FIG. 6.

Cell survival upon osmotic stress is reduced in hog1Δ and smp1Δ strains. To analyze the role of Smp1 in osmotic stress adaptation, we measured the incorporation of PI, as described in Material and Methods, as a measure of cell viability in wild-type, hog1Δ mutant, and smp1Δ mutant strains. Yeast cells were grown in YPD and subjected (open bars) or not subjected (filled bars) to an osmotic shock (1 M NaCl for 60 min). Viability was determined by the addition of PI and measurement of the percentage of PI-positive cells by using a flow cytometer. The results are the measurements in duplicate from six independent experiments. The data were confirmed by Phloxin B staining and visual microscopy (see Materials and Methods).