Probe:	Olig3 cDNA2
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS15: neural tube	Present	Regionally restricted	1A	Expression was detected exclusively in the dorsal-most portion of the neural tube.

Structure	Level	Pattern	Image	Note
TS17: neural tube	Present	Regionally restricted	1B	Expression was detected exclusively in the dorsal-most portion of the neural tube.

Structure	Level	Pattern	Image	Note
TS19: future spinal cord	Present	Regionally restricted	1C	Three distinct spots of expression appeared in the ventral spinal cord. The ventral expression was positioned between the ventricular zone and the mantle layer.
TS19: neural tube mantle layer	Present	Regionally restricted	1C	The expression domain in the dorsal spinal cord was reduced in size. Signal in the dorsal-most region was observed both in the ventricular zone and the mantle layer.
TS19: neural tube ventricular layer	Present	Regionally restricted	1C	The expression domain in the dorsal spinal cord was reduced in size. Signal in the dorsal-most region was observed both in the ventricular zone and the mantle layer.

Structure	Level	Pattern	Image	Note
TS20: spinal cord	Present	Regionally restricted	1E , 1D	Expression was detected in the dorsal spinal cord in a region lateral to the roof plate, which was further reduced in size compared to E11.5, and in three ventral clusters.
TS20: spinal cord mantle layer	Present	Regionally restricted	1E , 1D	Expression was detected in the dorsal spinal cord in a few cells arranged dorsoventrally in the medial part of the mantle layer

Structure	Level	Pattern	Image	Note
TS21: spinal cord mantle layer	Present	Single cells	1F	Dorsal-most expression was restricted to a few cells aligned along the outer edge of the ventricular zone in a discontinuous cell strand. Signal was divided into dorsal and ventral groups in the mantle layer.

Structure	Level	Pattern	Image	Note
TS22: spinal cord	Present	Regionally restricted	1H , 1G	Expression was detected in the intermediate and ventromedial parts of the spinal cord, and in the posterior median septum. The dorsal horn only had expressing cells in the basal portion.

Structure	Level	Pattern	Image	Note
TS23: spinal cord	Present	Regionally restricted	1I	Expression was mostly restricted to the ventromedial part of the spinal cord with only a few cells at the intermediate level.