STRUCTURE AND FUNCTION OF NICOTINIC RECEPTORS

烟碱受体的结构和功能

基本信息

批准号：
6472795
负责人：
JOSE Antonio LASALDE-DOMINICCI
金额：
$ 11.03万
依托单位：
UNIVERSITY OF PUERTO RICO RIO PIEDRAS
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-07-01 至 2002-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6472795
关键词：
Torpedo Xenopus acetylcholine allosteric site anesthetics biomaterial interface interaction electrophysiology intermolecular interaction lipids membrane channels nicotinic receptors protein protein interaction protein structure function site directed mutagenesis tryptophan voltage /patch clamp

项目摘要

Description (Adapted from Application): The long-range goal of this research proposal is to combine electrophysiological, biochemical, biophysical and molecular biological techniques to gain insight into the structure and function of the nicotinic acetylcholine receptor (AChR) with special attention on protein-lipid interactions. The emphasis of this project is organized on three independent approaches: (1) The first approach is to extend ongoing site directed mutagenesis at lipid-exposed residues of the Torpedo AChR that have shown to affect the channel gating mechanism. The investigators propose to introduce additional amino acid replacements at the new hydrophobic allosteric position alpha-V425 position. These studies will further test the hypothesis that a number of allosteric sites at the lipid protein interface have a critical role on the AChR channel gating. The identification and functional characterization of these lipid-exposed allosteric sites will provide further insights into the structure-function relationships of the AChR. (2) The second approach proposes to introduce periodic tryptophan substitutions to cover all the positions along the M4 transmembrane domains for beta, gamma and delta subunits. A systematic analysis of a series of tryptophan substitutions will provide information of the physical location of helix-helix or subunit-subunit contacts that are critical for the functional oligomerization of the AChR. The positional location of possible constraint sites may identify additional aspects of the spatial organization of the M4 transmembrane domains in respect to the Ml and M3 domains as well as to structure-function relationships of the AChR. (3) The third approach is to use novel Torpedo M4 AChR mutations to examine the sensitivity of the lipid-protein interface to the action of various types of general anesthetics. The objectives of this project are to define the biochemical and biophysical interactions of these allosteric sites and to identify additional aspects of the spatial organization of the M4 transmembrane domains of the AChR.

描述（改编自应用程序）：本研究的长期目标建议将电生理学、生物化学、生物物理和分子生物学技术，深入了解结构和功能烟碱乙酰胆碱受体（AChR）的研究，特别关注蛋白质-脂质相互作用。该项目的重点分为三个独立方法：（1）第一种方法是扩展正在进行的站点对鱼雷 AChR 的脂质暴露残基进行定向诱变，显示出影响通道门控机制。调查人员建议在新的疏水变构处引入额外的氨基酸替代位置α-V425位置。这些研究将进一步检验假设脂蛋白界面上的许多变构位点具有在 AChR 通道门控中发挥关键作用。识别及功能这些脂质暴露变构位点的表征将提供进一步的深入了解 AChR 的结构与功能关系。 (2)第二个方法建议引入定期色氨酸替代以覆盖所有 β、γ 和 δ 沿 M4 跨膜结构域的位置亚单位。对一系列色氨酸取代的系统分析将提供螺旋-螺旋或亚基-亚基的物理位置信息对于 AChR 的功能寡聚化至关重要的接触。这可能的约束位点的位置位置可以识别额外的 M4 跨膜结构域的空间组织方面 M1和M3域以及结构-功能关系乙酰胆碱受体。 (3) 第三种方法是利用新型 Torpedo M4 AChR 突变检查脂质-蛋白质界面对各种作用的敏感性全身麻醉药的类型。该项目的目标是定义这些变构位点的生化和生物物理相互作用确定 M4 跨膜空间组织的其他方面 AChR 的结构域。