Expression of transcriptor factors MyoD, Myf5, myogenin and MRF4 forms the basis of myogenesis. In Acrania, Pisces and Amphibia, as in Aves, myogenesis is initiated by MyoD. In Mammalia expression of Myf5 initiates myogenesis. Signal proteins Wnt and Shh induce the expression of genes encoding for MyoD or Myf5. In fishes and amphibians expression of MyoD starts in non-segmented mesoderm and the...
