Role of Obscurin and Obscurin-MLCK in myofibrillogenesis

Obscurin 和 Obscurin-MLCK 在肌原纤维形成中的作用

• 批准号: 7021382
• 负责人: Mark W Russell
• 金额: $ 29.36万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-03-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7021382
• 关键词: alternatives to animals in research; ankyrins; cardiac myocytes; cardiogenesis; chick embryo; congestive heart failure; electrophysiology; gene targeting; genetically modified animals; guanine nucleotide exchange factors; heart function; intermolecular interaction; laboratory mouse; laboratory rat; molecular pathology; muscle cells; muscle proteins; myocardial ischemia /hypoxia; myofibrils; myogenesis; myosin light chain kinase; nonmammalian vertebrate embryology; phosphorylation; protein structure function; sarcomeres; striated muscles; tissue /cell culture; zebrafish

DESCRIPTION (provided by applicant): During development, during hypertrophic growth and in response to injury, the heart undergoes profound remodeling at both the tissue and cellular level. Defects in the assembly and integration of new myofibrils can lead to myofibril disarray, myocyte death, and congestive heart failure. Obscurin is a novel giant sarcomeric protein links the sarcomere to the sarcoplasmic membrane through interactions with titin and ankyrin. As such, it may have vital roles in myofibril assembly and in proper positioning of ankyrin-associated ion channels relative to the contractile apparatus. The specific aims of this study will therefore be to 1) examine the effects of antisense morpholino-mediated obscurin inhibition on in vivo myofibril assembly and cardiac and skeletal muscle development in zebrafish embryos using immunohistochemical analysis and videographic assessment of cardiac function 2) characterize physical interactions between obscurin and other sarcomeric proteins using yeast two hybrid and in vitro binding studies, and determine their physiologic significance through competitve inhibition of the interaction in beating cardiac myocytes in culture 3) determine if the ankyrin-obscurin interaction is disrupted by pathologic processes such as chronic arrhythmia (using a canine model of atrial fibrillation) or hypoxia (in cultured cardiac myocytes) and examine the potential role of ankyrin and/or obscurin phosphorylation in regulating the interaction 4) using conditional gene targeting to inhibit the obscurin Rho guanine nucleotide exchange factor (RhoGEF) signaling in a tissue- and stage-specific manner in mice, determine its specific contributions to myofibril assembly during adaptive cardiac hypertrophy (secondary to aortic constriction) and skeletal muscle repair. Characterizing obscurin's roles in new myofibril assembly and in sarcomere-sarcoplasma organization may identify new strategies to treat congestive heart failure and prevent myofibril damage during ischemia.

描述（由申请人提供）：在发育期间，在肥厚性生长过程中以及对损伤的响应中，心脏在组织和细胞水平上都经历了深刻的重塑。 新肌原纤维组装和整合的缺陷会导致肌原纤维混乱，肌细胞死亡和充血性心力衰竭。 Sigburin是一种新型的巨型肉瘤蛋白，通过与钛和脚踝蛋白的相互作用，将肌膜连接到肌质膜。 因此，它可能在肌纤维组件和相对于收缩仪的适当定位脚踝相关离子通道中具有至关重要的作用。 因此，这项研究的具体目的将是1）检查反义吗啡介导的梅型抑制对体内肌原纤维组装的影响，以及通过免疫组织化学分析和视频评估的斑布蛋白质和其他肉体蛋白质之间的纽约蛋白质和其他研究的效果，并确定Y型肌动蛋白之间的Y型蛋白质，并在斑马鱼胚胎中发育中的心脏和骨骼肌发育效果2）通过竞争性抑制培养中心肌细胞相互作用的竞争性抑制，生理意义 3）确定arnkyrin-obscurin的相互作用是否受到病理学过程的破坏，例如慢性心律失常（使用心房颤动的犬模型）或缺氧（在培养的心肌细胞中）并检查脚踝蛋白和/或掩盖磷酸盐磷酸化的潜在作用 4）使用条件基因靶向在小鼠中抑制组织和阶段特异性方式中的近距离鸟嘌呤核苷酸交换因子（Rhogef）信号传导，确定其在自适应心脏肥大期间对肌原纤维组装的特异性贡献（次要性主动脉约束）和骨骼肌肉修复。 表征黑素在新的肌原纤维组装中的作用以及在肉瘤 - 萨科群岛组织中的作用，可以确定新的策略来治疗充血性心力衰竭并防止缺血期间肌膜纤维损害。