Figure 5.

CgMYB1 positively controls phenylpropanoid metabolism. A Correlation network for structural genes of the phenylpropanoid biosynthesis pathway and CgMYB1. Pearson correlation coefficient values were calculated for each pair of genes. Genes in phenylpropanoid biosynthesis are shown as follows: PAL, phenylalanine ammonia lyase; CHI, chalcone isomerase; CHS, chalcone synthase; C4H, cinnamate 4-hydroxylase; FLS, flavonol synthase; 4CL, 4-coumarate CoA ligase. B A dual luciferase reporter assay in Nicotiana benthamiana revealed that CgMYB1 can activate the promoters of the tested genes. LUC activity was normalized to REN activity as an internal control. Error bars indicate standard deviations (SDs) from three replicates. Asterisks indicate significant differences as determined by t-tests (P < 0.05). C Binding tests for CgMYB1 to the promoters of tested genes in a yeast one-hybrid assay. Each of the promoters was fused to a His2 reporter, and CgMYB1 was fused to GAL4 AD. D Relative expression analysis of endogenous phenylpropanoid biosynthesis genes in CgMYB1-overexpressed tomato lines based on quantitative RT-PCR. Data are means ±SDs of two independent biological replicates. Asterisks (P < 0.05, Student’s t-tests) indicate significant differences compared with the WT (wild type). E The flavonoid content in leaves from CgMYB1-OX transgenic tomato plants. The data are presented as means ±SDs, n = 3. Expression data were Z-score standardized.