Cardiac myosin binding protein-C: a structurally dynamic regulator of myocardial contractility.
Cardiac myosin binding protein-C (cMyBP-C) is a modular protein anchored to the thick filament through interactions mediated by its C-terminal region. The N-terminal region of cMyBPC-C regulates myocardial contractility by modifying actin-myosin association. Phosphorylation of the N-terminal region diminishes cMyBP-C's capacity to regulate actin-myosin function. Despite a substantial body of literature, many issues remain unclear regarding the structural and functional roles of cMyBP-C. While no high-resolution structures of the intact protein exist, crystallographic and nuclear magnetic resonance (NMR) structures of isolated N-terminal domains provide important molecular details regarding cMyBP-C's role in controlling contractility. In this review, we summarize the emerging structural understanding of cMyBP-C with a particular emphasis placed on describing how its dynamic molecular interactions with both thin and thick filament proteins likely contribute to contractile regulation. Furthermore, we discuss the future directions and strategies by which we may improve the mechanistic understanding of its role in modulating cardiac muscle contraction.
The Cell, Molecular, and Structural Biology Program, Department of Microbiology, Miami University, 700 East High Street, 32 Pearson Hall, Oxford, OH, 45056, USA, finleynl@miamioh.edu.
Natosha L
NL
Finley
Tzvia I
TI
Cuperman
D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D009200:Myocardial Contraction; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D000099163:Myosin Binding Protein C
D000199:Actins; D002352:Carrier Proteins; D000099163:Myosin Binding Protein C