A dynamic mechanism for allosteric activation of Aurora kinase A by activation loop phosphorylation

  1. Emily F Ruff
  2. Joseph M Muretta
  3. Andrew R Thompson
  4. Eric W Lake
  5. Soreen Cyphers
  6. Steven K Albanese
  7. Sonya M Hanson
  8. Julie M Behr
  9. David D Thomas
  10. John D Chodera
  11. Nicholas M Levinson  Is a corresponding author
  1. University of Minnesota, United States
  2. Memorial Sloan Kettering Cancer Center, United States

Abstract

Many eukaryotic protein kinases are activated by phosphorylation on a specific conserved residue in the regulatory activation loop, a post-translational modification thought to stabilize the active DFG-In state of the catalytic domain. Here we use a battery of spectroscopic methods that track different catalytic elements of the kinase domain to show that the ~100-fold activation of the mitotic kinase Aurora A (AurA) by phosphorylation occurs without a population shift from the DFG-Out to the DFG-In state, and that the activation loop of the activated kinase remains highly dynamic. Instead, molecular dynamics simulations and electron paramagnetic resonance experiments show that phosphorylation triggers a switch within the DFG-In subpopulation from an autoinhibited DFG-In substate to an active DFG-In substate, leading to catalytic activation. This mechanism raises new questions about the functional role of the DFG-Out state in protein kinases.

Article and author information

Author details

  1. Emily F Ruff

    Department of Pharmacology, University of Minnesota, Minneapolis, United States
    Competing interests
    No competing interests declared.
  2. Joseph M Muretta

    Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, United States
    Competing interests
    No competing interests declared.
  3. Andrew R Thompson

    Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, United States
    Competing interests
    No competing interests declared.
  4. Eric W Lake

    Department of Pharmacology, University of Minnesota, Minneapolis, United States
    Competing interests
    No competing interests declared.
  5. Soreen Cyphers

    Department of Pharmacology, University of Minnesota, Minneapolis, United States
    Competing interests
    No competing interests declared.
  6. Steven K Albanese

    Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0973-5030
  7. Sonya M Hanson

    Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8960-5353
  8. Julie M Behr

    Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
  9. David D Thomas

    Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, United States
    Competing interests
    No competing interests declared.
  10. John D Chodera

    Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    John D Chodera, is a member of the Scientific Advisory Board for Schrödinger, LLC.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0542-119X
  11. Nicholas M Levinson

    Department of Pharmacology, University of Minnesota, Minneapolis, United States
    For correspondence
    nml@umn.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4338-8087

Funding

National Institutes of Health (R00 Award GM102288)

  • Nicholas M Levinson

National Institutes of Health (R21 Award CA217695)

  • Nicholas M Levinson

National Institutes of Health (NRSA Award F32GM120817)

  • Emily F Ruff

National Institutes of Health (P30-CA008748)

  • John D Chodera

National Institutes of Health (GM121505)

  • John D Chodera

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

Reviewing Editor

  1. William I Weis, Stanford University Medical Center, United States

Publication history

  1. Received: October 13, 2017
  2. Accepted: February 19, 2018
  3. Accepted Manuscript published: February 21, 2018 (version 1)
  4. Version of Record published: March 13, 2018 (version 2)

Copyright

© 2018, Ruff 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. Emily F Ruff
  2. Joseph M Muretta
  3. Andrew R Thompson
  4. Eric W Lake
  5. Soreen Cyphers
  6. Steven K Albanese
  7. Sonya M Hanson
  8. Julie M Behr
  9. David D Thomas
  10. John D Chodera
  11. Nicholas M Levinson
(2018)
A dynamic mechanism for allosteric activation of Aurora kinase A by activation loop phosphorylation
eLife 7:e32766.
https://doi.org/10.7554/eLife.32766
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