MdFLP Protein-DNA Interaction Analysis

EMSA was conducted according to Xie et al. [40 (link)]. MdFLP was inserted into the pGEX4T-1 plasmid. The MdFLP-GST plasmid was expressed in BL21 and purified using glutathione Sepharose beads. Three oligonucleotide probes of the MdPIN3 and MdPIN10 promoters were labeled using an EMSA probe biotin labeling kit (Beyotime). The mutant probes were labeled and contained one mutated nucleotide. The EMSAs were conducted following the manufacturer’s instructions (Thermo Scientific). The binding specificity was also examined by competition with a fold excess of unlabeled oligonucleotides. The primers used for EMSA are listed in Additional file 2: Table S1.