Overexpression of homogentisate phytyltransferase (HPT) and tocopherol cyclase (TC) enhances α-tocopherol content in transgenic tobacco

oleh: M. C. Harish, P. Dachinamoorthy, S. Balamurugan, S. Bala Murugan, R. Sathishkumar

Format: Article
Diterbitkan: Institute of Experimental Botany of the Czech Academy of Sciences 2013-06-01

Deskripsi

Photosynthetic organisms synthesize the amphipathic antioxidants called tocopherols which are essential components of the human diet. To increase the α-tocopherol (vitamin E) content, Arabidopsis genes encoding homogentisate phytyltransferase (HPT) and tocopherol cyclase (TC) were constitutively expressed individually and in combination (HPT:TC) in tobacco plant by Agrobacterium mediated transformation. The transgene was confirmed by polymerase chain reaction (PCR), transgene expression was studied by reverse transcriptase (RT)-PCR, integration of the transgene in the plant genome was confirmed by Southern blot, and α-tocopherol content was quantified using high performance liquid chromatography (HPLC). The α-tocopherol content in transgenic tobacco plants expressing HPT, TC, and HPT:TC was increased by 5.4-, 4.0-, and 7.1-fold, respectively, when compared to the wild type (WT). These results indicate that, the HPT and TC activities are critical for enhancing the vitamin E content in tobacco plants.