The IRE1/XBP1 signaling axis promotes skeletal muscle regeneration through a cell non-autonomous mechanism
- University of Houston, United States
- St Ambrose University, United States
- Kanazawa Medical University, Japan
Abstract
Skeletal muscle regeneration is regulated by coordinated activation of multiple signaling pathways activated in both injured myofibers and satellite cells. The unfolded protein response (UPR) is a major mechanism that detects and alleviates protein-folding stresses in ER. However, the role of individual arms of the UPR in skeletal muscle regeneration remain less understood. In the present study, we demonstrate that IRE1α (also known as ERN1) and its downstream target, XBP1, are activated in skeletal muscle of mice upon injury. Myofiber-specific ablation of IRE1 or XBP1 in mice diminishes skeletal muscle regeneration that is accompanied with reduced number of satellite cells and their fusion to injured myofibers. Ex vivo cultures of myofiber explants demonstrate that ablation of IRE1α reduces the proliferative capacity of myofiber-associated satellite cells. Myofiber-specific deletion of IRE1α dampens Notch signaling and canonical NF-kB pathway in skeletal muscle of mice. Our results also demonstrate that targeted ablation of IRE1α reduces skeletal muscle regeneration in the mdx mice, a model of Duchenne muscular dystrophy. Collectively, our results reveal that the IRE1α-mediated signaling promotes muscle regeneration through augmenting the proliferation of satellite cells in a cell non-autonomous manner.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting file.
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Author details
Funding
National Institute of Arthritis and Musculoskeletal and Skin Diseases (AR059810)
- Ashok Kumar
National Institute of Arthritis and Musculoskeletal and Skin Diseases (AR068313)
- Ashok Kumar
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 in 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) protocol (PROT20190043) of the University of Houston. All surgery was performed under Isoflurane, and every effort was made to minimize suffering.
Copyright
© 2021, Roy 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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The IRE1/XBP1 signaling axis promotes skeletal muscle regeneration through a cell non-autonomous mechanism
eLife 10:e73215.
https://doi.org/10.7554/eLife.73215
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