Figure 5.
Identification of transcription factors regulating PcgalE1, a key polysaccharide biosynthesis gene, by dual-luciferase and Y1H assays. (A) Identification of transcription factors activating the promoter of PcgalE1 by dual-luciferase assay. The LUC/REN value of the promoter’s empty vector was set as 1 as a calibrator. Each value represents the mean ± SD of three independent experiments. (B) The bait fragments used to construct the reporter vectors in the Y1H assay. (C) The bait fragments with W-box mutants used to construct the reporter vectors in the Y1H assay. (D) Interaction of WRKY31 and WRKY34 with a promoter fragment of PcgalE1 and its mutated sequence in Y1H assays. Yeast was cultured on Leu-lacking SD medium with or without 200 ng mL −1 of Aureobasidin A (AbA) at 30 °C for 72 h. (E) A hypothetical model of PCP biosynthesis regulated by PcWRKY31 and PcWRKY34 in two Polygonatum cyrtonema germplasms.