Figure 9. Misactivation of Hh signaling detrimentally affects MR invagination and hair follicle suppression in females and eradication of MRs in males.

X-Gal stained whole-mounts (A–E) and sections (F-H) of Gli2^1ki/1ki;Gli3^xt/+;Gli1^lzki/+ embryos were examined at E18.5. In whole-mounts of female skins, MR#2 protruded prominently and showed encroachment of hair follicles inappropriately close to the evaginated MR (A). Examination of male skin whole-mounts revealed retention of MR#1, #2 and #4 at low (B) and high power (C, D, E respectively), similar to that seen in Gli3^xt/xt;Gli1^lzki/+ embryos. Serial sections through a male MR#2 from Gli2^1ki/1ki;Gli3^xt/+;Gli1^lzki/+ embryos showed Gli1-LacZ-positive hair follicles close to the protruding bud (F; NFR counterstain) and weak expression of Tenascin C (G) and loss of AR (H) by immunohistochemistry.