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.

  • Article
  • Published:

Bmi1 regulates mitochondrial function and the DNA damage response pathway

Abstract

Mice deficient in the Polycomb repressor Bmi1 develop numerous abnormalities including a severe defect in stem cell self-renewal, alterations in thymocyte maturation and a shortened lifespan. Previous work has implicated de-repression of the Ink4a/Arf (also known as Cdkn2a) locus as mediating many of the aspects of the Bmi1-/- phenotype. Here we demonstrate that cells derived from Bmi1-/- mice also have impaired mitochondrial function, a marked increase in the intracellular levels of reactive oxygen species and subsequent engagement of the DNA damage response pathway. Furthermore, many of the deficiencies normally observed in Bmi1-/- mice improve after either pharmacological treatment with the antioxidant N-acetylcysteine or genetic disruption of the DNA damage response pathway by Chk2 (also known as Chek2) deletion. These results demonstrate that Bmi1 has an unexpected role in maintaining mitochondrial function and redox homeostasis and indicate that the Polycomb family of proteins can coordinately regulate cellular metabolism with stem and progenitor cell function.

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: The absence of Bmi1 increases ROS levels and alters mitochondrial function.
Figure 2: Antioxidant treatment rescues Bmi1 -/- thymocytes.
Figure 3: Activation of the DDR pathway in Bmi1 -/- thymocytes occurs through a redox-sensitive pathway.
Figure 4: Inhibition of the DDR pathway by Chk2 deletion rescues multiple defects in Bmi1 -/- mice.

Similar content being viewed by others

References

  1. Park, I. K. et al. Bmi-1 is required for maintenance of adult self-renewing haematopoietic stem cells. Nature 423, 302–305 (2003)

    Article  ADS  CAS  Google Scholar 

  2. Molofsky, A. V. et al. Bmi-1 dependence distinguishes neural stem cell self-renewal from progenitor proliferation. Nature 425, 962–967 (2003)

    Article  ADS  CAS  Google Scholar 

  3. van der Lugt, N. M. et al. Posterior transformation, neurological abnormalities, and severe hematopoietic defects in mice with a targeted deletion of the bmi-1 proto-oncogene. Genes Dev. 8, 757–769 (1994)

    Article  CAS  Google Scholar 

  4. Jacobs, J. J., Kieboom, K., Marino, S., DePinho, R. A. & van Lohuizen, M. The oncogene and Polycomb-group gene bmi-1 regulates cell proliferation and senescence through the ink4a locus. Nature 397, 164–168 (1999)

    Article  ADS  CAS  Google Scholar 

  5. Bruggeman, S. W. et al. Ink4a and Arf differentially affect cell proliferation and neural stem cell self-renewal in Bmi1-deficient mice. Genes Dev. 19, 1438–1443 (2005)

    Article  CAS  Google Scholar 

  6. Molofsky, A. V., He, S., Bydon, M., Morrison, S. J. & Pardal, R. Bmi-1 promotes neural stem cell self-renewal and neural development but not mouse growth and survival by repressing the p16Ink4a and p19Arf senescence pathways. Genes Dev. 19, 1432–1437 (2005)

    Article  CAS  Google Scholar 

  7. Bracken, A. P. et al. The Polycomb group proteins bind throughout the INK4A-ARF locus and are disassociated in senescent cells. Genes Dev. 21, 525–530 (2007)

    Article  CAS  Google Scholar 

  8. Oguro, H. et al. Differential impact of Ink4a and Arf on hematopoietic stem cells and their bone marrow microenvironment in Bmi1-deficient mice. J. Exp. Med. 203, 2247–2253 (2006)

    Article  CAS  Google Scholar 

  9. Tothova, Z. et al. FoxOs are critical mediators of hematopoietic stem cell resistance to physiologic oxidative stress. Cell 128, 325–339 (2007)

    Article  CAS  Google Scholar 

  10. Ito, K. et al. Regulation of oxidative stress by ATM is required for self-renewal of haematopoietic stem cells. Nature 431, 997–1002 (2004)

    Article  ADS  CAS  Google Scholar 

  11. Kiel, M. J. et al. SLAM family receptors distinguish hematopoietic stem and progenitor cells and reveal endothelial niches for stem cells. Cell 121, 1109–1121 (2005)

    Article  CAS  Google Scholar 

  12. Bracken, A. P., Dietrich, N., Pasini, D., Hansen, K. H. & Helin, K. Genome-wide mapping of Polycomb target genes unravels their roles in cell fate transitions. Genes Dev. 20, 1123–1136 (2006)

    Article  CAS  Google Scholar 

  13. Fasano, C. A. et al. shRNA knockdown of Bmi-1 reveals a critical role for p21-Rb pathway in NSC self-renewal during development. Cell Stem Cell 1, 87–99 (2007)

    Article  CAS  Google Scholar 

  14. Balaban, R. S., Nemoto, S. & Finkel, T. Mitochondria, oxidants, and aging. Cell 120, 483–495 (2005)

    Article  CAS  Google Scholar 

  15. Takahashi, A. et al. Mitogenic signalling and the p16INK4a-Rb pathway cooperate to enforce irreversible cellular senescence. Nature Cell Biol. 8, 1291–1297 (2006)

    Article  CAS  Google Scholar 

  16. Lombard, D. B. et al. DNA repair, genome stability, and aging. Cell 120, 497–512 (2005)

    Article  CAS  Google Scholar 

  17. Adams, M. M. & Carpenter, P. B. Tying the loose ends together in DNA double strand break repair with 53BP1. Cell Div 1, 19 (2006)

    Article  Google Scholar 

  18. Takai, H. et al. Chk2-deficient mice exhibit radioresistance and defective p53-mediated transcription. EMBO J. 21, 5195–5205 (2002)

    Article  CAS  Google Scholar 

  19. Hirao, A. et al. Chk2 is a tumor suppressor that regulates apoptosis in both an ataxia telangiectasia mutated (ATM)-dependent and an ATM-independent manner. Mol. Cell. Biol. 22, 6521–6532 (2002)

    Article  CAS  Google Scholar 

  20. Okada, H. et al. Survivin loss in thymocytes triggers p53-mediated growth arrest and p53-independent cell death. J. Exp. Med. 199, 399–410 (2004)

    Article  CAS  Google Scholar 

  21. Zaugg, K. et al. Cross-talk between Chk1 and Chk2 in double-mutant thymocytes. Proc. Natl Acad. Sci. USA 104, 3805–3810 (2007)

    Article  ADS  CAS  Google Scholar 

  22. Rossi, D. J. et al. Deficiencies in DNA damage repair limit the function of haematopoietic stem cells with age. Nature 447, 725–729 (2007)

    Article  ADS  CAS  Google Scholar 

  23. Reese, J. S., Liu, L. & Gerson, S. L. Repopulating defect of mismatch repair-deficient hematopoietic stem cells. Blood 102, 1626–1633 (2003)

    Article  CAS  Google Scholar 

  24. Nijnik, A. et al. DNA repair is limiting for haematopoietic stem cells during ageing. Nature 447, 686–690 (2007)

    Article  ADS  CAS  Google Scholar 

  25. Viale, A. et al. Cell-cycle restriction limits DNA damage and maintains self-renewal of leukaemia stem cells. Nature 457, 51–56 (2009)

    Article  ADS  CAS  Google Scholar 

  26. Rossi, D. J., Jamieson, C. H. & Weissman, I. L. Stems cells and the pathways to aging and cancer. Cell 132, 681–696 (2008)

    Article  CAS  Google Scholar 

  27. Janzen, V. et al. Stem-cell ageing modified by the cyclin-dependent kinase inhibitor p16INK4a. Nature 443, 421–426 (2006)

    Article  ADS  CAS  Google Scholar 

  28. Molofsky, A. V. et al. Increasing p16INK4a expression decreases forebrain progenitors and neurogenesis during ageing. Nature 443, 448–452 (2006)

    Article  ADS  CAS  Google Scholar 

  29. Krishnamurthy, J. et al. p16INK4a induces an age-dependent decline in islet regenerative potential. Nature 443, 453–457 (2006)

    Article  ADS  CAS  Google Scholar 

  30. Collado, M., Blasco, M. A. & Serrano, M. Cellular senescence in cancer and aging. Cell 130, 223–233 (2007)

    Article  CAS  Google Scholar 

  31. Finkel, T., Serrano, M. & Blasco, M. A. The common biology of cancer and ageing. Nature 448, 767–774 (2007)

    Article  ADS  CAS  Google Scholar 

  32. Ferrick, D. A., Neilson, A. & Beeson, C. Advances in measuring cellular bioenergetics using extracellular flux. Drug Discov. Today 13, 268–274 (2008)

    Article  CAS  Google Scholar 

  33. Struthers, L., Patel, R., Clark, J. & Thomas, S. Direct detection of 8-oxodeoxyguanosine and 8-oxoguanine by avidin and its analogues. Anal. Biochem. 255, 20–31 (1998)

    Article  CAS  Google Scholar 

  34. Neumann, C. A. et al. Essential role for the peroxiredoxin Prdx1 in erythrocyte antioxidant defence and tumour suppression. Nature 424, 561–565 (2003)

    Article  ADS  CAS  Google Scholar 

  35. Sharpless, N. E. et al. Loss of p16Ink4a with retention of p19Arf predisposes mice to tumorigenesis. Nature 413, 86–91 (2001)

    Article  ADS  CAS  Google Scholar 

  36. Smith, A. L., Ellison, F. M., McCoy, J. P. & Chen, J. c-Kit expression and stem cell factor-induced hematopoietic cell proliferation are up-regulated in aged B6D2F1 mice. J. Gerontol. A Biol. Sci. Med. Sci. 60, 448–456 (2005)

    Article  Google Scholar 

  37. Schieke, S. M. et al. The mammalian target of rapamycin (mTOR) pathway regulates mitochondrial oxygen consumption and oxidative capacity. J. Biol. Chem. 281, 27643–27652 (2006)

    Article  CAS  Google Scholar 

  38. TeKippe, M., Harrison, D. E. & Chen, J. Expansion of hematopoietic stem cell phenotype and activity in Trp53-null mice. Exp. Hematol. 31, 521–527 (2003)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We are grateful to M. Clarke for providing the initial supply of Bmi1-/- mice, to J. Moss for the gift of anti-PARP antibodies and to M. Daniels and the NHLBI electron microscope core for their assistance. This work was supported by funding from the NIH intramural program and the Ellison Medical Foundation.

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Liu Cao or Toren Finkel.

Supplementary information

Supplementary Information

This file contains Supplementary Figures 1-13 with Legends, Supplementary Methods and Materials and Supplementary References. (PDF 1043 kb)

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Cite this article

Liu, J., Cao, L., Chen, J. et al. Bmi1 regulates mitochondrial function and the DNA damage response pathway. Nature 459, 387–392 (2009). https://doi.org/10.1038/nature08040

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature08040

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