Determinants of the Cannabinoid Receptor Life Cycle

大麻素受体生命周期的决定因素

• 批准号: 7500661
• 负责人: DEBRA A KENDALL
• 金额: $ 29.81万
• 依托单位: UNIVERSITY OF CONNECTICUT STORRS
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-25 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7500661
• 关键词: Absence of pain sensation; Activation Analysis; Address; Agonist; Alcohol abuse; Analgesics; Animal Model; Antiemetics; Area; Arrestin; Arrestins; Attenuated; Binding; Biochemical; Biological Assay; Bronchoconstriction; Cannabis sativa plant; Cell membrane; Cell surface; Coupling; Cultured Cells; Cysteine; Desire for food; Differentiation and Growth; Eating Disorders; Elements; Endoplasmic Reticulum; Equilibrium; Exhibits; G-Protein-Coupled Receptors; Goals; Helix (Snails); Hippocampus (Brain); Human; Laboratories; Life Cycle Stages; Ligand Binding; Ligands; Maps; Membrane; Membrane Proteins; Methods; Modeling; Molecular; Multiple Sclerosis; Mutagenesis; Nausea; Neuraxis; Neurons; Numbers; Obsessive Behavior; Peptides; Phosphorylation; Population; Preparation; Process; Property; Proteins; Receptor Activation; Relative (related person); Research; Research Activity; Rest; Role; SR 141716A; Signal Transduction; Staging; Structure; Study models; Surface; Tail; Tetrahydrocannabinol; Therapeutic; Therapeutic Agents; Time; Transmembrane Domain; Work; base; cannabinoid receptor; cigarette smoking; desensitization; ear helix; extracellular; functional group; membrane assembly; mutant; novel; receptor; response; tool; trafficking

DESCRIPTION (provided by applicant): The human cannabinoid receptor one (CB1) binds ?9-tetrahydrocannabinol, the psychoactive component of Cannabis sativa L., and other cannabimimetic compounds. It is a G-protein coupled receptor (GPCR) that is associated with the central nervous system and exerts its effects primarily via coupling to Gi/Go proteins. The pharmacological effects of CB1 agonists include analgesia, inhibition of nausea, appetite stimulation, antiemetic activity and bronchial dilation while inverse agonists attenuate excessive eating disorders. Any therapeutic strategy targeting CB1 will require that we have a firm understanding of the structural features of the receptor that impact key points in its life cycle: ER integration and cell surface expression, receptor activation, and desensitization and internalization. In Aim 1, we will examine the basis for the weak ER translocation of the CB1 amino terminus (N-tail). The structure of the N-terminus will be determined and accessory proteins and their recognition motifs in the N- and C-terminus will be identified. The role of these motifs in cellular localization including sematodendritic and axonal membrane surface localization in neurons will be examined. In Aim 2, we will build on our identification of structural elements of the receptor critical for distinguishing agonist and inverse agonist interactions and fully map the key contact points in the TM domain and the extracellular region of CB1 that are involved. We will define residues critical for poising the ligand- independent equilibrium of CB1 atypically toward activation and those responsible for the interconversion of this intermediate receptor state to the resting and activated forms of the receptor. In Aim 3, we will take advantage of novel receptor mutants that model different structural states of the receptor to examine linkages between receptor activation, desensitization, and cellular localization. Mutants that model the inactive and active forms of CB1 will provide tools for analyzing the consequences of prolonged treatment with inverse agonists and agonists. We will utilize our expertise in developing structural analyses and binding assays with purified components to examine the molecular basis of these processes with emphasis on the carboxyl terminus (C-tail) of the receptor. In the course of this work we will identify determinants that enhance the cell surface expression of CB1 and strategies for the large-scale preparation of domains of the receptor, and their structural analysis, which could be applied to structural studies of other GPCRs and membrane proteins in general. RELEVANCE: The cannabinoid receptor one (CB1) is a G-protein coupled receptor that is associated with the central nervous system. Research activities that have focused on the role of CB1 in signal transduction have underscored its enormous potential as a target for therapeutic agents. The goal of this project is to understand the structural features that influence key stages in the life cycle of CB1 including cell surface expression, receptor activation, and internalization and ultimately impact its cell surface exposure so that it will be accessible for therapeutic strategies.

描述（由申请人提供）：人大麻素受体一（CB1）结合α9-四氢大麻酚、大麻的精神活性成分和其他大麻模拟化合物。它是一种 G 蛋白偶联受体 (GPCR)，与中枢神经系统相关，主要通过与 Gi/Go 蛋白偶联发挥作用。 CB1激动剂的药理作用包括镇痛、抑制恶心、刺激食欲、止吐和扩张支气管，而反向激动剂则可减轻过度饮食失调。任何针对 CB1 的治疗策略都需要我们对影响其生命周期关键点的受体结构特征有深​​入的了解：ER 整合和细胞表面表达、受体激活、脱敏和内化。在目标 1 中，我们将检查 CB1 氨基末端（N 尾）弱 ER 易位的基础。将确定 N 末端的结构，并鉴定 N 末端和 C 末端的辅助蛋白及其识别基序。将检查这些基序在细胞定位中的作用，包括神经元中的细胞树突和轴突膜表面定位。在目标 2 中，我们将基于对区分激动剂和反向激动剂相互作用至关重要的受体结构元件的识别，并全面绘制 TM 结构域和所涉及的 CB1 细胞外区域中的关键接触点。我们将定义对于使 CB1 的配体独立平衡非典型地朝向激活至关重要的残基，以及负责该中间受体状态向受体的静止和激活形式相互转化的残基。在目标 3 中，我们将利用新型受体突变体来模拟受体的不同结构状态，以检查受体激活、脱敏和细胞定位之间的联系。模拟 CB1 的非活性和活性形式的突变体将为分析反向激动剂和激动剂长期治疗的后果提供工具。我们将利用我们在开发结构分析和纯化成分结合测定方面的专业知识来检查这些过程的分子基础，重点是受体的羧基末端（C 尾）。在这项工作的过程中，我们将确定增强 CB1 细胞表面表达的决定因素以及大规模制备受体结构域的策略及其结构分析，这些可应用于其他 GPCR 和膜蛋白的结构研究。相关性：大麻素受体一 (CB1) 是一种与中枢神经系统相关的 G 蛋白偶联受体。专注于 CB1 在信号转导中的作用的研究活动强调了其作为治疗药物靶点的巨大潜力。该项目的目标是了解影响 CB1 生命周期关键阶段的结构特征，包括细胞表面表达、受体激活和内化，并最终影响其细胞表面暴露，以便可用于治疗策略。