Myostatin (MSTN) is a negative regulator of skeletal muscle development and plays an important role in muscle development. Fluctuations in gene expression influenced by DNA methylation are critical for homeostatic responses in muscle. However, little is known about the mechanisms underlying this fluctuation regulation and myogenic differentiation of skeletal muscle. Here we report a genome-wide analysis of DNA methylation dynamics in bovine skeletal muscle myogenesis after myostatin editing. We show that, after myostatin editing, an increase in TETs (DNA demethylases) and a concomitant increase in the receptor for activated C kinase 1 (RACK1) control the myogenic development of skeletal muscle. Interestingly, enhancement of PI3K/AKT/mTOR signaling by RACK1 appears to be an essential driver of myogenic differentiation, as it was associated with an increase in myogenic differentiation marker factors (MyHC and MyoG) during muscle differentiation. Overall, our results suggest that loss of myostatin promotes the myogenic differentiation response in skeletal muscle by decreasing DNA methylation of RACK1.

Epigenome editing technology can targeted and reversibly regulate gene activity without altering the DNA sequences. Gene expression can be regulated by tar

Myostatin (MSTN) is a well-established negative regulator of skeletal muscle growth; however, its role in bone metabolism and osteogenic differentiation remains incompletely understood. In this study, untargeted and targeted metabolomic analyses were performed to investigate the metabolic effects of the MSTN^Del73C mutation during osteogenic differentiation of sheep bone marrow mesenchymal stem cells (BMSCs). Metabolomic profiles were analyzed in wild-type and MSTN^Del73C mutant BMSCs at 0, 7, and 14 days of osteogenic induction. During normal osteogenic differentiation, metabolites related to glycerophospholipid metabolism were repeatedly detected among significantly altered features, accompanied by marked increases in multiple lysophospholipid subclasses, including lysophosphatidylcholine (LPC), lysophosphatidylserine (LPS), and lysophosphatidylinositol (LPI). In contrast, MSTN^Del73C mutation was associated with significant reductions in several LPC and LPI species (p < 0.01 or p < 0.001), suggesting altered lipid metabolic profiles during differentiation. Targeted metabolomic validation further confirmed the altered abundance pattern of LPC 18:2. Collectively, these findings suggest that MSTN mutation is closely associated with metabolic remodeling during osteogenic differentiation and suggest potential involvement of glycerophospholipid-related metabolites involved in MSTN-related regulation of sheep BMSC osteogenesis.