Figure 6

Rab5 and Shi are required for apical localization of R-cell nuclei in the eye disc. (A-F) Apical (A, C and E) and basal (B, D and F) view of third-instar larval eye discs stained with anti-Elav antibody. The distance between apical and basal sections is ~15 μm. (A and B) In wild type, R-cell nuclei are localized to the apical region (A) and thus are not present in the basal region (B). (C and D) In a Rab6 null (Rab6^D23D) mutant eye disc, R-cell nuclei appeared normally at the apical region (C). (E and F) In an eye disc expressing the dominant-negative form of Rab5 (Rab5S43N), many R-cell nuclei were missing in the apical region (E) and mis-localized to the basal region (F). (G-I) Longitudinal optic sectioning of third-instar eye discs double-stained with anti-Elav (blue) and anti-HRP (green) to visualize R-cell nuclei and R-cell surface, respectively. (G) Wild type. (H) In eye discs expressing Rab5S43N, ~27% ommatidia contained mis-localized R-cell nuclei (n = 5 eye discs). (I) Eye discs expressing the dominant-negative form of shi (i.e. shi^ts1) displayed a R-cell mis-localization phenotype (~34% ommatidia, n = 7 eye discs). Scale bars: A-F, 50 μm; G-I, 10 μm.