Sélection de la langue

Gouvernement du Canada / Government of Canada

Recherche

Arabidopsis thaliana CYP98A3 mediating aromatic 3-hydroxylation. Developmental regulation of the gene, and expression in yeast

Par Conseil national de recherches du Canada

DOITrouver le DOI : https://doi.org/10.1104/pp.008649
AuteurRechercher : 1; Rechercher : 1; Rechercher : 1; Rechercher : 1; Rechercher : 1; Rechercher : 1; Rechercher : 1
Affiliation
  1. Conseil national de recherches du Canada. Institut de biotechnologie des plantes du CNRC
FormatArticle
Résumé
The general phenylpropanoid pathways generate a wide array of aromatic secondary metabolites that range from monolignols, which are ubiquitous in all plants, to sinapine, which is confined to crucifer seeds. The biosynthesis of these compounds involves hydroxylated and methoxylated cinnamyl acid, aldehyde, or alcohol intermediates. Of the three enzymes originally proposed to hydroxylate the 4-, 3-, and 5-positions of the aromatic ring, cinnamate 4-hydroxylase (C4H), which converts trans-cinnamic acid top-coumaric acid, is the best characterized and is also the archetypal plant P450 monooxygenase. Ferulic acid 5-hydroxylase (F5H), a P450 that catalyzes 5-hydroxylation, has also been studied, but the presumptive 3-hydroxylase converting p-coumarate to caffeate has been elusive. We have found that Arabidopsis CYP98A3, also a P450, could hydroxylate p-coumaric acid to caffeic acid in vivo when expressed in yeast (Saccharomyces cerevisiae) cells, albeit very slowly.CYP98A3 transcript was found in Arabidopsis stem and silique, resembling both C4H and F5Hin this respect. CYP98A3 showed further resemblance toC4H in being highly active in root, but differed fromF5H in this regard. In transgenic Arabidopsis, the promoters of CYP98A3 and C4H showed wound inducibility and a comparable developmental regulation throughout the life cycle, except in seeds, where the CYP98A3 promoter construct was inactive while remaining active in silique walls. Within stem and root tissue, the gene product and the promoter activity ofCYP98A3 were most abundant in lignifying cells. Collectively, these studies show involvement of CYP98A3 in the general phenylpropanoid metabolism, and suggest a downstream function for CYP98A3 relative to the broader and upstream role of C4H.
Date de publication
Maison d’éditionOxford Academic
American Society of Plant Biologists
Dans
  • Plant Physiology 130, nº 1 (septembre 2002) : 210–220.
Langueanglais
Publications évaluées par des pairsOui
Numéro NPARC13053413
Exporter la noticeExporter en format RIS
Signaler une correctionSignaler une correction (s'ouvre dans un nouvel onglet)
Identificateur de l’enregistrementaa8a6f42-70f4-40f3-a023-d0439837dde5
Enregistrement créé2009-11-25
Enregistrement modifié2023-04-11
Date de modification :