title: Gene coexpression analysis reveals complex metabolism of the monoterpene alcohol linalool in Arabidopsis flowers.
abstract: The cytochrome P450 family encompasses the largest family of enzymes in plant metabolism, and the functions of many of its members in Arabidopsis thaliana are still unknown. Gene coexpression analysis pointed to two P450s that were coexpressed with two monoterpene synthases in flowers and were thus predicted to be involved in monoterpenoid metabolism. We show that all four selected genes, the two terpene synthases (TPS10 and TPS14) and the two cytochrome P450s (CYP71B31 and CYP76C3), are simultaneously expressed at anthesis, mainly in upper anther filaments and in petals. Upon transient expression in Nicotiana benthamiana, the TPS enzymes colocalize in vesicular structures associated with the plastid surface, whereas the P450 proteins were detected in the endoplasmic reticulum. Whether they were expressed in Saccharomyces cerevisiae or in N. benthamiana, the TPS enzymes formed two different enantiomers of linalool: (-)-(R)-linalool for TPS10 and (+)-(S)-linalool for TPS14. Both P450 enzymes metabolize the two linalool enantiomers to form different but overlapping sets of hydroxylated or epoxidized products. These oxygenated products are not emitted into the floral headspace, but accumulate in floral tissues as further converted or conjugated metabolites. This work reveals complex linalool metabolism in Arabidopsis flowers, the ecological role of which remains to be determined.
authors.affiliation: Institute of Plant Molecular Biology, Centre National de la Recherche Scientifique Unité Propre de Recherche 2357, University of Strasbourg, F-67000 Strasbourg, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Ginglinger
authors.forename: Benoit
authors.initials: B
authors.lastname: Boachon
authors.forename: René
authors.initials: R
authors.lastname: Höfer
authors.forename: Christian
authors.initials: C
authors.lastname: Paetz
authors.forename: Tobias G
authors.initials: TG
authors.lastname: Köllner
authors.forename: Laurence
authors.initials: L
authors.lastname: Miesch
authors.forename: Raphael
authors.initials: R
authors.lastname: Lugan
authors.forename: Raymonde
authors.initials: R
authors.lastname: Baltenweck
authors.forename: Jérôme
authors.initials: J
authors.lastname: Mutterer
authors.forename: Pascaline
authors.initials: P
authors.lastname: Ullmann
authors.forename: Franziska
authors.initials: F
authors.lastname: Beran
authors.forename: Patricia
authors.initials: P
authors.lastname: Claudel
authors.forename: Francel
authors.initials: F
authors.lastname: Verstappen
authors.forename: Marc J C
authors.initials: MJ
authors.lastname: Fischer
authors.forename: Francis
authors.initials: F
authors.lastname: Karst
authors.forename: Harro
authors.initials: H
authors.lastname: Bouwmeester
authors.forename: Michel
authors.initials: M
authors.lastname: Miesch
authors.forename: Bernd
authors.initials: B
authors.lastname: Schneider
authors.forename: Jonathan
authors.initials: J
authors.lastname: Gershenzon
authors.forename: Jürgen
authors.initials: J
authors.lastname: Ehlting
authors.forename: Danièle
authors.initials: D
authors.lastname: Werck-Reichhart
mesh_terms: D000080462:Acyclic Monoterpenes; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D019753:Intramolecular Lyases / Q000235:genetics / Q000378:metabolism; D039821:Monoterpenes / Q000378:metabolism*; D009154:Mutation; D030821:Plants, Genetically Modified; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014026:Nicotiana / Q000235:genetics
chemical_list: D000080462:Acyclic Monoterpenes; D029681:Arabidopsis Proteins; D039821:Monoterpenes; D003577:Cytochrome P-450 Enzyme System; C018584:linalool; D019753:Intramolecular Lyases; C108134:TPS10 protein, Arabidopsis