Studies of P2X ATP Receptors

P2X ATP 受体的研究

• 批准号: 7337313
• 负责人: RICHARD IRWIN HUME
• 金额: $ 31.77万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7337313
• 关键词: ATP Receptors; Agonist; Animals; Architecture; Bacterial Infections; Binding; Binding Sites; Biochemical; Bladder; Bladder Control; Blood; Blood Clot; Blood Platelets; Blood coagulation; Brain; Burn injury; Calcium; Cells; Chromosome Pairing; Class; Coupled; Data; Development; Ejaculation; Endothelial Cells; Family; Family member; Functional disorder; GTP-Binding Proteins; Gastrointestinal tract structure; Gene Family; Genes; Genome; Glutamate Receptor; Glycine Receptors; Goals; Hair Cells; Hepatocyte; Human; Individual; Injury; Invertebrates; Knock-out; Knowledge; Leukocytes; Ligand Binding; Lung; Molecular; Monitor; Movement; Mus; Mutation; Myocardium; Nervous system structure; Neuraxis; Neuroglia; Neuronal Injury; Neurons; Neurotransmitters; Nicotinic Receptors; Numbers; Oxygen; P2X-receptor; Pain; Perception; Peripheral; Peripheral Nervous System; Persistent pain; Phenotype; Phylogenetic Analysis; Physiological Processes; Physiology; Play; Process; Proteins; Purinoceptor; Range; Rattus; Research Personnel; Role; Signal Transduction; Skeletal system; Sorting - Cell Movement; Specificity; Structure; Synapses; Testing; Tissues; Urination; Zinc; cell motility; fighting; gastrointestinal; in vivo; member; receptor; research study; response

The P2X proteins are ATP gated channels that depolarize cells and also allow calcium to enter. P2X receptors are expressed in virtually every tissue, including neurons and glia of the central and peripheral nervous system, smooth, skeletal and cardiac muscle, cochlear hair cells, platelets, most classes of white blood cells, hepatocytes, and endothelial cells in the lung and gastrointestinal tract. The importance of members of this gene family for normal physiology is apparent from the range of phenotypes that are seen in their absence, Mice in which specific P2X receptors are knocked out show dysfunction in pain perception, ability to void the bladder, gut motility, neuronal control of ejaculation, the ability of the nervous system to monitor the oxygen level in the blood, the ability to fight bacterial infection, and blood clotting. A major problem in the purinergic receptor field is the limited specificity of agonists and antagonists that can be used to alter ATP signaling in vivo. The goal of the experiments described here is to better characterize the molecular mechanisms that allow ATP and allosteric modulators to open P2X receptor channels. The results of these studies should facilitate the development of agents tha't act more specifically on particular receptors. We will use electrophysiological, biochemical, and molecular approaches to study receptors bearing complementary mutations in adjacent or non-adjacent subunits. The specific aims are: Goal 1- To test whether the zinc binding sites that modulate channel activity in P2X2, P2X3, and P2X4 receptors are within or between subunits, and to define residues that participate in these binding sites. We will also define our understanding about the mechanisms by which zinc promotes channel opening in P2X2 receptors. Goal 2 - To test whether the ATP binding site of P2X receptors is within or between subunits and to define additional residues that are exposed in the ATP binding pocket. These experiments will also test the number of molecules of ATP that must be bound in order to open a channel. Goal 3 - To define the molecular movements that are a consequence of zinc or ATP binding to P2X2 receptors. These experiments are of particular relevance to making progress in understanding and treating pain associated with tissue injury, as P2X2 and P2X3 receptors have been implicated as playing essential roles as sensing the damage and signaling the central nervous system. Having a better understanding of the structure of these receptors should allow the development of new treatments for this type of pain, and so greatly ease the suffering of individuals with burns and other injuries that produce persistent pain.

P2X 蛋白是 ATP 门控通道，可以使细胞去极化并允许钙进入。 P2X 受体几乎在每个组织中表达，包括中枢和外周的神经元和神经胶质细胞 神经系统、平滑肌、骨骼肌和心肌、耳蜗毛细胞、血小板、大多数类型的白细胞 肺和胃肠道中的血细胞、肝细胞和内皮细胞。的重要性 该基因家族的成员对于正常生理学的影响从以下表型的范围中可以明显看出： 它们的缺失，特定 P2X 受体被敲除的小鼠表现出疼痛感知功能障碍， 排尿膀胱的能力、肠道蠕动、射精的神经元控制、神经系统的能力 监测血液中的氧气水平、抵抗细菌感染的能力和凝血。一个专业 嘌呤能受体领域的问题是可用的激动剂和拮抗剂的特异性有限 改变体内 ATP 信号传导。这里描述的实验的目的是更好地表征 允许 ATP 和变构调节剂打开 P2X 受体通道的分子机制。结果 这些研究应该有助于开发对特定受体没有更特异性作用的药物。 我们将使用电生理学、生物化学和分子方法来研究受体承载 相邻或不相邻亚基的互补突变。具体目标是： 目标 1- 测试锌结合位点是否调节 P2X2、P2X3 和 P2X4 中的通道活性 受体位于亚基内或亚基之间，并定义参与这些结合位点的残基。我们 还将定义我们对锌促进 P2X2 通道开放的机制的理解 受体。 目标 2 - 测试 P2X 受体的 ATP 结合位点是否位于亚基内或亚基之间，并确定 ATP 结合袋中暴露的其他残基。这些实验还将测试数字 必须结合才能打开通道的 ATP 分子。 目标 3 - 定义锌或 ATP 与 P2X2 结合导致的分子运动 受体。 这些实验对于在理解和治疗疼痛方面取得进展特别重要 与组织损伤相关，因为 P2X2 和 P2X3 受体被认为发挥着重要作用 感知损伤并向中枢神经系统发出信号。更好地了解 这些受体的结构应该能够开发出针对此类疼痛的新疗法，等等 大大减轻烧伤和其他造成持续疼痛的伤害的人的痛苦。