Figure 5. The region between Y337 and F343 is crucial for Pbs2-independent phosphorylation and activation of Hog1, but is dispensable for Pbs2-dependent Hog1’s biological activity.

A. hog1Δ cells harboring either an empty vector (negative growth control), a vector expressing intrinsically active Hog1^D170A, vectors expressing Hog1^WT, or a vector expressing Hog1 missing the amino acids between Y337 and F343 (Hog1^{(Y337–F343)Δ}) were plated on plates containing YPD supplemented with 1 M NaCl. All strains were also plated on medium with no NaCl and all grew equally well on these plates (not shown). B. Phosphorylation levels of Hog1^WT, Hog1^D170A and Hog1^{(Y337–F343)Δ} were tested when expressed in hog1Δ cell. C. hog1Δpbs2Δ cells harboring same plasmids as in A were plated on plates containing YPD supplemented with 0.8 M NaCl. hog1Δpbs2Δ cells expressing the intrinsically active Hog1^D170A served as a positive control. All strains were also plated on medium with no NaCl and all grew equally well on these plates (not shown). D. Phosphorylation levels of Hog1^WT, Hog1^D170A and Hog1^{(Y337–F343)Δ} were tested when expressed in hog1Δpbs2Δ cells.