MiR-34b-5p Mediates the Proliferation and Differentiation of Myoblasts by Targeting IGFBP2

As key post-transcriptional regulators, microRNAs (miRNAs) play an indispensable role in skeletal muscle development. Our previous study suggested that miR-34b-5p and IGFBP2 could have a potential role in skeletal muscle growth. Our goal in this study is to explore the function and regulatory mechanism of miR-34b-5p and IGFBP2 in myogenesis. In this study, the dual-luciferase reporter assay and Western blot analysis showed that IGFBP2 is a direct target of miR-34b-5p. Flow cytometric analysis and EdU assay showed that miR-34b-5p could repress the cell cycle progression of myoblasts, and miR-34b-5p could promote the formation of myotubes by promoting the expression of MyHC. On the contrary, the overexpression of IGFBP2 significantly facilitated the proliferation of myoblasts and hampered the formation of myotubes. Together, our results indicate that miR-34b-5p could mediate the proliferation and differentiation of myoblasts by targeting IGFBP2.