Figure 3.

Hog1 phosphorylation in WT and ∆rtg2 mutants. (a) Cells were grown up to exponential phase (U), incubated at low pH, and (b) treated with acetic acid (AcOH). Cell protein extracts were prepared from WT and ∆rtg2 cells at the indicated times and analyzed by immunoblot with anti-P-Hog1p and anti-Hog1p antibodies. Cell extracts from ∆hog1 and ∆hog1∆rtg2 cells have been analyzed as a negative control. Ponceau staining was used as loading control. The histogram reports the ratio between phosphorylated (P-Hog1) and total Hog1 as quantified by densitometric analysis of the film normalized with Ponceau staining and expressed in arbitrary units. Reported values are the means ± standard deviations of three independent experiments. Paired Student's t-test: statistically significantly different with ^∗∗p < 0.05 and ^∗p < 0.1 when comparing Δrtg2 versus WT under acid stress.