Description
Skeletal muscle differentiation is a highly coordinated multistep process in which proliferating mononucleated myoblasts rst withdraw from the cell cycle, then differentiate into postmitotic mononucleated myocytes, and subsequently fuse into multinucleated myotubes which nally bundle to form mature muscle bers. All these processes are controlled by the sequential activation of myogenic regulatory factors, and especially MYOD1 is activated in the early phase to promote the transcription of muscle-specific genes coding for muscle proteins such as alpha-actin, myosin heavy chain and muscle creatine kinase.