The Neuropeptide Control of Mosquito Host-Seeking Behavior

描述（由申请人提供）：埃及伊蚊是几种人类疾病的主要媒介，包括登革热，每年产生约5000万例病例，使25亿人处于危险之中（17）。对抗蚊媒疾病的新策略对A。埃及伊蚊以及其他蚊子如疟疾媒介冈比亚按蚊。我们的目标是发现新的方法来干扰蚊子定位人类宿主的能力。然而，宿主寻找及其调节的机制基础仍然不完全清楚。虽然已知蚊子需要人类气味线索来定位人类宿主，但关键气味组分和相关嗅觉受体尚未确定（12，23）。吸血后三天内，蚊子寻找宿主的行为会受到抑制。这种对进食行为的抑制部分是由神经肽头肽-I的释放引发的，但这种肽改变蚊子行为的机制及其信号受体尚不清楚（4）。头肽-I抑制宿主寻找行为的一种可能机制是调节蚊子闻到人类宿主的能力。为了研究这一假设，我们建议通过对目前未知的头肽-I受体进行去激活和定位来识别头肽-I反应神经元。使用基于细胞的钙成像屏幕，我们已经确定了G蛋白偶联受体NPY样受体-1（NPYLR 1）作为候选头肽-I受体。支持性数据显示，当注射到非血液喂养的雌性中时，多种NPYLR 1激动剂能够抑制宿主寻找行为。为了研究NPYLR 1是否是头部肽-I抑制所必需的，我们正在使用最近开创性的锌指核酸酶靶向诱变来产生NPYLR 1无效突变蚊子。我们预测，这些突变体将不再失去对人类气味线索的反应后，血液餐。为了定位头部肽-I响应NPYLR 1神经元，我们将使用定制的NPYLR 1抗体并创建荧光标记NPYLR 1表达细胞的转基因蚊子。这些信息将阐明头部肽-I抑制的神经机制，并可能形成控制蚊子宿主寻找行为的新策略的基础。

DESCRIPTION (provided by applicant): Aedes aegypti mosquitoes are the principal vectors for several human diseases including Dengue Fever, which generates ~50 million cases per year and places 2.5 billion people at risk (17). Novel strategies to combat mosquito-borne diseases are in high demand for A. aegypti as well as other mosquitoes such as the malarial vector Anopheles gambiae. Our goal is to discover new ways to interfere with the mosquito's ability to locate a human host for a blood meal. However, the mechanistic basis of host-seeking and its regulation remains incompletely understood. Although it is known that mosquitoes require human odor cues to locate a human host, the critical odor components and associated olfactory receptors have not been identified (12, 23). Mosquito host-seeking behavior is inhibited for three days following a blood meal. This suppression of feeding behavior is initiated in part by the release of the neuropeptide Head Peptide-I, but the mechanism by which this peptide alters mosquito behavior and the receptor through which it signals is unknown (4). One possible mechanism by which Head Peptide-I may inhibit host-seeking behavior is to modulate the mosquito's ability to smell a human host. To investigate this hypothesis, we propose to identify the Head Peptide-I responsive neurons by de-orphanizing and localizing the currently unknown Head Peptide-I receptor. Using a cell-based calcium-imaging screen, we have identified the G-protein coupled receptor NPY-Like Receptor-1 (NPYLR1) as a candidate Head Peptide-I receptor. Supporting data reveals that multiple NPYLR1 agonists are capable of inhibiting host-seeking behavior when injected into non-bloodfed females. To investigate whether NPYLR1 is required for Head Peptide-I inhibition, we are using recently pioneered targeted mutagenesis with zinc-finger nucleases to create NPYLR1 null-mutant mosquitoes. We predict that these mutants will no longer lose responsiveness to human odor cues after a blood meal. To localize Head Peptide-I responsive NPYLR1 neurons, we will use a custom NPYLR1 antibody and create transgenic mosquitoes that fluorescently mark NPYLR1 expressing cells. This information will clarify the neural mechanism of Head Peptide-I inhibition, and could form the basis of novel strategies to control mosquito host-seeking behavior.