Mutations in cardiac myosin binding protein-C (cMyBP-C) lead to sudden death in young individuals with Familial Hypertrophic Cardiomyopathy. Despite Its clinical importance and its association with the actomyosin molecular motor of the heart, a significant gap still remains in understanding how cMyBP-C modulates cardiac power production. In addition, cMyBP-C is phosphorylated following p-adrenergic stimulation, suggesting that cMyBP-C Itself may be regulated in a phosphorylation-dependent manner. This Program Project (3 projects and 3 cores) will provide a comprehensive molecular understanding of cMyBP-C function, its regulation by phosphorylation, and its impact on cardiac contractility. Using state-ofthe- art techniques, we will characterize cMyBP-C's structure and function through studies ranging from the mechanics of the whole heart down to interactions between a single cMyBP-C molecule and the actomyosin molecular motor. Project #1 will use high resolution 3-dimensional electron microscopic reconstruction to characterize the structure of cMyBP-C and its sarcomeric organization, providing insight to its functional capacity. Project #2 will use the laser trap to assess cMyBP-C's ability to modulate actomyosin power production at the single molecule level, while Project #3 will use transgenic mouse models to define the role of cMyBP-C's putative actin-binding and its phosphorylation on cardiac function under various physiological conditions. The Ventricular and Cardiac Fiber Characterization and Integration Core (Core B) will gather the ventricular performance and fiber mechanical data to bridge the physiological gap between the single molecule and whole animal studies. In addition, the Core will provide a modeling platform to integrate the data from all physiological levels into a mechanistic model of cMyBP-C functionality. The Mouse and cMyBP-C Protein Production Core (Core C) will generate mice with mutant cMyBP-C and in vitro expression of mutant cMyBP-C protein at its actin-binding and phosphorylation domains. These hearts and protein will be studied at all anatomical levels by the various projects. The Program Project's long term goals are to: 1) define cMyBP-C's molecular structure and sarcomeric organization;2) determine how cMyBP-C modulates cardiac function in a phosphorylation-dependent manner;3) define why alterations in cMyBP-C phosphorylation are associated with heart failure in humans.

Public Health Relevance

Pumping of the heart Is generated by Interactions between thin and thick, contractile protein filaments within cardiac muscle. Cardiac myosin-binding protein-C (cMyBP-C) is a thick filament component that modulates cardiac contraction. Genetic defects in cMyBP-C result in heart failure and sudden death.:: Gaps in our understanding of cMyBP-C functionality still remain. This PPG will define cMyBP-C's molecular structure function, and regulation focusing on cMyBP-C as a target for therapeutic intervention.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Program Projects (P01)
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Heart, Lung, and Blood Initial Review Group (HLBP)
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Wang, Lan-Hsiang
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University of Vermont & St Agric College
Schools of Medicine
United States
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Lee, Kyounghwan; Harris, Samantha P; Sadayappan, Sakthivel et al. (2015) Orientation of myosin binding protein C in the cardiac muscle sarcomere determined by domain-specific immuno-EM. J Mol Biol 427:274-86
Sandri, Marco; Robbins, Jeffrey (2014) Proteotoxicity: an underappreciated pathology in cardiac disease. J Mol Cell Cardiol 71:3-10
Rainer, Peter P; Hao, Scarlett; Vanhoutte, Davy et al. (2014) Cardiomyocyte-specific transforming growth factor ? suppression blocks neutrophil infiltration, augments multiple cytoprotective cascades, and reduces early mortality after myocardial infarction. Circ Res 114:1246-57
Gupta, Manish K; Robbins, Jeffrey (2014) Post-translational control of cardiac hemodynamics through myosin binding protein C. Pflugers Arch 466:231-6
Seo, Kinya; Rainer, Peter P; Shalkey Hahn, Virginia et al. (2014) Combined TRPC3 and TRPC6 blockade by selective small-molecule or genetic deletion inhibits pathological cardiac hypertrophy. Proc Natl Acad Sci U S A 111:1551-6
Mun, Ji Young; Previs, Michael J; Yu, Hope Y et al. (2014) Myosin-binding protein C displaces tropomyosin to activate cardiac thin filaments and governs their speed by an independent mechanism. Proc Natl Acad Sci U S A 111:2170-5
Yang, Shixin; Barbu-Tudoran, Lucian; Orzechowski, Marek et al. (2014) Three-dimensional organization of troponin on cardiac muscle thin filaments in the relaxed state. Biophys J 106:855-64
Craig, Roger; Lee, Kyoung Hwan; Mun, Ji Young et al. (2014) Structure, sarcomeric organization, and thin filament binding of cardiac myosin-binding protein-C. Pflugers Arch 466:425-31
Tanner, Bertrand C W; Wang, Yuan; Robbins, Jeffrey et al. (2014) Kinetics of cardiac myosin isoforms in mouse myocardium are affected differently by presence of myosin binding protein-C. J Muscle Res Cell Motil 35:267-78
Wang, Xuejun; Robbins, Jeffrey (2014) Proteasomal and lysosomal protein degradation and heart disease. J Mol Cell Cardiol 71:16-24

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