FIG. 3.

Quantification of different cell morphologies under standard (YPD medium) and filamentation-inducing (YPD medium plus 10% serum) growth conditions. Cultures of wild-type (WT; RBY1132), KAR3/Δkar3 (RSY8), Δkar3/Δkar3 (RSY11), and Δkar3/Δkar3+KAR3 (RSY26) cells were incubated for 6 h in YPD medium at 30°C or in YPD medium plus 10% serum at 37°C. A total of 3,001 cells were assessed for morphology and classified as budding yeast, pseudohyphae, and hyphae, and the results are expressed as percentages in pie charts. A statistically significant difference in the percentage of cells forming hyphae was observed between the wild-type strain and either the Δkar3/Δkar3+KAR3 strain or the Δkar3/Δkar3 strain (P < 0.005). Note that cells within germ tubes or within chains of pseudohyphal cells were counted as distinct cells.