Fig. 5. Altered vivo striatal patterning in ephrin A5/EphA4 mutants. (A-C) When injected with BrdU at E16/E17 and sacrificed at P2, control animals (double heterozygotes for ephrin A5 and EphA4, n=9) display a matrix-like distribution of BrdU. (D-F) Ephrin A5 KO animals (n=5) display a similar distribution of BrdU+ neurons. (G-I) EphA4 KO animals (n=4) display a much more uniform distribution of the BrdU+ matrix neurons across the striatum and more diffuse DARPP32 staining. In addition, many more BrdU+ neurons are found at ectopic locations within DARPP32-positive striosomes. (J-L) Ephrin-A5/EphA4 DKO animals (n=6) show an almost completely uniform distribution of the BrdU+ matrix neurons across the striatal mantle (J), a more diffuse DARPP32 staining (K) and numerous ectopic BrdU+ matrix neurons within the striosomes (inset in L). Arrowheads show DARPP32+ positive striosomes. Scale bar: 100 µm.