Structural biology of the alpha4beta2 nicotinic acetylcholine receptor

α4β2烟碱乙酰胆碱受体的结构生物学

• 批准号: 8681089
• 负责人: Ryan E Hibbs
• 金额: $ 20.14万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8681089
• 关键词: Absence of pain sensation; Agonist; Alcohol consumption; Attenuated; Automobiles; Behavior; Binding; Biochemical; Brain; Cause of Death; Cell Line; Cessation of life; Chewing Gum; Complex; Crystallization; Detergents; Development; Drug usage; Electrophysiology (science); Exhibits; Family; Goals; HIV; Health; Injury; Investigation; Ions; Laboratories; Ligands; Lipid Bilayers; Mediating; Membrane Proteins; Methods; Molecular; Molecular Conformation; Murder; Mus; Neurodegenerative Disorders; Neurotransmitter Receptor; Nicotine; Nicotine Dependence; Nicotinic Receptors; Persons; Phase; Play; Positioning Attribute; Postdoctoral Fellow; Proteins; Research; Resolution; Roentgen Rays; Role; Self Administration; Site-Directed Mutagenesis; Smoker; Source; Structure; Suicide; System; Techniques; Tobacco use; United States; Work; X-Ray Crystallography; base; channel blockers; desensitization; design; new therapeutic target; nicotine replacement; nicotinic receptor alpha4beta2; novel; novel therapeutics; overexpression; receptor; small molecule; smoking cessation; stoichiometry; structural biology; three dimensional structure

DESCRIPTION (provided by applicant): Nicotine addiction is the leading source of preventable death worldwide. The bottleneck in rational design of novel therapeutics for nicotine addiction is high-resolution structural information for nicotinic acetylcholine receptors. Specifically, the alpha4beta2 subtype of the nicotinic receptor plays an essential role in nicotine addiction. Nicotine selectively upregulates this neurotransmitter receptor in systems ranging from clonal cell lines to smokers' brains, and mice lacking the alpha4beta2 receptor exhibit dramatically attenuated nicotine self-administration behavior. The only specific therapy for smoking cessation distinct from nicotine replacement is a partial agonist for the alpha4beta2 nicotinic receptor. Unfortunately, these therapies are only modestly effective in helping people quit smoking. The goal of this proposal is to resolve this pressing biomedical problem by determining the structure of the alpha4beta2 nicotinic receptor by X-ray crystallography. The alpha4beta2 nicotinic receptor is a particularly daunting target for crystallographic studies because it is: (1) a eukaryotic membrane protein; (2) an obligate heteropentameric protein; and (3) its subunit stoichiometry is variable, being formed from either two alpha and three beta subunits, or three alpha and two beta subunits. This proposal is organized into two phases. In the first, exploratory (R21) phase, the goals are to (1) identify alpha4 and beta2 subunit constructs that combine to express at high levels and form stable pentameric receptors, (2) purify a single stoichiometric species of receptor and (3) obtain preliminary crystals. In the second (R33) phase, the goals are to (1) obtain well-diffracting crystals of the alpha4beta2 receptor and (2) determine its structure in complex with different classes of ligands.

描述（由申请人提供）：尼古丁成瘾是全世界可预防死亡的主要原因。合理设计尼古丁成瘾新疗法的瓶颈是烟碱乙酰胆碱受体的高分辨率结构信息。具体来说，烟碱受体的α4β2亚型在尼古丁中起着重要作用 瘾。尼古丁选择性地上调从克隆细胞系到吸烟者大脑等系统中的这种神经递质受体，而缺乏 α4β2 受体的小鼠表现出显着减弱的尼古丁自我给药行为。与尼古丁替代疗法不同的唯一戒烟疗法是α4β2烟碱受体的部分激动剂。不幸的是，这些疗法在帮助人们戒烟方面效果有限。该提案的目标是通过 X 射线晶体学确定 α4β2 烟碱受体的结构来解决这一紧迫的生物医学问题。 α4β2烟碱受体是晶体学研究中特别令人畏惧的目标，因为它是：（1）真核膜蛋白； (2)专性异五聚体蛋白质； (3)其亚基化学计量是可变的，由两个α和三个β亚基、或三个α和两个β亚基形成。该提案分为两个阶段。在第一个探索性 (R21) 阶段，目标是 (1) 鉴定结合高水平表达并形成稳定五聚体受体的 α4 和 β2 亚基构建体，(2) 纯化单一化学计量种类的受体，以及 (3)获得初步晶体。在第二阶段 (R33)，目标是 (1) 获得 α4β2 受体的良好衍射晶体，以及 (2) 确定其与不同类别配体的复合物结构。