(a-d) dRagAQ61L suppresses autophagy. (a) Drosophila fat body cells clonally expressing dRagAQ61L (marked in green by GFP expression) failed to accumulate autolysosomes (shown in surrounding control cells by punctate Lysotracker Red staining) in response to starvation for 4 h. Nuclei are marked in blue by DAPI. (b-d) Induction of autophagosomes in response to 4-h starvation is shown by the punctate pattern of GFP-Atg8a expression in control fat body cells (b), but not in cells expressing dRagAQ61L (c). The average number of GFP-Atg8a-marked autophagosomes per cell in control and dRagAQ61L-expressing clones is shown (d). Data are mean ± s.d., *P = 2.91 × 10−6, Students two-tailed t-test (n = 33 fat body samples imaged per genotype). Scale bars represent 25 μm in each panel. 