CARDIAC MYOSIN STRUCTURE/FUNCTION RELATIONSHIPS

心肌肌球蛋白结构/功能关系

• 批准号: 6241530
• 负责人: H Lee Sweeney
• 金额: $ 21.84万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6241530
• 关键词: Baculoviridae; SDS polyacrylamide gel electrophoresis; adenosinetriphosphatase; chemical kinetics; chimeric proteins; clone cells; electron microscopy; enzyme activity; gene expression; laboratory rat; muscle contraction; myocardium; myosins; protein isoforms; protein structure function; tissue /cell culture; transfection /expression vector; western blottings

This project will study structure/function relationships of mammalian cardiac myosin. Myosin is the protein that, through its interaction with actin, is the force generator of the heart. A detailed knowledge of mammalian cardiac myosin will be important in understanding the function of normal and diseased hearts. The primary goal of this study is to define the domains within the myosin heavy chain that underlie the functional differences between the alpha and beta cardiac myosin heavy chain isoforms. (This will involve the construction of alpha/beta myosin heavy chain hybrids.) Recently, it has been shown that the myosin molecule itself is defective in patients with hypertrophic cardiomyopathy. Thus in addition to delineation of basic structure/function relationships of mammalian cardiac myosin, the methodology developed in this project will also be used to understand mutations in myosin that lead to this human heart disease. In order to study cardiac myosin, we are developing two expression and functional assay systems. The first entails myosin expression in a cultured cell line derived from insects (SF9 cells) that can be infected with a virus (baculovirus) altered in the laboratory so that it will produce large amounts of mammalian cardiac myosin. This myosin will be isolated and its interactions with actin will be studied. The second approach involves the transfer of DNA that codes for cardiac myosin into cultured avian myogenic cells. The cells will remain in culture until they produce and incorporate the mammalian cardiac myosin. A single cell will then be removed from the culture dish, and its structural and contractile properties will be examined. In this manner it will be possible to document how changes in the myosin molecular alter both the structural and contractile properties of cultured muscle cells and thus the cells of the human heart.

该项目将研究哺乳动物的结构/功能关系 心脏肌球蛋白。 肌球蛋白是通过与 肌动蛋白是心脏的力量发生器。 详细了解 哺乳动物心脏肌球蛋白对于理解功能很重要 正常和患病的心。 这项研究的主要目标是 定义肌球蛋白重链中的域，这是 Alpha和β心脏肌球蛋白重量之间的功能差异 链同工型。 （这将涉及α/β肌球蛋白的构建 重链杂种。）最近，已经表明肌球蛋白 分子本身在肥厚的患者中有缺陷 心肌病。 因此，除了划定基本 哺乳动物心脏肌球蛋白的结构/功能关系， 该项目中开发的方法也将用于了解 导致这种人心脏病的肌球蛋白突变。 为了研究心脏肌球蛋白，我们正在发展两个表达，并且 功能测定系统。 第一个需要在 源自昆虫（SF9细胞）的培养细胞系，可以感染 在实验室中改变了病毒（杆状病毒），以便它 产生大量的哺乳动物心脏肌球蛋白。 这个肌球蛋白会 将研究孤立及其与肌动蛋白的相互作用。 第二个 方法涉及将心脏肌球蛋白编码为心脏肌球蛋白中的DNA转移 培养的鸟类肌原细胞。 细胞将保留在文化中，直到 它们产生并掺入哺乳动物心脏肌球蛋白。 一个单元 然后将从培养皿及其结构和 收缩性能将进行检查。 以这种方式将是 可以记录肌球蛋白分子的变化如何改变 培养的肌肉细胞的结构和收缩特性，因此 人心细胞。