Background
ATM belongs to a family of proteins, conserved from yeast to humans that regulate cell-cycle checkpoints and are involved in DNA repair and recombination. The protein has a carboxy-terminal sequence with significant homology to the catalytic domain of phosphatidylinositol-3-OH kinase. In response to DNA damage agents such as ionizing irradiation and chemical agent cisplatin, ATM kinase is activated, leading to a cascade of kinase reactions regulating cell cycle, apoptosis, and DNA damage repair . Besides it also regulates radiation sensitivity, and cellular proliferation. Many downstream target molecules of ATM kinase were so far identified. These target proteins include p53/TP53, FANCD2, NFKBIA, BRCA1, CTIP, nibrin (NBN), TERF1, RAD9 and DCLRE1C. Mutations in the gene contribute to human cancer-associated diseases ataxia-telangiectasia, T-cell acute lymphoblastic leukemia, B-cell non-Hodgkin lymphomas and B-cell chronic lymphocytic leukemia. Human ATM gene is located on chromosome 11q22-23. |
