Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1993 Nov 2;123(4):785–798. doi: 10.1083/jcb.123.4.785

Reconstitution of nuclear protein transport with semi-intact yeast cells

PMCID: PMC2200159  PMID: 8227140

Abstract

We have developed an in vitro nuclear protein import reaction from semi- intact yeast cells. The reaction uses cells that have been permeabilized by freeze-thaw after spheroplast formation. Electron microscopic analysis and antibody-binding experiments show that the nuclear envelope remains intact but the plasma membrane is perforated. In the presence of ATP and cytosol derived from yeast or mammalian cells, a protein containing the nuclear localization sequence (NLS) of SV40 large T-antigen is transported into the nucleus. Proteins with mutant NLSs are not imported. In the absence of cytosol, binding of NLS- containing proteins occurs at the nuclear envelope. N-ethylmaleimide treatment of the cytosol as well as antibodies to the nuclear pore protein Nsp1 inhibit import but not binding to the nuclear envelope. Yeast mutants defective in nuclear protein transport were tested in the in vitro import reaction. Semi-intact cells from temperature-sensitive nsp1 mutants failed to import but some binding to the nuclear envelope was observed. On the other hand, no binding and thus no import into nuclei was observed in semi-intact nsp49 cells which are mutated in another nuclear pore protein. Np13 mutants, which are defective for nuclear protein import in vivo, were also deficient in the binding step under the in vitro conditions. Thus, the transport defect in these mutants is at the level of the nucleus and the point at which nuclear transport is blocked can be defined.

Full Text

The Full Text of this article is available as a PDF (6.7 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adam S. A., Gerace L. Cytosolic proteins that specifically bind nuclear location signals are receptors for nuclear import. Cell. 1991 Sep 6;66(5):837–847. doi: 10.1016/0092-8674(91)90431-w. [DOI] [PubMed] [Google Scholar]
  2. Adam S. A., Lobl T. J., Mitchell M. A., Gerace L. Identification of specific binding proteins for a nuclear location sequence. Nature. 1989 Jan 19;337(6204):276–279. doi: 10.1038/337276a0. [DOI] [PubMed] [Google Scholar]
  3. Adam S. A., Marr R. S., Gerace L. Nuclear protein import in permeabilized mammalian cells requires soluble cytoplasmic factors. J Cell Biol. 1990 Sep;111(3):807–816. doi: 10.1083/jcb.111.3.807. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Akey C. W., Goldfarb D. S. Protein import through the nuclear pore complex is a multistep process. J Cell Biol. 1989 Sep;109(3):971–982. doi: 10.1083/jcb.109.3.971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Baker D., Hicke L., Rexach M., Schleyer M., Schekman R. Reconstitution of SEC gene product-dependent intercompartmental protein transport. Cell. 1988 Jul 29;54(3):335–344. doi: 10.1016/0092-8674(88)90196-1. [DOI] [PubMed] [Google Scholar]
  6. Bossie M. A., DeHoratius C., Barcelo G., Silver P. A mutant nuclear protein with similarity to RNA binding proteins interferes with nuclear import in yeast. Mol Biol Cell. 1992 Aug;3(8):875–893. doi: 10.1091/mbc.3.8.875. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Bossie M. A., Silver P. A. Movement of macromolecules between the cytoplasm and the nucleus in yeast. Curr Opin Genet Dev. 1992 Oct;2(5):768–774. doi: 10.1016/s0959-437x(05)80137-6. [DOI] [PubMed] [Google Scholar]
  8. Breeuwer M., Goldfarb D. S. Facilitated nuclear transport of histone H1 and other small nucleophilic proteins. Cell. 1990 Mar 23;60(6):999–1008. doi: 10.1016/0092-8674(90)90348-i. [DOI] [PubMed] [Google Scholar]
  9. Carmo-Fonseca M., Kern H., Hurt E. C. Human nucleoporin p62 and the essential yeast nuclear pore protein NSP1 show sequence homology and a similar domain organization. Eur J Cell Biol. 1991 Jun;55(1):17–30. [PubMed] [Google Scholar]
  10. Conradt B., Shaw J., Vida T., Emr S., Wickner W. In vitro reactions of vacuole inheritance in Saccharomyces cerevisiae. J Cell Biol. 1992 Dec;119(6):1469–1479. doi: 10.1083/jcb.119.6.1469. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Dabauvalle M. C., Schulz B., Scheer U., Peters R. Inhibition of nuclear accumulation of karyophilic proteins in living cells by microinjection of the lectin wheat germ agglutinin. Exp Cell Res. 1988 Jan;174(1):291–296. doi: 10.1016/0014-4827(88)90163-2. [DOI] [PubMed] [Google Scholar]
  12. Davis L. I., Fink G. R. The NUP1 gene encodes an essential component of the yeast nuclear pore complex. Cell. 1990 Jun 15;61(6):965–978. doi: 10.1016/0092-8674(90)90062-j. [DOI] [PubMed] [Google Scholar]
  13. Featherstone C., Darby M. K., Gerace L. A monoclonal antibody against the nuclear pore complex inhibits nucleocytoplasmic transport of protein and RNA in vivo. J Cell Biol. 1988 Oct;107(4):1289–1297. doi: 10.1083/jcb.107.4.1289. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Finlay D. R., Forbes D. J. Reconstitution of biochemically altered nuclear pores: transport can be eliminated and restored. Cell. 1990 Jan 12;60(1):17–29. doi: 10.1016/0092-8674(90)90712-n. [DOI] [PubMed] [Google Scholar]
  15. Finlay D. R., Newmeyer D. D., Price T. M., Forbes D. J. Inhibition of in vitro nuclear transport by a lectin that binds to nuclear pores. J Cell Biol. 1987 Feb;104(2):189–200. doi: 10.1083/jcb.104.2.189. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Garcia-Bustos J. F., Wagner P., Hall M. N. Yeast cell-free nuclear protein import requires ATP hydrolysis. Exp Cell Res. 1991 Jan;192(1):213–219. doi: 10.1016/0014-4827(91)90178-w. [DOI] [PubMed] [Google Scholar]
  17. Garcia-Bustos J., Heitman J., Hall M. N. Nuclear protein localization. Biochim Biophys Acta. 1991 Mar 7;1071(1):83–101. doi: 10.1016/0304-4157(91)90013-m. [DOI] [PubMed] [Google Scholar]
  18. Goldfarb D. S., Gariépy J., Schoolnik G., Kornberg R. D. Synthetic peptides as nuclear localization signals. Nature. 1986 Aug 14;322(6080):641–644. doi: 10.1038/322641a0. [DOI] [PubMed] [Google Scholar]
  19. Goldfarb D., Michaud N. Pathways for the nuclear transport of proteins and RNAs. Trends Cell Biol. 1991 Jul;1(1):20–24. doi: 10.1016/0962-8924(91)90065-h. [DOI] [PubMed] [Google Scholar]
  20. Greber U. F., Gerace L. Nuclear protein import is inhibited by an antibody to a lumenal epitope of a nuclear pore complex glycoprotein. J Cell Biol. 1992 Jan;116(1):15–30. doi: 10.1083/jcb.116.1.15. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Gu Z., Moerschell R. P., Sherman F., Goldfarb D. S. NIP1, a gene required for nuclear transport in yeast. Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10355–10359. doi: 10.1073/pnas.89.21.10355. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Hurt E. C. A novel nucleoskeletal-like protein located at the nuclear periphery is required for the life cycle of Saccharomyces cerevisiae. EMBO J. 1988 Dec 20;7(13):4323–4334. doi: 10.1002/j.1460-2075.1988.tb03331.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Imamoto-Sonobe N., Matsuoka Y., Semba T., Okada Y., Uchida T., Yoneda Y. A protein recognized by antibodies to Asp-Asp-Asp-Glu-Asp shows specific binding activity to heterogeneous nuclear transport signals. J Biol Chem. 1990 Sep 25;265(27):16504–16508. [PubMed] [Google Scholar]
  24. Imamoto N., Matsuoka Y., Kurihara T., Kohno K., Miyagi M., Sakiyama F., Okada Y., Tsunasawa S., Yoneda Y. Antibodies against 70-kD heat shock cognate protein inhibit mediated nuclear import of karyophilic proteins. J Cell Biol. 1992 Dec;119(5):1047–1061. doi: 10.1083/jcb.119.5.1047. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Kalderon D., Roberts B. L., Richardson W. D., Smith A. E. A short amino acid sequence able to specify nuclear location. Cell. 1984 Dec;39(3 Pt 2):499–509. doi: 10.1016/0092-8674(84)90457-4. [DOI] [PubMed] [Google Scholar]
  26. Kalinich J. F., Douglas M. G. In vitro translocation through the yeast nuclear envelope. Signal-dependent transport requires ATP and calcium. J Biol Chem. 1989 Oct 25;264(30):17979–17989. [PubMed] [Google Scholar]
  27. Li R. H., Thomas J. O. Identification of a human protein that interacts with nuclear localization signals. J Cell Biol. 1989 Dec;109(6 Pt 1):2623–2632. doi: 10.1083/jcb.109.6.2623. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Loeb J. D., Davis L. I., Fink G. R. NUP2, a novel yeast nucleoporin, has functional overlap with other proteins of the nuclear pore complex. Mol Biol Cell. 1993 Feb;4(2):209–222. doi: 10.1091/mbc.4.2.209. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Meier U. T., Blobel G. A nuclear localization signal binding protein in the nucleolus. J Cell Biol. 1990 Dec;111(6 Pt 1):2235–2245. doi: 10.1083/jcb.111.6.2235. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Moore M. S., Blobel G. The two steps of nuclear import, targeting to the nuclear envelope and translocation through the nuclear pore, require different cytosolic factors. Cell. 1992 Jun 12;69(6):939–950. doi: 10.1016/0092-8674(92)90613-h. [DOI] [PubMed] [Google Scholar]
  31. Mutvei A., Dihlmann S., Herth W., Hurt E. C. NSP1 depletion in yeast affects nuclear pore formation and nuclear accumulation. Eur J Cell Biol. 1992 Dec;59(2):280–295. [PubMed] [Google Scholar]
  32. Nehrbass U., Kern H., Mutvei A., Horstmann H., Marshallsay B., Hurt E. C. NSP1: a yeast nuclear envelope protein localized at the nuclear pores exerts its essential function by its carboxy-terminal domain. Cell. 1990 Jun 15;61(6):979–989. doi: 10.1016/0092-8674(90)90063-k. [DOI] [PubMed] [Google Scholar]
  33. Nelson M., Silver P. Context affects nuclear protein localization in Saccharomyces cerevisiae. Mol Cell Biol. 1989 Feb;9(2):384–389. doi: 10.1128/mcb.9.2.384. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Newmeyer D. D., Forbes D. J. An N-ethylmaleimide-sensitive cytosolic factor necessary for nuclear protein import: requirement in signal-mediated binding to the nuclear pore. J Cell Biol. 1990 Mar;110(3):547–557. doi: 10.1083/jcb.110.3.547. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Newmeyer D. D., Forbes D. J. Nuclear import can be separated into distinct steps in vitro: nuclear pore binding and translocation. Cell. 1988 Mar 11;52(5):641–653. doi: 10.1016/0092-8674(88)90402-3. [DOI] [PubMed] [Google Scholar]
  36. Newmeyer D. D., Wilson K. L. Egg extracts for nuclear import and nuclear assembly reactions. Methods Cell Biol. 1991;36:607–634. doi: 10.1016/s0091-679x(08)60299-x. [DOI] [PubMed] [Google Scholar]
  37. Nigg E. A., Baeuerle P. A., Lührmann R. Nuclear import-export: in search of signals and mechanisms. Cell. 1991 Jul 12;66(1):15–22. doi: 10.1016/0092-8674(91)90135-l. [DOI] [PubMed] [Google Scholar]
  38. Osborne M. A., Silver P. A. Nucleocytoplasmic transport in the yeast Saccharomyces cerevisiae. Annu Rev Biochem. 1993;62:219–254. doi: 10.1146/annurev.bi.62.070193.001251. [DOI] [PubMed] [Google Scholar]
  39. Richardson W. D., Mills A. D., Dilworth S. M., Laskey R. A., Dingwall C. Nuclear protein migration involves two steps: rapid binding at the nuclear envelope followed by slower translocation through nuclear pores. Cell. 1988 Mar 11;52(5):655–664. doi: 10.1016/0092-8674(88)90403-5. [DOI] [PubMed] [Google Scholar]
  40. Ruohola H., Kabcenell A. K., Ferro-Novick S. Reconstitution of protein transport from the endoplasmic reticulum to the Golgi complex in yeast: the acceptor Golgi compartment is defective in the sec23 mutant. J Cell Biol. 1988 Oct;107(4):1465–1476. doi: 10.1083/jcb.107.4.1465. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Sadler I., Chiang A., Kurihara T., Rothblatt J., Way J., Silver P. A yeast gene important for protein assembly into the endoplasmic reticulum and the nucleus has homology to DnaJ, an Escherichia coli heat shock protein. J Cell Biol. 1989 Dec;109(6 Pt 1):2665–2675. doi: 10.1083/jcb.109.6.2665. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Schimmang T., Tollervey D., Kern H., Frank R., Hurt E. C. A yeast nucleolar protein related to mammalian fibrillarin is associated with small nucleolar RNA and is essential for viability. EMBO J. 1989 Dec 20;8(13):4015–4024. doi: 10.1002/j.1460-2075.1989.tb08584.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Shi Y., Thomas J. O. The transport of proteins into the nucleus requires the 70-kilodalton heat shock protein or its cytosolic cognate. Mol Cell Biol. 1992 May;12(5):2186–2192. doi: 10.1128/mcb.12.5.2186. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Silver P. A. How proteins enter the nucleus. Cell. 1991 Feb 8;64(3):489–497. doi: 10.1016/0092-8674(91)90233-o. [DOI] [PubMed] [Google Scholar]
  45. Silver P., Sadler I., Osborne M. A. Yeast proteins that recognize nuclear localization sequences. J Cell Biol. 1989 Sep;109(3):983–989. doi: 10.1083/jcb.109.3.983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Stochaj U., Bossie M. A., van Zee K., Whalen A. M., Silver P. A. Analysis of conserved binding proteins for nuclear localization sequences. J Cell Sci. 1993 Jan;104(Pt 1):89–95. doi: 10.1242/jcs.104.1.89. [DOI] [PubMed] [Google Scholar]
  47. Stochaj U., Osborne M., Kurihara T., Silver P. A yeast protein that binds nuclear localization signals: purification localization, and antibody inhibition of binding activity. J Cell Biol. 1991 Jun;113(6):1243–1254. doi: 10.1083/jcb.113.6.1243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Stochaj U., Silver P. A. A conserved phosphoprotein that specifically binds nuclear localization sequences is involved in nuclear import. J Cell Biol. 1992 May;117(3):473–482. doi: 10.1083/jcb.117.3.473. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Tollervey D., Lehtonen H., Jansen R., Kern H., Hurt E. C. Temperature-sensitive mutations demonstrate roles for yeast fibrillarin in pre-rRNA processing, pre-rRNA methylation, and ribosome assembly. Cell. 1993 Feb 12;72(3):443–457. doi: 10.1016/0092-8674(93)90120-f. [DOI] [PubMed] [Google Scholar]
  50. Wente S. R., Rout M. P., Blobel G. A new family of yeast nuclear pore complex proteins. J Cell Biol. 1992 Nov;119(4):705–723. doi: 10.1083/jcb.119.4.705. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Wimmer C., Doye V., Grandi P., Nehrbass U., Hurt E. C. A new subclass of nucleoporins that functionally interact with nuclear pore protein NSP1. EMBO J. 1992 Dec;11(13):5051–5061. doi: 10.1002/j.1460-2075.1992.tb05612.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Wolff B., Willingham M. C., Hanover J. A. Nuclear protein import: specificity for transport across the nuclear pore. Exp Cell Res. 1988 Oct;178(2):318–334. doi: 10.1016/0014-4827(88)90402-8. [DOI] [PubMed] [Google Scholar]
  53. Yoneda Y., Imamoto-Sonobe N., Yamaizumi M., Uchida T. Reversible inhibition of protein import into the nucleus by wheat germ agglutinin injected into cultured cells. Exp Cell Res. 1987 Dec;173(2):586–595. doi: 10.1016/0014-4827(87)90297-7. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES