Probe:	P4.2 cDNA1
Probe preparation:	Antisense labelled with P33 RNA
Visualized with:	Autoradiography
Assay notes:	Each pair of image panes represents a bright-field image pane and a dark-field image pane.

Structure	Level	Pattern	Image	Note
TS9: embryo	Absent

Structure	Level	Pattern	Image	Note
TS12: blood vessel	Weak		2A , 2B	Expression was detected in erythroid cells in the early heart region and blood vessels.
TS12: heart	Weak		2A , 2B	Expression was detected in erythroid cells in the early heart region and blood vessels.

Structure	Level	Pattern	Image	Note
TS12: blood island	Present		2D , 2C	Expression was detected in the blood islands of the visceral yolk sac.

Structure	Level	Pattern	Image	Note
TS17: blood vessel	Present		3A , 3B
TS17: heart	Present		3A , 3B
TS17: brain	Absent		3B , 3A

Structure	Level	Pattern	Image	Note
TS17: heart	Present	Regionally restricted	3D , 3C	Expression was detected in the circulating erythroid cells but was not seen in cardiomyocytes.

Structure	Level	Pattern	Image	Note
TS17: liver	Weak	Regionally restricted	3F , 3E	Expression was detected in the erythroid cells in the sinusoids and vessels of the liver.

Structure	Level	Pattern	Image	Note
TS20: blood vessel	Present		4A , 4B
TS20: heart	Present		4A , 4B
TS20: liver	Present		4A , 4B

Structure	Level	Pattern	Image	Note
TS20: heart	Present	Regionally restricted	4C , 4D	Expression was detected only in erythroid cells inside the heart chambers.

Structure	Level	Pattern	Image	Note
TS20: dorsal aorta	Present	Regionally restricted	4E , 4F	Expression was detected in circulating erythroid cells in blood vessels.

Structure	Level	Pattern	Image	Note
TS20: liver	Present		5B , 5A	Expression was greatly enhanced in the liver at E12.5 compared to E10.5.

Structure	Level	Pattern	Image	Note
TS22: liver	Strong		5C , 5D	Expression signal in the liver was the strongest among all organs.
TS22: blood vessel	Weak		5D , 5C
TS22: heart	Weak		5D , 5C
TS22: thymus primordium	Absent		5D , 5C

Structure	Level	Pattern	Image	Note
TS28: thymus	Absent

Structure	Level	Pattern	Image	Note
TS24: liver	Strong	Regionally restricted	5F , 5E	Expression was strong in erythroid cells of the hepatic mesoderm.
TS24: blood vessel	Weak		5F , 5E
TS24: heart	Weak		5F , 5E
TS24: metanephros	Trace		5E , 5F	Little or no specific labeling was seen in metanephros.

Structure	Level	Pattern	Image	Note
TS28: liver	Trace		5H , 5G	Expression signal was almost undetectable in the liver after birth.

Structure	Level	Pattern	Image	Note
TS27: spleen red pulp	Present

Structure	Level	Pattern	Image	Note
TS28: spleen red pulp	Present		6B , 6A
TS28: spleen white pulp	Absent		6B , 6A

Structure	Level	Pattern	Image	Note
TS28: spleen red pulp	Present		6C , 6D	Expression was detected in erythroid cells of red pulp from spleen. Higher intensity was detected in areas with more mature erythroid cells. Signal was not detected in megakaryocytes.

Structure	Level	Pattern	Image	Note
TS28: bone marrow	Present		6E , 6F	Expression was detected in erythroid cells and colonies in the bone marrow. No signal was detected in cells of nonerythroid lineage, including megakaryocytes.