Figure 7

(A-K) Progression of nuclear β-catenin (green) accumulation in the telencephalon of control (A, B, D, E, G, I, J) and mutant (C, F, H, K) embryos at embryonic day (E) 10.5 (A-C), E12.5 (D-H), and E13.5(I-K). (A, D, I) In the control, β-catenin staining is widespread throughout the cerebral cortex (B, E, G, J) Higher magnification images show that β-catenin is predominantly located at the cell surface and excluded from the nucleus. In contrast, the mutant has significant numbers of cells with β-catenin in the nucleus. These are first apparent at E10.5 (C) (white arrows indicate examples), becoming more pronounced at E12.5 (F) and E13.5 (K). (H) A higher magnification image, showing a typical example of nuclear β-catenin at E12.5. All sections are coronal and dorsal is up. Scale bars (A, D) 250 μm; (B, C, E, F, J, K) 100 μm; (G, H) 5 μm.