Fig. 4. Cell-autonomous blockade of Shh signaling also reduces Nkx2.1 expression in the MGE of telencephalic slices. Shown are 12 µm sections made from slices cultured from E12.5 + 1 DIV. Slices had been transfected with either pCAGGS-ires-GFP control vector (A-C) or pCAGGS-mPTC1^loop2-ires-GFP (D-F) by electroporation. Sections were immunolabeled with GFP (A,E) and Nkx2.1 (B,F). The boxed areas in A and D are enlarged, and the GFP signal intensity equally reduced to show co-labeling of GFP with Nkx2.1 in C and F, respectively. The area of pCAGGS-mPTC1^loop2-ires-GFP expression in D has a marked decrease in Nkx2.1-expressing cells (E), and a corresponding loss of GFP-Nkx2.1 co-labeled cells (compare C with F). (G) Quantification of the percentage of GFP-expressing cells that co-labeled with Nkx2.1 in the MGE of these slices found a significant reduction in the mPTC1^loop2 transfected slices (n=6; **P<0.004). Scale bar: 50 µm.