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Chang H, Unni AP, Tom MT, Cao Q, Liu Y, Wang G, Llorca LC, Brase S, Bucks S, Weniger K, Bisch-Knaden S, Hansson BS, Knaden M. Odorant detection in a locust exhibits unusually low redundancy. Curr Biol 2023; 33:5427-5438.e5. [PMID: 38070506 DOI: 10.1016/j.cub.2023.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/11/2023] [Accepted: 11/08/2023] [Indexed: 12/21/2023]
Abstract
Olfactory coding, from insects to humans, is canonically considered to involve considerable across-fiber coding already at the peripheral level, thereby allowing recognition of vast numbers of odor compounds. We show that the migratory locust has evolved an alternative strategy built on highly specific odorant receptors feeding into a complex primary processing center in the brain. By collecting odors from food and different life stages of the locust, we identified 205 ecologically relevant odorants, which we used to deorphanize 48 locust olfactory receptors via ectopic expression in Drosophila. Contrary to the often broadly tuned olfactory receptors of other insects, almost all locust receptors were found to be narrowly tuned to one or very few ligands. Knocking out a single receptor using CRISPR abolished physiological and behavioral responses to the corresponding ligand. We conclude that the locust olfactory system, with most olfactory receptors being narrowly tuned, differs from the so-far described olfactory systems.
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Affiliation(s)
- Hetan Chang
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Afairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Anjana P Unni
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Megha Treesa Tom
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Qian Cao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yang Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Guirong Wang
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Afairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Lucas Cortés Llorca
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Sabine Brase
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Sascha Bucks
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Kerstin Weniger
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Sonja Bisch-Knaden
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Bill S Hansson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany
| | - Markus Knaden
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans Knoell Strasse 8, 07745 Jena, Germany.
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Jaffar-Bandjee M, Figon F, Clémençon P, Renard JB, Casas J. Aerosol Alteration of Behavioral Response to Pheromone in Bombyx mori. J Chem Ecol 2023; 49:353-362. [PMID: 37120695 DOI: 10.1007/s10886-023-01431-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 04/13/2023] [Accepted: 04/16/2023] [Indexed: 05/01/2023]
Abstract
Because of the complexity to study them, aerosols have been neglected in nearly all studies on olfaction, especially studies dealing with odor capture. However, aerosols are present in large quantities in the atmosphere and have the physico-chemical ability to interact with odor molecules, in particular the many pheromones with low volatility. We submitted male moths of Bombyx mori to bombykol puffs, the main fatty alcohol component of its sex pheromone, depending on whether the air is free of aerosols, charged with ambient concentration aerosols or supplemented with aqueous aerosols and recorded their arousal behavior. Aerosols and pheromone do interact consistently over all experiments and moths react better in low aerosol-concentration conditions. We propose four hypotheses for explaining this impediment, the two most likely resorting to competition between odor molecules and aerosols for the olfactory pores and postulate a reversal to a positive impact of aerosols on communication, depending on the particular physico-chemical properties of the multiphasic interaction. Studying the partitioning between gas and particulate phases in the transport and reception of odors is key for advancing the chemico-physical understanding of olfaction.
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Affiliation(s)
- Mourad Jaffar-Bandjee
- Insect Biology Research Institute, University of Tours - CNRS, Tours, France.
- Biomaterials Department, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
| | - Florent Figon
- Insect Biology Research Institute, University of Tours - CNRS, Tours, France
- Laboratoire d'Ecologie Alpine, Univ. Grenoble-Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, Grenoble, France
| | - Paul Clémençon
- Insect Biology Research Institute, University of Tours - CNRS, Tours, France
| | - Jean-Baptiste Renard
- Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, CNRS - University of Orléans, Orléans, France
| | - Jérôme Casas
- Insect Biology Research Institute, University of Tours - CNRS, Tours, France
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Guo H, Gong XL, Li GC, Mo BT, Jiang NJ, Huang LQ, Wang CZ. Functional analysis of pheromone receptor repertoire in the fall armyworm, Spodoptera frugiperda. PEST MANAGEMENT SCIENCE 2022; 78:2052-2064. [PMID: 35124874 DOI: 10.1002/ps.6831] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 11/26/2021] [Accepted: 02/06/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND The fall armyworm, Spodoptera frugiperda (J. E. Smith), is a polyphagous moth species that is spreading all around the globe. It uses (Z)-9-tetradecenyl acetate (Z9-14:Ac) and (Z)-7-dodecenyl acetate (Z7-12:Ac) (100:3.9) as essential sex pheromone components. However, our understanding of the molecular basis of pheromone detection of S. frugiperda is still incomplete. RESULTS Herein, we identified six PRs, i.e. SfruOR6, 11, 13, 16, 56, and 62, by transcriptome sequencing. Subsequently, we heterologously expressed them in Drosophila OR67d neurons and determined their response spectra with a large panel of sex pheromones and analogs. Among them, SfruOR13-expressing neurons strongly respond to the major sex pheromone component Z9-14:Ac, but also comparably to (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:Ac) and weakly to (Z)-9-dodecenyl acetate (Z9-12:Ac). Both SfruOR56 and SfruOR62 are specifically tuned to the minor sex pheromone component Z7-12:Ac with varying intensities and sensitivities. In addition, SfruOR6 is activated only by Z9,E12-14:Ac, and SfruOR16 by both (Z)-9-tetradecenol (Z9-14:OH) and (Z)-9-tetradecenal (Z9-14:Ald). However, the OR67d neurons expressing SfruOR11 remain silent to all compounds tested, a phenomenon commonly found in the OR11 clade of Noctuidae species. Next, using single sensillum recording, we characterized four sensilla types on the antennae of males, namely A, B, C and D types that are tuned to the ligands of PRs, thereby confirming that S. frugiperda uses both SfruOR56 and SfruOR62 to detect Z7-12:Ac. Finally, using wind tunnel assay, we demonstrate that both Z9,E12-14:Ac and Z9-14:OH act as antagonists to the sex pheromone. CONCLUSION We have deorphanized five PRs and characterized four types of sensilla responsible for the detection of pheromone compounds, providing insights into the peripheral encoding of sex pheromones in S. frugiperda.
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Affiliation(s)
- Hao Guo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Xin-Lin Gong
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Guo-Cheng Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Bao-Tong Mo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Nan-Ji Jiang
- 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
| | - Chen-Zhu Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
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Al-Jalely BH, Wang P, Liao Y, Xu W. Identification and characterization of olfactory genes in the parasitoid wasp Diadegma semiclausum (Hellén) (Hymenoptera: Ichneumonidae). BULLETIN OF ENTOMOLOGICAL RESEARCH 2022; 112:187-196. [PMID: 34474703 DOI: 10.1017/s0007485321000675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Diadegma semiclausum is an important parasitoid wasp and widely used in the biological control of the diamondback moth, Plutella xylostella, one of the most destructive pests of cruciferous plants. Insect olfactory system is critical in guiding behaviors including feeding, mating, and oviposition, in which odorant binding proteins (OBPs) and odorant receptors (ORs) are two key components. However, limited attention has been paid to D. semiclausum olfactory genes. In this study, a transcriptome sequencing was performed on the RNA samples extracted from D. semiclausum male and female adult antennae. A total of 17 putative OBP and 67 OR genes were annotated and further compared to OBPs and ORs from P. xylostella, and other hemipteran parasitoid species. The expression patterns of D. semiclausum OBPs between male and female antennae were examined using reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time PCR. Six OBPs (DsemOBP 6, 7, 8, 9, 10, and 14) demonstrated significantly higher expression levels in females than in males, which may assist in female D. semiclausum host-seeking and oviposition behaviors. This study advances our understanding of the olfactory system of D. semiclausum at the molecular level and paves the way for future functional studies aiming at increasing the efficacy to control P. xylostella by using D. semiclausum.
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Affiliation(s)
- Basman H Al-Jalely
- Food Futures Institute, Murdoch University, Perth, WA6150, Australia
- College of Agricultural Engineering Sciences, University of Baghdad, Baghdad, Iraq
| | - Penghao Wang
- Food Futures Institute, Murdoch University, Perth, WA6150, Australia
| | - Yalin Liao
- Food Futures Institute, Murdoch University, Perth, WA6150, Australia
| | - Wei Xu
- Food Futures Institute, Murdoch University, Perth, WA6150, Australia
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Sims C, Withall DM, Oldham N, Stockman R, Birkett M. Computational investigation of aphid odorant receptor structure and binding function. J Biomol Struct Dyn 2022; 41:3647-3658. [PMID: 35352606 DOI: 10.1080/07391102.2022.2053743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Odorant receptors (OR) play a critical role in signal transduction and olfactory recognition in insects. Unfortunately, insect ORs are difficult to express and purify, and limited structural data are available. Computational methods were used to predict models for aphid ORs, and binding interactions with aphid pheromones and other semiochemicals were investigated. Previously functionally characterised ORs from the pea aphid, Acyrthosiphon pisum, ApisOR4 and ApisOR5, were screened against functional ligands. ApisOR5 had a defined binding site, and had predicted interactions with the aphid alarm pheromone, (E)-β-farnesene. ApisOR4 had multiple distinct binding sites and showed broad tuning to multiple odorants. Screening of six other highly conserved ORs showed some interactions and potential enantiomeric discrimination between the aphid sex pheromone components (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol. These results indicate that specific binding sites may be more critical to understanding olfactory activity of ligands and ORs than kinetic data, and greater knowledge of the method of action of ORs is required.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Cassie Sims
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, UK.,School of Chemistry, University of Nottingham, Nottingham, UK
| | - David M Withall
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, UK
| | - Neil Oldham
- School of Chemistry, University of Nottingham, Nottingham, UK
| | - Robert Stockman
- School of Chemistry, University of Nottingham, Nottingham, UK
| | - Michael Birkett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, UK
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Guo H, Huang LQ, Gong XL, Wang CZ. Comparison of functions of pheromone receptor repertoires in Helicoverpa armigera and Helicoverpa assulta using a Drosophila expression system. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 141:103702. [PMID: 34942332 DOI: 10.1016/j.ibmb.2021.103702] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 12/07/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Helicoverpa armigera and H. assulta are sympatric closely related species sharing two sex pheromone components, (Z)-11-hexadecenal (Z11-16:Ald) and (Z)-9-hexadecenal (Z9-16:Ald) but in opposite ratios, 97:3 and 3:97 respectively. This feature makes them a feasible model for studying the evolution of pheromone coding mechanisms of lepidopteran insects. Despite a decade-long study to deorphanize the pheromone receptor (PR) repertoires of the two species, the comparison of the function of all PR orthologs between the two species is incomplete. Moreover, the ligands of OR14 and OR15 have so far not been found, likely due to the missing of the active ligand(s) in the compound panel and/or incompatibility of heterologous expression systems used. In the present study, we expressed the PR repertoires of both Helicoverpa species in Drosophila T1 neurons to comparatively study the function of PRs. Among those PRs, OR13, OR6, and OR14 of both species are functionally conserved and narrowly tuned, and the T1 neurons expressing each of them respond to Z11-16:Ald, (Z)-9-hexadecenol (Z9-16:OH), and (Z)-11-hexadecenyl acetate (Z11-16:Ac), respectively. While HarmOR16-expressing neurons respond strongly to (Z)-9-tetradecenal (Z9-14:Ald) and (Z)-11-hexadecenol (Z11-16:OH), the neurons expressing HassOR16 mainly respond to Z9-14:Ald and also weakly respond to (Z)-9-tetradecenol (Z9-14:OH). Moreover, HarmOR14b-expressing neurons are activated by Z9-14:Ald, whereas HassOR14b-expressing neurons are sensitive to Z9-16:Ald, Z9-14:Ald, and (Z)-9-hexadecenol (Z9-16:OH). In addition, HarmOR15-expressing neurons are selectively responsive to Z9-14:Ald. However, the Drosophila T1 neurons expressing either HarmOR11 or HassOR11 are silent to all of the compounds tested. In summary, except for OR11, we have deorphanized all the PRs of these two Helicoverpa species using a Drosophila expression system and a large panel of pheromone compounds, thereby providing a valuable reference for parsing the code of peripheral coding of pheromones.
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Affiliation(s)
- Hao Guo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Ling-Qiao Huang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Xin-Lin Gong
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Chen-Zhu Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, PR China.
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Le A, Wu Y, Liu W, Wu C, Hu P, Zou J, Kuang L. MiR-144-induced KLF2 inhibition and NF-kappaB/CXCR1 activation promote neutrophil extracellular trap-induced transfusion-related acute lung injury. J Cell Mol Med 2021; 25:6511-6523. [PMID: 34120407 PMCID: PMC8278117 DOI: 10.1111/jcmm.16650] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 04/01/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022] Open
Abstract
Transfusion‐related acute lung injury (TRALI) is a clinical syndrome which is associated with the formation of neutrophil extracellular trap (NET). Recent studies have demonstrated the roles of microRNAs (miRNAs) in the pathophysiological process of TRALI. Here, the study focused on the role of miR‐144 and the molecular mechanisms in NET‐induced TRALI. Up‐regulated miR‐144 and under‐expressed KLF2 were determined in patients with TRALI. In the mouse model of a two‐event TRALI induced by intraperitoneal injections with lipopolysaccharide and anti‐H‐2Kd mAb, we determined expression patterns of miR‐144, Krüppel‐like factor 2 (KLF2), chemokine (C‐X‐C motif) receptor 1 (CXCR1) and nuclear factor kappa‐B (NF‐kappaB) p65. The results confirmed that miR‐144 was highly expressed, while KLF2 was poorly expressed in mice with TRALI. Dual‐luciferase reporter gene assay identified that miR‐144 could target KLF2. Using gain‐ and loss‐of‐function approaches, we analysed the effects of miR‐144 and its interaction with KLF2 on TRALI. Enforced expression of miR‐144 was found to aggravate NET‐induced TRALI by down‐regulating KLF2 and activating the NF‐kappaB/CXCR1 signalling pathway in TRALI mice. Collectively, miR‐144‐targeted inhibition of KLF2 and activation of NF‐kappaB/CXCR1 are possible mechanisms responsible for NET‐caused TRALI. These findings aid in the development of therapeutic modalities for the treatment of TRALI.
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Affiliation(s)
- Aiping Le
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yize Wu
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Wei Liu
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Chenggao Wu
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Piaoping Hu
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Juan Zou
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Linju Kuang
- Departments of Blood Transfusion, The First Affiliated Hospital of Nanchang University, Nanchang, China
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Guo H, Guo PP, Sun YL, Huang LQ, Wang CZ. Contribution of odorant binding proteins to olfactory detection of (Z)-11-hexadecenal in Helicoverpa armigera. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2021; 131:103554. [PMID: 33600999 DOI: 10.1016/j.ibmb.2021.103554] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 02/04/2021] [Accepted: 02/09/2021] [Indexed: 05/14/2023]
Abstract
Helicoverpa armigera utilizes (Z)-11-hexadecenal (Z11-16:Ald) as its major sex pheromone component. Three pheromone binding proteins (PBPs) and two general odorant binding proteins (GOBPs) are abundantly expressed in the male antennae of H. armigera. However, their precise roles in the olfactory detection of Z11-16:Ald remain enigmatic. To answer this question, we first synthesized the antibody against HarmOR13, an olfactory receptor (OR) primarily responding to Z11-16:Ald and mapped the local associations between PBPs/GOBPs and HarmOR13. Immunostaining showed that HarmPBPs and HarmGOBPs were localized in the supporting cells of trichoid sensilla and basiconic sensilla respectively. In particular, HarmPBP1 and HarmPBP2 were colocalized in the cells surrounding the olfactory receptor neurons (ORNs) expressing HarmOR13. Next, using two noninterfering binary expression tools, we heterologously expressed HarmPBP1, HarmPBP2 and HarmOR13 in Drosophila T1 sensilla to validate the functional interplay between PBPs and HarmOR13. We found that the addition of HarmPBP1 or HarmPBP2, not HarmPBP3, significantly increased HarmOR13's response to Z11-16:Ald. However, the presence of either HarmPBP1 or HarmPBP2 was ineffective to change the tuning breadth of HarmOR13 and modulate the response kinetics of this receptor. Taken together, this work demonstrates both HarmPBP1 and HarmPBP2 are involved in Z11-16:Ald detection. Our results support the idea that PBPs can contribute to the peripheral olfactory sensitivity but do little in modulating the selectivity and the response kinetics of corresponding ORs.
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Affiliation(s)
- Hao Guo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, PR China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, PR China
| | - Ping-Ping Guo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, PR China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, PR China
| | - Ya-Lan Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, PR China; Forest College, Henan University of Science and Technology, Luoyang, PR China
| | - Ling-Qiao Huang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, PR China
| | - Chen-Zhu Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, PR China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, PR China.
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Xin S, Zhang W. Construction and analysis of the protein-protein interaction network for the olfactory system of the silkworm Bombyx mori. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2020; 105:e21737. [PMID: 32926465 DOI: 10.1002/arch.21737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
Olfaction plays an essential role in feeding and information exchange in insects. Previous studies on the olfaction of silkworms have provided a wealth of information about genes and proteins, yet, most studies have only focused on a single gene or protein related to the insect's olfaction. The aim of the current study is to determine key proteins in the olfactory system of the silkworm, and further understand protein-protein interactions (PPIs) in the olfactory system of Lepidoptera. To achieve this goal, we integrated Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and network analyses. Furthermore, we selected 585 olfactory-related proteins and constructed a (PPI) network for the olfactory system of the silkworm. Network analysis led to the identification of several key proteins, including GSTz1, LOC733095, BGIBMGA002169-TA, BGIBMGA010939-TA, GSTs2, GSTd2, Or-2, and BGIBMGA013255-TA. A comprehensive evaluation of the proteins showed that glutathione S-transferases (GSTs) had the highest ranking. GSTs also had the highest enrichment levels in GO and KEGG. In conclusion, our analysis showed that key nodes in the biological network had a significant impact on the network, and the key proteins identified via network analysis could serve as new research targets to determine their functions in olfaction.
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Affiliation(s)
- Shanghong Xin
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Wenjun Zhang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
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10
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False positives from impurities result in incorrect functional characterization of receptors in chemosensory studies. Prog Neurobiol 2019; 181:101661. [DOI: 10.1016/j.pneurobio.2019.101661] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/24/2019] [Accepted: 07/06/2019] [Indexed: 12/11/2022]
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11
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Zhang L, Guo M, Zhuo F, Xu H, Zheng N, Zhang L. An odorant-binding protein mediates sexually dimorphic behaviors via binding male-specific 2-heptanone in migratory locust. JOURNAL OF INSECT PHYSIOLOGY 2019; 118:103933. [PMID: 31449797 DOI: 10.1016/j.jinsphys.2019.103933] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/28/2019] [Accepted: 08/22/2019] [Indexed: 06/10/2023]
Abstract
Migratory locusts (Locusta migratoria) frequently aggregate into huge swarms that cause serious economic losses for the agricultural sector. Differential behaviors of male and female insects may contribute to such population explosions. However, the key olfactory mechanisms underlying different behaviors associated with sex-related pheromones are unclear. Here, we report that male-specific odor, 2-heptanone plays different roles in relation to the behavior of migratory locust males and females, and that this sexual dimorphism involves a soluble odorant-binding protein (OBP) in the peripheral olfactory processes. This odor strongly binds to LmigOBP4, a novel OBP, present in antennal trichoid sensilla, and elicits opposite locomotor tendencies between the sexes: attracting females and repelling males. Furthermore, an adult male group mimicked a high dosage of 2-heptanone by promoting their attractiveness to single females. Additionally, RNAi suppression of Lmigobp4 expression reduced the physiological responses to 2-heptanone to levels that were indistinguishable between the sexes. This suppression reversed the adult behavioral responses to 2-heptanone, i.e., females were repelled and males were attracted. We conclude that LmigOBP4 is associated with olfactory recognition of male-specific 2-heptanone, which plays dual roles that differ between adult male and female migratory locusts.
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Affiliation(s)
- Liwei Zhang
- Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China
| | - Mei Guo
- Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China
| | - Fuyan Zhuo
- Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China
| | - Haozhi Xu
- Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China
| | - Nan Zheng
- Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China
| | - Long Zhang
- Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China.
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12
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Tang QF, Shen C, Zhang Y, Yang ZP, Han RR, Wang J. Antennal transcriptome analysis of the maize weevil Sitophilus zeamais: Identification and tissue expression profiling of candidate odorant-binding protein genes. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2019; 101:e21542. [PMID: 30820994 DOI: 10.1002/arch.21542] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 01/14/2019] [Accepted: 02/05/2019] [Indexed: 06/09/2023]
Abstract
Our bioassays reviewed that antennae played crucial roles in the responses of maize weevil (Sitophilus zeamais) to food and sex volatiles. In order to identify the maize weevil odorant-binding protein (OBP) genes, we analyzed its antennal transcriptome. In total, 21,587,928 high-quality clean reads were obtained from RNA-seq, 52,206 unigenes were assembled, and 25,744 unigenes showed significant similarity ( E value < 10 -5 ) to known proteins in the NCBI nonredundant protein database. From those unigenes, we identified 41 candidate OBP proteins, which could be categorized into dimeric OBPs subfamily, minus-C OBPs subfamily, and classical OBPs subfamily. Phylogenic analysis indicated that most maize weevil OBPs were closely related to their orthologues in other beetles of the Superfamily Curculionoidea. We further investigated the expression profiles of those candidate OBP genes by quantitative real-time polymerase chain reaction. Twenty-six of forty-one maize weevil OBP genes were highly expressed in the antennae or other parts of the head. The rest were expressed in the legs, wings, or other tested tissues. The antennal transcriptomic data and candidate OBP genes described here provide a basis for the functional studies of the maize weevil chemical perception, which are potential novel targets for pest control strategies.
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Affiliation(s)
- Qing-Feng Tang
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, China
| | - Chen Shen
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, China
| | - Ying Zhang
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, China
| | - Zhi-Peng Yang
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, China
| | - Rong-Rong Han
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, China
| | - Jian Wang
- Department of Entomology, University of Maryland, College Park, Maryland
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13
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Fleischer J, Krieger J. Insect Pheromone Receptors - Key Elements in Sensing Intraspecific Chemical Signals. Front Cell Neurosci 2018; 12:425. [PMID: 30515079 PMCID: PMC6255830 DOI: 10.3389/fncel.2018.00425] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 10/30/2018] [Indexed: 12/20/2022] Open
Abstract
Pheromones are chemicals that serve intraspecific communication. In animals, the ability to detect and discriminate pheromones in a complex chemical environment substantially contributes to the survival of the species. Insects widely use pheromones to attract mating partners, to alarm conspecifics or to mark paths to rich food sources. The various functional roles of pheromones for insects are reflected by the chemical diversity of pheromonal compounds. The precise detection of the relevant intraspecific signals is accomplished by specialized chemosensory neurons housed in hair-like sensilla located on the surface of body appendages. Current data indicate that the extraordinary sensitivity and selectivity of the pheromone-responsive neurons (PRNs) is largely based on specific pheromone receptors (PRs) residing in their ciliary membrane. Besides these key elements, proper ligand-induced responses of PR-expressing neurons appear to generally require a putative co-receptor, the so-called "sensory neuron membrane protein 1" (SNMP1). Regarding the PR-mediated chemo-electrical signal transduction processes in insect PRNs, ionotropic as well as metabotropic mechanisms may be involved. In this review, we summarize and discuss current knowledge on the peripheral detection of pheromones in the olfactory system of insects with a focus on PRs and their specific role in the recognition and transduction of volatile intraspecific chemical signals.
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Affiliation(s)
- Jörg Fleischer
- Department of Animal Physiology, Institute of Biology/Zoology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Jürgen Krieger
- Department of Animal Physiology, Institute of Biology/Zoology, Martin Luther University Halle-Wittenberg, Halle, Germany
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14
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Wang B, Liu Y, Wang GR. Proceeding From in vivo Functions of Pheromone Receptors: Peripheral-Coding Perception of Pheromones From Three Closely Related Species, Helicoverpa armigera, H. assulta, and Heliothis virescens. Front Physiol 2018; 9:1188. [PMID: 30214413 PMCID: PMC6125646 DOI: 10.3389/fphys.2018.01188] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/07/2018] [Indexed: 01/07/2023] Open
Abstract
Three closely related species, Helicoverpa armigera, H. assulta, and Heliothis virescens from Lepidoptera Noctuidae, are used as a model system for exploring sexual communication and species isolation. Pheromone receptors (PRs) previously discovered in model moth species include seven in H. armigera, six in H. assulta, and six in H. virescens. PRs named OR6, OR13, and OR16 among these species were found to be functional, characterized by an in vitro Xenopus oocytes system. Using an in vivo transgenic fly system, functional assays of OR6, OR13, and OR16 clades from three closely related Noctuidae species showed that OR13 function was highly conserved, whereas OR6 and OR16 exhibited functional divergence. Similar results were produced from assays in the Xenopus oocytes system. Combined with earlier behavioral results and electrophysiological recordings, we found corresponding relationships among pheromones, PRs, and neurons at the periphery sensory system of each species. Our results provide vital information at the neuronal and molecular level, shedding insight into the sexual communication of closely related species in Lepidoptera.
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Affiliation(s)
- Bing Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yang Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Gui-Rong Wang
- 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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15
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Ma L, Li Z, Zhang W, Cai X, Luo Z, Zhang Y, Chen Z. The Odorant Binding Protein 6 Expressed in Sensilla Chaetica Displays Preferential Binding Affinity to Host Plants Volatiles in Ectropis obliqua. Front Physiol 2018; 9:534. [PMID: 29867573 PMCID: PMC5967201 DOI: 10.3389/fphys.2018.00534] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 04/24/2018] [Indexed: 11/16/2022] Open
Abstract
The monophagous tea geometrid Ectropis obliqua selectively feed on tea plants, requiring the specialized chemosensory system to forage for certain host. A deep insight into the molecular basis would accelerate the design of insect-behavior-modifying stimuli. In the present study, we focused on the odorant-binding protein 6 (EoblOBP6) with the high abundance in legs transcriptome of E. obliqua moths. qRT-PCR coupled with western blot analyses revealed the dual expression pattern of EoblOBP6 in antennae and legs. Cellular immunolocalization indicated that EoblOBP6 was predominantly labeled in the outer sensillum lymph of uniporous sensilla chaetica, which is not innervated by sensory neurons. No specific staining was observed in other sensillum types. The fluorescence competition assay showed a relatively narrow binding spectrum of recombinant EoblOBP6. EoblOBP6 could not only bind with intact tea plant volatiles benzaldehyde but also display high binding ability to nerolidol and α-farnesene which are tea plant volatiles dramatically induced by herbivore infestation. Besides, EoblOBP6 tightly bound to the aversive bitter alkaloid berberine. Taken together, EoblOBP6 displayed an unusual expression in sensilla chaetica, exhibited the potential involvement in olfaction and gustation, and may play a functional role in host location of female E. obliqua moths.
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Affiliation(s)
- Long Ma
- Jiangxi Key Laboratory of Bioprocess Engineering, College of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang, China
| | - Zhaoqun Li
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Wanna Zhang
- Institute of Entomology, Jiangxi Agricultural University, Nanchang, China
| | - Xiaoming Cai
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Zongxiu Luo
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Yongjun Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zongmao Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
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16
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de Fouchier A, Walker WB, Montagné N, Steiner C, Binyameen M, Schlyter F, Chertemps T, Maria A, François MC, Monsempes C, Anderson P, Hansson BS, Larsson MC, Jacquin-Joly E. Functional evolution of Lepidoptera olfactory receptors revealed by deorphanization of a moth repertoire. Nat Commun 2017; 8:15709. [PMID: 28580965 PMCID: PMC5465368 DOI: 10.1038/ncomms15709] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 04/20/2017] [Indexed: 02/07/2023] Open
Abstract
Insects detect their hosts or mates primarily through olfaction, and olfactory receptors (ORs) are at the core of odorant detection. Each species has evolved a unique repertoire of ORs whose functional properties are expected to meet its ecological needs, though little is known about the molecular basis of olfaction outside Diptera. Here we report a pioneer functional analysis of a large array of ORs in a lepidopteran, the herbivorous pest Spodoptera littoralis. We demonstrate that most ORs are narrowly tuned to ubiquitous plant volatiles at low, relevant odorant titres. Our phylogenetic analysis highlights a basic conservation of function within the receptor repertoire of Lepidoptera, across the expansive evolutionary radiation of different major clades. Our study provides a reference for further studies of olfactory mechanisms in Lepidoptera, a historically crucial insect order in olfactory research.
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Affiliation(s)
- Arthur de Fouchier
- INRA, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, Route de Saint-Cyr, 78026 Versailles Cedex, France
| | - William B. Walker
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sundsvägen 14, 230 53 Alnarp, Sweden
| | - Nicolas Montagné
- Sorbonne Universités—UPMC University Paris 06, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, 7 quai Saint Bernard, 75252 Paris Cedex 05, France
| | - Claudia Steiner
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sundsvägen 14, 230 53 Alnarp, Sweden
- Sorbonne Universités—UPMC University Paris 06, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, 7 quai Saint Bernard, 75252 Paris Cedex 05, France
| | - Muhammad Binyameen
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sundsvägen 14, 230 53 Alnarp, Sweden
- Chemical Ecology Laboratory, Department of Entomology, Bahauddin Zakariya University, Multan 60800, Pakistan
| | - Fredrik Schlyter
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sundsvägen 14, 230 53 Alnarp, Sweden
| | - Thomas Chertemps
- Sorbonne Universités—UPMC University Paris 06, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, 7 quai Saint Bernard, 75252 Paris Cedex 05, France
| | - Annick Maria
- Sorbonne Universités—UPMC University Paris 06, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, 7 quai Saint Bernard, 75252 Paris Cedex 05, France
| | - Marie-Christine François
- INRA, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, Route de Saint-Cyr, 78026 Versailles Cedex, France
| | - Christelle Monsempes
- INRA, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, Route de Saint-Cyr, 78026 Versailles Cedex, France
| | - Peter Anderson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sundsvägen 14, 230 53 Alnarp, Sweden
| | - Bill S. Hansson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Mattias C. Larsson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sundsvägen 14, 230 53 Alnarp, Sweden
| | - Emmanuelle Jacquin-Joly
- INRA, Institute of Ecology & Environmental Sciences of Paris, Department of Sensory Ecology, Route de Saint-Cyr, 78026 Versailles Cedex, France
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17
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Brito NF, Moreira MF, Melo ACA. A look inside odorant-binding proteins in insect chemoreception. JOURNAL OF INSECT PHYSIOLOGY 2016; 95:51-65. [PMID: 27639942 DOI: 10.1016/j.jinsphys.2016.09.008] [Citation(s) in RCA: 190] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 05/14/2023]
Abstract
Detection of chemical signals from the environment through olfaction is an indispensable mechanism for maintaining an insect's life, evoking critical behavioral responses. Among several proteins involved in the olfactory perception process, the odorant binding protein (OBP) has been shown to be essential for a normally functioning olfactory system. This paper discusses the role of OBPs in insect chemoreception. Here, structural aspects, mechanisms of action and binding affinity of such proteins are reviewed, as well as their promising application as molecular targets for the development of new strategies for insect population management and other technological purposes.
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Affiliation(s)
- Nathália F Brito
- Universidade Federal do Rio de Janeiro, Instituto de Química, 21941-909 Rio de Janeiro, RJ, Brazil
| | - Monica F Moreira
- Universidade Federal do Rio de Janeiro, Instituto de Química, 21941-909 Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil
| | - Ana C A Melo
- Universidade Federal do Rio de Janeiro, Instituto de Química, 21941-909 Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil.
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18
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You Y, Smith DP, Lv M, Zhang L. A broadly tuned odorant receptor in neurons of trichoid sensilla in locust, Locusta migratoria. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 79:66-72. [PMID: 27815144 PMCID: PMC5697761 DOI: 10.1016/j.ibmb.2016.10.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 10/21/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. Odorant receptors (ORs) on the membrane of chemosensory neurons are believed to be key molecules in sensing exogenous chemical cues. ORs in different species of insects are diverse and should tune a species to its own specific semiochemicals relevant to their survival. The orthopteran insect, locust (Locusta migratoria), is a model hemimetabolous insect. There is very limited knowledge on the functions of locust ORs although many locust OR genes have been identified in genomic sequencing experiments. In this paper, a locust OR, LmigOR3 was localized to neurons housed in trichoid sensilla by in situ hybridization. LmigOR3 was expressed as a transgene in Drosophila trichoid olfactory neurons (aT1) lacking the endogenous receptor Or67d and the olfactory tuning curve and dose-response curves were established for this locust receptor. The results show that LmigOR3 sensitizes neurons to ketones, esters and heterocyclic compounds, indicating that LmigOR3 is a broadly tuned receptor. LmigOR3 is the first odorant receptor from Orthoptera that has been functionally analyzed in the Drosophila aT1 system. This work demonstrates the utility of the Drosophila aT1 system for functional analysis of locust odorant receptors and suggests that LmigOR3 may be involved in detecting food odorants, or perhaps locust body volatiles that may help us to develop new control methods for locusts.
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Affiliation(s)
- Yinwei You
- Department of Entomology, China Agricultural University, Beijing 100193, PR China; Bio-tech Research Center, Shandong Academy of Agricultural Sciences, Jinan 250100, PR China.
| | - Dean P Smith
- Departments of Pharmacology and Neuroscience, University of Texas, Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Mingyue Lv
- Department of Entomology, China Agricultural University, Beijing 100193, PR China.
| | - Long Zhang
- Department of Entomology, China Agricultural University, Beijing 100193, PR China.
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19
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Wang B, Liu Y, He K, Wang G. Comparison of research methods for functional characterization of insect olfactory receptors. Sci Rep 2016; 6:32806. [PMID: 27633402 PMCID: PMC5025650 DOI: 10.1038/srep32806] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 08/10/2016] [Indexed: 12/11/2022] Open
Abstract
Insect olfactory receptors (ORs) in the peripheral olfactory system play an important role detecting elements of information from the environment. At present, various approaches are used for deorphanizing of ORs in insect. In this study, we compared methods for functional analysis of ORs in vitro and in vivo taking the candidate pheromone receptor OR13 of Helicoverpa assulta (HassOR13) as the object of our experiments. We found that the natural system was more sensitive than those utilizing transgenic Drosophila. The two-electrode voltage-clamp recording is more suitable for functional screening of large numbers of ORs, while the in vivo transgenic Drosophila system could prove more accurate to further validate the function of a specific OR. We also found that, among the different solvents used to dissolve pheromones and odorants, hexane offered good reproducibility and high sensitivity. Finally, the function of ORs was indirectly confirmed in transgenic Drosophila, showing that odor-activation of ORs-expressing olfactory receptor neurons (ORNs) can mediate behavioral choices. In summary, our results compare advantages and drawbacks of different approaches, thus helping in the choice of the method most suitable, in each specific situation, for deorphanizing insect ORs.
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Affiliation(s)
- Bing Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yang Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kang He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Guirong Wang
- 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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20
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Gonzalez F, Witzgall P, Walker WB. Protocol for Heterologous Expression of Insect Odourant Receptors in Drosophila. Front Ecol Evol 2016. [DOI: 10.3389/fevo.2016.00024] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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21
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Zhang DD, Löfstedt C. Moth pheromone receptors: gene sequences, function, and evolution. Front Ecol Evol 2015. [DOI: 10.3389/fevo.2015.00105] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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22
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de Fouchier A, Sun X, Monsempes C, Mirabeau O, Jacquin-Joly E, Montagné N. Evolution of two receptors detecting the same pheromone compound in crop pest moths of the genus Spodoptera. Front Ecol Evol 2015. [DOI: 10.3389/fevo.2015.00095] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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23
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Corcoran JA, Jordan MD, Thrimawithana AH, Crowhurst RN, Newcomb RD. The Peripheral Olfactory Repertoire of the Lightbrown Apple Moth, Epiphyas postvittana. PLoS One 2015; 10:e0128596. [PMID: 26017144 PMCID: PMC4446339 DOI: 10.1371/journal.pone.0128596] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 04/28/2015] [Indexed: 01/10/2023] Open
Abstract
The lightbrown apple moth, Epiphyas postvittana is an increasingly global pest of horticultural crops. Like other moths, E. postvittana relies on olfactory cues to locate mates and oviposition sites. To detect these cues, moths have evolved families of genes encoding elements of the peripheral olfactory reception system, including odor carriers, receptors and degrading enzymes. Here we undertake a transcriptomic approach to identify members of these families expressed in the adult antennae of E. postvittana, describing open reading frames encoding 34 odorant binding proteins, 13 chemosensory proteins, 70 odorant receptors, 19 ionotropic receptors, nine gustatory receptors, two sensory neuron membrane proteins, 27 carboxylesterases, 20 glutathione-S-transferases, 49 cytochrome p450s and 18 takeout proteins. For the odorant receptors, quantitative RT-PCR corroborated RNAseq count data on steady state transcript levels. Of the eight odorant receptors that group phylogenetically with pheromone receptors from other moths, two displayed significant male-biased expression patterns, one displayed significant female-biased expression pattern and five were expressed equally in the antennae of both sexes. In addition, we found two male-biased odorant receptors that did not group with previously described pheromone receptors. This suite of olfaction-related genes provides a substantial resource for the functional characterization of this signal transduction system and the development of odor-mediated control strategies for horticultural pests.
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Affiliation(s)
- Jacob A. Corcoran
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Melissa D. Jordan
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | | | - Ross N. Crowhurst
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Richard D. Newcomb
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
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24
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Feng B, Lin X, Zheng K, Qian K, Chang Y, Du Y. Transcriptome and expression profiling analysis link patterns of gene expression to antennal responses in Spodoptera litura. BMC Genomics 2015; 16:269. [PMID: 25887537 PMCID: PMC4502548 DOI: 10.1186/s12864-015-1375-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/21/2015] [Indexed: 11/30/2022] Open
Abstract
Background The study of olfaction is key to understanding the interaction of
insects with their environment and provides opportunities to develop novel
tactics for control of pest species. Recent developments in transcriptomic
approaches enable the molecular basis of olfaction to be studied even in species
with limited genomic information. Here we use transcriptome and expression
profiling analysis to characterize the antennal transcriptome of the noctuid
moth and polyphagous pest Spodoptera
litura. Results We identify 74 candidate genes involved in odor detection and
recognition, encoding 26 ORs, 21 OBPs, 18 CSPs and 9 IRs. We examine their
expression levels in both sexes and seek evidence for their function by relating
their expression with levels of EAG response in male and female antennae to 58
host and non-host plant volatiles and sex pheromone components. The majority of
olfactory genes showed sex-biased expression, usually male-biased in ORs. A link
between OR gene expression and antennal responses to odors was evident, a third
of the compounds tested evoking a sex-biased response, in every case also
male-biased. Two candidate pheromone receptors, OR14 and OR23 were especially
strongly expressed and male-biased and we suggest that these may respond to the
two female sex pheromone components of S.
litura, Z9E11-14:OAc and Z9E12-14:OAc, which evoked strongly
male-biased EAG responses. Conclusions Our results provide the molecular basis for elucidating the
olfactory profile of moths and the sexual divergence of their behavior and could
enable the targeting of particular genes, and behaviors for pest
management. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1375-x) contains supplementary material, which is available to authorized
users.
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Affiliation(s)
- Bo Feng
- Institute of Health and Environmental Ecology, Wenzhou Medical University, University Town, Wenzhou, 325035, China.
| | - Xinda Lin
- College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang, 310018, China.
| | - Kaidi Zheng
- Institute of Health and Environmental Ecology, Wenzhou Medical University, University Town, Wenzhou, 325035, China.
| | - Kai Qian
- Institute of Health and Environmental Ecology, Wenzhou Medical University, University Town, Wenzhou, 325035, China.
| | - Yongchang Chang
- Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, 85013, USA.
| | - Yongjun Du
- Institute of Health and Environmental Ecology, Wenzhou Medical University, University Town, Wenzhou, 325035, China.
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25
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Zhang J, Walker WB, Wang G. Pheromone reception in moths: from molecules to behaviors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 130:109-28. [PMID: 25623339 DOI: 10.1016/bs.pmbts.2014.11.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Male moths detect and find their mates using species-specific sex pheromones emitted by conspecific females. Olfaction plays a vital role in this behavior. Since the first discovery of an insect sex pheromone from the silkmoth Bombyx mori, great efforts have been spent on understanding the sensing of the pheromones in vivo. Much progress has been made in elucidating the molecular mechanisms that mediate chemoreception in insects in the past few decades. In this review, we focus on pheromone reception and detection in moths, from the molecular to the behavioral level. We trace the information pathway from the capture of pheromone by male antennae, binding and transportation to olfactory receptor neurons, receptor activation, signal transduction, molecule inactivation, through brain processing and behavioral response. We highlight the impact of recent studies and also provide our insights into pheromone processing.
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Affiliation(s)
- Jin Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - William B Walker
- Chemical Ecology Research Group, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Guirong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China.
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Li Z, Ni JD, Huang J, Montell C. Requirement for Drosophila SNMP1 for rapid activation and termination of pheromone-induced activity. PLoS Genet 2014; 10:e1004600. [PMID: 25255106 PMCID: PMC4177743 DOI: 10.1371/journal.pgen.1004600] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 07/13/2014] [Indexed: 12/27/2022] Open
Abstract
Pheromones are used for conspecific communication by many animals. In Drosophila, the volatile male-specific pheromone 11-cis vaccenyl acetate (cVA) supplies an important signal for gender recognition. Sensing of cVA by the olfactory system depends on multiple components, including an olfactory receptor (OR67d), the co-receptor ORCO, and an odorant binding protein (LUSH). In addition, a CD36 related protein, sensory neuron membrane protein 1 (SNMP1) is also involved in cVA detection. Loss of SNMP1 has been reported to eliminate cVA responsiveness, and to greatly increase spontaneous activity of OR67d-expressing olfactory receptor neurons (ORNs). Here, we found the snmp1(1) mutation did not abolish cVA responsiveness or cause high spontaneous activity. The cVA responses in snmp1 mutants displayed a delayed onset, and took longer to reach peak activity than wild-type. Most strikingly, loss of SNMP1 caused a dramatic delay in signal termination. The profound impairment in signal inactivation accounted for the previously reported "spontaneous activity," which represented continuous activation following transient exposure to environmental cVA. We introduced the silk moth receptor (BmOR1) in OR67d ORNs of snmp1(1) flies and found that the ORNs showed slow activation and deactivation kinetics in response to the BmOR1 ligand (bombykol). We expressed the bombykol receptor complex in Xenopus oocytes in the presence or absence of the silk moth SNMP1 (BmSNMP) and found that addition of BmSNMP accelerated receptor activation and deactivation. Our results thus clarify SNMP1 as an important player required for the rapid kinetics of the pheromone response in insects.
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Affiliation(s)
- Zhengzheng Li
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jinfei D. Ni
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California
| | - Jia Huang
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California
| | - Craig Montell
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California
- * E-mail:
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Facile functional analysis of insect odorant receptors expressed in the fruit fly: validation with receptors from taxonomically distant and closely related species. Cell Mol Life Sci 2014; 71:4675-80. [PMID: 24816944 DOI: 10.1007/s00018-014-1639-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 04/28/2014] [Accepted: 04/29/2014] [Indexed: 10/25/2022]
Abstract
With the advent of genomic sequences and next-generation sequencing technologies (RNA-Seq), multiple repertoires of olfactory proteins in various insect species are being unraveled. However, functional analyses are lagging behind due in part to the lack of simple and reliable methods for heterologous expression of odorant receptors (ORs). While the Xenopus oocyte recording system fulfills some of this lacuna, this system is devoid of other olfactory proteins, thus testing only the "naked" ORs. Recently, a moth OR was expressed in the majority of neurons in the antennae of the fruit fly using Orco-GAL4 to drive expression of the moth OR. Electroantennogram (EAG) was used to de-orphanize the moth OR, but generic application of this approach was brought to question. Here, we describe that this system works with ORs not only from taxonomically distant insect species (moth), but also closely related species (mosquito), even when the fruit fly has highly sensitive innate ORs for the odorant being tested. We demonstrate that Orco-GAL4 flies expressing the silkworm pheromone receptor, BmorOR1, showed significantly higher responses to the sex pheromone bombykol than the control lines used to drive expression. Additionally, we show that flies expressing an OR from the Southern house mosquito, CquiOR2, gave significantly stronger responses to the cognate odorants indole and 2-methylphenol than the "background noise" recorder from control lines. In summary, we validate the use of Orco-GAL4 driven UAS-OR lines along with EAG analysis as a simple alternative for de-orphanization and functional studies of insect ORs in an intact olfactory system.
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Jiang XJ, Guo H, Di C, Yu S, Zhu L, Huang LQ, Wang CZ. Sequence similarity and functional comparisons of pheromone receptor orthologs in two closely related Helicoverpa species. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 48:63-74. [PMID: 24632377 DOI: 10.1016/j.ibmb.2014.02.010] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 02/12/2014] [Accepted: 02/27/2014] [Indexed: 06/03/2023]
Abstract
The olfactory system of moth species in subfamily Heliothinae is an attractive model to study the evolution of the pheromone reception because they show distinct differentiation in sex pheromone components or ratios that activate pheromone receptors (PRs). However, functional assessment of PRs in closely related species remains largely untried. Here we present a special cloning strategy to isolate full-length cDNAs encoding candidate odorant receptors (ORs) from Helicoverpa armigera (Harm) and Helicoverpa assulta (Hass) on the basis of Heliothis virescens ORs, and investigate the functional properties of PRs to determine how the evolution of moth PRs contribute to intraspecific mating choice and speciation extension. We cloned 11 OR orthologs from H. armigera and 10 from H. assulta. We functionally characterized the responses of PRs of both species to seven pheromone compounds using the heterologous expression system of Xenopus ooctyes. HassOR13 was found to be highly tuned to the sex pheromone component Z11-16:Ald, and unexpectedly, both HarmOR14b and HassOR16 were specific for Z9-14:Ald. However, HarmOR6 and HassOR6 showed much higher specificity to Z9-16:OH than to Z9-16:Ald or Z9-14:Ald. HarmOR11, HarmOR14a, HassOR11 and HassOR14b failed to respond to the tested chemicals. Based on our results and previous research, we can show that some PR orthologs from H. armigera, H. assulta and H. virescens such as OR13s have similar ligand selectivity, but others have different ligand specificity. The combined PR function and sex pheromone component analysis suggests that the evolution of PRs can meet species-specific demands.
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Affiliation(s)
- Xiao-Jing Jiang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, China; Shandong Peanut Research Institute, Qingdao, China
| | - Hao Guo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, China
| | - Chang Di
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, China
| | - Shanlin Yu
- Shandong Peanut Research Institute, Qingdao, China
| | - Ligui Zhu
- Shandong Peanut Research Institute, Qingdao, China
| | - Ling-Qiao Huang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, China
| | - Chen-Zhu Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, China.
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Carle T, Toh Y, Yamawaki Y, Watanabe H, Yokohari F. The antennal sensilla of the praying mantis Tenodera aridifolia: a new flagellar partition based on the antennal macro-, micro- and ultrastructures. ARTHROPOD STRUCTURE & DEVELOPMENT 2014; 43:103-16. [PMID: 24231672 DOI: 10.1016/j.asd.2013.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 10/14/2013] [Accepted: 10/28/2013] [Indexed: 05/26/2023]
Abstract
In insects, the antenna consists of a scapus, a pedicellus, and a flagellum comprising many segments (flagellomeres). These segments possess many morphological types of sensory organs (sensilla) to process multimodal sensory information. We observed the sensilla on flagellomeres in praying mantis (Tenodera aridifolia) with both scanning and transmission electron microscopes. We classified the sensilla into six types: chaetic, campaniform, coelocapitular, basiconic, trichoid and grooved peg sensilla, and inferred their presumptive functions on the basis of their external and internal structures. In addition, based on their distribution, we newly divided the flagellum into 6 distinct parts. This new division leads to a better understanding about the sexual dimorphism and the antennal development in the mantises. The sexual difference in distribution of the grooved peg sensilla suggests that this type of sensilla may play a role in sex-pheromone detection in mantis, which is a rare case of double-walled sensilla mediating this function.
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Affiliation(s)
- Thomas Carle
- Division of Biology, Department of Earth System Science, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan.
| | - Yoshihiro Toh
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 812-8581, Japan
| | - Yoshifumi Yamawaki
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 812-8581, Japan
| | - Hidehiro Watanabe
- Division of Biology, Department of Earth System Science, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan
| | - Fumio Yokohari
- Division of Biology, Department of Earth System Science, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan
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Liu C, Liu Y, Walker WB, Dong S, Wang G. Identification and functional characterization of sex pheromone receptors in beet armyworm Spodoptera exigua (Hübner). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:747-754. [PMID: 23751753 DOI: 10.1016/j.ibmb.2013.05.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 05/14/2013] [Accepted: 05/22/2013] [Indexed: 06/02/2023]
Abstract
In moths, males can detect a distinct blend of several pheromone components by specialized olfactory receptor neurons (ORNs) on the antennae. Four candidate pheromone receptors (PR) with seven transmembrane domains were identified by homology cloning from the antennae of Spodoptera exigua (Sexi). Phylogenetic analyses reveal that all four odorant receptors (OR) belong to pheromone receptor subtypes. Expression patterns revealed that PRs were male-specific in the antenna except for SexiOR11, which was female antenna-biased. Functional analyses of these PRs were conducted using heterologous expression in Xenopus oocytes. SexiOR13 and SexiOR16 were all broadly activated by multiple pheromone components. SexiOR13 responded robustly to the critical pheromone component, Z9, E12-14:OAc and the minor pheromone component, Z9-14:OAc at a concentration of 10(-4) M. Dose-response studies indicate that SexiOR13 was approximately 4 times more sensitive to Z9,E12-14:OAc (EC50 = 3.158 × 10(-6) M) compared to Z9-14:OAc (EC50 = 1.203 × 10(-5) M). While, SexiOR16 responded robustly to the secondary pheromone component Z9-14:OH with high sensitivity (EC50 = 9.690 × 10(-7) M). However, similar tests of the five pheromones with SexiOR6 and SexiOR11 failed to elicit any response. These results provide basic knowledge to further advance research on the molecular mechanisms of pheromone reception.
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Affiliation(s)
- Chengcheng Liu
- 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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Xu P, Leal WS. Probing insect odorant receptors with their cognate ligands: insights into structural features. Biochem Biophys Res Commun 2013; 435:477-82. [PMID: 23673297 DOI: 10.1016/j.bbrc.2013.05.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 05/03/2013] [Indexed: 11/28/2022]
Abstract
Odorant receptors (ORs) are essential for insect survival in the environment and thus are ideal molecular targets for the design of insect-inspired modern green chemicals to control populations of agricultural pests and insects of medical importance. Although insect ORs are known for more than a decade, their structural biology is still in its infancy. Here, we unravel the first structural features of ORs from the malaria mosquito, the Southern house mosquito and the silkworm moth. The second extracellular loops (ECL-2s) of their predicted structures are much longer than ECL-1s and ECL-3s. The 27 amino-acid-residue-long of the ECL-2s in mosquito and the 43 amino-acid-residue-long ECL2s in moth ORs are well-conserved. About one-third of the residues are identical, including 3-4 Pro residues. Thorough examination of well-conserved residues in these structures, by point mutation and functional assay with the Xenopus oocyte recording system, strongly suggest that these "loops" include three β-turns and some degree of folding. In the Southern house mosquito three Pro residues in ECL-2 are essential for full activation of the receptor, which is finely tuned to the oviposition attractant 3-methylindole. Additionally, the "corner residues" of prolines, including Gly, Tyr, and Leu are functionally important thus suggesting that turns are stabilized not only by backbone hydrogen bonds, but also by side-chain interactions. Examination of ECL-2s from a distant taxonomical group suggests these ECL-2 loops might be functionally important in all insect ORs. Two of the four Pro residues in the predicted ECL-2 of the bombykol receptor in the silkworm moth, BmorOR1, are essential for function. Experimental evidence indicates that these loops may not be specificity determinants, but they may form a cover to the yet-to-be-identified membrane embedded binding cavities of insect ORs.
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Affiliation(s)
- Pingxi Xu
- Honorary Maeda-Duffey Laboratory, University of California, Davis, CA 95616, USA
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Poivet E, Rharrabe K, Monsempes C, Glaser N, Rochat D, Renou M, Marion-Poll F, Jacquin-Joly E. The use of the sex pheromone as an evolutionary solution to food source selection in caterpillars. Nat Commun 2013; 3:1047. [PMID: 22948829 DOI: 10.1038/ncomms2050] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 08/03/2012] [Indexed: 11/09/2022] Open
Abstract
Sex pheromones are released by adults of a species to elicit a sexual interaction with the other sex of the same species. Here we report an unexpected effect of a moth sex pheromone on the caterpillars of the same species. We demonstrate that larvae of the cotton leafworm Spodoptera littoralis are attracted by the moth sex pheromone and that this phenomenon is independent of sex determination. In addition, we show that the olfactory sensilla carried by the caterpillar antennae are sensitive to the pheromone and that the caterpillar sensilla express pheromone-binding proteins that are used by adult antennae to bind pheromone components. Finally, we demonstrate that the larvae are preferentially attracted to a food source when it contains the sex pheromone main component. A possible interpretation of these results is that the sex pheromone is used to promote food search in caterpillars, opening potential new routes for insect pest management.
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Affiliation(s)
- Erwan Poivet
- INRA, UMR 1272 INRA-UPMC Physiologie de l'Insecte: Signalisation et Communication, Route de Saint-Cyr, F-78026 Versailles Cedex, France
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Katti S, Lokhande N, González D, Cassill A, Renthal R. Quantitative analysis of pheromone-binding protein specificity. INSECT MOLECULAR BIOLOGY 2013; 22:31-40. [PMID: 23121132 PMCID: PMC3552018 DOI: 10.1111/j.1365-2583.2012.01167.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Many pheromones have very low water solubility, posing experimental difficulties for quantitative binding measurements. A new method is presented for determining thermodynamically valid dissociation constants for ligands binding to pheromone-binding proteins, using β-cyclodextrin as a solubilizer and transfer agent. The method is applied to LUSH, a Drosophila odorant-binding protein that binds the pheromone 11-cis vaccenyl acetate (cVA). Refolding of LUSH expressed in Escherichia coli was assessed by measuring N-phenyl-1-naphthylamine (NPN) binding and Förster resonance energy transfer between LUSH tryptophan 123 (W123) and NPN. Binding of cVA was measured from quenching of W123 fluorescence as a function of cVA concentration. The equilibrium constant for transfer of cVA between β-cyclodextrin and LUSH was determined from a linked equilibria model. This constant, multiplied by the β-cyclodextrin-cVA dissociation constant, gives the LUSH-cVA dissociation constant: ∼100 nM. It was also found that other ligands quench W123 fluorescence. The LUSH-ligand dissociation constants were determined to be ∼200 nM for the silk moth pheromone bombykol and ∼90 nM for methyl oleate. The results indicate that the ligand-binding cavity of LUSH can accommodate a variety ligands with strong binding interactions. Implications of this for the Laughlin, Ha, Jones and Smith model of pheromone reception are discussed.
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Affiliation(s)
- S Katti
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
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Vásquez GM, Syed Z, Estes PA, Leal WS, Gould F. Specificity of the receptor for the major sex pheromone component in Heliothis virescens. JOURNAL OF INSECT SCIENCE (ONLINE) 2013; 13:160. [PMID: 24773407 PMCID: PMC4015405 DOI: 10.1673/031.013.16001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 10/29/2012] [Indexed: 06/03/2023]
Abstract
In a previous study, the Drosophila melanogaster OR67d(GAL4);UAS system was used to functionally characterize the receptor for the major component of the sex pheromone in the tobacco budworm, Heliothis virescens Fabricius (Lepidoptera: Noctuidae), HvOR13. Electrophysiological and behavioral assays showed that transgenic flies expressing HvOR13 responded to (Z)-11-hexadecenal (Z11-16:Ald). However, tests were not performed to determine whether these flies would also respond to secondary components of the H. virescens sex pheromone. Thus, in this study the response spectrum of HvOR13 expressed in this system was examined by performing single cell recordings from odor receptor neuron in trichoid T1 sensilla on antennae of two Or67d(GAL4 [1]); UAS-HvOR13 lines stimulated with Z11-16:Ald and six H. virescens secondary pheromone components. Fly courtship assays were also performed to examine the behavioral response of the Or67d(GAL4[1]); UAS-HvOR13 flies to Z11-16:Ald and the secondary component Z9-14:Ald. Our combined electrophysiological and behavioral studies indicated high specificity and sensitivity of HvOR13 to Z11-16:Ald. Interestingly, a mutation leading to truncation in the HvOR13 C-terminal region affected but did not abolish pheromone receptor response to Z11-16:Ald. The findings are assessed in relationship to other HvOR13 heterologous expression studies, and the role of the C-terminal domain in receptor function is discussed. A third line expressing HvOR15 was also tested but did not respond to any of the seven pheromone components.
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Affiliation(s)
- Gissella M. Vásquez
- Department of Entomology and W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Zainulabeuddin Syed
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Patricia A. Estes
- Department of Biological Sciences and W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Walter S. Leal
- Department of Entomology, Honorary Maeda-Duffey Laboratory, University of California, Davis, CA 95616, USA
| | - Fred Gould
- Department of Entomology and W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695, USA
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Leal WS. Odorant reception in insects: roles of receptors, binding proteins, and degrading enzymes. ANNUAL REVIEW OF ENTOMOLOGY 2013; 58:373-91. [PMID: 23020622 DOI: 10.1146/annurev-ento-120811-153635] [Citation(s) in RCA: 1037] [Impact Index Per Article: 94.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Our knowledge of the molecular basis of odorant reception in insects has grown exponentially over the past decade. Odorant receptors (ORs) from moths, fruit flies, mosquitoes, and the honey bees have been deorphanized, odorant-degrading enzymes (ODEs) have been isolated, and the functions of odorant-binding proteins (OBPs) have been unveiled. OBPs contribute to the sensitivity of the olfactory system by transporting odorants through the sensillar lymph, but there are competing hypotheses on how they act at the end of the journey. A few ODEs that have been demonstrated to degrade odorants rapidly may act in signal inactivation alone or in combination with other molecular traps. Although ORs in Drosophila melanogaster respond to multiple odorants and seem to work in combinatorial code involving both periphery and antennal lobes, reception of sex pheromones by moth ORs suggests that their labeled lines rely heavily on selectivity at the periphery.
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Affiliation(s)
- Walter S Leal
- Honorary Maeda-Duffey Laboratory, University of California, Davis, California 95616, USA.
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Xu P, Hooper AM, Pickett JA, Leal WS. Specificity determinants of the silkworm moth sex pheromone. PLoS One 2012; 7:e44190. [PMID: 22957053 PMCID: PMC3434217 DOI: 10.1371/journal.pone.0044190] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 07/30/2012] [Indexed: 11/19/2022] Open
Abstract
The insect olfactory system, particularly the peripheral sensory system for sex pheromone reception in male moths, is highly selective, but specificity determinants at the receptor level are hitherto unknown. Using the Xenopus oocyte recording system, we conducted a thorough structure-activity relationship study with the sex pheromone receptor of the silkworm moth, Bombyx mori, BmorOR1. When co-expressed with the obligatory odorant receptor co-receptor (BmorOrco), BmorOR1 responded in a dose-dependent fashion to both bombykol and its related aldehyde, bombykal, but the threshold of the latter was about one order of magnitude higher. Solubilizing these ligands with a pheromone-binding protein (BmorPBP1) did not enhance selectivity. By contrast, both ligands were trapped by BmorPBP1 leading to dramatically reduced responses. The silkworm moth pheromone receptor was highly selective towards the stereochemistry of the conjugated diene, with robust response to the natural (10E,12Z)-isomer and very little or no response to the other three isomers. Shifting the conjugated diene towards the functional group or elongating the carbon chain rendered these molecules completely inactive. In contrast, an analogue shortened by two omega carbons elicited the same or slightly higher responses than bombykol. Flexibility of the saturated C1–C9 moiety is important for function as addition of a double or triple bond in position 4 led to reduced responses. The ligand is hypothesized to be accommodated by a large hydrophobic cavity within the helical bundle of transmembrane domains.
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Affiliation(s)
- Pingxi Xu
- Honorary Maeda-Duffey Laboratory, University of California Davis, Davis, California, United States of America
| | - Antony M. Hooper
- Rothamsted Research, West Common, Harpenden, Hertfordshire, United Kingdom
| | - John A. Pickett
- Rothamsted Research, West Common, Harpenden, Hertfordshire, United Kingdom
| | - Walter S. Leal
- Honorary Maeda-Duffey Laboratory, University of California Davis, Davis, California, United States of America
- * E-mail:
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37
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Montagné N, Chertemps T, Brigaud I, François A, François MC, de Fouchier A, Lucas P, Larsson MC, Jacquin-Joly E. Functional characterization of a sex pheromone receptor in the pest moth Spodoptera littoralis by heterologous expression in Drosophila. Eur J Neurosci 2012; 36:2588-96. [PMID: 22748123 DOI: 10.1111/j.1460-9568.2012.08183.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Moth sex pheromone communication is recognised as a long-standing model for insect olfaction studies, and a widespread knowledge has been accumulated on this subject thanks to numerous chemical, electrophysiological and behavioural studies. A key step has been the identification of candidate sex pheromone receptors, opening new routes to understanding the specificity and sensitivity of this communication system, but only few of these receptors have as yet been functionally characterised. In this context, we aim at unravelling the molecular bases of pheromone reception in the noctuid moth Spodoptera littoralis. Taking advantage of a collection of antennal-expressed sequence tags, we previously identified three fragments of candidate pheromone receptors in this species. Here, we report full-length cloning of one of these receptors, named SlitOR6. Both sequence and expression pattern analyses were consistent with its annotation as a pheromone receptor, which we further confirmed by functional characterization. Using Drosophila antennae as a heterologous expression system, we identified a single component of the pheromone blend of S. littoralis, (Z,E)-9,12-tetradecadienyl acetate, as the ligand of SlitOR6. Two strategies were employed: (i) expressing SlitOR6 in the majority of Drosophila olfactory neurons, in addition to endogenous receptors, and monitoring the responses to pheromone stimuli by electroantennography; (ii) replacing the Drosophila pheromone receptor OR67d with SlitOR6 and monitoring the response by single sensillum recordings. Results were fully congruent and responses to (Z,E)-9,12-tetradecadienyl acetate were highly specific in both heterologous systems. This approach appears to be efficient and reliable for studying moth pheromone receptors in an in vivo context.
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Affiliation(s)
- Nicolas Montagné
- UPMC - Université Paris 6, UMR-A 1272 Physiologie de l'Insecte : Signalisation et Communication, Paris, France.
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Li KM, Ren LY, Zhang YJ, Wu KM, Guo YY. Knockdown of Microplitis mediator Odorant Receptor Involved in the Sensitive Detection of Two Chemicals. J Chem Ecol 2012; 38:287-94. [DOI: 10.1007/s10886-012-0085-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 02/13/2012] [Accepted: 02/17/2012] [Indexed: 11/28/2022]
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Abstract
In this issue of Chemical Senses, Baker et al. propose a provocative and intriguing explanation for a commonly observed phenomenon in moth chemocommunication. Sex pheromones in moths typically consist of mixtures of long-chain unsaturated compounds in specific ratios. These ratios are correspondingly detected by male moths using separate olfactory sensory neurons for each pheromone component housed singly or multiply in long trichoid sensilla on the antennal surface. These neurons are often present in different proportions, typically with the neuron responding to the highest ratio component present in greatest abundance or with the largest dendritic diameter. In their article, Baker et al. postulate that these physical differences in neuron magnitudes arise to compensate for the higher molecular flux present with the most abundant pheromone components. Such a suggestion raises several questions concerning the physiological and behavioral nature of pheromone communication. Specifically, is the flux in a natural pheromone plume high enough to warrant increased flux detection for the most abundant components? Second, how can changes in neuronal number or size lead to increased flux detection? And finally, how would this increased flux detection be accomplished at molecular, cellular, and ultimately network scales? We address each of these questions and propose future experiments that could offer insight into the stimulating proposition raised by Baker et al.
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Affiliation(s)
- Shannon B Olsson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knoell Strasse 8, Jena, DE 07745, Germany.
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Abstract
Great progress has been made in the field of insect olfaction in recent years. Receptors, neurons, and circuits have been defined in considerable detail, and the mechanisms by which they detect, encode, and process sensory stimuli are being unraveled. We provide a guide to recent progress in the field, with special attention to advances made in the genetic model organism Drosophila. We highlight key questions that merit additional investigation. We then present our view of how recent advances may be applied to the control of disease-carrying insects such as mosquitoes, which transmit disease to hundreds of millions of people each year. We suggest how progress in defining the basic mechanisms of insect olfaction may lead to means of disrupting host-seeking and other olfactory behaviors, thereby reducing the transmission of deadly diseases.
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Syed Z, Pelletier J, Flounders E, Chitolina RF, Leal WS. Generic insect repellent detector from the fruit fly Drosophila melanogaster. PLoS One 2011; 6:e17705. [PMID: 21436880 PMCID: PMC3059203 DOI: 10.1371/journal.pone.0017705] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Accepted: 02/08/2011] [Indexed: 11/18/2022] Open
Abstract
Background Insect repellents are prophylactic tools against a number of vector-borne
diseases. There is growing demand for repellents outperforming DEET in cost
and safety, but with the current technologies R&D of a new product takes
almost 10 years, with a prohibitive cost of $30 million dollar in
part due to the demand for large-scale synthesis of thousands of test
compounds of which only 1 may reach the market. R&D could be expedited
and cost dramatically reduced with a molecular/physiological target to
streamline putative repellents for final efficacy and toxicological
tests. Methodology Using olfactory-based choice assay we show here that the fruit fly is
repelled by not only DEET, but also IR3535 and picaridin thus suggesting
they might have “generic repellent detector(s),” which may be of
practical applications in new repellent screenings. We performed single unit
recordings from all olfactory sensilla in the antennae and maxillary palps.
Although the ab3A neuron in the wild type flies responded to picaridin, it
was unresponsive to DEET and IR3535. By contrast, a neuron housed in the
palp basiconic sensilla pb1 responded to DEET, IR3535, and picaridin, with
apparent sensitivity higher than that of the DEET detectors in the
mosquitoes Culex quinquefasciatus and Aedes
aegypti. DmOr42a was transplanted from pb1 to the “empty
neuron” and showed to be sensitive to the three insect repellents. Conclusions For the first time we have demonstrated that the fruit fly avoids not only
DEET but also IR3535 and picaridin, and identified an olfactory receptor
neuron (ORN), which is sensitive to these three major insect repellents. We
have also identified the insect repellent-sensitive receptor, DmOr42a. This
generic detector fulfils the requirements for a simplified bioassay for
early screening of test insect repellents.
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Affiliation(s)
- Zainulabeuddin Syed
- Department of Entomology, University of California Davis, Davis,
California, United States of America
| | - Julien Pelletier
- Department of Entomology, University of California Davis, Davis,
California, United States of America
| | - Eric Flounders
- Department of Entomology, University of California Davis, Davis,
California, United States of America
| | - Rodrigo F. Chitolina
- Department of Entomology, University of California Davis, Davis,
California, United States of America
| | - Walter S. Leal
- Department of Entomology, University of California Davis, Davis,
California, United States of America
- * E-mail:
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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] [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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He X, Tzotzos G, Woodcock C, Pickett JA, Hooper T, Field LM, Zhou JJ. Binding of the general odorant binding protein of Bombyx mori BmorGOBP2 to the moth sex pheromone components. J Chem Ecol 2010; 36:1293-305. [PMID: 20981477 DOI: 10.1007/s10886-010-9870-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 09/16/2010] [Accepted: 09/27/2010] [Indexed: 11/26/2022]
Abstract
Insects use olfactory cues to locate hosts and mates. Pheromones and other semiochemicals are transported in the insect antenna by odorant-binding proteins (OBPs), which ferry the signals across the sensillum lymph to the olfactory receptors (ORs). In the silkworm, Bombyx mori (L.), two OBP subfamilies, the pheromone-binding proteins (PBPs) and the general odorant-binding proteins (GOBPs), are thought to be involved in both sensing and transporting the sex pheromone, bombykol [(10E,12Z)-hexadecadien-1-ol], and host volatiles, respectively. Quantitative examination of transcript levels showed that BmorPBP1 and BmorGOBP2 are expressed specifically at very high levels in the antennae, consistent with their involvement in olfaction. A partitioning binding assay, along with other established assays, showed that both BmorPBP1 and BmorGOBP2 bind to the main sex pheromone component, bombykol. BmorPBP1 also binds equally well to the other major pheromone component, bombykal [(10E,12Z)-hexadecadienal], whereas BmorGOBP2 discriminates between the two ligands. The pheromone analogs (10E,12Z)-hexadecadienyl acetate and (10E,12Z)-octadecadien-1-ol bind to both OBPs more strongly than does bombykol, suggesting that they could act as potential blockers of the response to sex pheromone by the male. These results are supported by further comparative studies of molecular docking, crystallographic structures, and EAG recording as a measure of biological response.
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Affiliation(s)
- Xiaoli He
- Department of Biological Chemistry, Rothamsted Research, Harpenden, UK
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