The gene expressions of DNA methylation/demethylation enzymes and cytochrome c oxidase subunit 4 in skeletal muscle of thyroidectomized rats

Abstract

A decrease in mRNA levels for cytochrome c oxidase (COX) subunits was observed in skeletal muscle of hypothyroid rats. However, the precise expression mechanisms of the related genes in hypothyroid state still remain unclear. This study investigated gene expressions of DNA methyltransferases
(Dnmts), DNA demethylases and Cox4 in skeletal muscle of thyroidectomized rats. The findings showed that, the mRNA levels of genes encoding Dnmts and DNA demethylases were up-regulated while the mRNA levels of Cox4 down-regulated. These results imply that, DNA methylation might   down-regulate Cox4 expression and induce a compensatory mechanism for avoiding an excessive incorporation of 5- mC into DNA.

Key words: Gene expression, Dnmts, Mbd4, Gadd45á, Cox4.