Regulation of G protein-coupled receptor signaling and trafficking

G 蛋白偶联受体信号传导和运输的调节

• 批准号: 10214632
• 负责人: Jeffrey L Benovic
• 金额: $ 50.7万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10214632
• 关键词: Address; Agonist; Arrestins; Binding; Biochemical; Cells; Complex; Development; Disease; Endocytosis; Environment; G Protein-Coupled Receptor Signaling; G protein coupled receptor kinase; G-Protein-Coupled Receptors; GRK5 gene; GTP-Binding Protein alpha Subunits, Gs; GTP-Binding Proteins; Heterotrimeric GTP-Binding Proteins; Hot Spot; Laboratories; Ligands; Mediating; Molecular Conformation; Molecular Structure; Molecular and Cellular Biology; Pharmaceutical Preparations; Phosphotransferases; Play; Process; Regulation; Research; Role; Signal Transduction; Structure; Therapeutic; Time; X-Ray Crystallography; beta-2 Adrenergic Receptors; beta-arrestin; biophysical analysis; desensitization; insight; receptor; receptor function; residence; trafficking

G protein-coupled receptors (GPCRs) play an essential role in coordinating the ability of cells to rapidly respond to their environment. Agonist binding to a GPCR promotes initial activation of heterotrimeric G proteins, which mediates downstream signaling. Agonist-occupied GPCRs then interact with GPCR kinases (GRKs), which specifically phosphorylate the receptor, and arrestins, which bind to GRK-phosphorylated receptors and function in GPCR desensitization, endocytosis, and signaling. A central question that drives current GPCR research involves understanding the dynamics and structures of GPCR interactions with G proteins, GRKs and arrestins. My laboratory is currently using a variety of strategies including X-ray crystallography, biochemical and biophysical analysis, and molecular and cellular biology to better understand the dynamics of GPCR regulation by GRKs and arrestins and the potential role of these processes in disease. In this application, we propose to address four questions that are central to understanding the mechanisms involved in GRK and arrestin regulation of GPCR signaling and trafficking. Can we obtain structural and dynamic insight on a GPCR/GRK complex? While we currently know little about the critical regions that mediate GRK interaction with GPCRs or how this interaction ultimately regulates GRK activation, our preliminary studies reveal three binding “hot spots” between the β2-adrenergic receptor (β2AR) and GRK5 and suggest large conformational changes in GRK5 upon binding to the receptor. How does β-arrestin interact with the β2-adrenergic receptor and β2-adaptin? β-arrestins play a central role in regulating GPCR signaling and trafficking so further understanding these interactions has important implications. Moreover, structural differences in the receptor when bound to its major downstream targets should provide insight on candidate regions to target in order to selectively enhance or disrupt specific interactions. Do α-arrestins play a broad role in regulating GPCR trafficking and signaling? We have found that the α-arrestin ARRDC3 functions as a switch to modulate the endosomal residence time and subsequent intracellular signaling of the β2AR. We will perform structure/function analysis of ARRDC3 interaction with the β2AR and assess whether ARRDCs have a broad role in regulating GPCR function. What is the molecular and structural basis of biased agonism? While it is evident that biased signaling through a number of GPCRs may ultimately prove to be of significant therapeutic value, literally nothing is known about the structural and mechanistic basis by which ligands can bias GPCR signaling. Overall, a more detailed understanding into these questions has tremendous implications for the development of more effective drugs to treat a wide variety of diseases.

G蛋白偶联受体（GPCR）在协调细胞的能力中起着至关重要的作用 回应他们的环境。激动剂与GPCR结合促进异三聚体G的初始激活 蛋白质，介导下游信号传导。激动剂占用的GPCR随后与GPCR激酶相互作用 （grks），特异性地磷酸化接收器和逮捕蛋白，该蛋白与GRK磷酸化结合 GPCR脱敏，内吞作用和信号传导中的受体和功能。驱动的主要问题 当前的GPCR研究涉及了解GPCR相互作用与G的动态和结构 蛋白质，GRK和逮捕蛋白。我的实验室目前正在使用包括X射线在内的各种策略 晶体学，生化和生物物理分析以及分子和细胞生物学，以更好地了解 GPCR调节的动力学是GRK和逮捕蛋白的动力学以及这些过程在疾病中的潜在作用。 在此应用程序中，我们建议解决四个对理解机制核心的问题 参与GPCR信号和贩运的GRK和逮捕法规。我们可以获得结构和 GPCR/GRK复合物的动态见解？虽然目前我们对关键地区一无所知 介导与GPCR的GRK相互作用，或这种相互作用最终如何调节GRK激活，我们 初步研究揭示了β2-肾上腺素受体（β2AR）和GRK5和GRK5和 建议在与接收器结合后GRK5中的巨大构象变化。 β-arrestin如何与 β2-肾上腺素受体和β2-适应素？ β-arrestin在调节GPCR信号和 贩运因此进一步了解这些相互作用具有重要的含义。而且，结构 当接收器绑定到其主要下游目标时，接收器的差异应提供有关候选人的见解 目标区域以选择性增强或破坏特定的相互作用。做α-arrestin的发挥作用 控制GPCR贩运和信号传导中的作用？我们发现α-arrestin arrdc3充当 切换以调节β2AR的内体停留时间和随后的细胞内信号传导。我们将 对ARRDC3与β2AR的相互作用进行结构/功能分析，并评估ARRDC是否具有 在调节GPCR功能中的广泛作用。偏见激动剂的分子和结构基础是什么？同时 有证据表明，通过许多GPCR进行偏见的信号传导最终可能被证明具有重要意义 治疗价值，从字面上看，配体可以的结构和机械基础一无所知 偏置GPCR信号。总体而言，对这些问题的更详细的理解有很大的理解 对开发更有效的药物的影响，以治疗多种疾病。