Project description:A fundamental challenge in studying principles of organization used by the olfactory system to encode odor concentration information has been to identify comprehensive sets of activated odorant receptors (ORs) across a broad concentration range inside freely behaving animals. In mammals, this has recently become feasible with high-throughput sequencing-based methods that identify populations of activated ORs in vivo. In this study, we characterized the mouse OR repertoires activated by the two odorants, acetophenone and 2,5-dihydro-2,4,5-trimethylthiazoline, from 0.01% to 100% (v/v) as starting concentrations using phosphorylated ribosomal protein S6 capture followed by RNA-Seq. We found Olfr923 to be one of the most sensitive ORs that is enriched by acetophenone. Using a mouse line that genetically labels Olfr923-positive axons, we provided evidence that acetophenone activates the Olfr923 glomeruli in the olfactory bulb. Through molecular dynamics stimulations, we identified amino acid residues in the Olfr923 binding cavity that facilitates acetophenone binding. This study sheds light on the active process by which unique OR repertoires may collectively facilitate the discrimination of odorant concentrations.
Project description:A fundamental challenge in studying principles of organization used by the olfactory system to encode odor concentration information has been identifying comprehensive sets of activated odorant receptors (ORs) across a broad concentration range inside freely behaving animals. In mammals, this has recently become feasible with high-throughput sequencing-based methods that identify populations of activated ORs in vivo In this study, we characterized the mouse OR repertoires activated by the two odorants, acetophenone (ACT) and 2,5-dihydro-2,4,5-trimethylthiazoline (TMT), from 0.01% to 100% (v/v) as starting concentrations using phosphorylated ribosomal protein S6 capture followed by RNA-Seq. We found Olfr923 to be one of the most sensitive ORs that is enriched by ACT. Using a mouse line that genetically labels Olfr923-positive axons, we provided evidence that ACT activates the Olfr923 glomeruli in the olfactory bulb. Through molecular dynamics stimulations, we identified amino acid residues in the Olfr923 binding cavity that facilitate ACT binding. This study sheds light on the active process by which unique OR repertoires may collectively facilitate the discrimination of odorant concentrations.
Project description:Odorants are thought to activate sets of odorant receptors in vivo, but capturing sets of responsive receptors in vivo has never been accomplished. GeneChip microarrays were used to identify the odorant receptor mRNAs enriched in samples from activated olfactory neurons
Project description:We present a high-throughput in vivo method to identify odorant receptors responding to odorants, using phosphorylated ribosome immunoprecipitation of mRNA from olfactory epithelium of odor-stimulated mice followed by RNA-Seq. pS6-IP RNA-Seq in odor stimulated vs control mice olfactory epithelium
Project description:We present a high-throughput in vivo method to identify odorant receptors responding to odorants, using phosphorylated ribosome immunoprecipitation of mRNA from olfactory epithelium of odor-stimulated mice followed by RNA-Seq.