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Genomic mapping of single-stranded DNA in hydroxyurea-challenged yeasts identifies origins of replication

Abstract

During DNA replication one or both strands transiently become single stranded: first at the sites where initiation of DNA synthesis occurs (known as origins of replication) and subsequently on the lagging strands of replication forks as discontinuous Okazaki fragments are generated. We report a genome-wide analysis of single-stranded DNA (ssDNA) formation in the presence of hydroxyurea during DNA replication in wild-type and checkpoint-deficient rad53 Saccharomyces cerevisiae cells. In wild-type cells, ssDNA was first observed at a subset of replication origins and later 'migrated' bi-directionally, suggesting that ssDNA formation is associated with continuously moving replication forks. In rad53 cells, ssDNA was observed at virtually every known origin, but remained there over time, suggesting that replication forks stall. Telomeric regions seemed to be particularly sensitive to the loss of Rad53 checkpoint function. Replication origins in Schizosaccharomyces pombe were also mapped using our method.

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Figure 1: Outline of experimental procedures.
Figure 2: Dynamics of ssDNA formation in wild-type (WT) and rad53 cells.
Figure 3: Elevated levels of ssDNA at telomeric regions.
Figure 4: Identification of new origins from the ssDNA profiles of rad53 cells.
Figure 5: ssDNA profiles of S. pombe chromosomes
Figure 6: Comparison of the distributions of inter-origin distances in S. cerevisiae (cross-hatched bars) and S. pombe (solid black bars).

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References

  1. Nyberg, K. A., Michelson, R. J., Putnam, C. W. & Weinert, T. A. Toward maintaining the genome: DNA damage and replication checkpoints. Annu. Rev. Genet. 36, 617–656 (2002).

    Article  CAS  Google Scholar 

  2. Toueille, M. & Hubscher, U. Regulation of the DNA replication fork: a way to fight genomic instability. Chromosoma 113, 113–125 (2004).

    Article  CAS  Google Scholar 

  3. Early, A., Drury, L. S. & Diffley, J. F. Mechanisms involved in regulating DNA replication origins during the cell cycle and in response to DNA damage. Philos. Trans. R. Soc. Lond. B Biol. Sci. 359, 31–38 (2004).

    Article  CAS  Google Scholar 

  4. Sogo, J. M., Lopes, M. & Foiani, M. Fork reversal and ssDNA accumulation at stalled replication forks owing to checkpoint defects. Science 297, 599–602 (2002).

    Article  CAS  Google Scholar 

  5. Raghuraman, M. K. et al. Replication dynamics of the yeast genome. Science 294, 115–121 (2001).

    Article  CAS  Google Scholar 

  6. Santocanale, C. & Diffley, J. F. A Mec1- and Rad53-dependent checkpoint controls late-firing origins of DNA replication. Nature 395, 615–618 (1998).

    Article  CAS  Google Scholar 

  7. Shirahige, K. et al. Regulation of DNA-replication origins during cell-cycle progression. Nature 395, 618–621 (1998).

    Article  CAS  Google Scholar 

  8. Tercero, J. A. & Diffley, J. F. Regulation of DNA replication fork progression through damaged DNA by the Mec1–Rad53 checkpoint. Nature 412, 553–557 (2001).

    Article  CAS  Google Scholar 

  9. Lopes, M et al. The DNA replication checkpoint response stabilizes stalled replication forks. Nature 412, 557–561 (2001).

    Article  CAS  Google Scholar 

  10. Longhese, M. P., Paciotti, V., Neecke, H. & Lucchini, G. Checkpoint proteins influence telomeric silencing and length maintenance in budding yeast. Genetics 155, 1577–1591 (2000).

    CAS  PubMed  PubMed Central  Google Scholar 

  11. Jia, X., Weinert, T. & Lydall, D. Mec1 and Rad53 inhibit formation of single-stranded DNA at telomeres of Saccharomyces cerevisiae cdc13-1 mutants. Genetics 166, 753–764 (2004).

    Article  CAS  Google Scholar 

  12. MacAlpine, D. & Bell, S. A genomic view of eukaryotic DNA replication. Chromosome Res. 13, 309–326 (2005).

    Article  CAS  Google Scholar 

  13. Wyrick, J. J. et al. Genome-wide distribution of ORC and MCM proteins in S. cerevisiae: high-resolution mapping of replication origins. Science 294, 2357–2360 (2001).

    Article  CAS  Google Scholar 

  14. Poloumienko, A., Dershowitz, A., De, J. & Newlon, C. S. Completion of replication map of Saccharomyces cerevisiae chromosome III. Mol. Biol. Cell 12, 3317–3327 (2001).

    Article  CAS  Google Scholar 

  15. Yabuki, N., Terashima, H. & Kitada, K. Mapping of early firing origins on a replication profile of budding yeast. Genes Cells 7, 781–789 (2002).

    Article  CAS  Google Scholar 

  16. Friedman, K. L., Brewer, B. J. & Fangman, W. L. Replication profile of Saccharomyces cerevisiae chromosome VI. Genes Cells 2, 667–678 (1997).

    Article  CAS  Google Scholar 

  17. Murakami, H. & Okayama, H. A kinase from fission yeast responsible for blocking mitosis in S phase. Nature 374, 817–819 (1995).

    Article  CAS  Google Scholar 

  18. Kumar, S. & Huberman, J. A. On the slowing of S phase in response to DNA damage in fission yeast. J. Biol. Chem. 279, 43574–43580 (2004).

    Article  CAS  Google Scholar 

  19. Segurado, M., de Luis, A. & Antequera F. Genome-wide distribution of DNA replication origins at A+T-rich islands in Schizosaccharomyces pombe. EMBO Rep. 11, 1048–1053 (2003).

    Article  Google Scholar 

  20. Kim, S. & Huberman, J. A. Regulation of replication timing in fission yeast. EMBO J. 20, 6115–6126 (2001).

    Article  CAS  Google Scholar 

  21. Patel, P. K. et al. DNA replication origins fire stochastically in fission yeast. Mol. Biol. Cell 17, 308–316 (2006).

    Article  CAS  Google Scholar 

  22. Sun, Z. et al. Spk1–Rad53 is regulated by Mec1-dependent protein phosphorylation in DNA replication and damage checkpoint pathways. Genes Dev. 10, 395–406 (1996).

    Article  CAS  Google Scholar 

  23. Pellicioli, A. et al. Activation of Rad53 kinase in response to DNA damage and its effect in modulating phosphorylation of the lagging strand DNA polymerase. EMBO J. 18, 6561–6572 (1999).

    Article  CAS  Google Scholar 

  24. Hutter, K. J. & Eipel, H. E. Microbial determinations by flow cytometry. J. Gen. Microbiol. 113, 369–375 (1979).

    Article  CAS  Google Scholar 

  25. Brewer, B. J., Lockshon, D. & Fangman, W. L. The arrest of replication forks in the rDNA of yeast occurs independently of transcription. Cell 71, 267–276 (1992).

    Article  CAS  Google Scholar 

  26. Huberman, J. A. et al. The in vivo replication origin of the yeast 2 microns plasmid. Cell 51, 473–481 (1987).

    Article  CAS  Google Scholar 

  27. Garvik, B., Carson, M. & Hartwell, L. Single-stranded DNA arising at telomeres in cdc13 mutants may constitute a specific signal for the RAD9 checkpoint. Mol. Cell Biol. 15, 6128–6138 (1995).

    Article  CAS  Google Scholar 

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Acknowledgements

We wish to thank the Fangman–Brewer laboratory members for support and helpful discussions. We also acknowledge G. Findlay for helping with the construction of the rad53 exo1 double mutant and for critically reading the manuscript. We are grateful to M. Foiani for providing the pCH8 plasmid containing the rad53K227A mutation and G. D'Urso for S. pombe strains and helpful discussions. We also thank the staff at the Center for Expression Arrays. Seattle for their service of microarray slide hybridizations and scanning. We extend our gratitude to M. Thornquist, J. Haessler and U. Khan for helpful advice. This work was supported by National Institute of General Medical Sciences (NIGMS) grant 18926 to W.L.F., B.J.B. and M.K.R. W.F. was supported by a Ruth L. Kirschstein Postdoctoral Fellowship from the National Institutes of Health (NIH).

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Correspondence to Bonita J. Brewer.

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Supplementary Figures S1, S2, S3. Tables S1 and S2 (PDF 3577 kb)

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Feng, W., Collingwood, D., Boeck, M. et al. Genomic mapping of single-stranded DNA in hydroxyurea-challenged yeasts identifies origins of replication. Nat Cell Biol 8, 148–155 (2006). https://doi.org/10.1038/ncb1358

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