Fig. 6. Deletion of the STE20 gene in cells which are defective for the SLN1 branch of the HOG pathway (in this case, ssk2Δ ssk22Δ double mutant) leads to osmosensitivity with galactose but not dextrose, as the sole carbon source. Wild-type strain TM141 (WT), and mutant strains FP58 (ste20Δ), TM252 (ssk2Δ ssk22Δ) and DR76 (ssk2Δ ssk22Δ ste20Δ) were streaked onto rich media containing 2% glucose (YPD) or 2% galactose (YPGal) with or without 1.5 M sorbitol.