Probe:	proalpha1(I) cDNA
Probe preparation:	Antisense labelled with S35 RNA
Visualized with:	Autoradiography

Structure	Level	Pattern	Image	Note
TS13: amnion	Weak		1A/B
TS13: head mesenchyme	Weak	Regionally restricted	1A/B	Expressed in part of the head mesenchyme.

Structure	Level	Pattern	Image	Note
TS17: head mesenchyme	Present	Regionally restricted	1D/E	Expressed in the cranial mesenchyme surrounding the developing brain.
TS17: gut mesenchyme	Present	Regionally restricted	1D/E	Expressed in the mesenchyme surrounding the developing intestine.
TS17: dorsal aorta	Present		1D/E
TS17: limb bud	Present		1D/E
TS17: nasal mesenchyme	Present		1D/E
TS17: pericardium	Present		1D/E

Structure	Level	Pattern	Image	Note
TS20: atrioventricular endocardial cushion	Present		2A
TS20: dermis	Present		2A
TS20: diaphragm	Present		2A
TS20: mandibular process	Present		2A
TS20: maxillary process	Present		2A
TS20: meninges	Present		2A
TS20: nasal mesenchyme	Present		2A
TS20: tail dermatome	Present		2A
TS20: tail sclerotome	Present		2A
TS20: thoracic body wall	Present		2A
TS20: tongue mesenchyme	Present		2A
TS20: intestine	Present		2A	strongest expression
TS20: umbilical cord	Present		2A	strongest expression
TS20: body wall mesenchyme	Present	Regionally restricted	2A	Expressed in mesenchymal tissue surrounding the rostral prevertebrae.
TS20: pericardium	Present		2A	Also expressed in the fibrous connective tissue.

Structure	Level	Pattern	Image	Note
TS22: vibrissa dermal component	Present		3A	weaker expression

Structure	Level	Pattern	Image	Note
TS22: atrioventricular valve	Present		3B
TS22: lung mesenchyme	Present		3B
TS22: pericardium	Present		3B
TS22: trachea mesenchyme	Present		3B
TS22: rib cartilage condensation	Present	Regionally restricted	3B	Expressed in in the periosteum.
TS22: vertebra	Present	Regionally restricted	3B	Expressed in in the periosteum.
TS22: arch of aorta	Present		3B	aortic trunk

Structure	Level	Pattern	Image	Note
TS22: hindlimb digit mesenchyme	Present	Regionally restricted	3C	Expressed in the perichondrium surrounding the digit cartilage.
TS22: hindlimb digit dermis	Present		3C

Structure	Level	Pattern	Image	Note
TS20: atrioventricular endocardial cushion	Strong		6A/B
TS20: endocardial cushion	Strong		6A/B
TS20: pericardium	Strong	Regionally restricted	6A/B	Expressed in the fibrous connective tissue.

Structure	Level	Pattern	Image	Note
TS22: mandible	Present	Regionally restricted	6D/E	Expressed in the osteoblasts of the alveolar bone of the mandible. Highest levels in the body of the mandible.
TS22: dermis	Present		6D/E
TS22: chondrocranium	Present		6D/E	Highest expression.

Structure	Level	Pattern	Image	Note
TS11: embryo ectoderm	Absent
TS11: embryo endoderm	Absent
TS11: embryo mesoderm	Absent

Structure	Level	Pattern	Image	Note
TS13: pericardium	Weak
TS13: somite	Absent

Structure	Level	Pattern	Image	Note
TS15: pericardium	Present			highest levels of expression
TS15: 1st branchial arch	Present
TS15: forelimb bud	Present
TS15: head mesenchyme	Present

Structure	Level	Pattern	Image	Note
TS17: branchial arch	Present
TS17: dermatome	Present
TS17: sclerotome	Present

Structure	Level	Pattern	Image	Note
TS21: diaphragm	Strong
TS21: intestine	Strong
TS21: thoracic body wall	Strong
TS21: umbilical cord	Strong
TS21: craniocervical region muscle	Present	Regionally restricted
TS21: tongue mesenchyme	Present	Regionally restricted

Structure	Level	Pattern	Image	Note
TS25: tibia	Present	Regionally restricted		Expressed in the zone of ossification. Expression was absent from proliferating chondrocytes and hypertrophic chondrocytes.