Suppression of the phytoene synthase gene (EgcrtB) alters carotenoid content and intracellular structure of Euglena gracilis.

Our results indicate that suppression of EgcrtB causes a significant decrease in carotenoid and chlorophyll content in E. gracilis accompanied by changes in intracellular structures, suggesting that Dtx (de-epoxidized form of diadinoxanthin cycle pigments) contributes to photoprotection of this alga during the long-term acclimation to light-induced stress.