FIG. 4.

The YRR1 regulation network is linked to the PDR network. All the regulated genes found to be activated by Yrr1p fall into the three main characterized functional groups: MFS permease, ABC transporter, and metabolic genes. For all these genes, the consensus PDRE sequence is shown as an open circle. The promoters of the underlined genes gave positive results in the EMSAs presented above. Most of these genes are also regulated by Pdr1p, Pdr3p, and Yap1p. These transcription factors control the expression of other transcription factors in this series (dotted arrows) or, in some cases, their own expression (YRR1 and PDR3). Finally, the most common drugs used (4-NQO and oligomycin) are marked next to the genes associated with specific resistance.