Maged1, a new regulator of skeletal myogenic differentiation and muscle regeneration.
BACKGROUND
In normal adult skeletal muscle, cell turnover is very slow. However, after an acute lesion or in chronic pathological conditions, such as primary myopathies, muscle stem cells, called satellite cells, are induced to proliferate, then withdraw definitively from the cell cycle and fuse to reconstitute functional myofibers.


RESULTS
We show that Maged1 is expressed at very low levels in normal adult muscle but is strongly induced after injury, during the early phase of myoblast differentiation. By comparing in vitro differentiation of myoblasts derived from wild-type or Maged1 knockout mice, we observed that Maged1 deficiency results in reduced levels of p21CIP1/WAF1, defective cell cycle exit and impaired myotube maturation. In vivo, this defect results in delayed regeneration of injured muscle.


CONCLUSIONS
These data demonstrate for the first time that Maged1 is an important factor required for proper skeletal myoblast differentiation and muscle healing.
Nguyen
Tuan H N
TH
Unité de Recherche en Physiologie Moléculaire, Namur Research Institute for Life Sciences, FUNDP school of Medicine, University of Namur, 21 rue de Bruxelles, Namur B-5000, Belgium.
Bertrand
Mathieu J M
MJ
Sterpin
Christiane
C
Achouri
Younes
Y
De Backer
Olivier R Y
OR
D000818:Animals; D002453:Cell Cycle / Q000235:genetics; D002460:Cell Line; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008817:Mice, Mutant Strains; D024510:Muscle Development; D018485:Muscle Fibers, Skeletal / Q000378:metabolism; D018482:Muscle, Skeletal / Q000293:injuries / Q000378:metabolism* / Q000473:pathology; D009135:Muscular Diseases / Q000473:pathology / Q000503:physiopathology; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D012038:Regeneration; D032496:Satellite Cells, Skeletal Muscle
C493957:Cdkn1a protein, mouse; D050759:Cyclin-Dependent Kinase Inhibitor p21; C486541:Maged1 protein, mouse; D009363:Neoplasm Proteins