Elucidation of the beta-carotene hydroxylation pathway in Arabidopsis thaliana

FEBS Lett. 2006 Aug 21;580(19):4718-22. doi: 10.1016/j.febslet.2006.07.055. Epub 2006 Jul 26.


The first dedicated step in plant xanthophyll biosynthesis is carotenoid hydroxylation. In Arabidopsis thaliana, this reaction is performed by both heme (LUT1 and LUT5) and non-heme (CHY1 and CHY2) hydroxylases. No mutant completely abolishing alpha- or beta-carotene hydroxylation has been described to date. We constructed double and triple mutant combinations in CHY1, CHY2, LUT1, LUT5 and LUT2 (lycopene epsilon-cyclase). In chy1chy2lut2, 80% of leaf carotenoids is represented by beta-carotene. In chy1chy2lut5, beta-carotene hydroxylation is completely abolished, while hydroxylation of the beta-ring of alpha-carotene is still observed. The data are consistent with a role of LUT5 in beta-ring hydroxylation, and with the existence of an additional hydroxylase, acting on the beta-ring of alpha-, but not beta-carotene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Base Sequence
  • DNA Primers
  • Genes, Plant
  • Hydroxylation
  • Reverse Transcriptase Polymerase Chain Reaction
  • beta Carotene / metabolism*


  • DNA Primers
  • beta Carotene