Figure 1.

prosβ2 mutant cells accumulate ubiquitin-conjugated proteins. Shown are high magnification images (x100) of the posterior compartment of prosβ2 mosaic eye imaginal discs labeled for ubiquitin (a), FK2 (b) and FK1 (c). In this and all other figures, posterior is to the right. The FK2 and FK1 antibodies detect ubiquitin-conjugated proteins, but not free unconjugated ubiquitin. The left panels indicate the positions of the proteasome mutant cell clones by absence of GFP, the middle panels show the experiment (in magenta), and the right panels are the merged images of left and middle panels. White arrows mark a few cell clones as examples. Similar data were obtained for Mov34 mosaic discs (Supplementary Figure S1). Wild-type mosaic control discs do not show accumulation of ubiquitin (Supplementary Figure S2). Genotype: ey-FLP; prosβ2^EP3067 FRT80/ubi-GFP FRT80