Figure 9
Segregation of functionally-distinct retinal ganglion cells (RGCs) in the superior colliculus (SC) of Isl2EphA3/EphA3mice. (A and B) Schematics of topographic mapping in wild type (A) and Isl2EphA3/EphA3 mice (B). In wild type mice, the temporal-nasal axis of the retina maps onto the anterior-posterior axis of the SC. In Isl2EphA3/EphA3, Isl2+ RGCs express exogenous EphA3, and thus innervate the anterior SC, while Isl2- RGCs express endogenous levels of EphA receptors and innervate the posterior SC. (C and D) Parasagittal sections through the SC of adult (P30) wild type (C) and Isl2EphA3/+ mice (D) in which all RGC terminations are labeled by CTB-555 (red) and Isl2-GFP RGC terminations are labeled by immunofluorescence of GFP (green). (E) Immunofluorescence of Isl2 (red) expression reveals co-localization in CB2-GFP RGCs (green) in a P8 retina. (F and G) Parasagittal sections through the SC of adult (P30) wild type (F) and Isl2EphA3/EphA3 mice (G) reveal the terminations of CB2-GFP RGCs (green) in relation to all RGCs (red). (H) Immunofluorescence of Isl2 (red) expression reveals an absence of co-localization in DRD4-GFP RGCs (green) in a P8 retina. (I and J) Parasagittal sections through the SC of adult (P30) wild type (I) and Isl2EphA3/EphA3 mice (J) reveal the terminations of DRD4-GFP RGCs (green) in relation to all RGCs (red).