Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

MDC1 is a mediator of the mammalian DNA damage checkpoint

Abstract

To counteract the continuous exposure of cells to agents that damage DNA, cells have evolved complex regulatory networks called checkpoints to sense DNA damage and coordinate DNA replication, cell-cycle arrest and DNA repair1. It has recently been shown that the histone H2A variant H2AX specifically controls the recruitment of DNA repair proteins to the sites of DNA damage2,3,4. Here we identify a novel BRCA1 carboxy-terminal (BRCT) and forkhead-associated (FHA) domain-containing protein, MDC1 (mediator of DNA damage checkpoint protein 1), which works with H2AX to promote recruitment of repair proteins to the sites of DNA breaks and which, in addition, controls damage-induced cell-cycle arrest checkpoints. MDC1 forms foci that co-localize extensively with γ-H2AX foci within minutes after exposure to ionizing radiation. H2AX is required for MDC1 foci formation, and MDC1 forms complexes with phosphorylated H2AX. Furthermore, this interaction is phosphorylation dependent as peptides containing the phosphorylated site on H2AX bind MDC1 in a phosphorylation-dependent manner. We have shown by using small interfering RNA (siRNA) that cells lacking MDC1 are sensitive to ionizing radiation, and that MDC1 controls the formation of damage-induced 53BP1, BRCA1 and MRN foci, in part by promoting efficient H2AX phosphorylation. In addition, cells lacking MDC1 also fail to activate the intra-S phase and G2/M phase cell-cycle checkpoints properly after exposure to ionizing radiation, which was associated with an inability to regulate Chk1 properly. These results highlight a crucial role for MDC1 in mediating transduction of the DNA damage signal.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: MDC1 is phosphorylated in response to DNA damage and DNA replication stress.
Figure 5: MDC1 inhibition results in defective IR-induced checkpoints and Chk1 and H2AX phosphorylation.
Figure 2: MDC1 regulates BRCA1, 53BP1 and Nbs1 foci formation.
Figure 3: MDC1 associates with DNA damage checkpoint proteins.
Figure 4: Interactions between MDC1 and H2AX.

Similar content being viewed by others

References

  1. Zhou, B. B. & Elledge, S. J. The DNA damage response: putting checkpoints in perspective. Nature 408, 433–439 (2000)

    Article  ADS  CAS  PubMed  Google Scholar 

  2. Bassing, C. H. et al. Increased ionizing radiation sensitivity and genomic instability in the absence of histone H2AX. Proc. Natl Acad. Sci. USA 99, 8173–8178 (2002)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  3. Celeste, A. et al. Genomic instability in mice lacking histone H2AX. Science 296, 922–927 (2002)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  4. Fernandez-Capetillo, O. et al. DNA damage-induced G(2)-M checkpoint activation by histone H2AX and 53BP1. Nature Cell Biol. 4, 993–997 (2002)

    Article  CAS  PubMed  Google Scholar 

  5. Vialard, J. E., Gilbert, C. S., Green, C. M. & Lowndes, N. F. The budding yeast Rad9 checkpoint protein is subjected to Mec1/Tel1-dependent hyperphosphorylation and interacts with Rad53 after DNA damage. EMBO J. 17, 5679–5688 (1998)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  6. Gilbert, C. S., Green, C. M. & Lowndes, N. F. Budding yeast Rad9 is an ATP-dependent Rad53 activating machine. Mol. Cell. 8, 129–136 (2001)

    Article  CAS  PubMed  Google Scholar 

  7. Soulier, J. & Lowndes, N. F. The BRCT domain of the S. cerevisiae checkpoint protein Rad9 mediates a Rad9-Rad9 interaction after DNA damage. Curr. Biol. 9, 551–554 (1999)

    Article  CAS  PubMed  Google Scholar 

  8. Schultz, L. B., Chehab, N. H., Malikzay, A. & Halazonetis, T. D. p53 binding protein 1 (53BP1) is an early participant in the cellular response to DNA double-strand breaks. J. Cell Biol. 151, 1381–1390 (2000)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Venkitaraman, A. R. Functions of BRCA1 and BRCA2 in the biological response to DNA damage. J. Cell Sci. 114, 3591–3598 (2001)

    CAS  PubMed  Google Scholar 

  10. Wang, B., Matsuoka, S., Carpenter, P. & Elledge, S. J. 53BP1, a mediator of the DNA damage checkpoint. Science 298, 1435–1438 (2002)

    Article  ADS  CAS  PubMed  Google Scholar 

  11. Yamane, K., Wu, X. & Chen, J. A DNA damage-regulated BRCT-containing protein, TopBP1, is required for cell survival. Mol. Cell. Biol. 22, 555–566 (2002)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Callebaut, I. & Mornon, J. P. From BRCA1 to RAP1: a widespread BRCT module closely associated with DNA repair. FEBS Lett. 400, 25–30 (1997)

    Article  CAS  PubMed  Google Scholar 

  13. Ozaki, T. et al. NFBD1/KIAA0170 is a novel nuclear transcriptional transactivator with BRCT domain. DNA Cell Biol. 19, 475–485 (2000)

    Article  CAS  PubMed  Google Scholar 

  14. Huang, M. & Elledge, S. J. in Cold Spring Harbor Symposia on Quantitative Biology Vol. LXV, 1–9 (Cold Spring Harbor Laboratory Press, New York, 2000)

    Google Scholar 

  15. Durocher, D. & Jackson, S. P. The FHA domain. FEBS Lett. 513, 58–66 (2002)

    Article  CAS  PubMed  Google Scholar 

  16. 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  ADS  CAS  PubMed  Google Scholar 

  17. 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  PubMed  Google Scholar 

  18. Matsuoka, S. et al. Ataxia telangiectasia-mutated phosphorylates Chk2 in vivo and in vitro. Proc. Natl Acad. Sci. USA 97, 10389–10394 (2000)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  19. 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  PubMed  PubMed Central  Google Scholar 

  20. Paull, T. T. et al. A critical role for histone H2AX in recruitment of repair factors to nuclear foci after DNA damage. Curr. Biol. 10, 886–895 (2000)

    Article  CAS  PubMed  Google Scholar 

  21. Wang, Y. et al. BASC, a super complex of BRCA1-associated proteins involved in the recognition and repair of aberrant DNA structures. Genes Dev. 14, 927–939 (2000)

    CAS  PubMed  PubMed Central  Google Scholar 

  22. Rogakou, E. P., Boon, C., Redon, C. & Bonner, W. M. Megabase chromatin domains involved in DNA double-strand breaks in vivo. J. Cell Biol. 146, 905–916 (1999)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Rappold, I., Iwabuchi, K., Date, T. & Chen, J. Tumor suppressor p53 binding protein 1 (53BP1) is involved in DNA damage-signaling pathways. J. Cell Biol. 153, 613–620 (2001)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Takai, H. et al. Aberrant cell cycle checkpoint function and early embryonic death in Chk1-/- mice. Genes Dev. 14, 1439–1447 (2000)

    CAS  PubMed  PubMed Central  Google Scholar 

  25. Liu, Q. et al. Chk1 is an essential kinase that is regulated by Atr and required for the G2/M DNA damage checkpoint. Genes Dev. 14, 1448–1459 (2001)

    Google Scholar 

  26. Kim, S. T., Xu, B. & Kastan, M. B. Involvement of the cohesin protein, Smc1, in Atm-dependent and independent responses to DNA damage. Genes Dev. 16, 560–570 (2002)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Yazdi, P. T. et al. SMC1 is a downstream effector in the ATM/NBS1 branch of the human S-phase checkpoint. Genes Dev. 16, 571–582 (2002)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Zhao, H., Watkins, J. L. & Piwnica-Worms, H. Disruption of the checkpoint kinase 1/cell division cycle 25A pathway abrogates ionizing radiation-induced S and G2 checkpoints. Proc. Natl Acad. Sci. USA 99, 14795–14800 (2002)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

We thank A. Nussenzweig for the gift of the H2AX null MEFS and the corresponding wild-type MEFs. We thank P. Cooper, J. Chen and S. Jackson for sharing unpublished information and helpful discussions. We thank D. Lou for excellent technical assistance and N. Foray for technical advice. This work was supported by a National Institutes of Health Grant to S.J.E. B.W. is a fellow of the US Army Breast Cancer Postdoctoral Trainee Award, and S.J.E. is supported by a grant from the NIH, is an Investigator with the Howard Hughes Medical Institute and is a Senior Scholar of the Ellison Foundation. C.R.B. is supported by the Leukemia Research Fund. G.S.S. is supported by the European Molecular Biology Organization (EMBO).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Stephen J. Elledge.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Cite this article

Stewart, G., Wang, B., Bignell, C. et al. MDC1 is a mediator of the mammalian DNA damage checkpoint. Nature 421, 961–966 (2003). https://doi.org/10.1038/nature01446

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature01446

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing