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Updated: Jul 3, 2026
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Identification of MyoD Interactome Using Tandem Affinity Purification Coupled to Mass Spectrometry
Published on: May 17, 2016
A highly conserved molecular switch binds MSY-3 to regulate myogenin repression in postnatal muscle
Libera Berghella1, Luciana De Angelis, Tristan De Buysscher
1Institute of Cell Biology and Tissue Engineering, San Raffaele Biomedical Science Park, Rome 00128, Italy. libera.berghella@spr-r.it
Genes & Development
|August 5, 2008
Summary
Muscle differentiation involves myogenin regulation. A specific DNA element (myogHCE) and protein (MSY-3) are crucial for repressing myogenin after birth, ensuring proper muscle maturation.
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- Myogenin is a key regulator of muscle differentiation.
- Postnatal muscle maturation involves down-regulation of myogenin.
- Understanding the mechanisms of myogenin repression is vital for muscle development research.
Purpose of the Study:
- To investigate the regulatory elements and factors involved in postnatal repression of myogenin.
- To elucidate the role of the myogenin cis-acting element (myogHCE) and MSY-3 protein in muscle maturation.
- To propose a model for myogenin's opposing regulatory functions during muscle development.
Main Methods:
- Analysis of a conserved DNA cis-acting element (myogHCE) in transgenic animals.
- In vivo electroporation to assess the function of myogHCE and MSY-3.
- C2C12 cell culture experiments to study the effects of MSY-3 manipulation on differentiation.
- Chromatin immunoprecipitation assays to determine protein binding to myogHCE.
Main Results:
- A conserved 17-bp DNA element (myogHCE) upstream of the myogenin promoter is essential for postnatal repression.
- The Y-box protein MSY-3 mediates this repression.
- Ectopic MSY-3 inhibits differentiation, while reduced MSY-3 promotes premature differentiation in C2C12 cells.
- MSY-3 and Pbx protein bind to myogHCE in postnatal innervated muscle.
Conclusions:
- The myogHCE motif acts as a molecular switch controlling myogenin expression.
- Opposing functions of myogHCE are mediated by different protein complexes: MyoD/Pbx for activation and MSY-3/Pbx for repression.
- This switch mechanism is critical for regulating muscle differentiation and maturation postnatally.
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