Mechanisms of resealing and rebuilding in muscle repair

肌肉修复中的重新封闭和重建机制

• 批准号: 10734597
• 负责人: ALEXIS R. DEMONBREUN
• 金额: $ 40万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10734597
• 关键词: Actins; Acute; Annexin A6; Annexins; Area; Cells; Chronic Disease; Cytoplasm; DNA Sequence Alteration; DYSF gene; Defect; Dependence; Disease; Dominant-Negative Mutation; Event; Extracellular Matrix; F-Actin; Family member; Genetic; Genetic Diseases; Health; Homologous Gene; Hour; Injury; Membrane; Molecular; Muscle; Muscle Contraction; Muscle function; Muscular Atrophy; Muscular Dystrophies; Myoblasts; Outcome; Pharmacology; Phase; Polymers; Process; Proliferating; Proteins; Research; Resolution; Role; Sarcolemma; Sarcomeres; Shoulder; Site; Therapeutic; Time; Trauma; Visualization; Work; cell motility; cell type; extracellular; improved; injured; injury and repair; migration; novel; polymerization; progenitor; programs; recruit; repaired; seal; tool; Actins; Acute; Annexin A6; Annexins; Area; Cells; Chronic Disease; Cytoplasm; DNA Sequence Alteration; DYSF gene; Defect; Dependence; Disease; Dominant-Negative Mutation; Event; Extracellular Matrix; F-Actin; Family member; Genetic; Genetic Diseases; Health; Homologous Gene; Hour; Injury; Membrane; Molecular; Muscle; Muscle Contraction; Muscle function; Muscular Atrophy; Muscular Dystrophies; Myoblasts; Outcome; Pharmacology; Phase; Polymers; Process; Proliferating; Proteins; Research; Resolution; Role; Sarcolemma; Sarcomeres; Shoulder; Site; Therapeutic; Time; Trauma; Visualization; Work; cell motility; cell type; extracellular; improved; injured; injury and repair; migration; novel; polymerization; progenitor; programs; recruit; repaired; seal; tool

Muscle repair is essential to maintain normal muscle function. Muscle injury, whether due to trauma or overuse, is associated with a loss of muscle membrane integrity. Resealing the disrupted sarcolemma is a critical step needed for muscle repair. Subtypes of muscular dystrophy arise from genetic mutations that weaken the sarcolemma, rendering it prone to disruption and requiring robust repair mechanisms. Other subtypes of muscular dystrophy arise from genetically-driven deficits in repair proteins, and these genetic disorders have illustrated proteins and mechanisms that contribute to membrane stability and membrane repair. Studies of injured muscle and dystrophic muscle have uncovered phases of muscle repair, an immediate resealing phase followed by a rebuilding phase. Sarcolemmal resealing occurs through the formation of a cap at the site of muscle membrane disruption. We and others have shown that this cap is enriched for annexin proteins, especially annexin A6, a modifier of muscular dystrophy. Dominant negative annexin A6 disrupts the formation of the repair cap, through its effects on annexin assembly, leading to excessive membrane leak and ineffective repair. The repair cap is supported by a ring of “shoulder” proteins that serve to reinforce the resealing process, and these proteins include dysferlin, MG53, and EHD proteins. Within the muscle cytoplasm immediately abutting sarcolemmal disruption is an active area that is enriched for actin and the dysferlin related protein, Fer1L5. Moreover, actin polymerization is required for normal resealing. Recent work highlighted the role of muscle rebuilding, which follows sarcolemma resealing and includes sarcomere assembly. Through this research program, we previously demonstrated the role of ferlin proteins and annexins in sarcolemmal resealing by optimizing high-resolution real-time visualization. We also developed novel genetic tools to elucidate the interaction of these proteins in membrane events. We now propose to investigate the role of resealing proteins in their interaction with the actin-rich region in Aim 1. In Aim 2, we will examine the molecular and temporal overlap of resealing and rebuilding during muscle repair. In Aim 3, we will use biologically active decellularized matrices to define and probe the role of extracellular annexins in regulating cellular contributions to muscle repair in health and disease. The outcomes of this work will discover new protein-cellular interactions to guide the pharmacology of promoting muscle repair.

肌肉修复对于维持正常的肌肉功能至关重要。肌肉损伤，无论是由于创伤还是 过度使用，与肌肉膜完整性的丧失有关。重新密封被破坏的肌体是一个 肌肉修复所需的关键步骤。肌肉营养不良的亚型是由基因突变引起的 削弱肌肉症，使其容易破坏并需要强大的修复机制。其他 肌肉营养不良的亚型是由遗传驱动的修复蛋白缺陷以及这些遗传 疾病说明了有助于膜稳定性和膜的蛋白质和机制 维修。肌肉和营养不良的肌肉的研究具有发现肌肉修复的阶段，这是 立即重新密封阶段，然后进行重建阶段。肌膜重新密封通过 在肌肉膜破坏部位形成帽子。我们和其他人表明这个帽子是 富含肌肉营养不良症改良剂的膜联蛋白，尤其是膜联蛋白A6。占主导地位 膜联蛋白A6通过对膜联蛋白组装的影响破坏了维修帽的形成，导致 膜泄漏过多和无效修复。维修帽由“肩膀”蛋白的环支撑 这有助于加强重新密封过程，这些蛋白质包括Dysferlin，MG53和EHD蛋白。 在肌肉细胞质内立即毗邻肌毛膜破坏，是一个充满活性的区域 肌动蛋白和dysferlin相关蛋白，FER1L5。此外，正常重新密封需要肌动蛋白聚合。 最近的工作强调了肌肉重建的作用，该作用是在肌肉发达的重新密封后进行的，其中包括 肌节大会。通过该研究计划，我们以前证明了Ferlin蛋白的作用 通过优化高分辨率实时可视化，肌膜重新密封中的附属蛋白。我们也是 开发了新型的遗传工具，以阐明这些蛋白质在膜事件中的相互作用。我们现在 提议研究重新密封蛋白在AIM 1中与富含肌动蛋白的区域相互作用中的作用。 AIM 2，我们将检查肌肉修复过程中重新密封和重建的分子和暂时重叠。 AIM 3，我们将使用生物活性脱细胞矩阵来定义和探测细胞外的作用 控制细胞对健康和疾病肌肉修复的贡献方面的附属素。这项工作的结果 将发现新的蛋白质细胞相互作用，以指导促进肌肉修复的药理学。