Glycine inhibits NINJ1 membrane clustering to suppress plasma membrane rupture in cell death

  1. Jazlyn P Borges
  2. Ragnhild SR Sætra
  3. Allen Volchuk
  4. Marit Bugge
  5. Pascal Devant
  6. Bjørnar Sporsheim
  7. Bridget R Kilburn
  8. Charles L Evavold
  9. Jonathan C Kagan
  10. Neil M Goldenberg
  11. Trude Helen Flo
  12. Benjamin Ethan Steinberg  Is a corresponding author
  1. Hospital for Sick Children, Canada
  2. Norwegian University of Science and Technology, Norway
  3. Ragon Institute of MGH, MIT and Harvard, United States
  4. Boston Children's Hospital, United States

Abstract

First recognized more than 30 years ago, glycine protects cells against rupture from diverse types of injury. This robust and widely observed effect has been speculated to target a late downstream process common to multiple modes of tissue injury. The molecular target of glycine that mediates cytoprotection, however, remains elusive. Here, we show that glycine works at the level of NINJ1, a newly identified executioner of plasma membrane rupture in pyroptosis, necrosis, and post-apoptosis lysis. NINJ1 is thought to cluster within the plasma membrane to cause cell rupture. We demonstrate that the execution of pyroptotic cell rupture is similar for human and mouse NINJ1, and that NINJ1 knockout functionally and morphologically phenocopies glycine cytoprotection in macrophages undergoing lytic cell death. Next, we show that glycine prevents NINJ1 clustering by either direct or indirect mechanisms. In pyroptosis, glycine preserves cellular integrity but does not affect upstream inflammasome activities or accompanying energetic cell death. By positioning NINJ1 clustering as a glycine target, our data resolve a long-standing mechanism for glycine-mediated cytoprotection. This new understanding will inform the development of cell preservation strategies to counter pathologic lytic cell death.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files, which includes the source data for the manuscript figures.

Article and author information

Author details

  1. Jazlyn P Borges

    Program in Neuroscience and Mental Health, Hospital for Sick Children, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Ragnhild SR Sætra

    Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8248-0460
  3. Allen Volchuk

    Program in Cell Biology, Hospital for Sick Children, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Marit Bugge

    Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
    Competing interests
    The authors declare that no competing interests exist.
  5. Pascal Devant

    Ragon Institute of MGH, MIT and Harvard, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Bjørnar Sporsheim

    Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
    Competing interests
    The authors declare that no competing interests exist.
  7. Bridget R Kilburn

    Program in Neuroscience and Mental Health, Hospital for Sick Children, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0171-9370
  8. Charles L Evavold

    Ragon Institute of MGH, MIT and Harvard, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Jonathan C Kagan

    Division of Gastroenterology, Boston Children's Hospital, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2364-2746
  10. Neil M Goldenberg

    Program in Cell Biology, Hospital for Sick Children, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2785-1852
  11. Trude Helen Flo

    Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2569-0381
  12. Benjamin Ethan Steinberg

    Program in Neuroscience and Mental Health, Hospital for Sick Children, Toronto, Canada
    For correspondence
    benjamin.steinberg@sickkids.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3070-0548

Funding

International Anesthesia Research Society (Mentored Research Award)

  • Benjamin Ethan Steinberg

Department of Anesthesiology and Pain Medicine, University of Toronto (Early Investigator Award)

  • Benjamin Ethan Steinberg

Research Council of Norway (287696,223255)

  • Trude Helen Flo

Ragon Institute of MGH, MIT and Harvard (Ragon Early Independence Fellowship)

  • Charles L Evavold

National Institutes of Health (AI133524,AI093589,AI116550,and P30DK3485)

  • Jonathan C Kagan

Boehringer Ingelheim Fonds (PhD Fellowship)

  • Pascal Devant

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

Ethics

Animal experimentation: All animal studies were approved by the Hospital for Sick Children Animal Care Committee (AUP #47781).

Human subjects: All human studies were conducted according to the principles expressed in the Helsinki Declaration and approved by the Regional Committee for Medical and Health Research Ethics (No. 2009/2245). Informed consent was obtained from all subjects prior to sample collection.

Reviewing Editor

  1. Carla V Rothlin, Yale University, United States

Version history

  1. Preprint posted: December 12, 2021 (view preprint)
  2. Received: March 14, 2022
  3. Accepted: December 5, 2022
  4. Accepted Manuscript published: December 5, 2022 (version 1)
  5. Accepted Manuscript updated: December 8, 2022 (version 2)
  6. Version of Record published: December 15, 2022 (version 3)

Copyright

© 2022, Borges 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. Jazlyn P Borges
  2. Ragnhild SR Sætra
  3. Allen Volchuk
  4. Marit Bugge
  5. Pascal Devant
  6. Bjørnar Sporsheim
  7. Bridget R Kilburn
  8. Charles L Evavold
  9. Jonathan C Kagan
  10. Neil M Goldenberg
  11. Trude Helen Flo
  12. Benjamin Ethan Steinberg
(2022)
Glycine inhibits NINJ1 membrane clustering to suppress plasma membrane rupture in cell death
eLife 11:e78609.
https://doi.org/10.7554/eLife.78609

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