Fig. 5. Expression of markers of palate development in Snai1/2-dko embryos. (A-C) At E13.5, Pax9 is expressed in a dynamic pattern, transitioning from the lateral to medial aspects of the palatal shelf. Both control and mutant embryos show similar expression of an intermediate pattern (A,B), while E14.5 mutant shelves show the full transition to medial expression in the posterior palate (C). (D-F) Msx1 expression at E13.5 is normally restricted to the anterior palatal shelf mesenchyme. Expression of Msx1 appears unaltered in mutant shelves at E13.5 and in the vertically oriented E14.5 shelves. (G-I) Shh expression at E13.5 is localized to the thickened oral epithelium lateral to the vertical palatal shelf. Mutant embryos display the proper pattern at both stages, but the expression level appears somewhat reduced. (J-L) At E13.5 Osr1 is expressed in discrete domains in the lateral palatal shelf mesenchyme (arrows). As with Shh, note the proper patterning, but reduced expression, in mutant embryos. ps, palatal shelf; t, tongue; tb, tooth bud. Scale bar: 200 µm.