1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics
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Flexible linkers in CaMKII control the balance between activating and inhibitory autophosphorylation

  1. Moitrayee Bhattacharyya
  2. Young Kwang Lee
  3. Serena Muratcioglu
  4. Baiyu Qiu
  5. Priya Nyayapati
  6. Howard Schulman
  7. Jay T Groves  Is a corresponding author
  8. John Kuriyan  Is a corresponding author
  1. University of California, Berkeley, United States
  2. San Diego State University, United States
  3. Panorama Institute of Molecular Medicine, United States
Research Article
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Cite this article as: eLife 2020;9:e53670 doi: 10.7554/eLife.53670

Abstract

The many variants of human Ca2+/calmodulin-dependent protein kinase II (CaMKII) differ in the lengths and sequences of disordered linkers connecting the kinase domains to the oligomeric hub of the holoenzyme. CaMKII activity depends on the balance between activating and inhibitory autophosphorylation (on Thr 286 and Thr 305/306, respectively, in the human a isoform). Variation in the linkers could alter transphosphorylation rates within a holoenzyme and the balance of autophosphorylation outcomes. We show, using mammalian-cell expression and a single-molecule assay, that the balance of autophosphorylation is flipped between CaMKII variants with longer and shorter linkers. For the principal isoforms in the brain, CaMKII-a, with a ~30 residue linker, readily acquires activating autophosphorylation, while CaMKII-b, with a ~200 residue linker, is biased towards inhibitory autophosphorylation. Our results show how the responsiveness of CaMKII holoenzymes to calcium signals can be tuned by varying the relative levels of isoforms with long and short linkers.

Article and author information

Author details

  1. Moitrayee Bhattacharyya

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2168-1541
  2. Young Kwang Lee

    Department of Molecular and Cell Biology, San Diego State University, San Diego, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0056-6357
  3. Serena Muratcioglu

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  4. Baiyu Qiu

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  5. Priya Nyayapati

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  6. Howard Schulman

    Panorama Institute of Molecular Medicine, Sunnyvale, United States
    Competing interests
    No competing interests declared.
  7. Jay T Groves

    QB3, University of California, Berkeley, Berkeley, United States
    For correspondence
    JTGroves@lbl.gov
    Competing interests
    No competing interests declared.
  8. John Kuriyan

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    jkuriyan@mac.com
    Competing interests
    John Kuriyan, Senior editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4414-5477

Funding

National Institute of General Medical Sciences (K99 GM 126145)

  • Moitrayee Bhattacharyya

Howard Hughes Medical Institute

  • John Kuriyan

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

Reviewing Editor

  1. Tony Hunter, Salk Institute for Biological Studies, United States

Publication history

  1. Received: November 15, 2019
  2. Accepted: March 6, 2020
  3. Accepted Manuscript published: March 9, 2020 (version 1)
  4. Version of Record published: April 8, 2020 (version 2)

Copyright

© 2020, Bhattacharyya 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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