SENP2 and myostatin repress skeletal myogenesis in C2C12 and satellite stem cells. Differentiation of C2C12 cells or satellite stem cells was induced with 2% horse serum, and then NS-siRNA (si-NS), MEF2A siRNA (si-MEF2A), SENP2 siRNA (si-SENP2), or myostatin siRNA (si-myostatin) were used for transfection. The expression of myostatin, MEF2A, or SENP2 in these cells was analyzed by Western blot analysis (A and B). Skeletal myogenesis was analyzed by staining with anti-myosin heavy chain (green) (C). DAPI (blue) was used to stain the cell nucleus.