Fig. 1. Septins contribute to shaping the wide necks in cdc42^V36T,K94E mutants and the base of the bud in wild-type cells. (A) Strains DLY3067 (GAL1p-CDC42) and DLY4412 (cdc12-6 GAL1p-CDC42) were transformed with pMOSB55 (CDC42) or pMOSB57 (cdc42^V36T,K94E). Cells were photographed after growth to exponential phase at 24°C, the permissive temperature for cdc12-6 mutants, on dextrose-containing medium. (B) The same strains were grown to stationary phase, stained with FITC-ConA to visualize cell wall mannan, washed, and inoculated into fresh medium at 37°C, the restrictive temperature for cdc12-6 mutants. Morphology of new buds (unstained by FITC-ConA) was documented 3 hours later. Bar, 10 µm. (C) Strains DLY4035 (GAL1p-SWE1) and DLY7452 (cdc12-6 GAL1p-SWE1) were grown to stationary phase in raffinose-containing medium at 24°C, and inoculated into galactose-containing medium (to induce Swe1p expression) at 37°C (to inactivate septins). Cell morphology was documented 5 hours later. Bar, 5 µm.