Evolution of Nematode Sex Determination

性别决定机制因门而异，尽管有证据表明它们具有深层同源性。这个项目使用线虫属隐杆线虫来研究性别决定在短时间尺度上是如何进化的。它提供了一个特征良好的参考物种（秀丽隐杆线虫），性模式的差异（雄雄性与雌雄同体），以及第一对密切相关的动物基因组序列。该项目将开发C. briggsae作为一个真正的遗传系统，这将使与秀丽隐杆线虫精确比较。使用了两种互补的方法来鉴定C. briggsae性别决定突变：基于表型的经典正向遗传筛选和通过基于pcr的方法进行缺失突变的反向遗传筛选。这些方法将有助于阐明交配系统是如何进化的，以及两个趋同雌雄同体物种的生殖系发育细节是相同还是不同。此外，该项目将有助于将C. briggsae发展为一个成熟的发育遗传系统。本科生和研究生的参与是该项目的核心，确保青年科学家的培训和指导是一个主要组成部分。

ABSTRACTSex determination mechanisms vary wildly from phylum to phylum, even as evidence for their deep homology accumulates. This project uses the nematode genus Caenorhabditis to study how sex determination evolves over short time scales. It offers a well-characterized reference species (C. elegans), variation in sexual mode (androdioecy vs. gonochorism), and the first pair of closely related animal genome sequences. The project will develop C. briggsae as a true genetic system, which will enable precise comparisons with C. elegans. Two complementary approaches for identifying C. briggsae sex determination mutations are used: classical forward genetic screens based on phenotype and reverse genetic screens for deletion mutations via a PCR-based method. Together these approaches will help clarify how mating systems evolve, and whether the details of germline development are the same or different in two convergent hermaphroditic species. In addition, the project will contribute to the development of C. briggsae as a mature developmental genetic system. Undergraduate and graduate student participation is central to the project, ensuring that the training and mentoring of young scientists is a major component.