Gene expression in the flavonoid pathways and flavanols in leaves of purple tea ZJ and green tea YK. (a) The differentially expressed genes (DEGs) in flavonoid biosynthesis pathway, modified from KEGG map00941 and Shi et al. published review in 2014. The enzyme framed in a small box catalyzes the reaction. C4H: cinnamic acid 4-hydroxylase, CHS: chalcone synthase, F3H: flavanone 3-hydroxylase, DFR: dihydroflavanol 4-reductase, ANR: anthocyanidin reductase, UFGT: UDP-glucose: flavonoid 3-O-glucosyltransferase; (b) the expression levels in three tissues in tea cultivar ZJ and YK. The heatmap represents the Z-score of each gene expression after the log2 (FPKM) transformation. Suffix _b, _1 and _2 represent the bud, the 1st leaf immediately next to the bud and the 2nd leaf immediately next to the 1st leaf; (c) the comparison of DEG gene UFGT expression between two tea cultivars; (d) the UFGT abundance via RT-qPCR in six leafy tissues developed sequentially and letters above the bar represent the statistical significance from Duncan’s multiple range test (p < 0.05); (e) the contents of flavanols in the catechin category.