Sodium and Calcium Channels: Structure, Function, Neuroplasticity, and Disease

钠和钙通道：结构、功能、神经可塑性和疾病

• 批准号: 9923774
• 负责人: WILLIAM A CATTERALL
• 金额: $ 111.16万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-05-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/9923774
• 关键词: Action Potentials; Aging; Ataxia; Brain; Calcium; Calcium Channel; Calmodulin; Cessation of life; Characteristics; Childhood; Circadian Rhythm Sleep Disorders; Cognitive deficits; Combined Modality Therapy; Communication; Complex; Cre-LoxP; Disease; Elements; Epilepsy; Erythromelalgia; Failure; Functional disorder; Genetic Models; Genetic study; Hippocampus (Brain); Impairment; Inherited; Interneurons; Ion Channel; Ions; Learning; Memory; Methods; Migraine; Modification; Molecular; Molecular Structure; Mus; Mutation; Neurodegenerative Disorders; Neuronal Plasticity; Neurons; Paroxysmal extreme pain disorder; Physiological; Process; Property; Proteins; Regulation; Resolution; Role; Seizures; Signal Transduction; Signaling Protein; Site; Sodium; Sodium Channel; Status Epilepticus; Structure; Synapses; Synaptic Transmission; Synaptic plasticity; Syndrome; Work; X-Ray Crystallography; autistic; base; chronic pain; dravet syndrome; excitatory neuron; experimental study; in vivo; insight; loss of function mutation; molecular drug target; mouse genetics; mouse model; neural circuit; neuropsychiatric disorder; neurotransmitter release; next generation; novel; novel strategies; periodic paralysis; premature; presynaptic; sensor; sudden unexpected death in epilepsy; three dimensional structure; voltage

Voltage-gated sodium (Nav) and calcium (Cav) channels generate action potentials and initiate synaptic transmission in neurons. Mutations in them cause inherited epilepsy, migraine, chronic pain, and periodic paralysis, and they are important molecular targets for drugs. A. New insights into structure and function of Nav channels have come from our high-resolution x-ray crystallography of their bacterial ancestor NavAb. We will further define the structural basis for key functional properties of mammalian Nav channels by building their characteristic structural features into NavAb, including the structural basis for voltage-dependent activation, ion selectivity, and fast inactivation. Based on these results, we will determine the structural basis for impaired Nav channel function by mutations that cause periodic paralysis and the chronic pain syndromes erythromelalgia and paroxysmal extreme pain disorder. B. Failure of learning and memory is a debilitating aspect of aging and neurodegenerative disease, yet we do not understand the basic mechanisms of these crucial brain processes and we cannot intervene effectively in these deficits. Learning and memory takes place primarily at synapses. Presynaptic calcium (Cav2.1) channels initiate neurotransmitter release at most synapses in the brain. The activity of these channels is tightly regulated by a large complex of signaling proteins, including calmodulin and related calcium-sensor proteins. Our work implicates Cav2.1 channel regulation in short-term synaptic plasticity in transfected synapses in cultured neurons and in a novel mouse model in which the IM-AA mutation is inserted into Cav2.1. We will further define the molecular and structural mechanism for Cav2.1 channel regulation, determine the role of regulation of Cav2.1 channels in short-term synaptic plasticity of neural circuits, and explore the role of regulation of Cav2.1 channels and short-term synaptic plasticity in spatial learning and memory. Our experiments with this unique mouse model will give unique insights into the mechanism of short-term presynaptic plasticity in hippocampal neurons and its role in integrative bbrain function. C. Dravet Syndrome (DS) is a devastating childhood neuropsychiatric disorder caused by de novo, heterozygous loss-of-function mutations in Nav1.1. We developed a mouse genetic model with all the features of DS, including thermally induced and spontaneous seizures, ataxia, circadian rhythm and sleep disorders, cognitive deficit, autistic-like features, and premature death via SUDEP. Physiological and genetic studies show that all these effects are correlated with loss of Na currents and excitability of GABAergic interneurons, without consistent effects on excitatory neurons, which causes imbalance of excitation vs. inhibition in neural circuits. To further advance understanding of pathophysiology and treatment of DS, we will determine the neural cells and circuits responsible for DS using specific deletion by the Cre-Lox method, identify the sites of hyperexcitability in neural cells and circuits that appear first in DS mice in vivo, and optimize next-generation combination therapy for seizures, status epilepticus, cognitive deficit, and premature death in DS.

电压门控钠（Nav）和钙（Cav）通道产生动作电位并启动突触传递。 神经元中的传递。它们的突变会导致遗传性癫痫、偏头痛、慢性疼痛和周期性疼痛。 瘫痪，它们是药物的重要分子靶点。A.对Nav结构和功能的新认识 这些通道来自于我们对其细菌祖先NavAb的高分辨率X射线晶体学。我们将 进一步定义哺乳动物Nav通道关键功能特性的结构基础， 特征性结构特征，包括电压依赖性激活的结构基础，离子 选择性和快速失活。基于这些结果，我们将确定受损的NAV的结构基础 通道功能的突变，导致周期性麻痹和慢性疼痛综合征红斑性肢痛症 和阵发性极度疼痛障碍B。学习和记忆的失败是衰老的一个衰弱方面， 神经退行性疾病，但我们不了解这些关键的大脑过程的基本机制 我们无法有效地干预这些赤字。学习和记忆主要发生在突触上。 突触前钙（Cav2.1）通道在大脑中的大多数突触处启动神经递质释放。的 这些通道的活性受到大量信号蛋白复合物的严格调节，包括钙调蛋白和 相关的钙敏感蛋白。我们的工作暗示Cav2.1通道调节短期突触可塑性 在培养的神经元中的转染突触中，以及在一种新的小鼠模型中， 插入Cav2.1。我们将进一步阐明Cav2.1通道的分子和结构机制 调节，确定Cav2.1通道在神经元短时程突触可塑性中的调节作用。 电路，并探讨Cav2.1通道的调节和空间的短时突触可塑性的作用 学习和记忆。我们用这种独特的小鼠模型进行的实验将为我们提供独特的见解， 海马神经元突触前短时程可塑性机制及其在脑整合中的作用 功能C. Dravet综合征（DS）是一种毁灭性的儿童神经精神障碍， Nav1.1中的杂合功能丧失突变。我们开发了一个小鼠遗传模型， 包括热诱导和自发性癫痫发作、共济失调、昼夜节律和睡眠障碍， 认知缺陷、自闭症样特征和通过SUDEP导致的过早死亡。生理和遗传研究 结果表明，所有这些效应都与Na电流的丧失和GABA能中间神经元的兴奋性有关， 对兴奋性神经元没有一致的影响，这导致神经元中兴奋与抑制的不平衡。 电路.为了进一步了解DS的病理生理学和治疗，我们将确定 通过Cre-Lox方法使用特异性缺失，识别负责DS的神经细胞和回路， 神经细胞和回路中的过度兴奋首先出现在DS小鼠体内，并优化下一代 联合治疗DS患者的癫痫发作、癫痫持续状态、认知缺陷和过早死亡。