Fig. 3.

ApjCreER lineage-traced vessels give rise to coronary artery, capillaries and veins of the ventricular walls. Whole-mount confocal images (A,B,D,E) or tissue sections (C,F) of hearts from ApjCreER, Rosa^mTmG crosses dosed with tamoxifen at E9.5 and isolated at the indicated ages. The lineage label is shown in green. (A,B) Many coronary vessels (DACH1⁺, red) on the dorsal and lateral sides of the heart are ApjCreER lineage traced (green), whereas parts of the apex and central region of the ventral side are not (asterisks). (C) Tissue sections through the left and right ventricular walls (lw and rw, respectively) and septum (sep, outlined by dotted line) show the paucity of ApjCreER lineage-traced vessels in the latter structure. (D) A series of optical sections through the ventricles (dorsal to ventral from left to right) shows lineage-traced cells on the surface (subepicardial) and within the myocardium (intramyocardial). (E) The boxed region from D showing a partially labeled coronary artery (ca) at the border between lineage-labeled (sv-derived) and non-labeled (non-sv-derived) vessels. (F) Immunostaining tissue sections for connexin 40 (Cx40) and COUP-TFII shows ApjCreER lineage contribution to arteries and veins, respectively. lv, left ventricle; rv, right ventricle. Scale bars: 100 µm.