Probe:	Irx5 cDNA1
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS14: heart	Present	Regionally restricted		Expression is present at the ventral side of the looping tubular heart at the level of the embryonic ventricle.

Structure	Level	Pattern	Image	Note
TS15: common atrial chamber endocardial lining	Present		2I
TS15: primitive ventricle endocardial lining	Present		2I

Structure	Level	Pattern	Image	Note
TS15: common atrial chamber endocardial lining	Present		2J
TS15: primitive ventricle endocardial lining	Present		2J
TS15: common atrial chamber cardiac muscle	Absent		2J

Structure	Level	Pattern	Image	Note
TS19: left atrium endocardial lining	Present		5C
TS19: right atrium endocardial lining	Present		5I , 5C
TS19: right atrium cardiac muscle	Absent		5I , 5C
TS19: left ventricle endocardial lining	Present		5F , 5C
TS19: endocardial cushion	Absent		5C , 5F	No expression in the antrioventricular cushions.

Structure	Level	Pattern	Image	Note
TS19: left atrium endocardial lining	Present		5H
TS19: left ventricle endocardial lining	Present		5H
TS19: right atrium endocardial lining	Present		5H
TS19: right ventricle endocardial lining	Present		5H
TS19: outflow tract	Absent		5H

Structure	Level	Pattern	Image	Note
TS20: left atrium endocardial lining	Present		5J
TS20: left atrium cardiac muscle	Absent		5J
TS20: endocardial lining	Present	Regionally restricted	5L , 5J	Expression is found selectively in the endocardium lining the forming atrial and ventricular chambers. It is not found in the endocardium of the inflow tract, antrioventricular canal, inner curvature, and outflow tract.
TS20: atrioventricular canal	Absent		5J
TS20: outflow tract	Absent		5J
TS20: arch of aorta	Absent		5J	No expression in the endothelium.

Structure	Level	Pattern	Image	Note
TS20: interventricular septum cardiac muscle	Weak	Regionally restricted		There is weak expression in cardiomyocytes at the top of the ventricular septum and the trabecules astride the septum.

Structure	Level	Pattern	Image	Note
TS23: atrium endocardial lining	Present			Expression is found selectively in the endocardium lining the forming atrial and ventricular chambers. It is not found in the endocardium of the inflow tract, antrioventricular canal, inner curvature, and outflow tract.
TS23: ventricle endocardial lining	Present			Expression is found selectively in the endocardium lining the forming atrial and ventricular chambers. It is not found in the endocardium of the inflow tract, antrioventricular canal, inner curvature, and outflow tract.

Structure	Level	Pattern	Image	Note
TS21: limb interdigital region mesenchyme	Present