confirm that the CYC/TB1 gene family has expanded in Asteraceae, a condition that appears to be connected with the increased developmental complexity and evolutionary success of this large plant family. Phylogenetic analysis of the CYC/TB1 gene family revealed both shared and lineage-specific duplications in gerbera and sunflower, corresponding to the three gene lineages previously identified as specific to core eudicots: CYC1, CYC2, and CYC3. Expression analyses of early stages of flower primordia development indicated that especially within the CYC2 clade, with the greatest number of secondary gene duplications, gene expression patterns are conserved between the species and associated with flower and inflorescence development. All sunflower and gerbera CYC2 clade genes showed differential expression between developing flower types, being upregulated in marginal ray (and trans) flowers. One gene in gerbera (GhCYC3) and two in sunflower (HaCYC2d and HaCYC2c) were indicated to be strong candidates as regulators of ray flower identity, a function that is specific for Asteraceae. Our data further showed that other CYC2 clade genes are likely to have more specialized functions at the level of single flowers, including the late functions in floral reproductive organs that may be more conserved across plant families. The expression patterns of CYC1 and CYC3 clade genes showed more differences between the two species but still pointed to possible conserved functions during vegetative plant development. Pairwise protein

  7. Evolutionary maintenance of filovirus-like genes in bat genomes

    Directory of Open Access Journals (Sweden)

    Taylor Derek J

    2011-11-01

    Full Text Available Abstract Background Little is known of the biological significance and evolutionary maintenance of integrated non-retroviral RNA virus genes in eukaryotic host genomes. Here, we isolated novel filovirus-like genes from bat genomes and tested for evolutionary maintenance. We also estimated the age of filovirus VP35-like gene integrations and tested the phylogenetic hypotheses that there is a eutherian mammal clade and a marsupial/ebolavirus/Marburgvirus dichotomy for filoviruses. Results We detected homologous copies of VP35-like and NP-like gene integrations in both Old World and New World species of Myotis (bats. We also detected previously unknown VP35-like genes in rodents that are positionally homologous. Comprehensive phylogenetic estimates for filovirus NP-like and VP35-like loci support two main clades with a marsupial and a rodent grouping within the ebolavirus/Lloviu virus/Marburgvirus clade. The concordance of VP35-like, NP-like and mitochondrial gene trees with the expected species tree supports the notion that the copies we examined are orthologs that predate the global spread and radiation of the genus Myotis. Parametric simulations were consistent with selective maintenance for the open reading frame (ORF of VP35-like genes in Myotis. The ORF of the filovirus-like VP35 gene has been maintained in bat genomes for an estimated 13. 4 MY. ORFs were disrupted for the NP-like genes in Myotis. Likelihood ratio tests revealed that a model that accommodates positive selection is a significantly better fit to the data than a model that does not allow for positive selection for VP35-like sequences. Moreover, site-by-site analysis of selection using two methods indicated at least 25 sites in the VP35-like alignment are under positive selection in Myotis. Conclusions Our results indicate that filovirus-like elements have significance beyond genomic imprints of prior infection. That is, there appears to be, or have been, functionally maintained

  8. The nuclear genome of Rhazya stricta and the evolution of alkaloid diversity in a medically relevant clade of Apocynaceae.

    Science.gov (United States)

    Sabir, Jamal S M; Jansen, Robert K; Arasappan, Dhivya; Calderon, Virginie; Noutahi, Emmanuel; Zheng, Chunfang; Park, Seongjun; Sabir, Meshaal J; Baeshen, Mohammed N; Hajrah, Nahid H; Khiyami, Mohammad A; Baeshen, Nabih A; Obaid, Abdullah Y; Al-Malki, Abdulrahman L; Sankoff, David; El-Mabrouk, Nadia; Ruhlman, Tracey A

    2016-09-22

    Alkaloid accumulation in plants is activated in response to stress, is limited in distribution and specific alkaloid repertoires are variable across taxa. Rauvolfioideae (Apocynaceae, Gentianales) represents a major center of structural expansion in the monoterpenoid indole alkaloids (MIAs) yielding thousands of unique molecules including highly valuable chemotherapeutics. The paucity of genome-level data for Apocynaceae precludes a deeper understanding of MIA pathway evolution hindering the elucidation of remaining pathway enzymes and the improvement of MIA availability in planta or in vitro. We sequenced the nuclear genome of Rhazya stricta (Apocynaceae, Rauvolfioideae) and present this high quality assembly in comparison with that of coffee (Rubiaceae, Coffea canephora, Gentianales) and others to investigate the evolution of genome-scale features. The annotated Rhazya genome was used to develop the community resource, RhaCyc, a metabolic pathway database. Gene family trees were constructed to identify homologs of MIA pathway genes and to examine their evolutionary history. We found that, unlike Coffea, the Rhazya lineage has experienced many structural rearrangements. Gene tree analyses suggest recent, lineage-specific expansion and diversification among homologs encoding MIA pathway genes in Gentianales and provide candidate sequences with the potential to close gaps in characterized pathways and support prospecting for new MIA production avenues.

  9. The IQD gene family in soybean: structure, phylogeny, evolution and expression.

    Directory of Open Access Journals (Sweden)

    Lin Feng

    Full Text Available Members of the plant-specific IQ67-domain (IQD protein family are involved in plant development and the basal defense response. Although systematic characterization of this family has been carried out in Arabidopsis, tomato (Solanum lycopersicum, Brachypodium distachyon and rice (Oryza sativa, systematic analysis and expression profiling of this gene family in soybean (Glycine max have not previously been reported. In this study, we identified and structurally characterized IQD genes in the soybean genome. A complete set of 67 soybean IQD genes (GmIQD1-67 was identified using Blast search tools, and the genes were clustered into four subfamilies (IQD I-IV based on phylogeny. These soybean IQD genes are distributed unevenly across all 20 chromosomes, with 30 segmental duplication events, suggesting that segmental duplication has played a major role in the expansion of the soybean IQD gene family. Analysis of the Ka/Ks ratios showed that the duplicated genes of the GmIQD family primarily underwent purifying selection. Microsynteny was detected in most pairs: genes in clade 1-3 might be present in genome regions that were inverted, expanded or contracted after the divergence; most gene pairs in clade 4 showed high conservation with little rearrangement among these gene-residing regions. Of the soybean IQD genes examined, six were most highly expressed in young leaves, six in flowers, one in roots and two in nodules. Our qRT-PCR analysis of 24 soybean IQD III genes confirmed that these genes are regulated by MeJA stress. Our findings present a comprehensive overview of the soybean IQD gene family and provide insights into the evolution of this family. In addition, this work lays a solid foundation for further experiments aimed at determining the biological functions of soybean IQD genes in growth and development.

  10. Phylogenetics and evolution of Trx SET genes in fully sequenced land plants.

    Science.gov (United States)

    Zhu, Xinyu; Chen, Caoyi; Wang, Baohua

    2012-04-01

    Plant Trx SET proteins are involved in H3K4 methylation and play a key role in plant floral development. Genes encoding Trx SET proteins constitute a multigene family in which the copy number varies among plant species and functional divergence appears to have occurred repeatedly. To investigate the evolutionary history of the Trx SET gene family, we made a comprehensive evolutionary analysis on this gene family from 13 major representatives of green plants. A novel clustering (here named as cpTrx clade), which included the III-1, III-2, and III-4 orthologous groups, previously resolved was identified. Our analysis showed that plant Trx proteins possessed a variety of domain organizations and gene structures among paralogs. Additional domains such as PHD, PWWP, and FYR were early integrated into primordial SET-PostSET domain organization of cpTrx clade. We suggested that the PostSET domain was lost in some members of III-4 orthologous group during the evolution of land plants. At least four classes of gene structures had been formed at the early evolutionary stage of land plants. Three intronless orphan Trx SET genes from the Physcomitrella patens (moss) were identified, and supposedly, their parental genes have been eliminated from the genome. The structural differences among evolutionary groups of plant Trx SET genes with different functions were described, contributing to the design of further experimental studies.

  11. Cloning and analysis of two Ceratopteris thalictroides MADS-box genes

    Directory of Open Access Journals (Sweden)

    XU Daolan

    2014-06-01

    Full Text Available MADS-box transcription factors,as a large gene family,play an important role in plant growth and development,especially act as key regulators in controlling the identities of floral organs in flowering plants.They are also significant in the evolutionary revelation.In order to understand MADS-box genes,we need more information of MADS-box genes in non flowering plant.MADS-box genes of Ceratopteris thalictroides were selected to clone and analysis by using RACE method.Two MADS-box genes,designated CtMADS1 and CtMADS2 in C. thalictroides,were cloned.Analysis indicates that CtMADS1 is belonged to MIKC*-clade,while CtMADS2 is belonged to MIKCc-clade.Phylogeny suggests that these two MADS-box genes of C. thalictroides have a close relationship with flowering plants,the data indicates that at least two different MADS-box genes are homologous to floral homeotic genes existed in the last common ancestor of contemporary vascular plants.

  12. Prevalence and distribution of avian influenza a(H5N1) virus clade variants in live bird markets of Vietnam, 2011-2013.

    Science.gov (United States)

    Nguyen, Diep T; Bryant, Juliet E; Davis, C Todd; Nguyen, Long V; Pham, Long T; Loth, Leo; Inui, Ken; Nguyen, Tung; Jang, Yunho; To, Thanh L; Nguyen, Tho D; Hoang, Diep T; Do, Hoa T; Nguyen, Trang T; Newman, Scott; Jennifer Siembieda; Pham, Dong V

    2014-12-01

    Active surveillance for avian influenza (Al) viruses in poultry sold at live bird markets (LBMs) was conducted in 44 of 63 provinces throughout Vietnam over two periods from September 2011 to February 2012 and October 2012 to June 2013. The study objectives were to assess the prevalence of avian influenza type A, H5, and H5N1 subtype viruses and characterize the geographical and temporal distribution of H5N1 virus genetic variants across the country. Monthly sampling was conducted in 394 LBMs located in 372 communes. A total of 9790 oropharyngeal swabs from poultry were screened for influenza A virus by real-time reverse-transcriptase PCR Virus isolation was attempted on all positive samples in embryonated chicken eggs, and the HA1 region of each H5 virus isolate was sequenced. Market prevalence of H5 subtype virus was 32.2% (127/394) over the cumulative 15 mo of surveillance. Phylogenetic analyses indicated that clade 1.1 viruses persisted in the south, whereas three genetically distinct subgroups of dade 2.3.2.1 were found simultaneously in northern, central, and southern Vietnam. Clade 2.3.2.1c viruses first appeared in July 2012 and spread rapidly to the center and south of Vietnam in late 2012, where they were predominant among clade 2.3.2.1 viruses and were detected in both active LBM surveillance and poultry outbreaks. Given the overlapping geographic distribution of dade variants and the antigenic divergence previously described for these dades, current AI poultry vaccines used in Vietnam may require bivalent formulations containing representatives of both dade 1.1 and dade 2.3.2.1 viruses.

  13. High Ancient Genetic Diversity of Human Lice, Pediculus humanus, from Israel Reveals New Insights into the Origin of Clade B Lice.

    Science.gov (United States)

    Amanzougaghene, Nadia; Mumcuoglu, Kosta Y; Fenollar, Florence; Alfi, Shir; Yesilyurt, Gonca; Raoult, Didier; Mediannikov, Oleg

    2016-01-01

    The human head louse, Pediculus humanus capitis, is subdivided into several significantly divergent mitochondrial haplogroups, each with particular geographical distributions. Historically, they are among the oldest human parasites, representing an excellent marker for tracking older events in human evolutionary history. In this study, ancient DNA analysis using real-time polymerase chain reaction (qPCR), combined with conventional PCR, was applied to the remains of twenty-four ancient head lice and their eggs from the Roman period which were recovered from Israel. The lice and eggs were found in three combs, one of which was recovered from archaeological excavations in the Hatzeva area of the Judean desert, and two of which found in Moa, in the Arava region, close to the Dead Sea. Results show that the head lice remains dating approximately to 2,000 years old have a cytb haplogroup A, which is worldwide in distribution, and haplogroup B, which has thus far only been found in contemporary lice from America, Europe, Australia and, most recently, Africa. More specifically, this haplogroup B has a B36 haplotype, the most common among B haplogroups, and has been present in America for at least 4,000 years. The present findings confirm that clade B lice existed, at least in the Middle East, prior to contacts between Native Americans and Europeans. These results support a Middle Eastern origin for clade B followed by its introduction into the New World with the early peoples. Lastly, the presence of Acinetobacter baumannii DNA was demonstrated by qPCR and sequencing in four head lice remains belonging to clade A.

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

    Directory of Open Access Journals (Sweden)

    Teresa Nogueira

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

  15. Towards a molecular taxonomic key of the Aurantioideae subfamily using chloroplastic SNP diagnostic markers of the main clades genotyped by competitive allele-specific PCR.

    Science.gov (United States)

    Oueslati, Amel; Ollitrault, Frederique; Baraket, Ghada; Salhi-Hannachi, Amel; Navarro, Luis; Ollitrault, Patrick

    2016-08-18

    Chloroplast DNA is a primary source of molecular variations for phylogenetic analysis of photosynthetic eukaryotes. However, the sequencing and analysis of multiple chloroplastic regions is difficult to apply to large collections or large samples of natural populations. The objective of our work was to demonstrate that a molecular taxonomic key based on easy, scalable and low-cost genotyping method should be developed from a set of Single Nucleotide Polymorphisms (SNPs) diagnostic of well-established clades. It was applied to the Aurantioideae subfamily, the largest group of the Rutaceae family that includes the cultivated citrus species. The publicly available nucleotide sequences of eight plastid genomic regions were compared for 79 accessions of the Aurantioideae subfamily to search for SNPs revealing taxonomic differentiation at the inter-tribe, inter-subtribe, inter-genus and interspecific levels. Diagnostic SNPs (DSNPs) were found for 46 of the 54 clade levels analysed. Forty DSNPs were selected to develop KASPar markers and their taxonomic value was tested by genotyping 108 accessions of the Aurantioideae subfamily. Twenty-seven markers diagnostic of 24 clades were validated and they displayed a very high rate of transferability in the Aurantioideae subfamily (only 1.2 % of missing data on average). The UPGMA from the validated markers produced a cladistic organisation that was highly coherent with the previous phylogenetic analysis based on the sequence data of the eight plasmid regions. In particular, the monophyletic origin of the "true citrus" genera plus Oxanthera was validated. However, some clarification remains necessary regarding the organisation of the other wild species of the Citreae tribe. We validated the concept that with well-established clades, DSNPs can be selected and efficiently transformed into competitive allele-specific PCR markers (KASPar method) allowing cost-effective highly efficient cladistic analysis in large collections at

  16. Genetic and codon usage bias analyses of polymerase genes of equine influenza virus and its relation to evolution.

    Science.gov (United States)

    Bera, Bidhan Ch; Virmani, Nitin; Kumar, Naveen; Anand, Taruna; Pavulraj, S; Rash, Adam; Elton, Debra; Rash, Nicola; Bhatia, Sandeep; Sood, Richa; Singh, Raj Kumar; Tripathi, Bhupendra Nath

    2017-08-23

    Equine influenza is a major health problem of equines worldwide. The polymerase genes of influenza virus have key roles in virus replication, transcription, transmission between hosts and pathogenesis. Hence, the comprehensive genetic and codon usage bias of polymerase genes of equine influenza virus (EIV) were analyzed to elucidate the genetic and evolutionary relationships in a novel perspective. The group - specific consensus amino acid substitutions were identified in all polymerase genes of EIVs that led to divergence of EIVs into various clades. The consistent amino acid changes were also detected in the Florida clade 2 EIVs circulating in Europe and Asia since 2007. To study the codon usage patterns, a total of 281,324 codons of polymerase genes of EIV H3N8 isolates from 1963 to 2015 were systemically analyzed. The polymerase genes of EIVs exhibit a weak codon usage bias. The ENc-GC3s and Neutrality plots indicated that natural selection is the major influencing factor of codon usage bias, and that the impact of mutation pressure is comparatively minor. The methods for estimating host imposed translation pressure suggested that the polymerase acidic (PA) gene seems to be under less translational pressure compared to polymerase basic 1 (PB1) and polymerase basic 2 (PB2) genes. The multivariate statistical analysis of polymerase genes divided EIVs into four evolutionary diverged clusters - Pre-divergent, Eurasian, Florida sub-lineage 1 and 2. Various lineage specific amino acid substitutions observed in all polymerase genes of EIVs and especially, clade 2 EIVs underwent major variations which led to the emergence of a phylogenetically distinct group of EIVs originating from Richmond/1/07. The codon usage bias was low in all the polymerase genes of EIVs that was influenced by the multiple factors such as the nucleotide compositions, mutation pressure, aromaticity and hydropathicity. However, natural selection was the major influencing factor in defining the

  17. [Genetic structure of Hemibarbus labeo and Hemibarbus medius in South China based on mtDNA COI and ND5 genes].

    Science.gov (United States)

    Lan, Zhao Jun; Lin, Long Feng; Zhao, Jun

    2017-04-18

    Both Hemibarbus labeo and H. medius (Cypriniformes: Cyprinidae: Gobioninae) are primary freshwater fishes and are widely distributed. As such, they provide an ideal model for phylogeographical studies. However, the similarity in morphological characters between these two species made the description of their distributions and the validation of species quite challenging. Here we employed variations in the DNA sequences of mitochondrial COI and ND5 genes (2151 bp) to solve this challenge and to study the population genetics structure of these two species. Among the 130 specimens belonging to 8 populations of H. labeo and 9 populations of H. medius from 17 drainage systems in southern China,196 variable sites (9.1% in the full sequences) falling into 50 haplotypes were identified. The haplotype diversity (h) and the nucleotide diversity (π) were 0.964 and 0.019, respectively, indicating a high level of genetic diversity and an evolutionary potential in both species. The result of neighbor-joining tree based on composite nucleotide sequences of the mtDNA COI and ND5 genes showed that the H. labeo and H. medius fell into two major clades (clade1and clade2): clade1was composed of some specimens of Oujiang River, all the specimens of Hanjiang River and Jiulongjiang River, whereas all remaining populations fell in clade2. The genetic distance between clade I and clade II was 0.036, while that between H. labeo and H. medius was 0.027. The haplotype network analyses indicated that the populations of Hanjiang River and Jiulongjiang River had relatively high genetic variation with the rest rivers. The po-pulations of Hainan Island migrated northward to Moyangjaing River. Haplotypes of the rivers of Hainan Island and Moyangjang River had relatively higher genetic variation with the Yangtze River than Pearl River. The populations of Xiangjiang River had no genetic variation with the populations of Guijiang River and Liujiang River. Analysis of molecular variance (AMOVA

  18. A Novel Extracellular Gut Symbiont in the Marine Worm Priapulus caudatus (Priapulida) Reveals an Alphaproteobacterial Symbiont Clade of the Ecdysozoa

    OpenAIRE

    Kroer, Paul; Kjeldsen, Kasper U.; Nyengaard, Jens R.; Schramm, Andreas; Funch, Peter

    2016-01-01

    Priapulus caudatus (phylum Priapulida) is a benthic marine predatory worm with a cosmopolitan distribution. In its digestive tract we detected symbiotic bacteria that were consistently present in specimens collected over eight years from three sites at the Swedish west coast. Based on their 16S rRNA gene sequence, these symbionts comprise a novel genus of the order Rickettsiales (Alphaproteobacteria). Electron microscopy and fluorescence in situ hybridization (FISH) identified them as extrace...

  19. Comparative Genomics of Non-TNL Disease Resistance Genes from Six Plant Species.

    Science.gov (United States)

    Nepal, Madhav P; Andersen, Ethan J; Neupane, Surendra; Benson, Benjamin V

    2017-09-30

    Disease resistance genes (R genes), as part of the plant defense system, have coevolved with corresponding pathogen molecules. The main objectives of this project were to identify non-Toll interleukin receptor, nucleotide-binding site, leucine-rich repeat (nTNL) genes and elucidate their evolutionary divergence across six plant genomes. Using reference sequences from Arabidopsis , we investigated nTNL orthologs in the genomes of common bean, Medicago , soybean, poplar, and rice. We used Hidden Markov Models for sequence identification, performed model-based phylogenetic analyses, visualized chromosomal positioning, inferred gene clustering, and assessed gene expression profiles. We analyzed 908 nTNL R genes in the genomes of the six plant species, and classified them into 12 subgroups based on the presence of coiled-coil (CC), nucleotide binding site (NBS), leucine rich repeat (LRR), resistance to Powdery mildew 8 (RPW8), and BED type zinc finger domains. Traditionally classified CC-NBS-LRR (CNL) genes were nested into four clades (CNL A-D) often with abundant, well-supported homogeneous subclades of Type-II R genes. CNL-D members were absent in rice, indicating a unique R gene retention pattern in the rice genome. Genomes from Arabidopsis , common bean, poplar and soybean had one chromosome without any CNL R genes. Medicago and Arabidopsis had the highest and lowest number of gene clusters, respectively. Gene expression analyses suggested unique patterns of expression for each of the CNL clades. Differential gene expression patterns of the nTNL genes were often found to correlate with number of introns and GC content, suggesting structural and functional divergence.

  20. Origin and distribution of epipolythiodioxopiperazine (ETP gene clusters in filamentous ascomycetes

    Directory of Open Access Journals (Sweden)

    Gardiner Donald M

    2007-09-01

    Full Text Available Abstract Background Genes responsible for biosynthesis of fungal secondary metabolites are usually tightly clustered in the genome and co-regulated with metabolite production. Epipolythiodioxopiperazines (ETPs are a class of secondary metabolite toxins produced by disparate ascomycete fungi and implicated in several animal and plant diseases. Gene clusters responsible for their production have previously been defined in only two fungi. Fungal genome sequence data have been surveyed for the presence of putative ETP clusters and cluster data have been generated from several fungal taxa where genome sequences are not available. Phylogenetic analysis of cluster genes has been used to investigate the assembly and heredity of these gene clusters. Results Putative ETP gene clusters are present in 14 ascomycete taxa, but absent in numerous other ascomycetes examined. These clusters are discontinuously distributed in ascomycete lineages. Gene content is not absolutely fixed, however, common genes are identified and phylogenies of six of these are separately inferred. In each phylogeny almost all cluster genes form monophyletic clades with non-cluster fungal paralogues being the nearest outgroups. This relatedness of cluster genes suggests that a progenitor ETP gene cluster assembled within an ancestral taxon. Within each of the cluster clades, the cluster genes group together in consistent subclades, however, these relationships do not always reflect the phylogeny of ascomycetes. Micro-synteny of several of the genes within the clusters provides further support for these subclades. Conclusion ETP gene clusters appear to have a single origin and have been inherited relatively intact rather than assembling independently in the different ascomycete lineages. This progenitor cluster has given rise to a small number of distinct phylogenetic classes of clusters that are represented in a discontinuous pattern throughout ascomycetes. The disjunct heredity of

  1. Pathogenicity island mobility and gene content.

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Kelly Porter

    2013-10-01

    Key goals towards national biosecurity include methods for analyzing pathogens, predicting their emergence, and developing countermeasures. These goals are served by studying bacterial genes that promote pathogenicity and the pathogenicity islands that mobilize them. Cyberinfrastructure promoting an island database advances this field and enables deeper bioinformatic analysis that may identify novel pathogenicity genes. New automated methods and rich visualizations were developed for identifying pathogenicity islands, based on the principle that islands occur sporadically among closely related strains. The chromosomally-ordered pan-genome organizes all genes from a clade of strains; gaps in this visualization indicate islands, and decorations of the gene matrix facilitate exploration of island gene functions. A %E2%80%9Clearned phyloblocks%E2%80%9D method was developed for automated island identification, that trains on the phylogenetic patterns of islands identified by other methods. Learned phyloblocks better defined termini of previously identified islands in multidrug-resistant Klebsiella pneumoniae ATCC BAA-2146, and found its only antibiotic resistance island.

  2. Nearly Complete 28S rRNA Gene Sequences Confirm New Hypotheses of Sponge Evolution

    Science.gov (United States)

    Thacker, Robert W.; Hill, April L.; Hill, Malcolm S.; Redmond, Niamh E.; Collins, Allen G.; Morrow, Christine C.; Spicer, Lori; Carmack, Cheryl A.; Zappe, Megan E.; Pohlmann, Deborah; Hall, Chelsea; Diaz, Maria C.; Bangalore, Purushotham V.

    2013-01-01

    The highly collaborative research sponsored by the NSF-funded Assembling the Porifera Tree of Life (PorToL) project is providing insights into some of the most difficult questions in metazoan systematics. Our understanding of phylogenetic relationships within the phylum Porifera has changed considerably with increased taxon sampling and data from additional molecular markers. PorToL researchers have falsified earlier phylogenetic hypotheses, discovered novel phylogenetic alliances, found phylogenetic homes for enigmatic taxa, and provided a more precise understanding of the evolution of skeletal features, secondary metabolites, body organization, and symbioses. Some of these exciting new discoveries are shared in the papers that form this issue of Integrative and Comparative Biology. Our analyses of over 300 nearly complete 28S ribosomal subunit gene sequences provide specific case studies that illustrate how our dataset confirms new hypotheses of sponge evolution. We recovered monophyletic clades for all 4 classes of sponges, as well as the 4 major clades of Demospongiae (Keratosa, Myxospongiae, Haploscleromorpha, and Heteroscleromorpha), but our phylogeny differs in several aspects from traditional classifications. In most major clades of sponges, families within orders appear to be paraphyletic. Although additional sampling of genes and taxa are needed to establish whether this pattern results from a lack of phylogenetic resolution or from a paraphyletic classification system, many of our results are congruent with those obtained from 18S ribosomal subunit gene sequences and complete mitochondrial genomes. These data provide further support for a revision of the traditional classification of sponges. PMID:23748742

  3. Factors predicting discordant virological and immunological responses to antiretroviral therapy in HIV-1 clade C infected Zulu/Xhosa in South Africa.

    Directory of Open Access Journals (Sweden)

    Boris Julg

    Full Text Available Factors predicting suboptimal CD4 cell recovery have been studied in HIV clade-B infected US and European populations. It is, however, uncertain to what extent these results are applicable to HIV clade-C infected African populations. Multivariate analysis using logistic regression and longitudinal analyses using mixed models were employed to assess the impact of age, gender, baseline CD4 cell count, hemoglobin, body mass index (BMI, tuberculosis and other opportunistic co-infections, and frequencies of regimen change on CD4 cell recovery at 12 and 30 months and on overtime change in CD4 cells among 442 virologically suppressed South Africans. Despite adequate virological response 37% (95% CI:32%-42% and 83% (95% CI:79%-86% of patients on antiretroviral therapy failed to restore CD4 cell counts ≥ 200 cells/mm(3 after 12 and ≥ 500 cells/mm(3 after 30 months, respectively, in this South African cohort. Critical risk factors for inadequate recovery were older age (p = 0.001 and nadir CD4 cell count at ART initiation (p<0.0001, while concurrent TB co-infection, BMI, baseline hemoglobin, gender and antiretroviral regimen were not significant risk factors. These data suggest that greater efforts are needed to identify and treat HAART-eligible patients prior to severe CD4 cell decline or achievement of advanced age.

  4. Factors predicting discordant virological and immunological responses to antiretroviral therapy in HIV-1 clade C infected Zulu/Xhosa in South Africa.

    Science.gov (United States)

    Julg, Boris; Poole, Danielle; Ghebremichael, Musie; Castilla, Carmen; Altfeld, Marcus; Sunpath, Henry; Murphy, Richard A; Walker, Bruce D

    2012-01-01

    Factors predicting suboptimal CD4 cell recovery have been studied in HIV clade-B infected US and European populations. It is, however, uncertain to what extent these results are applicable to HIV clade-C infected African populations. Multivariate analysis using logistic regression and longitudinal analyses using mixed models were employed to assess the impact of age, gender, baseline CD4 cell count, hemoglobin, body mass index (BMI), tuberculosis and other opportunistic co-infections, and frequencies of regimen change on CD4 cell recovery at 12 and 30 months and on overtime change in CD4 cells among 442 virologically suppressed South Africans. Despite adequate virological response 37% (95% CI:32%-42%) and 83% (95% CI:79%-86%) of patients on antiretroviral therapy failed to restore CD4 cell counts ≥ 200 cells/mm(3) after 12 and ≥ 500 cells/mm(3) after 30 months, respectively, in this South African cohort. Critical risk factors for inadequate recovery were older age (p = 0.001) and nadir CD4 cell count at ART initiation (p<0.0001), while concurrent TB co-infection, BMI, baseline hemoglobin, gender and antiretroviral regimen were not significant risk factors. These data suggest that greater efforts are needed to identify and treat HAART-eligible patients prior to severe CD4 cell decline or achievement of advanced age.

  5. Gene duplication, loss and selection in the evolution of saxitoxin biosynthesis in alveolates.

    Science.gov (United States)

    Murray, Shauna A; Diwan, Rutuja; Orr, Russell J S; Kohli, Gurjeet S; John, Uwe

    2015-11-01

    A group of marine dinoflagellates (Alveolata, Eukaryota), consisting of ∼10 species of the genus Alexandrium, Gymnodinium catenatum and Pyrodinium bahamense, produce the toxin saxitoxin and its analogues (STX), which can accumulate in shellfish, leading to ecosystem and human health impacts. The genes, sxt, putatively involved in STX biosynthesis, have recently been identified, however, the evolution of these genes within dinoflagellates is not clear. There are two reasons for this: uncertainty over the phylogeny of dinoflagellates; and that the sxt genes of many species of Alexandrium and other dinoflagellate genera are not known. Here, we determined the phylogeny of STX-producing and other dinoflagellates based on a concatenated eight-gene alignment. We determined the presence, diversity and phylogeny of sxtA, domains A1 and A4 and sxtG in 52 strains of Alexandrium, and a further 43 species of dinoflagellates and thirteen other alveolates. We confirmed the presence and high sequence conservation of sxtA, domain A4, in 40 strains (35 Alexandrium, 1 Pyrodinium, 4 Gymnodinium) of 8 species of STX-producing dinoflagellates, and absence from non-producing species. We found three paralogs of sxtA, domain A1, and a widespread distribution of sxtA1 in non-STX producing dinoflagellates, indicating duplication events in the evolution of this gene. One paralog, clade 2, of sxtA1 may be particularly related to STX biosynthesis. Similarly, sxtG appears to be generally restricted to STX-producing species, while three amidinotransferase gene paralogs were found in dinoflagellates. We investigated the role of positive (diversifying) selection following duplication in sxtA1 and sxtG, and found negative selection in clades of sxtG and sxtA1, clade 2, suggesting they were functionally constrained. Significant episodic diversifying selection was found in some strains in clade 3 of sxtA1, a clade that may not be involved in STX biosynthesis, indicating pressure for diversification

  6. Analysis of gene evolution and metabolic pathways using the Candida Gene Order Browser

    LENUS (Irish Health Repository)

    Fitzpatrick, David A

    2010-05-10

    Abstract Background Candida species are the most common cause of opportunistic fungal infection worldwide. Recent sequencing efforts have provided a wealth of Candida genomic data. We have developed the Candida Gene Order Browser (CGOB), an online tool that aids comparative syntenic analyses of Candida species. CGOB incorporates all available Candida clade genome sequences including two Candida albicans isolates (SC5314 and WO-1) and 8 closely related species (Candida dubliniensis, Candida tropicalis, Candida parapsilosis, Lodderomyces elongisporus, Debaryomyces hansenii, Pichia stipitis, Candida guilliermondii and Candida lusitaniae). Saccharomyces cerevisiae is also included as a reference genome. Results CGOB assignments of homology were manually curated based on sequence similarity and synteny. In total CGOB includes 65617 genes arranged into 13625 homology columns. We have also generated improved Candida gene sets by merging\\/removing partial genes in each genome. Interrogation of CGOB revealed that the majority of tandemly duplicated genes are under strong purifying selection in all Candida species. We identified clusters of adjacent genes involved in the same metabolic pathways (such as catabolism of biotin, galactose and N-acetyl glucosamine) and we showed that some clusters are species or lineage-specific. We also identified one example of intron gain in C. albicans. Conclusions Our analysis provides an important resource that is now available for the Candida community. CGOB is available at http:\\/\\/cgob.ucd.ie.

  7. Cenozoic biogeography and evolution in direct-developing frogs of Central America (Leptodactylidae: Eleutherodactylus) as inferred from a phylogenetic analysis of nuclear and mitochondrial genes.

    Science.gov (United States)

    Crawford, Andrew J; Smith, Eric N

    2005-06-01

    We report the first phylogenetic analysis of DNA sequence data for the Central American component of the genus Eleutherodactylus (Anura: Leptodactylidae: Eleutherodactylinae), one of the most ubiquitous, diverse, and abundant components of the Neotropical amphibian fauna. We obtained DNA sequence data from 55 specimens representing 45 species. Sampling was focused on Central America, but also included Bolivia, Brazil, Jamaica, and the USA. We sequenced 1460 contiguous base pairs (bp) of the mitochondrial genome containing ND2 and five neighboring tRNA genes, plus 1300 bp of the c-myc nuclear gene. The resulting phylogenetic inferences were broadly concordant between data sets and among analytical methods. The subgenus Craugastor is monophyletic and its initial radiation was potentially rapid and adaptive. Within Craugastor, the earliest splits separate three northern Central American species groups, milesi, augusti, and alfredi, from a clade comprising the rest of Craugastor. Within the latter clade, the rhodopis group as formerly recognized comprises three deeply divergent clades that do not form a monophyletic group; we therefore restrict the content of the rhodopis group to one of two northern clades, and use new names for the other northern (mexicanus group) and one southern clade (bransfordii group). The new rhodopis and bransfordii groups together form the sister taxon to a clade comprising the biporcatus, fitzingeri, mexicanus, and rugulosus groups. We used a Bayesian MCMC approach together with geological and biogeographic assumptions to estimate divergence times from the combined DNA sequence data. Our results corroborated three independent dispersal events for the origins of Central American Eleutherodactylus: (1) an ancestor of Craugastor entered northern Central America from South American in the early Paleocene, (2) an ancestor of the subgenus Syrrhophus entered northern Central America from the Caribbean at the end of the Eocene, and (3) a wave of

  8. Gene expression

    International Nuclear Information System (INIS)

    Hildebrand, C.E.; Crawford, B.D.; Walters, R.A.; Enger, M.D.

    1983-01-01

    We prepared probes for isolating functional pieces of the metallothionein locus. The probes enabled a variety of experiments, eventually revealing two mechanisms for metallothionein gene expression, the order of the DNA coding units at the locus, and the location of the gene site in its chromosome. Once the switch regulating metallothionein synthesis was located, it could be joined by recombinant DNA methods to other, unrelated genes, then reintroduced into cells by gene-transfer techniques. The expression of these recombinant genes could then be induced by exposing the cells to Zn 2+ or Cd 2+ . We would thus take advantage of the clearly defined switching properties of the metallothionein gene to manipulate the expression of other, perhaps normally constitutive, genes. Already, despite an incomplete understanding of how the regulatory switch of the metallothionein locus operates, such experiments have been performed successfully

  9. Phylogeny and divergence-date estimates of rapid radiations in muroid rodents based on multiple nuclear genes.

    Science.gov (United States)

    Steppan, Scott; Adkins, Ronald; Anderson, Joel

    2004-08-01

    The muroid rodents are the largest superfamily of mammals, containing nearly one third of all mammal species. We report on a phylogenetic study comprising 53 genera sequenced for four nuclear genes, GHR, BRCA1, RAG1, and c-myc, totaling up to 6400 nucleotides. Most relationships among the subfamilies are resolved. All four genes yield nearly identical phylogenies, differing only in five key regions, four of which may represent particularly rapid radiations. Support is very strong for a fundamental division of the mole rats of the subfamilies Spalacinae and Rhizomyinae from all other muroids. Among the other "core" muroids, a rapid radiation led to at least four distinct lineages: Asian Calomyscus, an African clade of at least four endemic subfamilies, including the diverse Nesomyinae of Madagascar, a hamster clade with maximum diversity in the New World, and an Old World clade including gerbils and the diverse Old World mice and rats (Murinae). The Deomyinae, recently removed from the Murinae, is well supported as the sister group to the gerbils (Gerbillinae). Four key regions appear to represent rapid radiations and, despite a large amount of sequence data, remain poorly resolved: the base of the "core" muroids, among the five cricetid (hamster) subfamilies, within a large clade of Sigmodontinae endemic to South America, and among major geographic lineages of Old World Murinae. Because of the detailed taxon sampling within the Murinae, we are able to refine the fossil calibration of a rate-smoothed molecular clock and apply this clock to date key events in muroid evolution. We calculate rate differences among the gene regions and relate those differences to relative contribution of each gene to the support for various nodes. The among-gene variance in support is greatest for the shortest branches. We present a revised classification for this largest but most unsettled mammalian superfamily.

  10. Diversity of Babesia bovis merozoite surface antigen genes in the Philippines.

    Science.gov (United States)

    Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Ybanez, Adrian Patalinghug; Ybanez, Rochelle Haidee Daclan; Perez, Zandro Obligado; Guswanto, Azirwan; Igarashi, Ikuo; Yokoyama, Naoaki

    2014-02-01

    Babesia bovis is the causative agent of fatal babesiosis in cattle. In the present study, we investigated the genetic diversity of B. bovis among Philippine cattle, based on the genes that encode merozoite surface antigens (MSAs). Forty-one B. bovis-positive blood DNA samples from cattle were used to amplify the msa-1, msa-2b, and msa-2c genes. In phylogenetic analyses, the msa-1, msa-2b, and msa-2c gene sequences generated from Philippine B. bovis-positive DNA samples were found in six, three, and four different clades, respectively. All of the msa-1 and most of the msa-2b sequences were found in clades that were formed only by Philippine msa sequences in the respective phylograms. While all the msa-1 sequences from the Philippines showed similarity to those formed by Australian msa-1 sequences, the msa-2b sequences showed similarity to either Australian or Mexican msa-2b sequences. In contrast, msa-2c sequences from the Philippines were distributed across all the clades of the phylogram, although one clade was formed exclusively by Philippine msa-2c sequences. Similarities among the deduced amino acid sequences of MSA-1, MSA-2b, and MSA-2c from the Philippines were 62.2-100, 73.1-100, and 67.3-100%, respectively. The present findings demonstrate that B. bovis populations are genetically diverse in the Philippines. This information will provide a good foundation for the future design and implementation of improved immunological preventive methodologies against bovine babesiosis in the Philippines. The study has also generated a set of data that will be useful for futher understanding of the global genetic diversity of this important parasite. © 2013.

  11. Genome-wide comparative analysis reveals similar types of NBS genes in hybrid Citrus sinensis genome and original Citrus clementine genome and provides new insights into non-TIR NBS genes.

    Directory of Open Access Journals (Sweden)

    Yunsheng Wang

    Full Text Available In this study, we identified and compared nucleotide-binding site (NBS domain-containing genes from three Citrus genomes (C. clementina, C. sinensis from USA and C. sinensis from China. Phylogenetic analysis of all Citrus NBS genes across these three genomes revealed that there are three approximately evenly numbered groups: one group contains the Toll-Interleukin receptor (TIR domain and two different Non-TIR groups in which most of proteins contain the Coiled Coil (CC domain. Motif analysis confirmed that the two groups of CC-containing NBS genes are from different evolutionary origins. We partitioned NBS genes into clades using NBS domain sequence distances and found most clades include NBS genes from all three Citrus genomes. This suggests that three Citrus genomes have similar numbers and types of NBS genes. We also mapped the re-sequenced reads of three pomelo and three mandarin genomes onto the C. sinensis genome. We found that most NBS genes of the hybrid C. sinensis genome have corresponding homologous genes in both pomelo and mandarin genomes. The homologous NBS genes in pomelo and mandarin suggest that the parental species of C. sinensis may contain similar types of NBS genes. This explains why the hybrid C. sinensis and original C. clementina have similar types of NBS genes in this study. Furthermore, we found that sequence variation amongst Citrus NBS genes were shaped by multiple independent and shared accelerated mutation accumulation events among different groups of NBS genes and in different Citrus genomes. Our comparative analyses yield valuable insight into the structure, organization and evolution of NBS genes in Citrus genomes. Furthermore, our comprehensive analysis showed that the non-TIR NBS genes can be divided into two groups that come from different evolutionary origins. This provides new insights into non-TIR genes, which have not received much attention.

  12. Geographic and Research Center Origins of Rice Resistance to Asian Planthoppers and Leafhoppers: Implications for Rice Breeding and Gene Deployment

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    Finbarr G. Horgan

    2017-09-01

    Full Text Available This study examines aspects of virulence to resistant rice varieties among planthoppers and leafhoppers. Using a series of resistant varieties, brown planthopper, Nilaparvata lugens, virulence was assessed in seedlings and early-tillering plants at seven research centers in South and East Asia. Virulence of the whitebacked planthopper, Sogatella furcifera, in Taiwan and the Philippines was also assessed. Phylogenetic analysis of the varieties using single-nucleotide polymorphisms (SNPs indicated a clade of highly resistant varieties from South Asia with two further South Asian clades of moderate resistance. Greenhouse bioassays indicated that planthoppers can develop virulence against multiple resistance genes including genes introgressed from wild rice species. Nilaparvata lugens populations from Punjab (India and the Mekong Delta (Vietnam were highly virulent to a range of key resistance donors irrespective of variety origin. Sogatella furcifera populations were less virulent to donors than N. lugens; however, several genes for resistance to S. furcifera are now ineffective in East Asia. A clade of International Rice Research Institute (IRRI-bred varieties and breeding lines, without identified leafhopper-resistance genes, were highly resistant to the green leafhopper, Nephotettix virescens. Routine phenotyping during breeding programs likely maintains high levels of quantitative resistance to leafhoppers. We discuss these results in the light of breeding and deploying resistant rice in Asia.

  13. Phylogenetic analysis of the core histone doublet and DNA topo II genes of Marseilleviridae: evidence of proto-eukaryotic provenance.

    Science.gov (United States)

    Erives, Albert J

    2017-11-28

    While the genomes of eukaryotes and Archaea both encode the histone-fold domain, only eukaryotes encode the core histone paralogs H2A, H2B, H3, and H4. With DNA, these core histones assemble into the nucleosomal octamer underlying eukaryotic chromatin. Importantly, core histones for H2A and H3 are maintained as neofunctionalized paralogs adapted for general bulk chromatin (canonical H2 and H3) or specialized chromatin (H2A.Z enriched at gene promoters and cenH3s enriched at centromeres). In this context, the identification of core histone-like "doublets" in the cytoplasmic replication factories of the Marseilleviridae (MV) is a novel finding with possible relevance to understanding the origin of eukaryotic chromatin. Here, we analyze and compare the core histone doublet genes from all known MV genomes as well as other MV genes relevant to the origin of the eukaryotic replisome. Using different phylogenetic approaches, we show that MV histone domains encode obligate H2B-H2A and H4-H3 dimers of possible proto-eukaryotic origin. MV core histone moieties form sister clades to each of the four eukaryotic clades of canonical and variant core histones. This suggests that MV core histone moieties diverged prior to eukaryotic neofunctionalizations associated with paired linear chromosomes and variant histone octamer assembly. We also show that MV genomes encode a proto-eukaryotic DNA topoisomerase II enzyme that forms a sister clade to eukaryotes. This is a relevant finding given that DNA topo II influences histone deposition and chromatin compaction and is the second most abundant nuclear protein after histones. The combined domain architecture and phylogenomic analyses presented here suggest that a primitive origin for MV histone genes is a more parsimonious explanation than horizontal gene transfers + gene fusions + sufficient divergence to eliminate relatedness to eukaryotic neofunctionalizations within the H2A and H3 clades without loss of relatedness to each of

  14. The evolution of Dscam genes across the arthropods.

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    Armitage, Sophie A O; Freiburg, Rebecca Y; Kurtz, Joachim; Bravo, Ignacio G

    2012-04-13

    One way of creating phenotypic diversity is through alternative splicing of precursor mRNAs. A gene that has evolved a hypervariable form is Down syndrome cell adhesion molecule (Dscam-hv), which in Drosophila melanogaster can produce thousands of isoforms via mutually exclusive alternative splicing. The extracellular region of this protein is encoded by three variable exon clusters, each containing multiple exon variants. The protein is vital for neuronal wiring where the extreme variability at the somatic level is required for axonal guidance, and it plays a role in immunity where the variability has been hypothesised to relate to recognition of different antigens. Dscam-hv has been found across the Pancrustacea. Additionally, three paralogous non-hypervariable Dscam-like genes have also been described for D. melanogaster. Here we took a bioinformatics approach, building profile Hidden Markov Models to search across species for putative orthologs to the Dscam genes and for hypervariable alternatively spliced exons, and inferring the phylogenetic relationships among them. Our aims were to examine whether Dscam orthologs exist outside the Bilateria, whether the origin of Dscam-hv could lie outside the Pancrustacea, when the Dscam-like orthologs arose, how many alternatively spliced exons of each exon cluster were present in the most common recent ancestor, and how these clusters evolved. Our results suggest that the origin of Dscam genes may lie after the split between the Cnidaria and the Bilateria and supports the hypothesis that Dscam-hv originated in the common ancestor of the Pancrustacea. Our phylogeny of Dscam gene family members shows six well-supported clades: five containing Dscam-like genes and one containing all the Dscam-hv genes, a seventh clade contains arachnid putative Dscam genes. Furthermore, the exon clusters appear to have experienced different evolutionary histories. Dscam genes have undergone independent duplication events in the insects and

  15. The evolution of Dscam genes across the arthropods

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    Armitage Sophie AO

    2012-04-01

    Full Text Available Abstract Background One way of creating phenotypic diversity is through alternative splicing of precursor mRNAs. A gene that has evolved a hypervariable form is Down syndrome cell adhesion molecule (Dscam-hv, which in Drosophila melanogaster can produce thousands of isoforms via mutually exclusive alternative splicing. The extracellular region of this protein is encoded by three variable exon clusters, each containing multiple exon variants. The protein is vital for neuronal wiring where the extreme variability at the somatic level is required for axonal guidance, and it plays a role in immunity where the variability has been hypothesised to relate to recognition of different antigens. Dscam-hv has been found across the Pancrustacea. Additionally, three paralogous non-hypervariable Dscam-like genes have also been described for D. melanogaster. Here we took a bioinformatics approach, building profile Hidden Markov Models to search across species for putative orthologs to the Dscam genes and for hypervariable alternatively spliced exons, and inferring the phylogenetic relationships among them. Our aims were to examine whether Dscam orthologs exist outside the Bilateria, whether the origin of Dscam-hv could lie outside the Pancrustacea, when the Dscam-like orthologs arose, how many alternatively spliced exons of each exon cluster were present in the most common recent ancestor, and how these clusters evolved. Results Our results suggest that the origin of Dscam genes may lie after the split between the Cnidaria and the Bilateria and supports the hypothesis that Dscam-hv originated in the common ancestor of the Pancrustacea. Our phylogeny of Dscam gene family members shows six well-supported clades: five containing Dscam-like genes and one containing all the Dscam-hv genes, a seventh clade contains arachnid putative Dscam genes. Furthermore, the exon clusters appear to have experienced different evolutionary histories. Conclusions Dscam genes have

  16. Reconstruction of family-level phylogenetic relationships within Demospongiae (Porifera using nuclear encoded housekeeping genes.

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    Malcolm S Hill

    Full Text Available Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges.We generated data from each of the four sponge classes (i.e., Calcarea, Demospongiae, Hexactinellida, and Homoscleromorpha, but focused on family-level relationships within demosponges. With data for 21 newly sampled families, our Maximum Likelihood and Bayesian-based approaches recovered previously phylogenetically defined taxa: Keratosa(p, Myxospongiae(p, Spongillida(p, Haploscleromorpha(p (the marine haplosclerids and Democlavia(p. We found conflicting results concerning the relationships of Keratosa(p and Myxospongiae(p to the remaining demosponges, but our results strongly supported a clade of Haploscleromorpha(p+Spongillida(p+Democlavia(p. In contrast to hypotheses based on mitochondrial genome and ribosomal data, nuclear housekeeping gene data suggested that freshwater sponges (Spongillida(p are sister to Haploscleromorpha(p rather than part of Democlavia(p. Within Keratosa(p, we found equivocal results as to the monophyly of Dictyoceratida. Within Myxospongiae(p, Chondrosida and Verongida were monophyletic. A well-supported clade within Democlavia(p, Tetractinellida(p, composed of all sampled members of Astrophorina and Spirophorina (including the only lithistid in our analysis, was consistently revealed as the sister group to all other members of Democlavia(p. Within Tetractinellida(p, we did not recover monophyletic Astrophorina or Spirophorina. Our results also reaffirmed the monophyly of order Poecilosclerida (excluding Desmacellidae and Raspailiidae, and polyphyly of Hadromerida and Halichondrida.These results, using an independent nuclear gene set, confirmed

  17. Reconstruction of family-level phylogenetic relationships within Demospongiae (Porifera) using nuclear encoded housekeeping genes.

    Science.gov (United States)

    Hill, Malcolm S; Hill, April L; Lopez, Jose; Peterson, Kevin J; Pomponi, Shirley; Diaz, Maria C; Thacker, Robert W; Adamska, Maja; Boury-Esnault, Nicole; Cárdenas, Paco; Chaves-Fonnegra, Andia; Danka, Elizabeth; De Laine, Bre-Onna; Formica, Dawn; Hajdu, Eduardo; Lobo-Hajdu, Gisele; Klontz, Sarah; Morrow, Christine C; Patel, Jignasa; Picton, Bernard; Pisani, Davide; Pohlmann, Deborah; Redmond, Niamh E; Reed, John; Richey, Stacy; Riesgo, Ana; Rubin, Ewelina; Russell, Zach; Rützler, Klaus; Sperling, Erik A; di Stefano, Michael; Tarver, James E; Collins, Allen G

    2013-01-01

    Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges. We generated data from each of the four sponge classes (i.e., Calcarea, Demospongiae, Hexactinellida, and Homoscleromorpha), but focused on family-level relationships within demosponges. With data for 21 newly sampled families, our Maximum Likelihood and Bayesian-based approaches recovered previously phylogenetically defined taxa: Keratosa(p), Myxospongiae(p), Spongillida(p), Haploscleromorpha(p) (the marine haplosclerids) and Democlavia(p). We found conflicting results concerning the relationships of Keratosa(p) and Myxospongiae(p) to the remaining demosponges, but our results strongly supported a clade of Haploscleromorpha(p)+Spongillida(p)+Democlavia(p). In contrast to hypotheses based on mitochondrial genome and ribosomal data, nuclear housekeeping gene data suggested that freshwater sponges (Spongillida(p)) are sister to Haploscleromorpha(p) rather than part of Democlavia(p). Within Keratosa(p), we found equivocal results as to the monophyly of Dictyoceratida. Within Myxospongiae(p), Chondrosida and Verongida were monophyletic. A well-supported clade within Democlavia(p), Tetractinellida(p), composed of all sampled members of Astrophorina and Spirophorina (including the only lithistid in our analysis), was consistently revealed as the sister group to all other members of Democlavia(p). Within Tetractinellida(p), we did not recover monophyletic Astrophorina or Spirophorina. Our results also reaffirmed the monophyly of order Poecilosclerida (excluding Desmacellidae and Raspailiidae), and polyphyly of Hadromerida and Halichondrida. These results, using an independent nuclear gene set

  18. What are the consequences of combining nuclear and mitochondrial data for phylogenetic analysis? Lessons from Plethodon salamanders and 13 other vertebrate clades

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    Wiens John J

    2011-10-01

    Full Text Available Abstract Background The use of mitochondrial DNA data in phylogenetics is controversial, yet studies that combine mitochondrial and nuclear DNA data (mtDNA and nucDNA to estimate phylogeny are common, especially in vertebrates. Surprisingly, the consequences of combining these data types are largely unexplored, and many fundamental questions remain unaddressed in the literature. For example, how much do trees from mtDNA and nucDNA differ? How are topological conflicts between these data types typically resolved in the combined-data tree? What determines whether a node will be resolved in favor of mtDNA or nucDNA, and are there any generalities that can be made regarding resolution of mtDNA-nucDNA conflicts in combined-data trees? Here, we address these and related questions using new and published nucDNA and mtDNA data for Plethodon salamanders and published data from 13 other vertebrate clades (including fish, frogs, lizards, birds, turtles, and mammals. Results We find widespread discordance between trees from mtDNA and nucDNA (30-70% of nodes disagree per clade, but this discordance is typically not strongly supported. Despite often having larger numbers of variable characters, mtDNA data do not typically dominate combined-data analyses, and combined-data trees often share more nodes with trees from nucDNA alone. There is no relationship between the proportion of nodes shared between combined-data and mtDNA trees and relative numbers of variable characters or levels of homoplasy in the mtDNA and nucDNA data sets. Congruence between trees from mtDNA and nucDNA is higher on branches that are longer and deeper in the combined-data tree, but whether a conflicting node will be resolved in favor mtDNA or nucDNA is unrelated to branch length. Conflicts that are resolved in favor of nucDNA tend to occur at deeper nodes in the combined-data tree. In contrast to these overall trends, we find that Plethodon have an unusually large number of strongly

  19. Evolution of the MAGUK protein gene family in premetazoan lineages

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    Ruiz-Trillo Iñaki

    2010-04-01

    Full Text Available Abstract Background Cell-to-cell communication is a key process in multicellular organisms. In multicellular animals, scaffolding proteins belonging to the family of membrane-associated guanylate kinases (MAGUK are involved in the regulation and formation of cell junctions. These MAGUK proteins were believed to be exclusive to Metazoa. However, a MAGUK gene was recently identified in an EST survey of Capsaspora owczarzaki, an unicellular organism that branches off near the metazoan clade. To further investigate the evolutionary history of MAGUK, we have undertook a broader search for this gene family using available genomic sequences of different opisthokont taxa. Results Our survey and phylogenetic analyses show that MAGUK proteins are present not only in Metazoa, but also in the choanoflagellate Monosiga brevicollis and in the protist Capsaspora owczarzaki. However, MAGUKs are absent from fungi, amoebozoans or any other eukaryote. The repertoire of MAGUKs in Placozoa and eumetazoan taxa (Cnidaria + Bilateria is quite similar, except for one class that is missing in Trichoplax, while Porifera have a simpler MAGUK repertoire. However, Vertebrata have undergone several independent duplications and exhibit two exclusive MAGUK classes. Three different MAGUK types are found in both M. brevicollis and C. owczarzaki: DLG, MPP and MAGI. Furthermore, M. brevicollis has suffered a lineage-specific diversification. Conclusions The diversification of the MAGUK protein gene family occurred, most probably, prior to the divergence between Metazoa+choanoflagellates and the Capsaspora+Ministeria clade. A MAGI-like, a DLG-like, and a MPP-like ancestral genes were already present in the unicellular ancestor of Metazoa, and new gene members have been incorporated through metazoan evolution within two major periods, one before the sponge-eumetazoan split and another within the vertebrate lineage. Moreover, choanoflagellates have suffered an independent MAGUK

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

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    Kattina Zavala

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

  1. Repurposed transcriptomic data facilitate discovery of innate immunity toll-like receptor (TLR) Genes across Lophotrochozoa.

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    Halanych, Kenneth M; Kocot, Kevin M

    2014-10-01

    The growing volume of genomic data from across life represents opportunities for deriving valuable biological information from data that were initially collected for another purpose. Here, we use transcriptomes collected for phylogenomic studies to search for toll-like receptor (TLR) genes in poorly sampled lophotrochozoan clades (Annelida, Mollusca, Brachiopoda, Phoronida, and Entoprocta) and one ecdysozoan clade (Priapulida). TLR genes are involved in innate immunity across animals by recognizing potential microbial infection. They have an extracellular leucine-rich repeat (LRR) domain connected to a transmembrane domain and an intracellular toll/interleukin-1 receptor (TIR) domain. Consequently, these genes are important in initiating a signaling pathway to trigger defense. We found at least one TLR ortholog in all but two taxa examined, suggesting that a broad array of lophotrochozoans may have innate immune systems similar to those observed in vertebrates and arthropods. Comparison to the SMART database confirmed the presence of both the LRR and the TIR protein motifs characteristic of TLR genes. Because we looked at only one transcriptome per species, discovery of TLR genes was limited for most taxa. However, several TRL-like genes that vary in the number and placement of LRR domains were found in phoronids. Additionally, several contigs contained LRR domains but lacked TIR domains, suggesting they were not TLRs. Many of these LRR-containing contigs had other domains (e.g., immunoglobin) and are likely involved in innate immunity. © 2014 Marine Biological Laboratory.

  2. Identification and molecular characterization of the nicotianamine synthase gene family in bread wheat.

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    Bonneau, Julien; Baumann, Ute; Beasley, Jesse; Li, Yuan; Johnson, Alexander A T

    2016-12-01

    Nicotianamine (NA) is a non-protein amino acid involved in fundamental aspects of metal uptake, transport and homeostasis in all plants and constitutes the biosynthetic precursor of mugineic acid family phytosiderophores (MAs) in graminaceous plant species. Nicotianamine synthase (NAS) genes, which encode enzymes that synthesize NA from S-adenosyl-L-methionine (SAM), are differentially regulated by iron (Fe) status in most plant species and plant genomes have been found to contain anywhere from 1 to 9 NAS genes. This study describes the identification of 21 NAS genes in the hexaploid bread wheat (Triticum aestivum L.) genome and their phylogenetic classification into two distinct clades. The TaNAS genes are highly expressed during germination, seedling growth and reproductive development. Fourteen of the clade I NAS genes were up-regulated in root tissues under conditions of Fe deficiency. Protein sequence analyses revealed the presence of endocytosis motifs in all of the wheat NAS proteins as well as chloroplast, mitochondrial and secretory transit peptide signals in four proteins. These results greatly expand our knowledge of NAS gene families in graminaceous plant species as well as the genetics underlying Fe nutrition in bread wheat. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  3. [Phylogeny of protostome moulting animals (Ecdysozoa) inferred from 18 and 28S rRNA gene sequences].

    Science.gov (United States)

    Petrov, N B; Vladychenskaia, N S

    2005-01-01

    Reliability of reconstruction of phylogenetic relationships within a group of protostome moulting animals was evaluated by means of comparison of 18 and 28S rRNA gene sequences sets both taken separately and combined. Reliability of reconstructions was evaluated by values of the bootstrap support of major phylogenetic tree nodes and by degree of congruence of phylogenetic trees inferred by various methods. By both criteria, phylogenetic trees reconstructed from the combined 18 and 28S rRNA gene sequences were better than those inferred from 18 and 28S sequences taken separately. Results obtained are consistent with phylogenetic hypothesis separating protostome animals into two major clades, moulting Ecdysozoa (Priapulida + Kinorhyncha, Nematoda + Nematomorpha, Onychophora + Tardigrada, Myriapoda + Chelicerata, Crustacea + Hexapoda) and unmoulting Lophotrochozoa (Plathelminthes, Nemertini, Annelida, Mollusca, Echiura, Sipuncula). Clade Cephalorhyncha does not include nematomorphs (Nematomorpha). Conclusion was taken that it is necessary to use combined 18 and 28S data in phylogenetic studies.

  4. Trypanosoma teixeirae: A new species belonging to the T. cruzi clade causing trypanosomosis in an Australian little red flying fox (Pteropus scapulatus).

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    Barbosa, Amanda D; Mackie, John T; Stenner, Robyn; Gillett, Amber; Irwin, Peter; Ryan, Una

    2016-06-15

    Little is known about the genetic diversity and pathogenicity of trypanosomes in Australian bats. Recently a novel trypanosome species was identified in an adult female little red flying fox (Pteropus scapulatus) with clinical and pathological evidence of trypanosomosis. The present study used morphology and molecular methods to demonstrate that this trypanosome is a distinct species and we propose the name Trypanosoma teixeirae sp. n. Morphological comparison showed that its circulating trypomastigotes were significantly different from those of Trypanosoma pteropi and Trypanosoma hipposideri, two species previously described from Australian bats. Genetic information was not available for T. pteropi and T. hipposideri but phylogenetic analyses at the 18S ribosomal RNA (rRNA) and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) loci indicated that T. teixeirae sp. n. was genetically distinct and clustered with other bat-derived trypanosome species within the Trypanosoma cruzi clade. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Tip of the clade on the top of the World—the first fossil Lophopidae (Hemiptera: Fulgoromorpha) from the Palaeocene of Tibet

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    Szwedo, Jacek; Stroiński, Adam; Lin, Qibin

    2015-06-01

    Lophopidae is a family of planthoppers (Hemiptera: Fulgoromorpha) present today in tropical and subtropical zones of the Old World. The most recent taxonomic studies and phylogeny of these insects do not include the extinct representatives. Therefore, each new discovery of a fossil lophopid is of high interest, giving new insights to their evolutionary history and enabling to test the proposed relationships. The recent findings of extinct Lophopidae in Europe, in various Palaeogene deposits, put in doubts their proposed evolutionary and biogeographic scenario. The new fossil from the Palaeocene of Northern Tibet is related to one of the Lophopidae clades, Apia+ group, believed to be the most advanced one, and recently distributed in the recent Sundaland-New Guinea-Queensland area. A new genus and species Gesaris gnapo gen. et sp. n. provide information on early lophopids diversity and relationships and demonstrates the necessity for a revision of the existing hypotheses for the initial diversification and distributional pattern of the Lophopidae.

  6. Antibody responses induced by Japanese whole inactivated vaccines against equine influenza virus (H3N8) belonging to Florida sublineage clade2.

    Science.gov (United States)

    Yamanaka, Takashi; Bannai, Hiroshi; Nemoto, Manabu; Tsujimura, Koji; Kondo, Takashi; Matsumura, Tomio

    2011-04-01

    In 2010, the World Organisation for Animal Health recommended the inclusion of a Florida sublineage clade2 strain of equine influenza virus (H3N8), which is represented by A/equine/Richmond/1/07 (Richmond07), in equine influenza vaccines. Here, we evaluate the antigenic differences between Japanese vaccine strains and Richmond07 by performing hemagglutination inhibition (HI) assays. Ferret antiserum raised to A/equine/La Plata/93 (La Plata93), which is a Japanese vaccine strain, reacted with Richmond07 at a similar titer to La Plata93. Moreover, two hundred racehorses exhibited similar geometric mean HI antibody titers against La Plata93 and Richmond07 (73.1 and 80.8, respectively). Therefore, we can expect the antibody induced by the current Japanese vaccines to provide some protection against Richmond07-like viruses.

  7. Phylogenetic relationships in Taxodiaceae and Cupressaceae sensu stricto based on matK gene, chlL gene, trnL-trnF IGS region, and trnL intron sequences.

    Science.gov (United States)

    Kusumi, J; Tsumura, Y; Yoshimaru, H; Tachida, H

    2000-10-01

    Nucleotide sequences from four chloroplast genes, the matK, chlL, intergenic spacer (IGS) region between trnL and trnF, and an intron of trnL, were determined from all species of Taxodiaceae and five species of Cupressaceae sensu stricto (s.s.). Phylogenetic trees were constructed using the maximum parsimony and the neighbor-joining methods with Cunninghamia as an outgroup. These analyses provided greater resolution of relationships among genera and higher bootstrap supports for clades compared to previous analyses. Results indicate that Taiwania diverged first, and then Athrotaxis diverged from the remaining genera. Metasequoia, Sequoia, and Sequoiadendron form a clade. Taxodium and Glyptostrobus form a clade, which is the sister to Cryptomeria. Cupressaceae s.s. are derived from within Taxodiaceae, being the most closely related to the Cryptomeria/Taxodium/Glyptostrobus clade. These relationships are consistent with previous morphological groupings and the analyses of molecular data. In addition, we found acceleration of evolutionary rates in Cupressaceae s.s. Possible causes for the acceleration are discussed.

  8. Highly Pathogenic Avian Influenza H5N8 Clade 2.3.4.4b in Germany in 2016/2017

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    Anja Globig

    2018-01-01

    Full Text Available Here, we report on the occurrence of highly pathogenic avian influenza (HPAI H5Nx clade 2.3.4.4b in Germany. Between November 8, 2016, and September 30, 2017, more than 1,150 cases of HPAI H5Nx clade 2.3.4.4b in wild birds and 107 outbreaks in birds kept in captivity (92 poultry holdings and 15 zoos/animal parks were reported in Germany. This HPAI epidemic is the most severe recorded in Germany so far. The viruses were apparently introduced by migratory birds, sparking an epidemic among wild birds across Germany with occasional incursions into poultry holdings, zoos and animal parks, which were usually rapidly detected and controlled by stamping out. HPAI viruses (mainly subtype H5N8, in a few cases also H5N5 were found in dead wild birds of at least 53 species. The affected wild birds were water birds (including gulls, storks, herons, and cormorants and scavenging birds (birds of prey, owls, and crows. In a number of cases, substantial gaps in farm biosecurity may have eased virus entry into the holdings. In a second wave of the epidemic starting from February 2017, there was epidemiological and molecular evidence for virus transmission of the infections between commercial turkey holdings in an area of high poultry density, which caused approximately 25% of the total number of outbreaks in poultry. Biosecurity measures in poultry holdings should be adapted. This includes, inter alia, wearing of stable-specific protective clothing and footwear, cleaning, and disinfection of equipment that has been in contact with birds and prevention of contacts between poultry and wild water birds.

  9. Ecuador Paraiso Escondido Virus, a New Flavivirus Isolated from New World Sand Flies in Ecuador, Is the First Representative of a Novel Clade in the Genus Flavivirus.

    Science.gov (United States)

    Alkan, Cigdem; Zapata, Sonia; Bichaud, Laurence; Moureau, Grégory; Lemey, Philippe; Firth, Andrew E; Gritsun, Tamara S; Gould, Ernest A; de Lamballerie, Xavier; Depaquit, Jérôme; Charrel, Rémi N

    2015-12-01

    A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies (Psathyromyia abonnenci, formerly Lutzomyia abonnenci) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogenetic analysis of the complete coding sequence showed that EPEV represents a distinct clade which diverged from a lineage that was ancestral to the nonvectored flaviviruses Entebbe bat virus, Yokose virus, and Sokoluk virus and also the Aedes-associated mosquito-borne flaviviruses, which include yellow fever virus, Sepik virus, Saboya virus, and others. EPEV replicated in C6/36 mosquito cells, yielding high infectious titers, but failed to reproduce either in vertebrate cell lines (Vero, BHK, SW13, and XTC cells) or in suckling mouse brains. This surprising result, which appears to eliminate an association with vertebrate hosts in the life cycle of EPEV, is discussed in the context of the evolutionary origins of EPEV in the New World. The flaviviruses are rarely (if ever) vectored by sand fly species, at least in the Old World. We have identified the first representative of a sand fly-associated flavivirus, Ecuador Paraiso Escondido virus (EPEV), in the New World. EPEV constitutes a novel clade according to current knowledge of the flaviviruses. Phylogenetic analysis of the virus genome showed that EPEV roots the Aedes-associated mosquito-borne flaviviruses, including yellow fever virus. In light of this new discovery, the New World origin of EPEV is discussed together with that of the other flaviviruses. Copyright © 2015 Alkan et al.

  10. Sequence analysis of the internal transcribed spacer (ITS) region reveals a novel clade of Ichthyophonus sp. from rainbow trout.

    Science.gov (United States)

    Rasmussen, C; Purcell, M K; Gregg, J L; LaPatra, S E; Winton, J R; Hershberger, P K

    2010-03-09

    The mesomycetozoean parasite Ichthyophonus hoferi is most commonly associated with marine fish hosts but also occurs in some components of the freshwater rainbow trout Oncorhynchus mykiss aquaculture industry in Idaho, USA. It is not certain how the parasite was introduced into rainbow trout culture, but it might have been associated with the historical practice of feeding raw, ground common carp Cyprinus carpio that were caught by commercial fisherman. Here, we report a major genetic division between west coast freshwater and marine isolates of Ichthyophonus hoferi. Sequence differences were not detected in 2 regions of the highly conserved small subunit (18S) rDNA gene; however, nucleotide variation was seen in internal transcribed spacer loci (ITS1 and ITS2), both within and among the isolates. Intra-isolate variation ranged from 2.4 to 7.6 nucleotides over a region consisting of approximately 740 bp. Majority consensus sequences from marine/anadromous hosts differed in only 0 to 3 nucleotides (99.6 to 100% nucleotide identity), while those derived from freshwater rainbow trout had no nucleotide substitutions relative to each other. However, the consensus sequences between isolates from freshwater rainbow trout and those from marine/anadromous hosts differed in 13 to 16 nucleotides (97.8 to 98.2% nucleotide identity).

  11. Rapid duplication and loss of nbs-encoding genes in eurosids II

    International Nuclear Information System (INIS)

    Si, W.; Gu, L.; Yang, S.; Zhang, X.; Memon, S.

    2015-01-01

    Eurosids basically evolved from the core Eudicots Rosids. The Rosids consist of two large assemblages, Eurosids I (Fabids) and Eurosids II (Malvids), which belong to the largest group of Angiosperms, comprising of >40,000 and ∼ 15,000 species, respectively. Although the evolutionary patterns of the largest class of disease resistance genes consisting of a nucleotide binding site (NBS) and leucine-rich repeats (LRRs) have been studied in many species, systemic research of NBS-encoding genes has not been performed in different orders of Eurosids II. Here, five Eurosids II species, Gossypium raimondii, Theobroma cacao, Carica papaya, Citrus clementina, and Arabidopsis thaliana, distributing in three orders, were used to gain insights into the evolutionary patterns of the NBS-encoding genes. Our data showed that frequent copy number variations of NBS-encoding genes were found among these species. Phylogenetic tree analysis and the numbers of the NBS-encoding genes in the common ancestor of these species showed that species-specific NBS clades, including multi-copy and single copy numbers are dominant among these genes. However, not a single clade was found with only five copies, which come from all of the five species, respectively, suggesting rapid turn-over with birth and death of the NBS-encoding genes among Eurosids II species. In addition, a strong positive correlation was observed between the Toll/interleukin receptor (TIR)) type NBS-encoding genes and species-specific genes, indicating rapid gene loss and duplication. Whereas, non- TIR type NBS-encoding genes in these five species showed two distinct evolutionary patterns. (author)

  12. Highlighting of quorum sensing lux genes and their expression in the hydrothermal vent shrimp Rimicaris exoculata ectosymbiontic community. Possible use as biogeographic markers.

    Directory of Open Access Journals (Sweden)

    Simon Le Bloa

    Full Text Available Rimicaris exoculata is a caridean shrimp that dominates the fauna at several hydrothermal vent sites of the Mid-Atlantic Ridge. It has two distinct and stable microbial communities. One of these epibiontic bacterial communities is located in the shrimp gut and has a distribution and role that are poorly understood. The second colonizes its enlarged gill chamber and is involved in host nutrition. It is eliminated after each molt, and has colonization processes reminiscent of those of a biofilm. The presence and expression of genes usually involved in quorum sensing (QS were then studied. At four sites, Rainbow, TAG, Snake Pit and Logatchev, two lux genes were identified in the R. exoculata epibiontic community at different shrimp molt stages and life stages. RT-PCR experiments highlighted lux gene expression activity at TAG, Snake Pit and Rainbow vent sites. Their potential QS activity and their possible roles in epibiont colonization processes are discussed. Moreover, phylogenetic analysis has shown the presence of three clades for luxS (Epsilonproteobacteria and four clades for luxR (Gammaproteobacteria genes, each clade being restricted to a single site. These genes are more divergent than the 16S rRNA one. They could therefore be used as biogeographical genetic markers.

  13. Gene arrangement and sequence of mitochondrial genomes yield insights into the phylogeny and evolution of bees and sphecid wasps (Hymenoptera: Apoidea).

    Science.gov (United States)

    Zheng, Bo-Ying; Cao, Li-Jun; Tang, Pu; van Achterberg, Kees; Hoffmann, Ary A; Chen, Hua-Yan; Chen, Xue-Xin; Wei, Shu-Jun

    2018-07-01

    The Apoidea represent a large and common superfamily of the Hymenoptera including the bees and sphecid wasps. A robust phylogenetic tree is essential to understanding the diversity, taxonomy and evolution of the Apoidea. In this study, features of apoid mitochondrial genomes were used to reconstruct phylogenetic relationships. Twelve apoid mitochondrial genomes were newly sequenced, representing six families and nine subfamilies. Gene rearrangement events have occurred in all apoid mitochondrial genomes sequenced to date. Sphecid wasps have both tRNA and protein-coding gene rearrangements in 5 of 8 species. In bees, the only rearranged genes are tRNAs; long-tongued bees (Apidae + Megachilidae) are characterized by movement of trnA to the trnI-trnQ-trnM tRNA cluster. Phylogenetic analyses of mitochondrial gene sequences support the known paraphyly of sphecid wasps, with bees nested within this clade. The Ampulicidae is sister to the remaining Apoidea. Crabronidae is paraphyletic, split into Crabronidae s.s. and Philanthidae, with the latter group a sister clade to bees. The monophyletic bees are either classified into two clades, long-tongued bees (Apidae + Megachilidae) and short-tongued bees (Andrenidae + Halictidae + Colletidae + Melitidae), or three groups with the Melitidae sister to the other bees. Our study showed that both gene sequences and arrangements provide information on the phylogeny of apoid families. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Trichoderma genes

    Science.gov (United States)

    Foreman, Pamela [Los Altos, CA; Goedegebuur, Frits [Vlaardingen, NL; Van Solingen, Pieter [Naaldwijk, NL; Ward, Michael [San Francisco, CA

    2012-06-19

    Described herein are novel gene sequences isolated from Trichoderma reesei. Two genes encoding proteins comprising a cellulose binding domain, one encoding an arabionfuranosidase and one encoding an acetylxylanesterase are described. The sequences, CIP1 and CIP2, contain a cellulose binding domain. These proteins are especially useful in the textile and detergent industry and in pulp and paper industry.

  15. Cucumis sativus L-type lectin receptor kinase (CsLecRK) gene family response to Phytophthora melonis, Phytophthora capsici and water immersion in disease resistant and susceptible cucumber cultivars.

    Science.gov (United States)

    Wu, Tingquan; Wang, Rui; Xu, Xiaomei; He, Xiaoming; Sun, Baojuan; Zhong, Yujuan; Liang, Zhaojuan; Luo, Shaobo; Lin, Yu'e

    2014-10-10

    L-type lectin receptor kinase (LecRK) proteins are an important family involved in diverse biological processes such as pollen development, senescence, wounding, salinity and especially in innate immunity in model plants such as Arabidopsis and tobacco. Till date, LecRK proteins or genes of cucumber have not been reported. In this study, a total of 25 LecRK genes were identified in the cucumber genome, unequally distributed across its seven chromosomes. According to similarity comparison of their encoded proteins, the Cucumis sativus LecRK (CsLecRK) genes were classified into six major clades (from Clade I to CladeVI). Expression of CsLecRK genes were tested using QRT-PCR method and the results showed that 25 CsLecRK genes exhibited different responses to abiotic (water immersion) and biotic (Phytophthora melonis and Phytophthora capsici inoculation) stresses, as well as that between disease resistant cultivar (JSH) and disease susceptible cultivar (B80). Among the 25 CsLecRK genes, we found CsLecRK6.1 was especially induced by P. melonis and P. capsici in JSH plants. All these results suggested that CsLecRK genes may play important roles in biotic and abiotic stresses. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. A fungal phylogeny based on 42 complete genomes derived from supertree and combined gene analysis

    Directory of Open Access Journals (Sweden)

    Stajich Jason E

    2006-11-01

    Full Text Available Abstract Background To date, most fungal phylogenies have been derived from single gene comparisons, or from concatenated alignments of a small number of genes. The increase in fungal genome sequencing presents an opportunity to reconstruct evolutionary events using entire genomes. As a tool for future comparative, phylogenomic and phylogenetic studies, we used both supertrees and concatenated alignments to infer relationships between 42 species of fungi for which complete genome sequences are available. Results A dataset of 345,829 genes was extracted from 42 publicly available fungal genomes. Supertree methods were employed to derive phylogenies from 4,805 single gene families. We found that the average consensus supertree method may suffer from long-branch attraction artifacts, while matrix representation with parsimony (MRP appears to be immune from these. A genome phylogeny was also reconstructed from a concatenated alignment of 153 universally distributed orthologs. Our MRP supertree and concatenated phylogeny are highly congruent. Within the Ascomycota, the sub-phyla Pezizomycotina and Saccharomycotina were resolved. Both phylogenies infer that the Leotiomycetes are the closest sister group to the Sordariomycetes. There is some ambiguity regarding the placement of Stagonospora nodurum, the sole member of the class Dothideomycetes present in the dataset. Within the Saccharomycotina, a monophyletic clade containing organisms that translate CTG as serine instead of leucine is evident. There is also strong support for two groups within the CTG clade, one containing the fully sexual species Candida lusitaniae, Candida guilliermondii and Debaryomyces hansenii, and the second group containing Candida albicans, Candida dubliniensis, Candida tropicalis, Candida parapsilosis and Lodderomyces elongisporus. The second major clade within the Saccharomycotina contains species whose genomes have undergone a whole genome duplication (WGD, and their close

  17. Rooting gene trees without outgroups: EP rooting.

    Science.gov (United States)

    Sinsheimer, Janet S; Little, Roderick J A; Lake, James A

    2012-01-01

    Gene sequences are routinely used to determine the topologies of unrooted phylogenetic trees, but many of the most important questions in evolution require knowing both the topologies and the roots of trees. However, general algorithms for calculating rooted trees from gene and genomic sequences in the absence of gene paralogs are few. Using the principles of evolutionary parsimony (EP) (Lake JA. 1987a. A rate-independent technique for analysis of nucleic acid sequences: evolutionary parsimony. Mol Biol Evol. 4:167-181) and its extensions (Cavender, J. 1989. Mechanized derivation of linear invariants. Mol Biol Evol. 6:301-316; Nguyen T, Speed TP. 1992. A derivation of all linear invariants for a nonbalanced transversion model. J Mol Evol. 35:60-76), we explicitly enumerate all linear invariants that solely contain rooting information and derive algorithms for rooting gene trees directly from gene and genomic sequences. These new EP linear rooting invariants allow one to determine rooted trees, even in the complete absence of outgroups and gene paralogs. EP rooting invariants are explicitly derived for three taxon trees, and rules for their extension to four or more taxa are provided. The method is demonstrated using 18S ribosomal DNA to illustrate how the new animal phylogeny (Aguinaldo AMA et al. 1997. Evidence for a clade of nematodes, arthropods, and other moulting animals. Nature 387:489-493; Lake JA. 1990. Origin of the metazoa. Proc Natl Acad Sci USA 87:763-766) may be rooted directly from sequences, even when they are short and paralogs are unavailable. These results are consistent with the current root (Philippe H et al. 2011. Acoelomorph flatworms are deuterostomes related to Xenoturbella. Nature 470:255-260).

  18. Combining phylogenetic and syntenic analyses for understanding the evolution of TCP ECE genes in eudicots.

    Directory of Open Access Journals (Sweden)

    Hélène L Citerne

    Full Text Available TCP ECE genes encode transcription factors which have received much attention for their repeated recruitment in the control of floral symmetry in core eudicots, and more recently in monocots. Major duplications of TCP ECE genes have been described in core eudicots, but the evolutionary history of this gene family is unknown in basal eudicots. Reconstructing the phylogeny of ECE genes in basal eudicots will help set a framework for understanding the functional evolution of these genes. TCP ECE genes were sequenced in all major lineages of basal eudicots and Gunnera which belongs to the sister clade to all other core eudicots. We show that in these lineages they have a complex evolutionary history with repeated duplications. We estimate the timing of the two major duplications already identified in the core eudicots within a timeframe before the divergence of Gunnera and after the divergence of Proteales. We also use a synteny-based approach to examine the extent to which the expansion of TCP ECE genes in diverse eudicot lineages may be due to genome-wide duplications. The three major core-eudicot specific clades share a number of collinear genes, and their common evolutionary history may have originated at the γ event. Genomic comparisons in Arabidopsis thaliana and Solanumlycopersicum highlight their separate polyploid origin, with syntenic fragments with and without TCP ECE genes showing differential gene loss and genomic rearrangements. Comparison between recently available genomes from two basal eudicots Aquilegiacoerulea and Nelumbonucifera suggests that the two TCP ECE paralogs in these species are also derived from large-scale duplications. TCP ECE loci from basal eudicots share many features with the three main core eudicot loci, and allow us to infer the makeup of the ancestral eudicot locus.

  19. A Δ11 desaturase gene genealogy reveals two divergent allelic classes within the European corn borer (Ostrinia nubilalis

    Directory of Open Access Journals (Sweden)

    Harrison Richard G

    2010-04-01

    Full Text Available Abstract Background Moth pheromone mating systems have been characterized at the molecular level, allowing evolutionary biologists to study how changes in protein sequence or gene expression affect pheromone phenotype, patterns of mating, and ultimately, the formation of barriers to gene exchange. Recent studies of Ostrinia pheromones have focused on the diversity of sex pheromone desaturases and their role in the specificity of pheromone production. Here we produce a Δ11 desaturase genealogy within Ostrinia nubilalis. We ask what has been the history of this gene, and whether this history suggests that changes in Δ11 desaturase have been involved in the divergence of the E and Z O. nubilalis pheromone strains. Results The Δ11 desaturase gene genealogy does not differentiate O. nubilalis pheromone strains. However, we find two distinct clades, separated by 2.9% sequence divergence, that do not sort with pheromone strain, geographic origin, or emergence time. We demonstrate that these clades do not represent gene duplicates, but rather allelic variation at a single gene locus. Conclusions Analyses of patterns of variation at the Δ11 desaturase gene in ECB suggest that this enzyme does not contribute to reproductive isolation between pheromone strains (E and Z. However, our genealogy reveals two deeply divergent allelic classes. Standing variation at loci that contribute to mate choice phenotypes may permit novel pheromone mating systems to arise in the presence of strong stabilizing selection.

  20. Positive selection and ancient duplications in the evolution of class B floral homeotic genes of orchids and grasses

    Directory of Open Access Journals (Sweden)

    Koch Marcus A

    2009-04-01

    Full Text Available Abstract Background Positive selection is recognized as the prevalence of nonsynonymous over synonymous substitutions in a gene. Models of the functional evolution of duplicated genes consider neofunctionalization as key to the retention of paralogues. For instance, duplicate transcription factors are specifically retained in plant and animal genomes and both positive selection and transcriptional divergence appear to have played a role in their diversification. However, the relative impact of these two factors has not been systematically evaluated. Class B MADS-box genes, comprising DEF-like and GLO-like genes, encode developmental transcription factors essential for establishment of perianth and male organ identity in the flowers of angiosperms. Here, we contrast the role of positive selection and the known divergence in expression patterns of genes encoding class B-like MADS-box transcription factors from monocots, with emphasis on the family Orchidaceae and the order Poales. Although in the monocots these two groups are highly diverse and have a strongly canalized floral morphology, there is no information on the role of positive selection in the evolution of their distinctive flower morphologies. Published research shows that in Poales, class B-like genes are expressed in stamens and in lodicules, the perianth organs whose identity might also be specified by class B-like genes, like the identity of the inner tepals of their lily-like relatives. In orchids, however, the number and pattern of expression of class B-like genes have greatly diverged. Results The DEF-like genes from Orchidaceae form four well-supported, ancient clades of orthologues. In contrast, orchid GLO-like genes form a single clade of ancient orthologues and recent paralogues. DEF-like genes from orchid clade 2 (OMADS3-like genes are under less stringent purifying selection than the other orchid DEF-like and GLO-like genes. In comparison with orchids, purifying selection

  1. Evaluation of immunological cross-reactivity between clade A9 high-risk human papillomavirus types on the basis of E6-Specific CD4+ memory T cell responses

    NARCIS (Netherlands)

    van den Hende, Muriel; Redeker, Anke; Kwappenberg, Kitty M. C.; Franken, Kees L. M. C.; Drijfhout, Jan W.; Oostendorp, Jaap; Valentijn, A. Rob P. M.; Fathers, Loraine M.; Welters, Marij J. P.; Melief, Cornelis J. M.; Kenter, Gemma G.; van der Burg, Sjoerd H.; Offringa, Rienk

    2010-01-01

    CD4(+) T cell responses against the E6 oncoprotein of human papillomavirus (HPV) type 16 and 5 closely related members of clade A9 (HPV31, 33, 35, 52, and 58) were charted in peripheral blood mononuclear cell cultures from healthy subjects and patients who underwent HPV16 E6/E7-specific vaccination.

  2. HIV controllers exhibit enhanced frequencies of major histocompatibility complex class II tetramer+ Gag-specific CD4+ T cells in chronic clade C HIV-1 infection

    DEFF Research Database (Denmark)

    Laher, Faatima; Ranasinghe, Srinika; Porichis, Filippos

    2017-01-01

    Immune control of viral infections is heavily dependent on helper CD4+ T cell function. However, the understanding of the contribution of HIV-specific CD4+ T cell responses to immune protection against HIV-1, particularly in clade C infection, remains incomplete. Recently, major histocompatibilit...

  3. Ageing genes

    DEFF Research Database (Denmark)

    Rattan, Suresh

    2018-01-01

    The idea of gerontogenes is in line with the evolutionary explanation of ageing as being an emergent phenomenon as a result of the imperfect maintenance and repair systems. Although evolutionary processes did not select for any specific ageing genes that restrict and determine the lifespan...... of an individual, the term ‘gerontogenes’ primarily refers to any genes that may seem to influence ageing and longevity, without being specifically selected for that role. Such genes can also be called ‘virtual gerontogenes’ by virtue of their indirect influence on the rate and process of ageing. More than 1000...... virtual gerontogenes have been associated with ageing and longevity in model organisms and humans. The ‘real’ genes, which do influence the essential lifespan of a species, and have been selected for in accordance with the evolutionary life history of the species, are known as the longevity assurance...

  4. Patterns and Implications of Gene Gain and Loss in the Evolution of Prochlorococcus

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, Alla; Kettler, Gregory C.; Martiny, Adam C.; Huang, Katherine; Zucker, Jeremy; Coleman, Maureen L.; Rodrigue, Sebastien; Chen, Feng; Lapidus, Alla; Ferriera, Steven; Johnson, Justin; Steglich, Claudia; Church, George M.; Richardson, Paul; Chisholm, Sallie W.

    2007-07-30

    Prochlorococcus is a marine cyanobacterium that numerically dominates the mid-latitude oceans and is the smallest known oxygenic phototroph. Numerous isolatesfrom diverse areas of the world's oceans have been studied and shown to be physiologically and genetically distinct. All isolates described thus far can be assigned to either a tightly clustered high-light (HL)-adapted clade, or a more divergent low-light (LL)-adapted group. The 16S rRNA sequences of the entire Prochlorococcus group differ by at most 3percent, and the four initially published genomes revealed patterns of genetic differentiation that help explain physiological differences among the isolates. Here we describe the genomes of eight newly sequenced isolates and combine them with the first four genomes for a comprehensive analysis of the core (shared by all isolates) and flexible genes of the Prochlorococcus group, and the patterns of loss and gain of the flexible genes over the course of evolution. There are 1,273 genes that represent the core shared by all 12 genomes. They are apparently sufficient, according to metabolic reconstruction, to encode a functional cell. We describe a phylogeny for all 12 isolates by subjecting their complete proteomes to three different phylogenetic analyses. For each non-core gene, we used a maximum parsimony method to estimate which ancestor likely first acquired or lost each gene. Many of the genetic differences among isolates, especially for genes involved in outer membrane synthesis and nutrient transport, are found within the same clade. Nevertheless, we identified some genes defining HL and LL ecotypes, and clades within these broad ecotypes, helping to demonstrate the basis of HL and LL adaptations in Prochlorococcus. Furthermore, our estimates of gene gain events allow us to identify highly variable genomic islands that are not apparent through simple pairwise comparisons. These results emphasize the functional roles, especially those connected to outer

  5. Patterns and implications of gene gain and loss in the evolution of Prochlorococcus.

    Directory of Open Access Journals (Sweden)

    Gregory C Kettler

    2007-12-01

    Full Text Available Prochlorococcus is a marine cyanobacterium that numerically dominates the mid-latitude oceans and is the smallest known oxygenic phototroph. Numerous isolates from diverse areas of the world's oceans have been studied and shown to be physiologically and genetically distinct. All isolates described thus far can be assigned to either a tightly clustered high-light (HL-adapted clade, or a more divergent low-light (LL-adapted group. The 16S rRNA sequences of the entire Prochlorococcus group differ by at most 3%, and the four initially published genomes revealed patterns of genetic differentiation that help explain physiological differences among the isolates. Here we describe the genomes of eight newly sequenced isolates and combine them with the first four genomes for a comprehensive analysis of the core (shared by all isolates and flexible genes of the Prochlorococcus group, and the patterns of loss and gain of the flexible genes over the course of evolution. There are 1,273 genes that represent the core shared by all 12 genomes. They are apparently sufficient, according to metabolic reconstruction, to encode a functional cell. We describe a phylogeny for all 12 isolates by subjecting their complete proteomes to three different phylogenetic analyses. For each non-core gene, we used a maximum parsimony method to estimate which ancestor likely first acquired or lost each gene. Many of the genetic differences among isolates, especially for genes involved in outer membrane synthesis and nutrient transport, are found within the same clade. Nevertheless, we identified some genes defining HL and LL ecotypes, and clades within these broad ecotypes, helping to demonstrate the basis of HL and LL adaptations in Prochlorococcus. Furthermore, our estimates of gene gain events allow us to identify highly variable genomic islands that are not apparent through simple pairwise comparisons. These results emphasize the functional roles, especially those connected to

  6. Allotetraploid origin and divergence in Eleusine (Chloridoideae, Poaceae): evidence from low-copy nuclear gene phylogenies and a plastid gene chronogram.

    Science.gov (United States)

    Liu, Qing; Triplett, Jimmy K; Wen, Jun; Peterson, Paul M

    2011-11-01

    Eleusine (Poaceae) is a small genus of the subfamily Chloridoideae exhibiting considerable morphological and ecological diversity in East Africa and the Americas. The interspecific phylogenetic relationships of Eleusine are investigated in order to identify its allotetraploid origin, and a chronogram is estimated to infer temporal relationships between palaeoenvironment changes and divergence of Eleusine in East Africa. Two low-copy nuclear (LCN) markers, Pepc4 and EF-1α, were analysed using parsimony, likelihood and Bayesian approaches. A chronogram of Eleusine was inferred from a combined data set of six plastid DNA markers (ndhA intron, ndhF, rps16-trnK, rps16 intron, rps3, and rpl32-trnL) using the Bayesian dating method. The monophyly of Eleusine is strongly supported by sequence data from two LCN markers. In the cpDNA phylogeny, three tetraploid species (E. africana, E. coracana and E. kigeziensis) share a common ancestor with the E. indica-E. tristachya clade, which is considered a source of maternal parents for allotetraploids. Two homoeologous loci are isolated from three tetraploid species in the Pepc4 phylogeny, and the maternal parents receive further support. The A-type EF-1α sequences possess three characters, i.e. a large number of variations of intron 2; clade E-A distantly diverged from clade E-B and other diploid species; and seven deletions in intron 2, implying a possible derivation through a gene duplication event. The crown age of Eleusine and the allotetraploid lineage are 3·89 million years ago (mya) and 1·40 mya, respectively. The molecular data support independent allotetraploid origins for E. kigeziensis and the E. africana-E. coracana clade. Both events may have involved diploids E. indica and E. tristachya as the maternal parents, but the paternal parents remain unidentified. The habitat-specific hypothesis is proposed to explain the divergence of Eleusine and its allotetraploid lineage.

  7. Is evolutionary biology becoming too politically correct? A reflection on the scala naturae, phylogenetically basal clades, anatomically plesiomorphic taxa, and 'lower' animals.

    Science.gov (United States)

    Diogo, Rui; Ziermann, Janine M; Linde-Medina, Marta

    2015-05-01

    The notion of scala naturae dates back to thinkers such as Aristotle, who placed plants below animals and ranked the latter along a graded scale of complexity from 'lower' to 'higher' animals, such as humans. In the last decades, evolutionary biologists have tended to move from one extreme (i.e. the idea of scala naturae or the existence of a general evolutionary trend in complexity from 'lower' to "higher" taxa, with Homo sapiens as the end stage) to the other, opposite, extreme (i.e. to avoid using terms such as 'phylogenetically basal' and 'anatomically plesiomorphic' taxa, which are seen as the undesired vestige of old teleological theories). The latter view tries to avoid any possible connotations with the original anthropocentric idea of a scala naturae crowned by man and, in that sense, it can be regarded as a more politically correct view. In the past years and months there has been renewed interest in these topics, which have been discussed in various papers and monographs that tend to subscribe, in general, to the points defended in the more politically correct view. Importantly, most evolutionary and phylogenetic studies of tetrapods and other vertebrates, and therefore most discussions on the scala naturae and related issues have been based on hard tissue and, more recently, on molecular data. Here we provide the first discussion of these topics based on a comparative myological study of all the major vertebrate clades and of myological cladistic and Bayesian phylogenetic analyses of bony fish and tetrapods, including Primates. We specifically (i) contradict the notions of a scala naturae or evolutionary progressive trends leading to more complexity in 'higher' animals and culminating in Homo sapiens, and (ii) stress that the refutation of these old notions does not necessarily mean that one should not keep using the terms 'phylogenetically basal' and particularly 'anatomically plesiomorphic' to refer to groups such as the urodeles within the Tetrapoda

  8. A phylogenetic analysis of the genus Psathyrostachys (Poaceae) based on one nuclear gene, three plastid genes, and morphology

    DEFF Research Database (Denmark)

    Petersen, Gitte; Seberg, Ole; Baden, Claus

    2004-01-01

    A phylogenetic analysis of the small, Central Asian genus Psathyrostachys Nevski is presented. The analysis is based on morphological characters and nucleotide sequence data from one nuclear gene, DMC1, and three plastid genes, rbcL, rpoA, and rpoC2. Separate analyses of the three data partitions...... (morphology, nuclear sequences, and plastid sequences) result in mostly congruent trees. The plastid and nuclear sequences produce completely congruent trees, and only the trees based on plastid sequences and morphological characters are incongruent. Combined analysis of all data results in a fairly well......-resolved strict consensus tree: Ps. rupestris is the sister to the remaining species, which are divided into two clades: one including Ps. fragilis and Ps. caduca, the other including Ps. juncea, Ps. huashanica, Ps. lanuginosa, Ps. stoloniformis, and Ps. kronenburgii. Pubescent culms and more than 20 mm long...

  9. Prolonged Adaptive Evolution of a Defensive Gene in the Solanaceae.

    Science.gov (United States)

    Rausher, Mark D; Huang, Jie

    2016-01-01

    Although plants and their natural enemies may coevolve for prolonged periods, little is known about how long individual plant defensive genes are involved in the coevolutionary process. We address this issue by examining patterns of selection on the defensive gene threonine deaminase (TD). Tomato (Solanum lycopersicum) has two copies of this gene. One performs the canonical housekeeping function in amino acid metabolism of catalyzing the first reaction in the conversion of threonine to isoleucine. The second copy functions as an antinutritive defense against lepidopteran herbivores by depleting threonine in the insect gut. Wild tobacco (Nicotiana attenuata) also contains a defensive copy. We show that a single copy of TD underwent two or three duplications near the base of the Solanaceae. One copy retains the housekeeping function, whereas a second copy evolved defensive functions. Positive selection occurred on the branch of the TD2 gene tree subtending the common ancestor of the Nicotianoideae and Solanoideae. It also occurred within the Solanoideae clade but not within the Nicotianoideae clade. Finally, it occurred on most branches leading from the common ancestor to S. lycopersicum. Based on recent calibrations of the Solanaceae phylogeny, TD2 experienced adaptive substitutions for a period of 30-50 My. We suggest that the most likely explanation for this result is fluctuating herbivore abundances: When herbivores are rare, relaxed selection increases the likelihood that slightly disadvantageous mutations will be fixed by drift; when herbivores are common, increased selection causes the evolution of compensatory adaptive mutations. Alternative explanations are also discussed. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. The evolution of pepsinogen C genes in vertebrates: duplication, loss and functional diversification.

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    Luís Filipe Costa Castro

    Full Text Available BACKGROUND: Aspartic proteases comprise a large group of enzymes involved in peptide proteolysis. This collection includes prominent enzymes globally categorized as pepsins, which are derived from pepsinogen precursors. Pepsins are involved in gastric digestion, a hallmark of vertebrate physiology. An important member among the pepsinogens is pepsinogen C (Pgc. A particular aspect of Pgc is its apparent single copy status, which contrasts with the numerous gene copies found for example in pepsinogen A (Pga. Although gene sequences with similarity to Pgc have been described in some vertebrate groups, no exhaustive evolutionary framework has been considered so far. METHODOLOGY/PRINCIPAL FINDINGS: By combining phylogenetics and genomic analysis, we find an unexpected Pgc diversity in the vertebrate sub-phylum. We were able to reconstruct gene duplication timings relative to the divergence of major vertebrate clades. Before tetrapod divergence, a single Pgc gene tandemly expanded to produce two gene lineages (Pgbc and Pgc2. These have been differentially retained in various classes. Accordingly, we find Pgc2 in sauropsids, amphibians and marsupials, but not in eutherian mammals. Pgbc was retained in amphibians, but duplicated in the ancestor of amniotes giving rise to Pgb and Pgc1. The latter was retained in mammals and probably in reptiles and marsupials but not in birds. Pgb was kept in all of the amniote clade with independent episodes of loss in some mammalian species. Lineage specific expansions of Pgc2 and Pgbc have also occurred in marsupials and amphibians respectively. We find that teleost and tetrapod Pgc genes reside in distinct genomic regions hinting at a possible translocation. CONCLUSIONS: We conclude that the repertoire of Pgc genes is larger than previously reported, and that tandem duplications have modelled the history of Pgc genes. We hypothesize that gene expansion lead to functional divergence in tetrapods, coincident with the

  11. Gene doping.

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    Haisma, H J; de Hon, O

    2006-04-01

    Together with the rapidly increasing knowledge on genetic therapies as a promising new branch of regular medicine, the issue has arisen whether these techniques might be abused in the field of sports. Previous experiences have shown that drugs that are still in the experimental phases of research may find their way into the athletic world. Both the World Anti-Doping Agency (WADA) and the International Olympic Committee (IOC) have expressed concerns about this possibility. As a result, the method of gene doping has been included in the list of prohibited classes of substances and prohibited methods. This review addresses the possible ways in which knowledge gained in the field of genetic therapies may be misused in elite sports. Many genes are readily available which may potentially have an effect on athletic performance. The sporting world will eventually be faced with the phenomena of gene doping to improve athletic performance. A combination of developing detection methods based on gene arrays or proteomics and a clear education program on the associated risks seems to be the most promising preventive method to counteract the possible application of gene doping.

  12. A new rauisuchid (Archosauria, Pseudosuchia from the Upper Triassic (Norian of New Mexico increases the diversity and temporal range of the clade

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    Emily J. Lessner

    2016-09-01

    Full Text Available Rauisuchids are large (2–6 m in length, carnivorous, and quadrupedal pseudosuchian archosaurs closely related to crocodylomorphs. Though geographically widespread, fossils of this clade are relatively rare in Late Triassic assemblages. The middle Norian (∼212 Ma Hayden Quarry of northern New Mexico, USA, in the Petrified Forest Member of the Chinle Formation, has yielded isolated postcranial elements and associated skull elements of a new species of rauisuchid. Vivaron haydeni gen. et. sp. nov. is diagnosed by the presence of two posteriorly directed prongs at the posterior end of the maxilla for articulation with the jugal. The holotype maxilla and referred elements are similar to those of the rauisuchid Postosuchus kirkpatricki from the southwestern United States, but V. haydeni shares several maxillary apomorphies (e.g., a distinct dropoff to the antorbital fossa that is not a ridge, a straight ventral margin, and a well defined dental groove with the rauisuchid Teratosaurus suevicus from the Norian of Germany. Despite their geographic separation, this morphological evidence implies a close phylogenetic relationship between V. haydeni and T. suevicus. The morphology preserved in the new Hayden Quarry rauisuchid V. haydeni supports previously proposed and new synapomorphies for nodes within Rauisuchidae. The discovery of Vivaron haydeni reveals an increased range of morphological disparity for rauisuchids from the low-paleolatitude Chinle Formation and a clear biogeographic connection with high paleolatitude Pangea.

  13. Establishment of the cross-clade antigen detection system for H5 subtype influenza viruses using peptide monoclonal antibodies specific for influenza virus H5 hemagglutinin.

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    Takahashi, Hitoshi; Nagata, Shiho; Odagiri, Takato; Kageyama, Tsutomu

    2018-04-15

    The H5 subtype of highly pathogenic avian influenza (H5 HPAI) viruses is a threat to both animal and human public health and has the potential to cause a serious future pandemic in humans. Thus, specific and rapid detection of H5 HPAI viruses is required for infection control in humans. To develop a simple and rapid diagnostic system to detect H5 HPAI viruses with high specificity and sensitivity, we attempted to prepare monoclonal antibodies (mAbs) that specifically recognize linear epitopes in hemagglutinin (HA) of H5 subtype viruses. Nine mAb clones were obtained from mice immunized with a synthetic partial peptide of H5 HA molecules conserved among various H5 HPAI viruses. The antigen-capture enzyme-linked immunosorbent assay using the most suitable combination of these mAbs, which bound specifically to lysed H5 HA under an optimized detergent condition, was specific for H5 viruses and could broadly detect H5 viruses in multiple different clades. Taken together, these peptide mAbs, which recognize linear epitopes in a highly conserved region of H5 HA, may be useful for specific and highly sensitive detection of H5 HPAI viruses and can help in the rapid diagnosis of human, avian, and animal H5 virus infections. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Strong support for Rensch's rule in an American clade of lizards (Teiidae and Gymnophtalmidae) and a paradox of the largest tejus

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    Frýdlová, Petra; Frynta, Daniel

    2015-06-01

    Rensch's rule predicts an allometric relationship between male and female body size stating that the sexual size dimorphism (SSD) increases with body size in male-larger taxa and decreases in female-larger taxa in groups of related species. It means that the relationship between the male and female body size is hyperallometric, i.e., the allometric exponent of this relationship exceeds the unity. We explored the relationship between the male and female body size in a New World clade of lizards consisting of sister families Teiidae and Gymnophthalmidae, which exhibit a great variation in both their adult body sizes and SSD. All our estimates of the reduced major axis regression slopes ranged from 1.067 to 1.229 and clearly followed a pattern consistent with the Rensch's rule. Despite a clear general trend, giant species from the subfamily Tupinambinae show paradoxically only poor SSD. The cases of extreme male-larger SSD were found in species of moderate body size belonging to the genera Ameiva and Cnemidophorus. The abovementioned deviations from the hyperallometric relationship between the male and female body size are surprising and require further examination.

  15. Scheffersomyces cryptocercus: a new xylose-fermenting yeast associated with the gut of wood roaches and new combinations in the Sugiyamaella yeast clade.

    Science.gov (United States)

    Urbina, Hector; Frank, Robert; Blackwell, Meredith

    2013-01-01

    The gut of wood-feeding insects is a microhabitat for a specialized community of microbes, including bacteria and several groups of eukaryotes such as nematodes, parabasalids and fungi. The characterization of gut yeast communities from a variety of insects has shown that certain yeasts often are associated with the insects. The gut of wood-feeding insects is rich in ascomycete yeasts and in particular xylose-fermenting (X-F) and assimilating yeasts have been consistently present in the gut of lignicolous insects. The objective of this study was the characterization of the yeast flora from the gut of the wood roach Cryptocercus sp. (Blattodea: Cryptocercidae). Five wood roaches were collected along the Appalachian Trail near the border between Tennessee and North Carolina, USA. We isolated 18 yeast strains from the wood roaches identified as Sugiyamaella paludigena and Sugiyamaella lignohabitans, xylose-assimilating yeasts, and Scheffersomyces cryptocercus (NRRL Y-48824(T) = CBS 12658) a new species of X-F yeast. The presence of X-F and certain non X-F yeasts in the gut of the subsocial wood roach Cryptocercus sp. extends the previous findings of associations between certain ascomycete yeasts and lignicolous insects. New combinations were made for 13 asexual members of the Sugiyamaella clade.

  16. Evolution of Neutralization Response in HIV-1 Subtype C-Infected Individuals Exhibiting Broad Cross-Clade Neutralization of HIV-1 Strains

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    Narayanaiah Cheedarla

    2018-03-01

    Full Text Available Strain-specific neutralizing antibodies develop in all human immunodeficiency virus type 1 (HIV-1-infected individuals. However, only 10–30% of infected individuals produce broadly neutralizing antibodies (bNAbs. Identification and characterization of these bNAbs and understanding their evolution dynamics are critical for obtaining useful clues for the development of an effective HIV vaccine. Very recently, we published a study in which we identified 12 HIV-1 subtype C-infected individuals from India whose plasma showed potent and broad cross-clade neutralization (BCN ability (1. In the present study, we report our findings on the evolution of host bNAb response over a period of 4 years in a subset of these individuals. Three of the five individuals (NAB033, NAB059, and NAB065 demonstrated a significant increase (p < 0.05 in potency. Interestingly, two of the three samples also showed a significant increase in CD4 binding site-specific antibody response, maintained stable CD4+ T cell counts (>350 cells/mm3 and continued to remain ART-naïve for more than 10 years after initial diagnosis, implying a strong clinical correlation with the development and evolution of broadly neutralizing antibody response against HIV-1.

  17. Evaluation of the zoonotic potential of multiple subgroups of clade 2.3.4.4 influenza A (H5N8) virus.

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    Lee, Yu-Na; Lee, Eun-Kyoung; Song, Byung-Min; Heo, Gyeong-Beom; Woo, Sang-Hee; Cheon, Sun-Ha; Lee, Youn-Jeong

    2018-03-01

    Clade 2.3.4.4 H5N8 highly pathogenic avian influenza viruses (HPAIVs) have spread worldwide. Phylogenetic analysis identified two genetic groups of the H5N8 HPAIVs in South Korea; group A evolved further into four subgroups. Here, we examined the zoonotic potential, both in vivo and in vitro, of genetically distinct subgroups of H5N8 HPAIVs isolated in South Korea. When compared with other subgroups, A/mallard/Korea/H2102/2015 (H2102) virus caused relatively severe disease in mice at high doses. In ferrets, all H5N8 viruses replicated restrictively in the respiratory tract and did not induce significant clinical signs of influenza infection. In vitro studies, all viruses displayed a hemagglutinin phenotype that was poorly adapted for infection of mammals, although the H2102 virus exhibited higher replication kinetics at 33°C than the others. Although H5N8 HPAIVs have not yet acquired all the characteristics required for adaptation to mammals, their ability to evolve continuously underscores the need for timely risk assessment. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Elusive Origins of the Extra Genes in Aspergillus oryzae

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    Khaldi, Nora; Wolfe, Kenneth H.

    2008-01-01

    The genome sequence of Aspergillus oryzae revealed unexpectedly that this species has approximately 20% more genes than its congeneric species A. nidulans and A. fumigatus. Where did these extra genes come from? Here, we evaluate several possible causes of the elevated gene number. Many gene families are expanded in A. oryzae relative to A. nidulans and A. fumigatus, but we find no evidence of ancient whole-genome duplication or other segmental duplications, either in A. oryzae or in the common ancestor of the genus Aspergillus. We show that the presence of divergent pairs of paralogs is a feature peculiar to A. oryzae and is not shared with A. nidulans or A. fumigatus. In phylogenetic trees that include paralog pairs from A. oryzae, we frequently find that one of the genes in a pair from A. oryzae has the expected orthologous relationship with A. nidulans, A. fumigatus and other species in the subphylum Eurotiomycetes, whereas the other A. oryzae gene falls outside this clade but still within the Ascomycota. We identified 456 such gene pairs in A. oryzae. Further phylogenetic analysis did not however indicate a single consistent evolutionary origin for the divergent members of these pairs. Approximately one-third of them showed phylogenies that are suggestive of horizontal gene transfer (HGT) from Sordariomycete species, and these genes are closer together in the A. oryzae genome than expected by chance, but no unique Sordariomycete donor species was identifiable. The postulated HGTs from Sordariomycetes still leave the majority of extra A. oryzae genes unaccounted for. One possible explanation for our observations is that A. oryzae might have been the recipient of many separate HGT events from diverse donors. PMID:18725939

  19. Elusive origins of the extra genes in Aspergillus oryzae.

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    Nora Khaldi

    Full Text Available The genome sequence of Aspergillus oryzae revealed unexpectedly that this species has approximately 20% more genes than its congeneric species A. nidulans and A. fumigatus. Where did these extra genes come from? Here, we evaluate several possible causes of the elevated gene number. Many gene families are expanded in A. oryzae relative to A. nidulans and A. fumigatus, but we find no evidence of ancient whole-genome duplication or other segmental d