Probe:	Etl2 cDNA2
Probe preparation:	Antisense labelled with S35 RNA
Visualized with:	Autoradiography
Assay notes:	Sections were fixed with 4% paraformaldehyde.

Structure	Level	Pattern	Image	Note
TS13: yolk sac	Present
TS13: embryo	Absent
TS28: decidua	Present	Regionally restricted		Expression was confined to the antimesometrial region.

Structure	Level	Pattern	Image	Note
TS17: embryo mesenchyme	Weak	Widespread
TS17: central nervous system	Present			Expression was in the neural tube.
TS17: fronto-nasal process mesenchyme	Present

Structure	Level	Pattern	Image	Note
TS20: central nervous system	Weak		6A/D
TS20: liver	Weak		6A/D
TS20: embryo mesenchyme	Present	Widespread	6A/D
TS20: trunk mesenchyme	Strong	Regionally restricted	6A/D	A stronger signal is seen in the cells surrounding the prevertebrae.
TS20: head mesenchyme	Strong	Regionally restricted	6A/D	Stronger expression was detected in the craniofacial mesenchyme, in particular in cells surounding the developing nasal capsule.
TS20: bronchus	Present		6A/D
TS20: heart	Present		6A/D
TS20: intraembryonic coelom	Present	Regionally restricted	6A/D	Expression was detected in the diaphragm.

Structure	Level	Pattern	Image	Note
TS23: ventricular layer	Weak		6B/E
TS23: embryo mesenchyme	Weak	Widespread	6B/E	Expression was weak in mesenchymal cells throughout the embryo.
TS23: cartilage	Strong	Regionally restricted	6B/E	Strong expression was found in all perichondral cells.
TS23: skeleton	Strong	Regionally restricted	6B/E	Strong expression was detected in periosteal cells.
TS23: lower jaw incisor	Present		6B/E
TS23: spinal ganglion	Present		6B/E
TS23: tongue mesenchyme	Present		6B/E
TS23: vibrissa follicle	Present		6B/E
TS23: aorta	Present	Regionally restricted	6B/E	Expression was detected in the walls of the aortic trunk.
TS23: skin	Present	Regionally restricted	6B/E	Expression was detected in the mesenchyme.

Structure	Level	Pattern	Image	Note
TS26: cartilage	Strong	Regionally restricted	6C/F	Expression was strong in perichondral cells.
TS26: skeleton	Strong	Regionally restricted	6C/F	Expression was strong in periosteal cells.
TS26: incisor dental papilla	Strong		6C/F
TS26: vibrissa follicle	Strong	Regionally restricted	6C/F	Expression was detected in the dermal sheath and external root sheath of whisker follicles.
TS26: diencephalon ventricular layer	Weak	Regionally restricted	6C/F	Weak expression was detected in the ventricular layer of the third ventricle.

Structure	Level	Pattern	Image	Note
TS23: incisor dental papilla	Strong	Non-Uniform	7A/C	Expression was strong in the dental papilla, in particular in the cuspal region.
TS23: incisor	Strong	Regionally restricted	7A/C	Expression was strong in the dental papilla but absent from the odontoblast layer.
TS23: dental sac	Present		7A/C

Structure	Level	Pattern	Image	Note
TS26: incisor dental papilla	Strong	Regionally restricted	7B/D	Expression was confined to cells underlying the odontoblast layer and at the tooth base.
TS26: dental sac	Present		7B/D

Structure	Level	Pattern	Image	Note
TS23: dermis	Strong	Regionally restricted	7E/G	Expression was restricted to the papillary layer of the dermis.
TS23: vibrissa dermal component	Strong		7E/G

Structure	Level	Pattern	Image	Note
TS26: epidermis	Strong		7F/H
TS26: vibrissa dermal component	Strong		7F/H
TS26: vibrissa follicle	Strong	Regionally restricted	7F/H	Expression was detected in the external root sheath.
TS26: epidermis granular layer	Present	Regionally restricted	7F/H	Expression in the external root sheath extended into the granular layer of the epidermis.

Structure	Level	Pattern	Image	Note
TS23: ilium	Strong	Regionally restricted	8A/B	Expression was strong in cells of the periost but absent in the region of endochondral ossification.

Structure	Level	Pattern	Image	Note
TS23: cartilage	Present	Regionally restricted		Expression was confined to the perichondrium.