Phenotype of X<i>^{Porcn-Ex3-7-flox}</i>/Y;<i>Krt14-Cre</i> mice.

<p>(<b>A, B</b>) Extensive alopecia of X<i>^{Porcn-Ex3-7-flox}</i>/Y;<i>Krt14-Cre</i> (Krt14cKO) compared to wild type (control) at P7. (<b>C–E</b>) Variable dental phenotype (missing and hypoplastic teeth) in Krt14cKO mice. (<b>F–I</b>) RNA <i>in situ</i> hybridization with a <i>Porcn</i> antisense (F, G) and sense (H, I) riboprobe to E16.5 Krt14cKO (G, I) and control (F, H) skin showing reduced <i>Porcn</i> expression in mutant. (<b>J, K</b>) H&E staining of dorsal skin of Krt14cKO (K) and control (J) mice at P9 shows lack of hair follicles in the Krt14cKO mice. (<b>L, M</b>) H&E staining of dorsal skin from newborn (NB) <i>β-catenin</i>^flox/⁺;<i>Krt14-Cre</i> (β-catenin Krt14cKO; M) and control (L) mice also shows lack of hair follicles in the mutant. (<b>N, O</b>) H&E staining of skin from Krt14cKO (O) and control (N) mice at E16.5 shows that the early step of hair follicle morphogenesis does not take place in the Krt14cKO mice. hf, hair follicle. (<b>P, Q</b>) Immunostaining of skin at E16.5 shows that the Krt14cKO epidermis (Q) lacks Sox9-positive cells, which mark the hair follicle from the earliest budding stage (placode). (<b>R, S</b>) Skin of Krt14cKO epidermis (S) at E16.5 also lacks P-cadherin-positive cells, also indicating that placode formation is drastically compromised. Scale bars: F–I and L–S, 50 µm; J and K, 500 µm.