WRKY45 binds to the PHT1;1 promoter. A, Diagram of the PHT1;1 promoter region showing the relative positions of the W-boxes. The W-boxes are marked by gray rectangles, and relative positions and sizes of the different PCR-amplified fragments are indicated by black lines under the W-box(es). B, Western-blot analysis was performed with anti-Myc to detect the WRKY45-Myc protein in the WRKY45-Myc transgenic line and wild-type seedlings. C, ChIP analysis to detect the association between WRKY45 and the W-boxes within the PHT1;1 promoter in the WRKY45-Myc transgenic line. The ChIP signals with (anti-Myc) and without (NoAB) addition of anti-Myc are indicated. D, EMSA assay to analyze the binding of WRKY45 to PHT1;1 promoter. Each biotin-labeled DNA probe was incubated with WRKY45-CKS protein. An excess of unlabeled probes was added to compete with labeled promoter sequences. Biotin-labeled probes incubated with CKS protein served as the negative control. WT, Wild type.