Probe:	Id3 cDNA3
Probe preparation:	Antisense labelled with S35 RNA
Visualized with:	Autoradiography

Structure	Level	Pattern	Image	Note
TS15: central nervous system	Present	Regionally restricted	1A	Expression around the neural canal.
TS15: olfactory placode	Present		1A

Structure	Level	Pattern	Image	Note
TS17: neural tube	Present	Regionally restricted	1B	Expression in ventral and dorsal parts of neural tube.
TS17: branchial arch	Present		1B

Structure	Level	Pattern	Image	Note
TS19: neural tube	Present	Regionally restricted	1C	Expression in ventral and dorsal parts of neural tube.
TS19: Rathke's pouch	Present		1C	Expression in pars intermedia of pituitary gland.

Structure	Level	Pattern	Image	Note
TS20: fronto-nasal process	Present		1D
TS20: pharynx	Present	Regionally restricted	1D	Expression in region between trachea and esophagus.
TS20: adenohypophysis pars intermedia	Present		1D

Structure	Level	Pattern	Image	Note
TS21: spinal cord	Present	Regionally restricted	1F	Expression around the neural canal.
TS21: face	Present	Regionally restricted	1F	Expression in frontonasal processes.
TS21: pharynx	Present	Regionally restricted	1F	Expression in region between trachea and esophagus.
TS21: olfactory epithelium	Present		1F
TS21: adenohypophysis pars intermedia	Present		1F
TS21: metanephros	Present		1F

Structure	Level	Pattern	Image	Note
TS22: spinal cord	Present	Regionally restricted	1G	Expression around the neural canal.
TS22: olfactory epithelium	Present		1G
TS22: genital tubercle	Present	Regionally restricted	1G	Expression in distal part of genital eminence.

Structure	Level	Pattern	Image	Note
TS23: olfactory epithelium	Present		1H
TS23: perichondrium	Present	Regionally restricted	1H	Expression in perichondrial cells around the vertebral processes.
TS23: metanephros	Present		1H
TS23: tooth	Present		1H

Structure	Level	Pattern	Image	Note
TS27: brain	Absent
TS27: metanephros	Present

Structure	Level	Pattern	Image	Note
TS25: metanephros	Present

Structure	Level	Pattern	Image	Note
TS21: telencephalon	Present	Regionally restricted	2A/B	Expression locally restricted hippocampal region of forebrain.

Structure	Level	Pattern	Image	Note
TS21: midbrain floor plate	Present		2C/D	Expression restricted to ventral part (floor) of midbrain.

Structure	Level	Pattern	Image	Note
TS21: medulla oblongata	Present	Regionally restricted	2E/F	Expression in specific areas of anterior and posterior hindbrain -- metencephalic and myelencephalic regions close to choroid plexus.
TS21: metencephalon	Present	Regionally restricted	2E/F	Expression in specific areas of anterior and posterior hindbrain -- metencephalic and myelencephalic regions close to choroid plexus.

Structure	Level	Pattern	Image	Note
TS21: adenohypophysis pars intermedia	Present		2G/H

Structure	Level	Pattern	Image	Note
TS21: lower jaw tooth epithelium	Present	Regionally restricted	3A/B/C	Expression in mandible restricted to enamel organ at bud stage of tooth development.

Structure	Level	Pattern	Image	Note
TS23: enamel organ	Present			Expression in enamel organ of tooth at cap stage of tooth development.

Structure	Level	Pattern	Image	Note
TS27: molar enamel organ	Present	Regionally restricted	3D/E	Expression in ameloblast layer of bell-shaped molar.
TS27: molar dental pulp	Present	Regionally restricted	3D/E	Expression also in the odontoblast layer.

Structure	Level	Pattern	Image	Note
TS21: collecting duct	Present		4A/B	Expression in newly forming ureteric collecting duct system, built up from proliferating elongating collecting tubules in inner part of kidney.
TS21: renal cortex	Absent		4A/B	No expression in cortical mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS22: urethra	Strong		4C/D

Structure	Level	Pattern	Image	Note
TS19: sclerotome	Present		5A/B

Structure	Level	Pattern	Image	Note
TS20: sclerotome	Present	Regionally restricted		present / RR Expression confined to rostral, less dense part of sclerotome, which will give rise to vertebral body and processes.

Structure	Level	Pattern	Image	Note
TS21: vertebral cartilage condensation	Present	Regionally restricted	5C/D	In cervical region, expression in vertebral processes.

Structure	Level	Pattern	Image	Note
TS21: vertebral cartilage condensation	Present	Regionally restricted		In cervical and thoracic regions, expression in cartilage of vertebral body and vertebral processes.

Structure	Level	Pattern	Image	Note
TS21: sclerotome	Present		5E/F	In lumbar region, expression in sclerotome.
TS21: myotome	Absent		5E/F

Structure	Level	Pattern	Image	Note
TS21: sclerotome	Present	Regionally restricted	5G/H	At posterior end of embryo, expression confined to rostral part of sclerotome.

Structure	Level	Pattern	Image	Note
TS22: perichondrium	Present	Regionally restricted	5I/J	In thoracic region, expression shifted to perichondrial cells around vertebral processes.

Structure	Level	Pattern	Image	Note
TS21: gut	Present	Regionally restricted	6A	Authors report expression in outer lining of gut.

Structure	Level	Pattern	Image	Note
TS21: lung mesenchyme	Present		6D

Structure	Level	Pattern	Image	Note
TS21: endocardial cushion	Present		6G