Nuclear Pore: A Bidirectional Transport Machinery



The human nuclear pore complex is a 120 nm structure composed of nearly 1000 protein molecules (multiple copies of nearly 30 different proteins) with a mass of 110–120 MDa. It spans the double membrane of the nuclear envelope and selectively transports both proteins, nucleic acids, and small signaling molecules bidirectionally. The diameter of the channel in the nuclear pore complex is approximately 5 nm in diameter and 45 nm in depth. Selective transport through the nuclear pore complex is mediated by nuclear transport receptors that bind to the cargo to be transported. Importins mediate transport of cargo molecules into the nucleus, whereas exportins facilitate the selective transport of cargo out of the nucleus. Cargoes with a nucleus localization signal are efficiently transported into the nucleus through the nuclear pore complex. The import and export cycles require GTP hydrolysis, and thus the transport process through the nuclear pore complex is energy-dependent. Since the nuclear pore complex is the gateway to the genome, the number of nuclear pore complexes varies during the different stages of the cell cycle. For example, between G1 and G2 phase of the cell cycle, the number of nuclear pore complexes at the nuclear envelope increase to accommodate greater transcriptional demand. Assembly of the nuclear pore complex like other cellular nanomachines is little understood.


Nuclear envelope Selective bidirectional pore Nucleoporins 


  1. 1.
    Callan, H. G., Randall, J. T., & Tomlin, S. G. (1949). An electron microscopy study of the nuclear membrane. Nature, 163, 280.PubMedCrossRefGoogle Scholar
  2. 2.
    Callan, H. G., & Tomlin, S. G. (1950). Experimental studies on amphibian oocyte nuclei. I. Investigation of the structure of the nuclear membrane by means of the electron microscope. Proceedings of the Royal Society of London. Series B-Biological Sciences, 137, 367–378.CrossRefGoogle Scholar
  3. 3.
    Watson, M. L. (1959). Further observations on the nuclear envelope of the animal cell. The Journal of Biophysical and Biochemical Cytology, 6, 147–156.PubMedPubMedCentralCrossRefGoogle Scholar
  4. 4.
    Gerace, L., Ottaviano, Y., & Kondor-Koch, C. (1982). Identification of a major polypeptide of the nuclear pore complex. The Journal of Cell Biology, 95, 826–837.PubMedCrossRefGoogle Scholar
  5. 5.
    Davis, L. I., & Blobel, G. (1986). Identification and characterization of a nuclear pore complex protein. Cell, 45, 699–709.PubMedCrossRefGoogle Scholar
  6. 6.
    Hinshaw, J. E., Carragher, B. O., & Milligan, R. A. (1992). Architecture and design of the nuclear pore complex. Cell, 69, 1133–1141.PubMedCrossRefGoogle Scholar
  7. 7.
    Akey, C. W., & Radermacher, M. (1993). Architecture of the Xenopus nuclear pore complex revealed by three-dimensional cryo-electron microscopy. The Journal of Cell Biology, 122, 1–19.PubMedCrossRefGoogle Scholar
  8. 8.
    Cronshaw, J. M., Krutchinsky, A. N., Zhang, W., Chait, B. T., & Matunis, M. J. (2002). Proteomic analysis of the mammalian nuclear pore complex. The Journal of Cell Biology, 158, 915–927.PubMedPubMedCentralCrossRefGoogle Scholar
  9. 9.
    Stoffler, D., Feja, B., Fahrenkrog, B., Walz, J., Typke, D., & Aebi, U. (2003). Cryo-electron tomography provides novel insights into nuclear pore architecture: Implications for nucleocytoplasmic transport. Journal of Molecular Biology, 328, 119–130.PubMedCrossRefGoogle Scholar
  10. 10.
    Beck, M., Lucic, V., Forster, F., Baumeister, W., & Medalia, O. (2007). Snapshots of nuclear pore complexes in action captured by cryo-electron tomography. Nature, 449, 611–615.PubMedCrossRefGoogle Scholar
  11. 11.
    Kosinski, J., Mosalaganti, S., von Appen, A., Teimer, R., DiGuilio, A. L., et al. (2016). Molecular architecture of the inner ring scaffold of the human nuclear pore complex. Science, 352, 363–365.PubMedCrossRefGoogle Scholar
  12. 12.
    Kim, S. J., Fernandez-Martinez, J., Nudelman, I., Shi, Y., Zhang, W., et al. (2018). Integrative structure and functional anatomy of a nuclear pore complex. Nature, 555, 475–482.PubMedPubMedCentralCrossRefGoogle Scholar
  13. 13.
    Forbes, D. J., Kirschner, M. W., & Newport, J. W. (1983). Spontaneous formation of nucleus-like structures around bacteriophage DNA microinjected into Xenopus eggs. Cell, 34(1), 13–23.PubMedCrossRefGoogle Scholar
  14. 14.
    Lohka, M. J., & Masui, Y. (1984). Roles of cytosol and cytoplasmic particles in nuclear envelope assembly and sperm pronuclear formation in cell-free preparations from amphibian eggs. The Journal of Cell Biology, 98(4), 1222–1230.PubMedCrossRefGoogle Scholar
  15. 15.
    Newmeyer, D. D., Finlay, D. R., & Forbes, D. J. (1986). In vitro transport of a fluorescent nuclear protein and exclusion of non-nuclear proteins. The Journal of Cell Biology, 103(6 Pt. 1), 2091–2102.PubMedCrossRefGoogle Scholar
  16. 16.
    Newport, J. (1987). Nuclear reconstitution in vitro: Stages of assembly around protein-free DNA. Cell, 48(2), 205–217.PubMedCrossRefGoogle Scholar
  17. 17.
    Newport, J., & Dunphy, W. (1992). Characterization of the membrane binding and fusion events during nuclear envelope assembly using purified components. The Journal of Cell Biology, 116(2), 295–306.PubMedCrossRefGoogle Scholar
  18. 18.
    Kohler, A., & Hurt, E. (2010). Gene regulation by nucleoporins and links to cancer. Molecular Cell, 3, 6–15.CrossRefGoogle Scholar
  19. 19.
    Nousiainen, H. O., Kestila, M., Pakkasjarvi, N., Honkala, H., Kuure, S., Tallila, J., Vuopala, K., Ignatius, J., Herva, R., & Peltonen, L. (2008). Mutations in mRNA export mediator GLE1 result in a fetal motoneuron disease. Nature Genetics, 40, 155–157.PubMedPubMedCentralCrossRefGoogle Scholar
  20. 20.
    Savas, J. N., Toyama, B. H., Xu, T., Yates, J. R., 3rd., & Hetzer, M. W. (2012). Extremely long-lived nuclear pore proteins in the rat brain. Science, 335, 942.PubMedPubMedCentralCrossRefGoogle Scholar
  21. 21.
    Boehmer, T., Jeudy, S., Berke, I. C., & Schwartz, T. U. (2008). Structural and functional studies of Nup107/Nup133 interaction and its implications for the architecture of the nuclear pore complex. Molecular Cell, 30, 721–731.PubMedPubMedCentralCrossRefGoogle Scholar
  22. 22.
    Brohawn, S. G., Leksa, N. C., Spear, E. D., Rajashankar, K. R., & Schwartz, T. U. (2008). Structural evidence for common ancestry of the nuclear pore complex and vesicle coats. Science, 322, 1369–1373.PubMedPubMedCentralCrossRefGoogle Scholar
  23. 23.
    Debler, E. W., Ma, Y., Seo, H. S., Hsia, K. C., Noriega, T. R., Blobel, G., & Hoelz, A. (2008). A fence-like coat for the nuclear pore membrane. Molecular Cell, 32, 815–826.PubMedCrossRefGoogle Scholar
  24. 24.
    Brohawn, S. G., & Schwartz, T. U. (2009). Molecular architecture of the Nup84–Nup145C–Sec13 edge element in the nuclear pore complex lattice. Nature Structural & Molecular Biology, 16, 1173–1177.CrossRefGoogle Scholar
  25. 25.
    Cohen, S., Au, S., & Panté, N. (2011). How viruses access the nucleus. Biochimica et Biophysica Acta (BBA)-Molecular Cell Research, 1813, 1634–1645.CrossRefGoogle Scholar
  26. 26.
    Le Sage, V., & Mouland, A. J. (2013). Viral subversion of the nuclear pore complex. Viruses, 5, 2019–2042.PubMedPubMedCentralCrossRefGoogle Scholar
  27. 27.
    Yarbrough, M. L., Mata, M. A., Sakthivel, R., & Fontoura, B. M. (2014). Viral subversion of nucleocytoplasmic trafficking. Traffic, 15, 127–140.PubMedCrossRefGoogle Scholar
  28. 28.
    Lin, D. H., Zimmermann, S., Stuwe, T., Stuwe, E., & Hoelz, A. (2013). Structural and functional analysis of the C-terminal domain of Nup358/RanBP2. Journal of Molecular Biology, 425, 1318–1329.PubMedPubMedCentralCrossRefGoogle Scholar
  29. 29.
    Schaller, T., Ocwieja, K. E., Rasaiyaah, J., Price, A. J., Brady, T. L., et al. (2011). HIV-1 capsid-cyclophilin interactions determine nuclear import pathway, integration targeting and replication efficiency. PLoS Pathogens, 7, e1002439.PubMedPubMedCentralCrossRefGoogle Scholar
  30. 30.
    Bichel, K., Price, A. J., Schaller, T., Towers, G. J., Freund, S. M., & James, L. C. (2013). HIV-1 capsid undergoes coupled binding and isomerization by the nuclear pore protein NUP358. Retrovirology, 10, 81.PubMedPubMedCentralCrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Department of PhysiologyWayne State University School of MedicineDetroitUSA

Personalised recommendations