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

• 批准号: 8061931
• 负责人: STEVEN D SCHWARTZ
• 金额: $ 40.11万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-12-15 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8061931
• 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

DESCRIPTION (provided by applicant): 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 cTnT (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. PUBLIC HEALTH RELEVANCE: Familial Hypertrophic Cardiomyopathy is an often devastating and common cardiac genetic 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. This application is aimed at elucidating how this "action at a distance" causes dysfunction and eventual human disease.

描述（由申请人提供）： 家族性肥厚型心肌病是一种常见的遗传性心脏病。心脏蛋白的特定突变已被确定为这种疾病的根本原因，但它们往往发挥其生物学效应远离突变位点。这种效应通常统称为变构，是蛋白质生物化学常用词汇的一部分，我们的研究计划的实施将证明这种效应也是心脏运动的多蛋白质控制成分-细丝的一部分。特别是，我们专注于Ca 2+结合cTnT（长期以来被认为是一个跳动的心脏控制的主要组成部分，）和磷酸化在cTnI的一个已知的重要位置。事实上，我们计划研究的突变（全部在cTnT中）在某些情况下已被证明对这两种控制机制产生显著影响，这似乎证明了“远距离作用”的原则，但缺乏的是从分子水平到整个动物生理学对这些变化如何导致疾病的翻译理解。因此，以这种方式研究的复杂多部件机器中的Allostery在基础科学中具有重大影响，并且在理解毁灭性和相对常见的人类疾病的根本原因方面具有最高意义。为了解决这些问题，我们设计了一个研究策略的方法，从计算的所有原子模型的肌钙蛋白复合物，原肌球蛋白，肌动蛋白骨架，生物物理测量的野生型和突变的重构细丝的属性，纤维的研究。这些方法产生了部分互补但重叠的信息，为这一复杂问题提供了全面综合的分析。为了更好地了解这些生物控制剂在健康和疾病中的功能变构，我们将研究以下2个具体目标：具体目标1：评估Ca 2+结合原肌球蛋白运动的转导的分子机制，以及这如何调节野生型和已知FHC连锁的TNT 1突变中心脏功能的细丝控制的生物物理学和生理学。具体目标二：评价cTnI的Ser 23/24磷酸化在野生型和已知FHC相关TNT 1突变中调节肌丝激活的分子机制。 公共卫生相关性： 家族性肥厚型心肌病是一种常见的心脏遗传性疾病。心脏蛋白的特定突变已被确定为这种疾病的根本原因，但它们往往发挥其生物学效应远离突变位点。该应用旨在阐明这种“远距离作用”如何导致功能障碍并最终导致人类疾病。