Function and regulation of heterotrimeric G proteins in ciliogenesis and pathobiology of neurodevelopmental disorders

项目总结 G蛋白偶联受体(GPCR)信号的许多成分，包括异源三聚体G(ABG) 蛋白质定位于初生纤毛，并调节其形态。虽然纤毛缺陷和G调节失调 蛋白质信号与神经发育障碍(NDDS)有关，G 蛋白质调节纤毛形态发生或纤毛Ga信号中断对NDDS的影响程度 在很大程度上仍然不为人知。这项提议的总体目标是定义分子机制， RIC-8--一种高度保守的不依赖于gpr的GA蛋白激活剂--塑造感官纤毛形态 神经元。这一应用的主要假设是RIC-8被动态地输送到感觉纤毛 并通过增强GA信号来控制纤毛的发生。这一假设将通过追求两个具体的 目标。在第一个目标下，体内蛋白质相互作用分析和基因组编辑方法将被用于 从力学上确定RIC-8-GAI/O轴在控制纤毛形态发生中的功能作用。对于 第二个目标是，一个由遗传、成像和体内蛋白质组学方法组成的协同方法将是 应用于识别RIC-8纤毛运输和感觉神经元功能的分子调节器。建议数 研究具有创新性，因为它使用了一种全面的方法来定义RIC-8的一种新的细胞功能- Gai/o信号在神经元发育中的作用。这项拟议的研究具有重要意义，因为它有望确定 研究纤毛RIC-8分子组成和功能的强大科学框架- 线虫和脊椎动物模型中的GAI/O信号网络(S)以及确定GA蛋白信号是如何改变的 可能导致神经发育障碍。

PROJECT SUMMARY Many components of G-protein-coupled receptor (GPCR) signaling including heterotrimeric G (abg) proteins localize to primary cilia and modulate their morphology. Although cilia defects and dysregulated G protein signaling are associated with neurodevelopmental disorders (NDDs), the mechanisms by which G proteins regulate cilia morphogenesis or the extent to which disruption of ciliary Ga signaling contributes to NDDs remain largely unknown. The overall objective for this proposal is to define the molecular mechanisms by which RIC-8 – a highly conserved GPCR-independent activator of Ga proteins – shapes cilia morphology in sensory neurons. The overarching hypothesis for this application is that RIC-8 is dynamically trafficked to sensory cilia and controls ciliogenesis by potentiating Ga signaling. This hypothesis will be tested by pursuing two specific aims. Under the first aim, in vivo protein interaction assays and genome editing approaches will be used to mechanistically define the functional role of the RIC-8-Gai/o axis in controlling cilia morphogenesis. For the second aim, a synergistic approach comprised of genetic, imaging and in vivo proteomic approaches will be applied to identify molecular regulators of RIC-8 ciliary transport and function in sensory neurons. The proposed research is innovative because it uses a comprehensive approach to define a novel cellular function of RIC-8- Gai/o signaling in neuronal development. The proposed research is significant because it is expected to establish a strong scientific framework for investigations into the molecular composition and functions of the ciliary RIC-8- Gai/o signaling network(s) in C. elegans and vertebrate models and to determine how altered Ga-protein signaling may contribute to neurodevelopmental disorders.