Fig. 8. A schematic summarization of the Mesp1/Mesp2 chimera experiments. Mesp1/Mesp2 double-null cells can contribute to neither epithelial somite nor dermomyotome formation, whereas Mesp2-null cells can partially contribute to both somites and dermomyotome. Red outlines indicate epithelialized tissues (epithelial somites, dermomyotomes and abnormal small clusters).