Fig. S1.

(A) Mutation of AuxRE sites in the IAA19 promoter abolishes ARF19 activity. Red asterisks indicate location of G→A mutations introduced into the 300 bp native IAA19 promoter sequence used for reporter constructs. (B) All ARFs tested are expressed in yeast at least as well as ARF19. Expression of YFP:ARF fusion constructs is shown compared with yeast strains expressing no YFP (0) or YFP alone. The mean from three replicates is shown, with error bars representing SD. (C) All activator ARFs are effective activators of a synthetic promoter containing five direct AuxRE repeats spaced by five base pairs [DR5(5×)]. Fluorescence was measured by flow cytometry. Each yeast strain differs only by the ARF expressed (2, 5, 6, 8, 7, or 19). 0 indicates absence of an ARF transcription factor.