Fig. 6

LlC3H18 binds the promoter of LlWRKY33 and activates its expression. A Detection of the expression level of LlWRKY33 in LlC3H18-overexpressed lily petals. Data are presented as the mean ± SD of three replicates (Student’s t-test, * P < 0.05). B Detection of the expression level of LlWRKY33 in LlC3H18-silencing lily petals. Data are presented as the mean ± SD of three replicates (Student’s t-test, * P < 0.05). C Diagram of the LlWRKY33 promoter. The W-box elements are marked with blue triangles. The truncated fragments used for the yeast one-hybrid (Y1H) assay are marked with black lines. The mutant fragment used for the Y1H assay is marked with a red line. D A Y1H assay for LlC3H18 and the promoter of LlWRKY33. Fragment activity was analyzed by a color change on Ura-/Trp-deficient SD medium following the addition of x-gal. One representative image based on three replicates. E An electrophoretic mobility shift assay (EMSA) of GST-LlC3H18 and the potential elements from the LlWRKY33 promoter. One representative image based on three replicates. F Constructs used in the dual-luciferase reporter assay. G Detection of the LUC signal in tobacco leaves. One representative image based on three replicates. Scale bar = 1 cm. H Measurement of LUC intensity in the dual-luciferase reporter assay. Data are presented as means ± SD of three replicates (Student’s t-test, * P < 0.05). (I) Detection of LlWRKY33 expression in the LlWRKY33-overexpressed petal discs. Data are presented as the mean ± SD of three replicates (Student’s t-test, * P < 0.05). (J) Phenotypes of lily petal discs under room temperature conditions (RT, 22 °C) and after exposure to heat stress (HS, 40 °C, 12 h). Representative image came from three experiments. Scale bar = 1 cm. (K) Relative ion leakage (%) of discs at 22 °C (RT) and after HS (40 °C, 12 h). Data are presented as the mean ± SD of three replicates (Student’s t-test, * P < 0.05; ND, no significant difference; the SK-LlWRKY33 was compared with the SK-II control under the RT or HS condition, respectively