1. Cell Biology
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Exportin Crm1 is repurposed as a docking protein to generate microtubule organizing centers at the nuclear pore

  1. Xun X Bao
  2. Christos Spanos
  3. Tomoko Kojidani
  4. Eric M Lynch
  5. Juri Rappsilber
  6. Yasushi Hiraoka
  7. Tokuko Haraguchi
  8. Kenneth E Sawin  Is a corresponding author
  1. University of Edinburgh, United Kingdom
  2. National Institute of Information and Communications Technology, Japan
Research Article
  • Cited 9
  • Views 1,965
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Cite this article as: eLife 2018;7:e33465 doi: 10.7554/eLife.33465

Abstract

Non-centrosomal microtubule organizing centers (MTOCs) are important for microtubule organization in many cell types. In fission yeast Schizosaccharomyces pombe, the protein Mto1, together with partner protein Mto2 (Mto1/2 complex), recruits the g-tubulin complex to multiple non-centrosomal MTOCs, including the nuclear envelope (NE). Here, we develop a comparative-interactome mass spectrometry approach to determine how Mto1 localizes to the NE. Surprisingly, we find that Mto1, a constitutively cytoplasmic protein, docks at nuclear pore complexes (NPCs), via interaction with exportin Crm1 and cytoplasmic FG-nucleoporin Nup146. Although Mto1 is not a nuclear export cargo, it binds Crm1 via a nuclear export signal-like sequence, and docking requires both Ran in the GTP-bound state and Nup146 FG repeats. In addition to determining the mechanism of MTOC formation at the NE, our results reveal a novel role for Crm1 and the nuclear export machinery in the stable docking of a cytoplasmic protein complex at NPCs.

Data availability

The mass spectrometry proteomics data from both LFQ and SILAC experiments have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD008334

The following data sets were generated

Article and author information

Author details

  1. Xun X Bao

    Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4733-3550
  2. Christos Spanos

    Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4376-8242
  3. Tomoko Kojidani

    Advanced ICT Research Institute, National Institute of Information and Communications Technology, Kobe, Japan
    Competing interests
    The authors declare that no competing interests exist.
  4. Eric M Lynch

    Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5897-5167
  5. Juri Rappsilber

    Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5999-1310
  6. Yasushi Hiraoka

    Advanced ICT Research Institute, National Institute of Information and Communications Technology, Kobe, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9407-8228
  7. Tokuko Haraguchi

    Advanced ICT Research Institute, National Institute of Information and Communications Technology, Kobe, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3813-6785
  8. Kenneth E Sawin

    Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
    For correspondence
    ken.sawin@ed.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2607-2219

Funding

Wellcome (94517)

  • Xun X Bao
  • Eric M Lynch
  • Kenneth E Sawin

Japan Society for the Promotion of Science (JP25116006)

  • Tomoko Kojidani
  • Tokuko Haraguchi

The Darwin Trust of Edinburgh

  • Xun X Bao

Wellcome (108504)

  • Christos Spanos
  • Juri Rappsilber

Wellcome (91020)

  • Christos Spanos
  • Juri Rappsilber

Wellcome (203149)

  • Xun X Bao
  • Christos Spanos
  • Eric M Lynch
  • Juri Rappsilber
  • Kenneth E Sawin

Japan Society for the Promotion of Science (JP17H03636)

  • Tomoko Kojidani
  • Tokuko Haraguchi

Japan Society for the Promotion of Science (JP17H01444)

  • Yasushi Hiraoka

Japan Society for the Promotion of Science (JP16H01309)

  • Yasushi Hiraoka

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Karsten Weis, ETH Zurich, Switzerland

Publication history

  1. Received: November 9, 2017
  2. Accepted: May 21, 2018
  3. Accepted Manuscript published: May 29, 2018 (version 1)
  4. Version of Record published: June 19, 2018 (version 2)

Copyright

© 2018, Bao 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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