CHEMISTRY OF MUSCLE PROTEINS

我们研究的一个主要目的是发现低分子量 肌球蛋白亚基。 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。 一个人假设 它们可能参与基本的肌动球蛋白相互作用，但不太牢固。 有证据支持这一假设。 我们将采取两项主要措施， 方向推进这个问题：（1）我们将尝试本地化的两个 通过引入特异性标记，例如 作为荧光探针或单克隆抗体进入光上的限定位点 和重链亚基。 荧光团之间的距离将通过 福斯特能量转移。 抗体-肌球蛋白复合物将通过电子 阴影投射制备的显微镜。 (2)我们将比较功能和 肌球蛋白的几种同工酶的结构特性，其中包括快和慢 肌球蛋白，来自几个发育阶段的胚胎肌球蛋白，以及合成的 通过结合慢肌球蛋白和快肌球蛋白的亚基而形成的杂交体。 技术 将包括动力学分析，二维肽图谱， 共同序列的免疫学鉴定。 通过研究这些肌球蛋白 在单体和丝状状态下的多晶型物，我们希望获得 肌球蛋白分子如何工作，以及为什么肌肉 由不同纤维类型的马赛克组成。

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.