Transgenic Research

, Volume 21, Issue 5, pp 1093–1097

Transgenic rice grains expressing a heterologous ρ-hydroxyphenylpyruvate dioxygenase shift tocopherol synthesis from the γ to the α isoform without increasing absolute tocopherol levels

  • Gemma Farré
  • Duraialagaraja Sudhakar
  • Shaista Naqvi
  • Gerhard Sandmann
  • Paul Christou
  • Teresa Capell
  • Changfu Zhu
Brief Communication

DOI: 10.1007/s11248-012-9601-7

Cite this article as:
Farré, G., Sudhakar, D., Naqvi, S. et al. Transgenic Res (2012) 21: 1093. doi:10.1007/s11248-012-9601-7

Abstract

We generated transgenic rice plants overexpressing Arabidopsis thaliana ρ-hydroxyphenylpyruvate dioxygenase (HPPD), which catalyzes the first committed step in vitamin E biosynthesis. Transgenic grains accumulated marginally higher levels of total tocochromanols than controls, reflecting a small increase in absolute tocotrienol synthesis (but no change in the relative abundance of the α and γ isoforms). In contrast, there was no change in the absolute tocopherol level, but a significant shift from the γ to the α isoform. These data confirm HPPD is not rate limiting, and that increasing flux through the early pathway reveals downstream bottlenecks that act as metabolic tipping points.

Keywords

Vitamin E Tocochromanols Metabolic engineering Transgenic rice 

Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Gemma Farré
    • 1
  • Duraialagaraja Sudhakar
    • 2
  • Shaista Naqvi
    • 1
  • Gerhard Sandmann
    • 3
  • Paul Christou
    • 1
    • 4
  • Teresa Capell
    • 1
  • Changfu Zhu
    • 1
  1. 1.Departament de Producció Vegetal i Ciència ForestalUniversitat de Lleida-CRALleidaSpain
  2. 2.Department of Plant Molecular Biology and Biotechnology, Centre for Plant Molecular BiologyTamil Nadu Agricultural UniversityCoimbatoreIndia
  3. 3.Biosynthesis Group, Molecular BiosciencesJohann Wolfgang Goethe UniversitätFrankfurtGermany
  4. 4.Institució Catalana de Recerca I Estudis AvançatsBarcelonaSpain