Kinetics of Cardiac Myofilament Activation

心肌丝激活动力学

• 批准号: 8450107
• 负责人: WEN-JI DONG
• 金额: $ 34.73万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8450107
• 关键词: Actins; Address; Affect; Binding; Cardiac; Cardiac Muscle Contraction; Cardiomyopathies; Depressed mood; Development; Diagnosis; Disease; Dissociation; Energy Transfer; Environment; Fluorescence Anisotropy; Fluorescence Spectroscopy; Goals; Head; Health; Heart; Heart failure; Human; Kinetics; Knowledge; Measurement; Measures; Mechanics; Methodology; Microfilaments; Molecular; Monitor; Muscle; Muscle Cells; Muscle Fibers; Muscle function; Muscle relaxation phase; Mutagenesis; Mutation; Myocardium; Myofibrils; Myosin ATPase; Nucleic Acid Regulatory Sequences; Outcome; Phosphorylation; Play; Preparation; Prevention; Process; Progress Reports; Proteins; Recombinant Proteins; Regulation; Relaxation; Research; Role; Sarcomeres; Series; Signal Transduction; Skin; Structural Protein; Structure; Techniques; Testing; Thick Filament; Thin Filament; Troponin; Troponin C; Troponin I; Work; base; heart function; improved; innovation; interdisciplinary approach; novel; novel strategies; prevent; protein protein interaction; public health relevance; reconstitution; response; transmission process

DESCRIPTION (provided by applicant): Heart failure can be a result of impaired cardiac contraction or relaxation or both, which are regulated by Ca2+induced thin filament activation and deactivation. Therefore, understanding the mechanism of thin filament regulation is of great importance in prevention and treatment of heart failure. The molecular basis of the thin filament regulation involves Ca2+induced alterations in the structure and structural kinetics and dynamics associated with the protein-protein interactions at the interface between troponin and actin. The objective of this proposal is to define the detailed kinetic mechanism that underlies Ca2+induced thin filament activation/deactivation and how it is affected by troponin phosphorylation and cardiomyopathy mutations found in cTnI. To achieve the goal, this proposal will address the following questions: 1) What is the kinetic role of different functional regions of cTnI in regulating crossbridge kinetics? 2) How do the structural dynamics of the cTnI C-domain play roles in thin filament regulation? and 3) How are the structural changes and structural kinetics of the thin filament modified in the skinned muscle fibers and myofibrils? The underlying hypothesis of this proposal is that the Ca2+induced structural transitions involving the different regions of troponin I at the interface between troponin and actin play different roles in regulating kinetics of the interaction between actin and mysoin, and the structural transitions can be affected by strong crossbridges, cardiomyopathy mutations, and phosphorylation of troponin proteins, as well as cellular lattice environment found in intact muscle cells. This project capitalizes on our FRET and fluorescence anisotropy expertise in determining protein structural kinetics and dynamics to exploit a new approach by implementing FRET methodologies into muscle fibers and myofibril measurements. This will enable us to acquire the urgently needed kinetic and dynamic information associated with the Ca2+induced thin filament regulation on muscle function. The results from this study will have a positive impact by advancing our understanding of the regulatory role of cardiac thin filament in cardiac muscle contraction and relaxation in health and disease.

描述（由申请人提供）：心力衰竭可能是心脏收缩或舒张受损或两者兼而有之的结果，这受到 Ca2+ 诱导的细丝激活和失活的调节。因此，了解细丝调节机制对于心力衰竭的防治具有重要意义。细丝调节的分子基础涉及 Ca2+ 诱导的结构改变以及与肌钙蛋白和肌动蛋白之间的界面处的蛋白质-蛋白质相互作用相关的结构动力学和动力学。该提案的目的是明确 Ca2+ 诱导细丝激活/失活的详细动力学机制，以及肌钙蛋白磷酸化和 cTnI 中发现的心肌病突变如何影响它。为了实现这一目标，该提案将解决以下问题：1）cTnI 不同功能区在调节桥动力学中的动力学作用是什么？ 2) cTnI C 结构域的结构动力学如何在细丝调节中发挥作用？ 3）带皮肌纤维和肌原纤维中细丝的结构变化和结构动力学如何改变？该提议的基本假设是，Ca2+诱导的结构转变涉及肌钙蛋白和肌动蛋白之间界面肌钙蛋白 I 的不同区域，在调节肌钙蛋白和肌球蛋白之间相互作用的动力学中发挥不同的作用，并且结构转变可能受到强交叉桥、心肌病突变和肌钙蛋白磷酸化以及肌钙蛋白磷酸化的影响。 完整肌肉细胞中发现的细胞晶格环境。该项目利用我们在确定蛋白质结构动力学和动力学方面的 FRET 和荧光各向异性专业知识，通过将 FRET 方法应用于肌肉纤维和肌原纤维测量来开发新方法。这将使我们能够获得与 Ca2+ 诱导的细丝对肌肉功能调节相关的迫切需要的动力学和动态信息。这项研究的结果将通过增进我们对心脏细丝在健康和疾病中心肌收缩和舒张的调节作用的理解而产生积极影响。

项目成果

Cationic isotachophoresis separation of the biomarker cardiac troponin I from a high-abundance contaminant, serum albumin.

• DOI: 10.1002/elps.201400009
• 发表时间: 2014-07
• 期刊: ELECTROPHORESIS
• 影响因子: 2.9
• 作者: Jacroux, Thomas;Bottenus, Danny;Rieck, Bennett;Ivory, Cornelius F.;Dong, Wen-ji
• 通讯作者: Dong, Wen-ji

Förster resonance energy transfer structural kinetic studies of cardiac thin filament deactivation.

Förster 心脏细丝失活的共振能量转移结构动力学研究。

• DOI: 10.1074/jbc.m808075200
• 发表时间: 2009
• 期刊: The Journal of biological chemistry
• 作者: Xing,Jun;Jayasundar,JayantJ;Ouyang,Yexin;Dong,Wen-Ji
• 通讯作者: Dong,Wen-Ji

FRET study of the structural and kinetic effects of PKC phosphomimetic cardiac troponin T mutants on thin filament regulation.

FRET 研究 PKC 磷酸模拟心肌肌钙蛋白 T 突变体对细丝调节的结构和动力学影响。

• DOI: 10.1016/j.abb.2014.03.013
• 发表时间: 2014
• 期刊: Archives of biochemistry and biophysics
• 影响因子: 3.9
• 作者: Schlecht,William;Zhou,Zhiqun;Li,King-Lun;Rieck,Daniel;Ouyang,Yexin;Dong,Wen-Ji
• 通讯作者: Dong,Wen-Ji

Preconcentration and detection of the phosphorylated forms of cardiac troponin I in a cascade microchip by cationic isotachophoresis.

• DOI: 10.1039/c1lc20469f
• 发表时间: 2011-11-21
• 期刊: Lab on a chip
• 影响因子: 6.1
• 作者: Bottenus D;Hossan MR;Ouyang Y;Dong WJ;Dutta P;Ivory CF
• 通讯作者: Ivory CF

Enzymatic amplification of DNA/RNA hybrid molecular beacon signaling in nucleic acid detection.

• DOI: 10.1016/j.ab.2012.09.015
• 发表时间: 2013-01-15
• 期刊: Analytical biochemistry
• 影响因子: 2.9
• 作者: Jacroux T;Rieck DC;Cui R;Ouyang Y;Dong WJ
• 通讯作者: Dong WJ