Phenylpropanoid polyamine conjugate biosynthesis in Arabidopsis thaliana flower buds

The presence of phenylpropanoid polyamine conjugates is a characteristic feature in flowers of many plant species. In this report we annotate a set of genes with an effect on the polyamine phenylpropanoid conjugate quantity and pattern in young flower buds of A. thaliana, identify a set of hydroxycinnamoyl spermidine conjugates in several insertion lines, different from the pattern observed in wild type plants, and propose a biosynthetic pathway for phenylpropanoid polyamine conjugate formation. Surprisingly, transcript suppression of the genes early in the pathway was observed in knockout or RNAi-lines of the genes encoding late enzymatic steps.