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:

Feedback repression is required for mammalian circadian clock function

Abstract

Direct evidence for the requirement of transcriptional feedback repression in circadian clock function has been elusive. Here, we developed a molecular genetic screen in mammalian cells to identify mutants of the circadian transcriptional activators CLOCK and BMAL1, which were uncoupled from CRYPTOCHROME (CRY)-mediated transcriptional repression. Notably, mutations in the PER-ARNT-SIM domain of CLOCK and the C terminus of BMAL1 resulted in synergistic insensitivity through reduced physical interactions with CRY. Coexpression of these mutant proteins in cultured fibroblasts caused arrhythmic phenotypes in population and single-cell assays. These data demonstrate that CRY-mediated repression of the CLOCK/BMAL1 complex activity is required for maintenance of circadian rhythmicity and provide formal proof that transcriptional feedback is required for mammalian clock 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: Mutations in CLOCK and BMAL1 confer insensitivity to CRY-mediated transcriptional repression without affecting CLOCK/BMAL1 transcriptional activity.
Figure 2: Coexpression of CLOCK and BMAL1 desensitized mutants confers synergistic insensitivity to CRY1 in HEK293T cells.
Figure 3: Mutations in the CLOCK PAS domain and BMAL1 C terminus abrogate interactions between the CLOCK/BMAL1 complex and transcriptional repressors CRY1 and PER2.
Figure 4: Coexpression of CLOCK/BMAL1 mutant heterodimers that are insensitive to CRY repression ablates circadian E-box and RORE activities in NIH3T3 cells.
Figure 5: Coexpression of CLOCK/BMAL1 mutant heterodimers impairs circadian rhythmicity in individual cells.

Similar content being viewed by others

References

  1. Dunlap, J.C. Molecular bases for circadian clocks. Cell 96, 271–290 (1999).

    Article  CAS  Google Scholar 

  2. Young, M.W. & Kay, S.A. Time zones: a comparative genetics of circadian clocks. Nat. Rev. Genet. 2, 702–715 (2001).

    Article  CAS  Google Scholar 

  3. Reppert, S.M. & Weaver, D.R. Coordination of circadian timing in mammals. Nature 418, 935–941 (2002).

    Article  CAS  Google Scholar 

  4. Nakajima, M. et al. Reconstitution of circadian oscillation of cyanobacterial KaiC phosphorylation in vitro. Science 308, 414–415 (2005).

    Article  CAS  Google Scholar 

  5. Tomita, J., Nakajima, M., Kondo, T. & Iwasaki, H. No transcription-translation feedback in circadian rhythm of KaiC phosphorylation. Science 307, 251–254 (2005).

    Article  CAS  Google Scholar 

  6. Etchegaray, J.P., Lee, C., Wade, P.A. & Reppert, S.M. Rhythmic histone acetylation underlies transcription in the mammalian circadian clock. Nature 421, 177–182 (2003).

    Article  CAS  Google Scholar 

  7. Gekakis, N. et al. Role of the CLOCK protein in the mammalian circadian mechanism. Science 280, 1564–1569 (1998).

    Article  CAS  Google Scholar 

  8. Yoo, S.H. et al. A noncanonical E-box enhancer drives mouse Period2 circadian oscillations in vivo. Proc. Natl. Acad. Sci. USA 102, 2608–2613 (2005).

    Article  CAS  Google Scholar 

  9. Griffin, E.A. Jr., Staknis, D. & Weitz, C.J. Light-independent role of CRY1 and CRY2 in the mammalian circadian clock. Science 286, 768–771 (1999).

    Article  CAS  Google Scholar 

  10. Sangoram, A.M. et al. Mammalian circadian autoregulatory loop: a timeless ortholog and mPer1 interact and negatively regulate CLOCK-BMAL1-induced transcription. Neuron 21, 1101–1113 (1998).

    Article  CAS  Google Scholar 

  11. Kume, K. et al. mCRY1 and mCRY2 are essential components of the negative limb of the circadian clock feedback loop. Cell 98, 193–205 (1999).

    Article  CAS  Google Scholar 

  12. Shearman, L.P. et al. Interacting molecular loops in the mammalian circadian clock. Science 288, 1013–1019 (2000).

    Article  CAS  Google Scholar 

  13. van der Horst, G.T. et al. Mammalian Cry1 and Cry2 are essential for maintenance of circadian rhythms. Nature 398, 627–630 (1999).

    Article  CAS  Google Scholar 

  14. Vitaterna, M.H. et al. Differential regulation of mammalian period genes and circadian rhythmicity by cryptochromes 1 and 2. Proc. Natl. Acad. Sci. USA 96, 12114–12119 (1999).

    Article  CAS  Google Scholar 

  15. Zheng, B. et al. Nonredundant roles of the mPer1 and mPer2 genes in the mammalian circadian clock. Cell 105, 683–694 (2001).

    Article  CAS  Google Scholar 

  16. Gu, Y.Z., Hogenesch, J.B. & Bradfield, C.A. The PAS superfamily: sensors of environmental and developmental signals. Annu. Rev. Pharmacol. Toxicol. 40, 519–561 (2000).

    Article  CAS  Google Scholar 

  17. Hogenesch, J.B., Gu, Y.Z., Jain, S. & Bradfield, C.A. The basic-helix-loop-helix-PAS orphan MOP3 forms transcriptionally active complexes with circadian and hypoxia factors. Proc. Natl. Acad. Sci. USA 95, 5474–5479 (1998).

    Article  CAS  Google Scholar 

  18. McNamara, P. et al. Regulation of CLOCK and MOP4 by nuclear hormone receptors in the vasculature: a humoral mechanism to reset a peripheral clock. Cell 105, 877–889 (2001).

    Article  CAS  Google Scholar 

  19. Reick, M., Garcia, J.A., Dudley, C. & McKnight, S.L. NPAS2: an analog of clock operative in the mammalian forebrain. Science 293, 506–509 (2001).

    Article  CAS  Google Scholar 

  20. Yildiz, O. et al. Crystal structure and interactions of the PAS repeat region of the Drosophila clock protein PERIOD. Mol. Cell 17, 69–82 (2005).

    Article  CAS  Google Scholar 

  21. Eide, E.J., Vielhaber, E.L., Hinz, W.A. & Virshup, D.M. The circadian regulatory proteins BMAL1 and cryptochromes are substrates of casein kinase Iepsilon. J. Biol. Chem. 277, 17248–17254 (2002).

    Article  CAS  Google Scholar 

  22. Lowrey, P.L. et al. Positional syntenic cloning and functional characterization of the mammalian circadian mutation tau. Science 288, 483–491 (2000).

    Article  CAS  Google Scholar 

  23. Lee, C., Etchegaray, J., Cagampang, F.R., Loudon, A.S. & Reppert, S.M. Posttranslational mechanisms regulate the mammalian circadian clock. Cell 107, 855–867 (2001).

    Article  CAS  Google Scholar 

  24. Okamura, H. et al. Photic induction of mPer1 and mPer2 in cry-deficient mice lacking a biological clock. Science 286, 2531–2534 (1999).

    Article  CAS  Google Scholar 

  25. Ueda, H.R. et al. A transcription factor response element for gene expression during circadian night. Nature 418, 534–539 (2002).

    Article  CAS  Google Scholar 

  26. Ueda, H.R. et al. System-level identification of transcriptional circuits underlying mammalian circadian clocks. Nat. Genet. 37, 187–192 (2005).

    Article  CAS  Google Scholar 

  27. Preitner, N. et al. The orphan nuclear receptor REV-ERBalpha controls circadian transcription within the positive limb of the mammalian circadian oscillator. Cell 110, 251–260 (2002).

    Article  CAS  Google Scholar 

  28. Sato, T.K. et al. A functional genomics strategy reveals Rora as a component of the mammalian circadian clock. Neuron 43, 527–537 (2004).

    Article  CAS  Google Scholar 

  29. Akashi, M. & Takumi, T. The orphan nuclear receptor RORalpha regulates circadian transcription of the mammalian core-clock Bmal1. Nat. Struct. Mol. Biol. 12, 441–448 (2005).

    Article  CAS  Google Scholar 

  30. Welsh, D.K., Yoo, S.-H., Liu, A.C., Takahashi, J.S. & Kay, S.A. Bioluminescence imaging of individual fibroblasts reveals persistent, independently phased circadian rhythms of clock gene expression. Curr. Biol. 14, 2289–2295 (2004).

    Article  CAS  Google Scholar 

  31. Panda, S. et al. Coordinated transcription of key pathways in the mouse by the circadian clock. Cell 109, 307–320 (2002).

    Article  CAS  Google Scholar 

  32. Lowrey, P.L. & Takahashi, J.S. Mammalian circadian biology: elucidating genome-wide levels of temporal organization. Annu. Rev. Genomics Hum. Genet. 5, 407–441 (2004).

    Article  CAS  Google Scholar 

  33. Cook, E. & Peters, K. The smoothing spline: A new approach to standardizing forest interior tree-ring width series for dendroclimatic studies. Tree-Ring Bull. 41, 45–53 (1981).

    Google Scholar 

Download references

Acknowledgements

This research was supported by the Novartis Research Foundation (L.J.M. and J.B.H.), a Rena and Victor Damone Postdoctoral Fellowship from the American Cancer Society (T.K.S.), US National Institute of Health (NIH) grants (D.K.W. and S.A.K.), Scripps Florida (T.K.S., J.E.B., and J.B.H.), RIKEN Center for Developmental Biology (H.R.U.), NIH/Silvio O. Conti Center for Neuroscience grant P50 MH074924-01 (J.E.B. and J.H.), RIKEN Strategic Programs (H.U. and H.R.U.), New Energy and Industrial Technology Organization (NEDO) Scientific Research grant (H.R.U.) and Scientific Research grant and Genome Network Project grant from the Japanese Ministry of Education, Culture, Sports, Science and Technology (H.R.U.). This is manuscript number 17558-CB of The Scripps Research Institute. We thank N. Gekakis, S. Reppert, C. Joazeiro, A. Curtis and G. FitzGerald for plasmids; S. Panda for anti-mCRY1; J. Zhang and T. Orth for robotics support; T. Kondo for high-throughput monitoring systems; M. Ukai-Tadenuma, J. Cartzendafner and J. Geskes for technical support and S. Panda, R. Van Gelder, T. Reyes, M. Pletcher, K. Hayes, B. Miller, M. Conkright and M. Givens for critical reading of the manuscript.

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Hiroki R Ueda or John B Hogenesch.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Fig. 1

Single mutations in CLOCK and BMAL1 desensitize CLOCK/BMAL1 heterodimers to CRY1. (PDF 779 kb)

Supplementary Fig. 2

Double mutant circadian heterodimers are synergistically insensitive to CRY-mediated repression. (PDF 425 kb)

Supplementary Fig. 3

Desensitization to CRY is not due to enhanced stability or expression of mutant CLOCK or BMAL1. (PDF 196 kb)

Supplementary Fig. 4

Overexpression of wild-type CLOCK and BMAL1 differentially affect amplitude of cycling of the PER2 and BMAL1 reporters in real-time bioluminescence assays. (PDF 682 kb)

Supplementary Fig. 5

Double CLOCK/BMAL1 mutant heterodimers are insensitive to CRY-mediated activation of BMAL1 expression. (PDF 167 kb)

Supplementary Fig. 6

Expression of wild-type CLOCK/BMAL1 does not alter circadian PER2 expression in individual NIH3T3 fibroblasts. (PDF 326 kb)

Supplementary Fig. 7

Expression of CLOCK1/BMAL1 double mutants causes arrhythmic PER2 expression in individual NIH3T3 fibroblasts. (PDF 281 kb)

Supplementary Fig. 8

Coexpression of Clock-3/Bmal1–4 mutant heterodimers impairs circadian rhythmicity in individual cells. (PDF 1775 kb)

Supplementary Methods (PDF 28 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Sato, T., Yamada, R., Ukai, H. et al. Feedback repression is required for mammalian circadian clock function. Nat Genet 38, 312–319 (2006). https://doi.org/10.1038/ng1745

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ng1745

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