Figure 2

pbx2/4 null embryos exhibit RGC axonal outgrowth defects. In wild type embryos at 5.5 dpf, temporal RGC axons map to the anterior optic tectum (A) and (C), while nasal RGC axons map to the posterior region of the optic tectum (B) and (C). This is also seen at 3.5 dpf (G-I) although the connections on the tectum are more diffuse. In lzr-/- mutants injected with pbx2/4 morpholinos, both posterior and anterior RGC axons fail to map onto the optic tectum at both 3.5 dpf (J-L) and 5.5 dpf (D-F).