NM23-H1/H2 Antibody (642825)

NM23-H1 (Non-metastatic protein 23 homolog 1; also NDKA and NME1) is a 19‑20 kDa member of the NDK family of enzymes. NM23-H1 is ubiquitous in expression, and performs multiple functions. It forms disulfide-linked homohexamers, and heterohexamers with NM23-H2, generating a nucleoside diphosphate kinase that catalyzes a phosphoryl transfer from ATP to a nucleoside diphosphate. It also shows His and Ser/Thr protein kinase activity, and forms covalent linkages with molecules diverse as p53 and STRAP. It is found both intracellularly, and in blood at ng/mL concentrations. Human NM23-H1 is 152 amino acids (aa) in length, contains one NDP kinase domain (aa 5‑134) and shows acetylation at Ala2 and Lys56, plus phosphorylation at Tyr52, Thr94, Ser122 and Ser125. Human NM23-H1 shares 89% aa identity with human 17‑18 kDa NM23-H2, and 94% aa identity with mouse NM23-H1. A second H1 isoform named NM23-H1B with 25 additional aa at the N‑terminus has also been described.