Non-muscle myosin IIA heavy chain (NMHC IIA)

Non-muscle myosin IIA heavy chain (abbreviated NMHC IIA, encoded by the MYH9 gene) is a molecular motor protein that generates contractile force in most non-muscle cells. It forms a hexameric complex composed of two heavy chains, two regulatory light chains, and two essential light chains. NMHC IIA utilizes ATP hydrolysis to produce force and movement along actin filaments, performing critical roles in cytokinesis, cell migration, polarization, adhesion, maintenance of cell shape, and various developmental processes[1][2][3][4][5]. Mutations in this protein cause MYH9-related disease, a group of inherited disorders characterized by macrothrombocytopenia, nephropathy, sensorineural deafness, and cataracts, and NMHC IIA dysfunction has also been linked to chronic kidney disease and cancer[3]. The NMHC IIA protein is regulated by phosphorylation of both its light and heavy chains, as well as by interactions with several cellular partner proteins. Its function as a central cytoskeletal motor makes it essential for normal cellular and tissue physiology[1][2][5].

Other names

Myosin-9MYH9Non-muscle myosin heavy chain IIANMMHC-IIAMyosin, heavy chain 9, non-muscleNonmuscle Myosin Type IIA

Inhibition or modification of actin-myosin contractility (reported mechanism for small molecules or experimental agents, but no approved drugs target NMHC IIA directly[3])