Intrinsic disorder within AKAP79 fine-tunes anchored phosphatase activity toward substrates and drug sensitivity

  1. Patrick J Nygren
  2. Sohum Mehta
  3. Devin K Schweppe
  4. Lorene K Langeberg
  5. Jennifer L Whiting
  6. Chad R Weisbrod
  7. James E. Bruce
  8. Jin Zhang
  9. David Veesler
  10. John D Scott  Is a corresponding author
  1. Howard Hughes Medical Institute, University of Washington, United States
  2. University of California, San Diego, United States
  3. University of Washington, United States
  4. Florida State University, United States

Abstract

Scaffolding the calcium/calmodulin-dependent phosphatase 2B (PP2B, calcineurin) focuses and insulates termination of local second messenger responses. Conformational flexibility in regions of intrinsic disorder within A-kinase anchoring protein 79 (AKAP79) delineates PP2B access to phosphoproteins. Structural analysis by negative-stain electron microscopy (EM) reveals an ensemble of dormant AKAP79-PP2B configurations varying in particle length from 160-240 Å. A short-linear interaction motif between residues 337-343 of AKAP79 is the sole PP2B-anchoring determinant sustaining these diverse topologies. Activation with Ca2+/calmodulin engages additional interactive surfaces and condenses these conformational variants into a uniform population with mean length 178 ± 17 Å. This includes a Leu-Lys-Ile-Pro sequence (residues 125-128 of AKAP79) that occupies a binding pocket on PP2B utilized by the immunosuppressive drug cyclosporin. Live-cell imaging with fluorescent activity-sensors infers that this region fine-tunes calcium responsiveness and drug sensitivity of the anchored phosphatase.

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Author details

  1. Patrick J Nygren

    Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8688-9389
  2. Sohum Mehta

    Department of Pharmacology, University of California, San Diego, San Diego, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Devin K Schweppe

    Department of Genome Sciences, 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. Jennifer L Whiting

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

    National High Magnetic Field Laboratory, Florida State University, Tallahassee, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. James E. Bruce

    Department of Genome Sciences, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Jin Zhang

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7145-7823
  9. David Veesler

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. 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.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0367-8146

Funding

Howard Hughes Medical Institute

  • John D Scott

National Institutes of Health (1R01GM120553)

  • David Veesler

National Institutes of Health (5R01DK105542)

  • John D Scott

National Institutes of Health (4P01DK054441)

  • John D Scott

National Institutes of Health (R01DK073368)

  • Jin Zhang

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

Reviewing Editor

  1. Roger J Davis, University of Massachusetts Medical School, United States

Publication history

  1. Received: July 29, 2017
  2. Accepted: September 28, 2017
  3. Accepted Manuscript published: October 2, 2017 (version 1)
  4. Version of Record published: October 23, 2017 (version 2)

Copyright

© 2017, Nygren 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. Patrick J Nygren
  2. Sohum Mehta
  3. Devin K Schweppe
  4. Lorene K Langeberg
  5. Jennifer L Whiting
  6. Chad R Weisbrod
  7. James E. Bruce
  8. Jin Zhang
  9. David Veesler
  10. John D Scott
(2017)
Intrinsic disorder within AKAP79 fine-tunes anchored phosphatase activity toward substrates and drug sensitivity
eLife 6:e30872.
https://doi.org/10.7554/eLife.30872

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