Probe:	pI22AR.3
Probe preparation:	Antisense labelled with digoxigenin RNA

Structure	Level	Pattern	Image	Note
TS13: neural tube	Present		1A

Structure	Level	Pattern	Image	Note
TS15: neural tube	Present	Regionally restricted	1B	Expressed in the dorsal portion extending along the anteroposterior axis to the mesencephalon.
TS15: future hindbrain	Present	Regionally restricted	1B	Expressed in the dorsolateral portion of the neuroepithelium.

Structure	Level	Pattern	Image	Note
TS17: brain	Present	Regionally restricted	1C	Expression in the dorsal midline extended rostoral to the border between the diencephalon and telencephalon.
TS17: brain ventricle	Present	Regionally restricted	1C	Expressed in the medial portions of the telencephalic ventricles.

Structure	Level	Pattern	Image	Note
TS17: neural tube	Present	Regionally restricted	1D	Expressed in the dorsal portion extending along the anteroposterior axis to the mesencephalon.
TS17: hindbrain	Present	Regionally restricted	1D	Expressed in the dorsolateral portion of the neuroepithelium.

Structure	Level	Pattern	Image	Note
TS20: spinal cord	Absent		1E
TS20: forelimb interdigital region mesenchyme	Present		1E

Structure	Level	Pattern	Image	Note
TS19: future spinal cord	Present	Regionally restricted	2A	Expressed in the dorsal region.
TS19: neural tube ventricular layer	Present	Regionally restricted	2A	Expressed in the dorsal half of the neuroepithelium along the entire spinal cord.
TS19: dorsal root ganglion	Absent		2A

Structure	Level	Pattern	Image	Note
TS19: head mesenchyme	Present	Regionally restricted	2C	Expressed in the dorsal region.
TS19: metencephalon	Present	Regionally restricted	2C	Expressed in the dorsal midline. The border of the positive and negative areas coincided with the presumptive sulcus limitaus.

Structure	Level	Pattern	Image	Note
TS19: metencephalon ventricular layer	Present		2D

Structure	Level	Pattern	Image	Note
TS19: metencephalon ventricular layer	Absent		3A
TS19: head mesenchyme	Present	Regionally restricted	3A	Expressed in the cells adjacent to the open neuroectoderm.

Structure	Level	Pattern	Image	Note
TS19: future spinal cord	Present		3B	Significantly reduced expression.

Structure	Level	Pattern	Image	Note
TS19: future spinal cord	Present	Regionally restricted	3C	Barely detected in the caudal spina bifida region.

Structure	Level	Pattern	Image	Note
TS19: neural tube	Weak		4a upper	Did not become detectable until 7h of reaction; by 17h still barely above the detection limit.
TS19: mesenchyme derived from lateral plate	Present		4a upper

Structure	Level	Pattern	Image	Note
TS19: neural tube	Present		4a lower	Detectable within 4h of reaction; by 17h obvious expression was shown.
TS19: mesenchyme derived from lateral plate	Present		4a lower

Structure	Level	Pattern	Image	Note
TS19: diencephalon	Present	Regionally restricted		Expressed in the dorsal midline.
TS19: midbrain	Present	Regionally restricted		Expressed in the dorsal midline.

Structure	Level	Pattern	Image	Note
TS20: telencephalon	Present

Structure	Level	Pattern	Image	Note
TS19: metencephalon	Present	Regionally restricted		Expressed in the most dorsolateral portion of the open metencephalon, where neuroepithelial cells were adjacent to the skin ectoderm.