Deciphering the long noncoding RNAs language in myogenesis: a comprehensive glimpse on Charme

The mammalian genome contains thousands of long noncoding RNAs (lncRNAs), which have been proposed to be fundamental in the regulation of many biological processes. Through an high-throughput transcriptome screening, we identified a subset of new polyadenylated and multi-exonic lncRNAs which result differentially expressed during murine skeletal muscle in vitro differentiation (Ballarino et al., 2015). In particular one candidate, Charme (for Chromatin architect of muscle expression) is an abundant and highly conserved noncoding transcript specifically required for in vitro myogenesis. Mechanistically, Charme acts in the nucleus as a structural RNA, contributing to the formation of chromosome territories where coordinated expression of pro-myogenic genes occurs. Interestingly, Charme ablation in vivo resulted in a very distinct cardiac pathological phenotype in which the morphology of the murine heart is deeply remodelled (Ballarino et al., 2018). We are now working to understand the molecular determinants of this phenotype as well as deepening our knowledge on the human syntenic transcript (hsCharme).