title: Odorant-binding proteins and xenobiotic metabolizing enzymes: implications in olfactory perireceptor events.
abstract: At the periphery of the olfactory system, the binding of odorants on olfactory receptors (ORs) is usually thought to be the first level of the perception of smell. However, at this stage, there is evidence that other molecular mechanisms also interfere with this chemoreception by ORs. These perireceptor events are mainly supported by two groups of proteins present in the olfactory nasal mucus or in the nasal epithelium. Odorant-binding proteins (OBPs), the first group of proteins have been investigated for many years. OBPs are small carrier proteins capable of binding odorants with affinities in the micromolar range. Although there is no absolute evidence to support their functional roles in vertebrates, OBPs are good candidates for the transport of inhaled odorants towards the ORs via the nasal mucus. The second group of proteins involves xenobiotic metabolizing enzymes, which are strongly expressed in the olfactory epithelium and supposed to be involved in odorant transformation, degradation, and/or olfactory signal termination. Following an overview of these proteins, this review explores their roles, which are still a matter of debate.
authors.affiliation: INRA UMR1324, CNRS UMR6265, Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation, F-21000, Dijon, France.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Heydel
authors.forename: Alexandra
authors.initials: A
authors.lastname: Coelho
authors.forename: Nicolas
authors.initials: N
authors.lastname: Thiebaud
authors.forename: Arièle
authors.initials: A
authors.lastname: Legendre
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Le Bon
authors.forename: Philippe
authors.initials: P
authors.lastname: Faure
authors.forename: Fabrice
authors.initials: F
authors.lastname: Neiers
authors.forename: Yves
authors.initials: Y
authors.lastname: Artur
authors.forename: Jérôme
authors.initials: J
authors.lastname: Golebiowski
authors.forename: Loïc
authors.initials: L
authors.lastname: Briand
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004798:Enzymes / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008658:Inactivation, Metabolic; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009812:Odorants; D009833:Olfactory Pathways / Q000378:metabolism; D055696:Olfactory Perception; D018034:Olfactory Receptor Neurons / Q000201:enzymology*; D011487:Protein Conformation; D018035:Receptors, Odorant / Q000737:chemistry / Q000378:metabolism*; D015398:Signal Transduction; D012903:Smell
chemical_list: D004798:Enzymes; D008024:Ligands; D018035:Receptors, Odorant
keywords: chemoreception; odorant-binding protein; olfaction; xenobiotic metabolizing enzyme