Fig. 1. The OBLS forms ectopically at the lateral part of the telencephalon of Pax6 mutants. (A-D) Lateral views and (E-L) coronal sections of wild-type (WT, A,C,E,F,I,J) and Pax6-mutant telencephalons (-/-, B,D,G,H,K,L), stained with anti-neruopilin 1 (Nrp, A,B,I,K), anti-Calretinin (CR, I,K), anti-GAD67 antibodies (J,L) or hybridized with specific probes for neuropilin 1 (Nrp, E,G), netrin G1 (C,D,F,H). A-H and I-L show E16.5 and E18.5 embryos, respectively. Nrp and netrin G1 are expressed in the protruding OB in the wild type (arrowheads in A,C), whereas these markers are observed at the lateral part of the mutant telencephalon (arrowheads in B,D). Note that Nrp protein is localized mostly at the neuropiles and axons of mitral cells (arrowheads and arrows in A,B). The distribution of Nrp and netrin G1 overlap in the OB and the OBLS (E-H). Nrp, CR and GAD67 are expressed in the different types of neurons of the OB and the OBLS (I-L). egl, external granule cell layer; epl, external plexiform layer; grl, glomerular layer; mcl, mitral cell layer. Scale bars: A-D, 1 mm; E-L, 50 µm.