FIG. 3.

Expression and cellular localization of GFP-PMK1 during appressorium formation in transformant Xh14. (A) Xh14 conidia germinated on glass coverslips were removed at indicated times and examined under differential interference contrast (left panels) and epifluorescence microscopy (right panels). Fluorescence was observed in the conidia and germ tubes at the early time points, such as 2 or 4 h. By 12 h, the majority of the GFP signal was observed in appressoria. At 24 h, conidial cells exhibited no GFP signal or only a very weak GFP signal. (B) The GFP-Pmk1 signal localized to the nucleus in appressoria. A conidium of Xh14 incubated on a glass coverslip for 24 h was stained with Calcofluor and Hoechst 33258 (middle panel) to visualize cell walls and nuclei (arrow). GFP signal (right panel) appeared to be concentrated in the appressorium at the position of the nucleus. Bar = 10 μm.