Fig. 2

Cardiovascular and pulmonary anomalies in the Pcsk5; Sox2Cre conditional KO embryos. (a) Three-dimensional reconstruction of the control, Pcsk5 ^wt/flox ; Sox2Cre + heart at E15.5. At this stage, ventricular septum (VS) is fully formed, aorta (Ao) leaves left ventricle (LV), and pulmonary artery (PA) leaves right ventricle (RV). Both great arteries go to the left side of the trachea (Tr); (a’) Psck5 ^Δ1/flox; Sox2Cre heart showing ventricular septal defect (VSD), common arterial trunk (CAT) and aorta forming right-sided arch. Pulmonary artery (PA) joins the aorta on the correct, left side of the trachea. (b) MRI sagittal section through control heart with tricuspid and mitral valves (TV, MV) and a correct septation. (b’) Corresponding section through the Psck5 ^Δ1/flox; Sox2Cre embryo with atrial septal defect (ASD) and common, thickened atrioventricular valve (CV); on both sections, left and right ventricles (LV, RV) and right and / or left atria (RA, LA) are shown, as well as superior venae cavae (SVC, LSVC – left SVC). (c, c’) 3D reconstructions of normal and conditional knock-out) cKO lungs; both embryos have three pulmonary lobes on the right side (Cr – cranial, Mi – middle, Ca – caudal lobe) and accessory lobe (Ac) extending to the left side. Left lung (LL) has only one lobe. Heart position (H) is shown. Psck5 ^Δ1/flox ; Sox2Cre embryo (c’) has clearly reduced lungs’ size in comparison to its normal littermate (c). Psck5 ^Δ1/flox; Sox2Cre embryos do not have a tracheo-oesophageal fusion as it was observed in a Vcc and zygotic mutants. Both control embryo (d) and Psck5 ^Δ1/flox; Sox2Cre littermate (d’) have trachea (Tr) and oesophagus (O) properly separated, as shown on this MRI sagittal sections. All scale bars = 0.5 mm