Catalog # AM3661

ATM (Ser-1981), phospho-specific Antibody

Mouse Monoclonal

Application / Dilution

Size 100 μl

Species Reactivity Hu, Rt, Ms

MW 370 kDa

Isotype IgG1



Ataxia telangiectasia mutated kinase (ATM) is a serine/threonine kinase that regulates cell cycle checkpoints and DNA repair. Mutations of ATM cause a spectrum of defects ranging from neurodegeneration to cancer predisposition. Activation of ATM after DNA damage involves Cdk5 mediated phosphorylation of Ser-794 followed by autophosphorylation at Ser-1891. Active ATM kinase regulates a number of proteins involved in cell cycle checkpoint control, apoptosis and DNA repair. The Cdk5–ATM pathway regulates phosphorylation and function of the ATM targets p53 and H2AX in postmitotic neurons. Other known substrates of ATM include Chk2, Chk1, CtIP, 4E-BP1, BRCA1, RPA3, SMC1, FANCD2, Rad17, Artemis, Nbs1, and the I-2 regulatory subunit of PP1. Thus, activation of Cdk5 by DNA damage may be an important initiator of ATM-dependent regulation of cell cycle checkpoints.


Tian, B. et al. (2009) Nat Cell Biol. 11:211.
Lee, J.H. & Paull, T.T. (2007) Oncogene 26:7741.
Shiloh, Y. (1997) Annu Rev Genet. 31:635.

Western blot of human A431 cells treated with Calyculin A (100 nM) for 30 min. Blot lanes were untreated (lanes 1, 3, & 5) or treated with lambda phosphatase (lanes 2, 4, & 6) then probed with anti-ATM (Ser-794) (lanes 1 & 2), anti-ATM (C-Terminal) (lanes 3 & 4), or anti-ATM (Ser-1981) (lanes 5 & 6).

Immunocytochemical labeling of ATM phosphorylation in control (Top row) or calyculin A-treated A431 cells (Bottom row). The cells were labeled with mouse monoclonal ATM (C-terminal region) (AM3611) and ATM (Ser-1981) (AM3661). The antibodies were detected using goat anti-mouse-DyLight® 594.

Clone M366 was generated from a phospho-peptide that included amino acids surrounding Serine 1981 in human ATM. This sequence has high homology to the conserved site in rat and mouse ATM.

*For more information, see UniProt Accession Q13315
Mouse monoclonal, protein A purified antibody is supplied in 100µl phosphate-buffered saline, 50% glycerol, 1 mg/ml BSA, and 0.05% sodium azide. Store at -20°C. Stable for 1 year.

The products are are safely shipped at ambient temperature for both domestic and international shipments. Each product is guaranteed to match the specifications as indicated on the corresponding technical data sheet. Please store at -20C upon arrival for long term storage.

This antibody detects a 370 kDa* protein corresponding to the molecular mass of ATM on SDS-PAGE immunoblots of calyculin A treated human A431 and Jurkat Cells, but is not observed in control cells.

*All molecular weights (MW) are confirmed by comparison to Bio-Rad Rainbow Markers and to western blot mobilities of known proteins with similar MW.

This kit contains: