Class I but not Class III <i>sob</i> alleles in the <i>P</i>_{<i>fla/che</i>} promoter region increase <i>P</i>_{<i>fla/che</i>} expression.

<p>β-galactosidase assays of <i>lacZ</i> gene expression under the control of WT (open bars), Class I <i>sob21</i> (gray bars), or Class III <i>sob6</i> (black bars) <i>P</i>_{<i>fla/che</i>} promoter regions. Each reporter was expressed in either WT, <i>swrB</i>, or <i>swrA</i> mutant backgrounds as indicated. The following strains were used to generate this panel: <i>amyE</i>::<i>P</i>_{<i>flache</i>}^<i>WT</i><i>-lacZ</i> (DS793), <i>amyE</i>::<i>P</i>_{<i>flache</i>}^<i>sob21</i><i>-lacZ</i> (DS1426), <i>amyE</i>::<i>P</i>_{<i>flache</i>}^<i>sob6</i><i>-lacZ</i> (DS9120), <i>swrB amyE</i>::<i>P</i>_{<i>flache</i>}^<i>WT</i><i>-lacZ</i> (DK285), <i>swrB amyE</i>::<i>P</i>_{<i>flache</i>}^<i>sob21</i><i>-lacZ</i> (DK1130), <i>swrB amyE</i>::<i>P</i>_{<i>flache</i>}^<i>sob6</i><i>-lacZ</i> (DK1117), <i>swrA amyE</i>::<i>P</i>_{<i>flache</i>}^<i>WT</i><i>-lacZ</i> (DK284), <i>swrA amyE</i>::<i>P</i>_{<i>flache</i>}^<i>sob21</i><i>-lacZ</i> (DK1129), <i>swrA amyE</i>::<i>P</i>_{<i>flache</i>}^<i>sob6</i><i>-lacZ</i> (DK1116). Error bars are the standard deviations of three replicates. β-galactosidase values presented in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1005443#pgen.1005443.s010" target="_blank">S4 Table</a>.