Physical-Chemical Basis of the Contractile Mechanism

收缩机制的物理化学基础

• 批准号: 9119570
• 负责人: Susan Lowey
• 金额: $ 22.8万
• 依托单位: Brandeis University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-03-15 至 1995-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9119570&HistoricalAwards=false
• 关键词: Physical; Chemical; Basis; Contractile; Mechanism

Force is developed in muscle contraction by myosin molecule pulling actin filaments during shortening. The details of this process have been difficult to establish because of the rapid and unsynchronized nature of the many changes taking place during the relative sliding of the filaments. Our work is focused on the structural changes that are thought to be occurring in the head region of myosin during this interaction. The introduction of molecular biological techniques in recent years has permitted us to modify the polypeptide structure of myosin in such a way that reporter groups can be more readily introduced into the molecule. These groups can be fluorescent probes for spectroscopic studies, or electron dense probes for direct visualization by electron microscopy. These methods should provide new information about the dynamics of myosin crossbridge movement during ATP hydrolysis and actin binding, both in individual molecules and in muscle fibers during muscle contraction.

肌肉收缩时，肌球蛋白分子在缩短过程中拉动肌动蛋白丝，从而产生力量。由于细丝相对滑动过程中发生的许多变化具有快速且不同步的性质，因此很难确定该过程的细节。我们的工作重点是在这种相互作用过程中肌球蛋白头部区域发生的结构变化。近年来分子生物学技术的引入使我们能够修饰肌球蛋白的多肽结构，从而更容易地将报告基团引入分子中。这些基团可以是用于光谱研究的荧光探针，也可以是用于通过电子显微镜直接观察的电子致密探针。这些方法应该提供有关 ATP 水解和肌动蛋白结合过程中肌球蛋白横桥运动动力学的新信息，无论是在肌肉收缩过程中的单个分子还是肌纤维中。