Multigenome analysis implicates miniature inverted-repeat transposable elements (MITEs) in metabolic diversification in eudicots

Recently discovered biosynthetic gene clusters in plants are a striking example of the nonrandom complex structure of eukaryotic genomes. The mechanisms underpinning the formation of these clustered pathways are not understood. Here we carry out a systematic analysis of transposable elements associated with clustered terpene biosynthetic genes in plant genomes, and find evidence to suggest a role for miniature inverted-repeat transposable elements in cluster formation in eudicots. Our analyses provide insights into potential mechanisms of cluster assembly. They also shed light on the emergence of a "block" mechanism for the foundation of new terpene clusters in the eudicots in which microsyntenic blocks of terpene synthase and cytochrome P450 gene pairs duplicate, providing templates for the evolution of new pathways.