Epigenetic and Conventional Regulation Is Distributed among Activators of FLO11 Allowing Tuning of Population-Level Heterogeneity in Its Expression
Figure 6
Ethanol modulates silencing at the promoter via Flo8p.
(A) Wildtype grown in SD complete with ethanol added to final concentration ranging between 0 and 3%. (B) Activators titrated in wildtype background in SD ura- +1% ethanol. All responses are graded, suggesting loss of silencing at the promoter. (C) Synthetic activator (rtTA) titration in SD ura- +1% ethanol. As in (B), responses are also graded. (D) Activators titrated in flo8Δ in SD ura- +1% ethanol. The response is closer to that in Figure 4A rather than Figure 6B, indicating that ethanol abolishes silencing at the promoter through Flo8p. (E) Representative fluorescence histograms of titrations shown in (A, B, C, D). (Top) Wildtype titrated as in panel A, Tec1p titrated as in (B), and as in (D). (Bottom) rtTA titrated in strain with tetO site at −1160 (occluding Sfl1p binding site), and at −350 (nucleosome occluded site) as in panel C; Msn1p titrated as in (D).