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Jiang HC, Park SJ, Wang IH, Bear DM, Nowlan A, Greer PL. CD20/MS4A1 is a mammalian olfactory receptor expressed in a subset of olfactory sensory neurons that mediates innate avoidance of predators. Nat Commun 2024; 15:3360. [PMID: 38637611 PMCID: PMC11026480 DOI: 10.1038/s41467-024-47698-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 04/05/2024] [Indexed: 04/20/2024] Open
Abstract
The mammalian olfactory system detects and discriminates between millions of odorants to elicit appropriate behavioral responses. While much has been learned about how olfactory sensory neurons detect odorants and signal their presence, how specific innate, unlearned behaviors are initiated in response to ethologically relevant odors remains poorly understood. Here, we show that the 4-transmembrane protein CD20, also known as MS4A1, is expressed in a previously uncharacterized subpopulation of olfactory sensory neurons in the main olfactory epithelium of the murine nasal cavity and functions as a mammalian olfactory receptor that recognizes compounds produced by mouse predators. While wildtype mice avoid these predator odorants, mice genetically deleted of CD20 do not appropriately respond. Together, this work reveals a CD20-mediated odor-sensing mechanism in the mammalian olfactory system that triggers innate behaviors critical for organismal survival.
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Affiliation(s)
- Hao-Ching Jiang
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Sung Jin Park
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - I-Hao Wang
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Interdisciplinary Graduate Program, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Daniel M Bear
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Wu Tsai Neurosciences Institute, Stanford University, Palo Alto, CA, USA
| | - Alexandra Nowlan
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Paul L Greer
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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Jiang HC, Park SJ, Wang IH, Bear DM, Nowlan A, Greer PL. CD20 is a mammalian odorant receptor expressed in a subset of olfactory sensory neurons that mediates innate avoidance of predators. RESEARCH SQUARE 2023:rs.3.rs-3290152. [PMID: 37790559 PMCID: PMC10543371 DOI: 10.21203/rs.3.rs-3290152/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The mammalian olfactory system detects and discriminates between millions of odorants to elicit appropriate behavioral responses. While much has been learned about how olfactory sensory neurons detect odorants and signal their presence, how specific innate, unlearned behaviors are initiated in response to ethologically relevant odors remains poorly understood. Here, we show that the 4-transmembrane protein CD20, also known as MS4A1, is expressed in a previously uncharacterized subpopulation of olfactory sensory neurons in the main olfactory epithelium of the murine nasal cavity and functions as a mammalian odorant receptor that recognizes compounds produced by mouse predators. While wild-type mice avoid these predator odorants, mice genetically deleted of CD20 do not appropriately respond. Together, this work reveals a novel CD20-mediated odor-sensing mechanism in the mammalian olfactory system that triggers innate behaviors critical for organismal survival.
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Affiliation(s)
- Hao-Ching Jiang
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Sung Jin Park
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - I-Hao Wang
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Interdisciplinary Graduate Program, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Daniel M Bear
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Current Affiliation: Wu Tsai Neurosciences Institute, Stanford University, Palo Alto, CA, USA
| | - Alexandra Nowlan
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- Current affiliation: Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Paul L Greer
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
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Jiang HC, Park SJ, Wang IH, Bear DM, Nowlan A, Greer PL. CD20 is a mammalian odorant receptor expressed in a subset of olfactory sensory neurons that mediates innate avoidance of predators. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.08.552498. [PMID: 37609248 PMCID: PMC10441374 DOI: 10.1101/2023.08.08.552498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
The mammalian olfactory system detects and discriminates between millions of odorants to elicit appropriate behavioral responses. While much has been learned about how olfactory sensory neurons detect odorants and signal their presence, how specific innate, unlearned behaviors are initiated in response to ethologically relevant odors remains poorly understood. Here, we show that the 4-transmembrane protein CD20, also known as MS4A1, is expressed in a previously uncharacterized subpopulation of olfactory sensory neurons in the main olfactory epithelium of the murine nasal cavity and functions as a mammalian odorant receptor that recognizes compounds produced by mouse predators. While wild-type mice avoid these predator odorants, mice genetically deleted of CD20 do not appropriately respond. Together, this work reveals a novel CD20-mediated odor-sensing mechanism in the mammalian olfactory system that triggers innate behaviors critical for organismal survival.
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Ojha NK, Zufall F, Leinders-Zufall T. Optical Activation of Photoswitchable TRPC Ligands in the Mammalian Olfactory System Using Laser Scanning Confocal Microscopy. Methods Mol Biol 2023; 2710:31-47. [PMID: 37688722 DOI: 10.1007/978-1-0716-3425-7_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/11/2023]
Abstract
The transient receptor potential canonical (TRPC) ion channels play important biological roles, but their activation mechanisms are incompletely understood. Here, we describe recent methodological advances using small molecular probes designed for photopharmacology of TRPC channels by focusing on results obtained from the mouse olfactory system. These studies developed and used photoswitchable diacylglycerol (DAG) analogs for ultrarapid activation of native TRPC2 channels in vomeronasal sensory neurons and type B cells of the main olfactory epithelium. Further studies investigated the role of TRPC5 channels in prolactin regulation of dopamine neurons in the arcuate nucleus of the hypothalamus. Here, the first photoswitchable TRPC5 modulator, BTDAzo, was developed and shown to control endogenous TRPC5-based neuronal Ca2+ responses in mouse brain slices. Thus, photoswitchable reagents are rapidly gaining widespread recognition for investigating various types of TRPC channels including TRPC2, TRPC3, TRPC5, and TRPC6, enabling to gain new insights into the gating mechanisms and functions of these channels.
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Affiliation(s)
- Navin K Ojha
- Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Frank Zufall
- Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany.
| | - Trese Leinders-Zufall
- Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany.
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The role of ciliopathy-associated type 3 adenylyl cyclase in infanticidal behavior in virgin adult male mice. iScience 2022; 25:104534. [PMID: 35754726 PMCID: PMC9218507 DOI: 10.1016/j.isci.2022.104534] [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: 10/29/2021] [Revised: 02/11/2022] [Accepted: 06/01/2022] [Indexed: 12/04/2022] Open
Abstract
Virgin adult male mice often display killing of alien newborns, defined as infanticide, and this behavior is dependent on olfactory signaling. Olfactory perception is achieved by the main olfactory system (MOS) or vomeronasal system (VNS). Although it has been established that the VNS is crucial for infanticide in male mice, the role of the MOS in infanticide remains unknown. Herein, by producing lesions via ZnSO4 perfusion and N-methyl-D-aspartic acid stereotactic injection, we demonstrated that the main olfactory epithelium (MOE), anterior olfactory nucleus (AON), or ventromedial hypothalamus (VMH) is crucial for infanticide in adult males. By using CRISPR-Cas9 coupled with adeno-associated viruses to induce specific knockdown of type 3 adenylyl cyclase (AC3) in these tissues, we further demonstrated that AC3, a ciliopathy-associated protein, in the MOE and the expression of related proteins in the AON or VMH are necessary for infanticidal behavior in virgin adult male mice. MOE lesions and knockdown of AC3 in the MOE result in abnormal infanticidal behavior The infanticidal behavior of male mice is impaired by lesioning of the AON or VMH AC3 knockdown in the AON or VMH affects the infanticidal behavior of male mice
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Ruiz Tejada Segura ML, Abou Moussa E, Garabello E, Nakahara TS, Makhlouf M, Mathew LS, Wang L, Valle F, Huang SSY, Mainland JD, Caselle M, Osella M, Lorenz S, Reisert J, Logan DW, Malnic B, Scialdone A, Saraiva LR. A 3D transcriptomics atlas of the mouse nose sheds light on the anatomical logic of smell. Cell Rep 2022; 38:110547. [PMID: 35320714 PMCID: PMC8995392 DOI: 10.1016/j.celrep.2022.110547] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/26/2022] [Accepted: 03/01/2022] [Indexed: 12/26/2022] Open
Abstract
The sense of smell helps us navigate the environment, but its molecular architecture and underlying logic remain understudied. The spatial location of odorant receptor genes (Olfrs) in the nose is thought to be independent of the structural diversity of the odorants they detect. Using spatial transcriptomics, we create a genome-wide 3D atlas of the mouse olfactory mucosa (OM). Topographic maps of genes differentially expressed in space reveal that both Olfrs and non-Olfrs are distributed in a continuous and overlapping fashion over at least five broad zones in the OM. The spatial locations of Olfrs correlate with the mucus solubility of the odorants they recognize, providing direct evidence for the chromatographic theory of olfaction. This resource resolves the molecular architecture of the mouse OM and will inform future studies on mechanisms underlying Olfr gene choice, axonal pathfinding, patterning of the nervous system, and basic logic for the peripheral representation of smell.
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Affiliation(s)
- Mayra L Ruiz Tejada Segura
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany; Institute of Functional Epigenetics, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany; Institute of Computational Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | | | - Elisa Garabello
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany; Physics Department, University of Turin and INFN, Via P. Giuria 1, 10125 Turin, Italy; Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Thiago S Nakahara
- Department of Biochemistry, University of São Paulo, São Paulo, Brazil
| | | | | | - Li Wang
- Sidra Medicine, P.O. Box 26999, Doha, Qatar
| | - Filippo Valle
- Physics Department, University of Turin and INFN, Via P. Giuria 1, 10125 Turin, Italy
| | | | - Joel D Mainland
- Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA; Department of Neuroscience, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michele Caselle
- Physics Department, University of Turin and INFN, Via P. Giuria 1, 10125 Turin, Italy
| | - Matteo Osella
- Physics Department, University of Turin and INFN, Via P. Giuria 1, 10125 Turin, Italy
| | - Stephan Lorenz
- Sidra Medicine, P.O. Box 26999, Doha, Qatar; Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Johannes Reisert
- Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA
| | - Darren W Logan
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Bettina Malnic
- Department of Biochemistry, University of São Paulo, São Paulo, Brazil
| | - Antonio Scialdone
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Feodor-Lynen-Strasse 21, 81377 München, Germany; Institute of Functional Epigenetics, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany; Institute of Computational Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany.
| | - Luis R Saraiva
- Sidra Medicine, P.O. Box 26999, Doha, Qatar; Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA; College of Health and Life Sciences, Hamad Bin Khalifa University, P.O. Box 34110, Doha, Qatar.
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7
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Pfau D, Jordan CL, Breedlove SM. The De-Scent of Sexuality: Did Loss of a Pheromone Signaling Protein Permit the Evolution of Same-Sex Sexual Behavior in Primates? ARCHIVES OF SEXUAL BEHAVIOR 2021; 50:2267-2276. [PMID: 31016493 DOI: 10.1007/s10508-018-1377-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 05/15/2023]
Abstract
Primate same-sex sexual behavior (SSSB) is rarely observed in strepsirrhine species, and only somewhat more common in platyrrhines, but is observed in nearly all catarrhine species, including humans, suggesting the common catarrhine ancestor as the origin of routine SSSB. In mice, disruption of the transient receptor potential cation channel 2 (TRPC2) gene, which is crucial for transducing chemosensory signals from pheromones in the vomeronasal organ, greatly increased the likelihood of SSSB. We note that catarrhine primates share a common deleterious mutation in this gene, indicating that the protein was dysfunctional in the common catarrhine ancestral primate approximately 25 mya (million years ago). We hypothesize that the loss of this protein for processing pheromonal signals in males and females made SSSB more likely in a primate ancestral species by effectively lifting a pheromonally mediated barrier to SSSB and that this was an important precursor to the evolution of such behavior in humans. Additional comparisons between SSSB and the functional status of the TRPC2 gene or related proteins across primate species could lend support to or falsify this hypothesis. Our current research indicates that loss of TRPC2 function in developing mice leads to the loss or attenuation of sexually dimorphisms in the adult brain, which may help us to understand the biological underpinnings of SSSB. Our hypothesis offers an ultimate evolutionary explanation for SSSB in humans.
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Affiliation(s)
- Daniel Pfau
- Neuroscience Program, Michigan State University, Giltner Hall, 293 Farm Lane, Room 108, East Lansing, MI, 48824-1101, USA.
| | - Cynthia L Jordan
- Neuroscience Program, Michigan State University, Giltner Hall, 293 Farm Lane, Room 108, East Lansing, MI, 48824-1101, USA
| | - S Marc Breedlove
- Neuroscience Program, Michigan State University, Giltner Hall, 293 Farm Lane, Room 108, East Lansing, MI, 48824-1101, USA
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Manzini I, Schild D, Di Natale C. Principles of odor coding in vertebrates and artificial chemosensory systems. Physiol Rev 2021; 102:61-154. [PMID: 34254835 DOI: 10.1152/physrev.00036.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The biological olfactory system is the sensory system responsible for the detection of the chemical composition of the environment. Several attempts to mimic biological olfactory systems have led to various artificial olfactory systems using different technical approaches. Here we provide a parallel description of biological olfactory systems and their technical counterparts. We start with a presentation of the input to the systems, the stimuli, and treat the interface between the external world and the environment where receptor neurons or artificial chemosensors reside. We then delineate the functions of receptor neurons and chemosensors as well as their overall I-O relationships. Up to this point, our account of the systems goes along similar lines. The next processing steps differ considerably: while in biology the processing step following the receptor neurons is the "integration" and "processing" of receptor neuron outputs in the olfactory bulb, this step has various realizations in electronic noses. For a long period of time, the signal processing stages beyond the olfactory bulb, i.e., the higher olfactory centers were little studied. Only recently there has been a marked growth of studies tackling the information processing in these centers. In electronic noses, a third stage of processing has virtually never been considered. In this review, we provide an up-to-date overview of the current knowledge of both fields and, for the first time, attempt to tie them together. We hope it will be a breeding ground for better information, communication, and data exchange between very related but so far little connected fields.
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Affiliation(s)
- Ivan Manzini
- Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Gießen, Gießen, Germany
| | - Detlev Schild
- Institute of Neurophysiology and Cellular Biophysics, University Medical Center, University of Göttingen, Göttingen, Germany
| | - Corrado Di Natale
- Department of Electronic Engineering, University of Rome Tor Vergata, Rome, Italy
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Danger perception and stress response through an olfactory sensor for the bacterial metabolite hydrogen sulfide. Neuron 2021; 109:2469-2484.e7. [PMID: 34186026 DOI: 10.1016/j.neuron.2021.05.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/01/2021] [Accepted: 05/27/2021] [Indexed: 12/11/2022]
Abstract
The olfactory system serves a critical function as a danger detection system to trigger defense responses essential for survival. The cellular and molecular mechanisms that drive such defenses in mammals are incompletely understood. Here, we have discovered an ultrasensitive olfactory sensor for the highly poisonous bacterial metabolite hydrogen sulfide (H2S) in mice. An atypical class of sensory neurons in the main olfactory epithelium, the type B cells, is activated by both H2S and low O2. These two stimuli trigger, respectively, Cnga2- and Trpc2-signaling pathways, which operate in separate subcellular compartments, the cilia and the dendritic knob. This activation drives essential defensive responses: elevation of the stress hormone ACTH, stress-related self-grooming behavior, and conditioned place avoidance. Our findings identify a previously unknown signaling paradigm in mammalian olfaction and define type B cells as chemosensory neurons that integrate distinct danger inputs from the external environment with appropriate defense outputs.
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Zimmerman AD, Munger SD. Olfactory subsystems associated with the necklace glomeruli in rodents. Cell Tissue Res 2021; 383:549-557. [PMID: 33404845 DOI: 10.1007/s00441-020-03388-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/07/2020] [Indexed: 01/27/2023]
Abstract
The necklace glomeruli are a loosely defined group of glomeruli encircling the caudal main olfactory bulb in rodents. Initially defined by the expression of various immunohistochemical markers, they are now better understood in the context of the specialized chemosensory neurons of the main olfactory epithelium and Grueneberg ganglion that innervate them. It has become clear that the necklace region of the rodent main olfactory bulb is composed of multiple distinct groups of glomeruli, defined at least in part by their afferent inputs. In this review, we will explore the necklace glomeruli and the chemosensory neurons that innervate them.
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Affiliation(s)
- Arthur D Zimmerman
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, PO Box 100267, Gainesville, FL, 32610, USA
- Center for Smell and Taste, University of Florida, PO Box 100127, Gainesville, FL, 32610, USA
- Training Program in Chemosensory Science, University of Florida, PO Box 100127, Gainesville, FL, 32610, USA
| | - Steven D Munger
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, PO Box 100267, Gainesville, FL, 32610, USA.
- Center for Smell and Taste, University of Florida, PO Box 100127, Gainesville, FL, 32610, USA.
- Training Program in Chemosensory Science, University of Florida, PO Box 100127, Gainesville, FL, 32610, USA.
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida College of Medicine, PO Box 100266, Gainesville, FL, 32610, USA.
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Kurian SM, Naressi RG, Manoel D, Barwich AS, Malnic B, Saraiva LR. Odor coding in the mammalian olfactory epithelium. Cell Tissue Res 2021; 383:445-456. [PMID: 33409650 PMCID: PMC7873010 DOI: 10.1007/s00441-020-03327-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/27/2020] [Indexed: 12/31/2022]
Abstract
Noses are extremely sophisticated chemical detectors allowing animals to use scents to interpret and navigate their environments. Odor detection starts with the activation of odorant receptors (ORs), expressed in mature olfactory sensory neurons (OSNs) populating the olfactory mucosa. Different odorants, or different concentrations of the same odorant, activate unique ensembles of ORs. This mechanism of combinatorial receptor coding provided a possible explanation as to why different odorants are perceived as having distinct odors. Aided by new technologies, several recent studies have found that antagonist interactions also play an important role in the formation of the combinatorial receptor code. These findings mark the start of a new era in the study of odorant-receptor interactions and add a new level of complexity to odor coding in mammals.
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Affiliation(s)
| | | | | | | | - Bettina Malnic
- Department of Biochemistry, University of São Paulo, São Paulo, Brazil.
| | - Luis R Saraiva
- Sidra Medicine, Doha, Qatar.
- Monell Chemical Senses Center, Philadelphia, USA.
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar.
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12
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Kalra S, Mittal A, Bajoria M, Mishra T, Maryam S, Sengupta D, Ahuja G. Challenges and possible solutions for decoding extranasal olfactory receptors. FEBS J 2020; 288:4230-4241. [PMID: 33085840 DOI: 10.1111/febs.15606] [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] [Received: 08/04/2020] [Revised: 09/29/2020] [Accepted: 10/13/2020] [Indexed: 12/15/2022]
Abstract
Olfactory receptors are primarily known to be expressed in the olfactory epithelium of the nasal cavity and therefore assist in odor perception. With the advent of high-throughput omics technologies such as tissue microarray or RNA sequencing, a large number of olfactory receptors have been reported to be expressed in the nonolfactory tissues. Although these technologies uncovered the expression of these olfactory receptors in the nonchemosensory tissues, unfortunately, they failed to reveal the information about their cell type of origin. Accurate characterization of the cell types should be the first step towards devising cell type-specific assays for their functional evaluation. Single-cell RNA-sequencing technology resolved some of these apparent limitations and opened new means to interrogate the expression of these extranasal olfactory receptors at the single-cell resolution. Moreover, the availability of large-scale, multi-organ/species single-cell expression atlases offer ample resources for the systematic reannotation of these receptors in a cell type-specific manner. In this Viewpoint article, we discuss some of the technical limitations that impede the in-depth understanding of these extranasal olfactory receptors, with a special focus on odorant receptors. Moreover, we also propose a list of single cell-based omics technologies that could further promulgate the opportunity to decipher the regulatory network that drives the odorant receptors expression at atypical locations.
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Affiliation(s)
- Siddhant Kalra
- Department of Computational Biology, Indraprastha Institute of Information Technology, New Delhi, India, India
| | - Aayushi Mittal
- Department of Computational Biology, Indraprastha Institute of Information Technology, New Delhi, India, India
| | - Manisha Bajoria
- Department of Computational Biology, Indraprastha Institute of Information Technology, New Delhi, India, India
| | - Tripti Mishra
- Pathfinder Research and Training Foundation, Greater Noida, India
| | - Sidrah Maryam
- Department of Computational Biology, Indraprastha Institute of Information Technology, New Delhi, India, India
| | - Debarka Sengupta
- Department of Computational Biology, Indraprastha Institute of Information Technology, New Delhi, India, India.,Department of Computer Science and Engineering, Indraprastha Institute of Information Technology, New Delhi, India, India.,Centre for Artificial Intelligence, Indraprastha Institute of Information Technology, New Delhi, India.,Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Gaurav Ahuja
- Department of Computational Biology, Indraprastha Institute of Information Technology, New Delhi, India, India
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Mohrhardt J, Nagel M, Fleck D, Ben-Shaul Y, Spehr M. Signal Detection and Coding in the Accessory Olfactory System. Chem Senses 2019; 43:667-695. [PMID: 30256909 PMCID: PMC6211456 DOI: 10.1093/chemse/bjy061] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In many mammalian species, the accessory olfactory system plays a central role in guiding behavioral and physiological responses to social and reproductive interactions. Because of its relatively compact structure and its direct access to amygdalar and hypothalamic nuclei, the accessory olfactory pathway provides an ideal system to study sensory control of complex mammalian behavior. During the last several years, many studies employing molecular, behavioral, and physiological approaches have significantly expanded and enhanced our understanding of this system. The purpose of the current review is to integrate older and newer studies to present an updated and comprehensive picture of vomeronasal signaling and coding with an emphasis on early accessory olfactory system processing stages. These include vomeronasal sensory neurons in the vomeronasal organ, and the circuitry of the accessory olfactory bulb. Because the overwhelming majority of studies on accessory olfactory system function employ rodents, this review is largely focused on this phylogenetic order, and on mice in particular. Taken together, the emerging view from both older literature and more recent studies is that the molecular, cellular, and circuit properties of chemosensory signaling along the accessory olfactory pathway are in many ways unique. Yet, it has also become evident that, like the main olfactory system, the accessory olfactory system also has the capacity for adaptive learning, experience, and state-dependent plasticity. In addition to describing what is currently known about accessory olfactory system function and physiology, we highlight what we believe are important gaps in our knowledge, which thus define exciting directions for future investigation.
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Affiliation(s)
- Julia Mohrhardt
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Maximilian Nagel
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - David Fleck
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Yoram Ben-Shaul
- Department of Medical Neurobiology, School of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
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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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15
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Pyrski M, Tusty M, Eckstein E, Oboti L, Rodriguez-Gil DJ, Greer CA, Zufall F. P/Q Type Calcium Channel Cav2.1 Defines a Unique Subset of Glomeruli in the Mouse Olfactory Bulb. Front Cell Neurosci 2018; 12:295. [PMID: 30233329 PMCID: PMC6131590 DOI: 10.3389/fncel.2018.00295] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/16/2018] [Indexed: 11/24/2022] Open
Abstract
Voltage-gated calcium (Cav) channels are a prerequisite for signal transmission at the first olfactory sensory neuron (OSN) synapse within the glomeruli of the main olfactory bulb (MOB). We showed previously that the N-type Cav channel subunit Cav2.2 is present in the vast majority of glomeruli and plays a central role in presynaptic transmitter release. Here, we identify a distinct subset of glomeruli in the MOB of adult mice that is characterized by expression of the P/Q-type channel subunit Cav2.1. Immunolocalization shows that Cav2.1+ glomeruli reside predominantly in the medial and dorsal MOB, and in the vicinity of the necklace glomerular region close to the accessory olfactory bulb. Few glomeruli are detected on the ventral and lateral MOB. Cav2.1 labeling in glomeruli colocalizes with the presynaptic marker vGlut2 in the axon terminals of OSNs. Electron microscopy shows that Cav2.1+ presynaptic boutons establish characteristic asymmetrical synapses with the dendrites of second-order neurons in the glomerular neuropil. Cav2.1+ glomeruli receive axonal input from OSNs that express molecules of canonical OSNs: olfactory marker protein, the ion channel Cnga2, and the phosphodiesterase Pde4a. In the main olfactory epithelium, Cav2.1 labels a distinct subpopulation of OSNs whose distribution mirrors the topography of the MOB glomeruli, that shows the same molecular signature, and is already present at birth. Together, these experiments identify a unique Cav2.1+ multiglomerular domain in the MOB that may form a previously unrecognized olfactory subsystem distinct from other groups of necklace glomeruli that rely on cGMP signaling mechanisms.
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Affiliation(s)
- Martina Pyrski
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
| | - Mahbuba Tusty
- Department of Neuroscience and Department of Neurosurgery, School of Medicine, Yale University, New Haven, CT, United States
| | - Eugenia Eckstein
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
| | - Livio Oboti
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
| | - Diego J. Rodriguez-Gil
- Department of Neuroscience and Department of Neurosurgery, School of Medicine, Yale University, New Haven, CT, United States
| | - Charles A. Greer
- Department of Neuroscience and Department of Neurosurgery, School of Medicine, Yale University, New Haven, CT, United States
| | - Frank Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
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16
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Crespo C, Liberia T, Blasco-Ibáñez JM, Nácher J, Varea E. Cranial Pair I: The Olfactory Nerve. Anat Rec (Hoboken) 2018; 302:405-427. [PMID: 29659152 DOI: 10.1002/ar.23816] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 05/29/2017] [Accepted: 06/15/2017] [Indexed: 12/13/2022]
Abstract
The olfactory nerve constitutes the first cranial pair. Compared with other cranial nerves, it depicts some atypical features. First, the olfactory nerve does not form a unique bundle. The olfactory axons join other axons and form several small bundles or fascicles: the fila olfactoria. These fascicles leave the nasal cavity, pass through the lamina cribrosa of the ethmoid bone and enter the brain. The whole of these fascicles is what is known as the olfactory nerve. Second, the olfactory sensory neurons, whose axons integrate the olfactory nerve, connect the nasal cavity and the brain without any relay. Third, the olfactory nerve is composed by unmyelinated axons. Fourth, the olfactory nerve contains neither Schwann cells nor oligodendrocytes wrapping its axons. But it contains olfactory ensheathing glia, which is a type of glia unique to this nerve. Fifth, the olfactory axons participate in the circuitry of certain spherical structures of neuropil that are unique in the brain: the olfactory glomeruli. Sixth, the axons of the olfactory nerve are continuously replaced and their connections in the central nervous system are remodeled continuously. Therefore, the olfactory nerve is subject to lifelong plasticity. Finally seventh, the olfactory nerve can be a gateway for the direct entrance of viruses, neurotoxins and other xenobiotics to the brain. In the same way, it can be used as a portal of entry to the brain for therapeutic substances, bypassing the blood-brain barrier. In this article, we analyze some features of the anatomy and physiology of the first cranial pair. Anat Rec, 302:405-427, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Carlos Crespo
- Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Spain
| | - Teresa Liberia
- Departments of Neurosurgery and Neuroscience, Yale University School of Medicine, New Haven, Connecticut
| | - José Miguel Blasco-Ibáñez
- Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Spain
| | - Juan Nácher
- Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Spain
| | - Emilio Varea
- Department of Cell Biology, Interdisciplinary Research Structure for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Spain
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17
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Leinders-Zufall T, Storch U, Bleymehl K, Mederos Y Schnitzler M, Frank JA, Konrad DB, Trauner D, Gudermann T, Zufall F. PhoDAGs Enable Optical Control of Diacylglycerol-Sensitive Transient Receptor Potential Channels. Cell Chem Biol 2017; 25:215-223.e3. [PMID: 29276045 DOI: 10.1016/j.chembiol.2017.11.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 10/02/2017] [Accepted: 11/16/2017] [Indexed: 01/09/2023]
Abstract
Diacylglycerol-sensitive transient receptor potential (TRP) channels play crucial roles in a wide variety of biological processes and systems, but their activation mechanism is not well understood. We describe an optical toolkit by which activation and deactivation of these ion channels can be controlled with unprecedented speed and precision through light stimuli. We show that the photoswitchable diacylglycerols PhoDAG-1 and PhoDAG-3 enable rapid photoactivation of two DAG-sensitive TRP channels, Trpc2 and TRPC6, upon stimulation with UV-A light, whereas exposure to blue light terminates channel activation. PhoDAG photoconversion can be applied in heterologous expression systems, in native cells, and even in mammalian tissue slices. Combined laser scanning-controlled photoswitching and Ca2+ imaging enables both large-scale mapping of TRP channel-mediated neuronal activation and localized mapping in small cellular compartments. Light-switchable PhoDAGs provide an important advance to explore the pathophysiological relevance of DAG-sensitive TRP channels in the maintenance of body homeostasis.
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Affiliation(s)
- Trese Leinders-Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Ursula Storch
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Katherin Bleymehl
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Michael Mederos Y Schnitzler
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - James A Frank
- Department of Chemistry, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - David B Konrad
- Department of Chemistry, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Dirk Trauner
- Department of Chemistry, Ludwig-Maximilians-Universität München, 81377 München, Germany; Department of Chemistry, New York University, New York, NY 10003, USA
| | - Thomas Gudermann
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Frank Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany.
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18
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Zhou T, Matsunami H. Lessons from single-cell transcriptome analysis of oxygen-sensing cells. Cell Tissue Res 2017; 372:403-415. [PMID: 28887696 DOI: 10.1007/s00441-017-2682-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 08/07/2017] [Indexed: 12/15/2022]
Abstract
The advent of single-cell RNA-sequencing (RNA-Seq) technology has enabled transcriptome profiling of individual cells. Comprehensive gene expression analysis at the single-cell level has proven to be effective in characterizing the most fundamental aspects of cellular function and identity. This unbiased approach is revolutionary for small and/or heterogeneous tissues like oxygen-sensing cells in identifying key molecules. Here, we review the major methods of current single-cell RNA-Seq technology. We discuss how this technology has advanced the understanding of oxygen-sensing glomus cells in the carotid body and helped uncover novel oxygen-sensing cells and mechanisms in the mice olfactory system. We conclude by providing our perspective on future single-cell RNA-Seq research directed at oxygen-sensing cells.
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Affiliation(s)
- Ting Zhou
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 261 CARL Building, Box 3509, Durham, NC, USA.
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 261 CARL Building, Box 3509, Durham, NC, USA.,Department of Neurobiology and Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC, USA
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19
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Type 3 inositol 1,4,5-trisphosphate receptor is dispensable for sensory activation of the mammalian vomeronasal organ. Sci Rep 2017; 7:10260. [PMID: 28860523 PMCID: PMC5579292 DOI: 10.1038/s41598-017-09638-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/21/2017] [Indexed: 12/31/2022] Open
Abstract
Signal transduction in sensory neurons of the mammalian vomeronasal organ (VNO) involves the opening of the canonical transient receptor potential channel Trpc2, a Ca2+-permeable cation channel that is activated by diacylglycerol and inhibited by Ca2+-calmodulin. There has been a long-standing debate about the extent to which the second messenger inositol 1,4,5-trisphosphate (InsP3) and type 3 InsP3 receptor (InsP3R3) are involved in the opening of Trpc2 channels and in sensory activation of the VNO. To address this question, we investigated VNO function of mice carrying a knockout mutation in the Itpr3 locus causing a loss of InsP3R3. We established a new method to monitor Ca2+ in the endoplasmic reticulum of vomeronasal sensory neurons (VSNs) by employing the GFP-aequorin protein sensor erGAP2. We also performed simultaneous InsP3 photorelease and Ca2+ monitoring experiments, and analysed Ca2+ dynamics, sensory currents, and action potential or field potential responses in InsP3R3-deficient VSNs. Disruption of Itpr3 abolished or minimized the Ca2+ transients evoked by photoactivated InsP3, but there was virtually no effect on sensory activation of VSNs. Therefore, InsP3R3 is dispensable for primary chemoelectrical transduction in mouse VNO. We conclude that InsP3R3 is not required for gating of Trpc2 in VSNs.
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20
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Bleymehl K, Pérez-Gómez A, Omura M, Moreno-Pérez A, Macías D, Bai Z, Johnson RS, Leinders-Zufall T, Zufall F, Mombaerts P. A Sensor for Low Environmental Oxygen in the Mouse Main Olfactory Epithelium. Neuron 2016; 92:1196-1203. [PMID: 27916458 PMCID: PMC5196021 DOI: 10.1016/j.neuron.2016.11.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/21/2016] [Accepted: 10/20/2016] [Indexed: 11/24/2022]
Abstract
Sensing the level of oxygen in the external and internal environments is essential for survival. Organisms have evolved multiple mechanisms to sense oxygen. No function in oxygen sensing has been attributed to any mammalian olfactory system. Here, we demonstrate that low environmental oxygen directly activates a subpopulation of sensory neurons in the mouse main olfactory epithelium. These neurons express the soluble guanylate cyclase Gucy1b2 and the cation channel Trpc2. Low oxygen induces calcium influx in these neurons, and Gucy1b2 and Trpc2 are required for these responses. In vivo exposure of a mouse to low environmental oxygen causes Gucy1b2-dependent activation of olfactory bulb neurons in the vicinity of the glomeruli formed by axons of Gucy1b2+ sensory neurons. Low environmental oxygen also induces conditioned place aversion, for which Gucy1b2 and Trpc2 are required. We propose that this chemosensory function enables a mouse to rapidly assess the oxygen level in the external environment.
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Affiliation(s)
- Katherin Bleymehl
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Anabel Pérez-Gómez
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Masayo Omura
- Max Planck Research Unit for Neurogenetics, 60438 Frankfurt, Germany
| | - Ana Moreno-Pérez
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - David Macías
- Department of Physiology, Development & Neuroscience, University of Cambridge, Physiological Laboratory, Cambridge CB2 3EG, UK
| | - Zhaodai Bai
- Max Planck Research Unit for Neurogenetics, 60438 Frankfurt, Germany
| | - Randall S Johnson
- Department of Physiology, Development & Neuroscience, University of Cambridge, Physiological Laboratory, Cambridge CB2 3EG, UK; Department of Cell and Molecular Biology, Karolinska Institute, 171 77 Stockholm, Sweden
| | - Trese Leinders-Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Frank Zufall
- Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany.
| | - Peter Mombaerts
- Max Planck Research Unit for Neurogenetics, 60438 Frankfurt, Germany.
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21
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Neuropilin-1 and the Positions of Glomeruli in the Mouse Olfactory Bulb. eNeuro 2016; 3:eN-NWR-0123-16. [PMID: 27844052 PMCID: PMC5089123 DOI: 10.1523/eneuro.0123-16.2016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 09/26/2016] [Accepted: 09/30/2016] [Indexed: 11/21/2022] Open
Abstract
It is known since 1996 that mouse odorant receptors (ORs) are involved in determining the positions of the sites of coalescence of axons of olfactory sensory neurons (OSNs)—the thousands of glomeruli in the olfactory bulb. But the molecular and cellular mechanisms of OR-mediated axonal coalescence into glomeruli remain unclear. A model was proposed in 2006–2009 whereby OR-derived cAMP signals, rather than direct action of OR molecules, determine the target destinations (glomeruli) of OSNs in the bulb. This model hypothesizes that OR-derived cAMP signals determine the expression levels of neuropilin 1 (Nrp1) in OSN axon termini; that levels of Nrp1 in glomeruli form a gradient from anterior-low to posterior-high throughout the bulb; and that these Nrp1 levels mechanistically determine anterior-posterior patterning of glomeruli. Here, we describe the first independent evaluation of the Nrp1 model since it was formulated a decade ago. We tested the model for the well-characterized mouse OR M71 using our gene-targeted mouse strains, which are publicly available. In contradiction to the model, we observed a variety of configurations for the M71 glomeruli in the conditional Nrp1 knockout. We then reassessed the model for the original OR transgene with which the model was developed, using the same publicly available mouse strains. We discovered that glomerular positions do not undergo the simple anterior shift that has been reported in the conditional Nrp1 knockout for this OR transgene. Taken together, our findings do not support the Nrp1 model for the anterior-posterior patterning of glomerular positions in the olfactory bulb.
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22
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Parrilla M, Chang I, Degl'Innocenti A, Omura M. Expression of homeobox genes in the mouse olfactory epithelium. J Comp Neurol 2016; 524:2713-39. [PMID: 27243442 DOI: 10.1002/cne.24051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 12/16/2015] [Accepted: 05/25/2016] [Indexed: 01/22/2023]
Abstract
Homeobox genes constitute a large family of genes widely studied because of their role in the establishment of the body pattern. However, they are also involved in many other events during development and adulthood. The main olfactory epithelium (MOE) is an excellent model to study neurogenesis in the adult nervous system. Analyses of homeobox genes during development show that some of these genes are involved in the formation and establishment of cell diversity in the MOE. Moreover, the mechanisms of expression of odorant receptors (ORs) constitute one of the biggest enigmas in the field. Analyses of OR promoters revealed the presence of homeodomain binding sites in their sequences. Here we characterize the expression patterns of a set of 49 homeobox genes in the MOE with in situ hybridization. We found that seven of them (Dlx3, Dlx5, Dlx6, Msx1, Meis1, Isl1, and Pitx1) are zonally expressed. The homeobox gene Emx1 is expressed in three guanylate cyclase(+) populations, two located in the MOE and the third one in an olfactory subsystem known as Grüneberg ganglion located at the entrance of the nasal cavity. The homeobox gene Tshz1 is expressed in a unique patchy pattern across the MOE. Our findings provide new insights to guide functional studies that aim to understand the complexity of transcription factor expression and gene regulation in the MOE. J. Comp. Neurol. 524:2713-2739, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Marta Parrilla
- Max Planck Institut für Biophysik, Frankfurt am Main, Germany
| | - Isabelle Chang
- Max Planck Institut für Biophysik, Frankfurt am Main, Germany
| | - Andrea Degl'Innocenti
- Max Planck Institut für Biophysik, Frankfurt am Main, Germany.,Unità di Biologia Cellulare e dello Sviluppo, Dipartimento di Biologia, Università di Pisa, Pisa, Italy
| | - Masayo Omura
- Max Planck Institut für Biophysik, Frankfurt am Main, Germany
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23
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Functional Overexpression of Vomeronasal Receptors Using a Herpes Simplex Virus Type 1 (HSV-1)-Derived Amplicon. PLoS One 2016; 11:e0156092. [PMID: 27195771 PMCID: PMC4873243 DOI: 10.1371/journal.pone.0156092] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/09/2016] [Indexed: 12/01/2022] Open
Abstract
In mice, social behaviors such as mating and aggression are mediated by pheromones and related chemosignals. The vomeronasal organ (VNO) detects olfactory information from other individuals by sensory neurons tuned to respond to specific chemical cues. Receptors expressed by vomeronasal neurons are implicated in selective detection of these cues. Nearly 400 receptor genes have been identified in the mouse VNO, but the tuning properties of individual receptors remain poorly understood, in part due to the lack of a robust heterologous expression system. Here we develop a herpes virus-based amplicon delivery system to overexpress three types of vomeronasal receptor genes and to characterize cell responses to their proposed ligands. Through Ca2+ imaging in native VNO cells we show that virus-induced overexpression of V1rj2, V2r1b or Fpr3 caused a pronounced increase of responsivity to sulfated steroids, MHC-binding peptide or the synthetic hexapeptide W-peptide, respectively. Other related ligands were not recognized by infected individual neurons, indicating a high degree of selectivity by the overexpressed receptor. Removal of G-protein signaling eliminates Ca2+ responses, indicating that the endogenous second messenger system is essential for observing receptor activation. Our results provide a novel expression system for vomeronasal receptors that should be useful for understanding the molecular logic of VNO ligand detection. Functional expression of vomeronasal receptors and their deorphanization provides an essential requirement for deciphering the neural mechanisms controlling behavior.
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24
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Saraiva LR, Ibarra-Soria X, Khan M, Omura M, Scialdone A, Mombaerts P, Marioni JC, Logan DW. Hierarchical deconstruction of mouse olfactory sensory neurons: from whole mucosa to single-cell RNA-seq. Sci Rep 2015; 5:18178. [PMID: 26670777 PMCID: PMC4680959 DOI: 10.1038/srep18178] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/13/2015] [Indexed: 12/16/2022] Open
Abstract
The mouse olfactory mucosa is a complex chemosensory tissue composed of multiple cell types, neuronal and non-neuronal. We have here applied RNA-seq hierarchically, in three steps of decreasing cellular heterogeneity: starting with crude tissue samples dissected from the nose, proceeding to flow-cytometrically sorted pools of mature olfactory sensory neurons (OSNs), and finally arriving at single mature OSNs. We show that 98.9% of intact olfactory receptor (OR) genes are expressed in mature OSNs. We uncover a hitherto unknown bipartition among mature OSNs. We find that 19 of 21 single mature OSNs each express a single intact OR gene abundantly, consistent with the one neuron-one receptor rule. For the 9 single OSNs where the two alleles of the abundantly expressed OR gene exhibit single-nucleotide polymorphisms, we demonstrate that monoallelic expression of the abundantly expressed OR gene is extremely tight. The remaining two single mature OSNs lack OR gene expression but express Trpc2 and Gucy1b2. We establish these two cells as a neuronal cell type that is fundamentally distinct from canonical, OR-expressing OSNs and that is defined by the differential, higher expression of 55 genes. We propose this tiered experimental approach as a paradigm to unravel gene expression in other cellularly heterogeneous systems.
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Affiliation(s)
- Luis R Saraiva
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom.,European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SD, United Kingdom.,Department of Experimental Genetics, Sidra Medical &Research Center, Qatar Foundation, PO Box 26999, Doha, Qatar
| | - Ximena Ibarra-Soria
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom
| | - Mona Khan
- Max Planck Research Unit for Neurogenetics, Max-von-Laue-Strasse 4, 60438 Frankfurt, Germany
| | - Masayo Omura
- Max Planck Research Unit for Neurogenetics, Max-von-Laue-Strasse 4, 60438 Frankfurt, Germany
| | - Antonio Scialdone
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom.,European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SD, United Kingdom
| | - Peter Mombaerts
- Max Planck Research Unit for Neurogenetics, Max-von-Laue-Strasse 4, 60438 Frankfurt, Germany
| | - John C Marioni
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom.,European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SD, United Kingdom
| | - Darren W Logan
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom.,Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA
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25
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Gene Expression Profiles of Main Olfactory Epithelium in Adenylyl Cyclase 3 Knockout Mice. Int J Mol Sci 2015; 16:28320-33. [PMID: 26633363 PMCID: PMC4691054 DOI: 10.3390/ijms161226107] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 01/03/2023] Open
Abstract
Adenylyl Cyclase 3 (AC3) plays an important role in the olfactory sensation-signaling pathway in mice. AC3 deficiency leads to defects in olfaction. However, it is still unknown whether AC3 deficiency affects gene expression or olfactory signal transduction pathways within the main olfactory epithelium (MOE). In this study, gene microarrays were used to screen differentially expressed genes in MOE from AC3 knockout (AC3−/−) and wild-type (AC3+/+) mice. The differentially expressed genes identified were subjected to bioinformatic analysis and verified by qRT-PCR. Gene expression in the MOE from AC3−/− mice was significantly altered, compared to AC3+/+ mice. Of the 41266 gene probes, 3379 had greater than 2-fold fold change in expression levels between AC3−/− and AC3+/+ mice, accounting for 8% of the total gene probes. Of these genes, 1391 were up regulated, and 1988 were down regulated, including 425 olfactory receptor genes, 99 genes that are specifically expressed in the immature olfactory neurons, 305 genes that are specifically expressed in the mature olfactory neurons, and 155 genes that are involved in epigenetic regulation. Quantitative RT-PCR verification of the differentially expressed epigenetic regulation related genes, olfactory receptors, ion transporter related genes, neuron development and differentiation related genes, lipid metabolism and membrane protein transport etc. related genes showed that P75NTR, Hinfp, Gadd45b, and Tet3 were significantly up-regulated, while Olfr370, Olfr1414, Olfr1208, Golf, Faim2, Tsg101, Mapk10, Actl6b, H2BE, ATF5, Kirrrel2, OMP, Drd2etc. were significantly down-regulated. In summary, AC3 may play a role in proximal olfactory signaling and play a role in the regulation of differentially expressed genes in mouse MOE.
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26
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Saraiva LR, Ahuja G, Ivandic I, Syed AS, Marioni JC, Korsching SI, Logan DW. Molecular and neuronal homology between the olfactory systems of zebrafish and mouse. Sci Rep 2015; 5:11487. [PMID: 26108469 PMCID: PMC4480006 DOI: 10.1038/srep11487] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 05/27/2015] [Indexed: 11/09/2022] Open
Abstract
Studies of the two major olfactory organs of rodents, the olfactory mucosa (OM) and the vomeronasal organ (VNO), unraveled the molecular basis of smell in vertebrates. However, some vertebrates lack a VNO. Here we generated and analyzed the olfactory transcriptome of the zebrafish and compared it to the olfactory transcriptomes of mouse to investigate the evolutionary and molecular relationship between single and dual olfactory systems. Our analyses revealed a high degree of molecular conservation, with orthologs of mouse olfactory cell-specific markers and all but one of their chemosensory receptor classes expressed in the single zebrafish olfactory organ. Zebrafish chemosensory receptor genes are expressed across a large dynamic range and their RNA abundance correlates positively with the number of neurons expressing that RNA. Thus we estimate the relative proportions of neuronal sub-types expressing different chemosensory receptors. Receptor repertoire size drives the absolute abundance of different classes of neurons, but we find similar underlying patterns in both species. Finally, we identified novel marker genes that characterize rare neuronal populations in both mouse and zebrafish. In sum, we find that the molecular and cellular mechanisms underpinning olfaction in teleosts and mammals are similar despite 430 million years of evolutionary divergence.
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Affiliation(s)
- Luis R Saraiva
- 1] Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom [2] European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Trust Genome Campus, Hinxton-Cambridge, CB10 1SD, United Kingdom
| | - Gaurav Ahuja
- Institut für Genetik, Universität zu Köln, Cologne, 50674, Germany
| | - Ivan Ivandic
- Institut für Genetik, Universität zu Köln, Cologne, 50674, Germany
| | - Adnan S Syed
- Institut für Genetik, Universität zu Köln, Cologne, 50674, Germany
| | - John C Marioni
- European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Trust Genome Campus, Hinxton-Cambridge, CB10 1SD, United Kingdom
| | | | - Darren W Logan
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton-Cambridge, CB10 1SA, United Kingdom
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Yu CR. TRICK or TRP? What Trpc2(-/-) mice tell us about vomeronasal organ mediated innate behaviors. Front Neurosci 2015; 9:221. [PMID: 26157356 PMCID: PMC4477137 DOI: 10.3389/fnins.2015.00221] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/02/2015] [Indexed: 12/23/2022] Open
Abstract
The vomeronasal organ (VNO) plays an important role in mediating semiochemical communications and social behaviors in terrestrial species. Genetic knockout of individual components in the signaling pathways has been used to probe vomeronasal functions, and has provided much insights into how the VNO orchestrates innate behaviors. However, all data do not agree. In particular, knocking out Trpc2, a member of the TRP family of non-selective cationic channel thought to be the main transduction channel in the VNO, results in a number of fascinating behavioral phenotypes that have not been observed in other animals whose vomeronasal function is disrupted. Recent studies have identified signaling pathways that operate in parallel of Trpc2, raising the possibility that Trpc2 mutant animals may display neomorphic behaviors. In this article, I provide a critical analysis of emerging evidence to reconcile the discrepancies and discuss their implications.
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Affiliation(s)
- C Ron Yu
- Stowers Institute for Medical Research Kansas City, MO, USA ; Department of Anatomy and Cell Biology, University of Kansas Medical Center Kansas City, KS, USA
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