FUNCTIONS OF A CONSERVED GERMLINE HELICASE IN C.ELEGANS

线虫中保守种系解旋酶的功能

• 批准号: 6472925
• 负责人: T Keith Blackwell
• 金额: $ 27.81万
• 依托单位: IMMUNE DISEASE INSTITUTE, INC.
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-01 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6472925
• 关键词: Caenorhabditis elegans; apoptosis; binding proteins; cell proliferation; cytoplasm; egg /ovum; gametogenesis; gene deletion mutation; gene expression; genetic regulation; genetically modified animals; germ cells; helicase; in situ hybridization; messenger RNA; polymerase chain reaction; protein localization; protein protein interaction; protein structure function; terminal nick end labeling; transmission electron microscopy; yeast two hybrid system

DESCRIPTION (provided by applicant): Eukaryotes each appear to encode a single ortholog of CGH- 1 (conserved germline helicase), a DEAD box RNA helicase that is germline-specific in many organisms and required for gametogenesis in yeast. We have shown that C. elegans CGH-1 is specific to the germline and early embryo, and is associated with germline P granules and other putative mRNA-protein particles. cgh-1 is required to form functional gametes, and without it essentially all oocytes die by apoptosis through a germline-specific pathway. This mechanism normally kills up to half of all developing oocytes, apparently so that their cytoplasm is provided to their surviving sisters. Our findings suggest that physiological germline apoptosis, a conserved aspect of gametogenesis, can act as a surveillance mechanism that monitors aspects of germline cytoplasm formation. We hypothesize that CGH- 1 regulates metabolism or translation of particular mRNAs that are stored during gametogenesis, and that elucidation of these functions will yield novel and broadly applicable insights into germline development and apoptosis. We will test these models by elucidating critical aspects of how CGH-l contributes to gametogenesis, and functions at the molecular level. In the latter experiments, we will elucidate the basis for its complex expression pattern, determine whether it interacts functionally with RNA-associated complexes that bind its orthologs in other species, test whether it associates with maternal mRNAs, and use unbiased methods to identify other CGH-1-binding proteins that may be species-specific. These experiments will provide insights into how apoptosis is triggered in developing C. elegans oocytes that may be broadly applicable to understanding why physiological germline cell death occurs. At the same time, they will elucidate post-transcriptional gene regulation mechanisms that may be of conserved importance during gametogenesis, and possibly for proliferation or survival of other stem cell types.

描述（由申请人提供）：真核生物每个似乎都编码一个 CGH-1的直系同源物（保守种系解旋酶），一种死盒RNA解旋酶， 在许多生物体中是生殖特异性的，并且需要酵母的配子发生。 我们已经证明秀丽隐杆线虫CGH-1是特定于种系和早期的 胚胎，与种系P颗粒和其他假定相关 mRNA-蛋白质颗粒。需要CGH-1形成功能配子，并且 本质上没有它所有卵母细胞因细菌特异性而死亡 路径。这种机制通常会杀死所有发育中的卵母细胞的一半， 显然，以便将其细胞质提供给他们幸存的姐妹。我们的 调查结果表明，生理种系凋亡，一个保守的方面 配子发生，可以充当监视的监视机制 种系细胞质形成。我们假设CGH-1调节新陈代谢 或在配子发生过程中存储的特定mRNA的翻译，以及 这些功能的阐明将产生新颖且广泛适用 对种系发育和凋亡的见解。我们将通过 阐明CGH-L如何促进配子发生的关键方面， 分子水平的功能。在后一个实验中，我们将阐明 其复杂表达模式的基础，确定它是否相互作用 与RNA相关的复合物在功能上结合其直系同源物 物种，测试它是否与母体mRNA相关，并使用公正 识别可能是物种特异性的其他CGH-1结合蛋白的方法。 这些实验将提供有关如何触发凋亡的见解 开发秀丽隐杆线虫卵母细胞可能广泛适用于理解 为什么会发生生理种系细胞死亡。同时，他们将 阐明可能是的转录后基因调节机制 在配子发生过程中的重要性，可能是增殖或 其他干细胞类型的生存。