Antibody:	3betaHSD-1 antibody
Detection system:	Biotinylated secondary antibody/[Strept]avidin coupled to horseradish peroxidase

Structure	Level	Pattern	Image	Note
TS19: gonad	Absent		5A
TS19: mesonephros	Absent		5A

Structure	Level	Pattern	Image	Note
TS20: testis	Absent		5B

Structure	Level	Pattern	Image	Note
TS21: interstitium of the testis	Present	Scattered	6A	Expression initially detected in cells scattered in interstitium between testicular cords and near coelomic epithelium.
TS21: testis	Present	Regionally restricted	6A	No expression in juxta-coelomic zone.
TS21: coelomic epithelium of testis	Absent		6A

Structure	Cell Type	Level	Pattern	Image	Note
TS22: Leydig cell	Leydig cell	Present	Clusters	6B	Expression in clusters of cells in intersitium, in positions characteristic of Leydig cells.
TS22: testis		Present	Regionally restricted	6B	No expression at testis-mesonephros border.
TS22: coelomic epithelium of testis		Absent		6B

Structure	Cell Type	Level	Pattern	Image	Note
TS24: Leydig cell	Leydig cell	Present	Clusters	6C	Expression in clusters of cells in intersitium, in positions characteristic of Leydig cells.
TS24: testis		Present	Regionally restricted	6C	No expression at testis-mesonephros border.
TS24: coelomic epithelium of testis		Absent		6C

Structure	Cell Type	Level	Pattern	Image	Note
TS27: Leydig cell	Leydig cell	Present	Clusters	6D	Expression in clusters of cells in interstitium, in positions characteristic of Leydig cells.

Structure	Cell Type	Level	Pattern	Image	Note
TS28: Leydig cell	Leydig cell	Present	Clusters	6E	Expression in clusters of cells in interstitium, in positions characteristic of Leydig cells.

Structure	Cell Type	Level	Pattern	Image	Note
TS28: Leydig cell	Leydig cell	Present	Clusters	6F	Expression in clusters of cells in interstitium, in positions characteristic of Leydig cells.

Structure	Level	Pattern	Image	Note
TS21: interstitium of the testis	Present	Single cells	7	Expression in interstitium between testicular cords.
TS21: testis	Present	Regionally restricted	7	Expression in cells near coelomic border, but never at testis-mesonephros border.
TS21: coelomic epithelium of testis	Absent		7