Probe:	Sox9 probe35
Probe preparation:	Antisense labelled with digoxigenin RNA

Structure	Level	Pattern	Image	Note
TS19: dental placode	Absent		1a	No expression in dental tissue at lamina stage (E11.5).

Structure	Level	Pattern	Image	Note
TS20: dental placode	Absent			No expression in dental tissue at early bud stage (E12.5).

Structure	Level	Pattern	Image	Note
TS21: tooth bud	Present	Regionally restricted	1b	Expression in dental epithelium from late bud stage (E13.5).
TS21: incisor epithelium	Present	Regionally restricted	1b	Expression in dental epithelium from late bud stage (E13.5).

Structure	Level	Pattern	Image	Note
TS22: cap stage tooth	Strong	Regionally restricted	1c	At cap stage (E14.5), strong expression in dental epithelium.
TS22: incisor epithelium	Strong	Regionally restricted	1c	At cap stage (E14.5), strong expression in dental epithelium.
TS22: cervical loop	Present	Regionally restricted	1c	Expression in both labial cervical loop and lingual cervical loop.
TS22: enamel knot	Absent		1c

Structure	Level	Pattern	Image	Note
TS24: incisor epithelium	Present		1d	From early bell (E16.5) to late bell (E18.5) stages, expression in both epithelium and mesenchyme.
TS24: incisor mesenchyme	Present		1d	From early bell (E16.5) to late bell (E18.5) stages, expression in both epithelium and mesenchyme.

Structure	Level	Pattern	Image	Note
TS24: incisor mesenchyme	Strong	Regionally restricted	1d'	Strong expression in dental mesenchyme, especially cells adjacent to epithelium.

Structure	Level	Pattern	Image	Note
TS24: cervical loop	Strong	Regionally restricted	1d"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.
TS24: incisor enamel organ	Strong	Regionally restricted	1d"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.
TS24: outer enamel epithelium	Strong	Regionally restricted	1d"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.
TS24: stellate reticulum	Strong	Regionally restricted	1d"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.

Structure	Level	Pattern	Image	Note
TS26: incisor epithelium	Present		1e	From early bell (E16.5) to late bell (E17.5) stages, expression in both epithelium and mesenchyme.
TS26: incisor mesenchyme	Present		1e	From early bell (E16.5) to late bell (E17.5) stages, expression in both epithelium and mesenchyme.

Structure	Level	Pattern	Image	Note
TS26: incisor mesenchyme	Strong	Regionally restricted	1e'	Strong expression in dental mesenchyme, especially in cells adjacent to epithelium.

Structure	Level	Pattern	Image	Note
TS26: cervical loop	Strong	Regionally restricted	1e"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.
TS26: incisor enamel organ	Strong	Regionally restricted	1e"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.
TS26: outer enamel epithelium	Strong	Regionally restricted	1e"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.
TS26: stellate reticulum	Strong	Regionally restricted	1e"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum, and outer enamel epitheium.

Structure	Level	Pattern	Image	Note
TS27: incisor epithelium	Present		2a	At postnatal days, expression in both epithelium and mesenchyme.
TS27: incisor mesenchyme	Present		2a	At postnatal days, expression in both epithelium and mesenchyme.

Structure	Level	Pattern	Image	Note
TS27: cervical loop	Strong	Regionally restricted	2a'	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum and outer enamel epithelium.
TS27: outer enamel epithelium	Strong	Regionally restricted	2a'	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum and outer enamel epithelium.
TS27: stellate reticulum	Strong	Regionally restricted	2a'	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum and outer enamel epithelium.
TS27: incisor mesenchyme	Strong	Regionally restricted	2a'	Strong expression in dental mesenchyme, especially in cells adjacent to epithelium.

Structure	Level	Pattern	Image	Note
TS28: incisor epithelium	Present		2c	At postnatal days, expression in both epithelium and mesenchyme.
TS28: incisor mesenchyme	Present		2c	At postnatal days, expression in both epithelium and mesenchyme.

Structure	Level	Pattern	Image	Note
TS28: incisor mesenchyme	Strong	Regionally restricted	2c'	Strong expression in dental mesenchyme, especially in cells adjacent to epithelium.

Structure	Level	Pattern	Image	Note
TS28: cervical loop	Strong	Regionally restricted	2c"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum and outer enamel epithelium.
TS28: outer enamel epithelium	Strong	Regionally restricted	2c"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum and outer enamel epithelium.
TS28: stellate reticulum	Strong	Regionally restricted	2c"	Strong expression in labial cervical loop, including basal epithelium, stellate reticulum and outer enamel epithelium.