FIG 4.

CYS-3 directly regulates genes involved in sulfur acquisition and metabolism. (A) Plot built with Circos version 0.69 (51) to display genes activated in response to sulfur starvation and/or by CYS-3. Green lines indicate genes that were expressed at least 2-fold higher in wild-type cells exposed to sulfur starvation than 24 μM sulfate. Blue lines indicate genes that were expressed at least 2-fold higher in wild-type than cys-3⁻ cells exposed to sulfur starvation. Red lines indicate genes whose promoters were bound and whose expression was activated by CYS-3 in response to sulfur starvation. In this plot, all 62 genes whose promoters were bound by CYS-3 were activated by CYS-3, and 56 genes whose promoters were bound by CYS-3 were also activated in response to sulfur starvation. Of the 136 genes that were activated in response to sulfur starvation, 114 were activated by CYS-3. (B) CYS-3 consensus DNA binding motif (E value = 2.9 × 10⁻³⁹) built using MEME version 5.1.1 (48).