Myogenin, is a transcriptional activator encoded by the MYOG gene. Myogenin is a muscle-specific basic-helix-loop-helix (bHLH) transcription factor involved in the coordination of skeletal muscle development or myogenesis and repair. Myogenin is a myogenic regulatory factor (MRF), other examples of which also include MyoD, Myf5, and MRF4.