Metabolic engineering to simultaneously activate anthocyanin and proanthocyanidin biosynthetic pathways in Nicotiana spp.
(A) Some of the in vitro regenerated transgenic calli showed an intense purple pigmentation due to accumulation of anthocyanins. (B) In vitro regenerated control plantlet. (C) In vitro regenerated transgenic tobacco plant showing intense purple color in all tissues. (D) Control plant after acclimation in the greenhouse. (E) Transgenic tobacco plant Nt#7 with intense purple pigmentation after acclimation in the greenhouse. (F) Detail of a leaf from the transgenic plant Nt#7 showing intense purple pigmentation in the abaxial side and vascular bundles. (G) Detail of a leaf from the trasngenic plant Nt#5 showing only small patches of purple pigmentation. (H) Entire and disected flower from a control (left) and transgenic plant Nt#7 (right). (I) Carpel and stamens from a disected flower of a control (left) and the Nt#7 transgenic plant (right).