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BRCA1 regulates the G2/M checkpoint by activating Chk1 kinase upon DNA damage

Abstract

The breast cancer tumor-suppressor gene, BRCA1, encodes a protein with a BRCT domain—a motif that is found in many proteins that are implicated in DNA damage response and in genome stability1. Phosphorylation of BRCA1 by the DNA damage-response proteins ATM, ATR and hCds1/Chk2 changes in response to DNA damage and at replication-block checkpoints2,3,4,5. Although cells that lack BRCA1 have an abnormal response to DNA damage, the exact role of BRCA1 in this process has remained unclear. Here we show that BRCA1 is essential for activating the Chk1 kinase that regulates DNA damage–induced G2/M arrest. Thus, BRCA1 controls the expression, phosphorylation and cellular localization of Cdc25C and Cdc2/cyclin B kinase—proteins that are crucial for the G2/M transition. We show that BRCA1 regulates the expression of both Wee1 kinase, an inhibitor of Cdc2/cyclin B kinase, and the 14-3-3 family of proteins that sequesters phosphorylated Cdc25C and Cdc2/cyclin B kinase in the cytoplasm6. We conclude that BRCA1 regulates key effectors that control the G2/M checkpoint and is therefore involved in regulating the onset of mitosis.

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Figure 1: Expression of BRCA1 restores the G2/M checkpoint and regulates the expression and activity of checkpoint proteins.
Figure 2: BRCA1 alters the expression and localization of G2/M checkpoint proteins.
Figure 3: BRCA1 activates Chk1 kinase activity.
Figure 4: BRCA1 and Chk1 associate in vivo.
Figure 5: A model of the DNA damage checkpoint that integrates BRCA1.

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References

  1. Bork, P. et al. A superfamily of conserved domains in DNA damage-responsive cell cycle checkpoint proteins. FASEB J. 11, 68–76 (1997).

    Article  CAS  Google Scholar 

  2. Cortez, D., Wang, Y., Qin, J. & Elledge, S.J. Requirement of ATM-dependent phosphorylation of brca1 in the DNA damage response to double-strand breaks. Science 286, 1162–1166 (1999).

    Article  CAS  Google Scholar 

  3. Tibbetts, R.S. et al. Functional interactions between BRCA1 and the checkpoint kinase ATR during genotoxic stress. Genes Dev. 14, 2989–3002 (2000).

    Article  CAS  Google Scholar 

  4. Lee, J.S., Collins, K.M., Brown, A.L., Lee, C.H. & Chung, J.H. hCds1-mediated phosphorylation of BRCA1 regulates the DNA damage response. Nature 404, 201–204 (2000).

    Article  CAS  Google Scholar 

  5. Chen, J. Ataxia telangiectasia-related protein is involved in the phosphorylation of BRCA1 following deoxyribonucleic acid damage. Cancer Res. 60, 5037–5039 (2000).

    CAS  PubMed  Google Scholar 

  6. Lopez-Girona, A., Furnari, B., Mondesert, O. & Russell, P. Nuclear localization of Cdc25 is regulated by DNA damage and a 14-3-3 protein. Nature 397, 172–175 (1999).

    Article  CAS  Google Scholar 

  7. Tomlinson, G.E. et al. Characterization of a breast cancer cell line derived from a germ-line BRCA1 mutation carrier. Cancer Res. 58, 3237–3242 (1998).

    CAS  PubMed  Google Scholar 

  8. Scully, R. et al. Genetic analysis of BRCA1 function in a defined tumor cell line. Mol. Cell 4, 1093–1099 (1999).

    Article  CAS  Google Scholar 

  9. Foray, N. et al. Γ-rays-induced death of human cells carrying mutations of BRCA1 or BRCA2. Oncogene 18, 7334–7342 (1999).

    Article  CAS  Google Scholar 

  10. Xu, B., Kim, S. & Kastan, M.B. Involvement of BRCA1 in S-phase and G2-phase checkpoints after ionizing irradiation. Mol. Cell. Biol. 21, 3445–3450 (2001).

    Article  CAS  Google Scholar 

  11. Zhong, Q. et al. Association of BRCA1 with the hRad50-hMre11-p95 complex and the DNA damage response. Science 285, 747–750 (1999).

    Article  CAS  Google Scholar 

  12. MacLachlan, T.K. et al. BRCA1 effects on the cell cycle and the DNA damage response are linked to altered gene expression. J. Biol. Chem. 275, 2777–2785 (2000).

    Article  CAS  Google Scholar 

  13. O'Connor, P.M. et al. G2 delay induced by nitrogen mustard in human cells affects cyclin A/Cdk2 and cyclin B1/Cdc2-kinase complexes differently. J. Biol. Chem. 268, 8298–8308 (1993).

    CAS  PubMed  Google Scholar 

  14. Rhind, N., Furnari, B. & Russell, P. Cdc2 tyrosine phosphorylation is required for the DNA damage checkpoint in fission yeast. Genes Dev. 11, 504–511 (1997).

    Article  CAS  Google Scholar 

  15. Lee, M.S. et al. Cdc25+ encodes a protein phosphatase that dephosphorylates p34cdc2. Mol. Biol. Cell 3, 73–84 (1992).

    Article  CAS  Google Scholar 

  16. Ogg, S., Gabrielli, B. & Piwnica-Worms, H. Purification of a serine kinase that associates with and phosphorylates human Cdc25C on serine 216. J. Biol. Chem. 269, 30461–30469 (1994).

    CAS  PubMed  Google Scholar 

  17. Furnari, B., Rhind, N. & Russell, P. Cdc25 mitotic inducer targeted by Chk1 DNA damage checkpoint kinase. Science 277, 1495–1497 (1997).

    Article  CAS  Google Scholar 

  18. Sanchez, Y. et al. Conservation of the Chk1 checkpoint pathway in mammals: linkage of DNA damage to Cdk regulation through Cdc25. Science 277, 1497–1501 (1997).

    Article  CAS  Google Scholar 

  19. Peng, C.Y. et al. Mitotic and G2 checkpoint control: regulation of 14-3-3 protein binding by phosphorylation of Cdc25C on serine-216. Science 277, 1501–1505 (1997).

    Article  CAS  Google Scholar 

  20. Hermeking, H. et al. 14-3-3σ is a p53-regulated inhibitor of G2/M progression. Mol. Cell 1, 3–11 (1997).

    Article  CAS  Google Scholar 

  21. Matsuoka, S., Huang, M. & Elledge, S.J. Linkage of ATM to cell cycle regulation by the Chk2 protein kinase. Science 282, 1893–1897 (1998).

    Article  CAS  Google Scholar 

  22. Xu, X. et al. Centrosome amplification and a defective G2-M cell cycle checkpoint induce genetic instability in BRCA1 exon 11 isoform-deficient cells. Mol. Cell 3, 389–395 (1999).

    Article  CAS  Google Scholar 

  23. Xu, X. et al. Genetic interactions between tumor suppressors BRCA1 and TP53 in apoptosis, cell cycle and tumorigenesis. Nature Genet. 28, 266–271 (2001).

    Article  CAS  Google Scholar 

  24. van den Heuvel, S. & Harlow, E. Distinct roles for cyclin-dependent kinases in cell cycle control. Science 262, 2050–2054 (1993).

    Article  CAS  Google Scholar 

  25. Yarden, R.I. & Brody, L.C. BRCA1 interacts with components of the histone deacetylase complex. Proc. Natl Acad. Sci. USA 96, 4983–4988 (1999).

    Article  CAS  Google Scholar 

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Acknowledgements

We thank Y. Pommier for the GST–Cdc25C plasmid, C. Smythe for the Chk2 antibody, Y. Shiloh for AT cells, S. Anderson and M. Kirby for flow cytometry, A. Dutra for help with confocal microscopy, E. Sausville and the Drug Synthesis and Chemistry Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis at the National Cancer Institute for providing UCN-01; and P. Liu and S. Danoff for comments on the manuscript.

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Correspondence to Lawrence C. Brody.

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Yarden, R., Pardo-Reoyo, S., Sgagias, M. et al. BRCA1 regulates the G2/M checkpoint by activating Chk1 kinase upon DNA damage. Nat Genet 30, 285–289 (2002). https://doi.org/10.1038/ng837

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