Fig. 3.
AvrXa27 binds specifically to the Xa27 promoter. (A) Probes derived from Xa27, xa27, and Bs3 promoters used in EMSAs. Numbering is relative to the transcription start site (TSS). The polymorphisms between the Xa27 and xa27 promoter are shown by white letters and black background. The UPTAvrXa27 box of the Xa27 and the UPTAvrBs3 box of the Bs3 promoter are underlined (B) AvrXa27 binds with high and low affinity to the Xa27 and xa27 promoters, respectively. EMSA with AvrXa27 and Xa27- or xa27-derived probes and competition experiment between AvrXa27 and different amounts (in fmol) of a nonlabeled competitor probe in a 6% nondenaturing polyacrylamide gel. Positions of the bound and free probe are indicated on the left. (C) AvrXa27 and AvrBs3 bind specifically to the Xa27 and Bs3 promoters, respectively. EMSA with AvrBs3 and AvrXa27 and Xa27- and Bs3-derived probes in a 6% nondenaturing polyacrylamide gel. Protein amounts are in fmol. Positions of the bound and free probe are indicated on the left.