Figure 4. Low UBB+1 expression increases vacuolar activity. Images of vacuole staining with FM 4-64 under wild type background (A) and atg1Δ mutant background (B). Top panel: FM 4-64 fluorescence. Bottom panel: overlay of DIC and FM 4-64 fluorescence images. White arrows indicate cells with intravacuolar staining. Scale bar = 5 μm. (C) Quantification of the percentage of cells containing intravacuolar staining in the indicated strains. The data are shown as average values ± SD from three independent experiments, with more than 200 cells per experiment. The asterisk (*) indicates significant differences from the untreated control strain (p < 0.05).