Fig. 6. Dermo1 expression in the flank and ventral subectodermal mesenchyme is induced by β-catenin. (A-L) Section in situ hybridization of Dermo1 mRNA (D-F,J-L) at E10.5 and E11.5; alternate sections are stained with X-gal to visualize En1 lineage-marked cells (A-C;G-I). (J) Dermo1 mRNA is first expressed in the subectodermal flank and ventral mesenchyme, starting at E11.5, in the control embryos. (E,K) In the β-catenin loss-of-function mutants, Dermo1 mRNA is not visible at E10.5 or E11.5. (F,L) By stabilizing β-catenin in the En1 lineage, Dermo1 mRNA is expressed earlier at E10.5, and ectopically in all the mutant cells by E11.5 (dashed line with arrows). Images are of (A-F) E10.5 and (G-L) E11.5 embryos; all insets (F,J,L) are of the same magnification. Compare E and F with D, and K and L with J.