title: Molecular basis for the behavioral effects of the odorant degrading enzyme Esterase 6 in Drosophila.
abstract: Previous electrophysiological and behavioural studies implicate esterase 6 in the processing of the pheromone cis-vaccenyl acetate and various food odorants that affect aggregation and reproductive behaviours. Here we show esterase 6 has relatively high activity against many of the short-mid chain food esters, but negligible activity against cis-vaccenyl acetate. The crystal structure of esterase 6 confirms its substrate-binding site can accommodate many short-mid chain food esters but not cis-vaccenyl acetate. Immunohistochemical assays show esterase 6 is expressed in non-neuronal cells in the third antennal segment that could be accessory or epidermal cells surrounding numerous olfactory sensilla, including basiconics involved in food odorant detection. Esterase 6 is also produced in trichoid sensilla, but not in the same cell types as the cis-vaccenyl acetate binding protein LUSH. Our data support a model in which esterase 6 acts as a direct odorant degrading enzyme for many bioactive food esters, but not cis-vaccenyl acetate.
authors.affiliation: CSIRO Land and Water, Black Mountain, Canberra, ACT, 2601, Australia.|Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia.
authors.forename: Faisal
authors.initials: F
authors.lastname: Younus
authors.affiliation: Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Fraser
authors.affiliation: CSIRO Land and Water, Black Mountain, Canberra, ACT, 2601, Australia.
authors.forename: Chris W
authors.initials: CW
authors.lastname: Coppin
authors.affiliation: CSIRO Land and Water, Black Mountain, Canberra, ACT, 2601, Australia.
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Liu
authors.affiliation: Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia.
authors.forename: Galen J
authors.initials: GJ
authors.lastname: Correy
authors.affiliation: Université Pierre et Marie Curie, Institut d'Ecologie et des Sciences de l'Environnement de Paris, 75252, Paris, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Chertemps
authors.affiliation: CSIRO Land and Water, Black Mountain, Canberra, ACT, 2601, Australia.
authors.forename: Gunjan
authors.initials: G
authors.lastname: Pandey
authors.affiliation: Université Pierre et Marie Curie, Institut d'Ecologie et des Sciences de l'Environnement de Paris, 75252, Paris, France.
authors.forename: Martine
authors.initials: M
authors.lastname: Maïbèche
authors.affiliation: Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia.
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Jackson
authors.affiliation: CSIRO Land and Water, Black Mountain, Canberra, ACT, 2601, Australia.
authors.forename: John G
authors.initials: JG
authors.lastname: Oakeshott
mesh_terms: D000818:Animals; D057506:Arthropod Antennae / Q000201:enzymology; D001522:Behavior, Animal / Q000502:physiology*; D043182:Carboxylesterase / Q000737:chemistry / Q000378:metabolism*; D020134:Catalytic Domain; D029721:Drosophila Proteins / Q000737:chemistry / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000201:enzymology* / Q000502:physiology*; D007700:Kinetics; D008958:Models, Molecular; D009812:Odorants; D018035:Receptors, Odorant / Q000378:metabolism; D040681:Structural Homology, Protein; D013379:Substrate Specificity
chemical_list: D029721:Drosophila Proteins; C492465:Orco protein, Drosophila; D018035:Receptors, Odorant; D043182:Carboxylesterase; C468266:Est-6 protein, Drosophila