FIG 1.

The PI-4-kinase Stt4 is required for filamentous growth. (A) Strains (wild type, PY4861; stt4Δ/Δ, PY5111; stt4Δ/Δ+STT4, PY5131) were incubated with serum at 37°C for 90 and 120 min. Bar, 5 μm. (B) Percentages of filamentous cells were determined from three independent experiments (n ≥ 120 in each) with the abovementioned strains in addition to PY5757, an stt4Δ/Δ+stt4* strain encoding Stt4[G1810D]. Cells were considered filamentous if germ tubes were twice length of the mother cell or longer. Error bars indicate standard deviations (SD). (C) Stt4 is required for invasive filamentous growth. Strains were incubated for 4 days at 30°C on serum agar plates. Similar results were observed in three independent experiments.