Figure 1.

Functional similarities between the Arabidopsis group I bZIP proteins. A, Signal patterns of the group I bZIP proteins fused to GFP. One-week-old transgenic plants expressing GFP alone or the VIP1-GFP, bZIP52-GFP, bZIP69-GFP, or bZIP30-GFP fusion protein were submerged in a hypotonic solution of 20 mm Tris-HCl, pH 6.8, and analyzed by fluorescence microscopy at the indicated time points to detect GFP signals in roots. For each line and time point, more than 10 plants were used, and representative images are shown. Bars = 100 μm. B, Gel-shift assay using the group I bZIP proteins. The GST-VIP1, GST-bZIP52, GST-PosF21, GST-bZIP69, GST-bZIP29, and GST-bZIP30 fusion proteins and GST alone were expressed in E. coli, purified, and used for a gel-shift assay with the digoxigenin-labeled CYP707A1 promoter fragment as the probe. The arrowhead indicates the position of the free probe. The experiments were performed three times, and a representative result is shown.