FUNCTIONS OF A CONSERVED GERMLINE HELICASE IN C.ELEGANS

描述(由申请人提供)：真核生物似乎每个都编码一个 CGH-1(保守的生殖系解旋酶)的同源基因，一个死盒RNA解旋酶 在许多生物体中是种系特有的，是酵母配子发生所必需的。 我们已经证明线虫CGH-1是胚系和早期特异的 胚胎，并与生殖系P颗粒和其他推测的 信使核糖核酸-蛋白质颗粒。CGH-1是形成功能配子所必需的， 如果没有它，基本上所有的卵母细胞都会通过生殖系特异性的 路径。这种机制通常会杀死多达一半的发育中的卵母细胞， 显然是为了把他们的细胞质提供给他们幸存的姐妹。我们的 研究结果表明，生理性生殖细胞凋亡，一个保守的方面 配子发生，可以作为一种监视机制，监视 胚系细胞质的形成。我们假设CGH-1调节代谢 或翻译在配子发生期间存储的特定mRNA，以及 对这些功能的阐明将产生新的和广泛适用的结果 对生殖系发育和细胞凋亡的洞察。我们将通过以下方式测试这些模型 阐明CGH-L如何促进配子发生的关键方面，以及 在分子水平上发挥作用。在后面的实验中，我们将阐明 其复杂表达模式的基础，决定了它是否相互作用 在功能上与RNA相关的复合体结合其直系物在其他 物种，测试它是否与母体mRNAs相关，并使用公正的 鉴定其他可能具有物种特异性的CGH-1结合蛋白的方法。 这些实验将提供对细胞凋亡是如何被触发的洞察 发育线虫卵母细胞可能广泛适用于理解 为什么会发生生理性生殖细胞死亡。与此同时，他们将 阐明转录后基因调控机制可能是 在配子发生过程中具有保守的重要性，可能对繁殖或 其他类型干细胞的存活。

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.