Structure and mechanism of extrasynaptic GABAA receptors

项目总结： A型γ-氨基丁酸受体是一种五聚体配体门控离子通道 在中枢神经系统中大量存在。脑内主要抑制性神经递质GABA与 GABAA受体约占大脑中快速突触信号的30%。这些受体很重要 用于感觉和运动处理、中央自主神经控制和认知。虽然许多研究都是在 GABAA受体的结构和功能主要集中在突触的亚单位组装上， 在突触外发现了多种药理上重要的GABAA受体亚型。的目标是 这项建议是为了确定和验证突触外GABAA受体结合的高分辨率结构 与神经性疾病、麻醉、成瘾和药物滥用相关的不同药物类别。这些 受体被轻度醉人浓度的乙醇增强，对神经类固醇有很高的亲和力 是麻醉剂、镇痛剂和抗惊厥药物的靶标。在两个目标中，我建议优化 确定的异构体GABAA受体组件的表达和纯化条件，精制样品 为低温电子显微镜做准备，收集和处理单粒子低温电子显微镜数据集，并建立和 完善受体-药物复合体的原子模型。生理学的高分辨率结构信息 重要但研究不足的亚基组件，在与变构和正构配位配体的络合物中将广泛地 介绍配基识别和亚基组装的原理。 好了！

Project Summary: Type A γ-aminobutyric acid receptors (GABAA) are pentameric ligand-gated ion channels found abundantly in the central nervous system. The binding of GABA, the major brain inhibitory neurotransmitter, to GABAA receptors, accounts for ~30% of the fast synaptic signaling in the brain. These receptors are important for sensory and motor processing, central autonomic control, and cognition. While much of the research in GABAA receptor structure and function has focused on the subunit assemblies found at synapses, a tremendous diversity of pharmacologically important GABAA receptor subtypes are found outside of synapses. The goal of this proposal is to determine and validate high-resolution structures of extrasynaptic GABAA receptors bound to distinct drug classes of relevance to neurological disorders, anesthesia, addiction and drug abuse. These receptors are potentiated by mildly intoxicating concentrations of ethanol, have high affinity for neurosteroids and are targets of anesthetics, analgesics, and anticonvulsant drugs. In two Aims, I propose to optimize conditions for expression and purification of defined heteromeric GABAA receptor assemblies, refine sample preparation for cryo-electron microscopy, collect and process single particle cryo-EM datasets, and build and refine atomic models of receptor-drug complexes. High-resolution structural information for physiologically important but understudied subunit assemblies, in complex with allosteric and orthosteric-site ligands will broadly inform on principles of ligand recognition and subunit assembly. !