Fig. 7. FGF10-coated beads fail to induce Lef1 expression in the epithelium. Organotypic culture after FGF10-coated bead grafting was carried out for 24 hours and followed by whole-mount in situ hybridization to detect Lef1 expression. (A) Two FGF10-coated beads (asterisks) were grafted on the flank of E11.5 embryos. One bead was grafted close to the mammary line and the other one was grafted more dorsally. (B) High magnification of the boxed area in A showing endogenous Lef1 expression in the mammary placode 2 and 3 but no Lef1 induction in the ectoderm surrounding the bead. fl, forelimb; hl, hindlimb. Scale bar, A, 890 µm; B, 170 µm.