Role of beta-arrestins in G protein-coupled receptor sorting and signaling

β-抑制蛋白在 G 蛋白偶联受体分选和信号转导中的作用

• 批准号: 8632561
• 负责人: Adriano Marchese
• 金额: $ 29.08万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-02-11 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8632561
• 关键词: ARRB1 gene; Address; Adult; Arrestin Beta 1; Arrestins; Binding; Biochemical; CXCR4 gene; Cell membrane; Complement; Complex; Coupled; Data; Development; Disease; Embryonic Development; Endocytosis; Endosomes; Fluorescence Microscopy; G Protein-Coupled Receptor Signaling; G protein coupled receptor kinase; G-Protein-Coupled Receptors; GTP-Binding Proteins; Goals; In Vitro; Knowledge; Lead; Link; Lysosomes; Mediating; Molecular; Molecular and Cellular Biology; Multivesicular Body; Nature; Pathogenesis; Pathway interactions; Physiological Processes; Play; Process; Proteins; Recruitment Activity; Research; Role; Series; Signal Transduction; Sorting - Cell Movement; Techniques; Testing; Time; Ubiquitin; Vesicle; arrestin 1; attenuation; base; beta-arrestin; body system; cell motility; cellular imaging; chemokine receptor; human disease; in vivo; innovation; insight; novel; prevent; programs; protein complex; public health relevance; receptor; receptor internalization; spatiotemporal; therapeutic target; trafficking; ubiquitin-protein ligase

Project Description GPCR signaling is essential for a wide variety of physiological processes. GPCR signaling can also play an active role in the pathogenesis of multiple diseases. GPCRs are normally tightly regulated so that signals are of the appropriate magnitude and duration and any perturbations in these regulatory processes can be deleterious. Typically, GPCR signaling is tightly regulated by G protein-coupled receptor kinases (GRKs) and ¿-arrestins. ¿-arrestins bind to GRK-phosphorylated GPCRs at the plasma membrane to terminate signaling by promoting G protein uncoupling and receptor endocytosis. The molecular mechanisms by which GRKs and ¿- arrestins regulate GPCR signaling remain poorly understood. The goal of this proposal is to elucidate the molecular mechanisms by which GRKs and ¿-arrestins govern GPCR signaling. Recently, we described a novel function for ¿-arrestins, as endosomal sorting molecules, whereby they function on endosomes to mediate sorting of GPCRs from endosomes to lysosomes, leading to receptor degradation and long-term attenuation of signaling. However, mechanistic insight into this new function is lacking. ¿-arrestin-1 mediates endosomal sorting of the chemokine receptor CXCR4, which also requires the action of the E3 ubiquitin ligase AIP4 and the ESCRT (endosomal sorting complex required for transport) machinery. How ¿-arrestin-1 functionally integrates with AIP4 and ESCRTs to mediate CXCR4 endosomal sorting remains to be determined. Based on our strong preliminary data we hypothesize that ¿-arrestin-1 regulates the ESCRT machinery to control CXCR4 endosomal trafficking and signaling. We propose the following two specific aims: Aim 1: To determine the molecular mechanisms by which ¿-arrestin-1 integrates with AIP4 and ESCRTs to control CXCR4 endosomal sorting. Aim 2: To determine the molecular mechanisms by which ESCRTs regulate CXCR4 signaling and function. We will utilize a comprehensive series of state-of-the-art biochemical, molecular and cellular biology and imaging approaches to complete these aims. We anticipate that new knowledge gained from this proposal will lead to the identification of new and innovative approaches to manipulate GPCR signaling to prevent and treat a variety of diseases.

项目描述 GPCR 信号传导对于多种生理过程至关重要。 GPCR 信号还可以发挥 在多种疾病的发病机制中发挥积极作用。 GPCR 通常受到严格监管，因此信号 适当的幅度和持续时间以及这些监管过程中的任何扰动都可以 有害的。通常，GPCR 信号传导受到 G 蛋白偶联受体激酶 (GRK) 的严格调控，并且 ¿-逮捕。 ¿-arrestins 与质膜上的 GRK 磷酸化 GPCR 结合，通过以下方式终止信号传导： 促进G蛋白解偶联和受体内吞作用。 GRKs 和 ¿- 的分子机制 抑制蛋白对 GPCR 信号传导的调节仍知之甚少。该提案的目标是阐明 GRK 和 ¿-arrestins 控制 GPCR 信号传导的分子机制。最近，我们描述了一个 ¿-arrestins 的新功能，作为内体分选分子，它们在内体上发挥作用 介导 GPCR 从内体到溶酶体的分类，导致受体降解和长期 信号衰减。然而，缺乏对这一新功能的机械洞察。 ¿-arrestin-1 介导 趋化因子受体 CXCR4 的内体分选，也需要 E3 泛素连接酶的作用 AIP4 和 ESCRT（运输所需的内体分选复合体）机器。如何 ¿-arrestin-1 与 AIP4 和 ESCRT 功能性整合以介导 CXCR4 内体分选仍有待研究 决定。根据我们强有力的初步数据，我们假设 ¿-arrestin-1 调节 ESRT 控制 CXCR4 内体运输和信号转导的机制。我们提出以下两个具体目标： 目标 1：确定 ¿-arrestin-1 与 AIP4 和 ESCRT 整合的分子机制 控制 CXCR4 内体分选。目标 2：确定 ESRT 调节的分子机制 CXCR4 信号传导和功能。我们将利用一系列全面的、最先进的生化、 分子和细胞生物学以及成像方法来完成这些目标。我们预计新的 从该提案中获得的知识将导致确定新的和创新的方法 操纵 GPCR 信号传导来预防和治疗多种疾病。