Figure 1.

Phenotype of yeast cells lacking the Cdc42 GAPs Rga2 and Bem3. Mutants lacking Rga2 form elongated cells (C) in a Swe1-independent manner (E). Elongation is not enhanced by deletion of RDI1 (F). Septin rings form at the bud neck (green), except for some bem3Δ/Δ rga2Δ/Δ mutants cells that show ectopic septin rings located distal to an elongated bud lacking a constriction at its neck and proximal to a bud showing isotropic growth (arrowed in D). Yeast cells of the indicated genotype were grown for 2.5 h after inoculation of an overnight culture into YEPD at 25°C to promote yeast growth. Cells were counterstained with calcofluor white (blue) and examined with a Delta Vision microscope. Bars, 5 μm.