Fig. 4.

The effect of hypoxia on the activity of unfolded protein response element (UPRE)-driven reporters in the parent BY4741 and knockout strains. A: the effect of hypoxia on the activity of the UPRE-1-driven reporter. B: the effect of hypoxia on the activity of the UPRE-2-driven reporter. C: the effect of hypoxia on the activity of the UPRE-3-driven reporter. The parent BY4741, Δrai1, Δrpl20a, Δrsm22, Δnsr1, and Δbud21 cells bearing a UPRE-driven reporter were grown in air or in a hypoxia chamber. Cells were collected, and β-galactosidase activities (in Miller units) were measured and plotted here. Data shown here are averages of data from at least three independent cultures. Welch 2-sample t-tests were performed to compare hypoxic with normoxic wild-type or mutant cells. The P values were calculated by using the R program. *P values of < 0.005; **P values of < 0.001.