Fig. 1

Expression of Pax6 and Cdca7 at E12.5 in wild-type and Pax6 ^−/− telencephalon. In situ hybridizations on coronal (A, A′, C, C′, E, E′, G, G′) and sagittal sections (B, B′, D, D′, F, F′, H, H′). A, A′, B, B′ Pax6 expression is graded in the cortex (Ctx) from high rostro-laterally to low caudo-medially with highest expression level at the lateral cortex (LC) in A, A′ and the anterior cortex (AC) in B, B′ and a sharp reduction at the pallial-subpallial boundary (PSPB) in wild-types. Inset in A shows immunohistochemistry for Pax6 protein in wild-type at E12.5. LGE, lateral ganglionic eminence. A′–B′ High magnification of areas outlined in A, B. C, C′, D, D′ Pax6 expression is abnormal in the cortex and decreases less sharply at the PSPB in Pax6 ^−/− embryos. Inset is C shows immunohistochemistry on E12.5 Pax6 ^−/− telencephalon; although Pax6 mRNA is produced, there is no detectable protein. C′–D′ High magnification of areas outlined in C, D. E, E′, F, F′ The telencephalic Cdca7 expression pattern in the wild-type appears opposite to that of Pax6, with low levels on the cortical side of the PSPB, in the lateral cortex. E′, F′ High magnification of areas outlined in E, F. G, G′, H, H′ Cdca7 expression is abnormal in the cortex and shows no obvious decrease on the cortical side of the PSPB in Pax6 ^−/− embryos. G′, H′ High magnification of the areas outlined in G, H. Scale bars 50 µm