MUSCLE-SPECIFIC GENE-EXPRESSION DURING EM BRYONIC-DEVELOPMENT

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