Enhanced myogenesis through LncFAM-mediated recruitment of HNRNPL to the MYBPC2 promoter II

We identified a novel muscle-specific lncRNA, lncFAM71E1-2:2 (lncFAM), which increased robustly during early human myogenesis. Overexpression of lncFAM promoted differentiation of human myoblasts into myotubes, while silencing lncFAM suppressed this process. A nucleus-resident lncRNA, lncFAMwas studied using chromatin isolation by RNA purification followed by mass spectrometry (ChIRP-ms) analysis to identify the molecular mechanisms whereby it might promote myogenesis. Analysis of lncFAM-interacting proteins revealed that lncFAM recruited the RNA-binding protein HNRNPL to the promoter of MYPBPC2, in turn increasing MYBPC2 mRNA transcription and enhancing production of the myogenic protein MYPBPC2. These results highlight a mechanism whereby a novel ribonucleoprotein complex, lncFAM-HNRNPL promotes MYBPC2 expression transcriptionally to increase myogenesis Validation of Illumina sequencing by Nanopore RNA-sequencing of a single human myoblast control sample