A Conserved Cytochrome P450 Evolved in Seed Plants Regulates Flower Maturation.
Fiche publication
Date publication
décembre 2015
Journal
Molecular plant
Auteurs
Membres identifiés du Cancéropôle Est :
Mme DEMAIS Valérie, Dr MUTTERER Jérôme, Dr ERHARDT Mathieu
Tous les auteurs :
Liu Z, Boachon B, Lugan R, Tavares R, Erhardt M, Mutterer J, Demais V, Pateyron S, Brunaud V, Ohnishi T, Pencik A, Achard P, Gong F, Hedden P, Werck-Reichhart D, Renault H
Lien Pubmed
Résumé
Global inspection of plant genomes identifies genes maintained in low copies across taxa and under strong purifying selection, which are likely to have essential functions. Based on this rationale, we investigated the function of the low-duplicated CYP715 cytochrome P450 gene family that appeared early in seed plants and evolved under strong negative selection. Arabidopsis CYP715A1 showed a restricted tissue-specific expression in the tapetum of flower buds and in the anther filaments upon anthesis. cyp715a1 insertion lines showed a strong defect in petal development, and transient alteration of pollen intine deposition. Comparative expression analysis revealed the downregulated expression of genes involved in pollen development, cell wall biogenesis, hormone homeostasis, and floral sesquiterpene biosynthesis, especially TPS21 and several key genes regulating floral development such as MYB21, MYB24, and MYC2. Accordingly, floral sesquiterpene emission was suppressed in the cyp715a1 mutants. Flower hormone profiling, in addition, indicated a modification of gibberellin homeostasis and a strong disturbance of the turnover of jasmonic acid derivatives. Petal growth was partially restored by the active gibberellin GA3 or the functional analog of jasmonoyl-isoleucine, coronatine. CYP715 appears to function as a key regulator of flower maturation, synchronizing petal expansion and volatile emission. It is thus expected to be an important determinant of flower-insect interaction.
Mots clés
Arabidopsis, classification, Arabidopsis Proteins, chemistry, Conserved Sequence, Cytochrome P-450 Enzyme System, chemistry, Flowers, classification, Gene Expression Regulation, Developmental, Gene Expression Regulation, Plant, Phylogeny, Plants, classification, Seeds, classification
Référence
Mol Plant. 2015 Dec;8(12):1751-65