Probe:	Arf6 cDNA2
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS21: stomach epithelium	Strong		3A
TS21: stomach mesenchyme	Present		3A

Structure	Level	Pattern	Image	Note
TS21: stomach	Absent		3B

Structure	Level	Pattern	Image	Note
TS23: stomach epithelium	Strong		3C
TS23: stomach mesenchyme	Absent		3C

Structure	Level	Pattern	Image	Note
TS27: stomach epithelium	Strong	Regionally restricted	3E	Expressed in the second epithelial cell layer, but not in the surface keratinized layer.
TS27: stomach proventricular region	Strong	Regionally restricted	3E	Expressed in the second epithelial cell layer, but not in the surface keratinized layer.

Structure	Level	Pattern	Image	Note
TS27: body of stomach	Strong	Regionally restricted	3G	Expressed at the surface of the epithelium and the gastric pits.
TS27: stomach epithelium	Strong	Regionally restricted	3G	Expressed at the surface of the epithelium and the gastric pits.

Structure	Level	Pattern	Image	Note
TS28: stomach epithelium	Strong	Regionally restricted	3I	Expressed in the second epithelial cell layer, but not in the surface keratinized layer.
TS28: stomach proventricular region	Strong	Regionally restricted	3I	Expressed in the second epithelial cell layer, but not in the surface keratinized layer.

Structure	Level	Pattern	Image	Note
TS28: body of stomach	Strong	Regionally restricted	3K	Expressed at the surface of the epithelium and the gastric pits. The signal at the neck region of the pits was higher than that at the bottom region,
TS28: stomach epithelium	Strong	Regionally restricted	3K	Expressed at the surface of the epithelium and the gastric pits. The signal at the neck region of the pits was higher than that at the bottom region,

Structure	Level	Pattern	Image	Note
TS21: intestine epithelium	Strong	Regionally restricted	4A	Small intestine.
TS21: intestine mesenchyme	Present	Regionally restricted	4A	Small intestine.
TS21: intestine muscularis	Absent		4A	Small intestine.

Structure	Level	Pattern	Image	Note
TS21: intestine	Absent		4B

Structure	Level	Pattern	Image	Note
TS23: intestine epithelium	Strong	Regionally restricted	4C	Small intestine.
TS23: intestine mesenchyme	Absent		4C	Small intestine.
TS23: intestine muscularis	Absent		4C	Small intestine.

Structure	Level	Pattern	Image	Note
TS27: small intestine epithelium	Strong		4E
TS27: small intestine crypt of lieberkuhn	Present		4E
TS27: small intestine muscularis mucosa	Absent		4E

Structure	Level	Pattern	Image	Note
TS28: small intestine crypt of lieberkuhn	Strong		4G
TS28: small intestine epithelium	Present		4G
TS28: small intestine muscularis mucosa	Absent		4G

Structure	Level	Pattern	Image	Note
TS28: small intestine crypt of lieberkuhn	Present	Regionally restricted	4I	Expressed in enterocytes at the surface, but not in the goblet cells and Paneth cells.
TS28: small intestine muscularis mucosa	Absent		4I

Structure	Level	Pattern	Image	Note
TS23: aorta	Present	Regionally restricted	5B	Expressed in the tunica media.

Structure	Level	Pattern	Image	Note
TS23: right ventricle endocardial lining	Absent		5D

Structure	Level	Pattern	Image	Note
TS23: atrium cardiac muscle	Present		5F	Expressed in the developing myocardial cells in the trabecular and compact myocardium.
TS23: ventricle cardiac muscle	Present		5F	Expressed in the developing myocardial cells in the trabecular and compact myocardium.
TS23: visceral pericardium	Absent		5F	No expression in the mesothelium in epicardium.

Structure	Level	Pattern	Image	Note
TS27: ventricle cardiac muscle	Present		5I
TS27: visceral serosal pericardium	Absent		5I	No expression in the mesothelium in epicardium.

Structure	Level	Pattern	Image	Note
TS28: heart	Absent		5L
TS28: visceral serosal pericardium	Absent		5L	No expression in the mesothelium in epicardium.

Structure	Level	Pattern	Image	Note
TS21: pancreas	Strong	Regionally restricted	6A	Expressed in the islet-like clumps of cells, which differentiate into the exocrine epithelial cells in acini or into the endocrine cells in the islets of Langerhans. Also expressed in the mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS21: pancreas	Absent		6B

Structure	Level	Pattern	Image	Note
TS23: pancreas	Strong	Regionally restricted	6C	Expressed in the islet-like clumps of cells, which differentiate into the exocrine epithelial cells in acini or into the endocrine cells in the islets of Langerhans. But not expressed in the mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS27: pancreatic acinus	Present		6E	Expression present in acinar cells.
TS27: exocrine pancreas	Present		6E
TS27: endocrine pancreas	Present		6E	Much lower expression lelvel.
TS27: islets of Langerhans	Present		6E	Much lower expression lelvel.

Structure	Level	Pattern	Image	Note
TS28: pancreatic acinus	Present		6G	Expression present in acinar cells.
TS28: exocrine pancreas	Present		6G
TS28: endocrine pancreas	Trace		6G	Very low expression in the islets of Langerhans.
TS28: islets of Langerhans	Trace		6G	Very low expression in the islets of Langerhans.

Structure	Level	Pattern	Image	Note
TS21: lung epithelium	Strong		7A	Expressed in the surface epithelium of airway tubules. Expression was higher in bud epithelial cells.
TS21: lung mesenchyme	Present		7A	Expression was lower in surrounding mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS21: lung	Absent		7B

Structure	Level	Pattern	Image	Note
TS23: lung epithelium	Strong	Regionally restricted	7C	Expressed in the surface epithelium of airway tubules. Expression was higher in bud epithelial cells.
TS23: lung mesenchyme	Present		7C	Expression was lower in surrounding mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS27: bronchus epithelium	Present		7E	Expressed in the surface epithelium of airway tubules.
TS27: lung	Present	Regionally restricted	7E	Expressed in epithelial cells, but not in mesenchymal cells.
TS27: alveolus epithelium	Weak		7E

Structure	Level	Pattern	Image	Note
TS28: bronchus epithelium	Present		7G
TS28: alveolus epithelium	Weak		7G
TS28: lung	Present	Regionally restricted	7G	Expressed in epithelial cells, but not in mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS28: bronchiole epithelium	Strong		7I
TS28: alveolus epithelium	Weak		7I
TS28: lung	Present	Regionally restricted	7I	Expressed in epithelial cells, but not in mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS19: liver	Strong		8A , 8B	Expressed in most of the immature hepatoblasts.

Structure	Level	Pattern	Image	Note
TS20: liver	Present		8D , 8E	The positive cell numbers and intensity of expression decreased with development progression.

Structure	Level	Pattern	Image	Note
TS21: liver	Present		8G , 8H	The positive cell numbers and intensity of expression decreased with development progression.

Structure	Level	Pattern	Image	Note
TS23: liver	Present		8K , 8J	The positive cell numbers and intensity of expression decreased with development progression.
TS23: liver vascular element	Absent		8K	Not detected in the endothelial cells of blood vessels.

Structure	Level	Pattern	Image	Note
TS21: renal vesicle	Strong		9A
TS21: mesenchyme of metanephros	Present	Regionally restricted	9A	Expressed in mesenchymal cells surrounding the renal vesicles.

Structure	Level	Pattern	Image	Note
TS21: metanephros	Absent		9B

Structure	Level	Pattern	Image	Note
TS23: renal corpuscle	Strong	Regionally restricted	9E , 9C	Expressed in the epithelial cells.
TS23: renal vesicle	Strong	Regionally restricted	9E , 9C	Expressed in the epithelial cells.
TS23: anlage of loop of Henle of cortical renal tubule	Present		9C , 9E
TS23: comma-shaped body	Present		9C , 9E
TS23: cortical early distal tubule	Present		9C , 9E
TS23: cortical early proximal tubule	Present		9C , 9E
TS23: collecting duct	Weak		9C , 9E

Structure	Level	Pattern	Image	Note
TS27: nephron	Present		9G , 9I
TS27: renal proximal tubule	Present		9G , 9I
TS27: loop of Henle	Weak		9I , 9G
TS27: renal distal tubule	Weak		9I , 9G
TS27: collecting duct	Absent		9G , 9I

Structure	Level	Pattern	Image	Note
TS21: dorsal mesogastrium	Weak	Regionally restricted	10A	Expressed throughout the developing spleen.

Structure	Level	Pattern	Image	Note
TS21: dorsal mesogastrium	Absent		10B

Structure	Level	Pattern	Image	Note
TS23: spleen primordium	Present	Widespread	10C	Expressed in most but not all cells in the spleen.

Structure	Level	Pattern	Image	Note
TS27: spleen	Present	Widespread	10G , 10E	Expressed in most but not all cells in the spleen.
TS27: spleen trabeculum	Weak		10G
TS27: spleen capsule	Absent		10G

Structure	Level	Pattern	Image	Note
TS28: spleen red pulp	Present	Widespread	10I , 10K	Expressed in most cells.
TS28: spleen white pulp	Present	Widespread	10I , 10K	Expressed in most cells.
TS28: spleen capsule	Absent		10I , 10K

Structure	Level	Pattern	Image	Note
TS21: thymus primordium	Strong	Regionally restricted	11A	Expressed in lymphoid (but not all cells) and/or mesenchymal cells. Thymic epithelial cells were also positive. Not expressed in the mesenchymal capsule and capillary endothelium.

Structure	Level	Pattern	Image	Note
TS21: thymus primordium	Absent		11B

Structure	Level	Pattern	Image	Note
TS23: thymus primordium	Strong	Regionally restricted	11C	Expressed in lymphoid (but not all cells) and/or mesenchymal cells. Thymic epithelial cells were also positive. Not expressed in the mesenchymal capsule and capillary endothelium.

Structure	Level	Pattern	Image	Note
TS27: thymus cortex	Present		11G , 11E
TS27: thymus medullary core	Present		11G , 11E
TS27: thymus epithelium	Strong		11G
TS27: thymus thin fibrous capsule	Absent		11G
TS27: thymus	Present	Regionally restricted	11E	Expressed in cortex, medulla and subcapsular epithelium. Not expressed in capsule and trabecular.

Structure	Level	Pattern	Image	Note
TS28: thymus cortex	Present	Clusters	11M , 11I , 11K	Expressed in lymphoid cell clusters.
TS28: thymus medullary core	Present	Clusters	11M , 11I , 11K	Expressed in lymphoid cell clusters.
TS28: thymus epithelium	Strong		11K	Subcapsular epithelium.

Structure	Level	Pattern	Image	Note
TS23: hemolymphoid system	Weak	Regionally restricted	12A	Expressed throughout the developing lymph node.

Structure	Level	Pattern	Image	Note
TS27: lymph node	Present		12C	There are different populations of the cells with a high and low level expression.

Structure	Level	Pattern	Image	Note
TS28: lymph node cortex	Strong	Widespread	12E , 12G	The germinal center of the cortical lymphatic nodule showed the highest expression.
TS28: lymph node medulla	Weak	Widespread	12E , 12G
TS28: lymph node capsule	Absent		12G

Structure	Cell Type	Level	Pattern	Image	Note
TS21: primary sex cord		Strong		13A , 13B
TS21: germ cell of testis		Strong		13B	Expression was higher in germ cells than in Sertoli cells.
TS21: Sertoli cell	Sertoli cell	Weak		13B	Expression was higher in germ cells than in Sertoli cells.

Structure	Level	Pattern	Image	Note
TS21: testis	Absent		13C

Structure	Level	Pattern	Image	Note
TS23: testis	Strong	Regionally restricted	13E , 13D	Expressed in the testicular cord.
TS23: germ cell of testis	Strong		13E	Expression was higher in germ cells than in Sertoli cells.

Structure	Cell Type	Level	Pattern	Image	Note
TS27: germ cell of testis		Strong		13H , 13G	Expression was higher in germ cells than in Sertoli cells.
TS27: Sertoli cell	Sertoli cell	Weak		13H , 13G	Expression was higher in germ cells than in Sertoli cells.

Structure	Cell Type	Level	Pattern	Image	Note
TS28: spermatocyte		Strong		13K , 13J
TS28: Leydig cell	Leydig cell	Strong		13J , 13K
TS28: spermatogonium		Weak		13K
TS28: spermatid		Absent		13K
TS28: spermatozoon		Absent		13K

Structure	Level	Pattern	Image	Note
TS21: ovary	Trace		13M	Very weak.

Structure	Level	Pattern	Image	Note
TS21: ovary	Absent		13N

Structure	Level	Pattern	Image	Note
TS23: ovary	Trace		13O	Very weak.

Structure	Level	Pattern	Image	Note
TS27: ovary	Trace		13Q	Very weak.

Structure	Level	Pattern	Image	Note
TS28: ovary	Present	Regionally restricted	13S , 13T	Expressed in granulosa cells.
TS28: cumulus oophorus	Present		13T
TS28: corpus luteum	Absent		13S
TS28: oocyte	Absent		13S

Structure	Level	Pattern	Image	Note
TS21: skeletal muscle	Strong		14A

Structure	Level	Pattern	Image	Note
TS21: skeletal muscle	Absent		14B

Structure	Level	Pattern	Image	Note
TS23: skeletal muscle	Moderate		14C

Structure	Level	Pattern	Image	Note
TS27: skeletal muscle	Absent		14E

Structure	Level	Pattern	Image	Note
TS28: skeletal muscle	Absent		14G

Structure	Level	Pattern	Image	Note
TS21: cartilage	Present		15A , 15B
TS21: embryo mesenchyme	Present	Regionally restricted	15A , 15B	Expressed in perichondrium.

Structure	Level	Pattern	Image	Note
TS21: cartilage	Absent		15C

Structure	Level	Pattern	Image	Note
TS23: limb skeleton	Strong	Regionally restricted	15D , 15E	Expressed in the diaphysis, but not in the epiphysis. Expressed in both osteoblasts and myeloid cells. No expression in osteocytes.

Structure	Level	Pattern	Image	Note
TS27: long bone diaphysis	Strong	Regionally restricted	15G , 15H	Expressed in both osteoblasts and myeloid cells. Low expression in the osteoclasts. No expression in osteocytes.
TS27: long bone epiphysis	Absent		15G

Structure	Level	Pattern	Image	Note
TS28: bone tissue	Absent		15J
TS28: limb long bone	Absent		15J

Structure	Level	Pattern	Image	Note
TS28: bone marrow	Strong		15K	Expressed in megakaryocytes and myeloid cells. Also expressed in fat cells.

Structure	Level	Pattern	Image	Note
TS27: cranium	Present		15M	Expressed in osteocytes.

Structure	Level	Pattern	Image	Note
TS21: salivary gland	Strong		16A	Expressed in both the epithelium terminal clusters and epithelial stalks. Weak expression in the surrounding mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS21: salivary gland	Absent		16B

Structure	Level	Pattern	Image	Note
TS23: salivary gland	Strong		16C	Expressed in both the epithelium terminal clusters and epithelial stalks. Weak expression in the surrounding mesenchymal cells.

Structure	Level	Pattern	Image	Note
TS27: salivary gland	Present		16E	Expressed in both the epithelium terminal clusters and epithelial stalks with a reduced intensity.

Structure	Level	Pattern	Image	Note
TS28: salivary gland	Present		16G	Expressed in the mucous and serous cells, but not in the myoepithelial cells.

Structure	Level	Pattern	Image	Note
TS23: interventricular septum	Weak

Structure	Level	Pattern	Image	Note
TS27: body of stomach	Strong	Regionally restricted		Expressed in surface epithelium.
TS27: stomach submucosa	Absent
TS27: ventricle endocardial lining	Absent
TS27: visceral serosal pericardium	Absent
TS27: aorta	Weak	Regionally restricted		Expressed in the tunica media.
TS27: interventricular septum	Weak