1. Biochemistry and Chemical Biology
  2. Cell Biology
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A mitotic kinase scaffold depleted in testicular seminomas impacts spindle orientation in germline stem cells

  1. Heidi Hehnly
  2. David Canton
  3. Paula Bucko
  4. Lorene K Langeberg
  5. Leah Ogier
  6. Irwin Gelman
  7. L Fernando Santana
  8. Linda Wordeman
  9. John D Scott  Is a corresponding author
  1. Howard Hughes Medical Institute, University of Washington, United States
  2. Roswell Park Cancer Institute, United States
  3. University of Washington, United States
Research Article
  • Cited 35
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Cite this article as: eLife 2015;4:e09384 doi: 10.7554/eLife.09384

Abstract

Correct orientation of the mitotic spindle in stem cells underlies organogenesis. Spindle abnormalities correlate with cancer progression in germline-derived tumors. We discover a macromolecular complex between the scaffolding protein Gravin/AKAP12 and the mitotic kinases, Aurora A and Plk1 that is down regulated in human seminoma. Depletion of Gravin correlates with an increased mitotic index and disorganization of seminiferous tubules. Biochemical, super-resolution imaging and enzymology approaches establish that this Gravin scaffold accumulates at the mother spindle pole during metaphase. Manipulating elements of the Gravin-Aurora A-Plk1 axis prompts mitotic delay and prevents appropriate assembly of astral microtubules to promote spindle misorientation. These pathological responses are conserved in seminiferous tubules from Gravin-/- mice where an overabundance of Oct3/4 positive germline stem cells display randomized orientation of mitotic spindles. Thus we propose that Gravin-mediated recruitment of Aurora A and Plk1 to the mother (oldest) spindle pole contributes to the fidelity of symmetric cell division.

Article and author information

Author details

  1. Heidi Hehnly

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. David Canton

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Paula Bucko

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Lorene K Langeberg

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Leah Ogier

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Irwin Gelman

    Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. L Fernando Santana

    Department of Physiology and Biophysics, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Linda Wordeman

    Department of Physiology and Biophysics, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. John D Scott

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    For correspondence
    scottjdw@u.washington.edu
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#4196-01) of the University of Washington.

Reviewing Editor

  1. Roger Davis, Howard Hughes Medical Institute & University of Massachusetts Medical School, United States

Publication history

  1. Received: June 12, 2015
  2. Accepted: September 20, 2015
  3. Accepted Manuscript published: September 25, 2015 (version 1)
  4. Version of Record published: October 23, 2015 (version 2)

Copyright

© 2015, Hehnly 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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Further reading

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