REGULATION OF NEURONAL RECEPTORS

神经元受体的调节

• 批准号: 6393725
• 负责人: EUGENE M BARNES
• 金额: $ 24.06万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-08-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6393725
• 关键词: GABA receptor; animal genetic material tag; benzodiazepines; binding proteins; chick embryo; clathrin; developmental neurobiology; gamma aminobutyrate; gene induction /repression; inositol phosphates; intermolecular interaction; neurogenetics; neuronal transport; neurons; neuropharmacology; protease inhibitor; protein biosynthesis; protein structure function; protein transport; receptor binding; receptor expression; tissue /cell culture; ubiquitin

DESCRIPTION: GABAA receptors (GABAARs) are the major sites for fast synaptic inhibition in the brain. The long-term goal of this project is to understand the neuronal regulation of GABAAR density and subcellular distribution. The investigators have previously demonstrated that acute exposure of cortical neurons to GABA or benzodiazepine agonists induces the transfer of surface GABAARs into a labile intracellular pool. In order to examine the underlying mechanisms and to evaluate their role in agonist-evoked GABAAR downregulation, three specific objectives are developed in this proposal. (1) To test the hypothesis that acute exposure of cortical neurons to benzodiazepines induces the sequestration of GABAAR subunits. Exoplasmic regions of GABAAR polypeptides on living neurons will be labeled with impermeant cleavable reagents. Following acute exposure to agonists, sequestered receptors will be recovered by stripping the surface label and doubly immunoprecipitating cell extracts with antibodies against GABAAR alpha1, beta2, and beta4 subunits. (2) To test the hypothesis that interactions of GABAARs with coated-pit proteins are evoked by agonists. The agonist-induced interactions of GABAAR subunits with inositol polyphosphate binding proteins as well as proteins identified by yeast two-hybrid screening will be examined by co-precipitation. (3) To test the hypothesis that GABAARs are degraded by distinct agonist-dependent and agonist-independent pathways. GABAAR subunits will be labeled internally by incorporation of 35S-Met/Cys and externally by impermeant non-cleavable reagents. The effect of agonists and protease inhibitors on the turnover rates will be determined. It is suggested that this project will provide new insights into pathways which modulate synaptic function. By means of these regulatory mechanisms, cell-cell communication and drug-cell interaction can produce persistent changes in neuronal excitability. Furthermore, these are likely to represent molecular mechanisms which establish tolerance and habituation to benzodiazepines, barbiturates, and alcohol.

描述：GABAA受体（GABAARS）是快速的主要网站 大脑突触抑制。 该项目的长期目标是 了解GABAAR密度和亚细胞的神经元调节 分配。 调查人员以前已经证明了急性 将皮质神经元暴露于GABA或苯二氮卓激动剂诱导 将表面加巴人转移到不稳定的细胞内池中。 为了 检查潜在机制并评估其在 激动剂诱发的Gabaar下调，三个具体目标是 在此提案中开发。 （1）检验急性暴露的假设 苯二氮卓类皮质神经元的诱导Gabaar的隔离 亚基。 Gabaar多肽在活神经元上的外质区域将 用不足的裂解试剂标记。 急性暴露 激动剂，隔离的受体将通过剥离表面回收 标记和双重免疫沉淀细胞提取物，抗体抗体 Gabaar alpha1，beta2和beta4亚基。 （2）检验以下假设 Gabaars与涂层灰蛋白的相互作用是由激动剂引起的。 激动剂诱导的Gabaar亚基与肌醇的相互作用 酵母鉴定的蛋白质以及蛋白质 将通过共归化检查两杂交筛选。 （3）测试 假设Gabaars被不同的激动剂依赖性和 不依赖激动剂的途径。 Gabaar亚基将在内部标记 掺入35-MET/CYS，外部由无渗透性不可融合 试剂。 激动剂和蛋白酶抑制剂对营业额的影响 费率将被确定。 建议该项目提供 对调节突触功能的途径的新见解。 通过 这些调节机制，细胞 - 细胞通信和药物细胞 相互作用可以产生神经元兴奋性的持续变化。 此外，这些可能代表分子机制 建立对苯二氮卓，巴比妥酸盐和习惯的耐受性和习惯 酒精。