1. Physics of Living Systems
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A physical model describing the interaction of nuclear transport receptors with FG nucleoporin domain assemblies

  1. Raphael Zahn
  2. Dino Osmanović
  3. Severin Ehret
  4. Carolina Araya Callis
  5. Steffen Frey
  6. Murray Stewart
  7. Changjiang You
  8. Dirk Görlich
  9. Bart W Hoogenboom
  10. Ralf P Richter  Is a corresponding author
  1. CIC biomaGUNE, Spain
  2. University College London, United Kingdom
  3. NanoTag Biotechnologies, Germany
  4. Medical Research Council Laboratory of Molecular Biology, United Kingdom
  5. University of Osnabrück, Germany
  6. Max Planck Institute for Biophysical Chemistry, Germany
Research Article
  • Cited 36
  • Views 2,472
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Cite this article as: eLife 2016;5:e14119 doi: 10.7554/eLife.14119

Abstract

The permeability barrier of nuclear pore complexes (NPCs) controls bulk nucleocytoplasmic exchange. It consists of nucleoporin domains rich in phenylalanine-glycine motifs (FG domains). As a bottom-up nanoscale model for the permeability barrier, we have used planar films produced with three different end-grafted FG domains and quantitatively analyzed the binding of two different nuclear transport receptors (NTRs), NTF2 and Importin β, together with the concomitant film thickness changes. NTR binding caused only moderate changes in film thickness; the binding isotherms showed negative cooperativity and could all be mapped onto a single master curve. This universal NTR binding behavior - a key element for the transport selectivity of the NPC - was quantitatively reproduced by a physical model that treats FG domains as regular, flexible polymers, and NTRs as spherical colloids with a homogeneous surface, ignoring the detailed arrangement of interaction sites along FG domains and on the NTR surface.

Article and author information

Author details

  1. Raphael Zahn

    Biosurfaces Lab, CIC biomaGUNE, San Sebastian, Spain
    Competing interests
    The authors declare that no competing interests exist.
  2. Dino Osmanović

    London Centre for Nanotechnology, Department of Physics and Astronomy, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Severin Ehret

    Biosurfaces Lab, CIC biomaGUNE, San Sebastian, Spain
    Competing interests
    The authors declare that no competing interests exist.
  4. Carolina Araya Callis

    Biosurfaces Lab, CIC biomaGUNE, San Sebastian, Spain
    Competing interests
    The authors declare that no competing interests exist.
  5. Steffen Frey

    NanoTag Biotechnologies, Göttingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Murray Stewart

    Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Changjiang You

    Department of Biology, University of Osnabrück, Osnabrück, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Dirk Görlich

    Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  9. Bart W Hoogenboom

    London Centre for Nanotechnology, Department of Physics and Astronomy, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  10. Ralf P Richter

    Biosurfaces Lab, CIC biomaGUNE, San Sebastian, Spain
    For correspondence
    rrichter@cicbiomagune.es
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany

Publication history

  1. Received: January 4, 2016
  2. Accepted: April 7, 2016
  3. Accepted Manuscript published: April 8, 2016 (version 1)
  4. Version of Record published: May 20, 2016 (version 2)

Copyright

© 2016, Zahn et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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