Post-transcriptional regulation of satellite cell quiescence by TTP-mediated mRNA decay
- Ampio Pharmaceuticals, Inc., United States
- University of Colorado, United States
- University of Colorado Boulder, United States
Abstract
Skeletal muscle satellite cells in their niche are quiescent and upon muscle injury, exit quiescence, proliferate to repair muscle tissue, and self-renew to replenish the satellite cell population. To understand the mechanisms involved in maintaining satellite cell quiescence, we identified gene transcripts that were differentially expressed during satellite cell activation following muscle injury. Transcripts encoding RNA binding proteins were among the most significantly changed and included the mRNA decay factor Tristetraprolin. Tristetraprolin promotes the decay of MyoD mRNA, which encodes a transcriptional regulator of myogenic commitment, via binding to the MyoD mRNA 3' untranslated region. Upon satellite cell activation, p38α/β MAPK phosphorylates MAPKAP2 and inactivates Tristetraprolin, stabilizing MyoD mRNA. Satellite cell specific knockdown of Tristetraprolin precociously activates satellite cells in vivo, enabling MyoD accumulation, differentiation and cell fusion into myofibers. Regulation of mRNAs by Tristetraprolin appears to function as one of several critical post-transcriptional regulatory mechanisms controlling satellite cell homeostasis.
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Author details
Reviewing Editor
- Margaret Buckingham, Institut Pasteur, France
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) protocols (#1012.01, #1104.08) of the University of Colorado-Boulder.
Version history
- Received: May 16, 2014
- Accepted: March 26, 2015
- Accepted Manuscript published: March 27, 2015 (version 1)
- Version of Record published: April 30, 2015 (version 2)
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Post-transcriptional regulation of satellite cell quiescence by TTP-mediated mRNA decay
eLife 4:e03390.
https://doi.org/10.7554/eLife.03390
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