Fig. 7. Rescue of cell migration defects in Psen1^–/– embryos with a nestin-Psen1 transgene. Pregnant females were given one dose of BrdU at E12.5 and the embryos were collected at E18.5 and immunostained with anti-BrdU antibodies. Shown are BrdU-immunostained sections through the lateral cerebral wall of E18.5 embryos from wild-type (A), Psen1^+/– (B), Psen1^–/– (C), nestin-Psen1 transgene on Psen1^–/– background (D) and nestin-Psen1 transgene on Psen1^+/+ background (E). BrdU labeling is dispersed in the Psen1^–/– embryo and normalized by the nestin-Psen1 transgene. Cortical layers (MZ, CP, SP, IZ, VZ) are indicated as in Fig. 5. Scale bar: 100 µm.