Title: Microarray analysis of transgenic mice specifically overexpressing Dnmt3a in skeletal muscle (Dnmt3a Tg mice, young and old)

DNA methylation occurs as 5-methylcytosines mainly at cytosine-guanine dinucleotides, so-called CpG sites, and such methylation is a well-studied epigenetic mechanism for transcriptional regulation. Genomic DNA methylation patterns are established by the actions of the de novo methyltransferases Dnmt3a and Dnmt3b, and are maintained by the methyltransferase Dnmt1. Expression of Dnmt3a mRNA is relatively high in skeletal muscle, suggesting a major role in transcriptional regulation. Thus, we created transgenic mice specifically overexpressing Dnmt3a in skeletal muscle (Dnmt3a Tg mice). In this study, we performed a microarray analysis of skeletal muscle in wild-type control and Dnmt3a Tg mice (young: 3 months of age, female, and old: 26 months of age, female). The microarray data shows upregulation of a set of slow-twitch myofiber-specific genes and downregulation of fast-twitch myofiber-specific genes in Dnmt3a-Tg muscle compared with WT muscle. For microarray analysis, RNA was isolated from the gastrocnemius skeletal muscle of control young mice (3 months of age, female, N=4), control old mice (26 months of age, female, N=8), Dnmt3a Tg young mice (3 months of age, female, N=4), and Dnmt3a Tg old mice (26 months of age, female, N=8).