Probe:	Runx2 probe20
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS21: frontal bone primordium	Present	Regionally restricted	1M	Expression extended slightly to the direction of both apex and base in the wild type.

Structure	Level	Pattern	Image	Note
TS21: frontal bone primordium	Present	Regionally restricted	1N	Expression in the mutant failed to extend apically, its apical tip rather regressed towards the basal side. In contrast, basal side extension did not appear to be affected in the mutant. The expression domain was smaller than the wild type.

Structure	Level	Pattern	Image	Note
TS22: frontal bone primordium	Present	Regionally restricted	1O	Expression extended slightly to the direction of both apex and base in the wild type.

Structure	Level	Pattern	Image	Note
TS22: frontal bone primordium	Present	Regionally restricted	1P	Expression in the mutant failed to extend apically, its apical tip rather regressed towards the basal side. In contrast, basal side extension did not appear to be affected in the mutant. The expression domain was smaller than the wild type.

Structure	Level	Pattern	Image	Note
TS22: frontal bone primordium	Present	Regionally restricted	1Q	Expression extended slightly to the direction of both apex and base in the wild type.

Structure	Level	Pattern	Image	Note
TS22: frontal bone primordium	Present	Regionally restricted	1R	Expression in the mutant failed to extend apically, its apical tip rather regressed towards the basal side. In contrast, basal side extension did not appear to be affected in the mutant. The expression domain was smaller than the wild type.

Structure	Level	Pattern	Image	Note
TS21: frontal bone primordium	Present		3D , 3F , 3A

Structure	Level	Pattern	Image	Note
TS21: frontal bone primordium	Present		3E , 3B , 3G	Decreased BrdU incorporation was observed by osteogenic cells at the apical edge of the Runx2 expression domain.