miR-143: A Novel Regulator of MyoD Expression in Fast and Slow Muscles of Siniperca chuatsi

The fast and slow skeletal muscle fibers in fish are separated to a much greater degree than in mammals. MyoD is required for the maintenance of normal fiber type balance in muscles. So far, the upstream regulatory factors of MyoD in terms of controlling muscle phenotype are poorly understood. In the present study, we used Siniperca chuatsi as a model system and demonstrated that miR-143 expression was negatively correlated with MyoD expression in the fast and slow muscles of S. chuatsi. The luciferase reporter assay further verified the direct interaction between the miR-143 and MyoD. The miR-143 suppression also led to the significant increase in MyoD and fast myosin heavy chain gene expression in vivo. Taken together, our studies indicated that miRNA participates in controlling the performance of different muscle fiber types in vertebrates.