Fig. S8

Eye transplantations as a means to assess the cellular requirements for Robo2 in the functional development of DS tectal cells (related to Figure 6). (A) Schematic showing the experimental procedure followed. Optic vesicles from donor embryos were transplanted into hosts at 12-14 hpf and functional imaging was performed at 4 and 7 dpf. To confirm the success of each transplantation experiment, samples were fixed post-functional imaging at 7dpf and the donor and host eyes were bulk-loaded with the lipophilic dyes, DiI and DiD respectively, in order to label the entire retinotectal projection. (B-D) Three transplantation examples (one per transplantation group) showing the retinotectal projection of host and donor eyes. Scale bar represents 100 µm. A, anterior; L, lateral. (E) Schematic showing the experimental procedure followed to investigate the functional development of donor DS-RGC axons. Optic vesicles from ,em>Tg(Isl2b:Gal4;UAS:SyGCaMP3) donor embryos were transplanted into hosts at 12-14 hpf and functional imaging of donor RGC axons within the tectum was performed at 4 and 7 dpf. (F-G) Quantification of average number of DS-RGC voxels per group. Total number of DS-RGC voxels at 4 dpf (F), 697 ± 252.6 for WT-to-WT (n = 6 larvae, total of 18 optical sections), 1996 ± 689.9 for WT-to-ast^ti272z (n = 5 larvae, total of 15 optical sections) and 544.3 ± 325.4 for ast^ti272z-to-WT (n = 4 larvae, total of 12 optical sections). Total number of DS cells at 7 dpf (G), 1783 ± 870.9 for WT-to-WT (n = 8 larvae, total of 24 optical sections), 3606 ± 1190 for WT-to-ast^ti272z (n = 4 larvae, total of 12 optical sections) and 1653 ± 692.9 for ast^ti272z-to-WT (n = 5 larvae, total of 15 optical sections). All graphs show mean values ± SEM. ns, not significant, Kruskal-Wallis and Dunn′s multiple comparison tests.