Fig. 5. Neurogenesis resumes after the removal of caNotch. P5 brains after single electroporation of pCAG-ExNotchZ at E13.5 (A,E-G), and after double electroporation of pCAG-ExNotchZ at E13.5 and pXCANCre at E15.5 (B-D,H-K). (E-G) Magnified view of an EYFP⁺ region close to the lateral ventricle (LV). (H-K) Magnified views of layers II and III. Green and blue signals show EYFP fluorescence (A,B,E,G,H), and immunostaining with the anti-ß-gal antibody (C,D,I,K), respectively. Red signals show immunostaining with antibodies recognizing FLAG (F-H) and Lhx2 (D,J,K). B-D, E-G, and I-K each show the same section; D,G,H and K are merged views. Note, EYFP⁺ neurons only signal green, no yellow colouration was observed even after the merge of two colors (H) because of a lack of FLAG signals. All ß-gal⁺ neurons of layers II and III were positive for Lhx2. 80.5±2.0% of ß-gal⁺/Lhx2⁺ neurons expressed Lhx2 at high levels. The ratio was almost identical to that of strongly Lhx2-positive cells in the total Lhx2⁺ population of layers II and III (79.6±2.45%). A similar distribution of cells was also confirmed in five brains by using EYFP fluorescence and X-gal staining (data not shown). Scale bars: 200 µm for A-D; 20 µm for E-H,I-K.