Molecules and Cells

Korean Society for Molecular and Cellular Biology (한국분자세포생물학회)
권호 표지

Overexpression of Arabidopsis Homogentisate Phytyltransferase or Tocopherol Cyclase Elevates Vitamin E Content by Increasing γ-tocopherol Level in Lettuce (Lactuca sativa L.)

  • Lee, Koeun (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University) ;
  • Lee, Sa Mi (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University) ;
  • Park, Sang-Ryoung (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University) ;
  • Jung, Jinwook (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University) ;
  • Moon, Joon-Kwan (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University) ;
  • Cheong, Jong-Joo (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University) ;
  • Kim, Minkyun (School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University)
  • Received : 2007.04.05
  • Accepted : 2007.06.11
  • Published : 2007.10.31
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Abstract

Tocopherols, essential components of the human diet, are synthesized exclusively by photosynthetic organisms. To increase tocopherol content by increasing total flux to the tocopherol biosynthetic pathway, genes encoding Arabidopsis homogentisate phytyltransferase (HPT/V-TE2) and tocopherol cyclase (TC/VTE1) were constitutively overexpressed in lettuce (Lactuca sativa L.). Total tocopherol content of the transgenic plants overexpressing either of the genes was increased by more than 2-fold mainly due to an increase in ${\gamma}$-tocopherol. However, chlorophyll content in the HPT/VTE2 and TC/VTE1 transgenic lines decreased by up to 20% and increased by up to 35%, respectively (P < 0.01). These results demonstrate that manipulation of the tocopherol biosynthetic pathway can increase or decrease chlorophyll content depending on the gene introduced.

Keywords

Acknowledgement

Supported by : Korean Ministry of Science and Technology

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