Fig. 3
From: Meis2 is essential for cranial and cardiac neural crest development
Immunohistochemistry of transverse and sagittal sections at E13.5 from the embryonic heart in Meis2-/- mice and controls. a Anti-Meis2 antibody staining (brown) show strong expression in the pulmonary and aortic valve. The aortic valve is absent in the mutants lacking Meis2 (arrowhead). b α-Smooth muscle actin (SMA) staining showing the persistent truncus arteriosus (PTA) with the fused aorta and pulmonary artery (presumptive ao* and pa*). Sagittal sections document a shortened heart length and a malformed pulmonary valve. c Heart-specific myosin light chain 7 (Myl7) staining shows normal cell specification in the myocardium in Meis2 nulls and, again, absent aortic and abnormal pulmonary valve on transverse and sagittal sections, respectively. d Left: Decrease of Sox9-positive cells in the valves in the outflow tract in Meis2 nulls. Right: The level of Twist1 expression in the condensed mesenchyme in the pulmonary valve and in the tricuspid valve appears normal in the mutants but it clearly reveals severe morphological changes in OFT. av, aortic valve; pv, pulmonary valve; tv, tricuspid valve; ao, aorta; pa, pulmonary artery