[Muscle specific gene expression during embryonal development].

The myogenic bHLH-proteins play a crucial role in the determination and tissue specific gene expression in skeletal muscle. Being able to regulate themselves and the other members of their family they establish the myogenic lineage in the precursor cells of the skeletal muscle. The precise mechanisms that lead to the manifestation of myogenic cells in vivo are still unknown, but much has been learned from the behaviour of established cell lines and targeted mutations in the myogenic regulatory factors (MRFs). This review will focus on the results of these experiments and outline the major regulatory pathways which lead to the formation of skeletal muscle cells.