CPTA Modulates Levels of Carotenogenic Proteins and their mRNAs and Affects Carotenoid and ABA Content as well as Chromoplast Structure in Narcissus pseudonarcissus Flowers

摘要: : To investigate mechanisms leading to enhanced carotenoid formation, daffodil (Narcissus pseudonarcissus) flowers were treated with the lycopene cyclase (LYC) inhibitor CPTA. Under these conditions, chromoplasts underwent strong morphological changes and accumulated was found sequestered in crystals. During this process total content increased about 2-fold. This increase accompanied by an upregulation of transcript levels phytoene synthase (PSY), desaturase (PDS) (LYC). In contrast, η-carotene (ZDS) not a target for CPTA-induced upregulation, although its product accumulated. At protein level, CPTA induction carotenogenic enzymes also observed, again exception ZDS. Lycopene accumulation, caused treatment, decrease β-carotene derivatives, especially zeaxanthin. Our data suggest that biosynthesis may undergo end-product regulation via effector probably originating from derivative. Increased concentrations abscisic acid (ABA) measured after treatment be involved regulatory phenomenon, pointing presence additional xanthophyll-independent source phytohormone.