CaMKII autophosphorylation can occur between holoenzymes without subunit exchange

  1. Iva Lučić  Is a corresponding author
  2. Léonie Héluin
  3. Pin-Lian Jiang
  4. Alejandro G Castro Scalise
  5. Cong Wang
  6. Andreas Franz
  7. Florian Heyd
  8. Markus Wahl
  9. Fan Liu
  10. Andrew J R Plested  Is a corresponding author
  1. Humboldt-Universität zu Berlin, Germany
  2. Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Germany
  3. Freie Universität Berlin, Germany

Abstract

The dodecameric protein kinase CaMKII is expressed throughout the body. The alpha isoform is responsible for synaptic plasticity and participates in memory through its phosphorylation of synaptic proteins. Its elaborate subunit organization and propensity for autophosphorylation allow it to preserve neuronal plasticity across space and time. The prevailing hypothesis for the spread of CaMKII activity, involving shuffling of subunits between activated and naïve holoenzymes, is broadly termed subunit exchange. In contrast to the expectations of previous work, we found little evidence for subunit exchange upon activation, and no effect of restraining subunits to their parent holoenzymes. Rather, mass photometry, crosslinking mass spectrometry, single molecule TIRF microscopy and biochemical assays identify inter-holoenzyme phosphorylation (IHP) as the mechanism for spreading phosphorylation. The transient, activity-dependent formation of groups of holoenzymes is well suited to the speed of neuronal activity. Our results place fundamental limits on the activation mechanism of this kinase.

Data availability

All data generated during this study are included in the manuscript, supporting figures and supporting tables.

Article and author information

Author details

  1. Iva Lučić

    Institute of Biology, Cellular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
    For correspondence
    iva.lucic@hu-berlin.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8077-2195
  2. Léonie Héluin

    Institute of Biology, Cellular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Pin-Lian Jiang

    Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Alejandro G Castro Scalise

    Institute of Biology, Cellular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Cong Wang

    Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Andreas Franz

    Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Florian Heyd

    Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9377-9882
  8. Markus Wahl

    Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2811-5307
  9. Fan Liu

    Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  10. Andrew J R Plested

    Institute of Biology, Cellular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
    For correspondence
    andrew.plested@hu-berlin.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6062-0832

Funding

HORIZON EUROPE Marie Sklodowska-Curie Actions (798696)

  • Iva Lučić

Deutsche Forschungsgemeinschaft (272140445)

  • Andrew J R Plested

Deutsche Forschungsgemeinschaft (323514590 & 446182550)

  • Andrew J R Plested

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

Reviewing Editor

  1. Takeo Saneyoshi, Kyoto University, Japan

Version history

  1. Preprint posted: August 5, 2022 (view preprint)
  2. Received: January 10, 2023
  3. Accepted: August 10, 2023
  4. Accepted Manuscript published: August 11, 2023 (version 1)
  5. Version of Record published: August 30, 2023 (version 2)
  6. Version of Record updated: August 31, 2023 (version 3)

Copyright

© 2023, Lučić 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. Iva Lučić
  2. Léonie Héluin
  3. Pin-Lian Jiang
  4. Alejandro G Castro Scalise
  5. Cong Wang
  6. Andreas Franz
  7. Florian Heyd
  8. Markus Wahl
  9. Fan Liu
  10. Andrew J R Plested
(2023)
CaMKII autophosphorylation can occur between holoenzymes without subunit exchange
eLife 12:e86090.
https://doi.org/10.7554/eLife.86090

Share this article

https://doi.org/10.7554/eLife.86090

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