LIGAND BINDING SITES OF THE ACETYLCHOLINE RECEPTOR

乙酰胆碱受体的配体结合位点

• 批准号: 6393797
• 负责人: STEEN E PEDERSEN
• 金额: $ 31.59万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-06-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6393797
• 关键词: Torpedo; acetylcholine; aminoacid; binding sites; cell line; chemical kinetics; chimeric proteins; combinatorial chemistry; conformation; diffusion; electric field; electrochemistry; fluorescence resonance energy transfer; high performance liquid chromatography; ionic bond; membrane channels; molecular energy level; nicotinic receptors; protein structure function; receptor binding; receptor sensitivity; site directed mutagenesis; stereochemistry; tubocurarine

The long-term aim of this research is to understand the regulation of ligand-gated ion channels by the binding of neurotransmitters. The particular goal of this application is to understand the importance of charge-charge interactions in the regulation of the nicotinic acetylcholine receptor by the binding of acetylcholine. Specifically, the structure activity relationship of d-tubocurarine to the nicotinic acetylcholine receptor will be examined by analyzing the binding of d-tubocurarine analogs to native and mutated acetylcholine receptors. The role of electrostatic attraction in binding will be examined to determine whether charge- charge attraction governs the rapid rate of acetylcholine binding and contributes to the stabilization of the agonist cation. The channel movements associated with the conformational transition of the acetylcholine receptor will be measured by mutagenesis of residues near the narrow pore of the channel, and by direct measurements of electrostatic potential using fluorescence lifetime spectroscopic methods. The experiments will define functionally relevant components of the receptor structure that contribute to ligand binding, to ion channel structure, and to function. This will improve our understanding of synaptic transmission, a process that underlies the complex phenomena of learning, memory and thought. The skeletal muscle nicotinic acetylcholine receptor (and particularly the extracellular domain) is the target of autoimmune antibodies in the disease Myasthenia Gravis. The neuronal homologues of this protein are involved in nicotine addiction and possibly in Alzheimer's disease. A better understanding of the structure of this protein and especially the acetylcholine binding sites will be important for a full understanding of these ailments and for developing treatments. A fundamental understanding of the binding site stricture will improve rational drug design for this protein while the methodology proposed here may constitute a new paradigm for rational drug design for receptor targets in general.

这项研究的长期目标是了解神经递质结合对配体门控离子通道的调节。本申请的具体目标是了解电荷-电荷相互作用在通过乙酰胆碱结合调节烟碱乙酰胆碱受体中的重要性。具体而言，将通过分析d-筒箭毒碱类似物与天然和突变的乙酰胆碱受体的结合来检查d-筒箭毒碱与烟碱乙酰胆碱受体的结构活性关系。将检查静电吸引力在结合中的作用，以确定电荷-电荷吸引力是否控制乙酰胆碱结合的快速速率并有助于激动剂阳离子的稳定。与乙酰胆碱受体构象转变相关的通道运动将通过通道窄孔附近的残基诱变来测量，并通过使用荧光寿命光谱方法直接测量静电势来测量。这些实验将定义受体结构的功能相关成分，这些成分有助于配体结合、离子通道结构和功能。这将提高我们对突触传递的理解，突触传递是学习、记忆和思维复杂现象的基础。骨骼肌烟碱乙酰胆碱受体（特别是细胞外结构域）是重症肌无力疾病中自身免疫抗体的靶标。该蛋白的神经元同源物与尼古丁成瘾有关，并可能与阿尔茨海默病有关。更好地了解这种蛋白质的结构，尤其是乙酰胆碱结合位点，对于充分了解这些疾病和开发治疗方法非常重要。对结合位点狭窄的基本了解将改善该蛋白质的合理药物设计，而本文提出的方法可能构成一般受体靶标合理药物设计的新范例。