Genetic mapping and characterization of the globe artichoke (+)-germacrene A synthase gene, encoding the first dedicated enzyme for biosynthesis of the bitter sesquiterpene lactone cynaropicrin

► We investigated the accumulation of cynaropicrin in different tissues of globe artichoke. ► A germacrene A synthase (GAS) was identified and characterized. ► Expression of GAS paralleled accumulation of cynaropicrin. ► A sequence polymorphism within a mapping population parent allowed the GAS locus to be positioned on a genetic map.