The behaviors of closely related species can be remarkably different, and these differences have important ecological and evolutionary consequences. Although the recent boom in genotype-phenotype studies has led to a greater understanding of the genetic architecture and evolution of a variety of traits, studies identifying the genetic basis of behaviors are, comparatively, still lacking. This is likely because they are complex and environmentally sensitive phenotypes, making them difficult to measure reliably for association studies. The Drosophila species complex holds promise for addressing these challenges, as the behaviors of closely related species can be readily assayed in a common environment. Here, we investigate the genetic basis of an evolved behavioral difference, pupation site choice, between Drosophila melanogaster and D. simulans. In this study, we demonstrate a significant contribution of the X chromosome to the difference in pupation site choice behavior between these species. Using a panel of X-chromosome deficiencies, we screened the majority of the X chromosome for causal loci and identified two regions associated with this X-effect. We then collect gene disruption and RNAi data supporting a single gene that affects pupation behavior within each region: Fas2 and tilB. Finally, we show that differences in tilB expression correlate with the differences in pupation site choice behavior between species. This evidence associating two genes with differences in a complex, environmentally sensitive behavior represents the first step toward a functional and evolutionary understanding of this behavioral divergence.

中文翻译：

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行为进化的场所：Fas2和tilB是果蝇和拟蝇（D. simulans）化up位点选择行为差异的证据。

密切相关的物种的行为可能存在显着差异，这些差异具有重要的生态和进化意义。尽管最近基因型-表型研究的蓬勃发展使人们对遗传结构和各种性状的进化有了更深入的了解，但是，仍然缺乏确定行为遗传基础的研究。这可能是因为它们是复杂的且对环境敏感的表型，从而使其难以可靠地进行关联研究的测量。果蝇物种复合体有望解决这些挑战，因为可以在共同的环境中轻松分析密切相关物种的行为。在这里，我们调查了果蝇和拟南芥之间进化的行为差异，化up位点选择的遗传基础。在这项研究中，我们证明了X染色体对这些物种之间化site位点选择行为的显着贡献。使用一组X染色体缺陷，我们针对因果位点筛选了X染色体的大部分，并确定了与该X效应相关的两个区域。然后，我们收集支持单个基因的基因破坏和RNAi数据，该基因影响每个区域内的化up行为：Fas2和tilB。最后，我们表明tilB表达的差异与物种之间化up位点选择行为的差异相关。这一证据将两个基因与复杂的，对环境敏感的行为的差异相关联，是朝着对这种行为差异进行功能性和进化性理解的第一步。我们证明了X染色体对这些物种化up位点选择行为差异的重大贡献。使用一组X染色体缺陷，我们针对因果位点筛选了X染色体的大部分，并确定了与该X效应相关的两个区域。然后，我们收集支持单个基因的基因破坏和RNAi数据，该基因影响每个区域内的化up行为：Fas2和tilB。最后，我们表明tilB表达的差异与物种之间化up位点选择行为的差异相关。这一证据将两个基因与复杂的，对环境敏感的行为的差异相关联，是朝着对这种行为差异进行功能性和进化性理解的第一步。我们证明了X染色体对这些物种化up位点选择行为差异的重大贡献。使用一组X染色体缺陷，我们针对因果位点筛选了X染色体的大部分，并确定了与该X效应相关的两个区域。然后，我们收集支持单个基因的基因破坏和RNAi数据，该基因影响每个区域内的化up行为：Fas2和tilB。最后，我们表明tilB表达的差异与物种之间化up位点选择行为的差异相关。这一证据将两个基因与复杂的，对环境敏感的行为的差异相关联，是朝着对这种行为差异进行功能性和进化性理解的第一步。