<i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutants exhibit craniofacial skeleton defects.

<p>(A-F) Neonates skeleton preparations of newborn <i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutant and control stained with alcian blue and alizarin red; dorsal (A, B), lateral (C, D) and ventral (E, F) views. A suture between frontal bones in control (asterisk in B), but craniosynostosis (A, arrowhead) in<i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutant. (C-F) In <i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutant, the premaxilla(pmx), maxilla (mx) and mandible (ma) are hypoplastic and deformed, the nasal capsule cartilage (nc) is missing, the body of hyoid bone (b-hy) is over-ossified, and the tympanic rings are thickened and deformed. (G, H) The mandible is removed to enhance the view of palatal bone. Palatal bones are fused to form the secondary palate in control (H, dashed line), but severely hypoplastic and cleft in <i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutant (G, dashed lines and asterisk). (I-K) Dissected hyoid and laryngeal skeletons from E14.5 (I), E15.5 (J), and P0 (K) skeletal staining samples. <i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutants exhibit premature ossification in the body of hyoid bone at E15.5, and abnormal ossification in hyoid bone and thyroid cartilage at P0. (L-N) Dissected mandibles from the same embryos shown in Fig 2 I-K. Arrowheads in (L) and (M) indicate the abnormal ossification of incisor tip in <i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutants. The NCCs-derived mandible and tympanic rings are severely malformed, but the mesoderm-derived otic capsule is normal in P0 <i>Wnt1-cre;Gsα</i>^<i>f/f</i> mutant (N). agp, angular process; b-hy, body of the hyoid bone; bo, basioccipital; cdp, condylar process; crp, coronoid process; eo, exoccipital; fr, frontal; gh-hy, greater horn of the hyoid bone; ip, interparietal; lh-hy, lesser horn of the hyoid bone; ma, mandible; mx, maxilla; na, nasal bone; nc, nasal capsule; oc, otic capsule; pmx, premaxilla; pr, parietal; rpMC, rostral process of Meckel’s cartilage; so, supraoccipital; th, thyroid cartilage; tr, tympanic ring.