Probe:	Boc cDNA1
Probe preparation:	Antisense labelled with S35 RNA
Visualized with:	Autoradiography
Assay notes:	A schematic summary of the spatiotemporal expression pattern is shown in Figure 5.

Structure	Level	Pattern	Image	Note
TS15: neural tube	Strong	Regionally restricted	2A	Expression is in the dorsal region.

Structure	Level	Pattern	Image	Note
TS20: diencephalon	Strong	Regionally restricted	2B	Expression is in the dorsal region.
TS20: spinal cord	Strong	Regionally restricted	2B	Expression is in the dorsal region.
TS20: telencephalon	Strong	Regionally restricted	2B	Expression is in the dorsal region.
TS20: head mesenchyme	Very strong		2B
TS20: limb	Very strong		2B
TS20: lung mesenchyme	Present		2B
TS20: pancreas	Present		2B
TS20: cardiac muscle tissue	Absent		2B
TS20: eye	Absent		2B
TS20: liver	Absent		2B

Structure	Level	Pattern	Image	Note
TS21: inner ear epithelium	Present		2C
TS21: inner ear mesenchyme	Present		2C
TS21: lung mesenchyme	Present		2C
TS21: pancreas	Present		2C
TS21: pons	Present		2C
TS21: pre-cartilage condensation	Present		2C
TS21: temporal bone petrous part	Present		2C
TS21: tongue	Present		2C
TS21: trachea mesenchyme	Present		2C
TS21: cerebellum	Strong		2C
TS21: forelimb musculature	Strong		2C
TS21: hindlimb musculature	Strong		2C
TS21: vertebral axis musculature	Strong		2C
TS21: brain	Present	Regionally restricted	2C	Expression is dorsal.
TS21: esophagus	Present	Regionally restricted	2C	Expression is in the muscle layers.
TS21: intestine	Present	Regionally restricted	2C	Expression is in the muscle layers.
TS21: stomach	Present	Regionally restricted	2C	Expression is in the muscle layers.
TS21: reproductive system	Present	Regionally restricted	2C	Expression is in various components, absent in epithelialized structures.
TS21: midbrain	Present	Graded	2C	Expression is strong dorsal and weak ventral.
TS21: medulla oblongata	Strong	Regionally restricted	2C	Expression is dorsal.
TS21: cartilage	Absent		2C
TS21: liver	Absent		2C
TS21: rib cartilage condensation	Absent		2C

Structure	Level	Pattern	Image	Note
TS23: nose	Strong	Regionally restricted	2D	Expression is in the mesenchyme.
TS23: olfactory epithelium	Weak		2D
TS23: carina trachea	Strong		2D
TS23: cerebellum	Strong		2D
TS23: lung mesenchyme	Strong		2D
TS23: skeletal muscle	Strong		2D
TS23: trachea epithelium	Strong		2D
TS23: trachea mesenchyme	Strong		2D
TS23: trachea vascular element	Strong		2D
TS23: early nephron	Absent		2D
TS23: liver	Absent		2D
TS23: maturing glomerular tuft	Absent		2D
TS23: trachea cartilaginous ring	Absent		2D
TS23: brain ventricular layer	Strong	Regionally restricted	2D	Expression is in the dorsal ventricular zone.
TS23: medulla oblongata	Strong	Regionally restricted	2D	Expression is dorsal.
TS23: midbrain	Present	Graded	2D	Expression is strong dorsal and weak ventral.
TS23: adrenal cortex	Present		2D
TS23: adrenal gland	Present		2D
TS23: dermis	Present		2D
TS23: pancreas	Present		2D
TS23: pons	Present		2D
TS23: tongue	Present		2D
TS23: vibrissa	Present		2D
TS23: esophagus	Present	Regionally restricted	2D	Expression is in the smooth muscle layer.
TS23: intestine	Present	Regionally restricted	2D	Expression is in the smooth muscle layer.
TS23: stomach	Present	Regionally restricted	2D	Expression is in the smooth muscle layer.
TS23: mesenchyme of metanephros	Strong		2D
TS23: renal capsule	Strong		2D
TS23: renal cortex	Strong		2D
TS23: cartilage	Present	Regionally restricted	2D	Expression is in less differentiated cartilage and pre-cartilage.
TS23: embryo mesenchyme	Present		2D

Structure	Level	Pattern	Image	Note
TS25: cerebellum	Strong		2E
TS25: mesenchyme of metanephros	Strong		2E
TS25: renal capsule	Strong		2E
TS25: rib	Strong		2E
TS25: skeletal muscle	Strong		2E
TS25: testis	Strong		2E
TS25: vertebra	Strong		2E
TS25: vibrissa	Strong		2E
TS25: medulla oblongata	Strong	Regionally restricted	2E	Expression is dorsal.
TS25: nose	Present	Regionally restricted	2E	Expression is in the mesenchyme.
TS25: adrenal gland	Present		2E
TS25: dermis	Present		2E
TS25: lung mesenchyme	Present		2E
TS25: pons	Present		2E
TS25: tongue	Present		2E
TS25: trachea mesenchyme	Present		2E
TS25: olfactory epithelium	Weak		2E
TS25: esophagus	Present	Regionally restricted	2E	Expression is in the muscle layers.
TS25: intestine	Present	Regionally restricted	2E	Expression is in the muscle layers.
TS25: stomach	Present	Regionally restricted	2E	Expression is in the muscle layers.
TS25: reproductive system	Present	Regionally restricted	2E	Expression is in various components, absent in epithelialized structures.
TS25: embryo mesenchyme	Present		2E
TS25: cartilage	Present	Regionally restricted	2E	Expression is in less differentiated cartilage and pre-cartilage.
TS25: forebrain	Present	Regionally restricted	2E	Expression is dorsal.
TS25: hindbrain	Present	Regionally restricted	2E	Expression is dorsal.
TS25: midbrain	Present	Graded	2E	Expression is strong dorsal and weak ventral.
TS25: early nephron	Absent		2E
TS25: glomerular tuft	Absent		2E
TS25: liver	Absent		2E
TS25: spleen	Absent		2E

Structure	Level	Pattern	Image	Note
TS17: neural tube	Strong	Regionally restricted	3A/B	Expression is dorsal.
TS17: gonad primordium	Strong		3A/B
TS17: nephrogenic cord	Strong		3A/B
TS17: trunk dermomyotome	Strong		3A/B
TS17: limb mesenchyme	Present	Regionally restricted	3A/B	Expression is in the proximal-anterior region, absent in the most differentiated cartilaginous condensations.
TS17: trunk mesenchyme	Present	Regionally restricted	3A/B	Expression is in the intermediate mesoderm.
TS17: gut	Present	Regionally restricted	3A/B	Expression is in the mesenchyme.
TS17: trunk sclerotome	Absent		3A/B

Structure	Level	Pattern	Image	Note
TS17: neural tube	Strong	Regionally restricted	3C/D	Expression is dorsal.
TS17: trunk dermomyotome	Strong		3C/D
TS17: limb mesenchyme	Present	Regionally restricted	3C/D	Expression is in the proximal-anterior region.
TS17: trunk sclerotome	Absent		3C/D

Structure	Level	Pattern	Image	Note
TS20: limb mesenchyme	Very strong		3E	Expression is in muscle masses, absent in cartilage.

Structure	Level	Pattern	Image	Note
TS23: limb mesenchyme	Strong		3F	Expression is in muscle masses, absent in cartilage.
TS23: dermis	Present		3F

Structure	Level	Pattern	Image	Note
TS22: skeleton	Strong	Regionally restricted	3G	Expression is surrounding the long bones.
TS22: dermis	Present		3G
TS22: limb musculature	Present		3G

Structure	Level	Pattern	Image	Note
TS24: elbow joint	Strong		3H
TS24: knee joint	Strong		3H
TS24: mesenchyme of metanephros	Strong		3H
TS24: renal capsule	Strong		3H
TS24: dermis	Present		3H
TS24: limb musculature	Present		3H
TS24: gut	Present	Regionally restricted	3H	Expression is in the mesentery.
TS24: early nephron	Absent		3H
TS24: liver	Absent		3H
TS24: maturing glomerular tuft	Absent		3H

Structure	Level	Pattern	Image	Note
TS19: diencephalon	Strong	Regionally restricted	4A	Expression is dorsal.
TS19: hindbrain	Strong	Regionally restricted	4A	Expression is dorsal.
TS19: telencephalon	Strong	Regionally restricted	4A	Expression is dorsal.
TS19: midbrain	Strong	Graded	4A	Expression is strong dorsal and weak ventral.

Structure	Level	Pattern	Image	Note
TS20: diencephalon	Strong	Regionally restricted	4B	Expression is dorsal.
TS20: hindbrain	Strong	Regionally restricted	4B	Expression is dorsal.
TS20: telencephalon	Strong	Regionally restricted	4B	Expression is dorsal.
TS20: midbrain	Strong	Graded	4B	Expression is strong dorsal and weak ventral.
TS20: cerebellum primordium	Strong		4B
TS20: pons	Strong		4B
TS20: medulla oblongata	Strong	Regionally restricted	4B	Expression is dorsal.

Structure	Level	Pattern	Image	Note
TS20: diencephalon	Strong	Regionally restricted	4C	Expression is dorsal.
TS20: hindbrain	Strong	Regionally restricted	4C	Expression is dorsal.
TS20: midbrain	Strong	Regionally restricted	4C	Expression is dorsal.
TS20: head mesenchyme	Strong		4C
TS20: telencephalon	Strong	Regionally restricted	4C	Strong dorsal expression.
TS20: ganglionic eminence	Weak		4C
TS20: hypothalamus	Weak		4C
TS20: retina	Absent		4C

Structure	Level	Pattern	Image	Note
TS21: diencephalon	Strong	Regionally restricted	4D	Expression is dorsal.
TS21: hindbrain	Strong	Regionally restricted	4D	Expression is dorsal.
TS21: midbrain	Strong	Regionally restricted	4D	Expression is dorsal.
TS21: head mesenchyme	Strong		4D
TS21: olfactory lobe	Strong		4D
TS21: telencephalon	Strong	Regionally restricted	4D	Strong dorsal expression.
TS21: ganglionic eminence	Weak		4D
TS21: hypothalamus	Weak		4D
TS21: olfactory epithelium	Weak		4D
TS21: retina	Absent		4D

Structure	Level	Pattern	Image	Note
TS21: diencephalon	Strong	Regionally restricted	4E	Expression is dorsal.
TS21: hindbrain	Strong	Regionally restricted	4E	Expression is dorsal.
TS21: telencephalon	Strong	Regionally restricted	4E	Expression is dorsal.
TS21: midbrain	Strong	Graded	4E	Expression is strong dorsal and weak ventral.
TS21: cerebellum	Strong		4E
TS21: head mesenchyme	Strong		4E
TS21: inner ear mesenchyme	Strong		4E
TS21: medulla oblongata	Strong	Regionally restricted	4E	Expression is dorsal.
TS21: pons	Present		4E
TS21: tongue	Present		4E
TS21: hypothalamus	Weak		4E
TS21: inner ear epithelium	Weak		4E
TS21: retina	Absent		4E

Structure	Level	Pattern	Image	Note
TS22: diencephalon	Strong	Regionally restricted	4F	Expression is dorsal.
TS22: hindbrain	Strong	Regionally restricted	4F	Expression is dorsal.
TS22: medulla oblongata	Strong	Regionally restricted	4F	Expression is dorsal.
TS22: telencephalon	Strong	Regionally restricted	4F	Expression is dorsal.
TS22: midbrain	Strong	Graded	4F	Expression is strong dorsal and weak ventral.
TS22: cerebellum	Strong		4F
TS22: head mesenchyme	Strong		4F
TS22: pons	Present		4F
TS22: tongue	Present		4F

Structure	Level	Pattern	Image	Note
TS23: hindbrain	Strong	Regionally restricted	4G	Expression is dorsal.
TS23: midbrain	Strong	Regionally restricted	4G	Expression is dorsal.
TS23: diencephalon	Strong	Regionally restricted	4G	Expression is in the dorsal tip.
TS23: cerebral cortex	Strong	Regionally restricted	4G	Expression is in the dorsal ventricular and subventricular zones, absent in the most differentiated layers.
TS23: tongue	Present		4G

Structure	Level	Pattern	Image	Note
TS23: diencephalon	Strong	Regionally restricted	4H	Expression is dorsal.
TS23: hindbrain	Strong	Regionally restricted	4H	Expression is dorsal.
TS23: medulla oblongata	Strong	Regionally restricted	4H	Expression is dorsal.
TS23: midbrain	Strong	Graded	4H	Expression is strong dorsal and weak ventral.
TS23: cerebral cortex	Strong	Regionally restricted	4H	Expression is in the dorsal ventricular and subventricular zones, absent in the most differentiated layers.
TS23: dermis	Present		4H
TS23: pons	Present		4H
TS23: vibrissa	Present		4H
TS23: cerebellum	Strong		4H

Structure	Level	Pattern	Image	Note
TS24: hindbrain	Present	Regionally restricted	4I	Expression is dorsal.
TS24: medulla oblongata	Present	Regionally restricted	4I	Expression is dorsal.
TS24: midbrain	Present	Graded	4I	Expression is strong dorsal and weak ventral.
TS24: diencephalon	Present	Regionally restricted	4I	Expression is dorsal.
TS24: telencephalon	Present	Regionally restricted	4I	Expression is dorsal.
TS24: rostral migratory stream	Present		4I
TS24: nose	Present	Regionally restricted	4I	Expression is in the mesenchyme.
TS24: cerebellum	Present		4I
TS24: pons	Present		4I
TS24: tongue	Present		4I
TS24: olfactory epithelium	Weak		4I

Structure	Level	Pattern	Image	Note
TS20: spinal cord ventricular layer	Strong	Regionally restricted	4J	Expression is in the dorsal ventricular zone.
TS20: vertebral cartilage condensation	Strong		4J
TS20: vertebral pre-cartilage condensation	Strong		4J

Structure	Level	Pattern	Image	Note
TS22: spinal cord ventricular layer	Strong	Regionally restricted	4K	Expression is in a narrow band of cells.
TS22: skeletal muscle	Present	Regionally restricted	4K	Expression is in muscle masses surrounding the vertebral column.
TS22: trunk mesenchyme	Present	Regionally restricted	4K	Expression is in mesenchyme surrounding the vertebral column.
TS22: mesenchyme of metanephros	Strong		4K
TS22: vertebral cartilage condensation	Strong		4K
TS22: vertebral pre-cartilage condensation	Strong		4K
TS22: dermis	Present		4K
TS22: early nephron	Absent		4K
TS22: maturing glomerular tuft	Absent		4K

Structure	Level	Pattern	Image	Note
TS23: spinal cord ventricular layer	Strong	Regionally restricted	4L	Expression is in a narrow band of cells.
TS23: skeletal muscle	Present	Regionally restricted	4L	Expression is in muscle masses surrounding the vertebral column.
TS23: trunk mesenchyme	Present	Regionally restricted	4L	Expression is in mesenchyme surrounding the vertebral column.
TS23: vertebral cartilage condensation	Strong		4L
TS23: vertebral pre-cartilage condensation	Strong		4L
TS23: dermis	Present		4L