FIG. 2.

The classical secretory pathway is not required for the plasma membrane localization of GFP-Ras2p. (A) GFP-Ras2p was expressed from the galactose-inducible promoter of YEp55 in wild-type (LRB938), sec23-ts (LRB937), sec14-ts (LRB933), and sec9-ts (LRB934) strains. Cultures were grown at 24°C to mid-log phase, galactose (4%) was added, and cells were grown at 24°C (top) or 37°C (bottom) for 3 h. (B) Strains expressing GFP-Ras2(TMD) were treated as described for panel A, and images were captured by use of confocal microscopy 3 h after galactose addition. (C) Effect of brefeldin A on the subcellular localization of GFP-Ras2p and GFP-Ras2(TMD). GFP-Ras2p (top) or GFP-Ras2(TMD) (bottom) was expressed by galactose induction in RJY1538, and cultures were treated with dimethyl sulfoxide (untreated) or 50 μg of brefeldin A/ml in dimethyl sulfoxide (BFA).