Figure 3.

D1^ECKO mice were born alive but died within 2 days and displayed cardiac and vasculature defects.

(A) P0 D1^ECKO pups have shorter statues and tails than wild type litter mates (arrows). (B) Hemorrhage is present in the head region of D1^ECKO at P0 (arrows). (C–F) Hearts from wild type (C) and D1^ECKO (D–F) P0 pups reveal persistent truncus arteriosus (TA, D) in some animals, while others show septation with abnormal patterning of the aorta (Ao) and pulmonary artery (P) (E,F). All mutants pups had abnormal coronary origins (arrows, D,E) and hemorrhages on the ventricular walls (arrow heads, D, E). (G,H) H&E staining of P0 heart sections shows condensed and discontinuous atrial myocardium which was separated from the epicardium in mutants (arrow, H). Some mutant hearts also displayed ventricular septal defects (arrowhead, H). (I, J) Whole-mount PECAM staining of E11.5 wild type and D1^ECKO embryos. LV, left ventricle; RV, right ventricle; A, atrium.