PACT-mediated PKR activation acts as a hyperosmotic stress intensity sensor weakening osmoadaptation and enhancing inflammation

  1. Kenneth T Farabaugh
  2. Dawid Krokowski
  3. Bo-Jhih Guan
  4. Zhaofeng Gao
  5. Xing-Huang Gao
  6. Jing Wu
  7. Raul Jobava
  8. Greeshma Ray
  9. Tristan J de Jesus
  10. Massimiliano G Bianchi
  11. Evelyn Chukwurah
  12. Ovidio Bussolati
  13. Michael Kilberg
  14. David A Buchner
  15. Ganes C Sen
  16. Calvin Cotton
  17. Christine McDonald
  18. Michelle Longworth
  19. Parameswaran Ramakrishnan  Is a corresponding author
  20. Maria Hatzoglou  Is a corresponding author
  1. Case Western Reserve University, United States
  2. Cleveland Clinic Foundation, United States
  3. Universita degli Studi di Parma, Italy
  4. University of Parma, Italy
  5. University of Florida, United States

Abstract

The inability of cells to adapt to increased environmental tonicity can lead to inflammatory gene expression and pathogenesis. The Rel family of transcription factors TonEBP and NF-κB p65 play critical roles in the switch from osmoadaptive homeostasis to inflammation, respectively. Here we identified PACT-mediated PKR kinase activation as a marker of the termination of adaptation and initiation of inflammation in Mus musculus embryonic fibroblasts. We found that high stress-induced PACT-PKR activation inhibits the interaction between NF-κB c-Rel and TonEBP essential for the increased expression of TonEBP-dependent osmoprotective genes. This resulted in enhanced formation of TonEBP/NF-κB p65 complexes and enhanced proinflammatory gene expression. These data demonstrate a novel role of c-Rel in the adaptive response to hyperosmotic stress, which is inhibited via a PACT/PKR-dependent dimer redistribution of the Rel family transcription factors. Our results suggest that inhibiting PACT-PKR signaling may prove a novel target for alleviating stress-induced inflammatory diseases.

Data availability

Sequencing data have been deposited in GEO under accession code GSE138692.

The following data sets were generated

Article and author information

Author details

  1. Kenneth T Farabaugh

    Pharmacology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9591-0466
  2. Dawid Krokowski

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Bo-Jhih Guan

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Zhaofeng Gao

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Xing-Huang Gao

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0720-3690
  6. Jing Wu

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Raul Jobava

    Biochemistry, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Greeshma Ray

    Inflammation and Immunity, Cleveland Clinic Foundation, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Tristan J de Jesus

    Pathology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Massimiliano G Bianchi

    Medicine and Surgery, Universita degli Studi di Parma, Parma, Italy
    Competing interests
    The authors declare that no competing interests exist.
  11. Evelyn Chukwurah

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. Ovidio Bussolati

    Department of Medicine and Surgery, University of Parma, Parma, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4301-2939
  13. Michael Kilberg

    Biochemistry and Molecular Biology, University of Florida, Gainesville, United States
    Competing interests
    The authors declare that no competing interests exist.
  14. David A Buchner

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3920-4871
  15. Ganes C Sen

    Department of Inflammation and Immunity, Cleveland Clinic Foundation, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  16. Calvin Cotton

    Physiology and Biophysics, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  17. Christine McDonald

    Department of Inflammation and Immunity, Cleveland Clinic Foundation, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  18. Michelle Longworth

    Department of Inflammation and Immunity, Cleveland Clinic Foundation, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  19. Parameswaran Ramakrishnan

    Pathology, Case Western Reserve University, Cleveland, United States
    For correspondence
    pxr150@case.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1314-827X
  20. Maria Hatzoglou

    Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, United States
    For correspondence
    mxh8@case.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2037-1231

Funding

National Institutes of Health (R01DK53307; R01DK060596; R01DK113196)

  • Maria Hatzoglou

National Institute of Allergy and Infectious Diseases (R01AI116730; R21AI144264)

  • Parameswaran Ramakrishnan

National Science Centre (2018/30/E/NZ1/00605)

  • Dawid Krokowski

Cleveland Digestive Disease Research Core Center (DK097948)

  • Maria Hatzoglou

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 Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#400061) of Case Western Reserve University.

Copyright

© 2020, Farabaugh 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. Kenneth T Farabaugh
  2. Dawid Krokowski
  3. Bo-Jhih Guan
  4. Zhaofeng Gao
  5. Xing-Huang Gao
  6. Jing Wu
  7. Raul Jobava
  8. Greeshma Ray
  9. Tristan J de Jesus
  10. Massimiliano G Bianchi
  11. Evelyn Chukwurah
  12. Ovidio Bussolati
  13. Michael Kilberg
  14. David A Buchner
  15. Ganes C Sen
  16. Calvin Cotton
  17. Christine McDonald
  18. Michelle Longworth
  19. Parameswaran Ramakrishnan
  20. Maria Hatzoglou
(2020)
PACT-mediated PKR activation acts as a hyperosmotic stress intensity sensor weakening osmoadaptation and enhancing inflammation
eLife 9:e52241.
https://doi.org/10.7554/eLife.52241

Share this article

https://doi.org/10.7554/eLife.52241

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