Previous Article | Next Article 
Molecular and Cellular Biology, November 2005, p. 9910-9919, Vol. 25, No. 22
0270-7306/05/$08.00+0 doi:10.1128/MCB.25.22.9910-9919.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
Protein Phosphatase 5 Is Required for ATR-Mediated Checkpoint Activation
Ji Zhang,1
Shideng Bao,1,2
Ryohei Furumai,1
Katerina S. Kucera,1
Ambereen Ali,1
Nicolas M. Dean,3 and
Xiao-Fan Wang1*
Department of Pharmacology and Cancer Biology,1
Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710,2
Department of Functional Genomics, GeneTrove (Division of Isis Pharmaceuticals), Carlsbad, California 920083
Received 30 December 2004/
Returned for modification 24 January 2005/
Accepted 8 August 2005
In response to DNA damage or replication stress, the protein kinase ATR is activated and subsequently transduces genotoxic signals to cell cycle control and DNA repair machinery through phosphorylation of a number of downstream substrates. Very little is known about the molecular mechanism by which ATR is activated in response to genotoxic insults. In this report, we demonstrate that protein phosphatase 5 (PP5) is required for the ATR-mediated checkpoint activation. PP5 forms a complex with ATR in a genotoxic stress-inducible manner. Interference with the expression or the activity of PP5 leads to impairment of the ATR-mediated phosphorylation of hRad17 and Chk1 after UV or hydroxyurea treatment. Similar results are obtained in ATM-deficient cells, suggesting that the observed defect in checkpoint signaling is the consequence of impaired functional interaction between ATR and PP5. In cells exposed to UV irradiation, PP5 is required to elicit an appropriate S-phase checkpoint response. In addition, loss of PP5 leads to premature mitosis after hydroxyurea treatment. Interestingly, reduced PP5 activity exerts differential effects on the formation of intranuclear foci by ATR and replication protein A, implicating a functional role for PP5 in a specific stage of the checkpoint signaling pathway. Taken together, our results suggest that PP5 plays a critical role in the ATR-mediated checkpoint activation.
* Corresponding author. Mailing address: Department of Pharmacology and Cancer Biology, Duke University Medical Center, P.O. Box 3813, Durham, NC 27710. Phone: (919) 681-4861. Fax: (919) 681-7152. E-mail:
wang0011{at}mc.duke.edu.
Molecular and Cellular Biology, November 2005, p. 9910-9919, Vol. 25, No. 22
0022-538X/05/$08.00+0 doi:10.1128/MCB.25.22.9910-9919.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Feng, J., Wakeman, T., Yong, S., Wu, X., Kornbluth, S., Wang, X.-F.
(2009). Protein Phosphatase 2A-Dependent Dephosphorylation of Replication Protein A Is Required for the Repair of DNA Breaks Induced by Replication Stress. Mol. Cell. Biol.
29: 5696-5709
[Abstract]
[Full Text]
-
McConnell, J. L., Wadzinski, B. E.
(2009). Targeting Protein Serine/Threonine Phosphatases for Drug Development. Mol. Pharmacol.
75: 1249-1261
[Abstract]
[Full Text]
-
Kang, Y., Lee, J.-H., Hoan, N. N., Sohn, H.-M., Chang, I.-Y., You, H. J.
(2009). Protein Phosphatase 5 Regulates the Function of 53BP1 after Neocarzinostatin-induced DNA Damage. J. Biol. Chem.
284: 9845-9853
[Abstract]
[Full Text]
-
Tang, X., Hui, Z.-g., Cui, X.-l., Garg, R., Kastan, M. B., Xu, B.
(2008). A Novel ATM-Dependent Pathway Regulates Protein Phosphatase 1 in Response to DNA Damage. Mol. Cell. Biol.
28: 2559-2566
[Abstract]
[Full Text]
-
Yong, W., Bao, S., Chen, H., Li, D., Sanchez, E. R., Shou, W.
(2007). Mice Lacking Protein Phosphatase 5 Are Defective in Ataxia Telangiectasia Mutated (ATM)-mediated Cell Cycle Arrest. J. Biol. Chem.
282: 14690-14694
[Abstract]
[Full Text]
-
Stauffer, D., Chang, B., Huang, J., Dunn, A., Thayer, M.
(2007). p300/CREB-binding Protein Interacts with ATR and Is Required for the DNA Replication Checkpoint. J. Biol. Chem.
282: 9678-9687
[Abstract]
[Full Text]
-
Li, G., Elder, R. T., Qin, K., Park, H. U., Liang, D., Zhao, R. Y.
(2007). Phosphatase Type 2A-dependent and -independent Pathways for ATR Phosphorylation of Chk1. J. Biol. Chem.
282: 7287-7298
[Abstract]
[Full Text]
-
Fu, Z., Larson, K. A., Chitta, R. K., Parker, S. A., Turk, B. E., Lawrence, M. W., Kaldis, P., Galaktionov, K., Cohn, S. M., Shabanowitz, J., Hunt, D. F., Sturgill, T. W.
(2006). Identification of Yin-Yang Regulators and a Phosphorylation Consensus for Male Germ Cell-Associated Kinase (MAK)-Related Kinase. Mol. Cell. Biol.
26: 8639-8654
[Abstract]
[Full Text]
-
Leung-Pineda, V., Ryan, C. E., Piwnica-Worms, H.
(2006). Phosphorylation of Chk1 by ATR Is Antagonized by a Chk1-Regulated Protein Phosphatase 2A Circuit. Mol. Cell. Biol.
26: 7529-7538
[Abstract]
[Full Text]
-
Partch, C. L., Shields, K. F., Thompson, C. L., Selby, C. P., Sancar, A.
(2006). Posttranslational regulation of the mammalian circadian clock by cryptochrome and protein phosphatase 5. Proc. Natl. Acad. Sci. USA
103: 10467-10472
[Abstract]
[Full Text]