Invitrogen™ Phospho-ATM (Ser1981) Recombinant Rabbit Monoclonal Antibody (JM93-25)

Ataxia-telangiectasia Mutated (ATM) is a protein that belongs to the PI3/PI4 kinase family. Ataxia-telangiectasia is a rare autosomal recessive disorder characterized by progressive neurologic degeneration, immunologic deficiency, and an increased risk of lymphoid cancer. The ATM gene codes for a protein belonging to the phosphoinositide 3-kinase (PI3K) superfamily. ATM phosphorylates proteins instead of lipid and has many downstream targets that act as cell-cycle regulators including: P53, Mdm2, BRCA1, and SMC1. The ATM protein is responsible for repairing double-stranded DNA breaks that occur because of ionizing radiation and other mutagens. The ATM's C-terminal region has extensive homology to the catalytic domains of phosphatidylinositol 3-kinases (PI3 kinases). Studies have shown that ATM becomes autophosphorylated and upregulated by exposure to ionizing radiation. AT cells are hypersensitive to ionizing radiation, impaired in mediating the inhibition of DNA synthesis and display delays in p53 induction. Further, DNA damage caused by ionizing irradiation activates ATM-kinase, leading to a cascade of kinase reactions that regulate cell cycle, apoptosis, and DNA damage repair. Studies have linked ATM to apoptosis along with Nbs1 and Chk2 in the E2F1 pathway.