Antibody:	anti-CD140a/Pdgfra (APA5)
Detection system:	Secondary antibody coupled to horseradish peroxidase
Assay notes:	Tissue was embedded in polyester wax for sectioning.

Structure	Level	Pattern	Image	Note
TS21: embryo	Present		1B left	Expression is found in many tissues.
TS21: mesenchyme of metanephros	Present		1B left
TS21: ureteral mesenchyme	Present		1B left	Expression is found in mesenchyme surrounding urethric tubules.
TS21: carina trachea mesenchyme	Present		1B left	Expression is found in the regions where tracheal cartilage develops.
TS21: mandible mesenchyme	Present		1B left
TS21: primary palate	Present		1B left	Expression is found in the palate region.

Structure	Level	Pattern	Image	Note
TS21: embryo	Absent		1B right

Structure	Level	Pattern	Image	Note
TS9: ectoplacental cone	Present		2
TS9: extraembryonic visceral endoderm	Present		2
TS9: parietal endoderm	Present		2
TS9: extraembryonic endoderm	Weak		2
TS9: extraembryonic ectoderm	Absent		2

Structure	Level	Pattern	Image	Note
TS10: embryo mesoderm	Present		3A	Expression is in the proximal posterior part of the embryo.
TS10: ectoplacental cone	Present		3A

Structure	Level	Pattern	Image	Note
TS10: embryo mesoderm	Present		3B	Expression is in the proximal posterior part of the embryo.
TS10: ectoplacental cone	Present		3B

Structure	Level	Pattern	Image	Note
TS12: paraxial mesenchyme	Strong		3C
TS12: lateral plate mesoderm	Absent		3C	No significant expression in proximal lateral mesoderm. Expression might be present in a few cells.
TS12: extraembryonic mesenchyme	Absent		3C	Expression might be present in a few cells.
TS12: ectoplacental cone	Present		3C

Structure	Level	Pattern	Image	Note
TS12: paraxial mesenchyme	Strong		3D
TS12: lateral plate mesoderm	Absent		3D	No significant expression in proximal lateral mesoderm. Expression might be present in a few cells.
TS12: extraembryonic mesenchyme	Absent		3D	Expression might be present in a few cells.
TS12: ectoplacental cone	Present		3D
TS12: allantois	Weak		3D

Structure	Level	Pattern	Image	Note
TS12: blood island	Absent

Structure	Level	Pattern	Image	Note
TS13: somite	Present		4A
TS13: head mesenchyme	Present	Diffuse	4A
TS13: future hindbrain neural crest	Present	Regionally restricted	4A	Expression is found in the neural crest cells at pro-rhombomeres A and B.

Structure	Level	Pattern	Image	Note
TS13: somite	Present		4B

Structure	Level	Pattern	Image	Note
TS15: future brain	Present	Regionally restricted	4C	Expression is found along the dorsal midline at the head region.
TS15: somite	Present		4C

Structure	Level	Pattern	Image	Note
TS15: head mesenchyme	Strong		5A	Strong expression in anterior and basal parts of the head, the facial mesenchyme.
TS15: branchial arch	Strong		5A
TS15: somite	Strong	Regionally restricted	5A	Strong expression in posterior somites, as well as the basal part of anterior somites, the intervertebral disc precursors.

Structure	Level	Pattern	Image	Note
TS17: head mesenchyme	Strong		5B	Strong expression in anterior and basal parts of the head, the facial mesenchyme.
TS17: forelimb bud apical ectodermal ridge	Present		5B
TS17: hindlimb bud apical ectodermal ridge	Present		5B
TS17: forelimb bud	Present	Regionally restricted	5B	Expression in the basal part.
TS17: hindlimb bud	Present	Regionally restricted	5B	Expression in the basal part.
TS17: heart	Present		5B
TS17: trunk mesenchyme	Strong	Regionally restricted	5B	Strong expression in splanchic mesenchyme.
TS17: lens pit	Present		5B	Expression in the lens.
TS17: somite	Present		5B

Structure	Level	Pattern	Image	Note
TS20: embryo	Present		6A
TS20: mandible primordium	Present		6A
TS20: primary palate	Present		6A	Expression is seen in the palate region.
TS20: paraxial mesenchyme	Present	Regionally restricted	6B , 6A	Expression in mesenchyme around vertebrae.
TS20: trunk mesenchyme	Present	Regionally restricted	6C , 6A	Expression in mesenchyme surrounding the kidney.
TS20: ureteral mesenchyme	Present		6A , 6C	Expression in mesenchyme surrounding the urethric tubules.
TS20: right atrium valve	Present		6D , 6A	Expression in heart valves.
TS20: pericardium	Present		6D , 6A
TS20: thymus primordium	Present	Regionally restricted	6D , 6A	Expression in mesenchymal cells separating the thymic lobules.
TS20: trachea	Present		6D , 6A
TS20: spinal cord	Weak	Regionally restricted	6A , 6E	Expression in glial precursors.
TS20: optic nerve	Present	Regionally restricted	6A , 6F	Expression is concentrated in the dorsal part of the eye, emanating downwards along the presumptive optic nerve; the expression pattern suggests the expressing cells are glial precursors.

Structure	Level	Pattern	Image	Note
TS20: paraxial mesenchyme	Present	Regionally restricted	7A	Expresssion in the mesenchymal cells in the intervertebral discs.

Structure	Level	Pattern	Image	Note
TS20: trunk mesenchyme	Present	Regionally restricted	7B	Expression in mesenchymal cells surrounding the kidney.
TS20: mesenchyme of metanephros	Present		7B

Structure	Level	Pattern	Image	Note
TS20: thymus primordium	Present		7C

Structure	Level	Pattern	Image	Note
TS20: right atrium valve	Present		7D	Expression in heart valve.
TS20: pericardium	Present		7D

Structure	Level	Pattern	Image	Note
TS20: spinal cord	Weak	Regionally restricted	7E	Expression in the glial precursors.

Structure	Level	Pattern	Image	Note
TS20: optic nerve	Present	Regionally restricted	7F	Expression is concentrated in the dorsal part of the eye, emanating downwards along the presumptive optic nerve; the expression pattern suggests the expressing cells are glial precursors.

Structure	Level	Pattern	Image	Note
TS24: tooth mesenchyme	Strong		8A
TS24: tongue	Weak		8A

Structure	Level	Pattern	Image	Note
TS24: tongue mesenchyme	Weak	Regionally restricted	8B	Expression in strings of mesenchymal cells in the muscular region running vertically between the extrinsic muscle of tongue and cells surrounding Meckel's cartilage.

Structure	Level	Pattern	Image	Note
TS24: bronchus	Strong		8C

Structure	Level	Pattern	Image	Note
TS24: lung mesenchyme	Strong		8D	Expression in mesenchymal cells surrounding the bronchial epithelial cells/developing broncial tree.

Structure	Level	Pattern	Image	Note
TS24: choroid plexus	Present		8E

Structure	Level	Pattern	Image	Note
TS24: choroid plexus	Strong		8F	Strong expression in epithelial surface of choroid plexus.