Olfactory receptors and neurons regulating odor-guided behaviors in mosquitoes

项目摘要/摘要 冈比亚按蚊，作为导致疟疾的疟原虫寄生虫的昆虫载体， 导致了去年超过45万人的死亡幸运的是，蚊子有一个弱点 我们的研究旨在利用。蚊子利用它们的嗅觉来寻找宿主 行为。这表明，针对蚊子的嗅觉可能会导致有效的措施， 防止咬伤和疾病传播。事实上，空间驱避剂是挥发性气味剂， 扰乱宿主寻找行为，阻止蚊子靠近。它们广泛用于 发达国家作为个人保护措施，但由于成本高，全球采用有限， 不必要的副作用（如皮肤刺激），或需要使用高浓度， 有效鉴定新的、更易处理的驱避剂的一个主要限制是缺乏 了解空间驱避剂如何通过影响蚊子的嗅觉来促进排斥。 这主要是由于将驱蚊剂和其他气味剂与一种具有挑战性的 嗅觉神经元功能的多样性。我们将QF2/QUAS遗传二元系统引入到 按蚊克服了以前的技术障碍，现在使我们能够直接可视化 活体蚊子的嗅觉神经元对驱蚊剂和人体气味的反应。使用 钙成像、单感器电生理记录和RNA-seq沿着 我们将用我们建立的新的遗传技术来检验以下假设：（1）空间蚊子 驱避剂通过掩蔽、激活或扰乱嗅觉神经元的活性而起作用。我们将 检查活体冈比亚按蚊嗅觉神经元的活动模式， 在存在和不存在人类气味的情况下，由20种常用的驱蚊剂刺激。 此外，我们将确定嗅觉神经元表达的气味受体，这些受体表现出改变的嗅觉神经元的功能。 对每种驱避剂的反应模式。使用遗传方法的组合（旨在 调节目标嗅觉神经元的功能）和行为测定，我们将测试 空间驱避剂通过改变嗅觉系统促进驱避行为假说 发信号。我们将通过实验确定哪些嗅觉神经元和哪些类型的嗅觉神经元 神经元活动变化对于驱动驱避行为是必要的和/或足够的。的 拟议的研究是重要的，因为我们将获得新的机制的见解，蚊子如何 驱蚊剂的目标蚊子的嗅觉，使发展的基本原理生物为基础的 战略，以确定新的驱虫剂，更便宜，更安全，更有效地在全球范围内使用 防止疾病传播

Project Abstract/Summary Anopheles gambiae mosquitoes, as the insect vector for the Plasmodium parasite that causes malaria, were responsible for the deaths of >450,000 people last year. Fortunately, mosquitoes have a weakness that our research aims to exploit. Mosquitoes use their sense of smell for most human host-seeking behaviors. This suggests that targeting a mosquito's sense of smell could lead to effective measures that prevent bites and the spread of diseases. Indeed, spatial repellents are volatile odorants that effectively disrupt host-seeking behaviors and keep mosquitoes from approaching. They have widespread use in developed nations as personal protective measures, but global adoption is limited due to high costs, unwanted side-effects (such as skin irritation), or the need to use high-concentrations to remain effective. A major limitation to the identification of new, more tractable, repellents is a lack of understanding of how spatial repellents promote repulsion by impacting the mosquito's sense of smell. This is primarily due to challenging technical hurdles needed to link repellent and other odorants to a variety of olfactory neuron functions. Our introduction of the QF2/QUAS genetic binary system into Anopheles mosquitoes overcomes previous technical barriers, and now enables us to directly visualize the response of olfactory neurons, in living mosquitoes, to repellents and human body odors. Using a combination of calcium imaging, single sensillum electrophysiological recordings, and RNA-seq along with our established and novel genetic techniques, we will test the hypothesis that (1) spatial mosquito repellents function by masking, activating, or scrambling the activity of olfactory neurons. We will examine the activity patterns of olfactory neurons in living Anopheles gambiae mosquitoes when stimulated by 20 commonly used mosquito repellents in the presence and absence of human odorants. In addition, we will identify the odorant receptors expressed by olfactory neurons exhibiting altered activity patterns in response to each repellent. Using a combination of genetic approaches (aimed at modulating the function of targeted olfactory neurons) and behavioral assays, we will test the hypothesis that (2) spatial repellents promote repellent behaviors by altering olfactory system signaling. We will experimentally determine which olfactory neurons and what types of olfactory neuron activity changes are either necessary and/or sufficient to drive repellent behaviors. The proposed studies are significant because we will gain new mechanistic insights into how mosquito repellents target the mosquito's sense of smell and enable the development of rationale biology-based strategies to identify new repellents that are cheaper, safer, and more effective for use on a global scale to prevent the spread of disease.