Gating and Permeation in Ionotropic Glutamate Receptors

离子型谷氨酸受体的门控和渗透

基本信息

批准号：
10592327
负责人：
LONNIE P WOLLMUTH
金额：
$ 42.08万
依托单位：
STATE UNIVERSITY NEW YORK STONY BROOK
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10592327
关键词：
AMPA Receptors Acute Address Affect Agonist Alzheimer&apos s Disease Binding Biological Assay Brain Brain Diseases C-terminal Cell Death Cells Chemicals Chronic Clinic Communication Complement Coupling Cysteine Data Disease Electrophysiology (science)Elements Epilepsy Event Explosion Extracellular Domain Fluorescence Resonance Energy Transfer Free Energy Glutamate Receptor Glutamates Goals Human Inherited Ion Channel Ion Channel Gating Isomerism Kinetics Learning Ligand Binding Domain Link Measurement Mediating Membrane Molecular Mutation N-Methyl-D-Aspartate Receptors NMDA receptor A1 Nervous System Neurodevelopmental Disorder Neurotransmitters Outcome Pathway interactions Pharmaceutical Preparations Physiology Positioning Attribute Potassium Channel Property Proteins Publishing Resolution Role Schizophrenia Signal Transduction Societies Specificity Spermine Stroke Structure Synapses Synaptic Transmission Testing Transmembrane Domain autism spectrum disorder comparative crosslink de novo mutation disease-causing mutation epileptic encephalopathies excitotoxicity experimental study insertion/deletion mutation mind control molecular dynamics mutation assay nervous system disorder novel operation postsynaptic presynaptic receptor receptor function small molecule stargazin synaptic function

项目摘要

Our long-term goal is to address molecular determinants of brain disorders. Fast synaptic transmission in the brain is mediated by ion channels that are directly activated by a chemical neurotransmitter. NMDA and AMPA receptors are glutamate-gated ion channels that convert the presynaptic release of glutamate, the predominant excitatory neurotransmitter in the brain, into a postsynaptic signal. By defining the operation of NMDA and AMPA receptors, we will gain a better understanding of how they control brain function. We will also learn how to modulate their function with greater precision and specificity to help understand, and potentially treat, brain disroders such as schizophrenia, epilepsy, and the excitotoxicity associated with acute and chronic brain disorders. Our experiments will focus on a eukaryotic transmembrane segment, the M4 segment, which is positioned around the pore domain. Recent published and preliminary data from our lab has indicated that the M4 segments act in novel ways to regulate core synaptic functions of NMDA and AMPA receptors. Highlighting their significance is that inherited and de novo mutations in the M4 segments induce neurodevelopmental disorders and epileptic encephalopathies. Aim 1 will address the novel hypothesis that the unique kinetics of NMDA receptors at synapses are due to two kinetically distinct gates and that the M4 segments regulate these gates in a subunit-specific manner. We will address this hypothesis using cysteine cross-linking, rigorous single channel analysis, and molecular dynamic simulations. Aim 2 will address the hypothesis that the M4 segments in NMDA receptors are a major allosteric conduit coupling external domains to transmembrane and internal domains. Here, we will test this hypothesis by decoupling external domains from transmembrane and internal domains and assay this decoupling using electrophysiological and FRET based measurements. Aim 3 will address the hypothesis that the M4 segments in AMPA receptors carry out distinct functional roles including acting as a conduit for auxiliary proteins found at synapses. Here, we will compare functional properties between the M4 segments in NMDA and AMPA receptors using electrophysiological recordings and molecular dynamic simulations. Our experiments will delineate molecular features of NMDA and AMPA receptors that contribute to synaptic function. This information will aid in developing specific therapies to target these receptors in nervous system disorders.

我们的长期目标是解决脑疾病的分子决定因素。快速突触大脑中的传播是由直接通过化学物质激活的离子通道介导的神经递质。 NMDA和AMPA受体是谷氨酸门控的离子通道，可转换谷氨酸的突触前释放，谷氨酸是大脑中主要的兴奋性神经递质，突触后信号。通过定义NMDA和AMPA受体的操作，我们将获得更好的了解它们如何控制大脑功能。我们还将学习如何调节其功能具有更高的精确性和特异性，以帮助理解和治疗脑部疾病，例如精神分裂症，癫痫以及与急性和慢性脑疾病有关的兴奋性。我们的实验将集中于真核跨膜段，即M4段，位于孔域周围。我们实验室的最新发布和初步数据已指出 M4段以新颖的方式起作用NMDA和AMPA的核心突触功能受体。强调它们的意义是M4段中的遗传和从头突变诱导神经发育障碍和癫痫性脑病。 AIM 1将解决小说假设突触下NMDA受体的独特动力学是由于两个动力学上的不同门和M4段以亚基特异性方式调节这些门。我们将解决使用半胱氨酸交联，严格的单通道分析和分子动力学的假设模拟。 AIM 2将解决以下假设：NMDA受体中的M4片段是主要的变构导管将外部域耦合到跨膜和内部域。在这里，我们会的通过从跨膜和内部域将外部域和使用基于电生理和FRET的测量结果测定这种解耦。 AIM 3将解决 AMPA受体中的M4片段发挥不同的功能作用，包括充当突触中发现的辅助蛋白的导管。在这里，我们将比较功能使用电生理学的NMDA和AMPA受体的M4段之间的特性记录和分子动态模拟。我们的实验将描述 NMDA和AMPA受体有助于突触功能。这些信息将有助于开发特定的疗法来靶向这些受体在神经系统疾病中。