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Globe artichoke (Cynara cardunculus var. scolymus) belongs to the Asteraceae family, in which one ofthe most biologically significant class of secondary metabolites are sesquiterpene lactones (STLs). Inglobe artichoke the principal STL is the cynaropicrin, which contributes to approximately 80% of itscharacteristic bitter taste. Cynaropicrin content was assessed in globe artichoke tissues and was observedto accumulate in leaves of different developmental stages. In the receptacle, a progressive decrease wasobserved during inflorescence development, while the STL could not be detected in the inflorescencebracts. Almost undetectable amounts were found in the roots and inflorescence stems at the commercialstage. Cynaropicrin content was found to correlate with expression of genes encoding CcGAS, CcGAO andCcCOS, which are involved in the STL biosynthesis.A more detailed study of leaf material revealed that cynaropicrin predominantly accumulates in thetrichomes, and not in the apoplastic cavity fluids. Analysis of the promoter regions of CcGAO and CcCOSrevealed the presence of L1-box motifs, which confers trichome-specific expression in Arabidopsis, sug-gesting that cynaropicrin is not only stored but also synthesized in trichomes. A transient expression ofGFP fusion proteins was performed in Nicotiana benthamiana plants: the CcGAS fluorescence signal waslocated in the cytoplasm while the CcGAO and CcCOS localized to the endoplasmatic reticulum.