Vitamin E is a group of compounds that includes metabolites known as tocopherols, which have high antioxidant activities. Tocopherols are synthesized in plants, and their beneficial effects on human health have been reported for diseases such as coronary heart disease and cancer. | Turkish Journal of Botany Turk J Bot (2017) 41: 559-568 © TÜBİTAK doi: Research Article Molecular characterization of tocopherol biosynthesis genes from Olea europaea (L.) cv. Ayvalık 1, 2 Fatih SEZER *, Kemal Melik TAŞKIN Department of Biology, Graduate School of Natural and Applied Sciences, Çanakkale Onsekiz Mart University, Çanakkale, Turkey 2 Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Çanakkale Onsekiz Mart University, Çanakkale, Turkey 1 Received: Accepted/Published Online: Final Version: Abstract: Vitamin E is a group of compounds that includes metabolites known as tocopherols, which have high antioxidant activities. Tocopherols are synthesized in plants, and their beneficial effects on human health have been reported for diseases such as coronary heart disease and cancer. Here we report the full-length transcripts encoding vitamin E biosynthetic enzymes from fruit mesocarp tissues using the rapid amplification of cDNA ends (RACE) method for the first time in olives. We characterized the structure of the genes 4-hydroxyphenylpyruvate dioxygenase (PDS1), homogentisate phytyltransferase 1 (HPT1), vitamin E defective 3 (VTE3), tocopherol cyclase (VTE1), and gamma tocopherol methyltransferase (GTMT), which are responsible for tocopherol biosynthesis in the olive cultivar Ayvalık. Although PDS1 is widespread in all organisms, HPT1, VTE3, VTE1, and GTMT are only present in photosynthetic organisms. We isolated total RNA from the dissected mesocarp tissues of fruit collected at 15-day intervals between October and December 2014. We compared the expression levels of genes using quantitative RT-PCR and determined the tocopherol content using the high-performance liquid chromatography–fluorescence detection (HPLC-FLD) technique during fruit maturation in the Ayvalık cultivar. High OeHPT1, OeVTE3, OeVTE1, and OeGTMT expression was noted
