Fig 4.

RA reporter transgene activity and Raldh1/Raldh3 gene expression in developing trunk organs. (A–D) Sections through the heart of an E14.5 Raldh2^−/− transgenic embryo. Raldh1 and RARE-lacZ transgene expression in the atrioventricular valve region is indicated (arrowheads). (E–H) Sections through the abdominal cavity of a littermate WT transgenic embryo. The mesonephric duct area is enlarged (Insets). ao, ascending aorta; br, bronchus; go, gonad; gt, genital tubercle; in, intestine; ki, kidney; li, liver; lu, lung; sc, spinal cord; st, stomach; tr, trachea; ve, ventricle. (Magnifications: ×5, E–H; ×10, A–D.)