Reporter:	GFP
Antibody:	anti-GFP (#A11122)
Detection system:	Biotinylated secondary antibody/[Strept]avidin coupled to horseradish peroxidase

Structure	Level	Pattern	Image	Note
TS15: proepicardium	Present		1a
TS15: heart mesentery	Present	Regionally restricted	1a	Expressed at the venous pole in the mesocardium.
TS15: cardiac muscle tissue	Present	Regionally restricted	1a	Expressed in the myocardium of the sinus venosus.
TS15: sinus venosus	Present	Regionally restricted	1a	Expressed in the myocardium of the sinus venosus.
TS15: intraembryonic coelom	Present		1a	Expressed in coelomic mesothelium.

Structure	Level	Pattern	Image	Note
TS17: interatrial septum	Present	Regionally restricted	2a	Expressed in the mesenchymal cap, covering the rim of the primary atrial septum. Expressed in the atrial septal myocardium.

Structure	Level	Pattern	Image	Note
TS15: sinus venosus	Present	Regionally restricted	S1c	Expressed in the myocardium of the sinus venosus.
TS15: dorsal mesocardium	Present		S1c
TS15: cardiac muscle tissue	Present	Widespread	S1c	Expressed in the myocardium of the sinus venosus, the atrial and ventricular myocardium including the inner curvature. No expression in the outflow tract myocardium.

Structure	Level	Pattern	Image	Note
TS15: cardiac muscle tissue	Present	Regionally restricted	S1f	Expressed in the atrial and ventricular myocardium including the inner curvature.

Structure	Level	Pattern	Image	Note
TS17: cardiac muscle tissue	Present		S2b , S2c , S2a	Expressed in the myocardium of venous valves and atrial septum including the mecenchymal cap.
TS17: common atrial chamber right part venous valve	Present		S2b , S2c , S2a	Expressed in the myocardium of venous valves and atrial septum including the mecenchymal cap.
TS17: interatrial septum	Present		S2b , S2c , S2a	Expressed in the myocardium of venous valves and atrial septum including the mecenchymal cap.
TS17: outflow tract	Present	Regionally restricted	S2c , S2a , S2b	Positive staining, but not in the outflow tract myocardium.
TS17: atrioventricular canal	Present	Regionally restricted	S2a , S2b	Expressed in the atrioventricular cushion mesenchyme.

Structure	Level	Pattern	Image	Note
TS17: primitive ventricle endocardial lining	Present		S2f , S2d , S2e
TS17: primitive ventricle cardiac muscle	Absent		S2e , S2d , S2f

Structure	Level	Pattern	Image	Note
TS17: outflow tract	Present	Regionally restricted	S2i , S2h , S2g	Positive staining, but not in the outflow tract myocardium.
TS17: atrioventricular canal	Present	Regionally restricted	S2i , S2g , S2h	Expressed in the atrioventricular cushion mesenchyme.

Structure	Level	Pattern	Image	Note
TS22: cardiac muscle tissue	Present	Regionally restricted	S4b , S4a , S4c	Expression was only seen in the sinoatrial node and myocardium of the cardinal veins.
TS22: visceral pericardium	Present	Regionally restricted	S4b , S4a	Expressed in the epicardium covering the ventricles.
TS22: interventricular septum	Present	Scattered	S4a , S4b
TS22: aortic valve	Present		S4c
TS22: endocardial tissue	Present		S4c
TS22: pulmonary valve	Present		S4c
TS22: right atrium venous valve	Present		S4c

Structure	Level	Pattern	Image	Note
TS22: cardiac muscle tissue	Present	Regionally restricted	S4d , S4e , S4f	Expression was only seen in the sinoatrial node and myocardium of the cardinal veins.
TS22: atrioventricular endocardial cushion	Present		S4e , S4d
TS22: dorsal mesocardium	Present		S4e , S4d
TS22: aortic valve	Present	Regionally restricted	S4f	Specifically on the non-flow side.
TS22: endocardial tissue	Present	Regionally restricted	S4f	Specifically on the non-flow side.
TS22: pulmonary valve	Present	Regionally restricted	S4f	Specifically on the non-flow side.
TS22: right atrium venous valve	Present	Regionally restricted	S4f	Specifically on the non-flow side.

Structure	Level	Pattern	Image	Note
TS22: aortic valve	Present	Regionally restricted	S4h , S4g	Specifically on the non-flow side.
TS22: endocardial tissue	Present	Regionally restricted	S4h , S4g	Specifically on the non-flow side.
TS22: pulmonary valve	Present	Regionally restricted	S4h , S4g	Specifically on the non-flow side.
TS22: right atrium venous valve	Present	Regionally restricted	S4h , S4g	Specifically on the non-flow side.
TS22: cardiac muscle tissue	Present	Regionally restricted	S4i , S4g	Expressed in the sinoatrial node and myocardium of the cardinal veins.

Structure	Level	Pattern	Image	Note
TS22: cardiac muscle tissue	Present	Regionally restricted	S5d	Expressed in the myocardial cluster between the left left cardinal vein and pulmonary vein. No expression in the myocardium of the pulmonary vein.
TS22: heart mesentery	Present	Regionally restricted	S5d	Expressed in the mesenchyme surrounding the pulmonary vein.