Defining Alcohol Binding Sites in Ligand-Gated Ion Channels

定义配体门控离子通道中的醇结合位点

• 批准号: 8877373
• 负责人: JAMES Robert TRUDELL
• 金额: $ 30.34万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8877373
• 关键词: 3-Dimensional; Acetylcholine; Address; Affect; Alcohol abuse; Alcohol dependence; Alcoholism; Alcohols; Algorithms; Amino Acids; Binding; Binding Sites; Bioinformatics; Chloride Channels; Computational Biology; Computer Simulation; Conflict (Psychology); Cysteine; Data; Disulfides; Docking; Ethanol; Future; GABA Receptor; Gated Ion Channel; Glutamates; Glycine; Goals; Health; Homologous Gene; Homology Modeling; Imagery; Ion Channel; Ion Channel Protein; Ions; Knowledge; Laboratories; Ligand Binding; Ligands; Location; Maps; Measures; Mediating; Methods; Modeling; Molecular Biology; Molecular Models; Mutate; Mutation; National Institute on Alcohol Abuse and Alcoholism; Nervous system structure; Neurons; Oocytes; Pathway interactions; Pharmaceutical Preparations; Positioning Attribute; Property; Protons; Publications; Reagent; Research; Research Personnel; Resources; Roentgen Rays; Series; Serotonin Receptors 5-HT-3; Site; Solutions; Structure; Sulfhydryl Compounds; Synapses; Synaptic Receptors; System; Techniques; Testing; Texas; United States National Institutes of Health; Universities; addiction; alcohol abuse therapy; alcohol effect; alcohol research; alcohol sensitivity; alpha helix; analog; austin; base; computational neuroscience; cost; craving; design; improved; innovation; methanethiosulfonate; model building; molecular modeling; novel; pharmacophore; programs; receptor; relating to nervous system; screening; success; three-dimensional modeling

DESCRIPTION (provided by applicant): Alcohol abuse and alcoholism are significant health problems that affect over 17 million people and cost nearly $200 billion annually. It is likely tha a solution to these problems will result from a better understanding of alcohol effects on neuronal ion channels and the proteins that modulate them. The goal of the proposed research will be a significant step towards understanding the properties of alcohol-binding sites at an atomic level. We believe this knowledge will be essential for future design and selection of drugs that could reduce craving or addiction induced by alcohol. Specifically, we will study the sites fo alcohol binding in ligand- gated ion channels (LGICs), which include GABAaRs and GlyRs. Our homology modeling and experimental methods will provide 3-dimensional visualization of GABAaRs to increase our understanding of alcohol's action. This innovative approach combines cutting-edge computational and neuroscience techniques with molecular biology. We expect our results will have a significant impact on the broader class of alcohol- binding sites in other important receptors of the nervous system. Our Approach focuses on three aspects of alcohol-binding sites via three Specific Aims: Where are alcohol-binding sites; intra-subunit versus inter- subunit in LGICs (Aim 1), which specific residues or segments in LGICs mediate the effect of alcohol binding at these sites (Aims 1 and 2), and how do these sites modulate ligand binding (Aims 2 and 3). In Aim 1, Trudell and Bertaccini will build computational models of alcohol-binding sites in GABA receptors and design site-directed mutations to test the models. Harris and Howard, under a subcontract to the University of Texas, Austin, will test the function of these mutated receptors. We will iteratively refine the models the Trudell group will use the models to predict the effects of mutations; the Harris group will test if the models are consistent with experimental data; and the Trudell group will then modify the models to fit the new data. They will address this controversial question: What is the most important alcohol effect site in GABAaR? Is it Intra-subunit or Inter-subunit? They will also test the hypothesis that the GABAaR TM3 helix must rotate during activation in order to incorporate all recent experimental data. In Aim 2, the Trudell and Harris laboratories will recreate the alcohol-binding site from GABAaRs in the homologous but natively EtOH insensitive ion channel, GLIC, by determining which residues are specific to EtOH binding in GABAR and mutating these into their corresponding homologous positions within GLIC. In Aim 3, Trudell and Bertaccini will use three docking programs to investigate binding of alcohol analogs. Our investigators have proven accomplishment in alcohol research and possess the resources necessary to accomplish our Aims. Our proposal is responsive to both the NIAAA initiative in computational neuroscience and the NIH Roadmap: Bioinformatics and Computational Biology. These significant studies will provide essential knowledge needed to design alcohol-binding antagonists which could revolutionize treatment for alcohol abuse and dependence.

描述（由申请人提供）：酗酒和酒精中毒是影响超过1700万人的重大健康问题，每年耗资近2000亿美元。解决这些问题的解决方案可能是由于对酒精对神经元离子通道的影响和调节它们的蛋白质的影响而产生的。拟议的研究的目标将是了解原子水平上酒精结合位点的特性的重要一步。我们认为，这些知识对于将来的设计和选择可以减少酒精引起的渴望或成瘾的药物至关重要。具体而言，我们将研究包括Gabaars和Glyrs在内的配体离子通道（LGIC）中酒精结合的位置。我们的同源性建模和实验方法将提供3维的Gabaars可视化，以增加我们对酒精作用的理解。这种创新的方法将尖端计算和神经科学技术与分子生物学结合在一起。我们预计我们的结果将对神经系统其他重要受体中更广泛的酒精结合位点产生重大影响。我们的方法通过三个特定目的着重于酒精结合部位的三个方面：酒精结合部位在哪里；基因内与间的 LGICS中的亚基（AIM 1），LGIC中的特定残基或片段介导了这些位点的酒精结合的作用（AIMS 1和2），以及这些位点如何调节配体结合（目标2和3）。 在AIM 1中，Trudell和Bertaccini将在GABA受体中建立酒精结合位点的计算模型，并在设计位置定向的突变中以测试模型。哈里斯（Harris）和霍华德（Howard），根据德克萨斯大学奥斯汀分包合同，将测试这些突变受体的功能。我们将迭代地完善特鲁德尔组将使用模型预测突变影响的模型；哈里斯组将测试模型是否一致 使用实验数据；然后Trudell组将修改模型以适合新数据。他们将解决这个有争议的问题：加巴尔最重要的酒精效应网站是什么？是亚基内或亚基间的吗？他们还将检验以下假设：GABAAR TM3螺旋在激活过程中必须旋转以结合所有最新的实验数据。在AIM 2中，Trudell和Harris实验室将通过确定哪些残基特异性与Gabar中的EtOH结合并将其突变为其在Glic中的相应同源位置，从而在同源但本质上不敏感的离子通道中重新创建酒精结合位点。在AIM 3中，Trudell和Bertaccini将使用三个停靠计划来研究酒精类似物的结合。我们的调查人员在酒精研究中已证明了成就，并拥有实现我们目标所需的资源。我们的建议对计算神经科学和NIH路线图的NIAAA倡议均反应：生物信息学和计算生物学。这些重要的研究将提供设计酒精结合拮抗剂所需的基本知识，这些拮抗剂可能会彻底改变酒精滥用和依赖性的治疗。