A novel cation-dependent o-methyltransferase involved in anthocyanin methylation in grapevine - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement Accéder directement au contenu
Article Dans Une Revue Plant Physiology Année : 2009

A novel cation-dependent o-methyltransferase involved in anthocyanin methylation in grapevine

Résumé

Anthocyanins are major pigments in colored grape (Vitis vinifera) berries, and most of them are monomethoxylated or dimethoxylated. We report here the functional characterization of an anthocyanin O-methyltransferase (AOMT) from grapevine. The expression pattern in two cultivars with different anthocyanin methylation profiles (Syrah and Nebbiolo) showed a peak at start ripening (ve´raison), when the concentrations of all methylated anthocyanins begin to increase. The purified recombinant AOMT protein was active on both anthocyanins and flavonols in vitro, with Km in the micromolar range, and was dependent on divalent cations for activity. AOMT showed a preference for 3#,5# methylation when a 3#,4#,5# hydroxylated anthocyanin substrate was tested. In order to assess its in planta activity, we performed transient expression of AOMT in tobacco (Nicotiana benthamiana) leaves expressing the Production of Anthocyanin Pigment1 (PAP1) transcription factor from Arabidopsis (Arabidopsis thaliana). PAP1 expression in leaves induced the accumulation of the nonmethylated anthocyanin delphinidin 3-rutinoside. The coexpression of PAP1 and AOMT resulted in an accumulation of malvidin 3-rutinoside.We also showed that AOMT localized exclusively in the cytoplasm of tobacco leaf cells. These results demonstrate the ability of this enzyme to methylate anthocyanins both in vitro and in vivo, indicating that AOMT plays a major role in anthocyanin biosynthesis in grape berries.

Dates et versions

hal-02659192 , version 1 (30-05-2020)

Identifiants

Citer

Philippe Hugueney, Sofia Provenzano, Clotilde Verries, Alessandra Ferrandino, Emmanuelle Meudec, et al.. A novel cation-dependent o-methyltransferase involved in anthocyanin methylation in grapevine. Plant Physiology, 2009, 150, pp.2057-2070. ⟨10.1104/pp.109.140376⟩. ⟨hal-02659192⟩
21 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More