Probe:	Six4 probe3
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS19: lateral lingual swelling epithelium	Present	Regionally restricted	1A	Epithelial expression in lateral lingual swellings first appearing in mandible at E11.5.

Structure	Level	Pattern	Image	Note
TS20: tongue epithelium	Weak	Regionally restricted	1B	Weak expression in dorsal epithelium of tongue.
TS20: tongue muscle	Weak		1B
TS20: eye	Strong		1B
TS20: telencephalon	Strong		1B

Structure	Level	Pattern	Image	Note
TS25: tongue muscle	Present

Structure	Level	Pattern	Image	Note
TS22: fungiform papillae	Present	Regionally restricted	1C	Expression in apical epithelium of papillae.

Structure	Level	Pattern	Image	Note
TS24: fungiform papillae	Weak	Regionally restricted	1D	Weak expression limited to papillary epithelium.

Structure	Level	Pattern	Image	Note
TS26: fungiform papillae	Absent			By E18.5, no expression in any fungiform papillae.

Structure	Level	Pattern	Image	Note
TS21: oral epithelium	Present	Widespread	1E	Expression in entire oral epithelium.
TS21: tongue papillary placode	Present	Regionally restricted	1E	Expression in epithelial thickening of presumptive circumvallate papilla, but not in invaginated area
TS21: tongue epithelium	Present	Regionally restricted	1E	Expression in surrounding epithelium.

Structure	Level	Pattern	Image	Note
TS23: circumvallate papillae	Strong	Regionally restricted	1F	Strong expression in invaginating trenches, but not in papillary epithelium.

Structure	Level	Pattern	Image	Note
TS26: circumvallate papillae	Strong	Regionally restricted	1G	Intense expression in bottom of trenches.
TS26: salivary gland	Present	Regionally restricted	1G	Expression in von Ebner's glands.

Structure	Level	Pattern	Image	Note
TS27: circumvallate papillae	Ambiguous			Authors state expression had almost disappeared by postnatal day 0.

Structure	Level	Pattern	Image	Note
TS23: tongue papillae	Present	Regionally restricted	1H	Expression in trench epithelium of prospective foliate papilla. Weak expression in dorsal epithelium.

Structure	Level	Pattern	Image	Note
TS26: foliate papillae	Strong	Regionally restricted	1I	Intense expression limited to bottoms of trenches.