Figure 2. Loss of E2f3 causes structural defects in the developing heart.
(A–B) Ventricular (A) and atrial (B) septal defects are present in E2f3−/− (right) but not control (left) neonates (100X). Arrows point to the septal defects. (C–D) Quantitation of cycling cells by Ki67 staining in E2f3−/− and control heart muscle. Dark brown stain indicates Ki67 positive nuclei. The remaining nuclei are counterstained with blue hematoxylin. Numbers above the graph represent the average percentage. (E) Real time RT-PCR analysis of E2f3a and E2f3b transcripts in adult (n=4) and day 1.5 (n=3) ventricular heart tissue. Fold change = 2ˆ(ΔΔCt).