title: An histidine covalent receptor and butenolide complex mediates strigolactone perception.
abstract: Strigolactone plant hormones control plant architecture and are key players in both symbiotic and parasitic interactions. They contain an ABC tricyclic lactone connected to a butenolide group, the D ring. The DWARF14 (D14) strigolactone receptor belongs to the superfamily of α/β-hydrolases, and is known to hydrolyze the bond between the ABC lactone and the D ring. Here we characterized the binding and catalytic functions of RAMOSUS3 (RMS3), the pea (Pisum sativum) ortholog of rice (Oryza sativa) D14 strigolactone receptor. Using new profluorescent probes with strigolactone-like bioactivity, we found that RMS3 acts as a single-turnover enzyme that explains its apparent low enzymatic rate. We demonstrated the formation of a covalent RMS3-D-ring complex, essential for bioactivity, in which the D ring was attached to histidine 247 of the catalytic triad. These results reveal an undescribed mechanism of plant hormone reception in which the receptor performs an irreversible enzymatic reaction to generate its own ligand.
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.|Howard Hughes Medical Institute.|Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
authors.forename: Alexandre
authors.initials: A
authors.lastname: de Saint Germain
authors.affiliation: Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Clavé
authors.affiliation: Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette, France.
authors.forename: Marie-Ange
authors.initials: MA
authors.lastname: Badet-Denisot
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Pillot
authors.affiliation: Institut de Biologie Intégrative de la Cellule, CNRS, CEA, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91190 Gif-sur-Yvette, France.
authors.forename: David
authors.initials: D
authors.lastname: Cornu
authors.affiliation: Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Le Caer
authors.affiliation: Howard Hughes Medical Institute.|Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
authors.forename: Marco
authors.initials: M
authors.lastname: Burger
authors.affiliation: Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette, France.
authors.forename: Frank
authors.initials: F
authors.lastname: Pelissier
authors.affiliation: Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Retailleau
authors.affiliation: Division of Cell and Molecular Biology, Imperial College London, London SW7 2AZ, United Kingdom.
authors.forename: Colin
authors.initials: C
authors.lastname: Turnbull
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Bonhomme
authors.affiliation: Howard Hughes Medical Institute.|Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
authors.forename: Joanne
authors.initials: J
authors.lastname: Chory
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Rameau
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.|Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette, France.
authors.forename: François-Didier
authors.initials: FD
authors.lastname: Boyer
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D006575:Heterocyclic Compounds, 3-Ring / Q000378:metabolism*; D006639:Histidine / Q000737:chemistry / Q000378:metabolism*; D007783:Lactones / Q000378:metabolism*; D008024:Ligands; D015394:Molecular Structure; D018532:Pisum sativum / Q000201:enzymology / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000737:chemistry / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: C000591191:GR24 strigolactone; D006575:Heterocyclic Compounds, 3-Ring; D007783:Lactones; D008024:Ligands; D010937:Plant Growth Regulators; D010940:Plant Proteins; D006639:Histidine; C004511:butenolide; D015107:4-Butyrolactone