KINETICS OF THE MUSCLE CONTRACTILE APPARATUS

肌肉收缩装置的动力学

• 批准号: 2712431
• 负责人: YALE E GOLDMAN
• 金额: $ 25.91万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1980
• 资助国家: 美国
• 起止时间: 1980-04-01 至 2002-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2712431
• 关键词: Anura; adenosine triphosphate; alternatives to animals in research; bioenergetics; biomechanics; cell motility; clathrate; laboratory rabbit; microspectrophotometry; muscle contraction; muscle disorders; muscle metabolism; muscle proteins; myofibrils; myosins; photolysis; striated muscles

The overall aims of this research are to understand the molecular mechanism by which muscle proteins convert chemical energy into mechanical work, and to obtain a precise correlation between the physiological, biochemical and structural events of muscular contraction. Novel methods will be applied to striated muscle fibers to probe the relations between biochemical reactions of the contractile proteins, the elementary mechanical steps of the cross-bridge cycle and the corresponding structural motions. Rapid changes in the chemical concentrations of pertinent biochemical species, such as ATP, will be made by laser pulse photolysis of photolabile "caged" precursors. A newly developed method to secure the fiber ends will be used to improve the uniformity and reproducibility of the contractions. The orientation of fluorescent molecules covalently bound to the myosin heads will be monitored at high time resolution to determine the rates and identity of specific structural changes of the protein molecules. This method combined with laser photolysis, new chromophoric probes, and additional labelling sites made available by recombinant technology will provide orientation and mobility information from several regions of the myosin head. The experiments will be carried out on single muscle fibers of rabbit psoas and frog semitendinosus muscles. Results from this project should significantly advance knowledge of the contractile process and thus bring a greater understanding of both normal and pathological states of striated muscle and other types of cell motility.

这项研究的总体目标是了解分子 肌肉蛋白质将化学能转化为 机械工作，并获得精确的相关性， 肌肉的生理、生化和结构事件 收缩。新的方法将应用于横纹肌纤维， 探讨心肌收缩功能的生化反应之间的关系 蛋白质，跨桥循环的基本机械步骤， 相应的结构运动。化学物质的快速变化 相关生物化学物质的浓度，如ATP，将被 通过对光不稳定的“笼状”前体的激光脉冲光解制备。一 一种新开发的固定光纤端部的方法将用于改善 收缩的均匀性和再现性。的取向 与肌球蛋白头部共价结合的荧光分子将 以高时间分辨率监测，以确定 蛋白质分子的特定结构变化。该方法 结合激光光解，新的发色探针，以及额外的 通过重组技术提供的标记位点将提供 来自肌球蛋白多个区域的方向和流动性信息 头实验将在以下的单个肌纤维上进行： 兔腰肌和青蛙半腱肌。本项目的成果 应该大大推进收缩过程的知识， 从而更好地理解正常和病理 横纹肌和其他类型细胞运动的状态。