Fig. 5. In the absence of En2, expression of mouse En2 but not Drosophila en in place of En1 can rescue mes/r1 defects. Stained sagittal sections of wild-type (wt) (A,G), En1^2ki/2ki;En2^-/+ (B,H), En1^2ki/2ki;En2^-/- (C,I), En1^2ki/-;En2^-/- (D,J), En1^Denki/Denki;En2^-/+ (E,K), and En1^Denki/+;En2^-/- (F,L) at the level of the vermis (A-F) and hemispheres (G-L). A-C,E,G-I,K are stained with Cresyl Violet; D,F,J,L with Hematoxylin and Eosin. For comparison, the En2^-/- phenotype is shown in Fig. 4. See Fig. 2 legend for midbrain and cerebellum annotation, and Fig. 4 legend for key to asterisks and arrows.