Gene silencing by S-adenosylmethionine in muscle differentiation

A well-characterised experimental system, the myogenin gene in C2C12 muscle cell culture, was chosen to better understand the methylation mechanism un derlying the regulation of gene expression. We already demonstrated that de methylation dynamics of a specific CpG site in the 5'-flanking region of my ogenin well correlates with gene expression and terminal differentiation. H ere we demonstrate that S-adenosylmethionine-sulphate-p-toluenesulphonate ( SAM) inhibits myogenin expression and myoblast differentiation by delaying the demethylation of specific CpG in differentiating myoblasts. These resul ts suggest new perspectives in methylation mechanisms and the use of SAM in the partial silencing of gene expression, as it could be required in disea se treatment. (C) 2001 Published by Elsevier Science B.V. on behalf of the Federation of European Biochemical Societies.