Anti-ATM antibodies are used in the immunodetection of the protein ATM serine/threonine kinase. In humans, the canonical protein has a reported length of 3056 amino acid residues and a mass of 350.7 kDa. Its subcellular localization is in the nucleus, cytoplasmic vesicles, and cytoplasm. It is notably widely expressed in many tissue types. A member of the PI3/PI4-kinase protein family, ATM is a serine/threonine protein kinase which activates checkpoint signaling upon double strand breaks (DSBs), apoptosis and genotoxic stresses such as ionizing ultraviolet A light (UVA), thereby acting as a DNA damage sensor. Post-translational modifications have been described, including acetylation and phosphorylation. The ATM gene has been associated with the disease, Ataxia telangiectasia. Synonyms for this target antigen include ATA, ATC, ATD, ATDC, ATE, TEL1, TELO1, and AT1. ATM gene orthologs have been reported in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.