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450 Rabbit

Product Usage Information

Storage: Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at –20°C. Do not aliquot the antibody.

Specificity / Sensitivity

Phospho-DNA-PK (Ser2056) Antibody recognizes endogenous levels of DNA-PK protein only when phosphorylated at Ser2056.

Species predicted to react based on 100% sequence homology: Monkey

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to residues surrounding Ser2056 of human DNA-PK protein. Antibodies are purified by protein A and peptide affinity chromatography.

DNA-dependent protein kinase (DNA-PK) is an important factor in the repair of double-stranded breaks in DNA. Cells lacking DNA-PK or in which DNA-PK is inhibited fail to show proper nonhomologous end-joining (NHEJ) (1-7). DNA-PK is composed of two DNA-binding subunits (Ku70 and Ku86) and one 450 kDa catalytic subunit (DNA-PKcs) (8). It is thought that a heterodimer of Ku70 and Ku86 binds to double-stranded DNA broken ends before DNA-PKcs binds and is activated (1,9). Activated DNA-PKcs is a serine/threonine kinase that has been shown to phosphorylate a number of proteins in vitro, including p53, transcription factors, RNA polymerase, and Ku70/Ku86 (10,11). DNA-PKcs autophosphorylation at multiple sites, including Thr2609 and Ser2056, results in an inactivation of DNA-PK kinase activity and NHEJ ability (12,13). It has been demonstrated, however, that DNA-PK preferentially phosphorylates substrates before it autophosphorylates, suggesting that DNA-PK autophosphorylation may play a role in disassembly of the DNA repair machinery (14,15). Autophosphorylation at Thr2609 has also been shown to be required for DNA-PK-mediated double strand break repair, and phosphorylated DNA-PK co-localizes with H2A.X and 53BP1 at sites of DNA damage (16). Phosphorylation at Ser2056 occurs in response to double-stranded DNA breaks and ATM activation (17).

1.  Gottlieb, T.M. and Jackson, S.P. (1993) Cell 72, 131-42.

2.  Hartley, K. O. et al. (1995) Cell 82, 840-856.

3.  Rosenzweig, K.E. et al. (1997) Clin Cancer Res 3, 1149-56.

4.  Jackson, S.P. and Jeggo, P.A. (1995) Trends Biochem Sci 20, 412-5.

5.  Roth, D.B. et al. (1995) Curr Biol 5, 496-9.

6.  Baumann, P. and West, S.C. (1998) Proc Natl Acad Sci U S A 95, 14066-70.

7.  Chen, S. et al. (2001) J Biol Chem 276, 24323-30.

8.  Jeggo, P.A. (1997) Mutat Res 384, 1-14.

9.  Suwa, A. et al. (1994) Proc Natl Acad Sci U S A 91, 6904-8.

10.  Anderson, C.W. and Lees-Miller, S.P. (1992) Crit Rev Eukaryot Gene Expr 2, 283-314.

11.  Kuhn, A. et al. (1995) Genes Dev 9, 193-203.

12.  Chan, D.W. and Lees-Miller, S.P. (1996) J Biol Chem 271, 8936-41.

13.  Douglas, P. et al. (2002) Biochem. J. 368, 243-251.

14.  Lees-Miller, S.P. et al. (1992) Mol Cell Biol 12, 5041-9.

15.  Jackson, S.P. et al. (1990) Cell 63, 155-65.

16.  Chan, D.W. et al. (2002) Genes Dev 16, 2333-8.

17.  Yajima, H. et al. (2009) J Mol Biol 385, 800-10.

Entrez-Gene Id 5591
Swiss-Prot Acc. P78527

For Research Use Only. Not For Use In Diagnostic Procedures.
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Phospho-DNA-PK (Ser2056) Antibody