BINDING SITE STRUCTURE OF NEURONAL NICOTINIC RECEPTORS

描述：（申请人摘要） 这个项目旨在了解神经递质的结构 神经元烟碱乙酰胆碱受体（nAChR）的结合位点。 神经元nAChR由于几个原因而受到关注。 神经元nAChR是 尼古丁发挥其精神活性和成瘾作用的部位 烟碱配体也可能用作抗焦虑药和镇痛药， 以及在治疗神经疾病如精神分裂症中， 帕金森氏症和阿尔茨海默氏症。 因此，药理学 对神经元nAChRs的干预有望治疗 中枢神经系统疾病，以及了解和治疗 上瘾的过程 实现这一潜力的关键是 亚型选择性nAChR配体的开发。 实现这一目标 需要了解配体结合的分子结构 神经元nAChRs的位点。 具体来说，尼古丁的特征 负责nAChR亚型选择性的结合位点必须是 鉴定 神经元nAChR家族由大量相关亚基组成， 其可以以各种组合形式缔合以形成聚合物 不同的受体 这些受体上的配体结合位点是 复合物，每个复合物由来自以下的几个氨基酸序列片段形成： 两个不同的亚单位 我们将确定氨基酸残基上 神经元nAChR亚单位赋予激动剂和竞争性 使用分子生物学， 电生理学和药理学技术。 我们将确定 神经元nAChR的肽拮抗剂上的关键氨基酸残基，如 神经元银环蛇毒素，通过研究一系列重组突变毒素， 准备工作 有了这些信息，我们将使用突变周期分析 来鉴定毒素和受体上相互作用的残基对， 从而形成了一个基于实验的氨基酸三维模型 决定亚型特异性的神经元nAChR残基。

DESCRIPTION: (Applicant's Abstract) This project is aimed at understanding the structure of the neurotransmitter binding sites of neuronal nicotinic acetylcholine receptors (nAChRs). Neuronal nAChRs are of interest for several reasons. Neuronal nAChRs are the sites at which nicotine exerts its psychoactive and addictive effects Nicotinic ligands are also potentially useful as anxiolytics and analgesics, and in the treatment of neurological disorders such as schizophrenia, Parkinson's disease, and Alzheimer's disease. Thus pharmacological intervention at neuronal nAChRs holds promise for treating the effects of diseases of the central nervous system, and for understanding and treating addictive processes. Critical to the realization of this potential is the development of subtype selective nAChR ligands. Pursuit of this goal requires an understanding of the molecular structure of the ligand binding sites of neuronal nAChRs. Specifically, the features of the nicotinic binding sites that are responsible for nAChR subtype selectivity must be identified. The neuronal nAChR family consists of a large number of related subunits, which can associate in a variety of combinations to form pharmacologically distinct receptors. The ligand binding sites on these receptors are complex, each being formed by several segments of amino acid sequence from two different subunits. We will identify the amino acid residues on neuronal nAChR subunits that confer specificity for agonists and competitive antagonists using a combination of molecular biological, electrophysiological and pharmacological techniques. We will identify critical amino acid residues on peptide antagonists of neuronal nAChRs, such as Neuronal Bungarotoxin, by studying a series of recombinant mutant toxin preparations. With this information, we will then use mutant cycle analysis to identify interacting pairs of residues on toxin and receptor, ultimately leading to an experimentally-based, three-dimensional model of amino acid residues of neuronal nAChR that determine subtype specificity.