A molecular study linking cTnT dynamics to genetic cardiomyopathy

将 cTnT 动力学与遗传性心肌病联系起来的分子研究

基本信息

批准号：
8386993
负责人：
STEVEN D SCHWARTZ
金额：
$ 33.28万
依托单位：
UNIVERSITY OF ARIZONA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-12-15 至 2016-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8386993
关键词：
Actins Address Animals Basic Science Binding Binding Proteins Biological Biological Process Biophysics Calcium Binding Cardiac Cardiomyopathies Cereals Chemicals Complex Cyclic AMP-Dependent Protein Kinases Disease Distant Environment Exertion Familial Hypertrophic Cardiomyopathy Fiber Functional disorder Generations Genetic Health Heart Heart Diseases Hereditary Disease In Vitro Individual Induced Mutation Lead Link Location Measurement Mediating Methodology Microfilaments Microscopic Modeling Molecular Motor Movement Muscle Muscle Fibers Muscle function Mutate Mutation Myocardium Phosphorylation Phosphorylation Site Phosphotransferases Physiological Physiology Plant Roots Play Property Protein Biochemistry Proteins Research Site Skin Structure Thin Filament Tissues Tropomyosin Troponin Troponin T Vertebral column Vocabulary cell motility disease-causing mutation human disease inorganic phosphate movie mutant programs reconstitution research study response troponin-tropomyosin complex

项目摘要

Familial Hypertrophic Cardiomyopathy is a common and often devastating genetic cardiac disease. Specific mutations in cardiac proteins have been identified as the root cause of this disease, but they often exert their biological effect far from the site of mutation. Such effects, usually known collectively as allostery are part of the common vocabulary of protein biochemistry, and implementation of our research program will demonstrate how such effects are also part of a multi-protein controlling component of the cardiac motor - the thin filament. In particular we focus on Ca2+ binding to cTnC (long known to be a major component in the control of a beating heart,) and phosphorylation at a known important location in cTnI. The fact that the mutations we plan to study (all in cTnT) have in some cases been shown to effect significant changes on both these control mechanisms seems to demonstrate the principle of "action at a distance" but what is lacking is a translational understanding of how these changes cause disease from the molecular level to whole animal physiology. Allostery in a complex multi-component machine investigated in this fashion is thus both of great impact in basic science and of the highest significance in understanding the root cause of a devastating and relatively common human disease. To address these questions we have devised a research strategy of methodologies that range from computation on an all atom model of the troponin complex, tropomyosin, and an actin backbone, to biophysical measurements of the properties of wildtype and mutated reconstituted thin filaments, to fiber studies. The methodologies yield partially complementary yet overlapping information that provides a fully integrated analysis of this complex question. In order to better understand allostery in the function of these biological control agents in both health and disease we will study the following 2 specific aims: Specific Aim 1: To evaluate the molecular mechanism of the transduction of Ca2+ binding to the movement of tropomyosin and how this regulates the biophysics and physiology of the thin filament control of cardiac function in wildtype and known FHC-linked TNT1 mutations. Specific Aim 2: To evaluate the molecular mechanism of the phosphorylation of Ser 23/24 of cTnI in regulating myofilament activation in wildtype and known FHC-linked TNT1 mutations.

家族性肥厚性心肌病是一种常见且经常毁灭性的遗传心脏疾病。心脏蛋白的特异性突变已被确定为该疾病的根本原因，但是他们经常发挥其生物学作用，远离突变部位。这种效果，通常已知作为变构是蛋白质生物化学的常见词汇的一部分，并实施我们的研究计划将证明这种效果也是多蛋白控制的一部分心电机的组成部分 - 细丝。特别是我们专注于Ca2+与CTNC结合（长期以来已知是控制心脏控制的主要组成部分），在已知的 CTNI的重要位置。在某些情况下，我们计划研究的突变（全部）都有这一事实被证明会对这两种控制机制产生重大变化似乎证明了 “距离行动”的原则，但是缺少的是对这些方式的翻译理解变化导致疾病从分子水平到整个动物生理学。在一个综合体中变构因此在理解毁灭性和相对常见的根本原因方面的意义最高人类疾病。为了解决这些问题，我们设计了一种方法论的研究策略从肌钙蛋白复合物，肌球蛋白和肌动蛋白的所有原子模型上的计算范围主链，以生物物理测量野生型的性质和突变的重构薄细丝，进行纤维研究。方法产生部分互补但重叠的信息这提供了对这个复杂问题的完全集成分析。为了更好地理解变构在这些生物控制剂在健康和疾病中的功能中，我们将研究以下2 具体目的：具体目的1：评估Ca2+结合转导的分子机制 tropomyosin的运动以及这如何调节细丝的生物物理学和生理学控制野生型和已知FHC连接的TNT1突变中心脏功能的控制。具体目的2：评估CTNI Ser 23/24磷酸化的分子机制调节野生型和已知FHC连接的TNT1突变中的肌丝激活。