1. Cell Biology
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A FRET-based study reveals site-specific regulation of spindle position checkpoint proteins at yeast centrosomes

  1. Yuliya Gryaznova
  2. Ayse Koca Caydasi
  3. Gabriele Malengo
  4. Victor Sourjik
  5. Gislene Pereira  Is a corresponding author
  1. German Cancer Research Centre, Germany
  2. Centre for Molecular Biology, Germany
Research Article
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Cite this article as: eLife 2016;5:e14029 doi: 10.7554/eLife.14029

Abstract

The spindle position checkpoint (SPOC) is a spindle pole body (SPB, equivalent of mammalian centrosome) associated surveillance mechanism that halts mitotic exit upon spindle mis-orientation. Here, we monitored the interaction between SPB proteins and the SPOC component Bfa1 by FRET microscopy. We show that Bfa1 binds to the scaffold-protein Nud1 and the γ-tubulin receptor Spc72. Spindle misalignment specifically disrupts Bfa1-Spc72 interaction by a mechanism that requires the 14-3-3-family protein Bmh1 and the MARK/PAR-kinase Kin4. Dissociation of Bfa1 from Spc72 prevents the inhibitory phosphorylation of Bfa1 by the polo-like kinase Cdc5. We propose Spc72 as a regulatory hub that coordinates the activity of Kin4 and Cdc5 towards Bfa1. In addition, analysis of spc72∆ cells shows that a mitotic-exit-promoting dominant signal, which is triggered upon elongation of the spindle into the bud, overrides the SPOC. Our data reinforce the importance of daughter-cell-associated factors and centrosome-based regulations in mitotic exit and SPOC control.

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Author details

  1. Yuliya Gryaznova

    DKFZ-ZMBH Alliance, German Cancer Research Centre, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Ayse Koca Caydasi

    DKFZ-ZMBH Alliance, German Cancer Research Centre, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Gabriele Malengo

    DKFZ-ZMBH Alliance, Centre for Molecular Biology, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Victor Sourjik

    DKFZ-ZMBH Alliance, Centre for Molecular Biology, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Gislene Pereira

    DKFZ-ZMBH Alliance, German Cancer Research Centre, Heidelberg, Germany
    For correspondence
    gislene.pereira@cos.uni-heidelberg.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Yukiko M Yamashita, University of Michigan, United States

Publication history

  1. Received: December 23, 2015
  2. Accepted: May 8, 2016
  3. Accepted Manuscript published: May 9, 2016 (version 1)
  4. Accepted Manuscript updated: May 20, 2016 (version 2)
  5. Version of Record published: May 24, 2016 (version 3)
  6. Version of Record updated: June 3, 2016 (version 4)

Copyright

© 2016, Gryaznova 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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