miR-708-5p Regulates Myoblast Proliferation and Differentiation

SIMPLE SUMMARY: Skeletal muscle is a crucial component of an animal’s body. Its growth and development process are modified by a variety of regulatory factors and signaling pathways. It is reported that miR-708-5p is closely related to cancer, osteoporosis, and muscle development. However, the molecular mechanism of miR-708-5p-mediated regulation of myoblast proliferation and differentiation remains unclear. This research aims to investigate the function of miR-708-5p in the proliferation and differentiation of C2C12 myoblasts and analyze its target genes. After interference or overexpression of miR-708-5p, we found that overexpression of miR-708-5p inhibited myoblast proliferation and promoted C2C12 myoblast differentiation. A total of 253 target genes of miR-708-5p were identified. GO and KEGG pathway analysis suggested that these target genes were significantly enriched in terms related to muscle growth and development. Pik3ca, Pik3r3, and Irs1 were identified as the key target genes of miR-708-5p. These results deepen our understanding of the molecular mechanism of skeletal muscle development and provide a theoretical foundation for further exploring the mechanism of miR-708-5p-mediated regulation of skeletal muscle development. ABSTRACT: MicroRNAs (miRNAs) are key regulators involved in the myogenic process in skeletal muscles. miR-708-5p plays an important role in various biochemical and physiological processes, but its function in skeletal myogenesis remain unclear. In this study, we first explored the effects of miR-708-5p on C2C12 proliferation and differentiation by overexpression and interference experiments. Then, we predicted the target genes of miR-708-5p and analyzed their function. We found that miR-708-5p was gradually increased during myoblast differentiation. Overexpression of miR-708-5p significantly inhibited cell proliferation and promoted the differentiation of myoblasts. A total of 253 target genes were predicted using a bioinformatics approach. These genes were significantly enriched in muscle growth-related GO terms and KEGG pathways, such as actin filament organization, actin cytoskeleton organization, PI3K-Akt pathway, insulin pathway, and Jak-STAT pathway. Among them, Pik3ca, Pik3r3, and Irs1 were considered to be the key target genes of miR-708-5p. To sum up, miR-708-5p inhibited C2C12 cells proliferation and promoted C2C12 cells differentiation. Its target genes significantly enriched in GO terms and KEGG pathways related to the development and growth of muscle. Our results provided a basis for studies on the function and mechanism of miR-708-5p regulating skeletal muscle growth and development.