Myosin Light Chain 2 (MYL2)

Myosin regulatory light chain 2, ventricular/cardiac muscle isoform is the regulatory light chain associated with cardiac myosin beta (or slow) heavy chain. Ca+ triggers the phosphorylation of regulatory light chain that in turn triggers contraction. Mutations in MYL2 are associated with mid-left ventricular chamber type hypertrophic cardiomyopathy.The 2 pairs of light chains of muscle myosins are called essential light chains (ELC) and regulatory light chains (RLC).

The light chains stabilize the long alpha helical neck of the myosin head. Myosin light chain-2 (MYL2) is an important protein in the regulation of myosin ATPase activity in smooth muscle. An increase in ventricular MYL2 is observed in the hypertrophied myocardium of cardiac patients with valvular stenosis.