MiR-34b Regulates Muscle Growth and Development by Targeting SYISL

Non-coding genes, such as microRNA and lncRNA, which have been widely studied, play an important role in the regulatory network of skeletal muscle development. However, the functions and mechanisms of most non-coding RNAs in skeletal muscle regulatory networks are unclear. This study investigated the function and mechanism of <i>miR-34b</i> in muscle growth and development. <i>MiR-34b</i> overexpression and interference tests were performed in C2C12 myoblasts and animal models. It was demonstrated that <i>miR-34b</i> significantly promoted mouse muscle growth and development in vivo, while <i>miR-34b</i> inhibited myoblast proliferation and promoted myoblast differentiation in vitro. Bioinformatics prediction using TargetScan for miRNA target identification and Bibiserv2 for potential miRNA-gene interaction analysis revealed a <i>miR-34b</i> binding site in the <i>SYlSL</i> sequence. The molecular mechanism of <i>miR-34b</i> regulating muscle growth and development was studied by co-transfection experiment, luciferase reporter gene detection, RNA immunoprecipitation, and RNA pull-down. <i>MiR-34b</i> can directly bind to <i>SYISL</i> and AGO2 proteins and regulate the expression of <i>SYISL</i> target genes <i>p21</i> and <i>MyoG</i> by targeting <i>SYISL</i>, thereby regulating muscle growth and development. This study highlights that, as a novel regulator of myogenesis, <i>miR-34b</i> regulates muscle growth and development by targeting <i>SYISL</i>.