Functional and Mechanistic Dissection of GPCR Endosomal Signaling Dynamics

摘要 G蛋白偶联受体（GPCRs）是最大的一类药物靶点，也是重要的信号转导途径 翻译细胞外刺激以调节人体生理的蛋白质。因此，了解气相化学还原 信号级联将提供深入了解这些复杂的生理机制的分子机制， 过程，它们在疾病中的扰动，并告知我们设计更有效治疗方法的能力。近几 多年来，我的实验室和其他实验室已经做出了一个改变范式的发现，即GPCR可以在药物作用后被激活， 诱导从质膜到内体隔室的内化。然而，一个重要的 仍然未探索的变量是GPCR内体cAMP活性的时间动态如何影响 下行信号。在目前的建议中，我将剖析GPCR激活持续时间的影响， 内体对下游信号传导的影响，鉴定调节受体时空的新型蛋白质复合物 信号动力学，并将这些知识应用到一个生理相关的系统-海马神经元。通过 结合功能基因组学、蛋白质组学和光遗传学，该提案旨在提供一个全面的 了解内体中GPCR信号传导的时间动态如何调节生物学功能。 这项工作对于理解GPCR信号转导机制和识别新的信号转导机制是必不可少的 途径，为药物治疗提供新的靶点。

Abstract G protein-coupled receptors (GPCRs), which compose the largest class of drug targets, are critical signaling proteins that translate extracellular stimuli to mediate human physiology. As such, understanding GPCR signaling cascades will provide insight into the molecular mechanisms underlying these complex physiological processes, their perturbation in disease, and inform our ability to design more efficient therapeutics. In recent years, my lab and others have made a paradigm-shifting discovery that GPCRs can be activated after drug- induced internalization from the plasma membrane into endosomal compartments. However, one essential variable that remains unexplored is how the temporal dynamics of GPCR endosomal cAMP activity impact downstream signaling. In the current proposal, I will dissect the influence of the duration of GPCR activation in endosomes on downstream signaling, identify novel protein complexes that regulate receptor spatiotemporal signaling dynamics, and apply this knowledge to a physiologically relevant system—hippocampal neurons. By combining functional genomics, proteomics, and optogenetics, this proposal aims to provide a comprehensive understanding of how the temporal dynamics of GPCR signaling in endosomes regulates biological functions. This work is essential to comprehending the mechanisms of GPCR signaling and identifying novel signaling pathways, providing new targets for pharmacologic therapies.