Fig. 3. Expression of laminae I-II markers and rescue of Drg11 and Ebf3 expression by forced expression of Lmx1b in the dorsal horn of Lmx1b^-/- embryos. (A,B) Drg11 expression in the dorsal horn of wild-type (A, arrow) and Lmx1b^-/- (B, arrow) embryos. (C,D) Ebf3 expression is restricted to laminae I-II neurons in wild-type dorsal horn (arrow in C), but is absent in Lmx1b mutant embryos (arrow in D). (E,F) In wild-type embryos (E) Ebf1 is concentrated in laminae I-II (arrow in E,F), but its expression is markedly reduced in Lmx1b mutant embryos (F, arrow). (G,H) Rnx expression in laminae I-II neurons (arrows) of wild-type (G) and Lmx1b mutant embryos (H). (I,L-Q) Reactivation of Drg11 and Ebf3 expression in Lmx1b^-/- spinal cord by exogenously introduced Lmx1b. (I) Lmx1b expression in Lmx1b^-/- spinal cord after electroporation of Lmx1b-expression vectors. No Lmx1b was found in the contralateral side of the spinal cord. (J,K) Expression of EGFP control plasmids in Lmx1b^-/- spinal cord. (K) No Lmx1b was detected in the electroporated side of Lmx1b^-/- spinal cord after electroporation of EGFP. (L) Induction of Drg11 (arrow) in Lmx1b^-/- spinal cord electroporated with Lmx1b expression vectors. No Drg11 staining was found in the contralateral side of the spinal cord (arrow). (M,N) Higher magnification of the regions indicated by arrows in L. Arrowheads indicate Drg11⁺ cells. (O) Induction of Ebf3 expression (arrow) in the dorsal horn of Lmx1b^-/- embryos after electroporation. (P,Q) Higher magnification of the regions indicated by arrows in O. Arrowheads in P indicate Ebf3⁺ cells. Scale bars: 100 µm in A-H,I-K,L,O; 30 µm in M,N,P,Q.