Transcriptomic and epigenomics atlas of myotubes reveals insight into the circadian control of metabolism and development.

Innate circadian rhythms are critical for optimal tissue-specific functions, including skeletal muscle, a major insulin-sensitive tissue responsible for glucose homeostasis. We determined whether transcriptional oscillations are associated with CpG methylation changes in skeletal muscle. We performed rhythmicity analysis on the transcriptome and CpG methylome of circadian synchronized myotubes. We identified several transcripts and CpG-sites displaying oscillatory behavior, which were enriched with Gene Ontology terms related to metabolism and development. Oscillating CpG methylation was associated with rhythmic expression of 31 transcripts. Although circadian oscillations may be regulated by rhythmic DNA methylation, strong rhythmic associations between transcriptome and CpG methylation were not identified. This resource constitutes a transcriptomic/epigenomic atlas of skeletal muscle and regulation of circadian rhythms.