Anti-ATM (phospho S1981) Antibody - Identical to Abcam (ab194865)

This rabbit polyclonal IgG antibody selectively recognizes the Ataxia-Telangiectasia Mutated (ATM) kinase only when phosphorylated at serine 1981, the autophosphorylation site that marks ATM activation. Raised in rabbit and supplied as an unconjugated 50 µl vial, the reagent is validated for Western blot and immunohistochemistry on human samples and is provided by Antibodies.com as a primary antibody for DNA damage response research.

ATM is a serine/threonine kinase central to the cellular response to DNA double-strand breaks. Autophosphorylation at S1981 converts ATM from an inactive dimer into an active monomer that phosphorylates downstream effectors including p53, Chk2, and H2AX, driving cell cycle arrest and DNA repair. Detecting the S1981 phospho-epitope therefore provides a direct read-out of ATM pathway activation following genotoxic stress, ionizing radiation, or treatment with DNA-damaging agents.

Practical features include a polyclonal rabbit host, IgG isotype, unconjugated format suitable for standard secondary antibody detection systems, and reactivity confirmed against human antigen. The antibody is supplied at 50 µl and is intended for research use only in studies of genome stability, cancer biology, and the DNA damage checkpoint.