CHEMISTRY OF MUSCLE PROTEINS

我们研究的一个主要目的是发现低分子量的作用 肌球蛋白中的亚基。经过几个实验室近十年的努力， 它们在脊椎动物骨骼肌中的功能仍然不清楚。有人认为 它们可能参与了肌动球蛋白的基本相互作用，但并不牢固 有证据支持这一假设。我们将追求两个主要目标 推进这一问题的方向：(1)我们将尝试将两者本地化 肌球蛋白头部轻链的分类通过引入特定的标记，如 作为荧光探针或单抗进入光线上的特定位置 和重链亚基。荧光团之间的距离将通过以下方式测量 福斯特能量转移。抗体-肌球蛋白复合体将用电子手段观察 阴影投射制剂的显微镜检查。(2)我们将比较功能和 肌球蛋白几种同工酶的结构性质，其中包括快和慢 肌球蛋白，几个发育阶段的胚胎肌球蛋白，以及合成的 由慢速和快速肌球蛋白亚基结合而成的杂交体。技术 将包括动力学分析、二维肽图和 常见序列的免疫学鉴定。通过研究这些肌球蛋白 无论是单体状态还是丝状状态，我们都希望获得 对肌球蛋白分子如何工作以及肌肉为什么 由这种不同纤维类型的马赛克组成的。

A major aim in our research is to discover the role of the low molecular weight subunits in myosin. After nearly a decade of effort by several laboratories, their function in vertebrate skeletal muscle remains obscure. One assumes that they are probably involved in the basic actomyosin interaction, but little firm evidence is available to support this hypothesis. We will pursue two main directions to advance this problem: (1) We will attempt to localize the two classes of light chains in the myosin head by introducing specific markers, such as fluorescent probes or monoclonal antibodies into defined sites on the light and heavy chain subunits. Distances between fluorophores will be measured by Forster energy transfer. Antibody-myosin complexes will be viewed by electron microscopy of shadow-cast preparations. (2) We will compare the functional and structural properties of several isoenzymes of myosin, among them fast and slow myosins, embryonic myosin from several stages of development, and synthetic hybrids formed by combining the subunits of slow and fast myosins. Techniques will include kinetic analysis, two-dimensional peptide mapping, and immunological identification of common sequences. By studying these myosin polymorphs both in the monomeric and filamentous state, we hope to gain additional insights into how the myosin molecule works, and why muscle is composed of such a mosaic of different fiber types.