Fig. 5. Loss of Gli2 does not rescue the Shh mutant defects and expression of Gli1 from the Gli2 allele can only partially rescue the Shh forebrain mutant defects at E10.5. (A,E) Wild-type embryos. (B,F) Shh^–/– embryos. (C,G) Gli2^{lzki/lzki;Shh–/–} embryos. (D,H) Gli2^1ki/+;Shh^–/– embryos. In Shh^–/– embryos, the telencephalic vesicles are fused (arrows in B,F). In half the Gli21ki^+/–;Shh^–/– embryos, the telencephalic vesicles are partially separated. The embryo in D represents the most fully rescued embryo. (E-H) Higher magnification views of the telencephalic regions of the same embryos as in (A-D), shown in frontal view. F is a frontal view, in order to visualize the lack of separation of the two vesicles, and the broken red lines in E,H indicate the midline. (I-L) lacZ is expressed in Gli2^lzki/+ and Gli2^lzki/+;Shh^–/– embryos at E8.5 (I,J) and sections at E10.5 (K,L). DRG, dorsal root ganglion. The margins of the spinal cord are outlined by broken red lines. Scale bar: 50 µm.