The bZIP domain of GBF1 interacts with full-length HY5 and HYH proteins. In A–H, a shows GFP channel fluorescence produced by GFP of pCAMBIA-1302 vector, serving as a control of transformation; b shows the YFP channel image produced by reconstruction of YFP; c shows the respective bright field image; and d shows a merged image of a, b, and c. A and B, full-length GBF1 (fused to YFPN-ter) and domains of HY5 (fused to YFPC-ter) co-expressed in onion epidermal cells along with GFP. C and D, full-length GBF1 (fused to YFPC-ter) and domains of HYH (fused to YFPN-ter) co-expressed in onion epidermal cells along with GFP. E and F, full-length HY5 (fused to YFPC-ter) and domains of GBF1 (fused to YFPN-ter) co-expressed in onion epidermal cells along with GFP. G and H, full-length HYH (fused to YFPN-ter) and domains of GBF1 (fused to YFPC-ter) co-expressed in onion epidermal cells along with GFP.