Fig. 6. Control of neural crest development by MEF2C. Signaling by
endothelin 1 (EDN1) through the ET-A receptor (EDNRA) activates MEF2C
expression in the neural crest. MEF2C directly activates the expression of
DLX5 and DLX6, which regulate the expression of HAND2. Together, these factors
regulate the expression of genes required for craniofacial development.