Figure 4.

Overexpression of FLO11 in diploids growing on rich media enables them to invade agar. A diploid strain (YSL1015) was transformed with either the vector control pRS425 (first row of colonies) or with a multicopy plasmid carrying FLO11, pYSL12 (middle row of colonies). Invasive growth is compared with that of a wild-type isogeneic haploid strain, L5487 (bottom row of colonies). Cells were patched onto YEPD medium and grown for 3 d at 30°C followed by 2 d of growth at room temperature. (A) The total growth on the surface of the agar, shown before the plate was rinsed with water. (B) The same plate after rinsing cells off the surface of the agar with a gentle stream of deionized water. Invasive growth is demonstrated by cells that remain in the agar.