Fig. 4

Schematic diagram of the flavonoid pathway related to flower pigmentation in the Rhododendron sanguineum complex. Enzyme acronyms, expression patterns, and qRT-PCR results are shown beside each metabolic step and direction of synthesis marked with red arrows. The RNA-seq expression pattern of each gene is shown in heatmaps. The color scale represents log2-transformed FPKM (fragments per kilobase of exon per million mapped reads) values. Red represents high expression, and blue represents low expression. RsS, RsH, RsD represent R. sanguineum var. sanguineum, R. var. haemaleum, and R. var. didymoides, respectively. qRT-PCR expression results of the anthocyanin genes of the three varieties given as bar charts and shown as means of three biological replicates with standard errors. Analyses were performed on the flower bud samples. Relative mRNA (y-axis) expression levels were normalized to GAPDH (FN552706)