Evidence for novel phosphorylation sites in the central C4-C5 domains of murine cardiac myosin binding protein C

Cardiac myosin binding protein C (cMyBPC) is a key multi-domain protein in myosin cross bridge formation and cardiac contractility. It is principally regulated by phosphorylation of the residues within the M-domain in the N-terminus, which is essential for proper function. In fact, cardiac hypertrophy and heart failure have been associated with reduced overall cMyBPC phosphorylation levels. However, not much is known about the phosphorylation landscape of the enigmatic central C4-C5 domains of cMyBPC.