Probe:	ActR-I cDNA1
Probe preparation:	Antisense labelled with S35 RNA
Visualized with:	Autoradiography

Structure	Level	Pattern	Image	Note
TS20: cerebellum primordium	Present	Regionally restricted	4A	Expression is in the junction.
TS20: pons	Present	Regionally restricted	4A	Expression is in the junction.
TS20: cerebral cortex	Present		4A
TS20: hypothalamus	Present		4A
TS20: thalamus	Present		4A
TS20: skin	Present		4A

Structure	Level	Pattern	Image	Note
TS20: endolymphatic sac	Present		4B
TS20: hypothalamus	Present		4B
TS20: neurohypophysis infundibulum	Present		4B
TS20: skin	Present		4B
TS20: thalamus	Present		4B
TS20: vestibulo-cochlear ganglion complex	Strong		4B
TS20: trigeminal ganglion	Weak		4B
TS20: medulla oblongata	Present	Regionally restricted	4B	Expression is in the medullary raphe.
TS20: internal carotid artery	Present	Regionally restricted	4B	Expression is in the carotid arteries and the middle cerebral arteries.
TS20: head mesenchyme	Present	Regionally restricted	4B	Expression is in the condensations that form the outer table of the primitive ectomeninx.
TS20: posterior semicircular canal	Absent		4B

Structure	Level	Pattern	Image	Note
TS20: arterial system	Present		4C
TS20: otic capsule	Present		4C
TS20: outer ear	Present		4C
TS20: tongue	Present		4C
TS20: vibrissa	Present		4C
TS20: skeletal muscle	Present	Regionally restricted	4C	Expression is in the premuscle condensations in the oral region.
TS20: nasal septum mesenchyme	Present	Regionally restricted	4C	Expression is in the precartilage primordium.
TS20: Meckel's cartilage	Absent		4C
TS20: accessory nerve	Absent		4C
TS20: esophagus	Absent		4C
TS20: trachea	Absent		4C
TS20: vagus ganglion	Absent		4C
TS20: venous system	Absent		4C
TS20: vomeronasal organ	Absent		4C
TS20: mandibular process	Absent		4C	Expression is absent in the dental lamina.
TS20: maxillary process	Absent		4C	Expression is absent in the dental lamina.

Structure	Level	Pattern	Image	Note
TS20: arterial system	Present	Regionally restricted	4D	Expression is in the arteries in the thoracic region, including the vitelline artery.
TS20: branchial arch artery	Present		4D
TS20: dorsal aorta	Present		4D
TS20: endocardial cushion	Present		4D
TS20: internal carotid artery	Present		4D
TS20: umbilical artery	Present		4D
TS20: vertebral artery	Present		4D
TS20: skeleton	Present	Regionally restricted	4D	Expression is in the thoracic wall.
TS20: esophagus	Absent		4D
TS20: trachea	Absent		4D
TS20: venous system	Absent		4D

Structure	Level	Pattern	Image	Note
TS20: rib pre-cartilage condensation	Present		5
TS20: shoulder mesenchyme	Present		5
TS20: stomach mesenchyme	Present		5
TS20: tongue mesenchyme	Present		5
TS20: head mesenchyme	Present	Regionally restricted	5	Expression is in the mesenchyme of the snout.
TS20: gonad	Weak		5
TS20: stomach epithelium	Absent		5

Structure	Level	Pattern	Image	Note
TS20: shoulder mesenchyme	Present		6A
TS20: telencephalon	Present		6A
TS20: tongue mesenchyme	Present		6A
TS20: midbrain	Strong	Regionally restricted	6A	Expression is at the bottom.
TS20: head mesenchyme	Present		6A	Expression is in the mesenchyme of the snout.
TS20: medulla oblongata floor plate	Absent		6A
TS20: metencephalon floor plate	Absent		6A
TS20: midbrain roof plate	Absent		6A

Structure	Level	Pattern	Image	Note
TS20: lung mesenchyme	Present		6B
TS20: shoulder mesenchyme	Present		6B
TS20: stomach mesenchyme	Present		6B
TS20: telencephalon	Present		6B
TS20: tongue mesenchyme	Present		6B
TS20: midbrain	Present	Regionally restricted	6B	Expression is at the bottom.
TS20: head mesenchyme	Present	Regionally restricted	6B	Expression is in the mesenchyme of the snout.
TS20: axial skeleton	Present	Regionally restricted	6B	Expression is in the intervertebral disks.
TS20: lung epithelium	Absent		6B
TS20: medulla oblongata floor plate	Absent		6B
TS20: metencephalon floor plate	Absent		6B
TS20: midbrain roof plate	Absent		6B
TS20: stomach epithelium	Absent		6B

Structure	Level	Pattern	Image	Note
TS20: septum transversum	Present
TS20: tail sclerotome	Present
TS20: olfactory epithelium	Absent