Figure 4. A non-autonomous role of dp53 in regulating proliferation rates.

(A–D) Wing discs expressing GFP (A), Ricin^cs (B, D), or PTEN (C) with the en-gal4 driver and labeled to visualize reaper mRNA expression. The wing disc shown in (D) is also mutant for dp53 (dp53^ns). (E–M) Wing discs expressing GFP and Ricin^cs with the en-gal4 driver in different genetic backgrounds (dp53^ns in F, J; co-expressing dp53^259H in G, K; or dp53^dsRNA in H, L) and labeled to visualize GFP, TUNEL-positive cells and BrdU incorporation. (M) Histograms plotting the number of mitotic figures (PH3-positive cells) observed in the A and P compartments of wing discs expressing Ricin^cs in a wild-type (red bars) or a dp53^ns mutant background (green bars). Number of PH3-positive cells: en> Ricin^cs: A = 31±6, P = 58±6; en> Ricin^cs;dp53^ns: A = 64±8, P = 70±7. Ten wing discs were scored per genotype. (N) Histograms plotting the size of clones (in arbitrary units) located in the A compartment of en-gal4;UAS- Ricin^cs UAS-GFP (blue bars), en-gal4;UAS- Ricin^cs UAS-GFP (red bars), and en-gal4; UAS-Ricin^cs UAS-dp53^RNAi(green bars) wing discs. Clones were generated at the beginning of the Ricin^cs induction period and quantified 72 or 96 h later in third instar wing discs. Error bars indicate standard deviation. Size of clones at 72 h: en>GFP = 0.67±0.3 (n = 28); en> Ricin^cs  = 0.33±0.2 (n = 34); en> Ricin^cs;p53^RNAi  = 0.54±0.2 (n = 39). Size of clones at 96 h: en>GFP = 1.31±0.3 (n = 17); en> Ricin^cs  = 0.63±0.2 (n = 15); en> Ricin^cs;p53^RNAi  = 0.9±0.3 (n = 18).