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Updated: Dec 8, 2025
Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
The calmodulin redox sensor controls myogenesis
Alex W Steil1, Jacob W Kailing1, Cade J Armstrong1
1Department of Biology, University of Wisconsin-La Crosse, La Crosse, WI, United States of America.
Abstract:
Muscle aging is accompanied by blunted muscle regeneration in response to injury and disuse. Oxidative stress likely underlies this diminished response, but muscle redox sensors that act in regeneration have not yet been characterized. Calmodulin contains multiple redox sensitive methionines whose oxidation alters the regulation of numerous cellular targets. We have used the CRISPR-Cas9 system to introduce a single amino acid substitution M109Q that mimics oxidation of methionine to methionine sulfoxide in one or both alleles of the CALM1 gene, one of three genes encoding the muscle regulatory protein calmodulin, in C2C12 mouse myoblasts. When signaled to undergo myogenesis, mutated myoblasts failed to differentiate into myotubes. Although early myogenic regulatory factors were present, cells with the CALM1 M109Q mutation in one or both alleles were unable to withdraw from the cell cycle and failed to express late myogenic factors. We have shown that a single oxidative modification to a redox-sensitive muscle regulatory protein can halt myogenesis, suggesting a molecular target for mitigating the impact of oxidative stress in age-related muscle degeneration.
Insights
Oxidative stress impairs muscle regeneration during aging. Researchers found that modifying the calmodulin gene (CALM1) to mimic oxidation halted muscle cell differentiation, suggesting a target for age-related muscle degeneration.
Area of Science:
- Muscle biology and aging research
- Cellular redox signaling
- Molecular genetics
Background:
- Muscle aging is characterized by reduced regeneration capacity following injury or disuse.
- Oxidative stress is implicated in this decline, but specific redox sensors in muscle regeneration remain unidentified.
- Calmodulin, a muscle regulatory protein, possesses methionine residues sensitive to oxidation, potentially affecting its function.
Purpose of the Study:
- To investigate the role of oxidative modification of calmodulin in muscle regeneration.
- To determine if mimicking methionine oxidation in calmodulin impacts myogenesis.
- To identify potential molecular targets for combating age-related muscle degeneration.
Main Methods:
- Utilized CRISPR-Cas9 gene editing in C2C12 mouse myoblasts to create CALM1 mutations (M109Q) mimicking methionine oxidation.
- Assessed myoblast differentiation into myotubes upon induction of myogenesis.
- Analyzed the expression of early and late myogenic regulatory factors and cell cycle withdrawal.
Main Results:
- Myoblasts with the CALM1 M109Q mutation (in one or both alleles) failed to differentiate into myotubes.
- Despite the presence of early myogenic factors, mutated cells did not withdraw from the cell cycle.
- Expression of late myogenic factors was significantly impaired in mutated myoblasts.
Conclusions:
- A single oxidative modification to the redox-sensitive protein calmodulin can arrest myogenesis.
- This finding highlights calmodulin's critical role in muscle differentiation and regeneration.
- Targeting calmodulin's redox state may offer a strategy to mitigate oxidative stress effects in aging muscle.
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