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:

Reversible disassembly of somatic nucleoli by the germ cell proteins FRGY2a and FRGY2b

Nature Cell Biology volume 5, pages 205–210 (2003)Cite this article

Abstract

Egg cytoplasm has the capability to reprogramme differentiated somatic nuclei, as shown by nuclear transplantation in animal cloning1,2. The nucleoli of donor nuclei are rapidly disassembled on injection into interphase eggs and are correctly reassembled when donor transcription initiates in the early embryos of frogs and mammals, recapitulating the physiological nucleolar dynamics of early embryogenesis3,4,5,6. This is one of the most remarkable structural reorganizations of somatic nuclei in nuclear cloning. Despite the long history of nuclear cloning, almost nothing is known about the molecular mechanism of nucleolar disassembly in egg cytoplasm. Here we show that the Xenopus germ cell proteins FRGY2a and FRGY2b7,8,9 reversibly disassemble somatic nucleoli in egg cytoplasm, independently of continuing ribosomal RNA transcription. The carboxy-terminal domain of FRGY2a, which localizes to the nucleoli, is sufficient for nucleolar disassembly in transfected cells. Our results show that a single protein fragment can trigger reversible disassembly of the complex nucleolar structure.

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

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

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

Figure 1: Xenopus egg extract disassembles somatic nucleoli.
Figure 2: Egg FRGY2a/b and rFRGY2a disassemble somatic nucleoli.
Figure 3: Dispersal of B23 in living cells by rFRGY2a.
Figure 4: Restoration of disassembled nucleoli in oocyte extract.

Similar content being viewed by others

References

  1. Solter, D. Mammalian cloning: advances and limitations. Nature Rev. Genet. 1, 199–207 (2000).

    Article  CAS  PubMed  Google Scholar 

  2. Rideout, I.W., Eggan, K. & Jaenisch, R. Nuclear cloning and epigenetic reprogramming of the genome. Science 293, 1093–1098 (2001).

    Article  CAS  Google Scholar 

  3. Gurdon, J.B. Cytoplasmic regulation of RNA synthesis and nucleolus formation in developing embryos of Xenopus laevis. J. Mol. Biol. 12, 27–35 (1965).

    Article  CAS  PubMed  Google Scholar 

  4. Ouhibi, N., Fulka, J. Jr, Kanka, J. & Moor, R.M. Nuclear transplantation of ectodermal cells in pig oocytes: ultrastructure and radiography. Mol. Reprod. Dev. 44, 533–539 (1996).

    Article  CAS  PubMed  Google Scholar 

  5. Kanka, J. et al. Transcriptional activity and nucleolar ultrastructure of embryonic rabbit nuclei after transplantation to enucleated oocytes. Mol. Reprod. Dev. 43, 135–144 (1996).

    Article  CAS  PubMed  Google Scholar 

  6. Kanka, J., Smith, S.D., Soloy, E., Holm, P. & Callesen, H. Nucleolar ultrastructure in bovine nuclear transfer embryos. Mol. Reprod. Dev. 52, 253–263 (1999).

    Article  CAS  PubMed  Google Scholar 

  7. Spirin, A. in Translational Control (eds Hershey, J., Mathews, M. & Sonenberg, N.) 319–334 (Cold Spring Harbor Laboratory Press, 1996).

    Google Scholar 

  8. Sommerville, J. & Ladomery, M. Transcription and masking of mRNA in germ cells: involvement of Y-box proteins. Chromosoma 104, 469–478 (1996).

    CAS  PubMed  Google Scholar 

  9. Graumann, P.L. & Marahiel, M.A. A superfamily of proteins that contain the cold-shock domain. Trends Biochem. Sci. 23, 286–290 (1998).

    Article  CAS  PubMed  Google Scholar 

  10. Verheggen, C., Le Panse, S., Almouzni, G. & Hernandez-Verdun, D. Presence of pre-rRNAs before activation of polymerase I transcription in the building process of nucleoli during early development of Xenopus laevis. J. Cell. Biol. 142, 1167–1180 (1998).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Gurdon, J.B. Changes in somatic cell nuclei inserted into growing and maturing amphibian oocytes. J. Embryol. Exp. Morphol. 20, 401–414 (1968).

    CAS  PubMed  Google Scholar 

  12. Simard, R. The nucleus: action of chemical and physical agents. Int. Rev. Cytol. 28, 169–211 (1970).

    Article  CAS  PubMed  Google Scholar 

  13. Goessens, G. Nucleolar structure. Int. Rev. Cytol. 87, 107–158 (1984).

    Article  CAS  PubMed  Google Scholar 

  14. Kikyo, N., Wade, P.A., Guschin, D., Ge, H. & Wolffe, A.P. Active remodeling of somatic nuclei in egg cytoplasm by the nucleosomal ATPase ISWI. Science 289, 2360–2362 (2000).

    Article  CAS  Google Scholar 

  15. Hernandez-Verdun, D., Roussel, P. & Gebrane-Younes, J. Emerging concepts of nucleolar assembly. J. Cell Sci. 115, 2265–2270 (2002).

    CAS  PubMed  Google Scholar 

  16. Murray, M.T., Krohne, G. & Franke, W.W. Different forms of soluble cytoplasmic mRNA binding proteins and particles in Xenopus laevis oocytes and embryos. J. Cell Biol. 112, 1–11 (1991).

    Article  CAS  PubMed  Google Scholar 

  17. Murray, M.T., Schiller, D.L. & Franke, W.W. Sequence analysis of cytoplasmic mRNA-binding proteins of Xenopus oocytes identifies a family of RNA-binding proteins. Proc. Natl Acad. Sci. USA 89, 11–15 (1992).

    Article  CAS  PubMed  Google Scholar 

  18. Bouvet, P., Matsumoto, K. & Wolffe, A.P. Sequence-specific RNA recognition by the Xenopus Y-box proteins. An essential role for the cold shock domain. J. Biol. Chem. 270, 28297–28303 (1995).

    Article  CAS  PubMed  Google Scholar 

  19. Yurkova, M.S. & Murray, M.T. A translation regulatory particle containing the Xenopus oocyte Y box protein mRNP3+4. J. Biol. Chem. 272, 10870–10876 (1997).

    Article  CAS  PubMed  Google Scholar 

  20. Kwon, Y.K., Murray, M.T. & Hecht, N.B. Proteins homologous to the Xenopus germ cell-specific RNA-binding proteins p54/p56 are temporally expressed in mouse male germ cells. Dev. Biol. 158, 99–100 (1993).

    Article  CAS  PubMed  Google Scholar 

  21. Matsumoto, K., Meric, F. & Wolffe, A.P. Translational repression dependent on the interaction of the Xenopus Y-box protein FRGY2 with mRNA. Role of the cold shock domain, tail domain, and selective RNA sequence recognition. J. Biol. Chem. 271, 22706–22712 (1996).

    Article  CAS  PubMed  Google Scholar 

  22. Ochs, R.L. Methods used to study structure and function of the nucleolus. Methods Cell Biol. 53, 303–321 (1998).

    Article  CAS  PubMed  Google Scholar 

  23. Sirri, V., Hernandez-Verdun, D. & Roussel, P. Cyclin-dependent kinases govern formation and maintenance of the nucleolus. J. Cell Biol. 156, 969–981 (2002).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Carmo-Fonseca, M., Mendes-Soares, L. & Campos, I. To be or not to be in the nucleolus. Nature Cell Biol. 2, E107–E112 (2000).

    Article  CAS  PubMed  Google Scholar 

  25. Wong, J.M., Kusdra, L. & Collins, K. Subcellular shuttling of human telomerase induced by transformation and DNA damage. Nature Cell Biol. 4, 731–736 (2002).

    Article  CAS  PubMed  Google Scholar 

  26. Schmidt-Zachmann, M.S., Hugle, B., Scheer, U. & Franke, W.W. Identification and localization of a novel nucleolar protein of high molecular weight by a monoclonal antibody. Exp. Cell Res. 153, 327–346 (1984).

    Article  CAS  PubMed  Google Scholar 

  27. Cairns, C. & McStay, B. HMG box 4 is the principal determinant of species specificity in the RNA polymerase I transcription factor UBF. Nucleic Acids Res. 23, 4583–4590 (1995).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Spector, D.L., Goldman, R.D. & Leinwand, L.A. in Cells, A Laboratory Manual 111.111–111.145 (Cold Spring Harbor Laboratory Press, New York, 1997).

    Google Scholar 

  29. Darzynkiewicz, Z. Differential staining of DNA and RNA in intact cells and isolated cell nuclei with acridine orange. Methods Cell Biol. 33, 285–298 (1990).

    Article  CAS  PubMed  Google Scholar 

  30. Sambrook, J. & Russell, D.W. in Molecular Cloning, A Laboratory Manual 17.23–17.29 (Cold Spring Harbor Laboratory Press, New York, 2001).

    Google Scholar 

Download references

Acknowledgements

We thank M. Schmidt-Zachmann, M. O. J. Olson, B. McStay and J. G. Gall for antibodies and DNA probes; S. L. Erlandsen and G. Ahlstrand for electron microscopy; L. Higgins and T. Krick for mass spectrometry; and C. M. Verfaille, M. O. J. Olson and R. Kuriyama for comments. J.F. is supported by the University of Minnesota's undergraduate research opportunities programme (UROP). This work was partly supported by the Minnesota Medical Foundation. N.K. wanted to show this work to Alan P. Wolffe, his previous mentor who first cloned FRGY2a but who passed away in a tragic accident on 26 May 2001, not knowing its nucleolar disassembly activity.

Author information

Author notes

  1. Koichi Gonda and Jason Fowler: These authors contributed equally to this work

Authors and Affiliations

  1. Stem Cell Institute and Division of Hematology, Department of Medicine, Oncology and Transplantation, University of Minnesota, Mayo Mail Code 716, 420 Delaware Street, Minneapolis, 55455, Minnesota, USA

    Koichi Gonda, Jason Fowler, Nobuko Katoku-Kikyo, Jennifer Haroldson, Justin Wudel & Nobuaki Kikyo

Authors
  1. Koichi Gonda
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Jason Fowler
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Nobuko Katoku-Kikyo
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Jennifer Haroldson
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Justin Wudel
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Nobuaki Kikyo
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Nobuaki Kikyo.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Figures

Figure S1 Nucleolar disassembly by FRGY2 proteins. (PDF 115 kb)

Figure S2 Electron micrographs of disassembledand reassembled nucleoli.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Gonda, K., Fowler, J., Katoku-Kikyo, N. et al. Reversible disassembly of somatic nucleoli by the germ cell proteins FRGY2a and FRGY2b. Nat Cell Biol 5, 205–210 (2003). https://doi.org/10.1038/ncb939

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ncb939

This article is cited by

Search

Advanced 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