Sonic Hedgehog induces proliferation of committed skeletal muscle cells in the chick limb.

@article{Duprez1998SonicHI,
  title={Sonic Hedgehog induces proliferation of committed skeletal muscle cells in the chick limb.},
  author={Daniel Duprez and Claire Fournier-Thibault and Nicole M. Le Douarin},
  journal={Development},
  year={1998},
  volume={125 3},
  pages={495-505}
}
Myogenic Regulatory Factors (MRFs) are a family of transcription factors whose expression in a cell reflects the commitment of this cell to a myogenic fate before any cytological sign of muscle differentiation is detectable. Myogenic cells in limb skeletal muscles originate from the lateral half of the somites. Cells that migrate away from the lateral part of the somites to the limb bud do not initially express any member of the MRF family. Expression of MRFs in the muscle precursor cells… CONTINUE READING