Fig. 6. Characterization of Tam-induced Cre recombinase activity in the surface ectoderm and forming epidermis of K14-Cre-ER^T2 transgenic mice. (A) Whole-mount X-Gal-stained E10.5 K14-Cre-ER^T2(tg/0)/ROSA^fl/+ embryo after (a) oil and (b) 0.1 mg Tam injection to a female at E9.0. fl, forelimb; hl, hindlimb; p, first pharyngeal arch. (B) X-Gal-stained dorsal skin sections of E12.5 (a,b), E14.5 (c,d) and E18.5 (e,f) K14-Cre-ER^T2(tg/0)/ROSA^fl/+ fetuses after daily injections of oil (a,c,e) or Tam (b,d,f) to females from E9.5-E11.5 (a,b), E 9.5-E13.5 (c,d) and E12.5-E16.5 (e,f) days gestation. Sections were counterstained with safranin. E, epidermis; D, dermis; hb, hair bulb. Scale bar in a: 16 µm.