Expression of <i>Shh</i> and β-catenin Transcripts in Normal <i>(Apc^CKO/CKO)</i> and Mutant <i>(K14-cre; Apc^CKO/CKO)</i> Embryonic Skin

<p>(A–D) Section ISH with <i>Shh</i> probe in E14.5 normal (A), E14.5 mutant (B), E16.5 normal (C), and E16.5 mutant (D) skin. Broken lines indicate the interface between epithelium and mesenchyme. Scale bars: 50 μm. Whole mount in situ detection of β-catenin in E15.5 normal (E, G), mutant (F, H) embryos. Aberrant initiation of multiple hair placodes is evident at E14.5. Loss of <i>K14</i>-driven <i>Apc</i> loss caused aberrant pattern formation (F′) and formed ectopic hair placodes in normally hairless foot pads (H, arrows) which are absent in normal (G).