Search results for "Olfactory receptor"

Characterization of rat glutathione transferases in olfactory epithelium and mucus

2019

International audience; The olfactory epithelium is continuously exposed to exogenous chemicals, including odorants. During the past decade, the enzymes surrounding the olfactory receptors have been shown to make an important contribution to the process of olfaction. Mammalian xenobiotic metabolizing enzymes, such as cytochrome P450, esterases and glutathione transferases (GSTs), have been shown to participate in odorant clearance from the olfactory receptor environment, consequently contributing to the maintenance of sensitivity toward odorants. GSTs have previously been shown to be involved in numerous physiological processes, including detoxification, steroid hormone biosynthesis, and am…

3D-QSAR study of ligands for a human olfactory receptor

2005

Abstract Only about 350 olfactory receptors (OR) provide a basis for the remarkable ability of humans to recognise and discriminate a large number of odorants. A recent study reports the odorant repertoire of a human class II OR called OR1G1, including both agonists and antagonists. We used these affinity data to perform a 3D molecular modelling study of these ligands using Catalyst/HypoGen software (Catalyst v4.9.1, Accelrys Inc., San Diego, 2004) to propose alignment models for OR1G1 ligands. We obtained a triple-alignment model, which satisfactorily explained the experimental activities and was able both to predict the antagonist effects of some compounds and to identify new potent agoni…

2019

The olfactory epithelium is continuously exposed to exogenous chemicals, including odorants. During the past decade, the enzymes surrounding the olfactory receptors have been shown to make an important contribution to the process of olfaction. Mammalian xenobiotic metabolizing enzymes, such as cytochrome P450, esterases and glutathione transferases (GSTs), have been shown to participate in odorant clearance from the olfactory receptor environment, consequently contributing to the maintenance of sensitivity toward odorants. GSTs have previously been shown to be involved in numerous physiological processes, including detoxification, steroid hormone biosynthesis, and amino acid catabolism. The…

Glutathione conjugation of the rabbit mammary pheromone 2-methylbut-2-enal

2008

International audience; In the process of smell, the olfactory signal is initiated by the binding of odorous molecules to olfactory receptors. In the receptor environment,associated events are supposed to modulate this signal.Thus, the xenobiotic metabolizing enzymes, potentially involved in the clearance of the odorous molecules, could modulate the availability of these molecules for the olfactory receptors, and consequently could participate indirectly in the olfactory signal termination. A mammary pheromone, which is an odorous aldehyde (2-methylbut-2-enal or 2MB2) has been recently characterized in the rabbit by our group. The aim of this work was to elucidate the metabolism of 2MB2 in …

Attracted or repelled?--a matter of two neurons, one pheromone binding protein, and a chiral center.

1998

Abstract Two species of scarab beetles, the Osaka beetle (Anomala osakana) and the Japanese beetle (Popillia japonica), utilize the opposite enantiomers of japonilure, (Z)-5-(1-decenyl)oxacyclopentan-2-one, as their sex pheromones. Each species produces only one of the enantiomers that functions as its own sex pheromone and as a very strong behavioral antagonist for the other species. Using an integrated approach we tested whether the discrimination of these two opposite signals is due to selective filtering by pheromone binding proteins or whether it originates in the specificity of ligand–receptor interactions. We found that the antennae of each of these two scarab species contain only a …

G-protein-coupled odorant receptors underlie mechanosensitivity in olfactory sensory neurons

2012

G-protein-coupled odorant receptors underlie mechanosensitivity in olfactory sensory neurons. 34. annual meeting - Association for chemoreception sciences (AChemS)

Modeling the insect mushroom bodies: application to a delayed match-to-sample task.

2013

Despite their small brains, insects show advanced capabilities in learning and task solving. Flies, honeybees and ants are becoming a reference point in neuroscience and a main source of inspiration for autonomous robot design issues and control algorithms. In particular, honeybees demonstrate to be able to autonomously abstract complex associations and apply them in tasks involving different sensory modalities within the insect brain. Mushroom Bodies (MBs) are worthy of primary attention for understanding memory and learning functions in insects. In fact, even if their main role regards olfactory conditioning, they are involved in many behavioral achievements and learning capabilities, as …

G protein-coupled odorant receptors underlie mechanosensitivity in mammalian olfactory sensory neurons

2014

Mechanosensitive cells are essential for organisms to sense the external and internal environments, and a variety of molecules have been implicated as mechanical sensors. Here we report that odorant receptors (ORs), a large family of G protein-coupled receptors, underlie the responses to both chemical and mechanical stimuli in mouse olfactory sensory neurons (OSNs). Genetic ablation of key signaling proteins in odor transduction or disruption of OR–G protein coupling eliminates mechanical responses. Curiously, OSNs expressing different OR types display significantly different responses to mechanical stimuli. Genetic swap of putatively mechanosensitive ORs abolishes or reduces mechanical res…

Extracellular loop 2 of G protein-coupled olfactory receptors is critical for odorant recognition

2021

International audience; G protein-coupled olfactory receptors (ORs) enable us to detect innumerous odorants. They are also ectopically expressed in non-olfactory tissues and emerging as attractive drug targets. ORs can be promiscuous or highly specific, which is part of a larger mechanism for odor discrimination. Here, we demonstrate that the OR extracellular loop 2 (ECL2) plays critical roles in OR promiscuity and specificity. Using site-directed mutagenesis and molecular modeling, we constructed 3D OR models in which ECL2 forms a lid over the orthosteric pocket. We demonstrate using molecular dynamics simulations that ECL2 controls the shape and the volume of the odorant-binding pocket, m…

3D-QSAR study of ligands for two human olfactory receptors

2007

National audience