title: Targeted metabolomics shows plasticity in the evolution of signaling lipids and uncovers old and new endocannabinoids in the plant kingdom.
abstract: The remarkable absence of arachidonic acid (AA) in seed plants prompted us to systematically study the presence of C20 polyunsaturated fatty acids, stearic acid, oleic acid, jasmonic acid (JA), N-acylethanolamines (NAEs) and endocannabinoids (ECs) in 71 plant species representative of major phylogenetic clades. Given the difficulty of extrapolating information about lipid metabolites from genetic data we employed targeted metabolomics using LC-MS/MS and GC-MS to study these signaling lipids in plant evolution. Intriguingly, the distribution of AA among the clades showed an inverse correlation with JA which was less present in algae, bryophytes and monilophytes. Conversely, ECs co-occurred with AA in algae and in the lower plants (bryophytes and monilophytes), thus prior to the evolution of cannabinoid receptors in Animalia. We identified two novel EC-like molecules derived from the eicosatetraenoic acid juniperonic acid, an omega-3 structural isomer of AA, namely juniperoyl ethanolamide and 2-juniperoyl glycerol in gymnosperms, lycophytes and few monilophytes. Principal component analysis of the targeted metabolic profiles suggested that distinct NAEs may occur in different monophyletic taxa. This is the first report on the molecular phylogenetic distribution of apparently ancient lipids in the plant kingdom, indicating biosynthetic plasticity and potential physiological roles of EC-like lipids in plants.
authors.affiliation: Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
authors.forename: María Salomé
authors.initials: MS
authors.lastname: Gachet
authors.affiliation: Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Schubert
authors.affiliation: Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
authors.forename: Serafina
authors.initials: S
authors.lastname: Calarco
authors.affiliation: School of Pharmaceutical Science, University of Geneva, University of Lausanne, 1 rue Michel Servet, 1211 Geneva 4, Switzerland.
authors.forename: Julien
authors.initials: J
authors.lastname: Boccard
authors.affiliation: Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
authors.forename: Jürg
authors.initials: J
authors.lastname: Gertsch
mesh_terms: D016718:Arachidonic Acid / Q000235:genetics / Q000378:metabolism*; D063388:Endocannabinoids / Q000235:genetics / Q000378:metabolism*; D019143:Evolution, Molecular; D050356:Lipid Metabolism; D055442:Metabolome; D010802:Phylogeny; D010944:Plants / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D063388:Endocannabinoids; D016718:Arachidonic Acid