DYNAMIC EVENTS IN MYOSIN DURING CONTRACTION OF MUSCLE

所有肌肉收缩模型和理论的中心特征是 肌球蛋白跨桥运动。 我们建议调查 这一运动的性质，特别是DTNB光的参与， 链和电荷相互作用在调节的处置 十字桥 在这些研究中，我们将比较磷酸化和 使用蛋白水解双酶和交联的非磷酸化肌球蛋白 方法. DTNB轻链在肌球蛋白上的精确位置仍然不确定， 尽管它们似乎桥接分子的S-1和S-2片段。 我们 计划测试轻链和抗体之间可能的直接相互作用。 肌球蛋白的S-2区。 分离和纯化的S-2片段将与 DTNB轻链在各种实验条件下的变化及其 结合相互作用将通过光谱和流体动力学技术监测。 将研究肌细胞粗丝的形成 使用新发现的肌球蛋白微丝。 微丝可以生长 变成粗丝。 这些研究将联合收割机电子显微镜与 流体动力学技术 为了更好地了解肌球蛋白的活性部位，我们将 康廷我们尝试亲和标记ATP位点（使用 p-%-氟磺酰基苯甲酰基腺苷），并将研究“捕获”和 从核苷酸位点释放“捕获的”ADP。

A central feature in all models and theories of muscle contraction is the movement of myosin cross-bridges. We propose to investigate the extent and the nature of this movement, and in particular, the involvement of the DTNB light chains and charge interactions in regulating the disposition of the cross-bridges. In these studies we will compare phosphorylated and unphosphorylated myosin employing proteolytic digestions and crosslinking methods. The precise location of the DTNB light chains on myosin is still uncertain, although they appear to bridge the S-1 and S-2 fragments of the molecule. We plan to test the possible direct interaction between the light chains and the S-2 region of myosin. Isolated and purified S-2 fragments will be combined with the DTNB light chains under a variety of experimental conditions and their binding interaction will be monitored by spectral and hydrodynamic techniques. The formation of the thick filaments of the muscle cell will be studied employing the newly discovered myosin minifilaments. The minifilaments can grow into thick filaments. These studies will combine electron microscopy with hydrodynamic techniques. In order to develop a better understanding of the active site of myosin we will contine our attempts to affinity label the ATP site (using p-%-fluorosulfonylbenzoyladenosine) and will investigate the "trapping" and the release of the "trapped" ADP from the nucleotide site.