MOLECULAR EVOLUTION OF SEX DETERMINATION

这项拟议研究的长期目标是了解苍蝇和其他类群中性别决定途径的功能分歧和保守性。第一个具体目标是检验这样一个假设，即在层次结构中最后起作用的那些通路组件最有可能是保守的。第二个具体目的是研究分子功能的进化获得。第三个具体目标是检验关于性别决定层次结构开始附近的物种内变异基因的预期水平的相互竞争的假说，并与作用于层次结构末尾的基因的物种内变异水平进行比较。这项研究的价值在于，它将阐明遗传途径涉及的过程，从而产生一个概念框架，用于将果蝇等模型系统的知识应用于包括人类在内的其他有机体的发育。前两个具体目标将通过克隆和鉴定中间性和决定机制的同源性来实现。为了实现第三个特定目标，将在一组不同的野生型苍蝇品系中引入两性突变，以揭示涉及性别决定的相互作用基因的遗传变异。

The long-term objective of the proposed research is to understand the functional divergence and conservation of the sex-determination pathway in flies and other taxa. The first specific aim is to test the hypothesis that those components of the pathway that act last in the hierarchy are most likely to be conserved. The second specific aim is to study the evolutionary acquisition of molecular function. The third specific aim is to test competing hypothesis about the expected level of within species variation ingenues acting near the beginning of the sex-determination hierarchy, as compared with the level of within species variation in genes acting near the end of the hierarchy. The value of this research is that it will illuminate the process by which genetic pathways involve, and thereby produce a conceptual framework for applying knowledge of model systems like Drosophila to the development of the other organisms, including humans. The first two specific aims will be achieved by cloning and characterizing homologies of the intersex and determining mechanisms. To achieve the third specific aim, a mutation in hermaphrodite will be introgressed into a diverse set of wildtype fly strains, to uncover genetic variation in interacting genes involved in sex determination.