FIG. 4.
Atg13-8SA induces autophagy in normally grown cells. (A) Pho8Δ60-expressing (OND88) and YYK757 (atg2Δ) cells harboring the indicated p416GAL1[ATG13] plasmids were grown in SCRaf and shifted to SCRafGal. Alkaline phosphatase (ALP) activity (U, solid line) and cell growth (OD600, broken line) were monitored. (B) Pho8Δ60-expressing cells harboring the p306GAL1[ATG13-8SA] plasmid were subjected to the ALP assay before or after a 4-h incubation with SCRafGal or a 4-h incubation with nitrogen-depleted medium [SRaf(−N)]. The ALP activity of each sample is shown. Error bars represent the standard deviations [SD] from three independent experiments. (C) Accumulation of autophagic bodies. Cells used for panel A were incubated in SCRafGal in the presence of 1 mM PMSF (to inhibit degradation of autophagic bodies) for 6 h. Autophagic bodies were visualized by phase-contrast microscopy. (D) Electron microscopy of cells used for panel B. Bar, 1 μm.