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。 神经型烟碱型乙酰胆碱受体(NAChRs)的结合部位。 神经元nAChRs之所以令人感兴趣，有几个原因。神经元nAChRs是 尼古丁发挥其精神活性和成瘾作用的部位 尼古丁配体还可能用作抗焦虑和止痛剂， 在治疗精神分裂症等神经疾病时， 帕金森氏症和阿尔茨海默氏症。因此在药理上 对神经元nAChRs的干预有望治疗 中枢神经系统疾病，以及对疾病的了解和治疗 令人上瘾的过程。实现这一潜力的关键是 亚型选择性nAChR配体的研究进展追求这一目标 需要了解配体结合的分子结构 神经元nAChRs的位置。具体地说，尼古丁的特征 负责nAChR亚型选择性的结合位点必须是 已确认身份。 神经元nAChR家族由大量相关亚基组成， 它们可以以各种组合的形式结合在一起，形成药理上的 截然不同的受体。这些受体上的配基结合部位是 复合体，每个由来自于 两个不同的亚基。我们将鉴定其上的氨基酸残基 神经元nAChR亚单位对激动剂和竞争性受体具有特异性 拮抗剂使用分子生物学、 电生理学和药理学技术。我们将确定 神经元nAChRs等多肽拮抗剂上的关键氨基酸残基 作为神经性银环蛇毒素，通过研究一系列重组突变型毒素 准备工作。有了这些信息，我们将使用突变循环分析 为了鉴定毒素和受体上相互作用的残基对，最终 导致了一种基于实验的氨基酸的三维模型 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.