Structural Studies on Prokaryotic Potassium Channels

原核生物钾通道的结构研究

• 批准号: 8305877
• 负责人: Adrian Gross
• 金额: $ 20.21万
• 依托单位: ROSALIND FRANKLIN UNIV OF MEDICINE & SCI
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-02-01 至 2014-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8305877
• 关键词: Action Potentials; Address; Adverse drug effect; Adverse effects; Affinity; Ammonium; Anti-Arrhythmia Agents; Archaea; Arrhythmia; Binding; Binding Sites; Biochemistry; Biological Models; Calcium Channel; Cell membrane; Cells; Cessation of life; Characteristics; Clinical Medicine; Complex; Cysteine; Data; Dependence; Detergents; Development; Disease; Drug Binding Site; Drug Delivery Systems; Drug usage; Electron Spin Resonance Spectroscopy; Electrophysiology (science); Environment; Epilepsy; Essential Drugs; Functional disorder; Generations; Goals; Heart; Human body; Individual; Intervention; Ion Channel; Ions; Laboratories; Ligands; Lipid Bilayers; Lipids; Membrane; Membrane Potentials; Membrane Proteins; Molecular; Mutagenesis; Neurosciences; Nucleotides; Peripheral; Peripheral Nervous System; Pharmaceutical Preparations; Phylogenetic Analysis; Physiology; Potassium; Potassium Channel; Process; Property; Proteins; Proxy; Resolution; Rest; Seminal; Side; Signal Transduction; Site; Sodium Channel; Spin Labels; Structural Models; Structure; Study models; Testing; Tissues; Water; Work; X-Ray Crystallography; base; drug development; novel; prokaryotic potassium channel; public health relevance; quaternary ammonium compound; receptor; sensor; voltage

DESCRIPTION (provided by applicant): Ion channels are instrumental in the generation of membrane potential, receptor potential, and action potential. They are the molecular building blocks for what is an essential characteristic of many cells in neuroscience: excitability. These proteins are implicated in the physiology and pathophysiology of all excitable tissues, underlie many disease processes including epilepsies and arrhythmias, and are major targets of essential drugs used in clinical medicine. Potassium channels are the phylogenetic founders of a large superfamily of structurally related ion channels that includes nucleotide gated channels, sodium channels, and calcium channels. Potassium channels are typically assembled from four identical subunits in a four-fold symmetrical fashion. This rather simple structural blueprint and the substantial practical advantage of only one subunit type have made potassium channels a much studied model system. This proposal explores two aspects of potassium channels: drug binding and voltage- dependence. In aim 1 we will determine the structural basis of the drug-channel interaction. In aim 2 we will attempt to describe the voltage-sensing domain of the channel in its native form. We will use a combination of cysteine mutagenesis, biochemistry, electrophysiology, site-directed spin labeling, and X-ray crystallography to study two prokaryotic potassium channels: KcsA and KvAP. The long-term goal of this proposal is to understand functional properties of ion channels at a structural level. PUBLIC HEALTH RELEVANCE: Ion channels are membrane proteins that allow ions to pass from one side of the cell membrane to the other. They are the molecular hardware that generates all electrical signals in the human body. These signals are used to coordinate the beating of the heart and underlie the complex function of the central and peripheral nervous system. When ion channels malfunction, serious maladies ensue, such as heart arrhythmias, epilepsy, and even death. Ion channels are also important drug targets. Drugs effecting ion channels are used every day in clinical medicine and are often implicated in serious drug side effects. Determining the precise structure and mechanism of action of these channels will allow for the development of safer and more effective drugs.

描述（由申请人提供）：离子通道有助于膜电位、受体电位和动作电位的产生。它们是神经科学中许多细胞的基本特征：兴奋性的分子构建块。这些蛋白质与所有兴奋组织的生理学和病理生理学有关，是包括癫痫和心律失常在内的许多疾病过程的基础，并且是临床医学中使用的基本药物的主要靶标。钾通道是结构相关离子通道大家族的系统发育奠基者，其中包括核苷酸门控通道、钠通道和钙通道。钾通道通常由四个相同的亚基以四重对称的方式组装而成。这种相当简单的结构蓝图和仅一种亚基类型的巨大实际优势使钾通道成为备受研究的模型系统。该提案探讨了钾通道的两个方面：药物结合和电压依赖性。在目标 1 中，我们将确定药物通道相互作用的结构基础。在目标 2 中，我们将尝试以原始形式描述通道的电压感应域。我们将结合使用半胱氨酸诱变、生物化学、电生理学、定点自旋标记和 X 射线晶体学来研究两种原核钾通道：KcsA 和 KvAP。该提案的长期目标是在结构水平上了解离子通道的功能特性。 公共健康相关性：离子通道是膜蛋白，允许离子从细胞膜的一侧传递到另一侧。它们是产生人体内所有电信号的分子硬件。这些信号用于协调心脏的跳动，是中枢和周围神经系统复杂功能的基础。当离子通道出现故障时，就会出现严重的疾病，例如心律失常、癫痫，甚至死亡。离子通道也是重要的药物靶点。影响离子通道的药物每天都在临床医学中使用，并且常常涉及严重的药物副作用。确定这些通道的精确结构和作用机制将有助于开发更安全、更有效的药物。