Basis of Muscle Dysfunction in Malignant Hyperthermia and Central Core Disease

恶性高热和中央核心疾病中肌肉功能障碍的基础

• 批准号: 7380011
• 负责人: SUSAN L HAMILTON
• 金额: $ 22.42万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7380011
• 关键词: 5' -adenylyl (beta,gamma-methylene)diphosphonate; Adult; Affinity; Aging; Amino Acids; Anesthetics; Binding; Birth; Caffeine; Central Core Myopathy; Characteristics; Commit; Coupling; Cresol; Cresols; Cryoelectron Microscopy; Cytoplasm; Dependence; Dihydropyridine Receptors; Disease; Elevation; Embryo; Exercise; Fiber; Figs - dietary; Flexor; Functional disorder; Gifts; Goals; Heating; Homeostasis; Human; In Situ; Isoflurane; Knock-in Mouse; Knock-out; Label; Laboratories; Lead; Left; Ligands; Lipid Bilayers; Malignant hyperpyrexia due to anesthesia; Maps; Membrane; Molecular; Mus; Muscle; Muscle Fibers; Muscle function; Mutant Strains Mice; Mutate; Mutation; Numbers; Partner in relationship; Permeability; Pharmacogenetics; Property; Proteins; Rate; Regulation; Research Personnel; Resolution; Respiratory Diaphragm; Respiratory Failure; Rest; RyR1; RyR3; Ryanodine; Ryanodine Receptor Calcium Release Channel; Sarcoplasmic Reticulum; Skeletal Muscle; Skeletal system; Structure; Surface; Syndrome; Temperature; Testing; Thinking; Transgenic Organisms; Variant; Wild Type Mouse; base; day; disease-causing mutation; embryonic stem cell; image reconstruction; improved; in vivo; intermolecular interaction; knockout animal; mutant; novel; programs; reconstitution; reconstruction; response; three dimensional structure; voltage

The skeletal muscle ryanodine receptor (RYR1) regulates Ca2+ release from the sarcoplasmic reticulum (SR) stores and is mutated in human central core disease (CCD) and in the pharmacogenetic syndrome, malignant hyperthermia (MH). Although MH and CCD mutations in RyR1 are thought to alter SR Ca2+ release channel function and muscle excitation-contraction (EC) coupling, the mechanisms by which these effects result in phenotypic changes in muscle characteristic of these disorders are unknown. This project will use transgenic MH and CCD knock-in mice to provide detailed analyses of the fundamental mechanisms by which RYR1 disease mutations alter in vivo muscle function. The long-term goal of this project is to define the cellular/molecular mechanisms and principles by which MH/CCD mutations alter Ca2+ homeostasis and excitation-contraction (EC) coupling in intact muscle. Our overall hypothesis is: MH and CCD mutations in MH/CCD regions 1 and 2 enhance voltage- and Ca2+-gated SR release by altering crucial intra and intermolecular interactions within RYR1 and between RYR1 and the voltage dependent Ca2+ channel in the t-tubule membrane, while CCD-selective mutations in the region 3 pore region of RyR1 disrupt Ca2+ permeation through the channel. To test this hypothesis, we propose to: 1. Create three new MH/CCD mouse lines and analyze the effects of the mutations on muscle contractile properties in response to caffeine and temperature, 2. Analyze the effects of the mutations on RYR1 structure, S.Assess the effects of MH/CCD mutations in RyR1 on Ca2+ homeostasis and bi-directional DHPR-RyR1 coupling in myotubes and adult muscle fibers obtained from MH/CCD knock-in mice, and 4 Evaluate the effects of MH/CCD mutations on in situ release channel sensitivity to activation by RyR1 ligands and local increases in junctional Ca2+. This application brings together two collaborators, both highly committed to elucidating fundamental mechanisms of MH and CCD pathophysiology, but who approach the problems in very different, but complimentary ways. This union will result in a uniquely interdisciplinary project that will determine the mechanisms by which MH/CCD disease mutations alter RyR1 structure and regulation, subcellular Ca2+ transport/handling mechanisms, muscle EC coupling, and SR Ca2+ storage/sequestration. Results will have broad implications for other disorders of Ca2+ dysregulation in

骨骼肌Ryanodine受体（RYR 1）调节肌浆网的Ca 2+释放 (SR)在人类中央核心疾病（CCD）和药物遗传学综合征中储存并突变， 恶性高热（MH）。虽然RyR 1中的MH和CCD突变被认为改变了SR Ca 2 + 释放通道功能和肌肉兴奋-收缩（EC）耦合，这些机制 导致这些疾病的肌肉特征的表型变化的作用是未知的。这个项目 将使用转基因MH和CCD基因敲入小鼠来提供基本机制的详细分析 RYR 1疾病突变通过其改变体内肌肉功能。该项目的长期目标是确定 MH/CCD突变改变Ca 2+稳态的细胞/分子机制和原理， 兴奋-收缩（EC）偶联。我们的总体假设是： MH/CCD区域1和2通过改变关键的内部和外部环境来增强电压门控和Ca 2+门控SR释放。 RYR 1内的分子间相互作用以及RYR 1与电压依赖性Ca 2+通道之间的相互作用 t-小管膜，而RyR 1的区域3孔区域中的CCD选择性突变破坏Ca 2 + 通过通道渗透。为了验证这一假设，我们建议：1。创建三个新的MH/CCD 小鼠品系，并分析突变对响应咖啡因的肌肉收缩特性的影响 温度，2。分析突变对RYR 1结构的影响，S。 RyR 1中的MH/CCD突变对肌管中Ca 2+稳态和双向DHPR-RyR 1偶联的影响， 从MH/CCD基因敲入小鼠获得的成年肌纤维，和4评估MH/CCD突变的影响 对RyR 1配体激活的原位释放通道敏感性和连接Ca 2+的局部增加。 这个应用程序汇集了两个合作者，都高度致力于阐明基本的 MH和CCD的病理生理学机制，但谁的方法在非常不同的问题，但 恭维的方式。这个联盟将产生一个独特的跨学科项目，该项目将决定 MH/CCD疾病突变改变RyR 1结构和调节的机制，亚细胞Ca 2 + 运输/处理机制，肌肉EC偶联和SR Ca 2+储存/螯合。结果将有 对其他钙离子失调疾病的广泛影响，