Molecular Genetics of Olfaction in Drosophila

这是福格蒂国际项目合作研究的修订申请。父母资助的目的是研究黑腹果蝇气味引导行为的遗传结构，这种行为对生存和繁殖至关重要。在评估任何复杂性状的遗传基础时，重要的是要区分促成性状表现的基因和促成性状自然发生的表型变异的基因子集，因为后者包含作为进化基础的多态性。亲本补助金的具体目的完全集中在成虫身上，即生命周期的生殖阶段。目前的Fogarty应用程序提出鉴定有助于幼虫气味引导行为的新基因，并评估这些基因中哪些可能有助于自然种群的表型可塑性。这项Fogarty提案的具体目的是：(1)鉴定导致黑腹果蝇幼虫气味引导行为的基因；(2)鉴定那些在Specific Aim 1中鉴定的基因，这些基因有助于自然种群中幼虫嗅觉行为的表型变异，并形成适应性进化的基础。将筛选共等基因P元素插入系，以确定影响幼虫嗅觉行为的基因，并将负责幼虫嗅觉障碍的候选基因与先前从相同P元素插入系中发现的影响成年果蝇气味引导行为的候选基因进行比较。将来自阿根廷8个不同自然种群的单个染色体替换为等基因背景，并进行定量互补测试，以评估特异性目标1中鉴定的多达12个幼虫基因，这些基因是否有助于嗅觉行为的自然变异。所提出的方法将大大延长亲本拨款，并且在化学感觉的背景下，它将定量遗传策略直接与分子生态学相结合，这是创新的。

This is a revised application for collaborative research under the Fogarty International Program. The aim of the parent grant is to investigate the genetic architecture of odor-guided behavior in Drosophila melanogaster, a behavior which is essential for survival and reproduction. When assessing the genetic basis of any complex trait, it is important to distinguish genes that contribute to manifestation of the trait and a subset of these genes that contribute to naturally occurring phenotypic variation of the trait, as the latter harbor polymorphisms that serve as the substrate for evolution. The specific aims of the parent grant focus entirely on adult flies, i.e. the reproductive phase of the life cycle. The present Fogarty application proposes to identify novel genes that contribute to larval odor-guided behavior and to assess which of these genes may contribute to phenotypic plasticity in natural populations. The specific aims of this Fogarty proposal are: (1) Identification of genes that contribute to odor-guided behavior in Drosophila melanogaster larvae; and, (2) Identification of those genes, identified in Specific Aim 1, that contribute to phenotypic variation for larval olfactory behavior in natural populations and form the substrate for adaptive evolution. Co-isogenic P- element insertion lines will be screened to identify genes that affect olfactory behavior in larvae, and candidate genes responsible for larval smell impairment will be compared to those that affect odor-guided behavior in adult flies identified earlier from a screen of the same P-element insertion lines. Individual chromosomes from eight diverse natural populations of D. melanogaster from Argentina will be substituted into an isogenic background and quantitative complementation tests will be performed to assess for up to 12 larval genes identified in Specific Aim 1 whether these genes contribute to natural variation in olfactory behavior. The proposed approach will significantly extend the parent grant and is innovative in that it combines quantitative genetic strategies directly with molecular ecology in the context of chemosensation.