Pax2/8 proteins coordinate sequential induction of otic and epibranchial placodes through differential regulation of foxi1, sox3 and fgf24

►Pax8 and Sox3 are initially coinduced in the otic placode by hindbrain Fgf. ►Pax8 promotes otic development by autonomously downregulating foxi1. ►Pax8 also induces otic expression of fgf24, which locally downregulates sox3. ►Fgf24 also induces epibranchial development by activating sox3 in adjacent ectoderm.