Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing

Dogs have an exquisite sense of olfaction. In many instances this ability has been utilized by humans for a wide range of important situations including detecting explosives and illegal drugs. It is accepted that some breeds have better senses of smell than others. Dogs can detect many volatile comp...

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Autores principales: Azzouzi, Naoual, Guillory, Anne-Sophie, Chaudieu, Gilles, Galibert, Francis
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9121576/
https://www.ncbi.nlm.nih.gov/pubmed/35596227
http://dx.doi.org/10.1186/s40575-022-00116-7
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author Azzouzi, Naoual
Guillory, Anne-Sophie
Chaudieu, Gilles
Galibert, Francis
author_facet Azzouzi, Naoual
Guillory, Anne-Sophie
Chaudieu, Gilles
Galibert, Francis
author_sort Azzouzi, Naoual
collection PubMed
description Dogs have an exquisite sense of olfaction. In many instances this ability has been utilized by humans for a wide range of important situations including detecting explosives and illegal drugs. It is accepted that some breeds have better senses of smell than others. Dogs can detect many volatile compounds at extremely low concentrations in air. To achieve such high levels of detection, the canine olfactory system is both complex and highly developed requiring a high density of olfactory receptors capable of detecting volatiles. Consequently the dog genome encodes a large number of olfactory receptor (OR) genes. However, it remains unclear as to what extent are all of these OR genes expressed on the cell surface.  To facilitate such studies, a nasal brushing method was developed to recover dog nasal epithelial cell samples from which total RNA could be extracted and used to prepare high quality cDNA libraries. After capture by hybridization with an extensive set of oligonucleotides, the level of expression of each transcript was measured following next generation sequencing (NGS). The reproducibility of this sampling approach was checked by analyzing replicate samples from the same animal (up to 6 per each naris). The quality of the hybridization capture was also checked by analyzing two DNA libraries; this offered an advantage over RNA libraries by having an equal presence for each gene. Finally, we compared this brushing method performed on living dogs to a nasal epithelium biopsy approach applied to two euthanized terminally ill dogs, following consent from their owners. Comparison the expression levels of each transcript indicate that the ratios of expression between the highest and the least expressed OR in each sample are greater than 10,000 (paralog variation). Furthermore, it was clear that a number of OR genes are not expressed. The method developed and described here will allow researchers to further address whether variations observed in the OR transcriptome relate to dog ‘life experiences’ and whether any differences observed between samples are dog-specific or breed-specific. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40575-022-00116-7.
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spelling pubmed-91215762022-05-21 Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing Azzouzi, Naoual Guillory, Anne-Sophie Chaudieu, Gilles Galibert, Francis Canine Med Genet Research Dogs have an exquisite sense of olfaction. In many instances this ability has been utilized by humans for a wide range of important situations including detecting explosives and illegal drugs. It is accepted that some breeds have better senses of smell than others. Dogs can detect many volatile compounds at extremely low concentrations in air. To achieve such high levels of detection, the canine olfactory system is both complex and highly developed requiring a high density of olfactory receptors capable of detecting volatiles. Consequently the dog genome encodes a large number of olfactory receptor (OR) genes. However, it remains unclear as to what extent are all of these OR genes expressed on the cell surface.  To facilitate such studies, a nasal brushing method was developed to recover dog nasal epithelial cell samples from which total RNA could be extracted and used to prepare high quality cDNA libraries. After capture by hybridization with an extensive set of oligonucleotides, the level of expression of each transcript was measured following next generation sequencing (NGS). The reproducibility of this sampling approach was checked by analyzing replicate samples from the same animal (up to 6 per each naris). The quality of the hybridization capture was also checked by analyzing two DNA libraries; this offered an advantage over RNA libraries by having an equal presence for each gene. Finally, we compared this brushing method performed on living dogs to a nasal epithelium biopsy approach applied to two euthanized terminally ill dogs, following consent from their owners. Comparison the expression levels of each transcript indicate that the ratios of expression between the highest and the least expressed OR in each sample are greater than 10,000 (paralog variation). Furthermore, it was clear that a number of OR genes are not expressed. The method developed and described here will allow researchers to further address whether variations observed in the OR transcriptome relate to dog ‘life experiences’ and whether any differences observed between samples are dog-specific or breed-specific. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40575-022-00116-7. BioMed Central 2022-05-20 /pmc/articles/PMC9121576/ /pubmed/35596227 http://dx.doi.org/10.1186/s40575-022-00116-7 Text en © The Author(s) 2022 https://creativecommons.org/licenses/by/4.0/Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/ (https://creativecommons.org/publicdomain/zero/1.0/) ) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
spellingShingle Research
Azzouzi, Naoual
Guillory, Anne-Sophie
Chaudieu, Gilles
Galibert, Francis
Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
title Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
title_full Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
title_fullStr Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
title_full_unstemmed Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
title_short Dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
title_sort dog olfactory receptor gene expression profiling using samples derived from nasal epithelium brushing
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9121576/
https://www.ncbi.nlm.nih.gov/pubmed/35596227
http://dx.doi.org/10.1186/s40575-022-00116-7
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