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Gary M. Wessel - One of the best experts on this subject based on the ideXlab platform.

  • Selective accumulation of Germ-Line associated gene products in early Development of the sea star and distinct differences from Germ-Line Development in the sea urchin
    Developmental dynamics : an official publication of the American Association of Anatomists, 2013
    Co-Authors: Tara Fresques, Adrian Reich, Vanesa Zazueta-novoa, Gary M. Wessel
    Abstract:

    Background: Echinodermata is a diverse phylum, a sister group to chordates, and contains diverse organisms that may be useful to understand varied mechanisms of Germ-Line specification. Results: We tested 23 genes in Development of the sea star Patiria miniata that fall into five categories: (1) Conserved Germ-Line factors; (2) Genes involved in the inductive mechanism of Germ-Line specification; (3) Germ-Line associated genes; (4) Molecules involved in left–right asymmetry; and (5) Genes involved in regulation and maintenance of the genome during early embryogenesis. Overall, our results support the contention that the posterior enterocoel is a source of the Germ Line in the sea star P. miniata. Conclusions: The Germ Line in this organism appears to be specified late in embryogenesis, and in a pattern more consistent with inductive interactions amongst cells. This is distinct from the mechanism seen in sea urchins, a close relative of the sea star clad. We propose that P. miniata may serve as a valuable model to study inductive mechanisms of Germ-cell specification and when compared with Germ-Line formation in the sea urchin S. purpuratus may reveal Developmental transitions that occur in the evolution of inherited and inductive mechanisms of Germ-Line specification. Developmental Dynamics 243:568–587, 2014. © 2013 Wiley Periodicals, Inc.

  • Autonomy in specification of primordial Germ cells and their passive translocation in the sea urchin.
    Development, 2012
    Co-Authors: Mamiko Yajima, Gary M. Wessel
    Abstract:

    The process of Germ Line determination involves many conserved genes, yet is highly variable. Echinoderms are positioned at the base of Deuterostomia and are crucial to understanding these evolutionary transitions, yet the mechanism of Germ Line specification is not known in any member of the phyla. Here we demonstrate that small micromeres (SMics), which are formed at the fifth cell division of the sea urchin embryo, illustrate many typical features of primordial Germ cell (PGC) specification. SMics autonomously express Germ Line genes in isolated culture, including selective Vasa protein accumulation and transcriptional activation of nanos; their descendants are passively displaced towards the animal pole by secondary mesenchyme cells and the elongating archenteron during gastrulation; Cadherin (G form) has an important role in their Development and clustering phenotype; and a left/right integration into the future adult anlagen appears to be controlled by a late Developmental mechanism. These results suggest that sea urchin SMics share many more characteristics typical of PGCs than previously thought, and imply a more widely conserved system of Germ Line Development among metazoans.

  • Post-translational regulation by gustavus contributes to selective Vasa protein accumulation in multipotent cells during embryogenesis
    Developmental biology, 2010
    Co-Authors: Eric A. Gustafson, Mamiko Yajima, Celina E. Juliano, Gary M. Wessel
    Abstract:

    Vasa is a broadly conserved DEAD-box RNA helicase associated with Germ Line Development and is expressed in multipotent cells in many animals. During embryonic Development of the sea urchin Strongylocentrotus purpuratus, Vasa protein is enriched in the small micromeres despite a uniform distribution of vasa transcript. Here we show that the Vasa coding region is sufficient for its selective enrichment and find that gustavus, the B30.2/SPRY and SOCS box domain gene, contributes to this phenomenon. In vitro binding analyses show that Gustavus binds the N-terminal and DEAD-box portions of Vasa protein independently. A knockdown of Gustavus protein reduces both Vasa protein abundance and its propensity for accumulation in the small micromeres, whereas overexpression of the Vasa-interacting domain of Gustavus (GusΔSOCS) results in Vasa protein accumulation throughout the embryo. We propose that Gustavus has a conserved, positive regulatory role in Vasa protein accumulation during embryonic Development.

Andreas Wodarz - One of the best experts on this subject based on the ideXlab platform.

  • Windei, the Drosophila Homolog of mAM/MCAF1, Is an Essential Cofactor of the H3K9 Methyl Transferase dSETDB1/Eggless in Germ Line Development
    PLoS genetics, 2009
    Co-Authors: Carmen M. Koch, Mona Honemann-capito, Diane Egger-adam, Andreas Wodarz
    Abstract:

    The epigenetic regulation of gene expression by the covalent modification of histones is a fundamental mechanism required for the proper differentiation of Germ Line cells during Development. Trimethylation of histone 3 lysine 9 (H3K9me3) leads to chromatin silencing and the formation of heterochromatin by recruitment of heterochromatin protein 1 (HP1). dSETDB1/Eggless (Egg), the ortholog of the human methyltransferase SETDB1, is the only essential H3K9 methyltransferase in Drosophila and is required for H3K9 trimethylation in the female Germ Line. Here we show that Windei (Wde), the Drosophila homolog of mouse mAM and human MCAF1, is an essential cofactor of Egg required for its nuclear localization and function in female Germ Line cells. By deletion analysis combined with coimmunoprecipitation, we have identified the protein regions in Wde and Egg that are necessary and sufficient for the interaction between the two proteins. We furthermore identified a region of Egg that gets covalently modified by SUMOylation, which may facilitate the formation of higher order chromatin-modifying complexes. Together with Egg, Wde localizes to euchromatin, is enriched on chromosome 4, and binds to the Painting of fourth (POF) protein. Our data provide the first genetic and phenotypic analysis of a mAM/MCAF1 homolog in a model organism and demonstrate its essential function in the survival of Germ Line cells.

  • windei the drosophila homolog of mam mcaf1 is an essential cofactor of the h3k9 methyl transferase dsetdb1 eggless in Germ Line Development
    PLOS Genetics, 2009
    Co-Authors: Carmen M. Koch, Mona Honemanncapito, Diane Eggeradam, Andreas Wodarz
    Abstract:

    The epigenetic regulation of gene expression by the covalent modification of histones is a fundamental mechanism required for the proper differentiation of Germ Line cells during Development. Trimethylation of histone 3 lysine 9 (H3K9me3) leads to chromatin silencing and the formation of heterochromatin by recruitment of heterochromatin protein 1 (HP1). dSETDB1/Eggless (Egg), the ortholog of the human methyltransferase SETDB1, is the only essential H3K9 methyltransferase in Drosophila and is required for H3K9 trimethylation in the female Germ Line. Here we show that Windei (Wde), the Drosophila homolog of mouse mAM and human MCAF1, is an essential cofactor of Egg required for its nuclear localization and function in female Germ Line cells. By deletion analysis combined with coimmunoprecipitation, we have identified the protein regions in Wde and Egg that are necessary and sufficient for the interaction between the two proteins. We furthermore identified a region of Egg that gets covalently modified by SUMOylation, which may facilitate the formation of higher order chromatin-modifying complexes. Together with Egg, Wde localizes to euchromatin, is enriched on chromosome 4, and binds to the Painting of fourth (POF) protein. Our data provide the first genetic and phenotypic analysis of a mAM/MCAF1 homolog in a model organism and demonstrate its essential function in the survival of Germ Line cells.

C. Wiederkehr - One of the best experts on this subject based on the ideXlab platform.

  • Database model and specification of GermOnLine Release 2.0, a cross-species community annotation knowledgebase on Germ cell differentiation
    Bioinformatics (Oxford England), 2004
    Co-Authors: C. Wiederkehr, R. Basavaraj, C. Sarrauste De Menthière, Leandro C. Hermida, R. Koch, Ulrich Schlecht, Benjamin Masdoua, R. Ishii, V. Cassen, Masayuki Yamamoto
    Abstract:

    Summary: GermOnLine is a web-accessible relational database that enables life scientists to make a significant and sustained contribution to the annotation of genes relevant for the fields of mitosis, meiosis, Germ Line Development and gametogenesis across species. This novel approach to genome annotation includes a platform for knowledge submission and curation as well as microarray data storage and visualization hosted by a global network of servers. Availability: The database is accessible at http://www.GermonLine.org/. For convenient world-wide access we have set up a network of servers in Europe (http://GermonLine.unibas.ch/; http://GermonLine.igh.cnrs.fr/), Japan (http://GermonLine.biochem.s.u-tokyo.ac.jp/) and USA (http://GermonLine.yeastgenome.org/). Supplementary information: Extended documentation of the database is available through the link 'About GermOnLine' at the websites.

  • GermOnLine, a cross-species community knowledgebase on Germ cell differentiation.
    Nucleic Acids Research, 2004
    Co-Authors: C. Wiederkehr, R. Basavaraj, C. Sarrauste De Menthière, Leandro C. Hermida, R. Koch, Ulrich Schlecht, Angelika Amon, Sophie Brachat, Michael Breitenbach, Peter Briza
    Abstract:

    GermOnLine provides information and microarray expression data for genes involved in mitosis and meiosis, gamete formation and Germ Line Development across species. The database has been developed, and is being curated and updated, by life scientists in cooperation with bioinformaticists. Information is contributed through an onLine form using free text, images and the controlled vocabulary developed by the GeneOntology Consortium. Authors provide up to three references in support of their contribution. The database is governed by an international board of scientists to ensure a standardized data format and the highest quality of GermOnLine's information content. Release 2.0 provides exclusive access to microarray expression data from Saccharomyces cerevisiae and Rattus norvegicus, as well as curated information on approximately 700 genes from various organisms. The locus report pages include links to external databases that contain relevant annotation, microarray expression and proteome data. Conversely, the Saccharomyces Genome Database (SGD), S.cerevisiae GeneDB and Swiss-Prot link to the budding yeast section of GermOnLine from their respective locus pages. GermOnLine, a fully operational prototype subject-oriented knowledgebase designed for community annotation and array data visualization, is accessible at http://www.GermonLine.org. The target audience includes researchers who work on mitotic cell division, meiosis, gametogenesis, Germ Line Development, human reproductive health and comparative genomics.

  • GermOnLine, a new cross-species community annotation database on Germ-Line Development and gametogenesis
    Nature genetics, 2003
    Co-Authors: Michael Primig, C. Wiederkehr, R. Basavaraj, C. Sarrauste De Menthière, Leandro C. Hermida, R. Koch, Ulrich Schlecht, Hugh G. Dickinson, Marc Fellous, J. A. Grootegoed
    Abstract:

    GermOnLine, a new cross-species community annotation database on Germ-Line Development and gametogenesis

J. A. Grootegoed - One of the best experts on this subject based on the ideXlab platform.

Ulrich Schlecht - One of the best experts on this subject based on the ideXlab platform.

  • Database model and specification of GermOnLine Release 2.0, a cross-species community annotation knowledgebase on Germ cell differentiation
    Bioinformatics (Oxford England), 2004
    Co-Authors: C. Wiederkehr, R. Basavaraj, C. Sarrauste De Menthière, Leandro C. Hermida, R. Koch, Ulrich Schlecht, Benjamin Masdoua, R. Ishii, V. Cassen, Masayuki Yamamoto
    Abstract:

    Summary: GermOnLine is a web-accessible relational database that enables life scientists to make a significant and sustained contribution to the annotation of genes relevant for the fields of mitosis, meiosis, Germ Line Development and gametogenesis across species. This novel approach to genome annotation includes a platform for knowledge submission and curation as well as microarray data storage and visualization hosted by a global network of servers. Availability: The database is accessible at http://www.GermonLine.org/. For convenient world-wide access we have set up a network of servers in Europe (http://GermonLine.unibas.ch/; http://GermonLine.igh.cnrs.fr/), Japan (http://GermonLine.biochem.s.u-tokyo.ac.jp/) and USA (http://GermonLine.yeastgenome.org/). Supplementary information: Extended documentation of the database is available through the link 'About GermOnLine' at the websites.

  • GermOnLine, a cross-species community knowledgebase on Germ cell differentiation.
    Nucleic Acids Research, 2004
    Co-Authors: C. Wiederkehr, R. Basavaraj, C. Sarrauste De Menthière, Leandro C. Hermida, R. Koch, Ulrich Schlecht, Angelika Amon, Sophie Brachat, Michael Breitenbach, Peter Briza
    Abstract:

    GermOnLine provides information and microarray expression data for genes involved in mitosis and meiosis, gamete formation and Germ Line Development across species. The database has been developed, and is being curated and updated, by life scientists in cooperation with bioinformaticists. Information is contributed through an onLine form using free text, images and the controlled vocabulary developed by the GeneOntology Consortium. Authors provide up to three references in support of their contribution. The database is governed by an international board of scientists to ensure a standardized data format and the highest quality of GermOnLine's information content. Release 2.0 provides exclusive access to microarray expression data from Saccharomyces cerevisiae and Rattus norvegicus, as well as curated information on approximately 700 genes from various organisms. The locus report pages include links to external databases that contain relevant annotation, microarray expression and proteome data. Conversely, the Saccharomyces Genome Database (SGD), S.cerevisiae GeneDB and Swiss-Prot link to the budding yeast section of GermOnLine from their respective locus pages. GermOnLine, a fully operational prototype subject-oriented knowledgebase designed for community annotation and array data visualization, is accessible at http://www.GermonLine.org. The target audience includes researchers who work on mitotic cell division, meiosis, gametogenesis, Germ Line Development, human reproductive health and comparative genomics.

  • GermOnLine, a new cross-species community annotation database on Germ-Line Development and gametogenesis
    Nature genetics, 2003
    Co-Authors: Michael Primig, C. Wiederkehr, R. Basavaraj, C. Sarrauste De Menthière, Leandro C. Hermida, R. Koch, Ulrich Schlecht, Hugh G. Dickinson, Marc Fellous, J. A. Grootegoed
    Abstract:

    GermOnLine, a new cross-species community annotation database on Germ-Line Development and gametogenesis