1. Cell Biology
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Spatial signals link exit from mitosis to spindle position

  1. Jill E Falk
  2. Dai Tsuchiya
  3. Jolien Verdaasdonk
  4. Soni Lacefield
  5. Kerry Bloom
  6. Angelika Amon  Is a corresponding author
  1. Howard Hughes Medical Institute, Massachusetts Institute of Technology, United States
  2. Indiana University, United States
  3. The University of North Carolina at Chapel Hill, United States
Research Article
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Cite this article as: eLife 2016;5:e14036 doi: 10.7554/eLife.14036

Abstract

In budding yeast, if the spindle becomes mispositioned, cells prevent exit from mitosis by inhibiting the mitotic exit network (MEN). The MEN is a signaling cascade that localizes to spindle pole bodies (SPBs) and activates the phosphatase Cdc14. There are two competing models that explain MEN regulation by spindle position. In the "zone model", exit from mitosis occurs when a MEN-bearing SPB enters the bud. The "cMT-bud neck model" posits that cytoplasmic microtubule (cMT)-bud neck interactions prevent MEN activity. Here we find that 1) eliminating cMT- bud neck interactions does not trigger exit from mitosis and 2) loss of these interactions does not precede Cdc14 activation. Furthermore, using binucelate cells, we show that exit from mitosis occurs when one SPB enters the bud despite the presence of a mispositioned spindle. We conclude that exit from mitosis is triggered by a correctly positioned spindle rather than inhibited by improper spindle position.

Article and author information

Author details

  1. Jill E Falk

    David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Dai Tsuchiya

    Department of Biology, Indiana University, Bloomington, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jolien Verdaasdonk

    Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Soni Lacefield

    Department of Biology, Indiana University, Bloomington, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Kerry Bloom

    Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Angelika Amon

    David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, United States
    For correspondence
    angelika@mit.edu
    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 24, 2015
  2. Accepted: April 7, 2016
  3. Accepted Manuscript published: May 11, 2016 (version 1)
  4. Version of Record published: May 31, 2016 (version 2)

Copyright

© 2016, Falk 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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