Evolution of Glucosinolate Diversity via Whole-Genome Duplications, Gene Rearrangements, and Substrate Promiscuity

Abstract

Over several decades, glucosinolates have become a model system for the study of specialized metabolic diversity in plants. The near-complete identification of biosynthetic enzymes, regulators, and transporters has provided support for the role of gene duplication and subsequent changes in gene expression, protein function, and substrate specificity as the evolutionary bases of glucosinolate diversity. Here, we provide examples of how whole-genome duplications, gene rearrangements, and substrate promiscuity potentiated the evolution of glucosinolate biosynthetic enzymes, regulators, and transporters by natural selection. This in turn may have led to the repeated evolution of glucosinolate metabolism and diversity in higher plants.

Keywords: gene conversion/fusion; gene/genome duplication; glucosinolates; neofunctionalization; substrate promiscuity.