Genomic Conflicts and Reproductive Isolation

该项目旨在测试生殖隔离进化的两种遗传机制。一种可能是自私基因通过精子竞争传播，而另一种可能是促进雄性受精的拮抗基因对雌性繁殖有负面影响。这两种过程都可能导致种群内的遗传军备竞赛，这可能导致种群间的杂交不育。自私基因假说将通过定位杂交不育因素来确定它们是否靠近影响自私X染色体传播的因素，并通过比较染色体区域之间的DNA序列进化来验证。通过比较雄性和雌性生殖和非生殖特征的进化速度，以及确定精子竞争能力是否取决于种群间的遗传差异，将对拮抗基因假说进行检验。确定生殖隔离是如何演变的，对于理解物种起源至关重要。这里提出的研究是值得注意的，因为生殖隔离的其他遗传机制将被评估，并将利用来自东南亚的杆眼蝇属（Cyrtodiopsis）的分离种群。柄眼蝇是这项工作的理想选择，因为具有杂交不育性、自私性染色体和可变遗传分化的种群可供研究。

This project aims to test two alternative genetic mechanisms for the evolution of reproductive isolation. One possibility assumes that selfish genes compete for transmission by sperm while an alternative assumes that antagonistic genes that facilitate male fertilization have negative effects on female reproduction. Both of these processes can cause genetic arms races within populations, which may cause hybrids between populations to be sterile. The selfish gene hypothesis will be tested by locating hybrid sterility factors to determine if they are near those that influence transmission of selfish X chromosomes and by comparing DNA sequence evolution between chromosome regions. The antagonistic gene hypothesis will be tested by comparing the rate of evolution of reproductive to nonreproductive traits in males and females and by determining if sperm competitive ability depends on genetic divergence between populations.Determining how reproductive isolation evolves is essential for understanding the origin of species. The research proposed here is notable because alternative genetic mechanisms for reproductive isolation will be evaluated and will utilize isolated populations of stalk-eyed flies, genus Cyrtodiopsis, from southeast Asia. Stalk-eyed flies are ideally suited for this work because populations that exhibit hybrid sterility, selfish sex chromosomes and variable genetic divergence are available for study.