The genetic and neural basis of female behaviours in Drosophila.

识别复杂行为变异的潜在遗传和神经基础仍然是行为生物学的主要目标和挑战。提出的研究计划确定单个遗传变化，单个神经元和复杂行为变化背后的神经回路。我们利用果蝇模型系统中强大的遗传工具，专注于女性配偶拒绝行为和女性侵略的一些鲜为人知但却至关重要的特征。雄性动物的交配行为和攻击行为在遗传和神经水平上得到了广泛的研究，但对雌性动物的研究却很少。由于雌性的选择往往是决定交配是否发生的决定性因素，包括阻止近亲物种之间的交配，而雌性的攻击性对资源获取和繁殖可能很重要，这一基础自然科学知识的差距限制了我们对关键行为途径的进化以及这些途径对物种形成的影响做出更大规模进化理论的能力。这一差距也阻碍了对男性和女性复杂生殖行为形成过程中是否存在差异或凝聚力的探索。为了弥补这一差距：(1)我们将使用有针对性的遗传变化来确定女性接受性变异的特定遗传多态性，重点关注我们之前确定的影响物种特异性雌性配偶拒绝行为变异的两个基因。(2)我们将通过靶向候选神经元亚群的转录物敲低，确定这两个候选基因通过哪些神经元影响女性排斥反应。(3)我们将使用尖端的工具来识别我们最近发现的雌性排斥通路的上游和下游电路，涉及一对章鱼胺神经元，当神经元沉默时，它们会诱导活跃的雌性排斥。(4)我们将使用一系列果蝇工具来识别雌性特异性攻击的神经递质和电路，重点关注我们最近发现的一小群神经元，当这些神经元被过度激活时，它们会诱导雌性特异性攻击；这些相同的神经元诱导雄性求偶。

Identifying the underlying genetic and neural basis of variation in complex behaviour remains a primary goal, and challenge, in behavioral biology. The proposed research program identifies single genetic changes, individual neurons, and the neural circuitry underlying variation in complex behavior. We focus on the poorly-understood, yet critical, traits of female mate rejection behaviour and female aggression, using the powerful genetic tools available within the Drosophila model system. The traits of mating behavior and aggression have been extensively studied at the genetic and neural level in males, but are poorly understood in females. Since female choice is more often the deciding factor in whether mating occurs, including preventing matings between closely-related species, and female aggression can be important for resource acquisition and reproduction, this gap in fundamental natural sciences knowledge limits our ability to make larger-scale evolutionary theories about the evolution of critical behavioural pathways and the effect of those pathways on speciation. This gap also prevents an exploration of whether there is divergence or cohesiveness in the formation of complex reproductive behaviours in males and females. To rectify this gap: (1) We will use targeted genetic changes to determine the specific genetic polymorphisms that underlie variation in female receptivity, focusing on two genes we previously identified as affecting variation in species-specific female mate rejection behavior. (2) We will identify the neurons that these two candidate genes are acting through to affect female rejection by targeting transcript knockdown in subsets of candidate neurons. (3) We will use cutting-edge tools to identify the upstream and downstream circuitry of a female rejection pathway we recently identified involving a single pair of octopamine neurons that induce active female rejection when the neurons are silenced. (4) We will use an array of Drosophila tools to identify the neurotransmitters and circuitry of female-specific aggression, focusing on a small cluster of neurons we recently identified that induce female-specific aggression when these neurons are hyper-activated; these same neurons induce courtship in males. Completion of these four objectives will provide the first characterization of a gene for female behaviours responsible for isolating species, the first identification of neurons affecting species isolation, the first fine-scale characterization of neurons and circuitry in the central nervous system for female mate rejection behavior, and the first characterization of neurons and circuitry for female-specific aggression. Understanding the genetic and neural basis of these key female-specific behaviours is essential if we are to have a complete perspective of how complex behaviours are generated.