Olfactory receptor accessory proteins play crucial roles in receptor function and gene choice
- Duke University Medical Center, United States
- Tokyo University of Agriculture and Technology, Japan
Abstract
Each of the olfactory sensory neurons (OSNs) chooses to express a single G protein-coupled olfactory receptor (OR) from a pool of hundreds. Here, we show the receptor transporting protein (RTP) family members play a dual role in both normal OR trafficking and determining OR gene choice probabilities. Rtp1 and Rtp2 double knockout mice (RTP1,2DKO) show OR trafficking defects and decreased OSN activation. Surprisingly, we discovered a small subset of the ORs are expressed in larger numbers of OSNs despite the presence of fewer total OSNs in RTP1,2DKO. Unlike typical ORs, some overrepresented ORs show robust cell surface expression in heterologous cells without the co-expression of RTPs. We present a model in which developing OSNs exhibit unstable OR expression until they choose to express an OR that exits the ER or undergo cell death. Our study sheds light on the new link between OR protein trafficking and OR transcriptional regulation.
Data availability
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Olfactory receptor accessory proteins play crucial roles in receptor gene choicePublicly available at the NCBI Gene Expression Omnibus (accession no: GSE87694).
Article and author information
Author details
Funding
National Institutes of Health (R01 DC014423)
- Hiroaki Matsunami
National Institutes of Health (R01 DC012095)
- Hiroaki Matsunami
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (A161-16-07) of the Duke Animal Care and Use program.
Copyright
© 2017, Sharma et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Olfactory receptor accessory proteins play crucial roles in receptor function and gene choice
eLife 6:e21895.
https://doi.org/10.7554/eLife.21895
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