Dynamics Of Ligand Gated Ion Channels

配体门控离子通道的动力学

• 批准号: 10570200
• 负责人: Vasanthi Jayaraman
• 金额: $ 67.78万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10570200
• 关键词: Agonist; Binding; Biochemical; Central Nervous System; Characteristics; Classification; Cognition; Color; Computing Methodologies; Data; Electrophysiology (science); Fluorescence; Glutamate Receptor; Goals; Image; Investigation; Ion Channel Gating; Ions; Isoxazoles; Kainic Acid Receptors; Laboratories; Learning; Ligands; Mediating; Mediator; Memory; Methods; Movement; N-Methylaspartate; Parkinson Disease; Physiological; Physiological Processes; Property; Propionates; Protein Subunits; Proteins; Role; Seizures; Stroke; Structure; Synapses; Synaptic Transmission; conformational conversion; delta receptors; dimer; kainate; nervous system disorder; protein complex; receptor; receptor function; single molecule; single-molecule FRET

PROJECT SUMMARY/ABSTRACT Glutamate receptors mediate the spread of excitation in the mammalian central nervous system, and ultimately control physiological functions such as movement and cognition. They are classified into four subfamilies: N-methyl-D-aspartate (NMDA), -amino-5-methyl-3-hydroxy-4-isoxazole propionate (AMPA), kainate, and delta receptors. All four subtypes are topologically similar, comprising four protein subunits held together as a dimer-of-dimers. However, their gating characteristics and mechanisms are unique, reflecting distinct roles in synaptic transmission. The goal of my laboratory is to understand the mechanisms that underlie the functional fine-tuning of each of these subtypes. Using a multipronged approach that combines biochemical, electrophysiological, fluorescence, and computational methods, we have already identified conformational transitions that are critical for mediating activation and inhibition of AMPA and NMDA glutamate receptors. However, a direct understanding of how such structural changes in one part of the protein control changes in other parts, and how they dictate functional properties, remains unknown. We propose to develop and use multicolor single-molecule fluorescence resonance energy transfer (FRET) to draw structure–function correlations between different segments of each glutamate receptor subtype. We will also focus our efforts on understanding the less well-studied kainate and delta subtypes. Specifically, we will investigate the mechanisms underlying activation and modulation of an abundant form of the kainate receptor by agonists, ions, and auxiliary proteins. In addition, we have preliminary data showing that delta receptor function is dependent on connections with trans-synaptic protein complexes, therefore we will study the structure and function of delta receptors in the context of synaptic binding partners. Together, these investigations will place our fundamental single-molecule investigations in a physiological context, and eventually allow us to understand functional differences between synaptic and non-synaptic glutamate receptors.

项目摘要/摘要 谷氨酸受体介导了哺乳动物中枢神经系统中兴奋的传播，并介导 最终控制生理功能，例如运动和认知。他们分为四个 亚家族：N-甲基-D-天冬氨酸（NMDA），-AMINO-5-甲基-3-羟基-4-甲氧唑丙酸酯（AMPA），AMPA（AMPA）， 海藻酸盐和三角洲受体。所有四个亚型在拓扑上都是相似的，完成了四个持有的蛋白质亚基 一起作为二聚体。但是，它们的门控特征和机制是独特的，反映了 突触传播中的不同作用。我的实验室的目的是了解基于的机制 每个亚型的功能微调。使用结合生化的多收益方法 电生理，荧光和计算方法，我们已经确定了构象 对于介导AMPA和NMDA谷氨酸受体的激活和抑制至关重要的过渡。 但是，直接了解蛋白质控制中一部分的这种结构变化如何变化 其他部分以及它们如何决定功能性能，仍然未知。我们建议开发和使用 多色单分子荧光共振能量转移（FRET）绘制结构 - 功能 每个谷氨酸受体亚型的不同段之间的相关性。我们还将集中精力 了解较少研究的海谷和三角洲子类型。具体而言，我们将研究机制 激动剂，离子和辅助的基础激活和调制大量的海藻酸盐接收器 蛋白质。此外，我们还有初步数据，显示Delta接收器功能取决于连接 与反式突触蛋白复合物一起，我们将研究三角体受体的结构和功能 突触结合伙伴的背景。这些调查将加在一起我们的基本单分子 在物理背景下进行调查，有时使我们能够理解功能差异 突触和非突触谷氨酸受体。