Fig. 5. Wnt5a and Ror2 have an epistatic effect on palate development. (A) An E14.5 wild-type embryo shows the closure of the palate. (B) An E14.5 Ror2^-/- embryo shows a failed palatal elevation. (C) Failed palatal elevation is observed in an E14.5 Ror2^+/-;Wnt5a^+/- embryo. (D-F) Sections through the anterior palate of E13.5 wild-type control (D), Ror2 mutant (E) and Ror2^+/-;Wnt5a^+/- embryo (F) show Shh expression in the MEE of the control palate, but a lack of Shh expression in the MEE of the Ror2^-/- and Ror2^+/-;Wnt5a^+/- palate. Arrows indicate the MEE. (G) The anterior palate of an E13.5 control embryo shows BrdU-labeled cells. (H,I) The level of cell proliferation is similarly increased in the anterior palate of Ror2^-/- (H) and Ror2^+/-;Wnt5a^+/- (I) embryos. The red lines in G-I separate the dorsal and ventral halves of the palate. T, tongue; PS, palatal shelf.