Metabolons and the biosynthesis of Gerbera hybrida flavonoids

The formation of protein complexes, metabolons, and the channeling of intermediates of secondary metabolism has been discussed for at least 30 years. Metabolons and channeling enable plants to perform a highly effective synthesis of specific natural products without or with reduced metabolic interference and avoiding accumulation of toxic intermediates. In spite of a long tradition of the concept, precise examples of complete metabolons are very scarce. Our aim is to define flavone and anthocyanidin specific metabolons in the ornamental plant Gerbera hybrida. Our earlier data shows that specific genes are expressed early in development PAL and CHS3 and others late PAL, CHS1 and DFR, possibly correlating with flavone and anthocyanin biosynthesis. Furthermore, transformation of the pelargonidin type Gerbera cultivar Terra Regina with a MYB-type regulatory gene induces cyanidin biosynthesis without interfering with the background pelargonidin biosynthesis. Using our large set of EST, the expanding genomic sequence resource of Gerbera and new data from Illumina sequences for wild type of Regina and MYB transgenic lines, we are establishing correlations in expression and patterns of protein-protein interactions for the whole flavonoid metabolism isoenzyme complex in our model plant.