Figure 7

Rab11 is also required for R-cell positioning. (A-C) Longitudal optic sectioning of third-instar larval eye discs double-stained with anti-Elav (blue) and anti-HRP (green) to visualize R-cell nuclei and R-cell surface, respectively. (A) In wild type, R-cell bodies localizes to the apical region, while their apical processes attach to the apical surface and their axons project basally. (B) The generation of clones of Rab11^ex2 mutant cells caused R-cell nuclei to be mis-localized at the basal region. (C) In eye discs expressing a UAS-Rab11-RNAi transgene, R cells did not appear to be tightly associated clusters at the apical region and instead formed a long stretch along the apical-basal axis (20 out of 41 eye discs examined). Note that R-cell processes still attached to the apical surface in Rab11 mutants (B and C). (D) Basal localization of Rab11 mutant nuclei in Rab11^ex2 mosaic eye disc. GFP (green) was used to label wild-type or Rab11 heterozygous ommatidia in Rab11 mosaic eyes. R-cell nuclei at the basal region were visualized with anti-Elav staining (red). In GFP-positive ommatidia, no R-cell nuclei were observed in the basal region. In the basal region of homozygous Rab11 mutant ommatidia or mosaic ommatida (GFP negative), mis-localized R-cell nuclei (red) were observed. Scale bar: A-C,10 μm; D, 5 μm.