Fig. 3.

Increasing the frequency of switching incrementally by increasing the level of expression of WOR1, the master switch gene, incrementally, causes incremental increases in biofilm parameters of a same-sex a/a white cell biofilm, until the proportion of opaque cells, which do not form biofilms, interferes. The wor1/wor1 mutant was transformed with WOR1 under the regulation of a tetracycline (doxycycline)-controlled promoter, generating the wor1-wor1-TETp-WOR1 strain. The biofilms were then treated with increasing concentrations of the inducer doxycycline. (A) Percentage of opaque cell formation in a 48-h biofilm as a function of doxycycline concentration, as assessed by plating experiments. (B) WOR1 expression as a function of doxycycline concentration, as assessed by RT-PCR. ACT1 expression levels are included as a loading control. (C) Biomass of biofilms as a function of doxycycline concentration. (D) Thickness of biofilms as a function of doxycycline concentration. (E) β-Glucan released into the supernatant as a function of doxycycline concentration. The mean percentage of opaque cells measured by plating experiments is provided at the bottom of panels C through E. The data from three-independent experiments were pooled and analyzed for the data in panels A and C through E. Error bars represent standard deviations.