Genomic analysis of mating and sexual conflict in Caenorhabditis

描述（由申请人提供）：通过有性生殖进行的遗传交换的不同模式对种群内部和种群之间的遗传变异和进化分化具有深远的影响。当交换频率可以在几个数量级上变化时，这一点尤其正确。以雌雄同株的模式线虫秀丽隐杆线虫及其雌雄异株的近亲雷马尼线虫为研究对象，提出了平行的研究项目，以鉴定或分类这些生物之间的差异繁殖和性别之间的差异适合度的基因。本研究的目的是：1。绘制导致不同品系间雄性频率差异的基因图谱并评估其功能。初步数据表明，在线虫中维持的雄性的频率在不同的菌株之间可能相差多达3000倍。使用240个重组自交系（RIL），这些自交系的单核苷酸多态性位点已被基因分型，将使用高通量方法识别和功能评估与雄性交配能力差异相关的基因组区域，包括基因表达分析，使用干扰RNA （RNAi）敲低和转化拯救。2. 确定C. remanei中潜在的性冲突和精子竞争的基因的性质，C. remanei是一种严格的异交物种，正在成为进化生态学研究的模式生物。初步结果表明，该物种存在精子竞争和性冲突。根据雌性和雄性的遗传背景，雄性交配会以一种特定的方式减少雌性寿命，最多可减少33%。雄性对雌性寿命和精子竞争能力影响的不同株系之间的杂交将用于鉴定这些雄性交配能力相关性状的遗传基础。

DESCRIPTION (provided by applicant): Differential patterns of genetic exchange via sexual reproduction can have a profound impact on genetic variation and evolutionary divergence within and between populations. This is especially true when the frequency of exchange can vary over several orders of magnitude. Using the androdioecious model nematode, C. elegans, and its dioeceous relative, C. remanei, parallel research projects are proposed to identify or classify the genes underlying differential reproduction among strains and differential fitness between sexes of these organisms. The objectives of this research are to: 1. Map the genes contributing to among strain differences in male frequency and evaluate their function. Preliminary data demonstrates that the frequency of males maintained in C. elegans can differ between strains by as much as factor of 3,000. Using 240 recombinant inbred lines (RIL) that have been genotyped at >1200 single nucleotide polymorphic loci, genomic regions associated with this difference in male mating ability will be identified and functionally assessed using high throughput approaches including the analysis of gene expression, knockdown using interfering RNA (RNAi), and transformation rescue. 2. Determine the nature of the genes underlying sexual conflict and sperm competition in C. remanei, a strictly outcrossing species of Caenorhabditis that is emerging as a model organism for evolutionary ecology research. Preliminary results indicate the presence of sperm competition and sexual conflict within this species. Depending on female and male genetic backgrounds, male mating can reduce female longevity by as much as 33% in a strain specific manner. Crosses among strains divergent for male effects on female longevity and sperm competitive ability will be used to identify the genetic basis of these male mating ability associated traits. Relevance: Understanding the genetic basis of complex traits, including human conditions such as heart disease, obesity, and mental illness known to be influenced by a large number of interacting genes, is one of the major challenges of modern biology. This work serves as a model of how one can utilize high-throughput genomic approaches to understand the molecular genetic basis of complex traits. Further, sex specific effects and interactions are ubiquitous features of all organisms, including humans, and understanding their genetic basis can yield insights into the forces structuring what is certain to be a large fraction of the genome.