Cardiac ryanodine receptor distribution is dynamic and changed by auxiliary proteins and post-translational modification

Abstract

The effects of the immunophilins, FKBP12 and FKBP12.6, and phosphorylation on type II ryanodine receptor (RyR2) arrangement and function were examined using correlation microscopy (line scan confocal imaging of Ca2+ sparks and dual-tilt electron tomography) and dSTORM imaging of permeabilized Wistar rat ventricular myocytes. Saturating concentrations (10 µmol/L) of either FKBP12 or 12.6 significantly reduced the frequency, spread, amplitude and Ca2+ spark mass relative to control, while the tomograms revealed both proteins shifted the tetramers into a largely side-by-side configuration. Phosphorylation of immunophilin-saturated RyR2 resulted in structural and functional changes largely comparable to phosphorylation alone. dSTORM images of myocyte surfaces demonstrated that both FKBP12 and 12.6 significantly reduced RyR2 cluster sizes, while phosphorylation, even of immunophilin-saturated RyR2, increased them. We conclude that both RyR2 cluster size and the arrangement of tetramers within clusters is dynamic and respond to changes in the cellular environment. Further, these changes affect Ca2+ spark formation.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided where required.

Article and author information

Author details

  1. Parisa Asghari

    Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2285-3242
  2. David RL Scriven

    Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Myles Ng

    Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Pankaj Panwar

    Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  5. Keng C Chou

    Department of Chemistry, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  6. Filip van Petegem

    Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  7. Edwin DW Moore

    Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
    For correspondence
    edwin.moore@ubc.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7519-5592

Funding

Canadian Institutes of Health Research (148527)

  • Edwin DW Moore

Canadian Institutes of Health Research (PJT-153305)

  • Filip van Petegem

Natural Sciences and Engineering Research Council of Canada

  • Keng C Chou

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

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations provided by the Canadian Council on Animal Care. All of the animals were handled according to a protocol (A17-0040) approved by the Animal Care Committee of the University of British Columbia.

Copyright

© 2020, Asghari 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. Parisa Asghari
  2. David RL Scriven
  3. Myles Ng
  4. Pankaj Panwar
  5. Keng C Chou
  6. Filip van Petegem
  7. Edwin DW Moore
(2020)
Cardiac ryanodine receptor distribution is dynamic and changed by auxiliary proteins and post-translational modification
eLife 9:e51602.
https://doi.org/10.7554/eLife.51602

Share this article

https://doi.org/10.7554/eLife.51602

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