Genetic Analysis of Complex Adaptive Traits

目前，关于生物体进化适应时会发生何种类型的遗传变化，还没有足够的可靠数据。这些数据只能来自对自然适应性的高分辨率遗传分析。果蝇（Drosophila sechellia）是唯一适合进行这种分析的物种，因为它可以在基因上进行操纵，并且具有无可争议的适应性。作为一种遗传模式物种黑腹蝇的近亲，黑腹蝇已经适应了食用对其他果蝇有毒的Morinda citrifolia果实。该基金的前两个实验是对d.s hellia适应性的深入遗传分析。参与这种适应的基因将被精确地绘制出来，并对它们的影响进行估计。这些数据是鉴定和克隆适应性等位基因的必要的第一步。最后的实验将通过人工进化果蝇相关物种的抗性来确定遗传变异与新突变在适应进化中的相对重要性。这项拟议中的研究将帮助我们了解生物体如何在基因上改变以应对环境变化。具体来说，这笔拨款将影响我们对昆虫如何进化出对植物产生的杀虫剂的抗性的理解，并将深入了解昆虫如何选择它们赖以为生的植物。

Currently, there is not enough good data on what types of genetic changes occur when organisms evolve an adaptation. This data can only come from high-resolution genetic analyses of natural adaptations. The fruitfly, Drosophila sechellia, is uniquely suited for such an analysis as it can be manipulated genetically and has an indisputable adaptation. A close relative of D. melanogaster, a genetic model species, D. sechellia has adapted to consuming the fruit of Morinda citrifolia, a fruit that is toxic to other fruitflies. The first two experiments in this grant are in-depth genetic analyses of D. sechellia's adaptation. The genes involved in this adaptation will be precisely mapped and their effects estimated. This data is a necessary first step towards the identification and cloning of the adaptive alleles. The final experiment will determine the relative importance of standing genetic variation versus new mutations in the evolution of an adaptation by artificially evolving resistance in related species of fruitflies.The proposed research will help us understand how organisms genetically change in response to environmental change. Specifically, this grant will impact our understanding of how insects evolve resistance to plant produced pesticides and will give insight into how insects choose the plants upon which they feed.