Fig. 8. Par6 overexpression in vivo increases the number of Pax6+ VZ progenitors. (A,B) Coronal sections of E16 cerebral cortices injected with either control (A) or Par6-containing (B) retroviruses at E13, immunolabeled for GFP (green) and stained with DAPI (blue). (C) Quantification of GFP-positive cells in the dorsal telencephalon of control (n=4, 1642 cells) and Par6 (n=3, 3568 cells) -injected brains. Note the increased proportion of GFP-positive cells in the VZ of Par6-injected animals (^***, P<0.001; unpaired t-test), whereas the proportion of GFP-positive cells in the cortical plate and intermediate zone was reduced (^*, P<0.05; unpaired t-test). (D-G) Higher-power micrographs of coronal sections of E16 cortices injected with Par6-containing retroviruses and double labeled as indicated. Insets are higher magnifications of the boxed areas. VZ, ventricular zone; SVZ, subventricular zone; IZ, intermediate zone; CP, cortical plate; LV, lateral ventricle; GE, ganglionic eminences. Scale bars: 100 µm in A,B; 50 µm in D-F; 75 µm in G.