Figure 1. Expression of Scube3 and Shh in the early craniofacial region.

Radioactive in situ hybridization on frontal sections. (A–D) Scube3 expression. (A, B) At E10.5, expression is seen primarily in early ectoderm of the facial processes with transcripts also dispersed within the underlying mesenchyme; (C, D) At E11.5, expression is seen throughout the oral ectoderm, including early thickenings of the developing tooth germs, and in the craniofacial mesenchyme. (E–H) Shh expression. Regions of overlap between Shh and Scube3 transcription are indicated by red arrows and include: (E, F) At E10.5, ectoderm of the medial nasal and maxillary processes in the midline; (G, H) At E11.5, ectoderm at the base of the nasal pits and early ectoderm of the developing teeth. fnp, fronto-nasal process; lnp, lateral nasal process; md, mandibular process; mdi, mandibular incisor tooth germs; mnp, medial nasal process; mx, maxillary process; mxm, maxillary molar tooth germs; np, nasal pit; oe, oral ectoderm.