title: The path from β-carotene to carlactone, a strigolactone-like plant hormone.
abstract: Strigolactones, phytohormones with diverse signaling activities, have a common structure consisting of two lactones connected by an enol-ether bridge. Strigolactones derive from carotenoids via a pathway involving the carotenoid cleavage dioxygenases 7 and 8 (CCD7 and CCD8) and the iron-binding protein D27. We show that D27 is a β-carotene isomerase that converts all-trans-β-carotene into 9-cis-β-carotene, which is cleaved by CCD7 into a 9-cis-configured aldehyde. CCD8 incorporates three oxygens into 9-cis-β-apo-10'-carotenal and performs molecular rearrangement, linking carotenoids with strigolactones and producing carlactone, a compound with strigolactone-like biological activities. Knowledge of the structure of carlactone will be crucial for understanding the biology of strigolactones and may have applications in combating parasitic weeds.
authors.affiliation: Faculty of Biology, University of Freiburg, Freiburg, Germany.
authors.forename: Adrian
authors.initials: A
authors.lastname: Alder
authors.forename: Muhammad
authors.initials: M
authors.lastname: Jamil
authors.forename: Mattia
authors.initials: M
authors.lastname: Marzorati
authors.forename: Mark
authors.initials: M
authors.lastname: Bruno
authors.forename: Martina
authors.initials: M
authors.lastname: Vermathen
authors.forename: Peter
authors.initials: P
authors.lastname: Bigler
authors.forename: Sandro
authors.initials: S
authors.lastname: Ghisla
authors.forename: Harro
authors.initials: H
authors.lastname: Bouwmeester
authors.forename: Peter
authors.initials: P
authors.lastname: Beyer
authors.forename: Salim
authors.initials: S
authors.lastname: Al-Babili
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D053898:Biosynthetic Pathways; D002338:Carotenoids / Q000737:chemistry / Q000378:metabolism; D049308:Dioxygenases / Q000235:genetics / Q000378:metabolism; D018525:Germination; D007535:Isomerases / Q000235:genetics / Q000378:metabolism; D007783:Lactones / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D015394:Molecular Structure; D009154:Mutation; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D018532:Pisum sativum / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010937:Plant Growth Regulators / Q000096:biosynthesis* / Q000737:chemistry; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D013237:Stereoisomerism; D034362:Striga / Q000254:growth & development; D019207:beta Carotene / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C507382:GR24 compound; D007783:Lactones; D010937:Plant Growth Regulators; D010940:Plant Proteins; C427759:beta-apo-10'-carotenal; C571055:carlactone; D019207:beta Carotene; D002338:Carotenoids; C494441:CCD7 protein, Arabidopsis; C494442:CCD8 protein, Arabidopsis; D049308:Dioxygenases; C571056:D27 isomerase, Oryza sativa; D007535:Isomerases