Gene expression and functional evolution in the Drosophila female reproductive tract

项目摘要 果蝇雌性生殖道在形态上和功能上都很复杂，作为果蝇进行生殖活动的竞技场， 多个男性射精和女性产品之间的高风险相互作用发挥出来，它也可能是主题 强大而矛盾的选择压力。此外，生殖道是级联反应的起始部位， 交配后女性生物学反应，从隔离精子和产卵到神经系统的变化， 基因表达和行为。这些过程中的许多过程可能经历性拮抗选择， 结果影响到两性不同的生殖利益。尽管如此，研究投资在较低的 雌性生殖道，包括精子储存器官和雌性附腺，严重滞后 对雄性生殖组织的投资。例如，贮精器、子宫和女性附件 腺体已被排除在每一个主要的社区转录组分析;资源，如Gal-4驱动程序 或标记基因标签一般不存在这些组织;和几个器官的功能和进化 描述不好。这些遗漏限制了对一系列重要问题的深入了解，包括 机制和进化的女性射精相互作用，在生殖组织的快速进化的程度 及其驱动因素，以及性冲突的结果。然而，这些遗漏也凸显了新的机会， 在领先的模式生物中使用成熟的技术进行低障碍、高回报的研究， 这一建议继续下去。首先，对来自两个不同的自然群体的交配和未交配的雌性进行单细胞测序， 种群将被用于1）首次表征女性生殖道中的细胞类型多样性 和2）在细胞水平上测量5个体细胞雌性生殖组织中的基因表达和差异。 具体目标（1）。这些数据也将检验女性中基因表达的假设， 生殖组织由于与精液蛋白的共同进化相互作用而迅速分化。接下来是基因 重要功能进化的候选者将被淘汰并进行生殖评估 方面的影响.特异性目的2检测在贮精器中表达的7种受体的无效等位基因，并显示 快速分化的迹象，以检验这些受体介导雌性交配后的假设 应答Specific Aim 3使用一组在贮精器中具有新表达的从头基因， 探索基因诞生和功能整合的神秘过程。具体来说， 基于转录本长度，表达水平， 结构复杂性和其他指标，将被淘汰，并评估对女性生殖的影响， 功能

PROJECT SUMMARY The Drosophila female reproductive tract is morphologically and functionally complex, and as the arena where high-stakes interactions among multiple male ejaculates and female products play out, it is also likely subject to strong and conflicting selection pressures. Moreover, the reproductive tract is the initiation site for a cascade of post-mating responses in female biology, from sequestering sperm and ovipositing to changes in neural gene expression and behavior. Many of these processes may undergo sexually antagonistic selection, as outcomes affect the sexes’ divergent reproductive interests. Nevertheless, research investment in the lower female reproductive tract, including the sperm storage organs and the female accessory glands, severely lags investment in male reproductive tissues. For example, the seminal receptacle, uterus, and female accessory glands have been excluded from every major community transcriptome analysis; resources like Gal-4 drivers or marker gene labels generally do not exist for these tissues; and the function and evolution of several organs remain poorly described. These omissions limit insight into a range of important questions, including the mechanisms and evolution of female-ejaculate interactions, the extent of rapid evolution in reproductive tissues and its drivers, and the outcomes of sexual conflict. Yet these omissions also highlight an opportunity for new low-barrier, high return investigations using well-established technologies in a leading model organism, which this proposal pursues. First, single-cell sequencing of mated and unmated females from two diverged natural populations will be used to 1) characterize cell-type diversity in the female reproductive tract for the first time and 2) measure gene expression and divergence in the 5 somatic female reproductive tissues at cellular resolution (Specific Aim 1). These data will also test the hypothesis that gene expression in female reproductive tissues diverges rapidly owing to coevolving interactions with seminal fluid proteins. Next, genes that are candidates for important functional evolution will be knocked out and evaluated for reproductive effects. Specific Aim 2 tests null alleles of 7 receptors that are expressed in the seminal receptacle and show indications of rapid divergence, to test the hypothesis that these receptors mediate female post-mating responses. Specific Aim 3 uses a set of de novo genes with novel expression in the seminal receptacle to explore the mysterious process of gene birth and functional integration. Specifically, the de novo gene candidates that appear most likely to be functionally integrated based on transcript length, expression level, structural complexity, and other metrics, will be knocked out and evaluated for effects on female reproductive function.