FIGURE 2.

Cardiomyocyte signaling pathways converging on titin. The schematic shows the domain architecture of cardiac titin isoforms (N2B and N2BA) and binding partners that link titin to hypertrophic signaling pathways or protein quality control mechanisms. The inset demonstrates that titin-based PT can be variably tuned either by reversible phosphorylation or by altering the N2BA/N2B titin isoform expression ratio. AC, adenylyl cyclase; ANP, atrial natriuretic peptide; AngII, angiotensin II; βAR, β-adrenergic receptor; BNP, brain natriuretic peptide; CNP, C-type natriuretic peptide; ET-1, endothelin-1; G, small G-protein; GPCR, G-protein-coupled receptor; MLP, muscle LIM protein; NFAT, nuclear factor of activated T-cells; P, titin phosphorylation site; pGC, particulate guanylyl cyclase; PLC, phospholipase C; sGC, soluble guanylyl cyclase; us, unique sequence of the cardiac N2-B region.