FIG. 7.

rop1 is dispensable for prf1 gene expression and fungal development on the plant surface. All strains carried one copy of a transcriptional prf1 promoter-gfp fusion (Pprf1::gfp) integrated into the ip locus. (A) The FB2 (a2 b2)-derived strains are indicated on top; they were stimulated with compatible a1 pheromone for 5 h (lower panel) or treated with dimethyl sulfoxide for the same period of time (upper panel). The right panels show GFP fluorescence of the same cells depicted on the left. All pictures were taken with the same magnification. Bar, 4 μm. (B) Mixtures of compatible wild-type (wt) or compatible Δrop1 strains carrying the reporter (Pprf1::gfp) were spotted on charcoal-containing PD plates. The cell mixtures indicated on top were microscoped after 1 day of incubation. Lower panels show GFP fluorescence of the differential interference contrast-visualized cells depicted in the upper panels. All pictures were taken at the same magnification. Bar, 20 μm. (C and D) Mixtures of compatible strains at various stages of development (sporidia, conjugation hyphae, matings, and appressoria) on the plant surface. (C) Wild-type strains. (D) Δrop1 mutants. Pictures were taken as indicated on the right with a DAPI filter after Calcofluor staining (upper panels) or a GFP filter to visualize reporter gene expression (lower panels). All pictures were taken at the same magnification. Bar, 4 μm.