Mechanism of activation and modulation in human GABA(B) receptor

人 GABA(B) 受体的激活和调节机制

基本信息

批准号：
10224896
负责人：
QING R FAN
金额：
$ 42.18万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-09-01 至 2022-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10224896
关键词：
Address Adenylate Cyclase Affect Affinity Agonist Anxiety Baculoviruses Behavioral Binding Binding Proteins Biological Assay Brain Brain Diseases Cell Surface Receptors Cell surface Cells Communication Complex Coupling Cryoelectron Microscopy Crystallization Data Defect Development Disease Electron Microscopy Epilepsy Extracellular Domain Family G-Protein-Coupled Receptors GABA-B Receptor GTP-Binding Protein alpha Subunits, Gs GTP-Binding Proteins Goals Homo Human Insecta Kinetics Length Ligand Binding Ligands Light Measures Mediating Modeling Molecular Molecular Conformation Molecular Structure Mood Disorders Mutation Neurotransmitters Peptides Potassium Channel Property Proteins Receptor Activation Receptor Signaling Regulation Rest Side Signal Transduction Structural Models Structure Therapeutic Agents Transmembrane Domain X-Ray Crystallography addiction base brain behavior desensitization design dimer experimental study extracellular gamma-Aminobutyric Acid human disease innovation member molecular mass nanodisk nervous system disorder neurotransmission novel therapeutics radioligand receptor receptor function reconstitution scaffold spasticity synaptic inhibition

项目摘要

PROJECT SUMMARY The inhibitory neurotransmitter GABA produces slow and prolonged inhibition in the brain through activation of metabotropic GABAB receptors (GABABR). Defects in GABABR signaling have been implicated in various neurological and mood disorders including spasticity, epilepsy, addiction and anxiety. GABABR is a member of the class C G protein-coupled receptor (GPCR) family, which typically functions as a dimer and possesses large extracellular domains. Fundamental questions remain concerning the molecular mechanisms underlying activation and modulation of these class C receptors. The GABABR is a heterodimer of GABAB1 and GABAB2 subunits and is modulated by the potassium channel tetramerization domain-containing (KCTD) protein auxiliary subunits. In this proposal, we will develop structural models for full-length GABABR, its auxiliary subunits and their complexes with G- protein. Building on our structural models for both the extracellular and intracellular components of human GABABR, we propose to determine the structural diversity of GABABR auxiliary subunits KCTDs, and elucidate the interactions between KCTDs and G proteins (Aim 1), describe the molecular association between GABABR and KCTD, and determine its impact on GABABR signaling (Aim 2), and solve the structures of full-length GABABR in multiple functional states, characterizing the allosteric interaction between the GABABR and G proteins (Aim 3). We will use an innovative strategy of combining structural and functional analyses, including cryo-electron microscopy (EM) and nanodiscs. Together, these studies will advance our understanding of the molecular basis of GABA action in the brain, leading to the development of novel therapeutics for treating neurological diseases.

项目摘要抑制性神经递质GABA通过代谢性GABAB受体（GABABR）的激活。 Gababr信号的缺陷已经与各种神经和情绪障碍有关，包括痉挛，癫痫，成瘾和焦虑。 Gababr是C级蛋白偶联受体（GPCR）家族的成员，通常充当二聚体并具有大的细胞外域。仍然存在基本问题关于这些C类受体的激活和调节的分子机制。 Gababr是GABAB1和GABAB2亚基的异二聚体，由钾调节通道四聚体域（KCTD）蛋白辅助亚基。在此提案中，我们将开发全长Gababr，其辅助亚基及其与G-的复合物的结构模型蛋白质。建立在我们的结构模型的基础上，用于用于细胞外和细胞内组件人类Gababr，我们建议确定GABABR辅助亚基的结构多样性 KCTD并阐明KCTDS与G蛋白之间的相互作用（AIM 1），描述了分子 GABABR和KCTD之间的关联，并确定其对Gababr信号传导的影响（AIM 2）和在多个功能状态下解决全长GABABR的结构，表征变构性 GABABR和G蛋白之间的相互作用（AIM 3）。我们将使用一种创新的策略结合结构和功能分析，包括冷冻电子显微镜（EM）和纳米盘。这些研究将共同提高我们对GABA作用分子基础的理解大脑，导致开发用于治疗神经系统疾病的新型治疗剂。