Molecular basis of egg-laying across mosquitoes

世界上有一半的人口面临感染蚊子传播的病毒性疾病的风险，据估计，这一数字在未来50年将增加10亿。选择一个合适的产卵（产卵）地点对蚊子等不需要后续亲代照顾的动物的适应性至关重要。我提出的发现基金的主要目标是在分子遗传学和神经回路水平上了解不同种类的蚊子是如何决定在哪里产卵的。这项工作将有助于确定为什么一些蚊子在全球范围内传播并继续传播，而另一些蚊子仍然局限于特定的生态位，这对理解基本的蚊子生物学以及制定有针对性的控制策略具有重要意义。埃及伊蚊起源于撒哈拉以南非洲，但现在在全球范围内广泛而迅速扩大，它们主要以两种方式利用人类：1)专门以人类血液为食，用于产卵；2)在与人类住区有关的淡水小体中产卵，如饮用水容器、轮胎或废弃建筑。Ae。埃及伊蚊幼虫在海水高于10%的微咸水中死亡，成年雌蚊避免在这些盐度中产卵。相比之下，东哥伊蚊在城市环境中找不到，在北美西部和亚洲沿岸的咸水和半咸水岩池中繁殖，其幼虫能够忍受从淡水到300%海水的盐度。人们对Ae是如何形成的知之甚少。它们选择产卵地点，尽管生活史特征不同，从热带到亚北极分布，但它们的活动范围仍然局限于沿海地区。本研究旨在探讨不同种类伊蚊产卵策略、幼虫生理和生境利用灵活性的差异。埃及伊蚊和伊蚊。目的1：确定指导东哥伊蚊产卵偏好的行为策略。埃及伊蚊和伊蚊。togoi使用定量行为分析和人工选择目的3：利用CRISPR/Cas9引入新的等位基因，确定转移产卵偏好的因果分子机制和神经回路，并阐明回路的解剖学和功能。本研究项目将通过结合比较方法，揭示蚊子栖息地开发背后的遗传和行为适应有针对性的基因操作。在快速变化的世界中，了解昆虫的神经系统如何适应并允许开发新的生态位对于预测和预防农业有害生物物种和人类和动物病原体媒介的范围增加至关重要。

Half the world's population is at risk of contracting mosquito-borne viral disease and it is estimated that this number will grow by 1 billion over the next 50 years. Selecting an appropriate oviposition (egg-laying) site is critical to fitness in animals like mosquitoes that perform no subsequent parental care. The broad objective of my proposed Discovery Grant is to understand, at the molecular genetic and neural circuit level, how different species of mosquito decide where to oviposit. This work will help determine why some mosquitoes have spread, and continue to spread, across the globe while others remain restricted to specific ecological niches with important implications for understanding basic mosquito biology as well as developing targeted control strategies. Aedes aegypti originated in sub-Saharan Africa but are now found across a broad and rapidly expanding swath of the globe where they exploit human beings in two primary ways: i) specializing on humans for blood, which they use to develop eggs and ii) laying eggs in small bodies of fresh water associated with human settlement, such as drinking water containers, tires, or abandoned structures. Ae. aegypti larvae die in brackish water above ~10% seawater and adult females avoid ovipositing in these salinities. By contrast, Aedes togoi are not found in urban environments and breed in saline and brackish rockpools along the coast of western North America and Asia, with larvae able to tolerate salinities ranging from freshwater to 300% seawater. Little is known about how Ae. togoi select oviposition sites and, despite variation in life history traits and spread from the tropics to the subarctic, their range remains restricted to the coast. We propose to explore the basis of contrasting oviposition strategies, larval physiology, and habitat utilization flexibility across Ae. aegypti and Ae. togoi mosquitoes, with the following specific objectives: Objective 1: Determine the behavioural strategies guiding oviposition preference in Ae. aegypti and Ae. togoi using quantitative behavioural analysis and artificial selection Objective 2: Develop a comparative genomics approach for salt- and fresh-water breeding mosquitoes using de novo genome assembly and transcriptomics Objective 3: Identify causal molecular mechanisms and neural circuits underlying shifting oviposition preference using CRISPR/Cas9 to introduce novel alleles and elucidate circuit anatomy and function This research program will shed light on genetic and behavioural adaptations underlying habitat exploitation in mosquitoes by coupling a comparative approach with targeted genetic manipulation. Understanding how insects' nervous systems adapt and allow for exploitation of novel ecological niches is critical to predicting and pre-empting range increase of agricultural pest species and vectors of human and animal pathogens in a rapidly changing world.