SNAP23 deficiency decreases β-catenin and Notch signaling. (A and B) Immunoblots showing the levels of total and active β-catenin in the control (Ctrl) and NcKO brains at E13.5. Lamin B blotting was used as a loading control. (C and D) Immunoblots showing the full-length (FL) and cleaved Notch1 (NICD) levels in the Ctrl and NcKO brains at E13.5. Lamin B blotting was used as a loading control. (E and F) Relative expression of Axin2 and Hes5 mRNA in the Ctrl and NcKO brains at E13.5, as measured with real-time PCR (n = 5 mice per genotype). (G) d1EGFP expression in the cerebral cortex with or without NICD plasmid. Scale bar, 200 µm. (H) TUNEL stained in the electroporated region of the cerebral cortex. pX330 was electroporated as a control. The mCherry plasmid was electroporated to show the electroporated region. The blue arrowheads indicate TUNEL-positive cells. Scale bar, 50 µm. (I) Density of TUNEL-positive cells in the electroporated region of the cerebral cortex (n = 5 sections from three mice per genotype).