Neuropeptide Regulation of Mosquito Host-Seeking Behavior

描述（由申请人提供）：神经肽是从蠕虫到人类神经系统功能的重要调节剂。由专门的神经分泌细胞产生，它们被控制释放到局部脑回路和循环系统中，对化学感觉、摄食、昼夜节律、睡眠、社会行为和一般生理稳态有深远的影响。在埃及伊蚊中，神经肽与对宿主吸引力的周期性行为抑制有关，这种抑制在雌性吸血后持续三天。虽然糖是足够的生存，一旦雌蚊达到生殖成熟，它们需要血来产卵。吸引人类宿主的信号，包括体温、二氧化碳、体味和皮肤上的味道信号，只有在雌性需要血液蛋白来产卵时才会表现出来。在吸血后大约72小时内，女性对人类的吸引力会被抑制。这种循环在大约一个月的成人寿命中重复多达10次。传染病在人类中的传播是这种供血循环的副产品，因此阐明宿主抑制的机制具有重要的健康意义。本研究的广泛、长期目标是全面了解蚊子神经肽和神经肽受体的功能，并确定吸血后强烈抑制寻宿主行为的机制。该提案有三个互锁的特定目的：(1)注释埃及伊蚊的神经肽和神经肽受体基因，并定义配体-受体相互作用。(2)鉴定血食后介导寻宿主抑制的神经肽信号通路。(3)开发研究蚊子神经肽信号的基因工具箱。这项工作是创新的，因为它使用高通量384孔细胞筛选与遗传编码钙指示剂去孤儿神经肽受体；探索血餐后宿主抑制机制的药理学和神经遗传学工具；并优化了CRISPR/Cas9基因组编辑，生成了大量突变株，每个突变株都缺乏给定的神经肽或神经肽受体。该项目将对这一重要病媒昆虫神经肽受体的配体和生物学功能产生重要的见解，并将为调节蚊子的寻宿主行为提供新的工具。该项目开发的菌株将成为研究神经肽信号生理功能的宝贵资源。

DESCRIPTION (provided by applicant): Neuropeptides are important modulators of nervous system function from worms to humans. Produced by specialized neurosecretory cells, their controlled release into local brain circuits and the circulatory system has profound effects on chemosensation, feeding, circadian rhythms, sleep, social behavior, and general physiological homeostasis. In Aedes aegypti mosquitoes, neuropeptides have been implicated in the cyclical behavioral suppression of host attraction that lasts for three days after the female has taken a blood-meal. Although sugar- feeding is sufficient for survival, once female mosquitoes reach reproductive maturity, they require a blood-meal to develop eggs. Attraction to human host cues, including body heat, carbon dioxide, body odor, and taste cues on skin, is only expressed when the female needs blood protein for egg production. For approximately 72 hours after a blood-meal, female attraction to humans is suppressed. This cycle repeats up to 10 times for the approximately one month adult life-span. The spreading of infectious diseases among humans is a by- product of this blood-feeding cycle, so elucidating the mechanisms of host suppression has great health relevance. The broad, long-term objectives of this research are to gain a comprehensive understanding of mosquito neuropeptide and neuropeptide receptor function and to define the mechanisms that mediate the strong suppression of host-seeking behavior after a blood-meal. The proposal has three interlocking specific aims: (1) Annotate neuropeptide and neuropeptide receptor genes in Aedes aegypti and define ligand-receptor interactions. (2) Identify neuropeptide signaling pathways that mediate host-seeking suppression after a blood-meal. (3) Develop a genetic tool-kit for studying neuropeptide signaling in the mosquito. The work is innovative because it uses high-throughput 384-well cell-based screening with a genetically-encoded calcium indicator to deorphanize neuropeptide receptors; pharmacological and neurogenetic tools to probe mechanisms underlying post blood-meal host-suppression; and optimized CRISPR/Cas9 genome-editing to generate a large collection of mutant strains, each lacking a given neuropeptide or neuropeptide receptor. The project will yield significant insights into the ligands and biological function of neuropeptide receptors in this important disease vector insect and will provide new tools to regulate mosquito host-seeking behavior. The strains developed under this project will be a valuable community resource for investigating the physiological functions of neuropeptide signaling.