Deletion of the PIISIQ motif affects Crz1p localization. (A) WT (ASY472) cells expressing 3xGFP–Crz1p (LMB127), 3xGFP–Crz1pΔ311–340 (LMB230), 3xGFP–Crz1pΔPIISIQ (LMB231), or GFP vector were grown to log phase at 21°C. Cells were treated with 200 mM CaCl2 for 10 min and visualized with fluorescence microscopy. Bar, 20 μm. (B) The PIISIQ motif is required for complementation of a crz1Δ strain. ASY472 cells expressing LMB127, LMB230, LMB231, or GFP vector were plated on selective media with or without 350 mM LiCl2 and grown at 30°C for 3 d. (C) Deletion of the PIISIQ motif affects Crz1p activity. β-Galactosidase activity was measured in crz1Δ cells harboring an integrated CDRE::lacZ reporter (ASY834). Strains expressed LMB127, LMB230, or LMB231 and were treated with (open bars) or without (black bars) 100 mM CaCl2. The numbers are the result of two replicates analyzed in triplicate, and the standard deviation is the error between samples.