Probe:	Ptc cDNA3
Probe preparation:	Antisense labelled with S35 RNA

Structure	Level	Pattern	Image	Note
TS19: mandibular process	Present	Regionally restricted	1C	Ptc in the molars was restricted to the mesenchyme underlying the tooth thickening. In the mandibular and maxillary incisors, the domain of Ptc appeared to have extended more laterally but was still localized in the odontogenic region of the mandible.
TS19: maxillary process	Present	Regionally restricted	1C	Ptc in the molars was restricted to the mesenchyme underlying the tooth thickening. In the mandibular and maxillary incisors, the domain of Ptc appeared to have extended more laterally but was still localized in the odontogenic region of the mandible.

Structure	Level	Pattern	Image	Note
TS20: mandibular process	Present	Regionally restricted	1I	Ptc was expressed uniformly in the odontogenic epithelium and mesenchyme of the incisors, whereas in the molars the medial pattern of expression was maintained.
TS20: maxillary process	Present	Regionally restricted	1I	Ptc was expressed uniformly in the odontogenic epithelium and mesenchyme of the incisors, whereas in the molars the medial pattern of expression was maintained.

Structure	Level	Pattern	Image	Note
TS21: lower jaw molar	Present	Regionally restricted	1O	In molars, Ptc was expressed in the dental papilla and also in regions of the dental epithelium.
TS21: lower jaw molar epithelium	Present	Regionally restricted	1O	In molars, Ptc was expressed in the dental papilla and also in regions of the dental epithelium.
TS21: upper jaw molar	Present	Regionally restricted	1O	In molars, Ptc was expressed in the dental papilla and also in regions of the dental epithelium.
TS21: upper jaw molar epithelium	Present	Regionally restricted	1O	In molars, Ptc was expressed in the dental papilla and also in regions of the dental epithelium.
TS21: lower jaw tooth	Strong	Regionally restricted	1O	In the dental follicle, Ptc was expressed more strongly on the lingual side of the tooth germs.
TS21: upper jaw tooth	Strong	Regionally restricted	1O	In the dental follicle, Ptc was expressed more strongly on the lingual side of the tooth germs.
TS21: lower jaw incisor	Strong	Regionally restricted	1O	In the incisors, Ptc was also expressed most strongly on the lingual side of the tooth germs.
TS21: upper jaw incisor	Strong	Regionally restricted	1O	In the incisors, Ptc was also expressed most strongly on the lingual side of the tooth germs.

Structure	Level	Pattern	Image	Note
TS22: lower jaw incisor	Present	Regionally restricted	1U	The pattern of expression of Ptc in the molars and incisors resembled that seen at E13.5.
TS22: lower jaw molar	Present	Regionally restricted	1U	The pattern of expression of Ptc in the molars and incisors resembled that seen at E13.5.
TS22: upper jaw incisor	Present	Regionally restricted	1U	The pattern of expression of Ptc in the molars and incisors resembled that seen at E13.5.
TS22: upper jaw molar	Present	Regionally restricted	1U	The pattern of expression of Ptc in the molars and incisors resembled that seen at E13.5.
TS22: enamel organ	Absent		1A' , 1U

Structure	Level	Pattern	Image	Note
TS21: lower jaw molar	Present		8A	Ptc is normally expressed in molar tooth germs.
TS21: upper jaw molar	Present		8A	Ptc is normally expressed in molar tooth germs.

Structure	Level	Pattern	Image	Note
TS22: upper jaw molar epithelium	Absent		8C	Ptc was downregulated in the epithelium.
TS22: lower jaw molar	Present		8C
TS22: upper jaw molar	Present		8C

Structure	Level	Pattern	Image	Note
TS21: lower jaw molar	Strong		8E
TS21: upper jaw molar	Strong		8E

Structure	Level	Pattern	Image	Note
TS21: lower jaw molar	Present		8G
TS21: upper jaw molar	Present		8G
TS21: lower jaw molar epithelium	Moderate		8G	Ptc expression was slightly weaker in the epithelial component.
TS21: upper jaw molar epithelium	Moderate		8G	Ptc expression was slightly weaker in the epithelial component.