Differential gene expression profiles of red and green forms of Perilla frutescens leading to comprehensive identification of anthocyanin biosynthetic genes

Differential screening by PCR-select subtraction was carried out for cDNAs from leaves of red and green perilla, two chemovarietal forms of Perilla frutescens regarding anthocyanin accumulation. One hundred and twenty cDNA fragments were selected as the clones preferentially expressed in anthocyanin-accumulating red perilla over the nonaccumulating green perilla. About half of them were the cDNAs encoding the proteins related presumably to phenylpropanoid-derived metabolism. The cDNAs encoding glutathione S-transferase (GST), PfGST1, and chalcone isomerase (CHI), PfCHI1, were further characterized. The expression of PfGST1 in an Arabidopsis thaliana tt19 mutant lacking the GST-like gene involved in vacuole transport of anthocyanin rescued the lesion of anthocyanin accumulation in tt19, indicating a function of PfGST1 in vacuole sequestration of anthocyanin in perilla. The recombinant PfCHI1 could stereospecifically convert naringenin chalcone to (2S)-naringenin. PfGST1 and PfCHI1 were preferentially expressed in the leaves of red perilla, agreeing with the accumulation of anthocyanin and expression of other previously identified genes for anthocyanin biosynthesis. These results suggest that the genes of the whole anthocyanin biosynthetic pathway are regulated in a coordinated manner in perilla.