PROXIMITY RELATIONSHIPS AMONG MUSCLE PROTEINS

该项目的长期目标是阐明 1)骨骼肌收缩过程中的能量传递；2)骨骼肌收缩时的 钙离子对骨骼肌收缩的调节作用。因为这两个人 过程是正常肌肉组织功能的基础，这 工作可能提供对病理性肌肉的本质的洞察 条件。这一目标将通过确定空间 四种主要收缩蛋白：肌球蛋白、肌动蛋白、 原肌球蛋白和肌钙蛋白。此外，这些空间关系是如何 随着肌肉功能状态的变化(放松、激活或 严格性)将被检查。这样得到的信息将被用来 重建肌肉收缩和收缩过程中发生的分子事件 它的规定。 主要将使用两种技术来确定空间 关系：激发、能量转移和光化学 交联剂。原肌球蛋白和三者之间的距离 肌钙蛋白的亚基将通过激发能量转移来确定 测量。同时，界面上的氨基酸残基 将利用光交联和多肽来鉴定蛋白质之间的关系 分析技术。从这些研究中获得的信息将被用于 肌钙蛋白原肌球蛋白三维模型的构建 很复杂。以类似的方式，原肌球蛋白中的位点之间的距离， 肌动蛋白和肌球蛋白之间的相互作用界面将被确定 这些蛋白质被鉴定出来。这将提供有关 肌球蛋白-放线菌素-原肌球蛋白复合体及其接触区中的原肌球蛋白 介于肌球蛋白和肌动蛋白之间。

The long-term objective of this project is to elucidate the mechanisms for 1) transduction of energy during contraction of skeletal muscle, 2) the regulation of skeletal muscle contraction by calcium ions. Since these two processes are fundamental to the functioning of normal muscle tissue, this work may provide insight into the nature of pathological muscle conditions. This objective will be achieved by determining the spatial relationships among the four major contractile proteins: myosin, actin, tropomyosin and troponin. Furthermore, how these spatial relationships change with the functional state of muscle (relaxed, activated, or in rigor) will be examined. Information so derived will be used to reconstruct the molecular events that occur during muscle contraction and its regulation. Principally, two techniques will be used to determine spatial relationships: excitation energy transfer, and photochemical crosslinking. The distances between sites in tropomyosin and in the three subunits of troponin will be determined by excitation energy transfer measurements. Simultaneously, amino acid residues at the interfaces between the proteins will be identified using photocrosslinking and peptide analysis techniques. Information derived from these studies will be used to construct a three-dimensional model for the troponin.tropomyosin complex. In a similar fashion, distances between sites in tropomyosin, actin and myosin will be determined, and the interaction interfaces between these proteins identified. This will yield information on the location of tropomyosin in the myosin.actin.tropomyosin complex, and the contact region between myosin and actin.