1. Cell Biology

The microtubule polymerase Stu2 promotes oligomerization of the γ-TuSC for cytoplasmic microtubule nucleation

  1. Judith Gunzelmann
  2. Diana Rüthnick
  3. Tien-chen Lin
  4. Wanlu Zhang
  5. Annett Neuner
  6. Ursula Jäkle
  7. Elmar Schiebel  Is a corresponding author
  1. Universität Heidelberg, Germany
https://doi.org/10.7554/eLife.39932
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Cite this article
  1. Judith Gunzelmann
  2. Diana Rüthnick
  3. Tien-chen Lin
  4. Wanlu Zhang
  5. Annett Neuner
  6. Ursula Jäkle
  7. Elmar Schiebel
(2018)
The microtubule polymerase Stu2 promotes oligomerization of the γ-TuSC for cytoplasmic microtubule nucleation
eLife 7:e39932.
https://doi.org/10.7554/eLife.39932
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Abstract

Stu2/XMAP215/ZYG-9/Dis1/Alp14/Msps/ch-TOG family members nucleate microtubules together with γ-tubulin complexes. However, we know little about the interplay of these nucleation factors. Here, we show that the budding yeast Stu2 in complex with the γ-tubulin receptor Spc72 nucleates microtubules in vitro without the small γ-tubulin complex (γ-TuSC). Upon γ-TuSC addition, Stu2 facilitates Spc72-γ-TuSC interaction by binding to Spc72 and γ-TuSC. Stu2 together with Spc72-γ-TuSC increases microtubule nucleation depended on the TOG domains of Stu2. Importantly, these activities are also important for microtubule nucleation in vivo. Stu2 stabilizes Spc72-γ-TuSC at the minus end of cytoplasmic microtubules (cMTs) and an in vivo assay indicates that cMT nucleation requires the TOG domains of Stu2. Upon γ-tubulin depletion, we observed efficient cMT nucleation away from the SPB, which was dependent on Stu2. Thus, γ-TuSC restricts cMT assembly to the SPB while Stu2 nucleates cMTs together with γ-TuSC and stabilizes γ-TuSC at the cMT minus end.

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All data generated or analysed during this study are included in the manuscript and supporting files.

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Author details

  1. Judith Gunzelmann

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.

  2. Diana Rüthnick

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6365-4050

  3. Tien-chen Lin

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.

  4. Wanlu Zhang

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.

  5. Annett Neuner

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.

  6. Ursula Jäkle

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.

  7. Elmar Schiebel

    Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
    For correspondence
    e.schiebel@zmbh.uni-heidelberg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3683-247X

Funding

Deutsche Forschungsgemeinschaft (Schi295/4-3)

  • Judith Gunzelmann
  • Tien-chen Lin
  • Annett Neuner
  • Ursula Jäkle

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

Reviewing Editor

  1. Anna Akhmanova, Utrecht University, Netherlands

Version history

  1. Received: July 10, 2018
  2. Accepted: September 14, 2018
  3. Accepted Manuscript published: September 17, 2018 (version 1)
  4. Version of Record published: September 26, 2018 (version 2)

Copyright

© 2018, Gunzelmann 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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  1. Judith Gunzelmann
  2. Diana Rüthnick
  3. Tien-chen Lin
  4. Wanlu Zhang
  5. Annett Neuner
  6. Ursula Jäkle
  7. Elmar Schiebel
(2018)
The microtubule polymerase Stu2 promotes oligomerization of the γ-TuSC for cytoplasmic microtubule nucleation
eLife 7:e39932.
https://doi.org/10.7554/eLife.39932

Share this article

https://doi.org/10.7554/eLife.39932

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