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:

Distinct functions for the two importin subunits in nuclear protein import

Abstract

THE import of nuclear proteins proceeds through the nuclear pore complex and requires nuclear localization signals (NLSs)1,2, energy3,4 and soluble factors5, namely importin-α(Mr 60K)6-12,28, importin-β (90K)8-11,13 and Ran14,15. Importin-α is primarily responsible for NLS recognition6-12,29 and is a member of a protein family that includes the essential yeast nuclear pore protein SRPlp (ref. 16). As the first event, the complex of importin-α and importin-β binds the import substrate in the cytosol8,9. Here we show that this nuclear pore targeting complex initially docks as a single entity to the nuclear pore via importin-β. Then the energy-dependent, Ran-mediated translocation through the pore results in the accumulation of import substrate and importin-α in the nucleus. In contrast, importin-β accumulates at the nuclear envelope, but not in the nucleoplasm. Immunoelectron microscopy detects importin-β on both sides of the nuclear pore. This suggests that the nuclear pore targeting complex might move as a single entity from its initial docking site through the central part of the nuclear pore before it disassembles on the nucleoplasmic side.

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

Similar content being viewed by others

References

  1. Dingwall, C., Sharnick, S. V. & Laskey, R. A. Cell 30, 449–458 (1982).

    Article  CAS  Google Scholar 

  2. Kalderon, D., Roberts, B. L., Richardson, W. D. & Smith, A. E. Cell 39, 499–509 (1984).

    Article  CAS  Google Scholar 

  3. Newmeyer, D. D. & Forbes, D. J. Cell 52, 641–653 (1988).

    Article  CAS  Google Scholar 

  4. Richardson, W. D., Mills, A. D., Dilworth, S. M., Laskey, R. A. & Dingwall, C. Cell 52, 655–664 (1988).

    Article  CAS  Google Scholar 

  5. Adam, S. A., Sterne-Marr, R. & Gerace, L. J. Cell Biol. 111, 807–816 (1990).

    Article  CAS  Google Scholar 

  6. Adam, S. A. & Gerace, L. Cell 66, 837–847 (1991).

    Article  CAS  Google Scholar 

  7. Görlich, D., Prehn, S., Laskey, R. A. & Hartmann, E. Cell 79, 767–778 (1994).

    Article  Google Scholar 

  8. Görlich, D. et al. Curr. Biol. 5, 383–392 (1995).

    Article  Google Scholar 

  9. Imamoto, N., Tachibana, T., Matsubae, M. & Yoneda, Y. J. biol. Chem. 270, 8559–8565 (1995).

    Article  CAS  Google Scholar 

  10. Moroianu, J., Blobel, G. & Radu, A. Proc. natn. Acad. Sci. U.S.A. 92, 2008–2011 (1995).

    Article  ADS  CAS  Google Scholar 

  11. Radu, A., Blobel, G. & Moore, M. S. Proc. natn. Acad. Sci. U.S.A. 92, 1769–1773 (1995).

    Article  ADS  CAS  Google Scholar 

  12. Weis, K., Mattaj, I. W. & Lamond, A. I. Science 268, 1049–1051 (1995).

    Article  ADS  CAS  Google Scholar 

  13. Chi, N. C., Adam, E. J. H. & Adam, S. A. J. Cell Biol. 130, 265–274 (1995).

    Article  CAS  Google Scholar 

  14. Moore, M. S. & Blobel, G. Nature 365, 661–663 (1993).

    Article  ADS  CAS  Google Scholar 

  15. Melchior, F., Paschal, B., Evans, J. & Gerace, L. J. Cell Biol. 123, 1649–1659 (1993).

    Article  CAS  Google Scholar 

  16. Yano, R., Oakes, M., Yamaghishi, M., Dodd, J. A. & Nomura, M. Molec. cell. Biol. 12, 5640–5651 (1992).

    Article  CAS  Google Scholar 

  17. Moore, M. S. & Biobel, G. Proc. natn. Acad. Sci. U.S.A. 91, 10212–10216 (1994).

    Article  ADS  CAS  Google Scholar 

  18. Paschal, B. M. & Gerace, L. J. Cell Biol. 129, 925–937 (1995).

    Article  CAS  Google Scholar 

  19. Adam, S. A., Lobl, T. J., Mitchell, M. A. & Gerace, L. Nature 337, 276–279 (1989).

    Article  ADS  CAS  Google Scholar 

  20. Bischoff, F. R. & Ponstingl, H. Proc. natn. Acad. Sci. U.S.A. 88, 10830–10834 (1991).

    Article  ADS  CAS  Google Scholar 

  21. Ren, M. D., Drivas, G., Deustachio, P. & Rush, M. G. J. Cell Biol. 120, 313–323 (1993).

    Article  CAS  Google Scholar 

  22. Moroianu, J. & Blobel, G. Proc. natn. Acad. Sci. U.S.A. 92, 4318–4322 (1995).

    Article  ADS  CAS  Google Scholar 

  23. Schmidt-Zachmann, M. S., Dargemont, C., Kuhn, L. C. & Nigg, E. A. Cell 74, 493–504 (1993).

    Article  CAS  Google Scholar 

  24. Azuma, Y., Tabb, M. M., Vu, L. & Nomura, M. Proc. natn. Acad. Sci. U.S.A. 5159–5163 (1995).

  25. Harlow, E. & Lane, D. Antibodies: A Laboratory Manual (Cold Spring Harbor Laboratory, New York, 1988).

    Google Scholar 

  26. Tokuyasu, K. Histochem. J. 21, 163–171 (1989).

    Article  CAS  Google Scholar 

  27. Griffiths, G. in Fine Structure Immunocytochemistry 137–203 (Springer, Berlin, 1993).

    Google Scholar 

  28. Imamoto, N. et al. EMBO J. 14, 36717–36726 (1995).

    Article  Google Scholar 

  29. Moroianu, J., Hijikata, M., Blobel, G. & Radu, A. Proc. natn. Acad. Sci. U.S.A. 92, 6532–6536 (1995).

    Article  ADS  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Görlich, D., Vogel, F., Mills, A. et al. Distinct functions for the two importin subunits in nuclear protein import. Nature 377, 246–248 (1995). https://doi.org/10.1038/377246a0

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/377246a0

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