Biosynthesis and localization of parthenolide in glandular trichomes of feverfew (Tanacetum parthenium L. Schulz Bip.)

► Tanacetum parthenium is an important medicinal plant accumulating parthenolide. ► The gene encoding germacrene A synthase (TpGAS) was cloned and expressed. ► The highest expression of TpGAS was observed in glandular trichomes. ► Glandular trichomes contain the highest concentration of parthenolide. ► Biosynthesis of parthenolide is developmentally regulated in feverfew.