Figure 4. Cultivation in low-glucose medium extends chronological lifespan under glucose starvation in a Wee1-dependent manner.

(A,B) Time course of changes in viability of cells cultivated in glucose-depleted medium. WT (open circles) or wee1Δ (crosses) cells grown in high-glucose (111 mM) medium were transferred to medium lacking glucose directly (A) or after 1-day incubation in low-glucose (4.4 mM) medium (B). Aliquots of the cell culture were taken at the indicated time points and viability was determined by measuring the proportion of cells forming colonies on solid YES medium. (C) Passage of transient G2-arrest period in low glucose is essential for extension of lifespan under conditions of glucose starvation. The experimental procedure is illustrated in the upper panel. The WT cells grown in high-glucose (111 mM) medium were transferred to and cultivated in low-glucose (4.4 mM) medium for 0, 0.5, 3, 6 or 12 hours, and then transferred to medium without glucose. Cell viability was measured after 7-day incubation in glucose-depleted medium. The averages of three independent experiments are shown. The bars indicate ±SD.