Fig. 6. Activation of ß-catenin promotes dorsal otocyst cell fates. (A) Whole-mount in situ hybridization of dorsal otocyst markers in cAct embryos at E9.5. Dlx5, Gbx2 and Msx1 are upregulated in the placodal epithelium, although Dlx5 and Msx1 are downregulated in the most deeply invaginated part of the placode, closest to the ventral midline (asterisks). Borders of the Dlx5 and Gbx2 expressions in control embryos are indicated with bars. Msx1 expression is just starting to appear in the control endolymphatic bud at E9.5 (arrowhead). (B) Pax2 expression in cAct is downregulated at E9.5, while Pax8 is expanded. A dorsal marker, Hmx3, is not expanded. (C) Expression of neurogenic and non-neurogenic markers. Neurod1 and Lfng (anteroventral markers) and Tbx1 (posteroventral marker) are not expressed in cAct embryos. Broken lines represent the malformed otocyst and open rim. Anterior (A) and posterior (P) orientation is indicated with arrows.