Genetic analysis of the role of Yak1p in
regulating pseudohyphal growth. Wild-type diploid yeast (MLY61 a/α)
or yeast disrupted for YAK1 (DSY1 a/α) were
transformed with a control vector (A), or with vectors expressing
RAS2VAL19 (B), STE11-4 (C),
STE12 (D), TEC1 (E), TPK2
(F), PHD1 (G), or the C terminus of E1A (H). Transformed
cells were then transferred to SLAD plates, allowed to grow for 2
d at 30°C, and photographed.