Probe:	MB18
Probe preparation:	Antisense labelled with P33 RNA
Visualized with:	Autoradiography

Structure	Level	Pattern	Image	Note
TS13: embryo	Absent		1B

Structure	Level	Pattern	Image	Note
TS15: future hindbrain	Present	Regionally restricted	1E	Expression is punctate and is localized to the outermost cell layer of the early hindbrain.
TS15: future forebrain	Absent		1E
TS15: future midbrain	Absent		1E
TS15: future spinal cord	Absent		1E
TS15: notochord	Absent		1E
TS15: peripheral nervous system	Absent		1E
TS15: central nervous system	Present		1E	No expression was deteted in tissues lying outside the developing central nervous system, nor was it present in the floor plate and neural crest.

Structure	Level	Pattern	Image	Note
TS19: brain	Strong	Regionally restricted	1H	There is nearly ubiquitous expression in postmitotic neurons within the early central nervous system.
TS19: future spinal cord	Strong	Regionally restricted	1H	There is strong expression in both the thoracic and tail region of the neural tube. This expression is predominantly in the dorsal regions of the neural tube where the cell bodies of interneurons and commissural neurons reside.
TS19: central nervous system	Present		1H	No expression was deteted in tissues lying outside the developing central nervous system, nor was it present in the floor plate and neural crest.
TS19: notochord	Absent		1H
TS19: peripheral nervous system	Absent		1H

Structure	Level	Pattern	Image	Note
TS21: central nervous system	Present	Regionally restricted	2B	There is nearly ubiquitous expression in postmitotic neurons within the early central nervous system.
TS21: hypothalamus	Strong		2B
TS21: thalamus	Strong		2B
TS21: telencephalon	Strong	Regionally restricted	2B	There is strong expression in the hippocampus primordium.
TS21: midbrain mantle layer	Present		2B	Expression is present in the roof.
TS21: hindbrain	Present	Regionally restricted	2B	Expression is present in the mantle layer throughout the hindbrain.
TS21: primitive bladder	Weak		2B	There is weak expression in the early bladder.

Structure	Level	Pattern	Image	Note
TS21: cerebral cortex	Strong	Regionally restricted	3E , 3B	There is strong expression in the preplate. Expression is most intense in those neurons residing at the inner and outer edge, while the centrally placed neurons express at significantly lower levels.

Structure	Level	Pattern	Image	Note
TS25: cerebral cortex	Present	Regionally restricted	4B	Thre is high expression in the cranial aspect of the cortex; expression is predominantly in the cortical layers above the intermediate zone.
TS25: olfactory lobe	Strong		4B	Expression is present in the olfactory bulb.
TS25: hippocampus	Strong		4B
TS25: hindbrain	Weak	Uniform	4B	Expression is ubiquitous.
TS25: midbrain	Weak	Uniform	4B	Expression is ubiquitous.
TS25: cerebellum	Strong	Regionally restricted	4B	Expression is present in the external granular layer.

Structure	Level	Pattern	Image	Note
TS26: brain	Present		4E	Expression has been extinguished in most brain regions by this age.
TS26: cerebral cortex	Absent		4E
TS26: midbrain	Present	Regionally restricted	4E	Expression is restricted to several structures, including the substantial nigra, the zona aserta, and the red cell nucleus.
TS26: cerebellum	Present	Regionally restricted	4E	Expression is present in the external granular layer.
TS26: hippocampus	Present		4E

Structure	Level	Pattern	Image	Note
TS26: cerebellum	Strong	Regionally restricted	4H	Expression is present in the external granular layer.

Structure	Level	Pattern	Image	Note
TS26: olfactory lobe	Strong	Regionally restricted	5B	Expression is restricted to the presumptive granular cell layer within the olfactory bulb.

Structure	Level	Pattern	Image	Note
TS26: olfactory lobe	Strong	Regionally restricted	5E	Expression is restricted to the presumptive granular cell layer within the olfactory bulb.

Structure	Level	Pattern	Image	Note
TS26: cerebral cortex	Absent		5H	Expression is absent from all cortical layers.
TS26: hypothalamus	Present		5H
TS26: thalamus	Absent		5H

Structure	Level	Pattern	Image	Note
TS26: hippocampus	Strong		5K	There is strong expression in the CA1, CA2, CA3, and CA4 regions of the hippocampus.

Structure	Level	Pattern	Image	Note
TS19: telencephalon	Strong	Regionally restricted	6B	Expression is present in postmitotic cells, thus representing the early preplate of the developing cortex. There is no expression in the external pial layer.
TS19: telencephalon ventricular layer	Absent		6B

Structure	Level	Pattern	Image	Note
TS19: telencephalon	Strong	Regionally restricted	6D	Expression is present in the early postmitotic neurons of the lateral eminence.

Structure	Level	Pattern	Image	Note
TS19: future spinal cord	Strong	Regionally restricted	6F	There is expression in both the thoracic and tail regions of the neural tube. This expression is predominantly in the dorsal regions, where the cell bodies of interneurons and commissural neurons reside. Lower levels were detected in the motor columns.
TS19: neural tube ventricular layer	Absent		6F

Structure	Level	Pattern	Image	Note
TS20: limb mesenchyme	Present	Regionally restricted	7A/B	Expression is present in mesodermal condensations around the cartilage core in the developing limb structures.

Structure	Level	Pattern	Image	Note
TS21: skeletal muscle	Present	Regionally restricted	7C/D	Expression is present in the facial musculature, particularly around the developing palate.
TS21: primary palate	Present		7C/D

Structure	Level	Pattern	Image	Note
TS21: reproductive system	Present	Regionally restricted	7E/F	Expression is present in the urogenital ridge.

Structure	Level	Pattern	Image	Note
TS23: reproductive system	Strong	Regionally restricted	7G/H	There is strong expression at the tip of the genital tubercle within the developing urogenital region.

Structure	Level	Pattern	Image	Note
TS20: skeletal muscle	Present	Regionally restricted		Expression is present in the facial musculature, particularly around the developing palate.

Structure	Level	Pattern	Image	Note
TS22: limb mesenchyme	Absent			There is no expression in mesodermal condensations around the cartilage core in the developing limb structures.

Structure	Level	Pattern	Image	Note
TS23: thalamus	Absent
TS23: hypothalamus	Strong

Structure	Level	Pattern	Image	Note
TS24: superior cervical ganglion	Present			There is no other expression in the peripheral nervous system.
TS24: reproductive system	Strong	Regionally restricted		There is strong expression at the tip of the genital tubercle within the developing urogenital region.
TS24: bladder	Present	Regionally restricted		There are relatively high levels of expression in the mesenchyme lying directly adjacent to the epithelium. There is no expression in the epithelial layer.