The Activation of Akt/protein Kinase B Signaling Affects the Expression of Histone H3 Lysine 27 Methylase and Demethylase Genes in Mouse Cell Lines

摘要

H3K27 methylation plays an important role in the regulation of gene expression and chromatin stability and its expression is dynamically regulated by both specific methylases and demethylases. During development, the regulation of these enzymes is fine-tuned to co-determine the appropriate level of H3K27 methylation thus ensuring correct gene expression. However, it is not completely clear how this regulation is realized. Here, we found that Akt (Akt1 and Akt2), H3K27 methylases (Ezh1 and Ezh2) and demethylases (Jmjd3 and Utx) displayed varying levels of RNA and protein expression in mouse cell lines. Ezh2 was upregulated (p<0.05) at the protein level in an IGF-1-treated C2C12 cell line. The overexpression of p-Akt through myr-Akt vector transfection greatly downregulated the mRNA levels of Ezh1, Jmjd3 and Utx (p<0.01) but not Ezh2 (p>0.05). Therefore, the data suggest that the expression of both H3K27 methylase and demethylase genes is involved in the activation of the IGF-1/PI3K/Akt pathway.