Genetics of Mitochondrial Inheritance in C. elegans

线虫线粒体遗传的遗传学

• 批准号: 6786958
• 负责人: CRAIG W LAMUNYON
• 金额: $ 5.02万
• 依托单位: CALIFORNIA STATE POLY U POMONA
• 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 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6786958
• 关键词: Caenorhabditis elegans; cell death; developmental genetics; extrachromosomal DNA; gene expression; gene mutation; genetic mapping; genetic markers; immunocytochemistry; mitochondria; phenotype; polymerase chain reaction; protein degradation; spermatogenesis; tissue /cell culture; ubiquitin; western blottings

DESCRIPTION (provided by applicant): Mitochondria are inherited only from the egg, not from the sperm. The research proposed here investigates the mechanism of this inheritance. Mitochondria are semiautonomous organelles that contain their own genome and that are involved in oxidative respiration, a process that generates damaging oxygen radicals. In addition to processing energy, mitochondria can stimulate apoptosis. Mitochondrial genetic defects have been identified in a number of human diseases. Several studies suggest that inheritance of paternal mitochondria may be harmful or even fatal to the developing embryo. Recent evidence from mammals has begun to unravel the mechanism of maternal mitochondrial inheritance. It appears that during spermatogenesis, the sperm mitochondria are marked with ubiquitin, a small protein that targets molecules for degradation. Here, I propose to use a genetic approach to investigate the mechanism of paternal mitochondrial destruction in the nematode C. elegans. The study will make use of the powerful genetic and genomic tools that have been developed for this species. Specifically, we will investigate the hypothesis that paternal mitochondria are tagged during spermatogenesis for destruction inside the developing embryo. We will first randomly mutagenize worms and select for mutations that block the destruction of sperm mitochondria. We have preliminary evidence that we can obtain such mutations. The mutated genes will be mapped and their sequence determined by comparison with linked sperm specific genes; essentially all sperm specific genes in the genome are now known as a result of DNA microarray analyses. Second, in a collaborative project, we will knock out ubiquitin-associated genes that are known to be sperm specific. If these mutations block sperm degradation of sperm mitochondria, then ubiquitin is involved in the destruction of sperm mitochondria in C. elegans. Finally, in another collaborative project, we will examine sperm for the presence of ubiquitin by (i) Western analysis, and (ii) by immunocytochemistry. The results of these experiments will likely identify genes involved in the degradation of sperm mitochondria. Because all the genes in the C. elegans genome are known, and most have predicted functions, identification of genes involved in mitochondrial inheritance will help elucidate the mechanism of this inheritance. Also, studying the phenotypes of offspring with paternal mitochondria will identify potential health impacts of inheriting paternal mitochondria.

描述（由申请人提供）：线粒体仅遗传自 卵子不是精子本文的研究旨在探讨 这份遗产。线粒体是半自主的细胞器， 它们自己的基因组，并参与氧化呼吸，这一过程， 会产生有害的氧自由基除了处理能量之外， 线粒体可刺激细胞凋亡。线粒体遗传缺陷一直是 在许多人类疾病中发现。一些研究表明 父亲线粒体的遗传可能对他们有害甚至致命。 胚胎发育最近来自哺乳动物的证据已经开始解开 母系线粒体遗传机制。看来，在 精子发生时，精子线粒体标记有泛素， 以分子为目标进行降解的蛋白质。在这里，我建议使用一个 遗传学方法来研究父系线粒体的机制 线虫C.优雅的这项研究将利用强大的 为这个物种开发的基因和基因组工具。 具体地说，我们将调查的假设，父亲的线粒体是 在精子发生过程中被标记以破坏发育中的胚胎。我们 将首先随机诱变蠕虫，并选择突变，阻止 破坏精子线粒体。我们有初步证据证明 获得这样的突变。突变的基因将被绘制出来， 通过与相连的精子特异性基因比较确定;基本上所有 基因组中的精子特异性基因是DNA微阵列的结果 分析。第二，在合作项目中，我们将淘汰 泛素相关基因，已知是精子特异性的。如果这些 突变阻止精子线粒体的精子降解，那么泛素是 在C.优雅的最后在 另一个合作项目，我们将检查精子的存在， 通过（i）Western分析，和（ii）免疫细胞化学。结果 这些实验将可能确定参与降解的基因， 精子线粒体因为C.线虫基因组是已知的， 大多数都有预测的功能，识别参与的基因 线粒体遗传将有助于阐明这一机制， 传承此外，研究与父亲的后代的表型 线粒体将识别遗传父系遗传的潜在健康影响 线粒体