CROSS BRIDGE KINETICS AND REGULATION

跨桥动力学和调节

• 批准号: 6564808
• 负责人: Avril V. Somlyo
• 金额: $ 39.96万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6564808
• 关键词: G protein; adenosine diphosphate; adenosine triphosphate; biological signal transduction; calcium flux; clathrate; confocal scanning microscopy; creatine phosphate; crosslink; enzyme activity; enzyme mechanism; fluorescent dye /probe; hydrolysis; laboratory mouse; laboratory rabbit; molecular biology; muscle contraction; myosin light chain kinase; myosins; phosphatase inhibitor; phosphorylation; protein isoforms; protein kinase C; smooth muscle; vascular smooth muscle; vasomotion

Vascular smooth muscle is an essential regulator of the distribution of blood flow and its abnormalities contribute to high blood pressure, atherosclerosis, coronary restenosis and shock. Other smooth muscles play similarly important roles and regulate airway function and gastrointestinal, uterine and bladder movements. This project will determine the regulations and kinetics of crossbridge cycling, the fundamental mechanism of contraction of all smooth muscles, determines the kinetics of crossbridge cycling, and its structural basis is the variable, smooth muscle-specific expression of essential light chain and heavy chain myosin isoforms. Functional studies will be conducted on smooth muscles containing, respectively, myosins with or without the heavy chain insert and selectively modified by targeted expression or exchange of light chain isoforms. The off-rates of ADP and inorganic phosphate from crossbridges will be determined with novel fluorescent probes developed by The Core, and will be related to the rates of force development and shortening velocity. We will identify the kinases, phosphates and other proteins involved in fine-tuning the balance between myosin light chain kinase and phosphatase activities (collaboration with T. Haystead) and determine the physiological role of the phosphatase- regulating protein, telokin, through functional studies of mouse models deficient (knockout) or subjected to targeted over-expression of this protein (collaboration with G. Owens).

血管平滑肌是血流分布及其异常的必要调节剂，有助于高血压，动脉粥样硬化，冠状动脉再狭窄和休克。其他平滑肌扮演着同样重要的角色，并调节气道功能以及胃肠道，子宫和膀胱运动。该项目将确定Crossbridge自行车的法规和动力学，所有平滑肌肉收缩的基本机制，确定了Crossbridge循环的动力学，其结构基础是可变的，平滑的肌肉特异性光链链链和重链链肌蛋白质肌动蛋白的表达。功能研究将分别对含有或没有重链插入物的肌球蛋白分别进行平滑肌肉进行，并通过针对轻链同工型的靶向表达或交换来选择性地修饰。 ADP和无机磷酸盐的离率将由核心开发的新荧光探针确定，并将与力的发育速率和缩短速度有关。我们将确定与调节肌球蛋白轻链激酶和磷酸酶活性（与T. Haystead的合作）之间的平衡有关的激酶，磷酸盐和其他蛋白质，并确定磷酸酶调节蛋白的生理作用，Telokin，Telokin，通过对靶标的型蛋白质（敲除）的功能性研究（淘汰）的功能性研究（淘汰）（敲除）（淘汰）与protsed otecters的功能性研究（敲除）。