The genetics of hybrid male sterility in Drosophila virilis and D. americana

描述（由申请人提供）：总的来说，拟议研究的目标是了解受精卵后生殖隔离的遗传基础。本研究将解决两个基本问题：1)杂种不亲和性是如何在遗传和发育途径中产生的；2)不亲和性等位基因是如何在自然种群中建立起来的。这项研究的第一部分将使用高分辨率的基因图谱来发现和描述导致雄性雄性不育的基因，这是两个处于分化早期阶段的物种。经典研究表明，当两种植物杂交时，雄性雄性不育的因素在种内均表现出明显的异质性。因此，这个系统提供了一个机会，以确定那些基因杂交不相容首次出现。此外，了解杂交男性不育的遗传基础可能有助于了解人类不育的遗传学。本研究的第二部分将采用比较作图的方法来研究美洲稻属自然种群内和种群间杂交雄性不育基因的变异。最后，本研究旨在采用分子群体遗传学的方法来研究杂交不亲和性和物种分化的进化动力学。

DESCRIPTION (provided by applicant): Broadly, the goal of the proposed study is to understand the genetic basis of postzygotic reproductive isolation. Two fundamental problems will be addressed by this study: 1) how hybrid incompatibilities arise within genetic and developmental pathways, and 2) how incompatibility alleles become established in natural populations. The first part of the proposed study will use high-resolution genetic mapping to find and characterize genes that cause hybrid male sterility between Drosophila virilis and D. americana, two species in the early stages of divergence. Classic studies have shown that both D. virilis and D. americana exhibit substantial within-species heterogeneity for factors that contribute to hybrid male sterility when the two species are crossed. Therefore, this system provides an opportunity to identify those genes at which hybrid incompatibilities first appear. In addition, understanding the genetic basis of hybrid male sterility may shed light on the genetics of human infertility. The second part of the proposed study will take a comparative mapping approach to examine variation for hybrid male sterility genes within and between natural populations of D. americana. Ultimately, this research aims to take a molecular population genetics approach to investigate the evolutionary dynamics of hybrid incompatibility and species divergence. Some of the hybrid male sterility genes discovered in Drosophila might show functional conservation with human fertility genes. The proposed study is relevant to public health because studies of Drosophila fertility can be applied to understanding the genetics of human fertility.