Fig. 4

DLX expression in the pharyngeal arches in chick and mouse embryos. a Side view of a HH21 chick embryo showing DLX2 expression throughout the dorsoventral extent of all the pharyngeal arches. b Longitudinal section through the arches showing DLX2 expression in the ectomesenchyme of the arches. c Side view of a TS16 mouse embryo showing pronounced expression of Dlx2 in the first two arches, but much reduced expression in the posterior arches. d Side view of a HH21 chick embryo showing DLX6 expression in the mid region of the three most anterior arches but not the most posterior arches. e Longitudinal section through the arches showing DLX6 expression in the ectomesenchyme of the three most anterior arches. f Side view of a TS16 mouse embryo showing high levels of Dlx6 in the mid region of the first two arches, but much reduced expression in the posterior arches. g Side view of a HH21 chick embryo showing DLX3 expression in the more distal region of the two most anterior arches but not those lying posteriorly. h Longitudinal section through the arches showing DLX3 expression in the ectomesenchyme of the two most anterior arches. f Side view of a TS16 mouse embryo showing high levels of Dlx3 in the distal region of the anterior two arches, but much reduced expression in the posterior arches. Scale bar = 0.1 mm