Assessing the generality of sexual conflict in new gene evolution in Drosophila

项目总结 在有性繁殖物种中，雄性和雌性具有不同的形态、行为和 生殖策略，以达到各自的适合度最佳，同时共享大致相似的基因组。这些 差异可能导致性别冲突，其中特定特征的存在可能导致相反的适合度 对男性和女性的影响。在局灶性冲突(ISC)中，在一个基因座内存在单一基因 可以增加一种性别的适合度，同时降低另一种性别的适合度。 有广泛的证据表明，包括人类在内的许多动物中都存在ISC，而且这种存在 性二形性的研究表明，ISC的某些方面是可以解决的。虽然之前的理论和基因 关联研究已经帮助预测了ISC及其缓解策略，但我们仍然缺乏经验 ISC涉及哪些基因的证据，它们的作用，以及它们对性别特有适合度的直接影响 进化论。 最近，我们实验室发表了第一个直接证据，表明新的基因进化是通过基因来实现的。 ISC决议中的重复。我们发现，最近在果蝇体内复制的一对基因迅速 男性和女性的累积序列变化和获得性基本、性别特异性功能 支持之前的理论预测的生殖。正如它所显示的那样，这是一项突破性的发现 ISC的分辨率可以推动新的基因进化。然而，这一单一案例研究的一般性仍然存在。 未知。 这项提议的目的是定义性别冲突驱动的新基因进化的共性。 我假设小灶内性冲突的解决可以通过快速的 获得有助于特定性别健康的新功能。我将在两个主要方面检验我的假设 目标。首先，我将使用CRISPR-Cas9辅助的反向遗传学方法来评估36 新复制的基因通过特定性别的适合度分析。到目前为止，我已经敲除了七个新的基因 研究发现，三种基因的功能丧失突变降低了雄性或雌性果蝇的生育力，这表明它们 可能有助于解决一场祖传的性冲突。第二，我将进行更深层次的 利用组织和单细胞的RNA测序，对目标1中检测的五个基因进行功能分析 水平，以确定在解决性冲突中需要新基因功能的途径和细胞类型。我的 拟议的研究将基于CRISPR-Cas9的反向遗传学方法与转录组图谱相结合，以 定义ISC驱动的新基因进化的共性，以及这些新基因如何促进性别特异性 调停或解决性冲突的功能。

PROJECT SUMMARY In sexually reproducing species males and females have divergent morphologies, behaviors, and reproductive strategies to reach their respective fitness optima while sharing a largely similar genome. These differences can cause sexual conflict, wherein the presence of a particular trait can result in opposite fitness effects in males and females. In intralocus sexual conflict (ISC) the presence of a single gene within a locus can increase the fitness of one sex while decreasing the fitness of the other. There is widespread evidence of ISC occurring in many animals, including humans, and the presence of sexual dimorphism suggests that some aspects of ISC can be resolved. While previous theoretical and gene association studies have helped predict ISC and strategies for its mitigation, we still have little empirical evidence of which genes are involved in ISC, their roles, and their direct impacts on sex-specific fitness in evolution. Recently, our laboratory published the first direct evidence implicating new gene evolution through gene duplication in the resolution of ISC. We found that a pair of recently duplicated genes in Drosophila had quickly accumulated sequence changes and acquired essential, sex-specific functions in male and female reproduction—supporting previous theoretical predictions. This was a groundbreaking finding as it suggests that ISC resolution can drive new gene evolution. However, the generality of this single case study remains unknown. The objective of this proposal is to define the generality of sexual conflict-driven new gene evolution. I hypothesize that intralocus sexual conflict resolution can drive the evolution of new genes through rapid acquisition of novel functions which contribute to sex-specific fitness. I will test my hypothesis in two major Aims. First, I will use a CRISPR-Cas9-aided reverse genetic approach to assess the genetic necessity of 36 newly duplicated genes through sex-specific fitness assays. Thus far I have knocked out seven new genes and found that loss-of-function mutations in three genes reduced the fertility of male or female flies, suggesting they may have contributed to the resolution of an ancestral sexual conflict. Second, I will conduct a deeper functional analysis on five genes examined in Aim 1, using RNA sequencing at both the tissue and single cell levels, to identify pathways and cell types that require new gene functions in resolving sexual conflict. My proposed research combines a CRISPR-Cas9-based reverse genetics approach with transcriptome profiling to define the generality of ISC-driven new gene evolution and how these new genes facilitate sex-specific functions to mediate or resolve sexual conflict.