Figure 5: Foxi3-expressing cells contribute to hair and tooth placodes.

(A-E) Foxi3^GFP reporter expression is seen in the progenitors of whisker follicles at E12.5 and 14.5 (A, B), hair follicles from dissected rump skin at E14.5 (C) and tooth placodes at E12.5 and 14.5 (D,E). (F-K) To label the descendants of these populations, Foxi3^CreER mice were mated with ROSA-Ai9 Cre reporter mice and the pregnant females received a single dose of tamoxifen by gavage at 11.5 dpc (G11.5). Mice were analyzed for tdTomato expression at E14.5 and E18.5. Cells could be observed in the outer root sheath, cortex, and dermal papilla of the whisker follicle (F, F’, I, I’, I”, K) and in the dental and oral epithelium (G, H, J)