Glycine inhibits NINJ1 membrane clustering to suppress plasma membrane rupture in cell death
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.
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
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.
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.
- Carla V Rothlin, Yale University, United States
- Preprint posted: December 12, 2021 (view preprint)
- Received: March 14, 2022
- Accepted: December 5, 2022
- Accepted Manuscript published: December 5, 2022 (version 1)
- Accepted Manuscript updated: December 8, 2022 (version 2)
- Version of Record published: December 15, 2022 (version 3)
© 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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