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Cell cycle-dependent regulation of yeast telomerase by Ku

Abstract

The heterodimeric Ku complex affects telomere structure in diverse organisms. We report here that in the absence of Ku, the catalytic subunit of telomerase, Est2p, was not telomere-associated in G1 phase, and its association in late S phase was decreased. The telomere association of Est1p, a telomerase component that binds telomeres only in late S phase, was also reduced in the absence of Ku. The effects of Ku on telomerase binding require a 48-nucleotide (nt) stem-loop region of TLC1 telomerase RNA. Ku interacts with TLC1 RNA via this 48-nt region throughout the cell cycle, but this interaction was reduced after telomere replication. These data support a model in which Ku recruits telomerase to telomeres in G1 phase when telomerase is inactive and promotes telomerase-mediated telomere lengthening in late S phase.

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Figure 1: Ku-TLC1 interaction is required for normal telomere association of Est2p, Est1p and Cdc13p.
Figure 2: Ku-TLC1 interaction is required for normal telomere association of Est2p, Est1p and Cdc13p at telomere VI-R.
Figure 3: Ku-TLC1 interaction is required for the association of Est2p with telomeres in G1 and contributes to its association in late S phase.
Figure 4: Ku-TLC1 interaction is partly responsible for Est1p telomere association in late S phase.
Figure 5: The telomere association of Cdc13p is increased in the absence of Ku but is unaffected by the loss of the Ku-TLC1 interaction.
Figure 6: yKu80p is telomere-associated throughout the cell cycle.
Figure 7: Ku is specifically associated with TLC1 RNA in vivo.

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References

  1. van Steensel, B., Smogorzewska, A. & de lange, T. TRF2 protects human telomeres from end-to-end fusions. Cell 92, 401–413 (1998).

    Article  CAS  PubMed  Google Scholar 

  2. Sandell, L.L. & Zakian, V.A. Loss of a yeast telomere: arrest, recovery and chromosome loss. Cell 75, 729–739 (1993).

    Article  CAS  PubMed  Google Scholar 

  3. Gottschling, D.E., Aparicio, O.M., Billington, B.L. & Zakian, V.A. Position effect at S. cerevisiae telomeres: reversible repression of Pol II transcription. Cell 63, 751–762 (1990).

    Article  CAS  PubMed  Google Scholar 

  4. Baur, J.A., Zou, Y., Shay, J.W. & Wright, W.E. Telomere position effect in human cells. Science 292, 2075–2077 (2001).

    Article  CAS  PubMed  Google Scholar 

  5. Wellinger, R.J., Wolf, A.J. & Zakian, V.A. Origin activation and formation of single-strand TG1–3 tails occur sequentially in late S phase on a yeast linear plasmid. Mol. Cell. Biol. 13, 4057–4065 (1993).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  6. Wellinger, R.J., Wolf, A.J. & Zakian, V.A. Saccharomyces telomeres acquire single-strand TG1–3 tails late in S phase. Cell 72, 51–60 (1993).

    Article  CAS  PubMed  Google Scholar 

  7. Taggart, A.K.P., Teng, S.-C. & Zakian, V.A. Est1p as a cell cycle-regulated activator of telomere-bound telomerase. Science 297, 1023–1026 (2002).

    Article  CAS  PubMed  Google Scholar 

  8. Marcand, S., Brevet, V., Mann, C. & Gilson, E. Cell cycle restriction of telomere elongation. Curr. Biol. 10, 487–490 (2000).

    Article  CAS  PubMed  Google Scholar 

  9. Gravel, S., Larrivee, M., Labrecque, P. & Wellinger, R.J. Yeast Ku as a regulator of chromosomal DNA end structure. Science 280, 741–744 (1998).

    Article  CAS  PubMed  Google Scholar 

  10. Boulton, S.J. & Jackson, S.P. Identification of a Saccharomyces cerevisiae Ku80 homologue: roles in DNA double strand break rejoining and in telomeric maintenance. Nucleic Acids Res. 24, 4639–4648 (1996).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Porter, S.E., Greenwell, P.W., Ritchie, K.B. & Petes, T.D. The DNA-binding protein Hdf1p (a putative Ku homologue) is required for maintaining normal telomere length in Saccharomyces cerevisiae . Nucleic Acids Res. 24, 582–585 (1996).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Polotnianka, R.M., Li, J. & Lustig, A.J. The yeast Ku heterodimer is essential for protection of the telomere against nucleolytic and recombinational activities. Curr. Biol. 8, 831–834 (1998).

    Article  CAS  PubMed  Google Scholar 

  13. Laroche, T. et al. Mutation of yeast Ku genes disrupts the subnuclear organization of telomeres. Curr. Biol. 8, 653–656 (1998).

    Article  CAS  PubMed  Google Scholar 

  14. Hediger, F., Neumann, F.R., Van Houwe, G., Dubrana, K. & Gasser, S.M. Live imaging of telomeres: yKu and Sir proteins define redundant telomere-anchoring pathways in yeast. Curr. Biol. 12, 2076–2089 (2002).

    Article  CAS  PubMed  Google Scholar 

  15. Boulton, S.J. & Jackson, S.P. Components of the Ku-dependent non-homologous end-joining pathway are involved in telomeric length maintenance and telomeric silencing. EMBO J. 17, 1819–1828 (1998).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Nugent, C.I. et al. Telomere maintenance is dependent on activities required for end repair of double-strand breaks. Curr. Biol. 8, 657–660 (1998).

    Article  CAS  PubMed  Google Scholar 

  17. Maringele, L. & Lydall, D. EXO1-dependent single-stranded DNA at telomeres activates subsets of DNA damage and spindle checkpoint pathways in budding yeast yku70Delta mutants. Genes Dev. 16, 1919–1933 (2002).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. DuBois, M.L., Haimberger, Z.W., McIntosh, M.W. & Gottschling, D.E. A quantitative assay for telomere protection in Saccharomyces cerevisiae . Genetics 161, 995–1013 (2002).

    CAS  PubMed  PubMed Central  Google Scholar 

  19. Cosgrove, A.J., Nieduszynski, C.A. & Donaldson, A.D. Ku complex controls the replication time of DNA in telomere regions. Genes Dev. 16, 2485–2490 (2002).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. McAinsh, A.D., Scott-Drew, S., Murray, J.A. & Jackson, S.P. DNA damage triggers disruption of telomeric silencing and Mec1p- dependent relocation of Sir3p. Curr. Biol. 9, 963–966 (1999).

    Article  CAS  PubMed  Google Scholar 

  21. Martin, S.G., Laroche, T., Suka, N., Grunstein, M. & Gasser, S.M. Relocalization of telomeric Ku and SIR proteins in response to DNA strand breaks in yeast. Cell 97, 621–633 (1999).

    Article  CAS  PubMed  Google Scholar 

  22. Stellwagen, A.E., Haimberger, Z.W., Veatch, J.R. & Gottschling, D.E. Ku interacts with telomerase RNA to promote telomere addition at native and broken chromosome ends. Genes Dev. 17, 2384–2395 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Peterson, S.E. et al. The function of a stem-loop in telomerase RNA is linked to the DNA repair protein Ku. Nat. Genet. 27, 64–67 (2001).

    Article  CAS  PubMed  Google Scholar 

  24. Ferguson, B.M. & Fangman, W.L. A position effect on the time of replication origin activation in yeast. Cell 68, 333–339 (1992).

    Article  CAS  PubMed  Google Scholar 

  25. Bertuch, A.A. & Lundblad, V. The Ku heterodimer performs separable activities at double-strand breaks and chromosome termini. Mol. Cell. Biol. 23, 8202–8215 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Livengood, A.J., Zaug, A.J. & Cech, T.R. Essential regions of Saccharomyces cerevisiae telomerase RNA: separate elements for Est1p and Est2p interaction. Mol. Cell. Biol. 22, 2366–2374 (2002).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Larrivee, M., LeBel, C. & Wellinger, R.J. The generation of proper constitutive G-tails on yeast telomeres is dependent on the MRX complex. Genes Dev. 18, 1391–1396 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Schramke, V. et al. RPA regulates telomerase action by providing Est1p access to chromosome ends. Nat. Genet. 36, 46–54 (2004).

    Article  CAS  PubMed  Google Scholar 

  29. Teixeira, M.T., Arneric, M., Sperisen, P. & Lingner, J. Telomere length homeostasis is achieved via a switch between telomerase-extendible and -nonextendible states. Cell 117, 323–335 (2004).

    Article  CAS  PubMed  Google Scholar 

  30. Chan, S.W.-L. & Blackburn, E.H. Telomerase and ATM/Tel1p protect telomeres from nonhomologous end joining. Mol. Cell 11, 1379–1387 (2003).

    Article  CAS  PubMed  Google Scholar 

  31. Prescott, J. & Blackburn, E. Functionally interacting telomerase RNAs in the yeast telomerase complex. Genes Dev. 11, 2790–2800 (1997).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Lin, J.-J. & Zakian, V.A. An in vitro assay for Saccharomyces telomerase requires EST1 . Cell 81, 1127–1135 (1995).

    Article  CAS  PubMed  Google Scholar 

  33. Hughes, T.R., Evans, S.K., Weilbaecher, R.G. & Lundblad, V. The Est3 protein is a subunit of yeast telomerase. Curr. Biol. 10, 809–812 (2000).

    Article  CAS  PubMed  Google Scholar 

  34. Zhou, J., Hidaka, K. & Futcher, B. The Est1 subunit of yeast telomerase binds the Tlc1 telomerase RNA. Mol. Cell. Biol. 20, 1947–1955 (2000).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Lundblad, V. & Szostak, J.W. A mutant with a defect in telomere elongation leads to senescence in yeast. Cell 57, 633–643 (1989).

    Article  CAS  PubMed  Google Scholar 

  36. Qi, H. & Zakian, V.A. The Saccharomyces telomere-binding protein Cdc13p interacts with both the catalytic subunit of DNA polymerase α and the telomerase-associated Est1 protein. Genes Dev. 14, 1777–1788 (2000).

    CAS  PubMed  PubMed Central  Google Scholar 

  37. Evans, S.K. & Lundblad, V. The Est1 subunit of Saccharomyces cerevisiae telomerase makes multiple contributions to telomere length maintenance. Genetics 162, 1101–1115 (2002).

    CAS  PubMed  PubMed Central  Google Scholar 

  38. Evans, S.K. & Lundblad, V. Est1 and Cdc13 as comediators of telomerase access. Science 286, 117–120 (1999).

    Article  CAS  PubMed  Google Scholar 

  39. Pennock, E., Buckley, K. & Lundblad, V. Cdc13 delivers separate complexes to the telomere for end protection and replication. Cell 104, 387–396 (2001).

    Article  CAS  PubMed  Google Scholar 

  40. d'Adda di Fagagna, F. et al. Effects of DNA nonhomologous end-joining factors on telomere length and chromosomal stability in mammalian cells. Curr. Biol. 11, 1192–1196 (2001).

    Article  CAS  PubMed  Google Scholar 

  41. Hsu, H.L., Gilley, D., Blackburn, E.H. & Chen, D.J. Ku is associated with the telomere in mammals. Proc. Natl. Acad. Sci. USA 96, 12454–12458 (1999).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Myung, K. et al. Regulation of telomere length and suppression of genomic instability in human somatic cells by Ku86. Mol. Cell. Biol. 24, 5050–5059 (2004).

    Article  PubMed  PubMed Central  Google Scholar 

  43. Chai, W., Ford, L.P., Lenertz, L., Wright, W.E. & Shay, J.W. Human Ku70/80 associates physically with telomerase through interaction with hTERT. J. Biol. Chem. 277, 47242–47247 (2002).

    Article  CAS  PubMed  Google Scholar 

  44. Sikorski, R.S. & Hieter, P. A system of shuttle vectors and yeast host strains designed for efficient manipulation of DNA in Saccharomyces cerevisiae . Genetics 122, 19–27 (1989).

    CAS  PubMed  PubMed Central  Google Scholar 

  45. Sandell, L.L., Gottschling, D.E. & Zakian, V.A. Transcription of a yeast telomere alleviates telomere position effect without affecting chromosome stability. Proc. Natl. Acad. Sci. USA 91, 12061–12065 (1994).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  46. Tsukamoto, Y., Taggart, A.K.P. & Zakian, V.A. The role of the Mre11–Rad50–Xrs2 complex in telomerase-mediated lengthening of Saccharomyces cerevisiae telomeres. Curr. Biol. 11, 1328–1335 (2001).

    Article  CAS  PubMed  Google Scholar 

  47. Lorenz, M.C. et al. Gene disruption with PCR products in Saccharomyces cerevisiae . Gene 158, 113–117 (1995).

    Article  CAS  PubMed  Google Scholar 

  48. Friedman, K.L. & Cech, T.R. Essential functions of amino-terminal domains in the yeast telomerase catalytic subunit revealed by selection for viable mutants. Genes Dev. 13, 2863–2874 (1999).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

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Acknowledgements

We thank S. Dunaway, L. Goudsouzian, A. Ivessa, M. Sabourin, and L. Vega for critical reading of the manuscript. We thank A. Chan for technical assistance and D. Gottschling and A. Stellwagen for strains. This work was supported by US National Institutes of Health (NIH) grant GM43265. T.S.F. is a Leukemia and Lymphoma Society Research Fellow. A.K.P.T was supported in part by a postdoctoral fellowship from the Susan G. Komen Breast Cancer Foundation and also NIH grant T32 CA09528.

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Correspondence to Virginia A Zakian.

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Supplementary information

Supplementary Fig. 1

Telomere phenotypes of Myc-tagged yKu80p strain. (PDF 321 kb)

Supplementary Fig. 2

Est2p telomere association in G1 and late S phase is also affected in yku80-135i cells. (PDF 279 kb)

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Fisher, T., Taggart, A. & Zakian, V. Cell cycle-dependent regulation of yeast telomerase by Ku. Nat Struct Mol Biol 11, 1198–1205 (2004). https://doi.org/10.1038/nsmb854

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