101
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Kang W, Choi D, Park S, Park T. Carvone Decreases Melanin Content by Inhibiting Melanoma Cell Proliferation via the Cyclic Adenosine Monophosphate (cAMP) Pathway. Molecules 2020; 25:molecules25215191. [PMID: 33171851 PMCID: PMC7664693 DOI: 10.3390/molecules25215191] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/27/2022] Open
Abstract
Melanin, which determines the color of the skin and hair, is initially synthesized to protect the skin from ultraviolet light; however, excessive melanin pigmentation caused by abnormal cell proliferation can result in various melanocytic lesions. Cyclic adenosine monophosphate (cAMP) is known to regulate cell cycle progression and consequently to inhibit the division of abnormally proliferating cells. In this work, we aimed to test whether carvone, a scent compound from plants, inhibits proliferation and subsequently reduces melanin content of melanoma cells and to determine whether its beneficial effects are mediated by the cAMP pathway. We found that carvone decreases melanin content and inhibits melanoma cell proliferation in a concentration-dependent manner. Meanwhile, it inhibited the activation of cell cycle-associated proteins such as cyclin-dependent kinase 1 (CDK1). Of note, the beneficial effects of carvone were abrogated by cAMP inhibition. Our findings indicate potential benefits of carvone for the treatment of melanomas and presumably other hyperpigmentation-related dermatological disorders such as melasmas, lentigines, and excessive freckles.
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Affiliation(s)
| | | | | | - Taesun Park
- Correspondence: ; Tel.: +82-2-2123-3123; Fax: +82-2-365-3118
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102
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Baldwin MW, Ko MC. Functional evolution of vertebrate sensory receptors. Horm Behav 2020; 124:104771. [PMID: 32437717 DOI: 10.1016/j.yhbeh.2020.104771] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 04/20/2020] [Accepted: 04/28/2020] [Indexed: 12/15/2022]
Abstract
Sensory receptors enable animals to perceive their external world, and functional properties of receptors evolve to detect the specific cues relevant for an organism's survival. Changes in sensory receptor function or tuning can directly impact an organism's behavior. Functional tests of receptors from multiple species and the generation of chimeric receptors between orthologs with different properties allow for the dissection of the molecular basis of receptor function and identification of the key residues that impart functional changes in different species. Knowledge of these functionally important sites facilitates investigation into questions regarding the role of epistasis and the extent of convergence, as well as the timing of sensory shifts relative to other phenotypic changes. However, as receptors can also play roles in non-sensory tissues, and receptor responses can be modulated by numerous other factors including varying expression levels, alternative splicing, and morphological features of the sensory cell, behavioral validation can be instrumental in confirming that responses observed in heterologous systems play a sensory role. Expression profiling of sensory cells and comparative genomics approaches can shed light on cell-type specific modifications and identify other proteins that may affect receptor function and can provide insight into the correlated evolution of complex suites of traits. Here we review the evolutionary history and diversity of functional responses of the major classes of sensory receptors in vertebrates, including opsins, chemosensory receptors, and ion channels involved in temperature-sensing, mechanosensation and electroreception.
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Affiliation(s)
| | - Meng-Ching Ko
- Max Planck Institute for Ornithology, Seewiesen, Germany
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103
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Kowalewski J, Ray A. Predicting Human Olfactory Perception from Activities of Odorant Receptors. iScience 2020; 23:101361. [PMID: 32731170 PMCID: PMC7393469 DOI: 10.1016/j.isci.2020.101361] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 05/31/2020] [Accepted: 07/09/2020] [Indexed: 11/30/2022] Open
Abstract
Odor perception in humans is initiated by activation of odorant receptors (ORs) in the nose. However, the ORs linked to specific olfactory percepts are unknown, unlike in vision or taste where receptors are linked to perception of different colors and tastes. The large family of ORs (~400) and multiple receptors activated by an odorant present serious challenges. Here, we first use machine learning to screen ~0.5 million compounds for new ligands and identify enriched structural motifs for ligands of 34 human ORs. We next demonstrate that the activity of ORs successfully predicts many of the 146 different perceptual qualities of chemicals. Although chemical features have been used to model odor percepts, we show that biologically relevant OR activity is often superior. Interestingly, each odor percept could be predicted with very few ORs, implying they contribute more to each olfactory percept. A similar model is observed in Drosophila where comprehensive OR-neuron data are available. Machine learning predicted activity of 34 human ORs for ~0.5 million chemicals Activities of human ORs could predict odor character using machine learning Few OR activities were needed to optimize predictions of each odor percept Behavior predictions in Drosophila also need few olfactory receptor activities
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Affiliation(s)
- Joel Kowalewski
- Interdepartmental Neuroscience Program, University of California, Riverside, CA 92521, USA
| | - Anandasankar Ray
- Interdepartmental Neuroscience Program, University of California, Riverside, CA 92521, USA; Department of Molecular, Cell and Systems Biology, University of California, 3401 Watkins Drive, Riverside, CA 92521, USA.
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104
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Zak JD, Reddy G, Vergassola M, Murthy VN. Antagonistic odor interactions in olfactory sensory neurons are widespread in freely breathing mice. Nat Commun 2020; 11:3350. [PMID: 32620767 PMCID: PMC7335155 DOI: 10.1038/s41467-020-17124-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 06/10/2020] [Indexed: 12/24/2022] Open
Abstract
Odor landscapes contain complex blends of molecules that each activate unique, overlapping populations of olfactory sensory neurons (OSNs). Despite the presence of hundreds of OSN subtypes in many animals, the overlapping nature of odor inputs may lead to saturation of neural responses at the early stages of stimulus encoding. Information loss due to saturation could be mitigated by normalizing mechanisms such as antagonism at the level of receptor-ligand interactions, whose existence and prevalence remains uncertain. By imaging OSN axon terminals in olfactory bulb glomeruli as well as OSN cell bodies within the olfactory epithelium in freely breathing mice, we find widespread antagonistic interactions in binary odor mixtures. In complex mixtures of up to 12 odorants, antagonistic interactions are stronger and more prevalent with increasing mixture complexity. Therefore, antagonism is a common feature of odor mixture encoding in OSNs and helps in normalizing activity to reduce saturation and increase information transfer.
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Affiliation(s)
- Joseph D Zak
- Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, 02138, USA.
- Center for Brain Science, Harvard University, Cambridge, MA, 02138, USA.
| | - Gautam Reddy
- NSF-Simons Center for Mathematical & Statistical Analysis of Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Massimo Vergassola
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, Paris, F-75005, France
| | - Venkatesh N Murthy
- Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, 02138, USA.
- Center for Brain Science, Harvard University, Cambridge, MA, 02138, USA.
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105
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Exploring the Characteristics of an Aroma-Blending Mixture by Investigating the Network of Shared Odors and the Molecular Features of Their Related Odorants. Molecules 2020; 25:molecules25133032. [PMID: 32630789 PMCID: PMC7411594 DOI: 10.3390/molecules25133032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 11/16/2022] Open
Abstract
The perception of aroma mixtures is based on interactions beginning at the peripheral olfactory system, but the process remains poorly understood. The perception of a mixture of ethyl isobutyrate (Et-iB, strawberry-like odor) and ethyl maltol (Et-M, caramel-like odor) was investigated previously in both human and animal studies. In those studies, the binary mixture of Et-iB and Et-M was found to be configurally processed. In humans, the mixture was judged as more typical of a pineapple odor, similar to allyl hexanoate (Al-H, pineapple-like odor), than the odors of the individual components. To explore the key features of this aroma blend, we developed an in silico approach based on molecules having at least one of the odors—strawberry, caramel or pineapple. A dataset of 293 molecules and their related odors was built. We applied the notion of a “social network” to describe the network of the odors. Additionally, we explored the structural properties of the molecules in this dataset. The network of the odors revealed peculiar links between odors, while the structural study emphasized key characteristics of the molecules. The association between “strawberry” and “caramel” notes, as well as the structural diversity of the “strawberry” molecules, were notable. Such elements would be key to identifying potential odors/odorants to form aroma blends.
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106
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Pashkovski SL, Iurilli G, Brann D, Chicharro D, Drummey K, Franks KM, Panzeri S, Datta SR. Structure and flexibility in cortical representations of odour space. Nature 2020; 583:253-258. [PMID: 32612230 PMCID: PMC7450987 DOI: 10.1038/s41586-020-2451-1] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 04/02/2020] [Indexed: 02/08/2023]
Abstract
The cortex organizes sensory information to enable discrimination and generalization1-4. As systematic representations of chemical odour space have not yet been described in the olfactory cortex, it remains unclear how odour relationships are encoded to place chemically distinct but similar odours, such as lemon and orange, into perceptual categories, such as citrus5-7. Here, by combining chemoinformatics and multiphoton imaging in the mouse, we show that both the piriform cortex and its sensory inputs from the olfactory bulb represent chemical odour relationships through correlated patterns of activity. However, cortical odour codes differ from those in the bulb: cortex more strongly clusters together representations for related odours, selectively rewrites pairwise odour relationships, and better matches odour perception. The bulb-to-cortex transformation depends on the associative network originating within the piriform cortex, and can be reshaped by passive odour experience. Thus, cortex actively builds a structured representation of chemical odour space that highlights odour relationships; this representation is similar across individuals but remains plastic, suggesting a means through which the olfactory system can assign related odour cues to common and yet personalized percepts.
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Affiliation(s)
| | - Giuliano Iurilli
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Center for Neuroscience and Cognitive Systems, Istituto Italiano di Tecnologia, Rovereto, Italy
| | - David Brann
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Daniel Chicharro
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Neural Computation Laboratory, Istituto Italiano di Tecnologia, Rovereto, Italy
| | - Kristen Drummey
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Kevin M Franks
- Department of Neurobiology, Duke University, Durham, NC, USA
| | - Stefano Panzeri
- Neural Computation Laboratory, Istituto Italiano di Tecnologia, Rovereto, Italy
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107
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Makeyeva Y, Nicol C, Ledger WL, Ryugo DK. Immunocytochemical Localization of Olfactory-signaling Molecules in Human and Rat Spermatozoa. J Histochem Cytochem 2020; 68:491-513. [PMID: 32603211 DOI: 10.1369/0022155420939833] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Expression of olfactory receptors (ORs) in non-olfactory tissues has been widely reported over the last 20 years. Olfactory marker protein (OMP) is highly expressed in mature olfactory sensory neurons (mOSNs) of the olfactory epithelium. It is involved in the olfactory signal transduction pathway, which is mediated by well-conserved components, including ORs, olfactory G protein (Golf), and adenylyl cyclase 3 (AC3). OMP is widely expressed in non-olfactory tissues with an apparent preference for motile cells. We hypothesized that OMP is expressed in compartment-specific locations and co-localize with an OR, Golf, and AC3 in rat epididymal and human-ejaculated spermatozoa. We used immunocytochemistry to examine the expression patterns of OMP and OR6B2 (human OR, served as positive olfactory control) in experimentally induced modes of activation and determine whether there are any observable differences in proteins expression during the post-ejaculatory stages of spermatozoal functional maturation. We found that OMP was expressed in compartment-specific locations in human and rat spermatozoa. OMP was co-expressed with Golf and AC3 in rat spermatozoa and with OR6B2 in all three modes of activation (control, activated, and hyperactivated), and the mode of activation changed the co-expression pattern in acrosomal-reacted human spermatozoa. These observations suggest that OMP expression is a reliable indicator of OR-mediated chemoreception, may be used to identify ectopically expressed ORs, and could participate in second messenger signaling cascades that mediate fertility.
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Affiliation(s)
- Yuliya Makeyeva
- Garvan Institute of Medical Research, Royal Hospital for Women, Sydney, NSW, Australia.,Westfield Research Laboratories, School of Women's and Children's Health, Royal Hospital for Women, Sydney, NSW, Australia
| | - Christopher Nicol
- UNSW Sydney, Sydney, NSW, Australia, and Andrology Laboratory, NSW Health Pathology, Royal Hospital for Women, Sydney, NSW, Australia
| | - William L Ledger
- Fertility & Research Centre, Royal Hospital for Women, Sydney, NSW, Australia
| | - David K Ryugo
- Garvan Institute of Medical Research, Royal Hospital for Women, Sydney, NSW, Australia.,School of Medical Sciences, UNSW, Royal Hospital for Women, Sydney, NSW, Australia.,Department of Otolaryngology, Head, Neck & Skull Base Surgery, St. Vincent's Hospital, Royal Hospital for Women, Sydney, NSW, Australia
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108
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Haag F, Ahmed L, Reiss K, Block E, Batista VS, Krautwurst D. Copper-mediated thiol potentiation and mutagenesis-guided modeling suggest a highly conserved copper-binding motif in human OR2M3. Cell Mol Life Sci 2020; 77:2157-2179. [PMID: 31435697 PMCID: PMC7256108 DOI: 10.1007/s00018-019-03279-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 08/07/2019] [Accepted: 08/12/2019] [Indexed: 12/20/2022]
Abstract
Sulfur-containing compounds within a physiological relevant, natural odor space, such as the key food odorants, typically constitute the group of volatiles with the lowest odor thresholds. The observation that certain metals, such as copper, potentiate the smell of sulfur-containing, metal-coordinating odorants led to the hypothesis that their cognate receptors are metalloproteins. However, experimental evidence is sparse-so far, only one human odorant receptor, OR2T11, and a few mouse receptors, have been reported to be activated by sulfur-containing odorants in a copper-dependent way, while the activation of other receptors by sulfur-containing odorants did not depend on the presence of metals. Here we identified an evolutionary conserved putative copper interaction motif CC/CSSH, comprising two copper-binding sites in TMH5 and TMH6, together with the binding pocket for 3-mercapto-2-methylpentan-1-ol in the narrowly tuned human receptor OR2M3. To characterize the copper-binding motif, we combined homology modeling, docking studies, site-directed mutagenesis, and functional expression of recombinant ORs in a cell-based, real-time luminescence assay. Ligand activation of OR2M3 was potentiated in the presence of copper. This effect of copper was mimicked by ionic and colloidal silver. In two broadly tuned receptors, OR1A1 and OR2W1, which did not reveal a putative copper interaction motif, activation by their most potent, sulfur-containing key food odorants did not depend on the presence of copper. Our results suggest a highly conserved putative copper-binding motif to be necessary for a copper-modulated and thiol-specific function of members from three subfamilies of family 2 ORs.
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Affiliation(s)
- Franziska Haag
- Leibniz-Institute for Food Systems Biology, Technical University of Munich, Lise-Meitner-Str. 34, 85354, Freising, Germany
| | - Lucky Ahmed
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Krystle Reiss
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Eric Block
- Department of Chemistry, University at Albany, State University of New York, Albany, NY, 12222, USA
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Dietmar Krautwurst
- Leibniz-Institute for Food Systems Biology, Technical University of Munich, Lise-Meitner-Str. 34, 85354, Freising, Germany.
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109
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Hu XS, Ikegami K, Vihani A, Zhu KW, Zapata M, de March CA, Do M, Vaidya N, Kucera G, Bock C, Jiang Y, Yohda M, Matsunami H. Concentration-Dependent Recruitment of Mammalian Odorant Receptors. eNeuro 2020; 7:ENEURO.0103-19.2019. [PMID: 32015097 PMCID: PMC7189481 DOI: 10.1523/eneuro.0103-19.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 11/22/2019] [Accepted: 11/26/2019] [Indexed: 12/20/2022] Open
Abstract
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.
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Affiliation(s)
- Xiaoyang Serene Hu
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Kentaro Ikegami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
- Tokyo University of Agriculture and Technology, Tokyo 183-8538, Japan
| | - Aashutosh Vihani
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
- Department of Neurobiology, Duke Institute for Brain Sciences, Duke University, Durham, NC 27710
| | - Kevin W Zhu
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Marcelo Zapata
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Claire A de March
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Matthew Do
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Natasha Vaidya
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
- North Carolina School of Science and Mathematics, Durham, NC 27705
| | - Gary Kucera
- DCI Rodent Cancer Models Shared Resource, Duke University Medical Center, Durham, NC 27710
| | - Cheryl Bock
- DCI Rodent Cancer Models Shared Resource, Duke University Medical Center, Durham, NC 27710
| | - Yue Jiang
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Masafumi Yohda
- Tokyo University of Agriculture and Technology, Tokyo 183-8538, Japan
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710
- Department of Neurobiology, Duke Institute for Brain Sciences, Duke University, Durham, NC 27710
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110
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Jae Y, Lee N, Moon DW, Koo J. Interhemispheric asymmetry of c-Fos expression in glomeruli and the olfactory tubercle following repeated odor stimulation. FEBS Open Bio 2020; 10:912-926. [PMID: 32237058 PMCID: PMC7193154 DOI: 10.1002/2211-5463.12851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/26/2020] [Accepted: 03/26/2020] [Indexed: 11/09/2022] Open
Abstract
Odor adaptation allows the olfactory system to regulate sensitivity to different stimulus intensities, which is essential for preventing saturation of the cell‐transducing machinery and maintaining high sensitivity to persistent and repetitive odor stimuli. Although many studies have investigated the structure and mechanisms of the mammalian olfactory system that responds to chemical sensation, few studies have considered differences in neuronal activation that depend on the manner in which the olfactory system is exposed to odorants, or examined activity patterns of olfactory‐related regions in the brain under different odor exposure conditions. To address these questions, we designed three different odor exposure conditions that mimicked diverse odor environments and analyzed c‐Fos‐expressing cells (c‐Fos+ cells) in the odor columns of the olfactory bulb (OB). We then measured differences in the proportions of c‐Fos‐expressing cell types depending on the odor exposure condition. Surprisingly, under the specific odor condition in which the olfactory system was repeatedly exposed to the odorant for 1 min at 5‐min intervals, one of the lateral odor columns and the ipsilateral hemisphere of the olfactory tubercle had more c‐Fos+ cells than the other three odor columns and the contralateral hemisphere of the olfactory tubercle. However, this interhemispheric asymmetry of c‐Fos expression was not observed in the anterior piriform cortex. To confirm whether the anterior olfactory nucleus pars externa (AONpE), which connects the left and right OB, contributes to this asymmetry, AONpE‐lesioned mice were analyzed under the specific odor exposure condition. Asymmetric c‐Fos expression was not observed in the OB or the olfactory tubercle. These data indicate that the c‐Fos expression patterns of the olfactory‐related regions in the brain are influenced by the odor exposure condition and that asymmetric c‐Fos expression in these regions was observed under a specific odor exposure condition due to synaptic linkage via the AONpE.
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Affiliation(s)
- YoonGyu Jae
- Department of Brain and Cognitive Sciences, DGIST, Daegu, Korea
| | - NaHye Lee
- Department of Brain and Cognitive Sciences, DGIST, Daegu, Korea
| | | | - JaeHyung Koo
- Department of New Biology, DGIST, Daegu, Korea.,Center for Bio-Convergence Spin System, DGIST, Daegu, Korea
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111
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Freeman AR, Ophir AG, Sheehan MJ. The giant pouched rat (Cricetomys ansorgei) olfactory receptor repertoire. PLoS One 2020; 15:e0221981. [PMID: 32240170 PMCID: PMC7117715 DOI: 10.1371/journal.pone.0221981] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 03/06/2020] [Indexed: 12/12/2022] Open
Abstract
For rodents, olfaction is essential for locating food, recognizing mates and competitors, avoiding predators, and navigating their environment. It is thought that rodents may have expanded olfactory receptor repertoires in order to specialize in olfactory behavior. Despite being the largest clade of mammals and depending on olfaction relatively little work has documented olfactory repertoires outside of conventional laboratory species. Here we report the olfactory receptor repertoire of the African giant pouched rat (Cricetomys ansorgei), a Muroid rodent distantly related to mice and rats. The African giant pouched rat is notable for its large cortex and olfactory bulbs relative to its body size compared to other sympatric rodents, which suggests anatomical elaboration of olfactory capabilities. We hypothesized that in addition to anatomical elaboration for olfaction, these pouched rats might also have an expanded olfactory receptor repertoire to enable their olfactory behavior. We examined the composition of the olfactory receptor repertoire to better understand how their sensory capabilities have evolved. We identified 1145 intact olfactory genes, and 260 additional pseudogenes within 301 subfamilies from the African giant pouched rat genome. This repertoire is similar to mice and rats in terms of size, pseudogene percentage and number of subfamilies. Analyses of olfactory receptor gene trees revealed that the pouched rat has 6 expansions in different subfamilies compared to mice, rats and squirrels. We identified 81 orthologous genes conserved among 4 rodent species and an additional 147 conserved genes within the Muroid rodents. The orthologous genes shared within Muroidea suggests that there may be a conserved Muroid-specific olfactory receptor repertoire. We also note that the description of this repertoire can serve as a complement to other studies of rodent olfaction, as the pouched rat is an outgroup within Muroidea. Thus, our data suggest that African giant pouched rats are capable of both natural and trained olfactory behaviors with a typical Muriod olfactory receptor repertoire.
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Affiliation(s)
- Angela R. Freeman
- Department of Psychology, Cornell University, Ithaca, NY, United States of America
- * E-mail:
| | - Alexander G. Ophir
- Department of Psychology, Cornell University, Ithaca, NY, United States of America
| | - Michael J. Sheehan
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, United States of America
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112
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Jodat YA, Kiaee K, Vela Jarquin D, De la Garza Hernández RL, Wang T, Joshi S, Rezaei Z, de Melo BAG, Ge D, Mannoor MS, Shin SR. A 3D-Printed Hybrid Nasal Cartilage with Functional Electronic Olfaction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:1901878. [PMID: 32154068 PMCID: PMC7055567 DOI: 10.1002/advs.201901878] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/18/2019] [Indexed: 05/05/2023]
Abstract
Advances in biomanufacturing techniques have opened the doors to recapitulate human sensory organs such as the nose and ear in vitro with adequate levels of functionality. Such advancements have enabled simultaneous targeting of two challenges in engineered sensory organs, especially the nose: i) mechanically robust reconstruction of the nasal cartilage with high precision and ii) replication of the nose functionality: odor perception. Hybrid nasal organs can be equipped with remarkable capabilities such as augmented olfactory perception. Herein, a proof-of-concept for an odor-perceptive nose-like hybrid, which is composed of a mechanically robust cartilage-like construct and a biocompatible biosensing platform, is proposed. Specifically, 3D cartilage-like tissue constructs are created by multi-material 3D bioprinting using mechanically tunable chondrocyte-laden bioinks. In addition, by optimizing the composition of stiff and soft bioinks in macro-scale printed constructs, the competence of this system in providing improved viability and recapitulation of chondrocyte cell behavior in mechanically robust 3D constructs is demonstrated. Furthermore, the engineered cartilage-like tissue construct is integrated with an electrochemical biosensing system to bring functional olfactory sensations toward multiple specific airway disease biomarkers, explosives, and toxins under biocompatible conditions. Proposed hybrid constructs can lay the groundwork for functional bionic interfaces and humanoid cyborgs.
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Affiliation(s)
- Yasamin A. Jodat
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- Department of Mechanical EngineeringStevens Institute of TechnologyHobokenNJ07030USA
| | - Kiavash Kiaee
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- Department of Mechanical EngineeringStevens Institute of TechnologyHobokenNJ07030USA
| | - Daniel Vela Jarquin
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- Instituto Tecnológico y de Estudios Superiores de MonterreyCalle del Puente #222 Col. Ejidos de Huipulco, Tlalpan C.P.14380MéxicoD.F.Mexico
| | - Rosakaren Ludivina De la Garza Hernández
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- Instituto Tecnológico y de Estudios Superiores de MonterreyAv. Eugenio Garza Sada 2501 Sur, Tecnológico64849MonterreyN.L.Mexico
| | - Ting Wang
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- School of MedicineJiangsu UniversityZhenjiangJiangsu212013China
| | - Sudeep Joshi
- Department of Mechanical EngineeringStevens Institute of TechnologyHobokenNJ07030USA
| | - Zahra Rezaei
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- Department of Chemical and Petroleum EngineeringSharif University of TechnologyAzadi Ave11365‐11155TehranIran
| | - Bruna Alice Gomes de Melo
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
- Department of Engineering of Materials and BioprocessesSchool of Chemical EngineeringUniversity of CampinasCampinasSão Paulo13083‐852Brazil
| | - David Ge
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
| | - Manu S. Mannoor
- Department of Mechanical EngineeringStevens Institute of TechnologyHobokenNJ07030USA
| | - Su Ryon Shin
- Division of Engineering in MedicineDepartment of MedicineHarvard Medical SchoolBrigham and Women's HospitalCambridgeMA02139USA
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113
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Kotlo K, Anbazhagan AN, Priyamvada S, Jayawardena D, Kumar A, Chen Y, Xia Y, Finn PW, Perkins DL, Dudeja PK, Layden BT. The olfactory G protein-coupled receptor (Olfr-78/OR51E2) modulates the intestinal response to colitis. Am J Physiol Cell Physiol 2020; 318:C502-C513. [PMID: 31913697 PMCID: PMC7099522 DOI: 10.1152/ajpcell.00454.2019] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/02/2019] [Accepted: 12/19/2019] [Indexed: 12/27/2022]
Abstract
Olfactory receptor-78 (Olfr-78) is a recently identified G protein-coupled receptor activated by short-chain fatty acids acetate and propionate. A suggested role for this receptor exists in the prostate where it may influence chronic inflammatory response leading to intraepithelial neoplasia. Olfr-78 has also been shown to be expressed in mouse colon. Short-chain fatty acids and their receptors are well known to modulate inflammation in the gut. Considering this possibility, we first explored if colitis regulated Olfr-78 expression in the gut, where we observed a significant reduction in the expression of Olfr-78 transcript in mouse models of dextran sodium sulfate (DSS)- and 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. To more directly test this, mice deficient in Olfr-78 were administered with DSS in water for 7 days and were found to have increased expression of IL-1β and inflammatory signs in colon compared with control mice. Next, we explored the expression of its human counterpart olfactory receptor family 51, subfamily E, member 2 (OR51E2) in human intestinal samples and observed that it was in fact also expressed in human colon samples. RNA sequence analysis revealed significant changes in the genes involved in infection, immunity, inflammation, and colorectal cancer between wild-type and Olfr-78 knockout mice. Collectively, our findings show that Olfr-78 is highly expressed in colon and downregulated in DSS- and TNBS-induced colitis, and DSS-treated Olfr-78 null mice had increased colonic expression of cytokine RNA levels, suggesting a potential role for this receptor in intestinal inflammation. Future investigations are needed to understand how Olfr-78/OR51E2 in both mouse and human intestine modulates gastrointestinal pathophysiology.
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Affiliation(s)
- Kumar Kotlo
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Dulari Jayawardena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anoop Kumar
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Yang Chen
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois
- Division of Pulmonary, Critical Care, Sleep, and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Yinglin Xia
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Patricia W Finn
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
- Division of Pulmonary, Critical Care, Sleep, and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Department of Microbiology/Immunology, University of Illinois at Chicago, Chicago, Illinois
| | - David L Perkins
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
- Division of Nephrology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Department of Surgery, University of Illinois at Chicago, Chicago, Illinois
| | - Pradeep K Dudeja
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinoi
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Brian T Layden
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinoi
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
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114
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de March CA, Titlow WB, Sengoku T, Breheny P, Matsunami H, McClintock TS. Modulation of the combinatorial code of odorant receptor response patterns in odorant mixtures. Mol Cell Neurosci 2020; 104:103469. [PMID: 32061665 DOI: 10.1016/j.mcn.2020.103469] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 02/01/2023] Open
Abstract
The perception of odors relies on combinatorial codes consisting of odorant receptor (OR) response patterns to encode odor identity. Modulation of these patterns by odorant interactions at ORs potentially explains several olfactory phenomena: mixture suppression, unpredictable sensory outcomes, and the perception of odorant mixtures as unique objects. We determined OR response patterns to 4 odorants and 3 binary mixtures in vivo in mice, identifying 30 responsive ORs. These patterns typically had a few strongly responsive ORs and a greater number of weakly responsive ORs. ORs responsive to an odorant were often unrelated sequences distributed across several OR subfamilies. Mixture responses predicted pharmacological interactions between odorants, which were tested in vitro by heterologous expression of ORs in cultured cells, providing independent evidence confirming odorant agonists for 13 ORs and identifying both suppressive and additive effects. This included 11 instances of antagonism of ORs by an odorant, 1 instance of additive responses to a binary mixture, 1 instance of suppression of a strong agonist by a weak agonist, and the discovery of an inverse agonist for an OR. Interactions between odorants at ORs are common even when the odorants are not known to interact perceptually in humans, and in some cases interactions at mouse ORs correlate with the ability of humans to perceive an odorant in a mixture.
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Affiliation(s)
- Claire A de March
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - William B Titlow
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Tomoko Sengoku
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Patrick Breheny
- Department of Biostatistics, University of Iowa, Iowa City, IA 52242, USA
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA; Department of Neurobiology, Duke University School of Medicine, Durham, NC 27710, USA; Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan; Duke Institute for Brain Sciences, Duke University, Durham, NC 27710, USA.
| | - Timothy S McClintock
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA.
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115
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Soelter J, Schumacher J, Spors H, Schmuker M. Computational exploration of molecular receptive fields in the olfactory bulb reveals a glomerulus-centric chemical map. Sci Rep 2020; 10:77. [PMID: 31919393 PMCID: PMC6952415 DOI: 10.1038/s41598-019-56863-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 09/24/2019] [Indexed: 01/13/2023] Open
Abstract
Progress in olfactory research is currently hampered by incomplete knowledge about chemical receptive ranges of primary receptors. Moreover, the chemical logic underlying the arrangement of computational units in the olfactory bulb has still not been resolved. We undertook a large-scale approach at characterising molecular receptive ranges (MRRs) of glomeruli in the dorsal olfactory bulb (dOB) innervated by the MOR18-2 olfactory receptor, also known as Olfr78, with human ortholog OR51E2. Guided by an iterative approach that combined biological screening and machine learning, we selected 214 odorants to characterise the response of MOR18-2 and its neighbouring glomeruli. We found that a combination of conventional physico-chemical and vibrational molecular descriptors performed best in predicting glomerular responses using nonlinear Support-Vector Regression. We also discovered several previously unknown odorants activating MOR18-2 glomeruli, and obtained detailed MRRs of MOR18-2 glomeruli and their neighbours. Our results confirm earlier findings that demonstrated tunotopy, that is, glomeruli with similar tuning curves tend to be located in spatial proximity in the dOB. In addition, our results indicate chemotopy, that is, a preference for glomeruli with similar physico-chemical MRR descriptions being located in spatial proximity. Together, these findings suggest the existence of a partial chemical map underlying glomerular arrangement in the dOB. Our methodology that combines machine learning and physiological measurements lights the way towards future high-throughput studies to deorphanise and characterise structure-activity relationships in olfaction.
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Affiliation(s)
- Jan Soelter
- Neuroinformatics & Theoretical Neuroscience, Freie Universität Berlin, Königin-Luise-Str. 1-3, 14195, Berlin, Germany
| | - Jan Schumacher
- Max-Planck-Institute for Biophysics, Max-von-Laue-Str. 3, 60438, Frankfurt/Main, Germany
| | - Hartwig Spors
- Max-Planck-Institute for Biophysics, Max-von-Laue-Str. 3, 60438, Frankfurt/Main, Germany
- Department of Neuropediatrics, Max-Liebig-University, Giessen, Germany
| | - Michael Schmuker
- Neuroinformatics & Theoretical Neuroscience, Freie Universität Berlin, Königin-Luise-Str. 1-3, 14195, Berlin, Germany.
- Biocomputation Group, University of Hertfordshire, Hatfield, AL10 9AB, United Kingdom.
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116
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Cho SW, Park TH. Comparative Evaluation of Sensitivity to Hexanal Between Human and Canine Olfactory Receptors. BIOTECHNOL BIOPROC E 2019. [DOI: 10.1007/s12257-019-0265-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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117
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Liu A, He F, Shen L, Liu R, Wang Z, Zhou J. Convergent degeneration of olfactory receptor gene repertoires in marine mammals. BMC Genomics 2019; 20:977. [PMID: 31842731 PMCID: PMC6916060 DOI: 10.1186/s12864-019-6290-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 11/14/2019] [Indexed: 11/10/2022] Open
Abstract
Background Olfactory receptors (ORs) can bind odor molecules and play a crucial role in odor sensation. Due to the frequent gains and losses of genes during evolution, the number of OR members varies greatly among different species. However, whether the extent of gene gains/losses varies between marine mammals and related terrestrial mammals has not been clarified, and the factors that might underlie these variations are unknown. Results To address these questions, we identified more than 10,000 members of the OR family in 23 mammals and classified them into 830 orthologous gene groups (OGGs) and 281 singletons. Significant differences occurred in the number of OR repertoires and OGGs among different species. We found that all marine mammals had fewer OR genes than their related terrestrial lineages, with the fewest OR genes found in cetaceans, which may be closely related to olfactory degradation. ORs with more gene duplications or loss events tended to be under weaker purifying selection. The average gain and loss rates of OR genes in terrestrial mammals were higher than those of mammalian gene families, while the average gain and loss rates of OR genes in marine mammals were significantly lower and much higher than those of mammalian gene families, respectively. Additionally, we failed to detect any one-to-one orthologous genes in the focal species, suggesting that OR genes are not well conserved among marine mammals. Conclusions Marine mammals have experienced large numbers of OR gene losses compared with their related terrestrial lineages, which may result from the frequent birth-and-death evolution under varied functional constrains. Due to their independent degeneration, OR genes present in each lineage are not well conserved among marine mammals. Our study provides a basis for future research on the olfactory receptor function in mammals from the perspective of evolutionary trajectories.
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Affiliation(s)
- Ake Liu
- Faculty of Biological Science and Technology, Changzhi University, Changzhi, Shanxi, 046011, People's Republic of China.,School of Life Sciences, Fudan University, Shanghai, 200438, People's Republic of China
| | - Funan He
- School of Life Sciences, Fudan University, Shanghai, 200438, People's Republic of China
| | - Libing Shen
- Institute of Neuroscience, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, People's Republic of China
| | - Ruixiang Liu
- Faculty of Biological Science and Technology, Changzhi University, Changzhi, Shanxi, 046011, People's Republic of China
| | - Zhijun Wang
- Department of Chemistry, Changzhi University, Changzhi, Shanxi, 046011, People's Republic of China.
| | - Jingqi Zhou
- School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People's Republic of China.
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118
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Chepurwar S, Gupta A, Haddad R, Gupta N. Sequence-Based Prediction of Olfactory Receptor Responses. Chem Senses 2019; 44:693-703. [PMID: 31665762 DOI: 10.1093/chemse/bjz059] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Computational prediction of how strongly an olfactory receptor (OR) responds to various odors can help in bridging the widening gap between the large number of receptors that have been sequenced and the small number of experiments measuring their responses. Previous efforts in this area have predicted the responses of a receptor to some odors, using the known responses of the same receptor to other odors. Here, we present a method to predict the responses of a receptor without any known responses by using available data about the responses of other conspecific receptors and their sequences. We applied this method to ORs in insects Drosophila melanogaster (both adult and larva) and Anopheles gambiae and to mouse and human ORs. We found the predictions to be in significant agreement with the experimental measurements. The method also provides clues about the response-determining positions within the receptor sequences.
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Affiliation(s)
- Shashank Chepurwar
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
| | - Abhishek Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India.,Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
| | - Rafi Haddad
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel
| | - Nitin Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
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119
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Coppola DM, Fitzwater E, Rygg AD, Craven BA. Tests of the chromatographic theory of olfaction with highly soluble odors: a combined electro-olfactogram and computational fluid dynamics study in the mouse. Biol Open 2019; 8:bio.047217. [PMID: 31649069 PMCID: PMC6826284 DOI: 10.1242/bio.047217] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The idea that the vertebrate nasal cavity operates like a gas chromatograph to separate and discriminate odors, referred to herein as the ‘chromatographic theory’ (CT), has a long and interesting history. Though the last decade has seen renewed interest in the notion, its validity remains in question. Here we examine a necessary condition of the theory: a correlation between nasal odor deposition patterns based on mucus solubility and the distribution of olfactory sensory neuron odotypes. Our recent work in the mouse failed to find such a relationship even across large sorption gradients within the olfactory epithelium (OE). However, these studies did not test extremely soluble odorants or low odor concentrations, factors that could explain our inability to find supporting evidence for the CT. The current study combined computational fluid dynamics (CFD) simulations of odor sorption patterns and electro-olfactogram (EOG) measurements of olfactory sensory neuron responses. The odorants tested were at the extremes of mucus solubility and at a range of concentrations. Results showed no relationship between local odor sorption patterns and EOG response maps. Together, results again failed to support a necessary condition of the CT casting further doubt on the viability of this classical odor coding mechanism. Summary: This paper casts doubt on the classical chromatographic theory of olfaction, showing there is no correlation between olfactory receptor spatial layout and odor solubility patterns, a necessary condition of the theory.
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Affiliation(s)
- David M Coppola
- Department of Biology, Randolph-Macon College, Ashland, VA 23005, USA
| | - Emily Fitzwater
- Department of Biology, Randolph-Macon College, Ashland, VA 23005, USA
| | - Alex D Rygg
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA 90095, USA
| | - Brent A Craven
- Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802, USA
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120
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Qin S, Li Q, Tang C, Tu Y. Optimal compressed sensing strategies for an array of nonlinear olfactory receptor neurons with and without spontaneous activity. Proc Natl Acad Sci U S A 2019; 116:20286-20295. [PMID: 31548382 PMCID: PMC6789560 DOI: 10.1073/pnas.1906571116] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
There are numerous different odorant molecules in nature but only a relatively small number of olfactory receptor neurons (ORNs) in brains. This "compressed sensing" challenge is compounded by the constraint that ORNs are nonlinear sensors with a finite dynamic range. Here, we investigate possible optimal olfactory coding strategies by maximizing mutual information between odor mixtures and ORNs' responses with respect to the bipartite odor-receptor interaction network (ORIN) characterized by sensitivities between all odorant-ORN pairs. For ORNs without spontaneous (basal) activity, we find that the optimal ORIN is sparse-a finite fraction of sensitives are zero, and the nonzero sensitivities follow a broad distribution that depends on the odor statistics. We show analytically that sparsity in the optimal ORIN originates from a trade-off between the broad tuning of ORNs and possible interference. Furthermore, we show that the optimal ORIN enhances performances of downstream learning tasks (reconstruction and classification). For ORNs with a finite basal activity, we find that having inhibitory odor-receptor interactions increases the coding capacity and the fraction of inhibitory interactions increases with the ORN basal activity. We argue that basal activities in sensory receptors in different organisms are due to the trade-off between the increase in coding capacity and the cost of maintaining the spontaneous basal activity. Our theoretical findings are consistent with existing experiments and predictions are made to further test our theory. The optimal coding model provides a unifying framework to understand the peripheral olfactory systems across different organisms.
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Affiliation(s)
- Shanshan Qin
- Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Qianyi Li
- Integrated Science Program, Yuanpei College, Peking University, Beijing 100871, China
| | - Chao Tang
- Center for Quantitative Biology, Peking University, Beijing 100871, China;
- School of Physics, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yuhai Tu
- Physical Sciences Department, IBM T. J. Watson Research Center, Yorktown Heights, NY 10598
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121
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Fukutani Y, Tamaki R, Inoue R, Koshizawa T, Sakashita S, Ikegami K, Ohsawa I, Matsunami H, Yohda M. The N-terminal region of RTP1S plays important roles in dimer formation and odorant receptor-trafficking. J Biol Chem 2019; 294:14661-14673. [PMID: 31395660 PMCID: PMC6779431 DOI: 10.1074/jbc.ra118.007110] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 07/30/2019] [Indexed: 12/31/2022] Open
Abstract
Receptor-transporting protein 1S (RTP1S) is an accessory protein that mediates the transport of mammalian odorant receptors (ORs) into the plasma membrane. Although most ORs fail to localize to the cell surface when expressed alone in nonolfactory cells, functional expression of ORs is achieved with the coexpression of RTP1S. However, the mechanism for RTP1S-mediated OR trafficking remains unclear. In this study, we attempted to reveal the mode of action and critical residues of RTP1S in OR trafficking. Experiments using N-terminal truncation and Ala substitution mutants of RTP1S demonstrated that four N-terminal amino acids have essential roles in OR trafficking. Additionally, using recombinant proteins and split luciferase assays in mammalian cells, we provided evidence for the dimer formation of RTP1S. Furthermore, we determined that the 2nd Cys residue is required for the efficient dimerization of RTP1S. Altogether, these findings provide insights into the mechanism for plasma membrane transport of ORs by RTP1S.
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Affiliation(s)
- Yosuke Fukutani
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.,Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Ryohei Tamaki
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Ryosuke Inoue
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Tomoyo Koshizawa
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Shuto Sakashita
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Kentaro Ikegami
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Ikuroh Ohsawa
- Biological Process of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo 173-0015, Japan
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710.,Department of Neurobiology, Duke Institute for Brain Sciences, Duke University Medical Center, Durham, North Carolina 27705.,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Masafumi Yohda
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan .,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
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122
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Cichy A, Shah A, Dewan A, Kaye S, Bozza T. Genetic Depletion of Class I Odorant Receptors Impacts Perception of Carboxylic Acids. Curr Biol 2019; 29:2687-2697.e4. [PMID: 31378611 DOI: 10.1016/j.cub.2019.06.085] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/28/2019] [Accepted: 06/28/2019] [Indexed: 12/20/2022]
Abstract
The mammalian main olfactory pathway detects myriad volatile chemicals using >1,000 odorant receptor (OR) genes, which are organized into two phylogenetically distinct classes (class I and class II). An important question is how these evolutionarily conserved classes contribute to odor perception. Here, we report functional inactivation of a large number of class I ORs in mice via identification and deletion of a local cis-acting enhancer in the class I gene cluster. This manipulation reduced expression of half of the 131 intact class I genes. The resulting class I-depleted mice exhibited a significant reduction in the number of glomeruli responding to carboxylic acids-chemicals associated with microbial action and body odors. These mice also exhibit a change in odor perception marked by a selective loss of behavioral aversion to these compounds. Together, our data demonstrate that class I ORs play a critical role in representing a class of biologically relevant chemosignals.
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Affiliation(s)
- Annika Cichy
- Department of Neurobiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Ami Shah
- Department of Neurobiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Adam Dewan
- Department of Neurobiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Sarah Kaye
- Department of Neurobiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Thomas Bozza
- Department of Neurobiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA.
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123
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Gómez-Baena G, Armstrong SD, Halstead JO, Prescott M, Roberts SA, McLean L, Mudge JM, Hurst JL, Beynon RJ. Molecular complexity of the major urinary protein system of the Norway rat, Rattus norvegicus. Sci Rep 2019; 9:10757. [PMID: 31341188 PMCID: PMC6656916 DOI: 10.1038/s41598-019-46950-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 07/03/2019] [Indexed: 01/19/2023] Open
Abstract
Major urinary proteins (MUP) are the major component of the urinary protein fraction in house mice (Mus spp.) and rats (Rattus spp.). The structure, polymorphism and functions of these lipocalins have been well described in the western European house mouse (Mus musculus domesticus), clarifying their role in semiochemical communication. The complexity of these roles in the mouse raises the question of similar functions in other rodents, including the Norway rat, Rattus norvegicus. Norway rats express MUPs in urine but information about specific MUP isoform sequences and functions is limited. In this study, we present a detailed molecular characterization of the MUP proteoforms expressed in the urine of two laboratory strains, Wistar Han and Brown Norway, and wild caught animals, using a combination of manual gene annotation, intact protein mass spectrometry and bottom-up mass spectrometry-based proteomic approaches. Cluster analysis shows the existence of only 10 predicted mup genes. Further, detailed sequencing of the urinary MUP isoforms reveals a less complex pattern of primary sequence polymorphism in the rat than the mouse. However, unlike the mouse, rat MUPs exhibit added complexity in the form of post-translational modifications, including the phosphorylation of Ser4 in some isoforms, and exoproteolytic trimming of specific isoforms. Our results raise the possibility that urinary MUPs may have different roles in rat chemical communication than those they play in the house mouse. Shotgun proteomics data are available via ProteomExchange with identifier PXD013986.
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Affiliation(s)
- Guadalupe Gómez-Baena
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Crown Street, L697ZB, Liverpool, United Kingdom
| | - Stuart D Armstrong
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Crown Street, L697ZB, Liverpool, United Kingdom
| | - Josiah O Halstead
- Mammalian Behaviour and Evolution Group, University of Liverpool, Leahurst Campus, Neston, United Kingdom
| | - Mark Prescott
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Crown Street, L697ZB, Liverpool, United Kingdom
| | - Sarah A Roberts
- Mammalian Behaviour and Evolution Group, University of Liverpool, Leahurst Campus, Neston, United Kingdom
| | - Lynn McLean
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Crown Street, L697ZB, Liverpool, United Kingdom
| | - Jonathan M Mudge
- EMBL-EBI, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, United Kingdom
| | - Jane L Hurst
- Mammalian Behaviour and Evolution Group, University of Liverpool, Leahurst Campus, Neston, United Kingdom
| | - Robert J Beynon
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Crown Street, L697ZB, Liverpool, United Kingdom.
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124
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Chae H, Kepple DR, Bast WG, Murthy VN, Koulakov AA, Albeanu DF. Mosaic representations of odors in the input and output layers of the mouse olfactory bulb. Nat Neurosci 2019; 22:1306-1317. [PMID: 31332371 DOI: 10.1038/s41593-019-0442-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 05/30/2019] [Indexed: 11/09/2022]
Abstract
The elementary stimulus features encoded by the olfactory system remain poorly understood. We examined the relationship between 1,666 physical-chemical descriptors of odors and the activity of olfactory bulb inputs and outputs in awake mice. Glomerular and mitral and tufted cell responses were sparse and locally heterogeneous, with only a weak dependence of their positions on physical-chemical properties. Odor features represented by ensembles of mitral and tufted cells were overlapping but distinct from those represented in glomeruli, which is consistent with an extensive interplay between feedforward and feedback inputs to the bulb. This reformatting was well described as a rotation in odor space. The physical-chemical descriptors accounted for a small fraction in response variance, and the similarity of odors in the physical-chemical space was a poor predictor of similarity in neuronal representations. Our results suggest that commonly used physical-chemical properties are not systematically represented in bulbar activity and encourage further searches for better descriptors of odor space.
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Affiliation(s)
- Honggoo Chae
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Daniel R Kepple
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.,Watson School for Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Walter G Bast
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Venkatesh N Murthy
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Alexei A Koulakov
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA. .,Watson School for Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
| | - Dinu F Albeanu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA. .,Watson School for Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
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125
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Saraiva LR, Riveros-McKay F, Mezzavilla M, Abou-Moussa EH, Arayata CJ, Makhlouf M, Trimmer C, Ibarra-Soria X, Khan M, Van Gerven L, Jorissen M, Gibbs M, O’Flynn C, McGrane S, Mombaerts P, Marioni JC, Mainland JD, Logan DW. A transcriptomic atlas of mammalian olfactory mucosae reveals an evolutionary influence on food odor detection in humans. SCIENCE ADVANCES 2019; 5:eaax0396. [PMID: 31392275 PMCID: PMC6669018 DOI: 10.1126/sciadv.aax0396] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 06/24/2019] [Indexed: 05/07/2023]
Abstract
The mammalian olfactory system displays species-specific adaptations to different ecological niches. To investigate the evolutionary dynamics of olfactory sensory neuron (OSN) subtypes across mammalian evolution, we applied RNA sequencing of whole olfactory mucosa samples from mouse, rat, dog, marmoset, macaque, and human. We find that OSN subtypes, representative of all known mouse chemosensory receptor gene families, are present in all analyzed species. Further, we show that OSN subtypes expressing canonical olfactory receptors are distributed across a large dynamic range and that homologous subtypes can be either highly abundant across all species or species/order specific. Highly abundant mouse and human OSN subtypes detect odorants with similar sensory profiles and sense ecologically relevant odorants, such as mouse semiochemicals or human key food odorants. Together, our results allow for a better understanding of the evolution of mammalian olfaction in mammals and provide insights into the possible functions of highly abundant OSN subtypes.
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Affiliation(s)
- Luis R. Saraiva
- Sidra Medicine, PO Box 26999, Doha, Qatar
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
- European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Genome Campus, Hinxton,, Cambridge CB10 1SD, UK
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
| | | | | | | | | | | | - Casey Trimmer
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
| | - Ximena Ibarra-Soria
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Mona Khan
- Max Planck Research Unit for Neurogenetics, Max von-Laue-Strasse 4, 60438 Frankfurt, Germany
| | - Laura Van Gerven
- Department of ENT-HNS, UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Mark Jorissen
- Department of ENT-HNS, UZ Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Matthew Gibbs
- Waltham Centre for Pet Nutrition, Leicestershire LE14 4RT, UK
| | - Ciaran O’Flynn
- Waltham Centre for Pet Nutrition, Leicestershire LE14 4RT, UK
| | - Scott McGrane
- Waltham Centre for Pet Nutrition, Leicestershire LE14 4RT, UK
| | - Peter Mombaerts
- Max Planck Research Unit for Neurogenetics, Max von-Laue-Strasse 4, 60438 Frankfurt, Germany
| | - John C. Marioni
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
- European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Genome Campus, Hinxton,, Cambridge CB10 1SD, UK
- CRUK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, UK
| | - Joel D. Mainland
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
- Department of Neuroscience, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Darren W. Logan
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
- Waltham Centre for Pet Nutrition, Leicestershire LE14 4RT, UK
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126
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Halperin Kuhns VL, Sanchez J, Sarver DC, Khalil Z, Rajkumar P, Marr KA, Pluznick JL. Characterizing novel olfactory receptors expressed in the murine renal cortex. Am J Physiol Renal Physiol 2019; 317:F172-F186. [PMID: 31042061 DOI: 10.1152/ajprenal.00624.2018] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The kidney uses specialized G protein-coupled receptors, including olfactory receptors (ORs), to act as sensors of molecules and metabolites. In the present study, we cloned and studied seven renal ORs, which we previously found to be expressed in the murine renal cortex. As most ORs are orphan receptors, our goal was to identify ligands for these ORs in the hope that this will guide future research into their functional roles. We identified novel ligands for two ORs: Olfr558 and Olfr90. For Olfr558, we confirmed activation by previously reported ligands and identified 16 additional carboxylic acids that activated this OR. The strongest activation of Olfr558 was produced by butyric, cyclobutanecarboxylic, isovaleric, 2-methylvaleric, 3-methylvaleric, 4-methylvaleric, and valeric acids. The primary in vivo source of both butyric and isovaleric acids is gut microbial metabolism. We also identified 14 novel ligands that activated Olfr90, the strongest of which were 2-methyl-4-propyl-1,3-oxathiane, 1-octen-3-ol, 2-octanol, and 3-octanol. Interestingly, 8 of these 14 ligands are of fungal origin. We also investigated the tissue distribution of these receptors and found that they are each found in a subset of "nonsensory" tissues. Finally, we examined the putative human orthologs of Olfr558 and Olfr90 and found that the human ortholog of Olfr558 (OR51E1) has a similar ligand profile, indicating that the role of this OR is likely evolutionarily conserved. In summary, we examined seven novel renal ORs and identified new ligands for Olfr558 and Olfr90, which imply that both of these receptors serve to detect metabolites produced by microorganisms.
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Affiliation(s)
- Victoria L Halperin Kuhns
- Department of Physiology, Johns Hopkins University School of Medicine , Baltimore, Maryland.,Department of Physiology, University of Maryland School of Medicine , Baltimore, Maryland
| | - Jason Sanchez
- Department of Physiology, Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Dylan C Sarver
- Department of Physiology, Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Zoya Khalil
- Department of Physiology, Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Premraj Rajkumar
- Department of Physiology, Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Kieren A Marr
- Transplant and Oncology Infectious Diseases, Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Jennifer L Pluznick
- Department of Physiology, Johns Hopkins University School of Medicine , Baltimore, Maryland
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127
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Licon CC, Bosc G, Sabri M, Mantel M, Fournel A, Bushdid C, Golebiowski J, Robardet C, Plantevit M, Kaytoue M, Bensafi M. Chemical features mining provides new descriptive structure-odor relationships. PLoS Comput Biol 2019; 15:e1006945. [PMID: 31022180 PMCID: PMC6504111 DOI: 10.1371/journal.pcbi.1006945] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 05/07/2019] [Accepted: 03/11/2019] [Indexed: 12/30/2022] Open
Abstract
An important goal in researching the biology of olfaction is to link the perception of smells to the chemistry of odorants. In other words, why do some odorants smell like fruits and others like flowers? While the so-called stimulus-percept issue was resolved in the field of color vision some time ago, the relationship between the chemistry and psycho-biology of odors remains unclear up to the present day. Although a series of investigations have demonstrated that this relationship exists, the descriptive and explicative aspects of the proposed models that are currently in use require greater sophistication. One reason for this is that the algorithms of current models do not consistently consider the possibility that multiple chemical rules can describe a single quality despite the fact that this is the case in reality, whereby two very different molecules can evoke a similar odor. Moreover, the available datasets are often large and heterogeneous, thus rendering the generation of multiple rules without any use of a computational approach overly complex. We considered these two issues in the present paper. First, we built a new database containing 1689 odorants characterized by physicochemical properties and olfactory qualities. Second, we developed a computational method based on a subgroup discovery algorithm that discriminated perceptual qualities of smells on the basis of physicochemical properties. Third, we ran a series of experiments on 74 distinct olfactory qualities and showed that the generation and validation of rules linking chemistry to odor perception was possible. Taken together, our findings provide significant new insights into the relationship between stimulus and percept in olfaction. In addition, by automatically extracting new knowledge linking chemistry of odorants and psychology of smells, our results provide a new computational framework of analysis enabling scientists in the field to test original hypotheses using descriptive or predictive modeling. An important issue in olfaction sciences deals with the question of how a chemical information can be translated into percepts. This is known as the stimulus-percept problem. Here, we set out to better understand this issue by combining knowledge about the chemistry and cognition of smells with computational olfaction. We also assumed that not only one, but several physicochemical models may describe a given olfactory quality. To achieve this aim, a first challenge was to set up a database with ~1700 molecules characterized by chemical features and described by olfactory qualities (e.g. fruity, woody). A second challenge consisted in developing a computational model enabling the discrimination of olfactory qualities based on these chemical features. By meeting these 2 challenges, we provided for several olfactory qualities new chemical models describing why an odorant molecule smells fruity or woody (among others). For most qualities, multiple (rather than a single) chemical models were generated. These findings provide new elements of knowledge about the relationship between odorant chemistry and perception. They also make it possible to envisage concrete applications in the aroma and fragrance field where chemical characterization of smells is an important step in the design of new products.
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Affiliation(s)
- Carmen C. Licon
- Lyon Neuroscience Research Center, University Lyon, CNRS UMR5292, France
- Food Science and Nutrition Department, California State University, Fresno, California, United States of America
| | - Guillaume Bosc
- INSA Lyon, CNRS, LIRIS UMR5205, France
- Infologic, Bourg-lès-Valence, France
| | - Mohammed Sabri
- Lyon Neuroscience Research Center, University Lyon, CNRS UMR5292, France
- Ecole Nationale Polytechnique d’Oran—Maurice Audin, Département de Mathématiques et Informatique, Oran, Algérie
| | - Marylou Mantel
- Lyon Neuroscience Research Center, University Lyon, CNRS UMR5292, France
| | - Arnaud Fournel
- Lyon Neuroscience Research Center, University Lyon, CNRS UMR5292, France
| | - Caroline Bushdid
- Institute of Chemistry of Nice, UMR CNRS 7272, Université Côte d’Azur, Nice, France
| | - Jerome Golebiowski
- Institute of Chemistry of Nice, UMR CNRS 7272, Université Côte d’Azur, Nice, France
- Department of Brain & Cognitive Sciences, DGIST, Daegu, Republic of Korea
| | | | | | - Mehdi Kaytoue
- INSA Lyon, CNRS, LIRIS UMR5205, France
- Infologic, Bourg-lès-Valence, France
| | - Moustafa Bensafi
- Lyon Neuroscience Research Center, University Lyon, CNRS UMR5292, France
- * E-mail:
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128
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Yuan S, Dahoun T, Brugarolas M, Pick H, Filipek S, Vogel H. Computational modeling of the olfactory receptor Olfr73 suggests a molecular basis for low potency of olfactory receptor-activating compounds. Commun Biol 2019; 2:141. [PMID: 31044166 PMCID: PMC6478719 DOI: 10.1038/s42003-019-0384-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Accepted: 03/11/2019] [Indexed: 12/17/2022] Open
Abstract
The mammalian olfactory system uses hundreds of specialized G-protein-coupled olfactory receptors (ORs) to discriminate a nearly unlimited number of odorants. Cognate agonists of most ORs have not yet been identified and potential non-olfactory processes mediated by ORs are unknown. Here, we used molecular modeling, fingerprint interaction analysis and molecular dynamics simulations to show that the binding pocket of the prototypical olfactory receptor Olfr73 is smaller, but more flexible, than binding pockets of typical non-olfactory G-protein-coupled receptors. We extended our modeling to virtual screening of a library of 1.6 million compounds against Olfr73. Our screen predicted 25 Olfr73 agonists beyond traditional odorants, of which 17 compounds, some with therapeutic potential, were validated in cell-based assays. Our modeling suggests a molecular basis for reduced interaction contacts between an odorant and its OR and thus the typical low potency of OR-activating compounds. These results provide a proof-of-principle for identifying novel therapeutic OR agonists.
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Affiliation(s)
- Shuguang Yuan
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 China
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Laboratory of Biomodelling, Faculty of Chemistry & Biological and Chemical Research Centre, Uni-versity of Warsaw, 02-093 Warsaw, Poland
| | - Thamani Dahoun
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Marc Brugarolas
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Horst Pick
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Slawomir Filipek
- Laboratory of Biomodelling, Faculty of Chemistry & Biological and Chemical Research Centre, Uni-versity of Warsaw, 02-093 Warsaw, Poland
| | - Horst Vogel
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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129
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Zhang R, Pan Y, Ahmed L, Block E, Zhang Y, Batista VS, Zhuang H. A Multispecific Investigation of the Metal Effect in Mammalian Odorant Receptors for Sulfur-Containing Compounds. Chem Senses 2019; 43:357-366. [PMID: 29659735 DOI: 10.1093/chemse/bjy022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Metal-coordinating compounds are generally known to have strong smells, a phenomenon that can be attributed to the fact that odorant receptors for intense-smelling compounds, such as those containing sulfur, may be metalloproteins. We previously identified a mouse odorant receptor (OR), Olfr1509, that requires copper ions for sensitive detection of a series of metal-coordinating odorants, including (methylthio)methanethiol (MTMT), a strong-smelling component of male mouse urine that attracts female mice. By combining mutagenesis and quantum mechanics/molecular mechanics (QM/MM) modeling, we identified candidate binding sites in Olfr1509 that may bind to the copper-MTMT complex. However, whether there are other receptors utilizing metal ions for ligand-binding and other sites important for receptor activation is still unknown. In this study, we describe a second mouse OR for MTMT with a copper effect, namely Olfr1019. In an attempt to investigate the functional changes of metal-coordinating ORs in multiple species and to decipher additional sites involved in the metal effect, we cloned various mammalian orthologs of the 2 mouse MTMT receptors, and a third mouse MTMT receptor, Olfr15, that does not have a copper effect. We found that the function of all 3 MTMT receptors varies greatly among species and that the response to MTMT always co-occurred with the copper effect. Furthermore, using ancestral reconstruction and QM/MM modeling combined with receptor functional assay, we found that the amino acid residue R260 in Olfr1509 and the respective R261 site in Olfr1019 may be important for receptor activation.
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Affiliation(s)
- Ruina Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiaotong University School of Medicine, Huangpu District, Shanghai, P. R. China
| | - Yi Pan
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiaotong University School of Medicine, Huangpu District, Shanghai, P. R. China
| | - Lucky Ahmed
- Department of Chemistry, Yale University, New Haven, CT, USA
| | - Eric Block
- Department of Chemistry, University at Albany, State University of New York, NY, USA
| | - Yuetian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiaotong University School of Medicine, Huangpu District, Shanghai, P. R. China
| | | | - Hanyi Zhuang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiaotong University School of Medicine, Huangpu District, Shanghai, P. R. China
- Institute of Health Sciences, Shanghai Jiaotong University School of Medicine/Shanghai Institutes for Biological Sciences of Chinese Academy of Sciences, Xuhui District, Shanghai, P. R. China
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130
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de March CA, Fukutani Y, Vihani A, Kida H, Matsunami H. Real-time In Vitro Monitoring of Odorant Receptor Activation by an Odorant in the Vapor Phase. J Vis Exp 2019. [PMID: 31081824 DOI: 10.3791/59446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Olfactory perception begins with the interaction of odorants with odorant receptors (OR) expressed by olfactory sensory neurons (OSN). Odor recognition follows a combinatorial coding scheme, where one OR can be activated by a set of odorants and one odorant can activate a combination of ORs. Through such combinatorial coding, organisms can detect and discriminate between a myriad of volatile odor molecules. Thus, an odor at a given concentration can be described by an activation pattern of ORs, which is specific to each odor. In that sense, cracking the mechanisms that the brain uses to perceive odor requires the understanding odorant-OR interactions. This is why the olfaction community is committed to "de-orphanize" these receptors. Conventional in vitro systems used to identify odorant-OR interactions have utilized incubating cell media with odorant, which is distinct from the natural detection of odors via vapor odorants dissolution into nasal mucosa before interacting with ORs. Here, we describe a new method that allows for real-time monitoring of OR activation via vapor-phase odorants. Our method relies on measuring cAMP release by luminescence using the Glosensor assay. It bridges current gaps between in vivo and in vitro approaches and provides a basis for a biomimetic volatile chemical sensor.
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Affiliation(s)
- Claire A de March
- Department of Molecular Genetics and Microbiology, Duke University Medical Center;
| | - Yosuke Fukutani
- Department of Molecular Genetics and Microbiology, Duke University Medical Center; Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology
| | - Aashutosh Vihani
- Department of Molecular Genetics and Microbiology, Duke University Medical Center; Department of Neurobiology, Duke University Medical Center
| | - Hitoshi Kida
- Department of Molecular Genetics and Microbiology, Duke University Medical Center; Department of Mechanical Systems, Engineering, Tokyo University of Agriculture and Technology
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center; Department of Neurobiology, Duke University Medical Center; Institute of Global Innovation Research, Tokyo University of Agriculture and Technology; Duke Institute for Brain Sciences, Duke University;
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131
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Competitive binding predicts nonlinear responses of olfactory receptors to complex mixtures. Proc Natl Acad Sci U S A 2019; 116:9598-9603. [PMID: 31000595 PMCID: PMC6511041 DOI: 10.1073/pnas.1813230116] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In color vision, the quantitative rules for mixing lights to make a target color are well understood. By contrast, the rules for mixing odorants to make a target odor remain elusive. A solution to this problem in vision relied on characterizing receptor responses to different wavelengths of light and subsequently relating these responses to perception. In olfaction, experimentally measuring receptor responses to a representative set of complex mixtures is intractable due to the vast number of possibilities. To meet this challenge, we develop a biophysical model that predicts mammalian receptor responses to complex mixtures using responses to single odorants. The dominant nonlinearity in our model is competitive binding (CB): Only one odorant molecule can attach to a receptor binding site at a time. This simple framework predicts receptor responses to mixtures of up to 12 monomolecular odorants to within 15% of experimental observations and provides a powerful method for leveraging limited experimental data. Simple extensions of our model describe phenomena such as synergy, overshadowing, and inhibition. We demonstrate that the presence of such interactions can be identified via systematic deviations from the competitive-binding model.
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132
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Jones EM, Jajoo R, Cancilla D, Lubock NB, Wang J, Satyadi M, Chong R, de March C, Bloom JS, Matsunami H, Kosuri S. A Scalable, Multiplexed Assay for Decoding GPCR-Ligand Interactions with RNA Sequencing. Cell Syst 2019; 8:254-260.e6. [PMID: 30904378 PMCID: PMC6907015 DOI: 10.1016/j.cels.2019.02.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 01/16/2019] [Accepted: 02/26/2019] [Indexed: 12/13/2022]
Abstract
G protein-coupled receptors (GPCRs) are central to how mammalian cells sense and respond to chemicals. Mammalian olfactory receptors (ORs), the largest family of GPCRs, mediate the sense of smell through activation by small molecules, though for most bonafide ligands, they have not been identified. Here, we introduce a platform to screen large chemical panels against multiplexed GPCR libraries using next-generation sequencing of barcoded genetic reporters in stably engineered human cell lines. We mapped 39 mammalian ORs against 181 odorants and identified 79 interactions that have not been reported to our knowledge, including ligands for 15 previously orphaned receptors. This multiplexed receptor assay allows the cost-effective mapping of large chemical libraries to receptor repertoires at scale.
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Affiliation(s)
- Eric M Jones
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Rishi Jajoo
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Daniel Cancilla
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Nathan B Lubock
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Jeffrey Wang
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Megan Satyadi
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Rockie Chong
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA
| | - Claire de March
- Department of Molecular Genetics and Microbiology, and Department of Neurobiology, and Duke Institute for Brain Sciences, Duke University Medical Center, Research Drive, Durham, NC 27710, USA
| | - Joshua S Bloom
- Department of Human Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, and Department of Neurobiology, and Duke Institute for Brain Sciences, Duke University Medical Center, Research Drive, Durham, NC 27710, USA
| | - Sriram Kosuri
- Department of Chemistry and Biochemistry, UCLA-, DOE Institute for Genomics and Proteomics, Molecular Biology Institute, Quantitative and Computational Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA.
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133
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Abstract
Unraveling the sense of smell relies on understanding how odorant receptors recognize odorant molecules. Given the vastness of the odorant chemical space and the complexity of the odorant receptor space, computational methods are in line to propose rules connecting them. We hereby propose an in silico and an in vitro approach, which, when combined are extremely useful for assessing chemogenomic links. In this chapter we mostly focus on the mining of already existing data through machine learning methods. This approach allows establishing predictions that map the chemical space and the receptor space. Then, we describe the method for assessing the activation of odorant receptors and their mutants through luciferase reporter gene functional assays.
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134
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Bushdid C, de March CA, Topin J, Do M, Matsunami H, Golebiowski J. Mammalian class I odorant receptors exhibit a conserved vestibular-binding pocket. Cell Mol Life Sci 2019; 76:995-1004. [PMID: 30599066 PMCID: PMC7313674 DOI: 10.1007/s00018-018-2996-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 12/22/2022]
Abstract
Odorant receptors represent the largest family of mammalian G protein-coupled receptors. Phylogenetically, they are split into two classes (I and II). By analyzing the entire subclass I odorant receptors sequences, we identified two class I-specific and highly conserved motifs. These are predicted to face each other at the extra-cellular portion of the transmembrane domain, forming a vestibular site at the entrance to the orthosteric-binding cavity. Molecular dynamics simulation combined with site-directed mutagenesis and in vitro functional assays confirm the functional role of this vestibular site in ligand-driven activation. Mutations at this part of the receptor differentially affect the receptor response to four agonists. Since this vestibular site is involved in ligand recognition, it could serve ligand design that targets specifically this sub-genome of mammalian odorant receptors.
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Affiliation(s)
- Caroline Bushdid
- Institute of Chemistry - Nice, UMR CNRS 7272, Université Côte d'Azur, Nice, France
| | - Claire A de March
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Jérémie Topin
- Institute of Chemistry - Nice, UMR CNRS 7272, Université Côte d'Azur, Nice, France
| | - Matthew Do
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.
- Department of Neurobiology, Duke Institute for Brain Sciences, Duke University, Durham, NC, 27710, USA.
| | - Jérôme Golebiowski
- Institute of Chemistry - Nice, UMR CNRS 7272, Université Côte d'Azur, Nice, France.
- Department of Brain and Cognitive Sciences, DGIST, Daegu, Republic of Korea.
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135
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Feng G, Zhou W. Nostril-specific and structure-based olfactory learning of chiral discrimination in human adults. eLife 2019; 8:41296. [PMID: 30652684 PMCID: PMC6336403 DOI: 10.7554/elife.41296] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 12/23/2018] [Indexed: 12/23/2022] Open
Abstract
Practice makes perfect. In human olfaction, such plasticity is generally assumed to occur at the level of cortical synthetic processing that shares information from both nostrils. Here we present findings that challenge this view. In two experiments, we trained human adults unirhinally for the discrimination between odor enantiomers over a course of about 10 to 11 days. Results showed that training-induced perceptual gain was restricted to the trained nostril yet partially generalized to untrained odor enantiomers in a structure- rather than quality- based manner. In other words, learning enhanced the differentiation of chirality (molecular configuration) as opposed to overall odor quality (odor object) per se. These findings argue that, unlike earlier beliefs, one nostril does not readily know what the other learns. Moreover, the initial analytical processing of the structural features of uninarial olfactory input remains plastic in human adults. Although we may only become consciously aware of our sense of smell when we encounter something pungent, it can greatly influence our quality of life. Smells are processed by our olfactory system, a collection of receptors and nerve cells in the nose and brain. Odor molecules activate the olfactory system when they bind to receptors in the nostrils. These molecules can have a wide range of chemical and physical properties. However, some odor molecules are mirror images of each other. These variants are known as enantiomers. Some people can naturally smell the difference between enantiomers; others can be taught how to tell them apart. Studying this training process could help us to understand how the olfactory system adapts to new circumstances. Feng and Zhou trained volunteers to distinguish between odor enantiomers – but only using one nostril. After training, the volunteers were better able to tell the difference between different enantiomers – even for certain scents they had not been trained to discriminate – when sniffing through the trained nostril. However, they got no better at distinguishing between enantiomers when they sniffed them using the other nostril. Overall, the results reported by Feng and Zhou confirm that human adults can learn how to process the structural features of odorants. However, in contrast to earlier beliefs, they also suggest that one nostril does not readily know what the other learns. This new understanding of how the olfactory system adapts could ultimately help us to develop therapies to restore a lost sense of smell.
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Affiliation(s)
- Guo Feng
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.,Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.,Psychological Research and Counseling Center, Southwest Jiaotong University, Chengdu, China
| | - Wen Zhou
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.,Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
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136
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Bird DJ, Murphy WJ, Fox-Rosales L, Hamid I, Eagle RA, Van Valkenburgh B. Olfaction written in bone: cribriform plate size parallels olfactory receptor gene repertoires in Mammalia. Proc Biol Sci 2019. [PMID: 29540522 DOI: 10.1098/rspb.2018.0100] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The evolution of mammalian olfaction is manifested in a remarkable diversity of gene repertoires, neuroanatomy and skull morphology across living species. Olfactory receptor genes (ORGs), which initiate the conversion of odorant molecules into odour perceptions and help an animal resolve the olfactory world, range in number from a mere handful to several thousand genes across species. Within the snout, each of these ORGs is exclusively expressed by a discrete population of olfactory sensory neurons (OSNs), suggesting that newly evolved ORGs may be coupled with new OSN populations in the nasal epithelium. Because OSN axon bundles leave high-fidelity perforations (foramina) in the bone as they traverse the cribriform plate (CP) to reach the brain, we predicted that taxa with larger ORG repertoires would have proportionately expanded footprints in the CP foramina. Previous work found a correlation between ORG number and absolute CP size that disappeared after accounting for body size. Using updated, digital measurement data from high-resolution CT scans and re-examining the relationship between CP and body size, we report a striking linear correlation between relative CP area and number of functional ORGs across species from all mammalian superorders. This correlation suggests strong developmental links in the olfactory pathway between genes, neurons and skull morphology. Furthermore, because ORG number is linked to olfactory discriminatory function, this correlation supports relative CP size as a viable metric for inferring olfactory capacity across modern and extinct species. By quantifying CP area from a fossil sabertooth cat (Smilodon fatalis), we predicted a likely ORG repertoire for this extinct felid.
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Affiliation(s)
- Deborah J Bird
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 610 Charles E. Young Drive South, Los Angeles, CA 90095-8347, USA
| | - William J Murphy
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA
| | - Lester Fox-Rosales
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 610 Charles E. Young Drive South, Los Angeles, CA 90095-8347, USA
| | - Iman Hamid
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 610 Charles E. Young Drive South, Los Angeles, CA 90095-8347, USA
| | - Robert A Eagle
- Department of Atmospheric and Oceanic Sciences, Institute of the Environment and Sustainability, University of California Los Angeles, 520 Portola Plaza, Math Sciences Building 7127, Los Angeles, CA 90095, USA
| | - Blaire Van Valkenburgh
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 610 Charles E. Young Drive South, Los Angeles, CA 90095-8347, USA
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137
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Wu C, Thach TT, Kim YJ, Lee SJ. Olfactory receptor 43 reduces hepatic lipid accumulation and adiposity in mice. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:489-499. [PMID: 30639733 DOI: 10.1016/j.bbalip.2019.01.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 12/30/2018] [Accepted: 01/05/2019] [Indexed: 12/14/2022]
Abstract
Olfactory receptors are primarily expressed in nasal olfactory epithelium, but these receptors are also ectopically expressed in diverse tissues. In this study, we investigated the biological functions of Olfr43, a mouse homolog of human OR1A1, in cultured hepatocytes and mice to assess its functionality in lipid metabolism. Olfr43 was expressed in mouse hepatocytes, and Olfr43 activation by a known ligand, (-)-carvone, stimulated cAMP response element-binding protein (CREB) activity. In ligand-receptor binding studies using site-directed mutagenesis, (-)-carvone binding required two residues, M257 and Y258, in Olfr43. In the mouse study, oral administration of (-)-carvone for 5 weeks in high-fat diet-fed mice improved energy metabolism, including reductions in hepatic steatosis and adiposity, and improved glucose and insulin tolerance. In mouse livers and cultured mouse hepatocytes, Olfr43 activation simulated the CREB-hairy and enhancer of split 1 (HES1)-peroxisome proliferator-activated receptor (PPAR)-γ signaling axis, leading to a reduction in hepatic triglyceride accumulation in the mouse liver. Thus, long-term administration of (-)-carvone reduces hepatic steatosis. The knockdown of Olfr43 gene expression in cultured hepatocytes negated these effects of (-)-carvone. In conclusion, an ectopic olfactory receptor, hepatic Olfr43, regulates energy metabolism via the CREB-HES1-PPARγ signaling axis.
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Affiliation(s)
- Chunyan Wu
- Department of Biotechnology, School of Life Sciences and Biotechnology for BK21 PLUS, Korea University, Seoul 02841, Republic of Korea
| | - Trung Thanh Thach
- Department of Biotechnology, School of Life Sciences and Biotechnology for BK21 PLUS, Korea University, Seoul 02841, Republic of Korea
| | - Yeon-Ji Kim
- Department of Biotechnology, School of Life Sciences and Biotechnology for BK21 PLUS, Korea University, Seoul 02841, Republic of Korea
| | - Sung-Joon Lee
- Department of Biotechnology, School of Life Sciences and Biotechnology for BK21 PLUS, Korea University, Seoul 02841, Republic of Korea.
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138
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Abstract
Olfaction plays a critical role in several aspects of life. Olfactory disorders are very common in the general population, and can lead to malnutrition, weight loss, food poisoning, depression, and other disturbances. Odorants are first detected in the upper region of the nose by the main olfactory epithelium (OE). In this region, millions of olfactory sensory neurons (OSNs) interact with odor molecules through the odorant receptors (ORs), which belong to the superfamily of G protein-coupled receptors. The binding of odors to the ORs initiates an electrical signal that travels along the axons to the main olfactory bulb of the brain. The information is then transmitted to other regions of the brain, leading to odorant perception and emotional and behavioral responses. In the OE, OSNs die and are continuously replaced from stem cells localized in the epithelium's basal region. Damage to this epithelium can be caused by multiple factors, leading to anosmia (smell loss). In this chapter, we introduce the basic organization of the OE and focus on the molecular mechanisms involved in odorant perception. We also describe recent experiments that address the mechanisms of OSNs regeneration in response to neuronal injury.
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Affiliation(s)
- Isaías Glezer
- Department of Biochemistry, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Bettina Malnic
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo, São Paulo, Brazil.
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139
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Teşileanu T, Cocco S, Monasson R, Balasubramanian V. Adaptation of olfactory receptor abundances for efficient coding. eLife 2019; 8:39279. [PMID: 30806351 PMCID: PMC6398974 DOI: 10.7554/elife.39279] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 02/13/2019] [Indexed: 01/27/2023] Open
Abstract
Olfactory receptor usage is highly heterogeneous, with some receptor types being orders of magnitude more abundant than others. We propose an explanation for this striking fact: the receptor distribution is tuned to maximally represent information about the olfactory environment in a regime of efficient coding that is sensitive to the global context of correlated sensor responses. This model predicts that in mammals, where olfactory sensory neurons are replaced regularly, receptor abundances should continuously adapt to odor statistics. Experimentally, increased exposure to odorants leads variously, but reproducibly, to increased, decreased, or unchanged abundances of different activated receptors. We demonstrate that this diversity of effects is required for efficient coding when sensors are broadly correlated, and provide an algorithm for predicting which olfactory receptors should increase or decrease in abundance following specific environmental changes. Finally, we give simple dynamical rules for neural birth and death processes that might underlie this adaptation.
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Affiliation(s)
- Tiberiu Teşileanu
- Center for Computational BiologyFlatiron InstituteNew YorkUnited States,Initiative for the Theoretical Sciences, The Graduate CenterCity University of New YorkNew YorkUnited States,David Rittenhouse LaboratoriesUniversity of PennsylvaniaPhiladelphiaUnited States
| | - Simona Cocco
- Laboratoire de Physique StatistiqueÉcole Normale Supérieure and CNRS UMR 8550, PSL Research, UPMC Sorbonne UniversitéParisFrance
| | - Rémi Monasson
- Laboratoire de Physique ThéoriqueÉcole Normale Supérieure and CNRS UMR 8550, PSL Research, UPMC Sorbonne UniversitéParisFrance
| | - Vijay Balasubramanian
- Initiative for the Theoretical Sciences, The Graduate CenterCity University of New YorkNew YorkUnited States,David Rittenhouse LaboratoriesUniversity of PennsylvaniaPhiladelphiaUnited States
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140
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Maßberg D, Hatt H. Human Olfactory Receptors: Novel Cellular Functions Outside of the Nose. Physiol Rev 2018; 98:1739-1763. [PMID: 29897292 DOI: 10.1152/physrev.00013.2017] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Olfactory receptors (ORs) are not exclusively expressed in the olfactory sensory neurons; they are also observed outside of the olfactory system in all other human tissues tested to date, including the testis, lung, intestine, skin, heart, and blood. Within these tissues, certain ORs have been determined to be exclusively expressed in only one tissue, whereas other ORs are more widely distributed in many different tissues throughout the human body. For most of the ectopically expressed ORs, limited data are available for their functional roles. They have been shown to be involved in the modulation of cell-cell recognition, migration, proliferation, the apoptotic cycle, exocytosis, and pathfinding processes. Additionally, there is a growing body of evidence that they have the potential to serve as diagnostic and therapeutic tools, as ORs are highly expressed in different cancer tissues. Interestingly, in addition to the canonical signaling pathways activated by ORs in olfactory sensory neurons, alternative pathways have been demonstrated in nonolfactory tissues. In this review, the existing data concerning the expression, as well as the physiological and pathophysiological functions, of ORs outside of the nose are highlighted to provide insights into future lines of research.
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Affiliation(s)
- Désirée Maßberg
- Ruhr-University Bochum, Department of Cell Physiology , Bochum , Germany
| | - Hanns Hatt
- Ruhr-University Bochum, Department of Cell Physiology , Bochum , Germany
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141
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Regulation of Adipogenesis and Thermogenesis through Mouse Olfactory Receptor 23 Stimulated by α-Cedrene in 3T3-L1 Cells. Nutrients 2018; 10:nu10111781. [PMID: 30453511 PMCID: PMC6265911 DOI: 10.3390/nu10111781] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 11/11/2018] [Accepted: 11/14/2018] [Indexed: 12/19/2022] Open
Abstract
Olfactory receptors (ORs) are G protein-coupled receptors that perform important physiological functions beyond their role as odorant detectors in the olfactory sensory neurons. In the present study, we describe a novel role for one of these ORs, mouse olfactory receptor 23 (MOR23), as a regulator of adipogenesis and thermogenesis in 3T3-L1 cells. Downregulation of MOR23 by small interfering RNA in 3T3-L1 cells enhanced intracellular lipid accumulation and reduced the oxygen consumption rate. In agreement with this phenotype, MOR23 deletion significantly decreased intracellular cyclic adenosine monophosphate (cAMP) levels and protein amounts of adenylyl cyclase 3 (ADCY3), protein kinase A catalytic subunit (PKA Cα), phospho-5′-adenosine monophosphate (AMP)-activated protein kinase (AMPK), and phospho-cAMP-responsive element-binding protein (CREB), along with upregulation of adipogenic genes and downregulation of genes involved in thermogenesis. Activation of MOR23 by α-cedrene, a novel natural ligand of MOR23, significantly reduced lipid content, increased the oxygen consumption rate, and stimulated reprogramming of the metabolic signature of 3T3-L1 cells, and these changes elicited by α-cedrene were absent in MOR23-deficient cells. These findings point to the role of MOR23 as a regulator of adipogenesis and thermogenesis in adipocytes.
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142
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Kida H, Fukutani Y, Mainland JD, de March CA, Vihani A, Li YR, Chi Q, Toyama A, Liu L, Kameda M, Yohda M, Matsunami H. Vapor detection and discrimination with a panel of odorant receptors. Nat Commun 2018; 9:4556. [PMID: 30385742 PMCID: PMC6212438 DOI: 10.1038/s41467-018-06806-w] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 09/04/2018] [Indexed: 12/29/2022] Open
Abstract
Olfactory systems have evolved the extraordinary capability to detect and discriminate volatile odorous molecules (odorants) in the environment. Fundamentally, this process relies on the interaction of odorants and their cognate olfactory receptors (ORs) encoded in the genome. Here, we conducted a cell-based screen using over 800 mouse ORs against seven odorants, resulting in the identification of a set of high-affinity and/or broadly-tuned ORs. We then test whether heterologously expressed ORs respond to odors presented in vapor phase by individually expressing 31 ORs to measure cAMP responses against vapor phase odor stimulation. Comparison of response profiles demonstrates this platform is capable of discriminating between structural analogs. Lastly, co-expression of carboxyl esterase Ces1d expressed in olfactory mucosa resulted in marked changes in activation of specific odorant-OR combinations. Altogether, these results establish a cell-based volatile odor detection and discrimination platform and form the basis for an OR-based volatile odor sensor. Biomimetic “noses” have been proposed to replace trained animals for chemical detection. Here the authors select 31 mouse olfactory receptors (ORs), based on a large cell-based screen of >800 ORs against seven chemicals, to build an OR-based sensor able to discriminate structurally similar compounds.
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Affiliation(s)
- Hitoshi Kida
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.,Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan
| | - Yosuke Fukutani
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.,Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan
| | - Joel D Mainland
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.,Monell Chemical Senses Center, Philadelphia, PA, 19104, USA.,Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Claire A de March
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Aashutosh Vihani
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.,Department of Neurobiology, Neurobiology graduate program, Duke University Medical Center, Durham, NC, 27710, USA
| | - Yun Rose Li
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.,Department of Radiation Oncology, Helen Diller Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Qiuyi Chi
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Akemi Toyama
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Linda Liu
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Masaharu Kameda
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan.,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan
| | - Masafumi Yohda
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan.,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA. .,Department of Neurobiology, Neurobiology graduate program, Duke University Medical Center, Durham, NC, 27710, USA. .,Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan. .,Duke Institute for Brain Sciences, Duke University, Durham, NC, 27710, USA.
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143
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Kwon OS, Song HS, Park TH, Jang J. Conducting Nanomaterial Sensor Using Natural Receptors. Chem Rev 2018; 119:36-93. [DOI: 10.1021/acs.chemrev.8b00159] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oh Seok Kwon
- Bionanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Republic of Korea
- Nanobiotechnology and Bioinformatics (Major), University of Science & Technology (UST), Daejon 34141, Republic of Korea
| | - Hyun Seok Song
- Sensor System Research Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Division of Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Cheongju 28119, Republic of Korea
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Tai Hyun Park
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Jyongsik Jang
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
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144
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Han YE, Kang CW, Oh JH, Park SH, Ku CR, Cho YH, Lee MK, Lee EJ. Olfactory Receptor OR51E1 Mediates GLP-1 Secretion in Human and Rodent Enteroendocrine L Cells. J Endocr Soc 2018; 2:1251-1258. [PMID: 30402589 PMCID: PMC6215084 DOI: 10.1210/js.2018-00165] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 10/08/2018] [Indexed: 01/01/2023] Open
Abstract
Glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), produced by intestinal enteroendocrine L cells, are important gut hormones that coordinate gastrointestinal physiology, metabolism, and appetite. We aimed to investigate the role of olfactory receptor (OR) OR51E1 in GLP-1 and PYY secretion. We analyzed the expression of olfactory marker protein (OMP), an indicator of OR-mediated events in nonolfactory systems, in human intestinal L cells. Furthermore, we analyzed OMP and OR51E1 expression in the L cell line NCI-H716. To investigate whether odorant-activated OR signaling stimulates GLP-1 and PYY secretion, we used nonanoic acid, a known OR51E1 ligand. Treatment with 100 μM nonanoic acid increased GLP-1 secretion by 2.32 ± 0.41-fold and PYY secretion by 1.44 ± 0.10-fold; however, this effect was attenuated on small interfering RNA-mediated OR51E1 knockdown. Oral administration of nonanoic acid to rats resulted in a 2.89 ± 0.53-fold increase in GLP-1 levels and reductions in blood glucose levels compared with the control group. Nonanoic acid stimulates GLP-1 and PYY secretion via OR51E1 signaling in L cells, thereby indicating a potential role of OR-mediated events in GLP-1 and PYY secretion; this could be translated into a therapeutic approach in treating diabetes.
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Affiliation(s)
- Ye Eon Han
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Republic of Korea.,Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Chan Woo Kang
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Republic of Korea.,Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Joo Heon Oh
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Republic of Korea.,Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Se Hee Park
- Department of Endocrinology, National Health Insurance Service Ilsan Hospital, Gyeonggi-do, Republic of Korea
| | - Cheol Ryong Ku
- Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Yoon Hee Cho
- Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Mi Kyung Lee
- Department of Pathology, National Health Insurance Service Ilsan Hospital, Gyeonggi-do, Republic of Korea
| | - Eun Jig Lee
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Republic of Korea.,Endocrinology, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
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145
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Sparsened neuronal activity in an optogenetically activated olfactory glomerulus. Sci Rep 2018; 8:14955. [PMID: 30297851 PMCID: PMC6175855 DOI: 10.1038/s41598-018-33021-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 09/07/2018] [Indexed: 12/04/2022] Open
Abstract
Glomeruli are the functional units of olfactory information processing but little remains known about their individual unit function. This is due to their widespread activation by odor stimuli. We expressed channelrhodopsin-2 in a single olfactory sensory neuron type, and used laser stimulation and simultaneous in vivo calcium imaging to study the responses of a single glomerulus to optogenetic stimulation. Calcium signals in the neuropil of this glomerulus were representative of the sensory input and nearly identical if evoked by intensity-matched odor and laser stimuli. However, significantly fewer glomerular layer interneurons and olfactory bulb output neurons (mitral cells) responded to optogenetic versus odor stimuli, resulting in a small and spatially compact optogenetic glomerular unit response. Temporal features of laser stimuli were represented with high fidelity in the neuropil of the glomerulus and the mitral cells, but not in interneurons. Increases in laser stimulus intensity were encoded by larger signal amplitudes in all compartments of the glomerulus, and by the recruitment of additional interneurons and mitral cells. No spatial expansion of the glomerular unit response was observed in response to stronger input stimuli. Our data are among the first descriptions of input-output transformations in a selectively activated olfactory glomerulus.
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146
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Leitch O, Lennard C, Paul Kirkbride K, Anderson A. Drosophila melanogaster odorant receptors as volatile compound detectors in forensic science: a proof-of-concept study. Anal Bioanal Chem 2018; 410:7739-7747. [PMID: 30280229 DOI: 10.1007/s00216-018-1390-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 09/05/2018] [Accepted: 09/19/2018] [Indexed: 01/05/2023]
Abstract
The ability to detect and identify substances based on the volatile compounds (odors) they emit is relied upon heavily for numerous investigative purposes. Animals have an innate olfactory sensitivity and selectivity that out-performs current instrumentation. This has led to immense interest in their employment as chemical sensors for a range of applications, including forensic science, both as whole organisms and as sensing elements in biosensors. Using electrophysiological and calcium imaging assays, this research examined the response of Drosophila melanogaster olfactory receptors (ORs) to odor compounds significant in forensic science and assessed their potential utility as volatile compound sensors. This investigation illustrated the different sensitivities, selectivities, and sensing features of individual ORs and demonstrated that their employment for detection purposes is feasible. While further research expanding on this study will be required to demonstrate the performance characteristics that an OR-based detection system will ultimately possess, this research provides an encouraging first step towards the goal of utilizing isolated biological ORs as volatile compound sensors in forensic science.
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Affiliation(s)
- Olivia Leitch
- National Centre for Forensic Studies, University of Canberra, Canberra, ACT, 2601, Australia. .,CSIRO Health and Biosecurity, Canberra, ACT, 2601, Australia. .,School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
| | - Chris Lennard
- National Centre for Forensic Studies, University of Canberra, Canberra, ACT, 2601, Australia.,School of Science and Health, Western Sydney University, Penrith, NSW, 2751, Australia
| | - K Paul Kirkbride
- The College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Alisha Anderson
- CSIRO Health and Biosecurity, Canberra, ACT, 2601, Australia
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147
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Expression of the Cerebral Olfactory Receptors Olfr110/111 and Olfr544 Is Altered During Aging and in Alzheimer’s Disease-Like Mice. Mol Neurobiol 2018; 56:2057-2072. [DOI: 10.1007/s12035-018-1196-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 06/26/2018] [Indexed: 01/06/2023]
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148
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Abaffy T, Bain JR, Muehlbauer MJ, Spasojevic I, Lodha S, Bruguera E, O'Neal SK, Kim SY, Matsunami H. A Testosterone Metabolite 19-Hydroxyandrostenedione Induces Neuroendocrine Trans-Differentiation of Prostate Cancer Cells via an Ectopic Olfactory Receptor. Front Oncol 2018; 8:162. [PMID: 29892571 PMCID: PMC5985834 DOI: 10.3389/fonc.2018.00162] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 04/30/2018] [Indexed: 12/22/2022] Open
Abstract
Olfactory receptor OR51E2, also known as a Prostate Specific G-Protein Receptor, is highly expressed in prostate cancer but its function is not well understood. Through in silico and in vitro analyses, we identified 24 agonists and 1 antagonist for this receptor. We detected that agonist 19-hydroxyandrostenedione, a product of the aromatase reaction, is endogenously produced upon receptor activation. We characterized the effects of receptor activation on metabolism using a prostate cancer cell line and demonstrated decreased intracellular anabolic signals and cell viability, induction of cell cycle arrest, and increased expression of neuronal markers. Furthermore, upregulation of neuron-specific enolase by agonist treatment was abolished in OR51E2-KO cells. The results of our study suggest that OR51E2 activation results in neuroendocrine trans-differentiation. These findings reveal a new role for OR51E2 and establish this G-protein coupled receptor as a novel therapeutic target in the treatment of prostate cancer.
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Affiliation(s)
- Tatjana Abaffy
- Department of Molecular Genetics and Microbiology, Duke Cancer Institute, Duke University School of Medicine, Durham, NC, United States
| | - James R Bain
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, United States
| | - Michael J Muehlbauer
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, United States
| | - Ivan Spasojevic
- Department of Medicine, Duke University School of Medicine, Durham, NC, United States
| | - Shweta Lodha
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, United States
| | - Elisa Bruguera
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, United States
| | - Sara K O'Neal
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, United States
| | - So Young Kim
- Department of Molecular Genetics and Microbiology, Functional Genomics Shared Resource, Duke University School of Medicine, Durham, NC, United States
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Department of Neurobiology, Duke Institute for Brain Sciences, Duke Cancer Institute, Duke University School of Medicine, Durham, NC, United States
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149
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Zhou YH, Zhang ZW, Fu YF, Zhang GC, Yuan S. Carbon Dioxide, Odorants, Heat and Visible Cues Affect Wild Mosquito Landing in Open Spaces. Front Behav Neurosci 2018; 12:86. [PMID: 29867387 PMCID: PMC5949359 DOI: 10.3389/fnbeh.2018.00086] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/19/2018] [Indexed: 12/25/2022] Open
Abstract
CO2 and other chemicals affect mosquito blood meal seeking behavior. Heat, humidity and black color can also serve as orientation cues. However mosquito attraction does not necessarily mean that it will land. The sequence of the cues used for mosquito landing is unclear. We performed a field study with wild mosquitoes in an open space and found that no chemicals (except pyrethrins) could completely prevent mosquitoes from landing. CO2 mimics cyclopentanone and pyridine attracted mosquitoes but did not lead to landing. No mosquito was caught in the absence of heat, although in the presence of CO2. Mosquito females commonly explore visible black objects by eyes, which is independent of infrared radiation. Humidification around the heat source may increase the detection distance but it did not affect mosquito landing. If a black object was located distant from the CO2 and heat, mosquitoes still explored the heat source. Relative to CO2 and heat, odorants, humidity and black color show lesser effects on mosquito landing.
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Affiliation(s)
- Yang-Hong Zhou
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Zhong-Wei Zhang
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yu-Fan Fu
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Gong-Chang Zhang
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Shu Yuan
- College of Resources, Sichuan Agricultural University, Chengdu, China
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150
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Bushdid C, de March CA, Fiorucci S, Matsunami H, Golebiowski J. Agonists of G-Protein-Coupled Odorant Receptors Are Predicted from Chemical Features. J Phys Chem Lett 2018; 9:2235-2240. [PMID: 29648835 PMCID: PMC7294703 DOI: 10.1021/acs.jpclett.8b00633] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Predicting the activity of chemicals for a given odorant receptor is a longstanding challenge. Here the activity of 258 chemicals on the human G-protein-coupled odorant receptor (OR)51E1, also known as prostate-specific G-protein-coupled receptor 2 (PSGR2), was virtually screened by machine learning using 4884 chemical descriptors as input. A systematic control by functional in vitro assays revealed that a support vector machine algorithm accurately predicted the activity of a screened library. It allowed us to identify two novel agonists in vitro for OR51E1. The transferability of the protocol was assessed on OR1A1, OR2W1, and MOR256-3 odorant receptors, and, in each case, novel agonists were identified with a hit rate of 39-50%. We further show how ligands' efficacy is encoded into residues within OR51E1 cavity using a molecular modeling protocol. Our approach allows widening the chemical spaces associated with odorant receptors. This machine-learning protocol based on chemical features thus represents an efficient tool for screening ligands for G-protein-coupled odorant receptors that modulate non-olfactory functions or, upon combinatorial activation, give rise to our sense of smell.
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Affiliation(s)
- C. Bushdid
- Institute of Chemistry of Nice, UMR CNRS 7272, Université Côte d’Azur, Nice, France
| | - C. A. de March
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - S. Fiorucci
- Institute of Chemistry of Nice, UMR CNRS 7272, Université Côte d’Azur, Nice, France
| | - H. Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710, United States
- Department of Neurobiology and Duke Institute for Brain Sciences, Duke University, Durham, North Carolina 27710, United States
- Corresponding Authors: (J.G.)., (H.M.)
| | - J. Golebiowski
- Institute of Chemistry of Nice, UMR CNRS 7272, Université Côte d’Azur, Nice, France
- Department of Brain & Cognitive Sciences, DGIST, Daegu, Republic of Korea
- Corresponding Authors: (J.G.)., (H.M.)
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