Ethanol Sensitivity of Native and Cloned NMDA Receptors

天然和克隆 NMDA 受体的乙醇敏感性

基本信息

批准号：
7865896
负责人：
JOHN J. WOODWARD
金额：
$ 9.4万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-07-15 至 2011-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7865896
关键词：
Acute Address Affect Alanine Alcohol abuse Alcohols Amino Acids Behavior Brain C-terminal Cells Chronic Complex Cyclic AMP-Dependent Protein Kinases Cysteine Cytoskeleton D Aspartate Electrophysiology (science)Ethanol Event Funding Future Gated Ion Channel Genetic Glutamates Goals Hippocampus (Brain)In Vitro Intrinsic factor Ion Channel Ions Knock-in Mouse Learning Ligands Lipids Measures Mediating Memory Modification Molecular Mus Mutagenesis Mutate Mutation N-Methyl-D-Aspartate Receptors N-Methylaspartate NR1 gene Neurons Peptides Phenylalanine Phosphoric Monoester Hydrolases Phosphorylation Phosphorylation Site Phosphotransferases Post-Translational Protein Processing Principal Investigator Process Protein Kinase Proteins Proto-Oncogene Proteins c-fyn Recombinants Resistance Scanning Site Slice Solutions Specificity Synapses Synaptic Transmission Synaptic plasticity Techniques Testing Transgenic Mice Transgenic Organisms Transmembrane Domain Up-Regulation Viral Withdrawal Work alcohol effect alcohol sensitivity base calmodulin-dependent protein kinase II design experience follow-up functional status in vivo inhibitor/antagonist molecular site mutant patch clamp physical property programs receptor receptor function receptor sensitivity research study

项目摘要

DESCRIPTION (provided by applicant): The major goals of this project are to elucidate the molecular sites and mechanisms of action of ethanol on the N-methyI-D-aspartate class of ion channels. NMDA receptors are a subtype of glutamate-activated ligand-gated ion channel and they are involved in excitatory synaptic transmission in the brain. They mediate several forms of synaptic plasticity that underlie learning and memory and inhibition of their function by pharmacological or genetic means disrupts these complex behaviors. Acutely, ethanol inhibits ion flux through NMDA receptors while chronic exposure of neurons to ethanol induces an up-regulation in the functional status of these receptors that is manifested by signs of CNS excitability during withdrawal. Identifying the factors that regulate the inhibition of NMDA receptors by ethanol is important as acute sensitivity to the intoxicating effects of ethanol appears to be an important predictor of future alcohol abuse. Previous work carried out during this project identified several factors that can regulate the magnitude of inhibition of NMDA receptors to ethanol. These included subunit composition and post-translational modifications including phosphorylation and cytoskeleton interactions. In addition, this project identified an amino acid in the NR1 subunit of the receptor (F639) that when mutated to alanine significantly reduced the inhibitory effects of ethanol on NMDA receptors containing any NR2 subunit. In this application, three specific hypotheses are proposed to further define the molecular mechanisms that regulate the ethanol sensitivity of NMDA receptors. Aim 1 will extend our mutagenesis studies to examine additional mutations at F639 and homologous NR2 sites as well as residues in other TM domains. Aim 2 will investigate the effects of C-terminal phosphorylation of NR1 and NR2 residues on ethanol inhibition of NMDA receptors. Aim 3 will express ethanol-insensitive receptors identified in Aims 1 and 2 in neurons in vitro and in vivo to address which effects of ethanol are mediated by inhibition of NMDA receptors.

描述（由申请人提供）：该项目的主要目标是阐明乙醇对 N-甲基-D-天冬氨酸类离子通道的分子位点和作用机制。 NMDA 受体是谷氨酸激活配体门控离子通道的一种亚型，它们参与大脑中的兴奋性突触传递。它们介导多种形式的突触可塑性，这些突触可塑性是学习和记忆的基础，通过药理学或遗传手段抑制其功能会破坏这些复杂的行为。乙醇会急性抑制通过 NMDA 受体的离子通量，而神经元长期暴露于乙醇会诱导这些受体功能状态的上调，这通过戒断期间中枢神经系统兴奋性的迹象来体现。确定调节乙醇抑制 NMDA 受体的因素非常重要，因为对乙醇中毒作用的急性敏感性似乎是未来酒精滥用的重要预测因素。该项目之前进行的工作确定了几个可以调节 NMDA 受体对乙醇抑制程度的因素。这些包括亚基组成和翻译后修饰，包括磷酸化和细胞骨架相互作用。此外，该项目还鉴定了受体 NR1 亚基 (F639) 中的一个氨基酸，当该氨基酸突变为丙氨酸时，可显着降低乙醇对含有任何 NR2 亚基的 NMDA 受体的抑制作用。在本申请中，提出了三个具体假设，以进一步定义调节 NMDA 受体乙醇敏感性的分子机制。目标 1 将扩展我们的诱变研究，以检查 F639 和同源 NR2 位点以及其他 TM 结构域中的残基的其他突变。目标 2 将研究 NR1 和 NR2 残基 C 端磷酸化对乙醇抑制 NMDA 受体的影响。目标 3 将在体外和体内神经元中表达目标 1 和 2 中鉴定的乙醇不敏感受体，以解决乙醇的哪些作用是通过抑制 NMDA 受体介导的。