Actions of Seminal Proteins in Mated Drosophila Females

摘要 从昆虫到哺乳动物，精液蛋白(SFP)显著影响着 交配的雌性，雌性体内精子的储存和释放，甚至(在小鼠中) 后代。特定SFP异常的男性是不育或不育的，包括人类。一些SFP紧密绑定在一起 对精子；其他的在精浆中是游离的。然而，尽管它们在生殖中很重要，但人们对它们知之甚少。 SFP究竟如何影响雌性或雌性精子的行为。重要的是，许多SFP 进化迅速，与分子/进化性冲突中的角色一致。了解功能 对SFP及其在雌性体内相互作用的蛋白质的进化的限制将指导未来 关于SFP在人类生育中的作用的调查。 我们将结合分子遗传学和功能研究方法来研究：(1)SFP是如何与 女性分子引发生殖反应以及(2)SFP如何与精子结合以调节其 影响，以及这两种功能是如何演变的。我们将使用以下工具调查这些问题 果蝇，一个主要的SFP功能的遗传模型系统，拥有丰富的资源 进化论比较。重要的是，果蝇SFP在分子和现象学上有许多相似之处。 对哺乳动物的影响。 目的1重点研究卵蛋白，它通过诱导神经元八胺能信号来刺激排卵。 这种信号调节女性生殖道的肌肉收缩，放松输卵管和 提高排卵率。使用遗传筛选和蛋白质-蛋白质共同进化的签名，我们有 确定了女性卵蛋白受体(OVR)的有力候选者。我们将测试它们的卵蛋白结合力 然后确定OVR的定位，以确定卵泡作用的部位。然后，我们将检查不同之处 物种的卵黄蛋白介导卵子的作用和OVR的结合，以阐明其功能的进化。 在目标2中，我们将重点研究与精子结合的精液蛋白，我们已经通过它们的共同进化来鉴定它们。 或者用蛋白质组学的方法。我们最近的数据显示，SFP启动精子与关键的SFP结合，称为Sex 多肽。我们将询问哪些精液蛋白在这个启动途径中起作用，哪些是独立起作用的。 那条小路上。我们还将调查女性分泌物是否也参与了引爆。最后，我们会 确定精子结合的SFP子集的功能在多大程度上是相关的 果蝇物种。 阐明SFP如何在分子水平上与女性相互作用并影响女性，以及这些 交互作用的发展，对于理解和诊断基于SFP的不育症非常重要，在考虑 将受益于纳入关键的SFP的辅助生殖技术的战略，以及 开发新的方法来控制传播登革热、寨卡病毒和疟疾等严重疾病的双翅目昆虫。

SUMMARY From insects to mammals, seminal fluid proteins (Sfps) significantly affect the reproductive physiology of mated females, the storage and release of sperm inside females, and (in mice) even the phenotype of progeny. Males abnormal for specific Sfps are sterile or subfertile, including in humans. Some Sfps bind tightly to sperm; others are free in seminal plasma. Yet despite their importance in reproduction, little is known about exactly how Sfps act to influence the female or the behavior of sperm in females. Importantly, many Sfps evolve rapidly, consistent with roles in molecular/evolutionary sexual conflicts. Understanding functional constraints on the evolution of Sfps and the proteins with which they interact in females will guide future investigations into Sfp actions in human fertility. We will combine molecular genetic and functional approaches to investigate: (1) how Sfps interact with female molecules to elicit reproductive responses and (2) how Sfps associate with sperm to mediate their effects, as well as how both types of function have evolved. We will investigate these questions using Drosophila, a premier genetic model system for dissecting Sfp function, with extensive resources for evolutionary comparisons. Importantly, Drosophila Sfps have many molecular and phenomenological parallels to those of mammals. Aim 1 focuses on ovulin, which stimulates ovulation by inducing neuronal octopaminergic signaling. This signaling regulates muscle contraction in the female reproductive tract, relaxing the oviducts and increasing ovulation rate. Using genetic screens and signatures of protein-protein coevolution, we have identified strong candidates for the female’s receptor for ovulin (OvR). We will test these for ovulin binding and then determine OvR localization, to pinpoint the site of ovulin action. We will then examine how well different species’ ovulins mediate ovulin action and OvR binding, to elucidate the evolution of their function. In Aim 2 we will focus on seminal proteins that bind to sperm, which we have identified by their coevolution or by proteomic methods. Our recent data show that Sfps prime sperm for binding to the critical Sfp called Sex Peptide. We will ask which seminal proteins function within this priming pathway and which act independently of that pathway. We will also investigate whether female secretions are also involved in priming. Finally, we will determine the extent to which the functions of a subset of sperm-bound Sfps are conserved across related Drosophila species. Elucidating how Sfps interact with and affect the female at the molecular level, as well as how these interactions evolve, is important for understanding and diagnosing Sfp-based infertilities, in considering strategies for assisted reproductive technologies that would benefit from inclusion of critical Sfps, and for developing new ways to control dipteran insects that transmit serious diseases like dengue, Zika, and malaria.