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

基本信息

批准号：
7668279
负责人：
SUSAN L HAMILTON
金额：
$ 5.85万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
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/7668279
关键词：
5&apos -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

项目摘要

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（RYR1）调节Ca2+从肌质网中释放（SR）商店，并在人类中心核心疾病（CCD）和药物遗传学综合征中突变，恶性高温（MH）。尽管RYR1中的MH和CCD突变被认为会改变SR Ca2+ 释放通道功能和肌肉激发收缩（EC）耦合，这些机制影响导致这些疾病肌肉特征的表型变化是未知的。这个项目将使用转基因MH和CCD敲入小鼠来提供基本机制的详细分析 RYR1疾病突变会改变体内肌肉功能。该项目的长期目标是定义 MH/CCD突变改变Ca2+稳态，而细胞/分子机制和原理完整肌肉中的激发诱导（EC）耦合。我们的总体假设是：MH和CCD突变 MH/CCD区域1和2通过改变关键内部和 RYR1内的分子间相互作用以及RYR1和电压依赖性Ca2+通道之间的相互作用 T纤维膜，而RyR1区域3孔区域的CCD选择突变破坏Ca2+ 通过通道渗透。为了检验这一假设，我们建议：1。创建三个新的MH/CCD 小鼠线并分析突变对咖啡因响应肌肉收缩特性的影响和温度，2。分析突变对RYR1结构的影响，S.ASSESS RYR1中的MH/CCD突变在CA2+稳态上和MyOutubes中的双向DHPR-RYR1耦合和双向DHPR-RYR1耦合和从MH/CCD敲门小鼠获得的成年肌肉纤维，4评估MH/CCD突变的影响在原位释放频道对RYR1配体激活的敏感性和连接CA2+的局部增加。该应用程序汇集了两个合作者，两者都致力于阐明基本 MH和CCD病理生理学的机制，但他们以截然不同的方式处理问题免费方式。该工会将导致一个独特的跨学科项目，该项目将确定 MH/CCD疾病突变改变RYR1结构和调节的机制，亚细胞CA2+ 运输/处理机制，肌肉EC耦合和SR CA2+存储/隔离。结果将有对Ca2+失调的其他疾病的广泛影响