LncRNA GTL2 regulate myoblast proliferation and differentiation through PKA-CREB pathway in Duolang sheep

Long non-coding RNAs (lncRNAs) represent a category of non-coding RNA longer than 200 nucleotides, which are involved in a variety of biological process such as growth and development. Although several studies have been performed to explore the function of lncRNA in skeletal muscle development, the regulatory mechanisms underlying ovine skeletal muscle development remains unclear. Here, we conducted the expression profiles of lncRNAs from skeletal muscle of 90-day-old embryos (F90), 1-month-old lamb (L30) and 3-year-old adult sheep (A3Y) using RNA sequencing method. In total, 4,738 lncRNAs were identified, including 997 differentially expressed (DE) lncRNAs. Short-time series expression miner (STEM) analysis revealed eight significantly different expression profiles and a set of potential functional lncRNAs related to muscle development. KEGG enrichment analysis revealed that the predicted target genes of lncRNAs were mainly enriched in pathways associated with muscle development, such as cAMP signaling pathways and Wnt signaling pathways. Notably, the expression of lncRNA GTL2 decreased during muscle development in sheep. Moreover, lncRNA GTL2 that we found to be highly expressed in differentiation of skeletal muscle satellite cells (SCs). Indeed, we found lncRNA GTL2 modulate ovine myogenesis through affecting the phosphorylation level of PKA and CREB. Further, lncRNA GTL2 regulates the proliferation and differentiation of SCs through PKA-CREB signaling pathway. On the whole, our study provides a valuable data resource and offer insights into exploring the function and mechanisms of lncRNAs in ovine skeletal muscle development and growth.