Progress in the dissection and manipulation of vitamin E synthesis

• Published in: Trends in plant science Vol. 10; no. 12; pp. 574 - 579
• Main Author: DellaPenna, Dean
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2005; Elsevier
• Subjects: Arabidopsis - enzymology; Arabidopsis - metabolism; Arabidopsis - physiology; Arabidopsis thaliana; biochemical pathways; Biological and medical sciences; biosynthesis; Fundamental and applied biological sciences. Psychology; homogentisic acid; literature reviews; Metabolism; Metabolism. Physicochemical requirements; methyltransferases; Methyltransferases - metabolism; Photosynthesis; plant biochemistry; Plant physiology and development; Plants, Genetically Modified - enzymology; Plants, Genetically Modified - metabolism; Plants, Genetically Modified - physiology; Synechocystis; Synechocystis - enzymology; Synechocystis - genetics; Synechocystis - physiology; tocochromanol; tocopherol cyclase; vitamin E; Vitamin E - biosynthesis; Arabidopsis thaliana; Gene; Cruciferae; Dicotyledones; Angiospermae; Spermatophyta; Biosynthesis; Mutation; Antioxidant; Photosynthesis; Tocopherol
• ISSN: 1360-1385; 1878-4372
• DOI: 10.1016/j.tplants.2005.10.007

Tocochromanols are a group of four tocopherols and four tocotrienols that collectively constitute vitamin E, an essential nutrient in the human diet. Tocochromanols are only synthesized in oxygenic photosynthetic organisms. Although they have similar antioxidant activities in vitro, the individual tocochromanols vary widely in their in vivo vitamin E activities. During the past several years, mutant and transgenic approaches in model organisms, particularly in Arabidopsis thaliana and Synechocystis sp. PCC6803, have allowed the full complement of core pathway genes to be isolated and studied. Pathway engineering with these genes has provided significant insights into the molecular genetic and biochemical control of tocochromanol biosynthesis in plants. The resulting knowledge base is driving efforts to manipulate the levels of this essential nutrient in staple crops for populations in the developed and developing world.