Subcellular organization of Adhesion G-Protein Coupled Receptor (aGPCR) signalling.

粘附 G 蛋白偶联受体 (aGPCR) 信号传导的亚细胞组织。

• 批准号: RGPIN-2019-06166
• 负责人: Ramachandran, Rithwik
• 金额: $ 2.33万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=715952
• 关键词: Subcellular; organization; Adhesion; Protein; Coupled

The long-term objectives of my research program are to understand G-protein coupled receptor function. G-protein-coupled receptors (GPCRs) sense and traduce signals from numerous effector molecules and play an essential role in coordinating the ability of cells to rapidly respond to its environment. Specifically, my research is focused on understanding function of non-canonically activated G-protein coupled receptors (GPCRs). This proposal will focus on the Adhesion G-protein-coupled Receptor-G1 (ADGRG1; also known as GPR56). ADGRG1 is a member of the autocatalytically activated Adhesion Family of GPCRs. ADGRG1 undergoes an auto-catalytic event at a site called the GPCR proteolysis site (GPS), that results in the cell surface expression of a heterodimer consisting of 2 chains, a large extracellular N-terminal fragment (ADGRG1-NT) and a membrane-bound C-terminal fragment (ADGRG1-CT) which remain associated and non-covalently linked. It is believed that the ADGRG-NT is removed from ADGRG-CT through binding to extracellular matrix components and shear force resulting in ADGRG1-CT disinhibition, release and engagement of a tethered ligand and receptor signalling through G--proteins and --arrestin. The unique proteolytic mode of activation for ADGRG1 results in irreversible activation and these receptors are often described as “one and done” GPCRs. This is in contrast to the reversible binding of a soluble hormone that activates most well studies GPCRs such as the 2--adrenergic receptor (2-AR) or the angiotensin II receptor type 1 (AT1) that are frequently recycled back to the cell surface following internalization and dissociation of the ligand from the receptor. It follows that adhesion GPCRs might engage intracellular sorting mechanisms and compartmentalized signalling that are distinct from those for soluble hormone binding GPCRs. Overarching hypothesis: ADGRG1 engages intracellular vesicular trafficking and signalling pathways that are distinct from other hormone activated GPCRs such as 2-AR and AT1 as a result of irreversible auto-catalytic activation. In order to understand ADGRG1 signalling and trafficking, in the short-term, we will: Aim 1. Define ADGRG1 C-terminal tail amino acid sequences regulating interaction with the --arrestins. Aim 2. Define the vesicular trafficking route for internalization of ADGRG1 and the vesicular trafficking route for de-novo synthesized receptor trafficking to the cell membrane. Aim 3. Define the cell surface and endosomal signalling repertoire for ADGRG1. Significance: These studies will address fundamental questions regarding the signaling and vesicular transport mechanisms of a non-canonically activated GPCR. Given the important physiological roles and unique mechanisms of activation of this class of receptors, it is likely that these studies will reveal the diversity of pathways and mechanisms regulating the signaling and endocytic fate of GPCRs.

我的长期目标是从众多的效力和发挥作用，并在协调细胞迅速响应的能力中的重要作用提案将集中于G蛋白偶联受体-G1（ADGRG1；也称为GPR56）。 ADGRG1在一个名为GPCR蛋白质（GPS）ER的地点进行自动催化事件，该场所由2个链，一个大的外胞外N末端片段（ADGRG1-NT）和一个膜结合的C末端片段（ADGRG1-CT）组成与细胞外基质组件和剪切力保持相关的结合，并通过G-蛋白质和 - arrestin进行固定的配体和受体信号传导。 ADGRG1的独特蛋白水解导致不转化和Tepten被描述为“一个和DONE” CR，这与可溶性激素的可逆性结合形成了鲜明的对比，该激素激活了2--肾上腺素能受体（2-ar）等大多数良好的研究GPCR或血管紧张素II受体1型（AT1）经常回收到与可溶性激素结合GPCR不同的信号传递后回到细胞表面。 总体假设：与其他激活的PCR（如2-AR和AT1）不同的细胞内运输和信号通路，这是由于不可逆的自动催化激活而导致的。 为了了解ADGRG1信号传导和贩运​​，在短期内，我们将： AIM1。定义ADGRG1 C末端尾巴氨基酸调节与 - arrestin的相互作用。 AIM 2。定义ADGRG1的囊泡贩运途径和De-Novo合成的TR的囊泡贩运途径。 AIM 3。为ADGRG1定义细胞表面和内体信号传导rebertertoire。 显着性：Activa TED GPCR的信号传导和囊泡转运机制的标记揭示了调节GPCR信号传导和内吞命运的途径的多样性。