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Zocchi D, Ye ES, Hauser V, O'Connell TF, Hong EJ. Parallel encoding of CO 2 in attractive and aversive glomeruli by selective lateral signaling between olfactory afferents. Curr Biol 2022; 32:4225-4239.e7. [PMID: 36070776 PMCID: PMC9561050 DOI: 10.1016/j.cub.2022.08.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 07/13/2022] [Accepted: 08/10/2022] [Indexed: 12/14/2022]
Abstract
We describe a novel form of selective crosstalk between specific classes of primary olfactory receptor neurons (ORNs) in the Drosophila antennal lobe. Neurotransmitter release from ORNs is driven by two distinct sources of excitation: direct activity derived from the odorant receptor and stimulus-selective lateral signals originating from stereotypic subsets of other ORNs. Consequently, the level of presynaptic neurotransmitter release from an ORN can be significantly dissociated from its firing rate. Stimulus-selective lateral signaling results in the distributed representation of CO2-a behaviorally important environmental cue that directly excites a single ORN class-in multiple olfactory glomeruli, each with distinct response dynamics. CO2-sensitive glomeruli coupled to behavioral attraction respond preferentially to fast changes in CO2 concentration, whereas those coupled to behavioral aversion more closely follow absolute levels of CO2. Behavioral responses to CO2 also depend on the temporal structure of the stimulus: flies walk upwind to fluctuating, but not sustained, pulses of CO2. Stimulus-selective lateral signaling generalizes to additional odors and glomeruli, revealing a subnetwork of lateral interactions between ORNs that reshapes the spatial and temporal structure of odor representations in a stimulus-specific manner.
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Affiliation(s)
- Dhruv Zocchi
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Emily S Ye
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Virginie Hauser
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Thomas F O'Connell
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Elizabeth J Hong
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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2
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Heraud C, Hirschinger T, Baranek E, Larroquet L, Surget A, Sandres F, Lanuque A, Terrier F, Roy J. Detection and Modulation of Olfactory Sensing Receptors in Carnivorous Rainbow Trout ( Oncorhynchus mykiss) Fed from First Feeding with Plant-Based Diet. Int J Mol Sci 2022; 23:ijms23042123. [PMID: 35216238 PMCID: PMC8876700 DOI: 10.3390/ijms23042123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/09/2022] [Accepted: 02/13/2022] [Indexed: 11/17/2022] Open
Abstract
Sense of smell is mediated by diverse families of olfactory sensing receptors, conveying important dietary information, fundamental for growth and survival. The aim of this study was to elucidate the role of the sensory olfactory pathways in the regulation of feeding behavior of carnivorous rainbow trout (RT, Oncorhynchus mykiss), from first feeding until 8 months. Compared to a commercial diet, RT fed with a total plant-based diet showed drastically altered growth performance associated with feed intake from an early stage. Exhaustive examination of an RT genome database identified three vomeronasal type 1 receptor-like (ORA), 10 vomeronasal type 2 receptor-like (OLFC) and 14 main olfactory receptor (MOR) genes, all highly expressed in sensory organs, indicating their potential functionality. Gene expression after feeding demonstrated the importance in olfactory sensing perception of some OLFC (olfcg6) and MOR (mor103, -107, -112, -113, -133) receptor family genes in RT. The gene ora1a showed evidence of involvement in olfactory sensing perception for fish fed with a commercial-like diet, while ora5b, mor118, mor124 and olfch1 showed evidence of involvement in fish fed with a plant-based diet. Results indicated an impact of a plant-based diet on the regulation of olfactory sensing pathways as well as influence on monoaminergic neurotransmission in brain areas related to olfactory-driven behaviors. The overall findings suggest that feeding behavior is mediated through olfactory sensing detection and olfactory-driven behavior pathways in RT.
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3
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Llopis-Giménez A, Caballero-Vidal G, Jacquin-Joly E, Crava CM, Herrero S. Baculovirus infection affects caterpillar chemoperception. Insect Biochem Mol Biol 2021; 138:103648. [PMID: 34536505 DOI: 10.1016/j.ibmb.2021.103648] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 09/11/2021] [Accepted: 09/11/2021] [Indexed: 06/13/2023]
Abstract
Baculoviruses are double-stranded DNA entomopathogenic viruses that infect predominantly insects of the order Lepidoptera. Research in the last decade has started to disentangle the mechanisms underlying the insect-virus interaction, particularly focusing on the effects of the baculovirus infection in the host's physiology. Among crucial physiological functions, olfaction has a key role in reproductive tasks, food source detection and enemy avoidance. In this work, we describe that Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) induces expression changes in some odorant receptors (ORs) - the centrepiece of insect's olfaction - when infecting larvae from its natural host Spodoptera exigua (Lepidoptera: Noctuidae). Different ORs are up-regulated in larvae after SeMNPV infection, and two of them, SexiOR35 and SexiOR23, were selected for further functional characterization by heterologous expression in empty neurons of Drosophila melanogaster coupled to single-sensillum recordings. SexiOR35 appears to be a broadly tuned receptor able to recognise multiple and different chemical compounds. SexiOR23, although correctly expressed in Drosophila neurons, did not display any significant response to a panel of 58 stimuli. Behavioural experiments revealed that larvae infected by SeMNPV exhibit altered olfactory-driven behaviour to diet when it is supplemented with the plant volatiles linalool or estragole, two of the main SexiOR35 ligands, supporting the hypothesis that viral infection triggers changes in host perception through changes in the expression level of specific ORs.
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Affiliation(s)
- Angel Llopis-Giménez
- Department of Genetics, University Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100, Burjassot (València), Spain
| | - Gabriela Caballero-Vidal
- INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, Institute of Ecology and Environmental Sciences of Paris, F78026, Versailles Cedex, France
| | - Emmanuelle Jacquin-Joly
- INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université de Paris, Institute of Ecology and Environmental Sciences of Paris, F78026, Versailles Cedex, France
| | - Cristina Maria Crava
- Department of Genetics, University Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100, Burjassot (València), Spain.
| | - Salvador Herrero
- Department of Genetics, University Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100, Burjassot (València), Spain.
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4
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Jana SC, Dutta P, Jain A, Singh A, Adusumilli L, Girotra M, Kumari D, Shirolikar S, Ray K. Kinesin-2 transports Orco into the olfactory cilium of Drosophila melanogaster at specific developmental stages. PLoS Genet 2021; 17:e1009752. [PMID: 34411092 PMCID: PMC8407544 DOI: 10.1371/journal.pgen.1009752] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 08/31/2021] [Accepted: 07/29/2021] [Indexed: 12/21/2022] Open
Abstract
The cilium, the sensing centre for the cell, displays an extensive repertoire of receptors for various cell signalling processes. The dynamic nature of ciliary signalling indicates that the ciliary entry of receptors and associated proteins must be regulated and conditional. To understand this process, we studied the ciliary localisation of the odour-receptor coreceptor (Orco), a seven-pass transmembrane protein essential for insect olfaction. Little is known about when and how Orco gets into the cilia. Here, using Drosophila melanogaster, we show that the bulk of Orco selectively enters the cilia on adult olfactory sensory neurons in two discrete, one-hour intervals after eclosion. A conditional loss of heterotrimeric kinesin-2 during this period reduces the electrophysiological response to odours and affects olfactory behaviour. We further show that Orco binds to the C-terminal tail fragments of the heterotrimeric kinesin-2 motor, which is required to transfer Orco from the ciliary base to the outer segment and maintain within an approximately four-micron stretch at the distal portion of the ciliary outer-segment. The Orco transport was not affected by the loss of critical intraflagellar transport components, IFT172/Oseg2 and IFT88/NompB, respectively, during the adult stage. These results highlight a novel developmental regulation of seven-pass transmembrane receptor transport into the cilia and indicate that ciliary signalling is both developmentally and temporally regulated.
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Affiliation(s)
- Swadhin Chandra Jana
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal
- * E-mail: (SCJ); , (KR)
| | - Priya Dutta
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Akanksha Jain
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Anjusha Singh
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Lavanya Adusumilli
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Mukul Girotra
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Diksha Kumari
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Seema Shirolikar
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Krishanu Ray
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
- * E-mail: (SCJ); , (KR)
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5
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Jafari S, Henriksson J, Yan H, Alenius M. Stress and odorant receptor feedback during a critical period after hatching regulates olfactory sensory neuron differentiation in Drosophila. PLoS Biol 2021; 19:e3001101. [PMID: 33793547 PMCID: PMC8043390 DOI: 10.1371/journal.pbio.3001101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 04/13/2021] [Accepted: 03/02/2021] [Indexed: 11/19/2022] Open
Abstract
Here, we reveal that the regulation of Drosophila odorant receptor (OR) expression during the pupal stage is permissive and imprecise. We found that directly after hatching an OR feedback mechanism both directs and refines OR expression. We demonstrate that, as in mice, dLsd1 and Su(var)3-9 balance heterochromatin formation to direct OR expression. We show that the expressed OR induces dLsd1 and Su(var)3-9 expression, linking OR level and possibly function to OR expression. OR expression refinement shows a restricted duration, suggesting that a gene regulatory critical period brings olfactory sensory neuron differentiation to an end. Consistent with a change in differentiation, stress during the critical period represses dLsd1 and Su(var)3-9 expression and makes the early permissive OR expression permanent. This induced permissive gene regulatory state makes OR expression resilient to stress later in life. Hence, during a critical period OR feedback, similar to in mouse OR selection, defines adult OR expression in Drosophila.
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Affiliation(s)
- Shadi Jafari
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Johan Henriksson
- Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Hua Yan
- Department of Biology, University of Florida, Gainesville, Florida, United States of America
| | - Mattias Alenius
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Department of Molecular Biology, Umeå University, Umeå, Sweden
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Yang L, Agramonte N, Linthicum KJ, Bloomquist JR. A Survey of Chemoreceptive Responses on Different Mosquito Appendages. J Med Entomol 2021; 58:475-479. [PMID: 32740665 DOI: 10.1093/jme/tjaa154] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Indexed: 06/11/2023]
Abstract
Research on the functions of insect chemoreceptors have primarily focused on antennae (olfactory receptors) and mouthparts (gustatory receptors). However, chemoreceptive sensilla are also present on other appendages, such as the leg tarsi and the anterior wing margin, and their specific roles in chemoreception and mosquito behavior remain largely unknown. In this study, electrophysiological analyses in an electroantennogram recording format were performed on Aedes aegypti (L., Diptera: Culicidae) antennae, mouthparts, tarsi, and wings during exposure to a variety of insect repellent and attractant compounds. The results provide evidence that the tarsi and wings can sense chemicals in a gaseous form, and that the odors produce differing responses on different appendages. The most consistent and strongest response occurred when exposed to triethylamine (TEA). Antennae and mouthparts showed nearly identical responses pattern to all tested compounds, and their rank orders of effectiveness were similar to those of fore- and mid-leg tarsi. Hindleg tarsi only responded to TEA, indicating that the hind legs are not as chemoreceptive. Wings responded to a range of odorants, but with a different rank order and voltage amplitude. Insights gleaned into the function of these appendages in insect chemoreception are discussed.
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Affiliation(s)
- Liu Yang
- Neurotoxicology Laboratory, Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL
| | - Natasha Agramonte
- Neurotoxicology Laboratory, Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL
| | - Kenneth J Linthicum
- USDA, ARS, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL
| | - Jeffrey R Bloomquist
- Neurotoxicology Laboratory, Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL
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Abstract
The majority of insect olfactory receptors belong to two distinct protein families, the ionotropic receptors (IRs), which are related to the ionotropic glutamate receptor family, and the odorant receptors (ORs), which evolved from the gustatory receptor family. Both receptor types assemble to heteromeric ligand-gated cation channels composed of odor-specific receptor proteins and co-receptor proteins. We here present in short the current view on evolution, function, and regulation of IRs and ORs. Special attention is given on how their functional properties can meet the environmental and ecological challenges an insect has to face.
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Affiliation(s)
- Dieter Wicher
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany.
| | - Fabio Miazzi
- Research Group Predators and Toxic Prey, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
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8
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Abstract
With less than a million neurons, the western honeybee Apis mellifera is capable of complex olfactory behaviors and provides an ideal model for investigating the neurophysiology of the olfactory circuit and the basis of olfactory perception and learning. Here, we review the most fundamental aspects of honeybee's olfaction: first, we discuss which odorants dominate its environment, and how bees use them to communicate and regulate colony homeostasis; then, we describe the neuroanatomy and the neurophysiology of the olfactory circuit; finally, we explore the cellular and molecular mechanisms leading to olfactory memory formation. The vastity of histological, neurophysiological, and behavioral data collected during the last century, together with new technological advancements, including genetic tools, confirm the honeybee as an attractive research model for understanding olfactory coding and learning.
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Affiliation(s)
- Marco Paoli
- Research Centre on Animal Cognition, Center for Integrative Biology, CNRS, University of Toulouse, 31062, Toulouse, France.
| | - Giovanni C Galizia
- Department of Neuroscience, University of Konstanz, 78457, Konstanz, Germany.
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9
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Abstract
The sense of smell enables insects to recognize olfactory signals crucial for survival and reproduction. In insects, odorant detection highly depends on the interplay of distinct proteins expressed by specialized olfactory sensory neurons (OSNs) and associated support cells which are housed together in chemosensory units, named sensilla, mainly located on the antenna. Besides odorant-binding proteins (OBPs) and olfactory receptors, so-called sensory neuron membrane proteins (SNMPs) are indicated to play a critical role in the detection of certain odorants. SNMPs are insect-specific membrane proteins initially identified in pheromone-sensitive OSNs of Lepidoptera and are indispensable for a proper detection of pheromones. In the last decades, genome and transcriptome analyses have revealed a wide distribution of SNMP-encoding genes in holometabolous and hemimetabolous insects, with a given species expressing multiple subtypes in distinct cells of the olfactory system. Besides SNMPs having a neuronal expression in subpopulations of OSNs, certain SNMP types were found expressed in OSN-associated support cells suggesting different decisive roles of SNMPs in the peripheral olfactory system. In this review, we will report the state of knowledge of neuronal and non-neuronal members of the SNMP family and discuss their possible functions in insect olfaction.
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Affiliation(s)
- Sina Cassau
- Institute of Biology/Zoology, Department of Animal Physiology, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Jürgen Krieger
- Institute of Biology/Zoology, Department of Animal Physiology, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany.
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10
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Abstract
Extant anuran amphibians originate from an evolutionary intersection eventually leading to fully terrestrial tetrapods. In many ways, they have to deal with exposure to both terrestrial and aquatic environments: (i) phylogenetically, as derivatives of the first tetrapod group that conquered the terrestrial environment in evolution; (ii) ontogenetically, with a development that includes aquatic and terrestrial stages connected via metamorphic remodeling; and (iii) individually, with common changes in habitat during the life cycle. Our knowledge about the structural organization and function of the amphibian olfactory system and its relevance still lags behind findings on mammals. It is a formidable challenge to reveal underlying general principles of circuity-related, cellular, and molecular properties that are beneficial for an optimized sense of smell in water and air. Recent findings in structural organization coupled with behavioral observations could help to understand the importance of the sense of smell in this evolutionarily important animal group. We describe the structure of the peripheral olfactory organ, the olfactory bulb, and higher olfactory centers on a tissue, cellular, and molecular levels. Differences and similarities between the olfactory systems of anurans and other vertebrates are reviewed. Special emphasis lies on adaptations that are connected to the distinct demands of olfaction in water and air environment. These particular adaptations are discussed in light of evolutionary trends, ontogenetic development, and ecological demands.
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Affiliation(s)
- Lukas Weiss
- Institute of Animal Physiology, Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 38, 35392, Giessen, Germany
| | - Ivan Manzini
- Institute of Animal Physiology, Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 38, 35392, Giessen, Germany
| | - Thomas Hassenklöver
- Institute of Animal Physiology, Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 38, 35392, Giessen, Germany.
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11
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Li J, Wang X, Zhang L. Sex pheromones and olfactory proteins in Antheraea moths: A. pernyi and A. polyphemus (Lepidoptera: Saturniidae). Arch Insect Biochem Physiol 2020; 105:e21729. [PMID: 32761939 DOI: 10.1002/arch.21729] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023]
Abstract
Olfaction is essential for regulating the physiological and behavioral actions of insects with specific recognition of various odors. Antheraea moths (Lepidoptera: Saturniidae) possess relatively large bodies and antennae so that they are good subjects for exploring molecular aspects of insect olfaction. Current knowledge of the molecular aspects of Antheraea olfaction is focused on the Chinese tussah silkmoth A. pernyi Guérin-Méneville and another species A. polyphemus (Cramer) in their pheromones, odorant-binding proteins (OBPs), odorant receptors (ORs), odorant receptor coreceptors (ORCOs), sensory neuron membrane proteins (SNMPs), and odorant-degrading enzymes (ODEs). The first insect OBP, SNMP, and ODE were identified from A. polyphemus. This review summarizes the principal findings associated with the olfactory physiology and its molecular components in the two Antheraea species. Three types of olfactory neurons may have specific ORs for three respective sex-pheromone components, with the functional sensitivity and specificity mediated by three respective OBPs. SNMPs and ODEs are likely to play important roles in sex-pheromone detection, inactivation, and degradation. Identification and functional analysis of the olfactory molecules remain to be further performed in A. pernyi, A. polyphemus, and other Antheraea species.
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Affiliation(s)
- Jia Li
- Plant Protection College, Shenyang Agricultural University, Shenyang, China
| | - Xiaoqi Wang
- Plant Protection College, Shenyang Agricultural University, Shenyang, China
| | - Long Zhang
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
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12
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Tan K, Jones SH, Lake BB, Chousal JN, Shum EY, Zhang L, Chen S, Sohni A, Pandya S, Gallo RL, Zhang K, Cook-Andersen H, Wilkinson MF. The role of the NMD factor UPF3B in olfactory sensory neurons. eLife 2020; 9:e57525. [PMID: 32773035 PMCID: PMC7452722 DOI: 10.7554/elife.57525] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/09/2020] [Indexed: 12/13/2022] Open
Abstract
The UPF3B-dependent branch of the nonsense-mediated RNA decay (NMD) pathway is critical for human cognition. Here, we examined the role of UPF3B in the olfactory system. Single-cell RNA-sequencing (scRNA-seq) analysis demonstrated considerable heterogeneity of olfactory sensory neuron (OSN) cell populations in wild-type (WT) mice, and revealed that UPF3B loss influences specific subsets of these cell populations. UPF3B also regulates the expression of a large cadre of antimicrobial genes in OSNs, and promotes the selection of specific olfactory receptor (Olfr) genes for expression in mature OSNs (mOSNs). RNA-seq and Ribotag analyses identified classes of mRNAs expressed and translated at different levels in WT and Upf3b-null mOSNs. Integrating multiple computational approaches, UPF3B-dependent NMD target transcripts that are candidates to mediate the functions of NMD in mOSNs were identified in vivo. Together, our data provides a valuable resource for the olfactory field and insights into the roles of NMD in vivo.
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Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Samantha H Jones
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Blue B Lake
- Department of Bioengineering, University of California, San DiegoSan DiegoUnited States
| | - Jennifer N Chousal
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Eleen Y Shum
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Lingjuan Zhang
- Department of Dermatology, University of California, San DiegoSan DiegoUnited States
| | - Song Chen
- Department of Bioengineering, University of California, San DiegoSan DiegoUnited States
| | - Abhishek Sohni
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Shivam Pandya
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Richard L Gallo
- Department of Dermatology, University of California, San DiegoSan DiegoUnited States
| | - Kun Zhang
- Department of Bioengineering, University of California, San DiegoSan DiegoUnited States
| | - Heidi Cook-Andersen
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
- Division of Biological Sciences, University of California, San DiegoSan DiegoUnited States
| | - Miles F Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
- Institute of Genomic Medicine, University of California, San DiegoSan DiegoUnited States
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13
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Wu Q, Li CX, Liu QM, Guo XX, Shi QM, Zhang HD, Dong YD, Xing D, Zhang YM, Liao CH, Han Q, Zhao TY. RNA interference of odorant receptor CquiOR114/117 affects blood-feeding behavior in Culex quinquefasciatus. Acta Trop 2020; 204:105343. [PMID: 31954135 DOI: 10.1016/j.actatropica.2020.105343] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/25/2019] [Accepted: 01/14/2020] [Indexed: 11/15/2022]
Abstract
The odorant receptors (ORs) play a critical role for mosquitoes in the identification of blood-feeding hosts and other physiological processes. The OR8 subfamily in mosquitoes has been shown to be strongly involved in the detection the mammalian host associated odor, 1-octen-3-ol. CquiOR114/117 has been shown to be an orthologous OR8 in Culex quinquefasciatus Say. In this study, the expression of CquiOR114/117 in the different developmental stages of Cx. quinquefasciatus was detected by the amplification of CquiOR114/117 with real-time fluorescence quantitative polymerase chain reaction (PCR). RNA interference (RNAi) technology was used to interfere with the expression of CquiOR114/117 in females to observe the blood-feeding behavior change. The results showed that the expression level of CquiOR114/117 in the egg-to-pupa stage was significantly lower than that in the adult stage and that the expression level of the female mosquitoes peaked on the third day after emergence. The expression of CquiOR114/117 was significantly decreased in the 2-6 days after the injection of dsRNA compared with the control groups. The analysis of the blood-feeding behavior showed a significant positive correlation between CquiOR114/117 expression and the engorgement rate of the mosquitoes. CquiOR114/117 is speculated to have an effect on the blood-feeding behavior of Cx. quinquefasciatus.
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Affiliation(s)
- Qun Wu
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China; Laboratory of Tropical Veterinary Medicine and Vector Biology, and Hainan Key Laboratory of Sustainable Utilization of Tropical Bioresources, Institute of Tropical Agriculture and Forestry, Hainan University, Hainan 570228, China; Department of Vector Control and Prevention, Hainan Provincial Center for Disease Prevention and Control, Hainan 570203, China
| | - Chun-Xiao Li
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China.
| | - Qin-Mei Liu
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China; Laboratory of Tropical Veterinary Medicine and Vector Biology, and Hainan Key Laboratory of Sustainable Utilization of Tropical Bioresources, Institute of Tropical Agriculture and Forestry, Hainan University, Hainan 570228, China
| | - Xiao-Xia Guo
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Qing-Ming Shi
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China.
| | - Heng-Duan Zhang
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China.
| | - Yan-de Dong
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China.
| | - Dan Xing
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Ying-Mei Zhang
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Cheng-Hong Liao
- Laboratory of Tropical Veterinary Medicine and Vector Biology, and Hainan Key Laboratory of Sustainable Utilization of Tropical Bioresources, Institute of Tropical Agriculture and Forestry, Hainan University, Hainan 570228, China
| | - Qian Han
- Laboratory of Tropical Veterinary Medicine and Vector Biology, and Hainan Key Laboratory of Sustainable Utilization of Tropical Bioresources, Institute of Tropical Agriculture and Forestry, Hainan University, Hainan 570228, China.
| | - Tong-Yan Zhao
- Department of Vector Biology and Control, State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Beijing 100071, China.
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14
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Abstract
Imagine smelling a novel perfume with only one nostril and then smelling it again with the other nostril. Clearly, you can tell that it is the same perfume both times. This simple experiment demonstrates that odor information is shared across both hemispheres to enable perceptual unity. In many sensory systems, perceptual unity is believed to be mediated by inter-hemispheric connections between iso-functional cortical regions. However, in the olfactory system, the underlying neural mechanisms that enable this coordination are unclear because the two olfactory cortices are not topographically organized and do not seem to have homotypic inter-hemispheric mapping. This review presents recent advances in determining which aspects of odor information are processed unilaterally or bilaterally, and how odor information is shared across the two hemispheres. We argue that understanding the mechanisms of inter-hemispheric coordination can provide valuable insights that are hard to achieve when focusing on one hemisphere alone.
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Affiliation(s)
- Tal Dalal
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Nitin Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, 208016, India
| | - Rafi Haddad
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
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15
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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Dekel A, Yakir E, Bohbot JD. The sulcatone receptor of the strict nectar-feeding mosquito Toxorhynchites amboinensis. Insect Biochem Mol Biol 2019; 111:103174. [PMID: 31129164 DOI: 10.1016/j.ibmb.2019.05.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/02/2019] [Accepted: 05/23/2019] [Indexed: 06/09/2023]
Abstract
Controlling Ae. aegypti populations and the prevention of mosquito bites includes the development of monitoring, repelling and attract-and-kill strategies that are based on understanding the chemical ecology of these pests. Olfactory-mediated attraction to mammals has recently been linked to the mosquito Aedes aegypti odorant receptor Or4, which is activated by animal-released 6-Methyl-5-hepten-2-one (sulcatone). This odorant is also a major component of flower scents and may play a role outside animal-host seeking. To explore the role of this chemical cue, we looked at the interaction between sulcatone and an Or4 homolog expressed in the antennae of the strict nectar-feeding mosquito Toxorhynchites amboinensis. Using the two-electrode voltage clamp of Xenopus oocytes as a heterologous expression system, we show that this receptor is a high intensity sulcatone receptor comparable to its Aedes counterparts. We also show that OR4 is activated by other aliphatic ketones and is inhibited by DEET. This pharmacological characterization suggests that sulcatone may be operating in more than one context in the Culicidae family.
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Affiliation(s)
- Amir Dekel
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Esther Yakir
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Jonathan D Bohbot
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot, 76100, Israel.
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17
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Abstract
We showed previously (Gorur-Shandilya et al., 2017) that Drosophila olfactory receptor neurons (ORNs) expressing the co-receptor Orco scale their gain inversely with mean odor intensity according to Weber-Fechner's law. Here, we show that this front-end adaptation promotes the reconstruction of odor identity from dynamic odor signals, even in the presence of confounding background odors and rapid intensity fluctuations. These enhancements are further aided by known downstream transformations in the antennal lobe and mushroom body. Our results, which are applicable to various odor classification and reconstruction schemes, stem from the fact that this adaptation mechanism is not intrinsic to the identity of the receptor involved. Instead, a feedback mechanism adjusts receptor sensitivity based on the activity of the receptor-Orco complex, according to Weber-Fechner's law. Thus, a common scaling of the gain across Orco-expressing ORNs may be a key feature of ORN adaptation that helps preserve combinatorial odor codes in naturalistic landscapes.
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Affiliation(s)
- Nirag Kadakia
- Department of Molecular, Cellular and Developmental BiologyYale UniversityNew HavenUnited States
| | - Thierry Emonet
- Department of Molecular, Cellular and Developmental BiologyYale UniversityNew HavenUnited States
- Department of PhysicsYale UniversityNew HavenUnited States
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18
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Mohamed AAM, Retzke T, Das Chakraborty S, Fabian B, Hansson BS, Knaden M, Sachse S. Odor mixtures of opposing valence unveil inter-glomerular crosstalk in the Drosophila antennal lobe. Nat Commun 2019; 10:1201. [PMID: 30867415 PMCID: PMC6416470 DOI: 10.1038/s41467-019-09069-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 02/20/2019] [Indexed: 12/17/2022] Open
Abstract
Evaluating odor blends in sensory processing is a crucial step for signal recognition and execution of behavioral decisions. Using behavioral assays and 2-photon imaging, we have characterized the neural and behavioral correlates of mixture perception in the olfactory system of Drosophila. Mixtures of odors with opposing valences elicit strong inhibition in certain attractant-responsive input channels. This inhibition correlates with reduced behavioral attraction. We demonstrate that defined subsets of GABAergic interneurons provide the neuronal substrate of this computation at pre- and postsynaptic loci via GABAB- and GABAA receptors, respectively. Intriguingly, manipulation of single input channels by silencing and optogenetic activation unveils a glomerulus-specific crosstalk between the attractant- and repellent-responsive circuits. This inhibitory interaction biases the behavioral output. Such a form of selective lateral inhibition represents a crucial neuronal mechanism in the processing of conflicting sensory information.
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Affiliation(s)
- Ahmed A M Mohamed
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
| | - Tom Retzke
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
| | - Sudeshna Das Chakraborty
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
| | - Benjamin Fabian
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
| | - Bill S Hansson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
| | - Markus Knaden
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany
| | - Silke Sachse
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell-Str. 8, 07745, Jena, Germany.
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19
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Houot B, Cazalé-Debat L, Fraichard S, Everaerts C, Saxena N, Sane SP, Ferveur JF. Gene Regulation and Species-Specific Evolution of Free Flight Odor Tracking in Drosophila. Mol Biol Evol 2019; 35:3-15. [PMID: 28961885 DOI: 10.1093/molbev/msx241] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The flying ability of insects has coevolved with the development of organs necessary to take-off from the ground, generate, and modulate lift during flight in complex environments. Flight orientation to the appropriate food source and mating partner depends on the perception and integration of multiple chemical signals. We used a wind tunnel-based assay to investigate the natural and molecular evolution of free flight odor tracking in Drosophila. First, the comparison of female and male flies of several populations and species revealed substantial sex-, inter-, and intra-specific variations for distinct flight features. In these flies, we compared the molecular structure of desat1, a fast-evolving gene involved in multiple aspects of Drosophila pheromonal communication. We manipulated desat1 regulation and found that both neural and nonneural tissues affect distinct flight features. Together, our data suggest that desat1 is one of the genes involved in the evolution of free-flight odor tracking behaviors in Drosophila.
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Affiliation(s)
- Benjamin Houot
- Centre des Sciences du Goût et de l'Alimentation, UMR6265 CNRS, UMR1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
- Division of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Laurie Cazalé-Debat
- Centre des Sciences du Goût et de l'Alimentation, UMR6265 CNRS, UMR1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
| | - Stéphane Fraichard
- Centre des Sciences du Goût et de l'Alimentation, UMR6265 CNRS, UMR1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
| | - Claude Everaerts
- Centre des Sciences du Goût et de l'Alimentation, UMR6265 CNRS, UMR1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
| | - Nitesh Saxena
- Insect Flight Laboratory, National Center for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bangalore, India
| | - Sanjay P Sane
- Insect Flight Laboratory, National Center for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bangalore, India
| | - Jean-François Ferveur
- Centre des Sciences du Goût et de l'Alimentation, UMR6265 CNRS, UMR1324 INRA, Université de Bourgogne Franche-Comté, Dijon, France
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20
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Sharma A, Kumar R, Aier I, Semwal R, Tyagi P, Varadwaj P. Sense of Smell: Structural, Functional, Mechanistic Advancements and Challenges in Human Olfactory Research. Curr Neuropharmacol 2019; 17:891-911. [PMID: 30520376 PMCID: PMC7052838 DOI: 10.2174/1570159x17666181206095626] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/08/2018] [Accepted: 11/28/2018] [Indexed: 02/07/2023] Open
Abstract
Olfaction, the sense of smell detects and discriminate odors as well as social cues which influence our innate responses. The olfactory system in human beings is found to be weak as compared to other animals; however, it seems to be very precise. It can detect and discriminate millions of chemical moieties (odorants) even in minuscule quantities. The process initiates with the binding of odorants to specialized olfactory receptors, encoded by a large family of Olfactory Receptor (OR) genes belonging to the G-protein-coupled receptor superfamily. Stimulation of ORs converts the chemical information encoded in the odorants, into respective neuronal action-potentials which causes depolarization of olfactory sensory neurons. The olfactory bulb relays this signal to different parts of the brain for processing. Odors are encrypted using a combinatorial approach to detect a variety of chemicals and encode their unique identity. The discovery of functional OR genes and proteins provided an important information to decipher the genomic, structural and functional basis of olfaction. ORs constitute 17 gene families, out of which 4 families were reported to contain more than hundred members each. The olfactory machinery is not limited to GPCRs; a number of non- GPCRs is also employed to detect chemosensory stimuli. The article provides detailed information about such olfaction machinery, structures, transduction mechanism, theories of odor perception, and challenges in the olfaction research. It covers the structural, functional and computational studies carried out in the olfaction research in the recent past.
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Affiliation(s)
| | | | | | | | | | - Pritish Varadwaj
- Address correspondence to this author at the Department of Applied Science, Indian Institute of Information Technology, Allahabad, Uttar Pradesh, India; E-mail:
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21
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Li GW, Chen XL, Xu XL, Wu JX. Degradation of sex pheromone and plant volatile components by an antennal glutathione S-transferase in the oriental fruit moth,Grapholita molesta Busck (Lepidoptera: Tortricidae). Arch Insect Biochem Physiol 2018; 99:e21512. [PMID: 30387866 DOI: 10.1002/arch.21512] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 09/14/2018] [Accepted: 09/28/2018] [Indexed: 06/08/2023]
Abstract
Insect antennae have a primary function of perceiving and discerning odorant molecules including sex pheromones and host plant volatiles. The assumption that genes highly expressed in the antennae may have an olfactory-related role associated with signal transduction. Here, one delta subfamily glutathione S-transferase (GST) gene (GmolGSTD1) was obtained from an antennal transcriptome of Grapholita molesta. Quantitative real-time polymerase chain reaction results revealed that GmolGSTD1 was mainly expressed in antennae and the expression levels were significantly higher in female antennae than in male antennae. The recombinant GmolGSTD1 (rGmolGSTD1) showed glutathione-conjugating activity toward 1-chloro-2,4-dinitrobenzene (CDNB) as substrates. The pH range for optimal rGmolGSTD1 enzyme activity was 6.0-6.5, and rGmolGSTD1 enzyme activity had maximal peaks at 35-40°C. Spectrophotometric analysis indicated that insecticides had weak inhibitory effects on the activity of rGmolGSTD1 with the inhibitory rates of 28.82% for chlorpyrifos, 22.27% for lambda-cyhalothrin, 18.07% for bifenthrin, 20.42% for acetamiprid, 17.57% for thiamethoxam, 25.67% for metaflumizone, 27.43% for abamectin, and 7.24% for chlorbenzuron. rGmolGSTD1 exhibited high degradation activity to the sex pheromone component (Z)-8-dodecenyl alcohol and the host plant volatile butyl hexanoate with the degradation efficiency of 75.01% and 48.54%, respectively. We speculate that GmolGSTD1 works in inactivating odorant molecules and maintaining sensitivity to olfactory communication of G. molesta.
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Affiliation(s)
- Guang-Wei Li
- Shaanxi Province Key Laboratory of Jujube, College of Life Science, Yan'an University, Yan'an, China
- Key Laboratory of Plant Protection Resources and Pest Management (Northwest A&F University), Ministry of Education, Yangling, China
| | - Xiu-Lin Chen
- Shaanxi Province Key Laboratory of Jujube, College of Life Science, Yan'an University, Yan'an, China
- Key Laboratory of Plant Protection Resources and Pest Management (Northwest A&F University), Ministry of Education, Yangling, China
| | - Xiang-Li Xu
- Key Laboratory of Plant Protection Resources and Pest Management (Northwest A&F University), Ministry of Education, Yangling, China
- Key Laboratory of Applied Entomology, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Jun-Xiang Wu
- Key Laboratory of Plant Protection Resources and Pest Management (Northwest A&F University), Ministry of Education, Yangling, China
- Key Laboratory of Applied Entomology, College of Plant Protection, Northwest A&F University, Yangling, China
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22
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Chan HK, Hersperger F, Marachlian E, Smith BH, Locatelli F, Szyszka P, Nowotny T. Odorant mixtures elicit less variable and faster responses than pure odorants. PLoS Comput Biol 2018; 14:e1006536. [PMID: 30532147 PMCID: PMC6287832 DOI: 10.1371/journal.pcbi.1006536] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/29/2018] [Indexed: 11/18/2022] Open
Abstract
In natural environments, odors are typically mixtures of several different chemical compounds. However, the implications of mixtures for odor processing have not been fully investigated. We have extended a standard olfactory receptor model to mixtures and found through its mathematical analysis that odorant-evoked activity patterns are more stable across concentrations and first-spike latencies of receptor neurons are shorter for mixtures than for pure odorants. Shorter first-spike latencies arise from the nonlinear dependence of binding rate on odorant concentration, commonly described by the Hill coefficient, while the more stable activity patterns result from the competition between different ligands for receptor sites. These results are consistent with observations from numerical simulations and physiological recordings in the olfactory system of insects. Our results suggest that mixtures allow faster and more reliable olfactory coding, which could be one of the reasons why animals often use mixtures in chemical signaling.
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Affiliation(s)
- Ho Ka Chan
- Sussex Neuroscience, School of Engineering and Informatics, University of Sussex, Falmer, Brighton, United Kingdom
| | - Fabian Hersperger
- Department of Neuroscience, University of Konstanz, Konstanz, Germany
| | - Emiliano Marachlian
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET) and Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
| | - Brian H. Smith
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Fernando Locatelli
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET) and Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
| | - Paul Szyszka
- Department of Neuroscience, University of Konstanz, Konstanz, Germany
| | - Thomas Nowotny
- Sussex Neuroscience, School of Engineering and Informatics, University of Sussex, Falmer, Brighton, United Kingdom
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23
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Jeanne JM, Fişek M, Wilson RI. The Organization of Projections from Olfactory Glomeruli onto Higher-Order Neurons. Neuron 2018; 98:1198-1213.e6. [PMID: 29909998 PMCID: PMC6051339 DOI: 10.1016/j.neuron.2018.05.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 04/19/2018] [Accepted: 05/04/2018] [Indexed: 11/27/2022]
Abstract
Each odorant receptor corresponds to a unique glomerulus in the brain. Projections from different glomeruli then converge in higher brain regions, but we do not understand the logic governing which glomeruli converge and which do not. Here, we use two-photon optogenetics to map glomerular connections onto neurons in the lateral horn, the region of the Drosophila brain that receives the majority of olfactory projections. We identify 39 morphological types of lateral horn neurons (LHNs) and show that different types receive input from different combinations of glomeruli. We find that different LHN types do not have independent inputs; rather, certain combinations of glomeruli converge onto many of the same LHNs and so are over-represented. Notably, many over-represented combinations are composed of glomeruli that prefer chemically dissimilar ligands whose co-occurrence indicates a behaviorally relevant "odor scene." The pattern of glomerulus-LHN connections thus represents a prediction of what ligand combinations will be most salient.
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Affiliation(s)
- James M Jeanne
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Mehmet Fişek
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Rachel I Wilson
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
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24
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Ouedraogo L, den Otter CJ. Comparison of single cell sensitivities to acetone, 1-octen-3-ol and 3-methylphenol in the riverine tsetse species Glossina fuscipes fuscipes and G. palpalis palpalis. J Insect Physiol 2018; 107:144-151. [PMID: 29559304 DOI: 10.1016/j.jinsphys.2018.03.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 03/09/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
Action potentials from individual cells were recorded from antennae (funiculi) of living tsetse flies, Glossina p. palpalis and Glossina f. fuscipes using a "surface-contact" recording technique. Stimuli were vapours of 1-octen-3-ol, acetone and 3-methylphenol. Of the 101 and 128 olfactory cells tested for their sensitivity to odour stimuli in G. p. palpalis and G. f. fuscipes, respectively, the majority (83 and 77%) were activated by more than one chemical. The numbers of these "generalist" cells were 20 and 15% higher in females than in males. Response intensity increased with increasing odour dose. Temporal patterns of excitation were phasic-tonic and showed cells with relatively rapid cessation of spike activity after the end of stimulation and cells which continued firing for several seconds or even minutes after stimulation. Inhibition by odours only occurred in a minority of cells and was dose-dependent. For each of the three substances the excitatory response was significantly higher in G. f. fuscipes than in G. p. palpalis, whereas no significant differences between inhibitory responses were found. In G. f. fuscipes each stimulus evoked equal excitatory responses. In G. p. palpalis, however, acetone induced significantly higher responses than 1-octen-3-ol and 3-methylphenol. Response intensities to each of the three chemicals did not differ between male and female G. p. palpalis, whereas in G. f. fuscipes 1-octen-3-ol evoked significantly higher responses in males. Possible mechanisms of receptor cell odour coding and behavioural effects of the various cell type activities are discussed.
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Affiliation(s)
- Lamini Ouedraogo
- Laboratoire de Physiologie Animale, Unité de Formation et de la Recherche en Sciences de la Vie et de la Terre (UFR/SVT), Universite Ouaga I Pr Joseph KI-ZERBO, Burkina Faso.
| | - C J den Otter
- FRES, Rijksstraatweg 377, 9752 CH Haren, The Netherlands.
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25
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Abstract
Ionotropic receptors (IRs), which form ion channels, can be categorized into conserved 'antennal IRs', which define the first olfactory receptor family of insects, and species-specific 'divergent IRs', which are expressed in gustatory receptor neurones. These receptors are located primarily in cell bodies and dendrites, and are highly enriched in the tips of the dendritic terminals that convey sensory information to higher brain centres. Antennal IRs play important roles in odour and thermosensation, whereas divergent IRs are involved in other important biological processes such as taste sensation. Some IRs are known to play specific biological roles in the perception of various molecules; however, many of their functions have not yet been defined. Although progress has been made in this field, many functions and mechanisms of these receptors remain unknown. In this review, we provide a comprehensive summary of the current state of knowledge in this field.
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Affiliation(s)
- S Rimal
- Department of Bio and Fermentation Convergence Technology, BK21 PLUS Project, Kookmin University, Seoul, Republic of Korea
| | - Y Lee
- Department of Bio and Fermentation Convergence Technology, BK21 PLUS Project, Kookmin University, Seoul, Republic of Korea
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26
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Dang P, Fisher SA, Stefanik DJ, Kim J, Raper JA. Coordination of olfactory receptor choice with guidance receptor expression and function in olfactory sensory neurons. PLoS Genet 2018; 14:e1007164. [PMID: 29385124 PMCID: PMC5809090 DOI: 10.1371/journal.pgen.1007164] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/12/2018] [Accepted: 12/25/2017] [Indexed: 11/18/2022] Open
Abstract
Olfactory sensory neurons choose to express a single odorant receptor (OR) from a large gene repertoire and extend axons to reproducible, OR-specific locations within the olfactory bulb. This developmental process produces a topographically organized map of odorant experience in the brain. The axon guidance mechanisms that generate this pattern of connectivity, as well as those that coordinate OR choice and axonal guidance receptor expression, are incompletely understood. We applied the powerful approach of single-cell RNA-seq on newly born olfactory sensory neurons (OSNs) in young zebrafish larvae to address these issues. Expression profiles were generated for 56 individual Olfactory Marker Protein (OMP) positive sensory neurons by single-cell (SC) RNA-seq. We show that just as in mouse OSNs, mature zebrafish OSNs typically express a single predominant OR transcript. Our previous work suggests that OSN targeting is related to the OR clade from which a sensory neuron chooses to express its odorant receptor. We categorized each of the mature cells based on the clade of their predominantly expressed OR. Transcripts expressed at higher levels in each of three clade-related categories were identified using Penalized Linear Discriminant Analysis (PLDA). A genome-wide approach was used to identify membrane-associated proteins that are most likely to have guidance-related activity. We found that OSNs that choose to express an OR from a particular clade also express specific subsets of potential axon guidance genes and transcription factors. We validated our identification of candidate axon guidance genes for one clade of OSNs using bulk RNA-seq from a subset of transgene-labeled neurons that project to a single protoglomerulus. The differential expression patterns of selected candidate guidance genes were confirmed using fluorescent in situ hybridization. Most importantly, we observed axonal mistargeting in knockouts of three candidate axonal guidance genes identified in this analysis: nrp1a, nrp1b, and robo2. In each case, targeting errors were detected in the subset of axons that normally express these transcripts at high levels, and not in the axons that express them at low levels. Our findings demonstrate that specific, functional, axonal guidance related genes are expressed in subsets of OSNs that that can be categorized by their patterns of OR expression.
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Affiliation(s)
- Puneet Dang
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, United States of America
| | - Stephen A. Fisher
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Derek J. Stefanik
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Junhyong Kim
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Jonathan A. Raper
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, United States of America
- * E-mail:
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Zhang XY, Zhu XQ, Gu SH, Zhou YL, Wang SY, Zhang YJ, Guo YY. Silencing of odorant binding protein gene AlinOBP4 by RNAi induces declining electrophysiological responses of Adelphocoris lineolatus to six semiochemicals. Insect Sci 2017; 24:789-797. [PMID: 27265520 DOI: 10.1111/1744-7917.12365] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/04/2016] [Indexed: 06/05/2023]
Abstract
Odorant binding proteins (OBPs) are believed to be important for transporting semiochemicals through the aqueous sensillar lymph to the olfactory receptor cells within the insect antennal sensilla. Here, we injected AlinOBP4-siRNA into the conjunctivum between prothorax and mesothorax of the lucerne plant bug, Adelphocoris lineolatus and evaluated the silencing of AlinOBP4 by reverse transcription polymerase chain reaction (RT-PCR) analysis, quantitative real-time PCR (qPCR) test and electroantennogram (EAG) assay. The combination of RT-PCR and qPCR analyses revealed that the levels of messenger RNA transcript were significantly reduced ∼95% in AlinOBP4-siRNA-treated A. lineolatus males and ∼75% in RNAi-treated females within 48 hours. It was found that there are different EAG responses between male and female bugs when the AlinOBP4 gene was silenced by RNAi. The EAGs of A. lineolatus to two plant volatiles, tridecanal and hexyl alcohol, were reduced 9.09% and 79.45% in RNAi-treated males, 62.08% and 62.08% in RNAi-treated females compared to the controls, separately. Antennae of RNAi-treated bugs showed significantly lower electrophysiological responses to four sex pheromone analogs, butyl butanoate, 1-hexyl butyrate, (E)-2-hexenyl butyrate and hexyl hexanoate. The EAG recordings were reduced 35.43%, 35.24%, 39.96% and 78.47% in RNAi-treated males and 64.52%, 18.13%, 36.88% and 49.52% in RNAi-treated females, respectively. The results suggested that AlinOBP4 might play dual-roles in the identification of plant volatiles and sex pheromones. It was suspected that AlinOBP4 may have different functions in odor perception between male and female A. lineolatus.
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Affiliation(s)
- Xue-Ying Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiao-Qiang Zhu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Shao-Hua Gu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yan-Le Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Song-Ying Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yong-Jun Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yu-Yuan Guo
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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28
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Pask GM, Slone JD, Millar JG, Das P, Moreira JA, Zhou X, Bello J, Berger SL, Bonasio R, Desplan C, Reinberg D, Liebig J, Zwiebel LJ, Ray A. Specialized odorant receptors in social insects that detect cuticular hydrocarbon cues and candidate pheromones. Nat Commun 2017; 8:297. [PMID: 28819196 PMCID: PMC5561057 DOI: 10.1038/s41467-017-00099-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 06/01/2017] [Indexed: 11/17/2022] Open
Abstract
Eusocial insects use cuticular hydrocarbons as components of pheromones that mediate social behaviours, such as caste and nestmate recognition, and regulation of reproduction. In ants such as Harpegnathos saltator, the queen produces a pheromone which suppresses the development of workers' ovaries and if she is removed, workers can transition to a reproductive state known as gamergate. Here we functionally characterize a subfamily of odorant receptors (Ors) with a nine-exon gene structure that have undergone a massive expansion in ants and other eusocial insects. We deorphanize 22 representative members and find they can detect cuticular hydrocarbons from different ant castes, with one (HsOr263) that responds strongly to gamergate extract and a candidate queen pheromone component. After systematic testing with a diverse panel of hydrocarbons, we find that most Harpegnathos saltator Ors are narrowly tuned, suggesting that several receptors must contribute to detection and discrimination of different cuticular hydrocarbons important in mediating eusocial behaviour.Cuticular hydrocarbons (CHC) mediate the interactions between individuals in eusocial insects, but the sensory receptors for CHCs are unclear. Here the authors show that in ants such as H. saltator, the 9-exon subfamily of odorant receptors (HsOrs) responds to CHCs, and ectopic expression of HsOrs in Drosophila neurons imparts responsiveness to CHCs.
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Affiliation(s)
- Gregory M Pask
- Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA
| | - Jesse D Slone
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA
| | - Jocelyn G Millar
- Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA
| | - Prithwiraj Das
- Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA
| | - Jardel A Moreira
- Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA
| | - Xiaofan Zhou
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA
| | - Jan Bello
- Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA
| | - Shelley L Berger
- Department of Cell and Developmental Biology, Epigenetics Program, University of Pennsylvania School of Medicine, Philadelphia, PA, 19104, USA
| | - Roberto Bonasio
- Department of Cell and Developmental Biology, Epigenetics Program, University of Pennsylvania School of Medicine, Philadelphia, PA, 19104, USA
| | - Claude Desplan
- Department of Biology, New York University, New York, NY, 10003, USA
| | - Danny Reinberg
- Department of Biochemistry and Howard Hughes Medical Institute, New York University School of Medicine, New York, NY, 10016, USA
| | - Jürgen Liebig
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA
| | - Laurence J Zwiebel
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA
| | - Anandasankar Ray
- Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA.
- Center for Disease Vector Research, University of California Riverside, Riverside, CA, 92521, USA.
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29
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Wolf S, Gelis L, Dörrich S, Hatt H, Kraft P. Evidence for a shape-based recognition of odorants in vivo in the human nose from an analysis of the molecular mechanism of lily-of-the-valley odorants detection in the Lilial and Bourgeonal family using the C/Si/Ge/Sn switch strategy. PLoS One 2017; 12:e0182147. [PMID: 28763484 PMCID: PMC5538716 DOI: 10.1371/journal.pone.0182147] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 07/13/2017] [Indexed: 01/20/2023] Open
Abstract
We performed an analysis of possible mechanisms of ligand recognition in the human nose. The analysis is based on in vivo odor threshold determination and in vitro Ca2+ imaging assays with a C/Si/Ge/Sn switch strategy applied to the compounds Lilial and Bourgeonal, to differentiate between different molecular mechanisms of odorant detection. Our results suggest that odorant detection under threshold conditions is mainly based on the molecular shape, i.e. the van der Waals surface, and electrostatics of the odorants. Furthermore, we show that a single olfactory receptor type is responsible for odor detection of Bourgeonal at the threshold level in humans in vivo. Carrying out a QM analysis of vibrational energies contained in the odorants, there is no evidence for a vibration-based recognition.
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Affiliation(s)
- Steffen Wolf
- Department of Biophysics, CAS-MPG Partner Institute for Computational Biology, Key Laboratory of Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, P.R. China
- Department of Biophysics, Ruhr-University Bochum, Bochum, Germany
| | - Lian Gelis
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany
| | - Steffen Dörrich
- Institute of Inorganic Chemistry, University of Würzburg, Würzburg, Germany
| | - Hanns Hatt
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany
| | - Philip Kraft
- Fragrance Research, Givaudan Schweiz AG, Dübendorf, Switzerland
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30
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Liu Q, Liu W, Zeng B, Wang G, Hao D, Huang Y. Deletion of the Bombyx mori odorant receptor co-receptor (BmOrco) impairs olfactory sensitivity in silkworms. Insect Biochem Mol Biol 2017; 86:58-67. [PMID: 28577927 DOI: 10.1016/j.ibmb.2017.05.007] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 04/20/2017] [Accepted: 05/29/2017] [Indexed: 05/14/2023]
Abstract
Olfaction plays an essential role in many important insect behaviors such as feeding and reproduction. To detect olfactory stimuli, an odorant receptor co-receptor (Orco) is required. In this study, we deleted the Orco gene in the Lepidopteran model insect, Bombyx mori, using a binary transgene-based clustered regulatory interspaced short palindromic repeats (CRISPR)/Cas9 system. We initially generated somatic mutations in two targeted sites, from which we obtained homozygous mutants with deletion of a 866 base pair sequence. Because of the flight inability of B. mori, we developed a novel method to examine the adult mating behavior. Considering the specialization in larval feeding, we examined food selection behavior in Orco somatic mutants by the walking trail analysis of silkworm position over time. Single sensillum recordings indicated that the antenna of the homozygous mutant was unable to respond to either of the two sex pheromones, bombykol or bombykal. An adult mating behavior assay revealed that the Orco mutant displayed a significantly impaired mating selection behavior in response to natural pheromone released by a wild-type female moth as well as an 11:1 mixture of bombykol/bombykal. The mutants also exhibited a decreased response to bombykol and, similar to wild-type moths, they displayed no response to bombykal. A larval feeding behavior assay revealed that the Orco mutant displayed defective selection for mulberry leaves and different concentrations of the volatile compound cis-jasmone found in mulberry leaves. Deletion of BmOrco severely disrupts the olfactory system, suggesting that BmOrco is indispensable in the olfactory pathway. The approach used for generating somatic and homozygous mutations also highlights a novel method for mutagenesis. This study on BmOrco function provides insights into the insect olfactory system and also provides a paradigm for agroforestry pest control.
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Affiliation(s)
- Qun Liu
- Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China; College of Forestry, Nanjing Forestry University, Nanjing 210037, China; Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wei Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Baosheng Zeng
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Guirong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Dejun Hao
- Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China; College of Forestry, Nanjing Forestry University, Nanjing 210037, China.
| | - Yongping Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
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31
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Mitchell RF, Hall LP, Reagel PF, McKenna DD, Baker TC, Hildebrand JG. Odorant receptors and antennal lobe morphology offer a new approach to understanding olfaction in the Asian longhorned beetle. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 203:99-109. [PMID: 28078425 DOI: 10.1007/s00359-016-1138-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/28/2016] [Accepted: 12/04/2016] [Indexed: 01/24/2023]
Abstract
The Asian longhorned beetle Anoplophora glabripennis (Motchulsky) is an exotic forest pest that has repeatedly invaded North America and Europe from Asia, and has the potential to kill millions of trees and cause billions of dollars in damage. Traps baited with an attractive mixture of volatile organic compounds from hosts have been of limited success in monitoring invasion sites. We propose that lures might be improved through studying the olfactory system of adult beetles, especially the gene family of odorant receptors (ORs) and the structure of the antennal lobes of the brain. Here, we report identification of 132 ORs in the genome of A. glabripennis (inclusive of one Orco gene and 11 pseudogenes), some of which are orthologous to known pheromone receptors of other cerambycid beetles. We also identified three ORs that are strongly biased toward expression in the female transcriptome, and a single OR strongly biased toward males. Three-dimensional reconstruction of the antennal lobes of adults suggested a male-specific macroglomerulus and several enlarged glomeruli in females. We predict that functional characterization of ORs and glomeruli will lead to identification of key odorants in the life history of A. glabripennis that may aid in monitoring and controlling future invasions.
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Affiliation(s)
- Robert F Mitchell
- Department of Neuroscience, University of Arizona, Tucson, AZ, 85721, USA.
- Center for Insect Science, University of Arizona, Tucson, AZ, 85721, USA.
- Department of Biology, University of Wisconsin Oshkosh, 142 Halsey Science Center, 800 Algoma Blvd., Oshkosh, WI, 54901, USA.
| | - Loyal P Hall
- Department of Entomology, Pennsylvania State University, University Park, PA, 16802, USA
| | | | - Duane D McKenna
- Department of Biological Sciences, University of Memphis, Memphis, TN, 38152, USA
| | - Thomas C Baker
- Department of Entomology, Pennsylvania State University, University Park, PA, 16802, USA
| | - John G Hildebrand
- Department of Neuroscience, University of Arizona, Tucson, AZ, 85721, USA
- Center for Insect Science, University of Arizona, Tucson, AZ, 85721, USA
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32
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Abstract
Earlier experiments demonstrated that in order to place protracted tentacles and thereby olfactory receptors in an appropriate position for optimal perception of odor stimuli extraordinary complex movements are required. Until recently both large scale tentacle movements and patterned tentacle movements have been attributed to the concerted involvement of the tentacle retractor muscle and muscles of tegumentum. Recently the existence of three novel muscles in the posterior tentacles of Helix has been discovered. The present review, based on experimental data obtained by our research group, outlines the anatomy, physiology and pharmacology of these muscles that enable the tentacles to execute complex movements observed during foraging both in naïve and food-conditioned snails. Our findings are also compared as far as possible with earlier and recent data obtained on innervation characteristics and pharmacology of molluscan muscles.
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Affiliation(s)
- Tibor Kiss
- Department of Experimental Zoology, Balaton Limnological Institute, MTA Centre for Ecological Research , H-8237 Tihany , Hungary
| | - Nóra Krajcs
- Department of Experimental Zoology, Balaton Limnological Institute, MTA Centre for Ecological Research , H-8237 Tihany , Hungary
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33
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Dekel A, Pitts RJ, Yakir E, Bohbot JD. Evolutionarily conserved odorant receptor function questions ecological context of octenol role in mosquitoes. Sci Rep 2016; 6:37330. [PMID: 27849027 PMCID: PMC5110965 DOI: 10.1038/srep37330] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 10/11/2016] [Indexed: 11/08/2022] Open
Abstract
Olfaction is a key insect adaptation to a wide range of habitats. In the last thirty years, the detection of octenol by blood-feeding insects has been primarily understood in the context of animal host-seeking. The recent discovery of a conserved octenol receptor gene in the strictly nectar-feeding elephant mosquito Toxorhynchites amboinensis (TaOr8) suggests a different biological role. Here, we show that TaOR8 is a functional ortholog of its counterparts in blood-feeding mosquitoes displaying selectivity towards the (R)-enantiomer of octenol and susceptibility to the insect repellent DEET. These findings suggest that while the function of OR8 has been maintained throughout mosquito evolution, the context in which this receptor is operating has diverged in blood and nectar-feeding mosquitoes.
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Affiliation(s)
- Amir Dekel
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Ronald J. Pitts
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Esther Yakir
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Jonathan D. Bohbot
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot 76100, Israel
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Abstract
The olfactory system removes correlations in natural odors using a network of inhibitory neurons in the olfactory bulb. It has been proposed that this network integrates the response from all olfactory receptors and inhibits them equally. However, how such global inhibition influences the neural representations of odors is unclear. Here, we study a simple statistical model of the processing in the olfactory bulb, which leads to concentration-invariant, sparse representations of the odor composition. We show that the inhibition strength can be tuned to obtain sparse representations that are still useful to discriminate odors that vary in relative concentration, size, and composition. The model reveals two generic consequences of global inhibition: (i) odors with many molecular species are more difficult to discriminate and (ii) receptor arrays with heterogeneous sensitivities perform badly. Comparing these predictions to experiments will help us to understand the role of global inhibition in shaping normalized odor representations in the olfactory bulb.
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Affiliation(s)
- David Zwicker
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, United States of America
- Kavli Institute for Bionano Science and Technology, Harvard University, Cambridge, MA 02138, United States of America
- * E-mail:
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35
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Nolte A, Gawalek P, Koerte S, Wei H, Schumann R, Werckenthin A, Krieger J, Stengl M. No Evidence for Ionotropic Pheromone Transduction in the Hawkmoth Manduca sexta. PLoS One 2016; 11:e0166060. [PMID: 27829053 PMCID: PMC5102459 DOI: 10.1371/journal.pone.0166060] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 10/21/2016] [Indexed: 01/10/2023] Open
Abstract
Insect odorant receptors (ORs) are 7-transmembrane receptors with inverse membrane topology. They associate with the conserved ion channel Orco. As chaperon, Orco maintains ORs in cilia and, as pacemaker channel, Orco controls spontaneous activity in olfactory receptor neurons. Odorant binding to ORs opens OR-Orco receptor ion channel complexes in heterologous expression systems. It is unknown, whether this also occurs in vivo. As an alternative to this ionotropic transduction, experimental evidence is accumulating for metabotropic odor transduction, implicating that insect ORs couple to G-proteins. Resulting second messengers gate various ion channels. They generate the sensillum potential that elicits phasic-tonic action potentials (APs) followed by late, long-lasting pheromone responses. Because it is still unclear how and when Orco opens after odor-OR-binding, we used tip recordings to examine in vivo the effects of the Orco antagonist OLC15 and the amilorides MIA and HMA on bombykal transduction in the hawkmoth Manduca sexta. In contrast to OLC15 both amilorides decreased the pheromone-dependent sensillum potential amplitude and the frequency of the phasic AP response. Instead, OLC15 decreased spontaneous activity, increased latencies of phasic-, and decreased frequencies of late, long-lasting pheromone responses Zeitgebertime-dependently. Our results suggest no involvement for Orco in the primary transduction events, in contrast to amiloride-sensitive channels. Instead of an odor-gated ionotropic receptor, Orco rather acts as a voltage- and apparently second messenger-gated pacemaker channel controlling the membrane potential and hence threshold and kinetics of the pheromone response.
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Affiliation(s)
- Andreas Nolte
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
| | - Petra Gawalek
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
| | - Sarah Koerte
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
| | - HongYing Wei
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
| | - Robin Schumann
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
| | - Achim Werckenthin
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
| | - Jürgen Krieger
- Department of Animal Physiology, Institute of Biology/Zoology, Martin-Luther-University Halle-Wittenberg, Hoher Weg 8, 06108, Halle (Saale), Germany
| | - Monika Stengl
- Department of Animal Physiology, FB 10 Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany
- * E-mail:
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36
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Abstract
Most natural odors have sparse molecular composition. This makes the principles of compressed sensing potentially relevant to the structure of the olfactory code. Yet, the largely feedforward organization of the olfactory system precludes reconstruction using standard compressed sensing algorithms. To resolve this problem, recent theoretical work has shown that signal reconstruction could take place as a result of a low dimensional dynamical system converging to one of its attractor states. However, the dynamical aspects of optimization slowed down odor recognition and were also found to be susceptible to noise. Here we describe a feedforward model of the olfactory system that achieves both strong compression and fast reconstruction that is also robust to noise. A key feature of the proposed model is a specific relationship between how odors are represented at the glomeruli stage, which corresponds to a compression, and the connections from glomeruli to third-order neurons (neurons in the olfactory cortex of vertebrates or Kenyon cells in the mushroom body of insects), which in the model corresponds to reconstruction. We show that should this specific relationship hold true, the reconstruction will be both fast and robust to noise, and in particular to the false activation of glomeruli. The predicted connectivity rate from glomeruli to third-order neurons can be tested experimentally.
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Affiliation(s)
- Yilun Zhang
- Computational Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
- Department of Physics, University of California San Diego, La Jolla, California, United States of America
| | - Tatyana O. Sharpee
- Computational Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
- Department of Physics, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
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37
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Diamond A, Schmuker M, Berna AZ, Trowell S, Nowotny T. Classifying continuous, real-time e-nose sensor data using a bio-inspired spiking network modelled on the insect olfactory system. Bioinspir Biomim 2016; 11:026002. [PMID: 26891474 DOI: 10.1088/1748-3190/11/2/026002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In many application domains, conventional e-noses are frequently outperformed in both speed and accuracy by their biological counterparts. Exploring potential bio-inspired improvements, we note a number of neuronal network models have demonstrated some success in classifying static datasets by abstracting the insect olfactory system. However, these designs remain largely unproven in practical settings, where sensor data is real-time, continuous, potentially noisy, lacks a precise onset signal and accurate classification requires the inclusion of temporal aspects into the feature set. This investigation therefore seeks to inform and develop the potential and suitability of biomimetic classifiers for use with typical real-world sensor data. Taking a generic classifier design inspired by the inhibition and competition in the insect antennal lobe, we apply it to identifying 20 individual chemical odours from the timeseries of responses of metal oxide sensors. We show that four out of twelve available sensors and the first 30 s (10%) of the sensors' continuous response are sufficient to deliver 92% accurate classification without access to an odour onset signal. In contrast to previous approaches, once training is complete, sensor signals can be fed continuously into the classifier without requiring discretization. We conclude that for continuous data there may be a conceptual advantage in using spiking networks, in particular where time is an essential component of computation. Classification was achieved in real time using a GPU-accelerated spiking neural network simulator developed in our group.
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Affiliation(s)
- A Diamond
- School Of Engineering and Informatics, University of Sussex, UK
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He M, Zhang YN, He P. Molecular Characterization and Differential Expression of an Olfactory Receptor Gene Family in the White-Backed Planthopper Sogatella furcifera Based on Transcriptome Analysis. PLoS One 2015; 10:e0140605. [PMID: 26540266 PMCID: PMC4634861 DOI: 10.1371/journal.pone.0140605] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 09/27/2015] [Indexed: 11/18/2022] Open
Abstract
The white-backed planthopper, Sogatella furcifera, a notorious rice pest in Asia, employs host plant volatiles as cues for host location. In insects, odor detection is mediated by two types of olfactory receptors: odorant receptors (ORs) and ionotropic receptors (IRs). In this study, we identified 63 SfurORs and 14 SfurIRs in S. furcifera based on sequences obtained from the head transcriptome and bioinformatics analysis. The motif-pattern of 130 hemiptera ORs indicated an apparent differentiation in this order. Phylogenetic trees of the ORs and IRs were constructed using neighbor-joining estimates. Most of the ORs had orthologous genes, but a specific OR clade was identified in S. furcifera, which suggests that these ORs may have specific olfactory functions in this species. Our results provide a basis for further investigations of how S. furcifera coordinates its olfactory receptor genes with its plant hosts, thereby providing a foundation for novel pest management approaches based on these genes.
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Affiliation(s)
- Ming He
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, P. R. China
| | - Ya-Nan Zhang
- College of Life Sciences, Huaibei Normal University, Huaibei, P. R. China
| | - Peng He
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, P. R. China
- * E-mail: ;
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Lin X, Zhang Q, Wu Z, Du Y. Identification and Differential Expression of a Candidate Sex Pheromone Receptor in Natural Populations of Spodoptera litura. PLoS One 2015; 10:e0131407. [PMID: 26126192 PMCID: PMC4488349 DOI: 10.1371/journal.pone.0131407] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 06/01/2015] [Indexed: 11/18/2022] Open
Abstract
Olfaction is primarily mediated by highly specific olfactory receptors (ORs), a subfamily of which are the pheromone receptors that play a key role in sexual communication and can contribute to reproductive isolation. Here we cloned and identified an olfactory receptor, SlituOR3 (Genbank NO. JN835270), from Spodoptera litura, to be the candidate pheromone receptor. It exhibited male-biased expression in the antennae, where they were localized at the base of sensilla trichoidea. Conserved orthologues of these receptors were found amongst known pheromone receptors within the Lepidoptera, and SlituOR3 were placed amongst a clade of candidate pheromone receptors in a phylogeny tree of insect ORs. SlituOR3 is required for the EAG responses to both Z9E11-14:OAc and Z9E12-14:OAc SlituOR3 showed differential expression in S. litura populations attracted to traps baited with a series of sex pheromone blends composed of different ratios of (9Z,11E)-tetradecadienyl acetate (Z9E11-14:OAc) and (9Z,12E)-tetradecadienyl acetate (Z9E12-14:OAc). The changes in the expression level of SlitOR3 and antennal responses after SlitOR3 silencing suggested that SlitOR3 is required for the sex pheromone signaling. We infer that variation in transcription levels of olfactory receptors may modulate sex pheromone perception in male moths and could affect both of pest control and monitoring efficiency by pheromone application after long time mass trapping with one particular ratio of blend in the field.
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MESH Headings
- Amino Acid Sequence
- Animals
- Arthropod Antennae/physiology
- Base Sequence
- Cloning, Molecular
- DNA, Complementary/genetics
- Female
- Gene Silencing
- Genes, Insect
- Insect Proteins/chemistry
- Insect Proteins/genetics
- Insect Proteins/physiology
- Male
- Molecular Sequence Data
- Phylogeny
- Protein Structure, Tertiary
- Receptors, Odorant/chemistry
- Receptors, Odorant/genetics
- Receptors, Odorant/physiology
- Receptors, Pheromone/chemistry
- Receptors, Pheromone/genetics
- Receptors, Pheromone/physiology
- Sequence Homology, Amino Acid
- Sex Attractants/physiology
- Spodoptera/genetics
- Spodoptera/physiology
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Affiliation(s)
- Xinda Lin
- College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang, China
| | - Qinhui Zhang
- Institute of Health & Environmental Ecology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhongnan Wu
- Institute of Health & Environmental Ecology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yongjun Du
- Institute of Health & Environmental Ecology, Wenzhou Medical University, Wenzhou, Zhejiang, China
- * E-mail:
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40
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Siciliano P, He XL, Woodcock C, Pickett JA, Field LM, Birkett MA, Kalinova B, Gomulski LM, Scolari F, Gasperi G, Malacrida AR, Zhou JJ. Identification of pheromone components and their binding affinity to the odorant binding protein CcapOBP83a-2 of the Mediterranean fruit fly, Ceratitis capitata. Insect Biochem Mol Biol 2014; 48:51-62. [PMID: 24607850 PMCID: PMC4003389 DOI: 10.1016/j.ibmb.2014.02.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 02/17/2014] [Accepted: 02/18/2014] [Indexed: 05/27/2023]
Abstract
The Mediterranean fruit fly (or medfly), Ceratitis capitata (Wiedemann; Diptera: Tephritidae), is a serious pest of agriculture worldwide, displaying a very wide larval host range with more than 250 different species of fruit and vegetables. Olfaction plays a key role in the invasive potential of this species. Unfortunately, the pheromone communication system of the medfly is complex and still not well established. In this study, we report the isolation of chemicals emitted by sexually mature individuals during the "calling" period and the electrophysiological responses that these compounds elicit on the antennae of male and female flies. Fifteen compounds with electrophysiological activity were isolated and identified in male emissions by gas chromatography coupled to electroantennography (GC-EAG). Within the group of 15 identified compounds, 11 elicited a response in antennae of both sexes, whilst 4 elicited a response only in female antennae. The binding affinity of these compounds, plus 4 additional compounds known to be behaviourally active from other studies, was measured using C. capitata OBP, CcapOBP83a-2. This OBP has a high homology to Drosophila melanogaster OBPs OS-E and OS-F, which are associated with trichoid sensilla and co-expressed with the well-studied Drosophila pheromone binding protein LUSH. The results provide evidence of involvement of CcapOBP83a-2 in the medfly's odorant perception and its wider specificity for (E,E)-α-farnesene, one of the five major compounds in medfly male pheromone emission. This represents the first step in the clarification of the C. capitata and pheromone reception pathway, and a starting point for further studies aimed towards the creation of new powerful attractants or repellents applicable in the actual control strategies.
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Affiliation(s)
- P Siciliano
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom; Dipartimento di Biologia e Biotecnologie, Università di Pavia, Via Ferrata 9, 27100 Pavia, Italia
| | - X L He
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - C Woodcock
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - J A Pickett
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - L M Field
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - M A Birkett
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - B Kalinova
- Institute of Organic Chemistry and Biochemistry of the AS CR, v.v.i., Flemingovo nám. 2, CZ-166 10 Prague 6, Czech Republic
| | - L M Gomulski
- Dipartimento di Biologia e Biotecnologie, Università di Pavia, Via Ferrata 9, 27100 Pavia, Italia
| | - F Scolari
- Dipartimento di Biologia e Biotecnologie, Università di Pavia, Via Ferrata 9, 27100 Pavia, Italia
| | - G Gasperi
- Dipartimento di Biologia e Biotecnologie, Università di Pavia, Via Ferrata 9, 27100 Pavia, Italia
| | - A R Malacrida
- Dipartimento di Biologia e Biotecnologie, Università di Pavia, Via Ferrata 9, 27100 Pavia, Italia
| | - J J Zhou
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom.
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Abstract
Using computational methods, which allow mechanistic insights at a molecular level, we explored the olfactory receptor (OR)-odor interactions for 2 mouse ORs, S79 and S86. Both ORs have been previously experimentally, functionally characterized. The odors used were mostly carboxylic acids, which differed in chain length, substituents on the primary carbon atom-chain and degree of unsaturation. These odors elicited varied activation responses from both ORs. Our studies revealed that both receptors have 2 distinct binding sites. Preferential binding in 1 of the 2 sites is correlated with OR activation. The activating odorants: nonanedioic acid, heptanoic acid, and octanoic acid for OR S79 and nonanoic acid for OR S86 preferentially bind in the region bound by transmembranes (TMs [helical domains]) III, IV, V, and VI. The non excitatory odorants heptanol for S79 and heptanoic acid for S86 showed a greater likelihood of binding in the region bound by TMs I, II, III, and VII. Nanosecond-scale molecular dynamics simulations of the physiologically relevant conditions of docked OR-odorant complexes enabled us to quantitatively assess the roles of individual OR amino acids in odor binding. Amino acid-odorant contact maps and distance determinations over the course of the simulations lend support to our conclusions.
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Affiliation(s)
- Peter C Lai
- Department of Genetics, Division of Research, University of Alabama at Birmingham, 720 20th Street S., Birmingham, AL 35294, USA.
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Velez Z, Hubbard PC, Barata EN, Canário AVM. Olfactory transduction pathways in the Senegalese sole Solea senegalensis. J Fish Biol 2013; 83:501-514. [PMID: 23991870 DOI: 10.1111/jfb.12185] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 06/08/2013] [Indexed: 06/02/2023]
Abstract
This study tested whether differences in sensitivity between the upper and lower olfactory epithelia of Solea senegalensis are associated with different odorant receptors and transduction pathways, using the electro-olfactogram. Receptor mechanisms were assessed by cross-adaptation with amino acids (L-cysteine, L-phenylalanine and 1-methyl-L-tryptophan) and bile acids (taurocholic acid and cholic acid). This suggested that relatively specific receptors exist for 1-methyl-L-tryptophan and L-phenylalanine (food-related odorants) in the lower epithelium, and for taurocholic acid (conspecific-derived odorant) in the upper. Inhibition by U73122 [a phospholipase C (PLC) inhibitor] suggested that olfactory responses to amino acids were mediated mostly, but not entirely, by PLC-mediated transduction (IC50 ; 15-55 nM), whereas bile acid responses were mediated by both PLC and adenylate cyclase-cyclic adenosine monophosphate (AC-cAMP) (using SQ-22536; an AC inhibitor). Simultaneous application of both drugs rarely inhibited responses completely, suggesting possible involvement of non-PLC and non-AC mediated mechanisms. For aromatic amino acids and bile acids, there were differences in the contribution of each transduction pathway (PLC, AC and non-PLC and non-AC) between the two epithelia. These results suggest that differences in sensitivity of the two epithelia are associated with differences in odorant receptors and transduction mechanisms.
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Affiliation(s)
- Z Velez
- Centro de Ciências do Mar, Universidade do Algarve, Faro, Portugal.
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Abstract
One of the remarkable characteristics of higher organisms is the enormous assortment of cell types that emerge from a common genome. The immune system, with the daunting duty of detecting an astounding number of pathogens, and the nervous system with the equally bewildering task of perceiving and interpreting the external world, are the quintessence of cellular diversity. As we began to appreciate decades ago, achieving distinct expression programs among similar cell types cannot be accomplished solely by deterministic regulatory systems, but by the involvement of some type of stochasticity. In the last few years our understanding of these non-deterministic mechanisms is advancing, and this review will provide a brief summary of the current view of stochastic gene expression with focus on olfactory receptor (OR) gene choice, the epigenetic underpinnings of which recently began to emerge.
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Affiliation(s)
- Angeliki Magklara
- Department of Anatomy, University of California San Francisco, CA 94920, USA.
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Abstract
The mammalian odorant receptor (OR) repertoire is an attractive model to study evolution, because ORs have been subjected to rapid evolution between species, presumably caused by changes of the olfactory system to adapt to the environment. However, functional assessment of ORs in related species remains largely untested. Here we investigated the functional properties of primate and rodent ORs to determine how well evolutionary distance predicts functional characteristics. Using human and mouse ORs with previously identified ligands, we cloned 18 OR orthologs from chimpanzee and rhesus macaque and 17 mouse-rat orthologous pairs that are broadly representative of the OR repertoire. We functionally characterized the in vitro responses of ORs to a wide panel of odors and found similar ligand selectivity but dramatic differences in response magnitude. 87% of human-primate orthologs and 94% of mouse-rat orthologs showed differences in receptor potency (EC50) and/or efficacy (dynamic range) to an individual ligand. Notably dN/dS ratio, an indication of selective pressure during evolution, does not predict functional similarities between orthologs. Additionally, we found that orthologs responded to a common ligand 82% of the time, while human OR paralogs of the same subfamily responded to the common ligand only 33% of the time. Our results suggest that, while OR orthologs tend to show conserved ligand selectivity, their potency and/or efficacy dynamically change during evolution, even in closely related species. These functional changes in orthologs provide a platform for examining how the evolution of ORs can meet species-specific demands. The mammalian odorant receptor repertoire has been subjected to significant gene duplication and gene loss between species, presumably to adapt to the environment of an organism. However, even in distantly related species, a clear orthologous relationship exists for many genes. While ligands have been identified for several ORs, many of these receptors remain uncharacterized, especially in species other than human and mouse. Due to this paucity of functional data, it is assumed that ORs with similar sequence share functional characteristics. Here we investigate the functional evolution of OR orthologs—genes related via speciation—and OR paralogs—genes related via a duplication event—to provide insight as to how this large gene family has evolved. We show that OR orthologs have similar ligand selectivity to a panel of odors but differ in response magnitude. Additionally, orthologs respond to a common ligand more often than human OR paralogs, but there are vast differences in the potency and efficacy of individual receptors. This result stresses the broad importance of combining evolutionary genomics and molecular biology approaches to study gene function.
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Affiliation(s)
- Kaylin A. Adipietro
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Joel D. Mainland
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Neurobiology and Duke Institute for Brain Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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Scialò F, Hansson BS, Giordano E, Polito CL, Digilio FA. Molecular and functional characterization of the odorant receptor2 (OR2) in the tiger mosquito Aedes albopictus. PLoS One 2012; 7:e36538. [PMID: 22606270 PMCID: PMC3351472 DOI: 10.1371/journal.pone.0036538] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 04/09/2012] [Indexed: 12/04/2022] Open
Abstract
In mosquitoes, the olfactory system plays a crucial role in many types of behavior, including nectar feeding, host preference selection and oviposition. Aedes albopictus, known also as the tiger mosquito, is an anthropophilic species, which in the last few years, due to its strong ecological plasticity, has spread throughout the world. Although long considered only a secondary vector of viruses, the potential of its vector capacity may constitute a threat to public health. Based on the idea that an improved understanding of the olfactory system of mosquitoes may assist in the development of control methods that interfere with their behavior, we have undertaken a study aimed at characterizing the A. albopictus Odorant Receptors. Here we report the identification, cloning and functional characterization of the AalOR2 ortholog, that represents the first candidate member of the odorant receptor (OR) family of proteins from A. albopictus. AalOR2 is expressed in the larval heads and antennae of adults. Our data indicate that A. albopictus OR2 (AalOR2) shares a high degree of identity with other mosquito OR2 orthologs characterized to date, confirming that OR2 is one of the most conserved mosquito ORs. Our data indicate that AalOR2 is narrowly tuned to indole, and inhibited by (-)-menthone. In agreement with this results, these two compounds elicit two opposite effects on the olfactory-based behavior of A. albopictus larvae, as determined through a larval behavioral assay. In summary, this work has led to the cloning and de-orphaning of the first Odorant Receptor in the tiger mosquito A. albopictus. In future control strategies this receptor may be used as a potential molecular target.
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MESH Headings
- Aedes/genetics
- Aedes/physiology
- Amino Acid Sequence
- Animals
- Animals, Genetically Modified
- Base Sequence
- Behavior, Animal/drug effects
- Behavior, Animal/physiology
- Calcium/metabolism
- Cloning, Molecular
- Drosophila/genetics
- Drosophila/metabolism
- Female
- Gene Expression Profiling
- Genes, Insect
- HEK293 Cells
- Humans
- Indoles/pharmacology
- Insect Proteins/genetics
- Insect Proteins/physiology
- Larva/drug effects
- Larva/genetics
- Larva/metabolism
- Male
- Menthol/pharmacology
- Molecular Sequence Data
- Odorants
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Odorant/genetics
- Receptors, Odorant/physiology
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Sequence Homology, Amino Acid
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Affiliation(s)
- Filippo Scialò
- Institute of Genetics and Biophysics A. Buzzati-Traverso, CNR, Naples, Italy
| | - Bill S. Hansson
- Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology Jena, Germany
| | - Ennio Giordano
- Department of Biological Sciences, University of Naples Federico II, Naples, Italy
| | - Catello L. Polito
- Institute of Genetics and Biophysics A. Buzzati-Traverso, CNR, Naples, Italy
- Department of Biological Sciences, University of Naples Federico II, Naples, Italy
| | - F. Anna Digilio
- Institute of Genetics and Biophysics A. Buzzati-Traverso, CNR, Naples, Italy
- * E-mail:
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Jin HJ, Lee SH, Kim TH, Park J, Song HS, Park TH, Hong S. Nanovesicle-based bioelectronic nose platform mimicking human olfactory signal transduction. Biosens Bioelectron 2012; 35:335-341. [PMID: 22475887 DOI: 10.1016/j.bios.2012.03.012] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 03/06/2012] [Accepted: 03/09/2012] [Indexed: 11/18/2022]
Abstract
We developed a nanovesicle-based bioelectronic nose (NBN) that could recognize a specific odorant and mimic the receptor-mediated signal transmission of human olfactory systems. To build an NBN, we combined a single-walled carbon nanotube-based field effect transistor with cell-derived nanovesicles containing human olfactory receptors and calcium ion signal pathways. Importantly, the NBN took advantages of cell signal pathways for sensing signal amplification, enabling ≈ 100 times better sensitivity than that of previous bioelectronic noses based on only olfactory receptor protein and carbon nanotube transistors. The NBN sensors exhibited a human-like selectivity with single-carbon-atomic resolution and a high sensitivity of 1 fM detection limit. Moreover, this sensor platform could mimic a receptor-meditated cellular signal transmission in live cells. This sensor platform can be utilized for the study of molecular recognition and biological processes occurring at cell membranes and also for various practical applications such as food screening and medical diagnostics.
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Affiliation(s)
- Hye Jun Jin
- Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea
| | - Sang Hun Lee
- School of Chemical and Biological Engineering, Bio-MAX Institute, Seoul National University, Seoul 151-742, Republic of Korea
| | - Tae Hyun Kim
- Department of Chemistry, Soonchunhyang University, Asan 336-745, Republic of Korea
| | - Juhun Park
- Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea
| | - Hyun Seok Song
- School of Chemical and Biological Engineering, Bio-MAX Institute, Seoul National University, Seoul 151-742, Republic of Korea
| | - Tai Hyun Park
- School of Chemical and Biological Engineering, Bio-MAX Institute, Seoul National University, Seoul 151-742, Republic of Korea.
| | - Seunghun Hong
- Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea; Department of Biophysics and Chemical Biology, Seoul National University, Seoul 151-747, Republic of Korea.
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Sun YL, Huang LQ, Pelosi P, Wang CZ. Expression in antennae and reproductive organs suggests a dual role of an odorant-binding protein in two sibling Helicoverpa species. PLoS One 2012; 7:e30040. [PMID: 22291900 PMCID: PMC3264552 DOI: 10.1371/journal.pone.0030040] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 12/08/2011] [Indexed: 11/24/2022] Open
Abstract
Odorant-binding proteins (OBPs) mediate both perception and release of semiochemicals in insects. These proteins are the ideal targets for understanding the olfactory code of insects as well as for interfering with their communication system in order to control pest species. The two sibling Lepidopteran species Helicoverpa armigera and H. assulta are two major agricultural pests. As part of our aim to characterize the OBP repertoire of these two species, here we focus our attention on a member of this family, OBP10, particularly interesting for its expression pattern. The protein is specifically expressed in the antennae of both sexes, being absent from other sensory organs. However, it is highly abundant in seminal fluid, is transferred to females during mating and is eventually found on the surface of fertilised eggs. Among the several different volatile compounds present in reproductive organs, OBP10 binds 1-dodecene, a compound reported as an insect repellent. These results have been verified in both H. armigera and H. assulta with no apparent differences between the two species. The recombinant OBP10 binds, besides 1-dodecene, some linear alcohols and several aromatic compounds. The structural similarity of OBP10 with OBP1 of the mosquito Culex quinquefasciatus, a protein reported to bind an oviposition pheromone, and its affinity with 1-dodecene suggest that OBP10 could be a carrier for oviposition deterrents, favouring spreading of the eggs in these species where cannibalism is active among larvae.
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Affiliation(s)
- Ya-Lan Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ling-Qiao Huang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Paolo Pelosi
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Department of Biology of Crop Plants, University of Pisa, Pisa, Italy
| | - Chen-Zhu Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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Jones PL, Pask GM, Romaine IM, Taylor RW, Reid PR, Waterson AG, Sulikowski GA, Zwiebel LJ. Allosteric antagonism of insect odorant receptor ion channels. PLoS One 2012; 7:e30304. [PMID: 22272331 PMCID: PMC3260273 DOI: 10.1371/journal.pone.0030304] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 12/13/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND At a molecular level, insects utilize members of several highly divergent and unrelated families of cell-surface chemosensory receptors for detection of volatile odorants. Most odors are detected via a family of odorant receptors (ORs), which form heteromeric complexes consisting of a well-conserved OR co-receptor (Orco) ion channel and a non-conserved tuning OR that provides coding specificity to each complex. Orco functions as a non-selective cation channel and is expressed in the majority of olfactory receptor neurons (ORNs). As the destructive behaviors of many insects are principally driven by olfaction, Orco represents a novel target for behavior-based control strategies. While many natural and synthetic odorants have been shown to agonize Orco/Or complexes, only a single direct Orco modulator, VUAA1, has been described. In an effort to identify additional Orco modulators, we have investigated the structure/activity relationships around VUAA1. RESULTS A search of our compound library identified several VUAA1 analogs that were selected for evaluation against HEK cells expressing Orco from the malaria vector Anopheles gambiae (AgOrco). While the majority of compounds displayed no activity, many of these analogs possess no intrinsic efficacy, but instead, act as competitive VUAA1 antagonists. Using calcium mobilization assays, patch clamp electrophysiology, and single sensillum in vivo recording, we demonstrate that one such candidate, VU0183254, is a specific allosteric modulator of OR signaling, capable of broadly inhibiting odor-mediated OR complex activation. CONCLUSIONS We have described and characterized the first Orco antagonist, that is capable of non-competitively inhibiting odorant-evoked activation of OR complexes, thereby providing additional insight into the structure/function of this unique family of ligand-gated ion channels. While Orco antagonists are likely to have limited utility in insect control programs, they represent important pharmacological tools that will facilitate the investigation of the molecular mechanisms underlying insect olfactory signal transduction.
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Affiliation(s)
- Patrick L. Jones
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Gregory M. Pask
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Ian M. Romaine
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Robert W. Taylor
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Paul R. Reid
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Alex G. Waterson
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Gary A. Sulikowski
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Laurence J. Zwiebel
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Center for Molecular Neuroscience, Institute of Global Health and Program in Developmental Biology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- * E-mail:
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Peng H, Zhao LH. [Research progress on olfactory receptor]. Zhejiang Da Xue Xue Bao Yi Xue Ban 2012; 41:117-122. [PMID: 22419475 DOI: 10.3785/j.issn.1008-9292.2012.01.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The olfactory perception is the process that the olfactory receptor is activated by odorous molecules, which induce the transduction of signal in the cell and the chemical information is transduced into electrical impulses. After the changed signal is transmitted to the brain, the whole perception process completes. OR gene belongs to the multigene family. The coded olfactory receptor proteins belong to the G-protein-coupled receptor (GPCR) superfamily and therefore are invariably seven-transmembrane domain(7TM) protein. Olfactory receptor protein plays an important role in olfactory perception and signal transduction process.
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Affiliation(s)
- He Peng
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou 310058, China
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Glatz R, Bailey-Hill K. Mimicking nature's noses: from receptor deorphaning to olfactory biosensing. Prog Neurobiol 2010; 93:270-96. [PMID: 21130137 DOI: 10.1016/j.pneurobio.2010.11.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 11/09/2010] [Accepted: 11/22/2010] [Indexed: 12/21/2022]
Abstract
The way in which organisms detect specific volatile compounds within their environment, and the associated neural processing which produces perception and subsequent behavioural responses, have been of interest to scientists for decades. Initially, most olfaction research was conducted using electrophysiological techniques on whole animals. However, the discovery of genes encoding the family of human olfactory receptors (ORs) paved the way for the development of a range of cellular assays, primarily used to deorphan ORs from mammals and insects. These assays have greatly advanced our knowledge of the molecular basis of olfaction, however, while there is currently good agreement on vertebrate and nematode olfactory signalling cascades, debate still surrounds the signalling mechanisms in insects. The inherent specificity and sensitivity of ORs makes them prime candidates as biological detectors of volatile ligands within biosensor devices, which have many potential applications. In the previous decade, researchers have investigated various technologies for transducing OR:ligand interactions into a readable format and thereby produce an olfactory biosensor (or bioelectronic nose) that maintains the discriminating power of the ORs in vivo. Here we review and compare the molecular mechanisms of olfaction in vertebrates and invertebrates, and also summarise the assay technologies utilising sub-tissue level sensing elements (cells and cell extracts), which have been applied to OR deorphanization and biosensor research. Although there are currently no commercial, "field-ready" olfactory biosensors of the kind discussed here, there have been several technological proof-of-concept studies suggesting that we will see their emergence within the next decade.
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Affiliation(s)
- Richard Glatz
- South Australian Research and Development Institute (SARDI), Entomology, GPO Box 397, Adelaide 5001, Australia.
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