Protein phosphatase 1 regulatory subunit 12B (PPP1R12B)

Protein phosphatase 1 regulatory subunit 12B (PPP1R12B), also known as MYPT2, is a regulatory subunit of myosin light chain phosphatase (MLCP) complex, predominantly expressed in cardiac and skeletal muscle. MYPT2 directs protein phosphatase 1 catalytic subunit beta (PP1cβ) to dephosphorylate regulatory light chains of myosin II, thereby modulating myosin activity and fine-tuning muscle contraction and the Ca^2+ sensitivity of the contractile apparatus. It is distinct from the ubiquitous MYPT1 and has specialized roles in the heart, influencing baseline cardiac function and the heart's adaptive response to hemodynamic load. Knockout and functional studies in mice have implicated MYPT2 in the regulation of cardiac hypertrophy and contractile reserve[1][2][3][4]. There are no drugs currently targeted directly to PPP1R12B, but its central role in cardiac muscle signaling positions it as a potential contributory factor in cardiac diseases and a theoretical pharmacological target for disorders of cardiac contractility.

Other names

MYPT2Myosin phosphatase target subunit 2Myosin phosphatase-targeting subunit 2PP1bp55Protein phosphatase 1, regulatory subunit 12BMyosin phosphatase regulatory subunitM20 subunitProtein phosphatase 1 regulatory subunit 12B, myosin phosphatase target subunit 2

Does not appear to be a direct drug target as of current knowledge, but theoretically, drugs modulating its activity would alter cardiac muscle phosphatase activity and thus contractility via RLC phosphorylation