Figure 3.

Increased synthesis of chitin in response to tunicamycin exposure is not essential for ER stress tolerance. (A) Exponentially growing cells of the BY4741 wild-type (wt), slt2, chs3, and slt2 chs3 mutant strains were treated with 11.5 mM glucosamine (GlcN) and/or 2 μg/mL tunicamycin (Tn) for 90 min and processed for chitin staining with calcofluor white (CFW) and microscopy visualization as described in the Materials and Methods section. (B) The same strains were checked for growth in YPD medium lacking or containing tunicamycin at the indicated concentrations (μg/mL). Cultures were diluted and spotted as indicated in Figure 1. In all cases, representative experiments are shown.