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Zafar Z, Fatima S, Bhatti MF, Shah FA, Saud Z, Butt TM. Odorant Binding Proteins (OBPs) and Odorant Receptors (ORs) of Anopheles stephensi: Identification and comparative insights. PLoS One 2022; 17:e0265896. [PMID: 35316281 PMCID: PMC8939812 DOI: 10.1371/journal.pone.0265896] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 03/09/2022] [Indexed: 01/01/2023] Open
Abstract
Anopheles stephensi is an important vector of malaria in the South Asia, the Middle East, and Eastern Africa. The olfactory system of An. stephensi plays an important role in host-seeking, oviposition, and feeding. Odorant binding proteins (OBPs) are globular proteins that play a pivotal role in insect olfaction by transporting semiochemicals through the sensillum lymph to odorant receptors (ORs). Custom motifs designed from annotated OBPs of Aedes aegypti, Drosophila melanogaster, and Anopheles gambiae were used for the identification of putative OBPs from protein sequences of the An. stephensi Indian strain. Further, BLASTp was also performed to identify missing OBPs and ORs. Subsequently, the presence of domains common to OBPs was confirmed. Identified OBPs were further classified into three sub-classes. Phylogenetic and syntenic analyses were carried out to find homology, and thus the evolutionary relationship between An. stephensi OBPs and ORs with those of An. gambiae, Ae. aegypti and D. melanogaster. Gene structure and physicochemical properties of the OBPs and ORs were also predicted. A total of 44 OBPs and 45 ORs were predicted from the protein sequences of An. stephensi. OBPs were further classified into the classic (27), atypical (10) and plus-C (7) OBP subclasses. The phylogeny revealed close relationship of An. stephensi OBPs and ORs with An. gambiae homologs whereas only five OBPs and two ORs of An. stephensi were related to Ae. aegypti OBPs and ORs, respectively. However, D. melanogaster OBPs and ORs were distantly rooted. Synteny analyses showed the presence of collinear block between the OBPs and ORs of An. stephensi and An. gambiae as well as Ae. aegypti’s. No homology was found with D. melanogaster OBPs and ORs. As an important component of the olfactory system, correctly identifying a species’ OBPs and ORs provide a valuable resource for downstream translational research that will ultimately aim to better control the malaria vector An. stephensi.
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Affiliation(s)
- Zeeshan Zafar
- Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Sector H-12, Islamabad, Pakistan
| | - Sidra Fatima
- Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Sector H-12, Islamabad, Pakistan
| | - Muhammad Faraz Bhatti
- Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Sector H-12, Islamabad, Pakistan
| | | | - Zack Saud
- Department of Biological Sciences, Swansea University, Swansea, United Kingdom
| | - Tariq M Butt
- Department of Biological Sciences, Swansea University, Swansea, United Kingdom
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Li L, Gao X, Gui H, Lan M, Zhu J, Xie Y, Zhan Y, Wang Z, Li Z, Ye M, Wu G. Identification and preliminary characterization of chemosensory-related proteins in the gall fly, Procecidochares utilis by transcriptomic analysis. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 36:100724. [PMID: 32836214 DOI: 10.1016/j.cbd.2020.100724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/24/2020] [Accepted: 08/05/2020] [Indexed: 01/20/2023]
Abstract
Chemoreception is critical for insect behaviors such as foraging, host searching and oviposition. The process of chemoreception is mediated by a series of proteins, including odorant-binding proteins (OBPs), gustatory receptors (GRs), odorant receptors (ORs), ionotropic receptors (IRs), chemosensory proteins (CSPs) and sensory neuron membrane proteins (SNMPs). The tephritid stem gall fly, Procecidochares utilis Stone, is a type of egg parasitic insect, which is an effective biological control agent for the invasive weed Ageratina adenophora in many countries. However, the study of molecular components related to the olfactory system of P. utilis has not been investigated. Here, we conducted the developmental transcriptome (egg, first-third instar larva, pupa, female and male adult) of P. utilis using next-generation sequencing technology and identified a total of 133 chemosensory genes, including 40 OBPs, 29 GRs, 24 ORs, 28 IRs, 6 CSPs, and 6 SNMPs. The sequences of these candidate chemosensory genes were confirmed by BLAST, and phylogenetic analysis was performed. Quantitative real-time PCR (qRT-PCR) confirmed that the expression levels of the candidate OBPs varied at the different developmental stages of P. utilis with most OBPs expressed mainly in the pupae, female and male adults but scarcely in eggs and larvae, which was consistent with the differentially expressed genes (DEGs) analysis using the fragments per kilobase per million fragments (FPKM) value. Our results provide a significant contribution towards the knowledge of the set of chemosensory proteins and help advance the use of P. utilis as biological control agents.
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Affiliation(s)
- Lifang Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
| | - Xi Gao
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
| | - Huamin Gui
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
| | - Mingxian Lan
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
| | - Jiaying Zhu
- Key Laboratory of Forest Disaster Warning and Control of Yunnan Province, Southwest Forestry University, Kunming 650224, China
| | - Yonghui Xie
- Kunming Branch of Yunnan Provincial Tobacco Company, Kunming 650021, China
| | - Youguo Zhan
- Kunming Branch of Yunnan Provincial Tobacco Company, Kunming 650021, China
| | - Zhijiang Wang
- Kunming Branch of Yunnan Provincial Tobacco Company, Kunming 650021, China
| | - Zhengyue Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
| | - Min Ye
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China.
| | - Guoxing Wu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China.
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Ghavami MB, Khoeini S, Djadid ND. Molecular characteristics of odorant-binding protein 1 in Anopheles maculipennis. Malar J 2020; 19:29. [PMID: 31952536 PMCID: PMC6969430 DOI: 10.1186/s12936-019-3058-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 12/08/2019] [Indexed: 11/10/2022] Open
Abstract
Background Anopheles maculipennis complex, the historic vector of malaria, causes serious medical problems worldwide and exhibits different behaviours. Studying the odorant-binding proteins (OBPs), which influence the chemosensory system and behavioural responses, is essential to understanding the population structure and developing effective control measures against this vector. The present study was designed to identify and analyse the obp1 gene in An. maculipennis. Methods Adults of An. maculipennis sensu stricto were collected in Zanjan Province, northwest of Iran, and gDNAs of female mosquitoes were extracted. Fragments of An. maculipennis obp1 (Amacobp1) gene were amplified using degenerate and specific primers, and some of amplicons were selected for sequencing. Results Analysis of amplified products identified that the sequence of Amacobp1 gene was 1341 bp long. This gene contains three exons (5′, internal, and 3′of 160, 256, and 18 bp, respectively) and encodes 144 amino acids. The sizes of introns I and II in deduced gene are 268 and 358 nucleotides, respectively. The amino acid sequence in the C-terminal of AmacOBP1 is similar to that of major malaria vector Anopheles species. However, its N-terminal has a specific signal peptide with 19 amino acids. This peptide is conserved in different studied populations, and its sequence of amino acids shows the most variation among anopheline species. Conclusions Degenerate primers in this study are suggested for studying obp1 gene in Anopheles species. Amacobp1 gene is proposed as a molecular marker for the detection of intraspecific ecotypes and diagnosis of different species within Maculipennis Group. Moreover, the N-terminal of AmacOBP1 peptide is recommended as a molecular marker to identify the Amacobp1 expression patterns in different chemosensory organs for assessing the molecular mechanisms and developing novel behavioural disturbance agents to control An. maculipennis.
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Affiliation(s)
- Mohammad Bagher Ghavami
- Department of Medical Entomology and Vector Control, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
| | - Sakineh Khoeini
- Department of Medical Entomology and Vector Control, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
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Li H, Wang P, Zhang L, Xu X, Cao Z, Zhang L. Expressions of Olfactory Proteins in Locust Olfactory Organs and a Palp Odorant Receptor Involved in Plant Aldehydes Detection. Front Physiol 2018; 9:663. [PMID: 29915543 PMCID: PMC5994405 DOI: 10.3389/fphys.2018.00663] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 05/14/2018] [Indexed: 12/12/2022] Open
Abstract
The main chemosensory organs of locusts consisted of the antennae and the mouthparts (maxillary and labial palps), which are suggested to perform different functions. However, very few are known about the differences of these two organs at molecular level. To understand the differences of locust antennae and palps in olfaction, the electrophysiological response and olfactory gene expression of these two organs were conducted. Our electrophysiological experiments with Locusta migratoria showed that the responses of mouthpart palps and antennae to odorants are quite different. Only a few odorants, such as (E,E)-2,4-hexadienal and (E,E)-2,4-heptadienal, elicited stronger electrophysiological responses of both maxillary and labial palps in comparison to the antennae. Additionally, we obtained 114 and 11 putative odorant receptor (OR) gene segments from the antennal and palp transcriptomes, respectively. Two novel odorant-binding proteins (OBPs; OBP15 and OBP16) and one novel OR (OR142) were identified for the first time. Out of the 16 OBP genes tested in RT-PCR and qPCR analyses, OBP8 was highly expressed in the nymphal palps. OBP4, OBP10, and OBP16 were only detected in the antennae. The other 11 OBP genes were jointly expressed in both antennae and palps. The relative expression level of OBP6 in male palps was much higher than that of female palps. Furthermore, for the 11 OR genes identified in palp transcriptome, the expression levels of OR12, OR13, OR14, and OR18 in the palps were significantly higher than those in the antennae. The OR12 in palps was demonstrated to be involved in detection of hexanal and E-2-hexenal, as well as (E,E)-2,4-heptadienal. Our results provide information on the different olfactory roles of locust antennae and palps at the molecular level.
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Affiliation(s)
- Hongwei Li
- Department of Entomology, China Agricultural University, Beijing, China
| | - Peng Wang
- Department of Entomology, China Agricultural University, Beijing, China
| | - Liwei Zhang
- Department of Entomology, China Agricultural University, Beijing, China
| | - Xiao Xu
- Department of Entomology, China Agricultural University, Beijing, China
| | - Zewen Cao
- Department of Entomology, China Agricultural University, Beijing, China
| | - Long Zhang
- Department of Entomology, China Agricultural University, Beijing, China
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Das De T, Thomas T, Verma S, Singla D, Chauhan C, Srivastava V, Sharma P, Kumari S, Tevatiya S, Rani J, Hasija Y, Pandey KC, Dixit R. A Synergistic Transcriptional Regulation of Olfactory Genes Drives Blood-Feeding Associated Complex Behavioral Responses in the Mosquito Anopheles culicifacies. Front Physiol 2018; 9:577. [PMID: 29875685 PMCID: PMC5974117 DOI: 10.3389/fphys.2018.00577] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 05/01/2018] [Indexed: 02/05/2023] Open
Abstract
Decoding the molecular basis of host seeking and blood feeding behavioral evolution/adaptation in the adult female mosquitoes may provide an opportunity to design new molecular strategy to disrupt human-mosquito interactions. Although there is a great progress in the field of mosquito olfaction and chemo-detection, little is known about the sex-specific evolution of the specialized olfactory system of adult female mosquitoes that enables them to drive and manage the complex blood-feeding associated behavioral responses. A comprehensive RNA-Seq analysis of prior and post blood meal olfactory system of An. culicifacies mosquito revealed a minor but unique change in the nature and regulation of key olfactory genes that may play a pivotal role in managing diverse behavioral responses. Based on age-dependent transcriptional profiling, we further demonstrated that adult female mosquito's chemosensory system gradually learned and matured to drive the host-seeking and blood feeding behavior at the age of 5-6 days. A time scale expression analysis of Odorant Binding Proteins (OBPs) unravels unique association with a late evening to midnight peak biting time. Blood meal-induced switching of unique sets of OBP genes and Odorant Receptors (Ors) expression coincides with the change in the innate physiological status of the mosquitoes. Blood meal follows up experiments further provide enough evidence that how a synergistic and concurrent action of OBPs-Ors may drive "prior and post blood meal" associated complex behavioral events. A dominant expression of two sensory appendages proteins (SAP-1 & SAP2) in the legs of An. culicifacies suggests that this mosquito species may draw an extra advantage of having more sensitive appendages than An. stephensi, an urban malarial vector in the Indian subcontinents. Finally, our molecular modeling analysis predicts crucial amino acid residues for future functional characterization of the sensory appendages proteins which may play a central role in regulating multiple behaviors of An. culicifacies mosquito. SIGNIFICANCE Evolution and adaptation of blood feeding behavior not only favored the reproductive success of adult female mosquitoes but also make them important disease-transmitting vectors. An environmental exposure after emergence may favor the broadly tuned olfactory system of mosquitoes to drive complex behavioral responses. But, how these olfactory derived genetic factors manage female specific "pre and post" blood meal associated complex behavioral responses are not well known. Our findings suggest that a synergistic action of olfactory factors may govern an innate to prime learning strategy to facilitate rapid blood meal acquisition and downstream behavioral activities. A species-specific transcriptional profiling and an in-silico analysis predict that "sensory appendages protein" may be a unique target to design disorientation strategy against the mosquito Anopheles culicifacies.
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Affiliation(s)
- Tanwee Das De
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India.,Department of Biotechnology, Delhi Technological University, Rohini, India
| | - Tina Thomas
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Sonia Verma
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Deepak Singla
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Charu Chauhan
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Vartika Srivastava
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Punita Sharma
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Seena Kumari
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Sanjay Tevatiya
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Jyoti Rani
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
| | - Yasha Hasija
- Department of Biotechnology, Delhi Technological University, Rohini, India
| | - Kailash C Pandey
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India.,Department of Biochemistry, National Institute for Research in Environmental Health, Indian Council of Medical Research, Bhopal, India
| | - Rajnikant Dixit
- Laboratory of Host-Parasite Interaction Studies, National Institute of Malaria Research, Dwarka, India
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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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Zhang J, Luo D, Wu P, Li H, Zhang H, Zheng W. Identification and expression profiles of novel odorant binding proteins and functional analysis of OBP99a in Bactrocera dorsalis. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2018; 98:e21452. [PMID: 29450902 DOI: 10.1002/arch.21452] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Odorant-binding proteins (OBPs) in insects are essential for mating and oviposition host selection. How these OBPs respond to different hosts at the mRNA level and their effects on behavior remain poorly characterized. The oriental fruit fly Bactrocera dorsalis is a highly invasive agricultural pest with an extremely broad host range and high fecundity. Based on our previously constructed B. dorsalis transcriptome, six OBPs that were differentially expressed during three different physiological adult stages were identified. A phylogenetic tree was constructed to illustrate the relationships of these six OBPs with OBP sequences from three other dipteran species (Drosophila melanogaster, Anopheles gambiae, and Ceratitis capitata). The spatiotemporal expression profiles of the six OBPs were analyzed using quantitative real-time PCR. Our results revealed that OBP19c, OBP44a, OBP99a, and OBP99d were abundantly expressed from the prepupa stage to the adult stage, and most of the OBPs were mainly expressed in the head, wings, and antennae. The expression levels of these OBPs were upregulated when female flies were exposed to their preferred hosts. Silencing OBP99a resulted fewer eggs being laid compared with the control group when the females were exposed to their preferred host, that is, banana, whereas more eggs were laid when a non-preferred host, that is, tomato, was used. Furthermore, silencing OBP99a led to sexually dimorphic mating behavior. dsOBP99a-injected males dramatically reduced courtship, whereas enhanced courtship was observed in the treated females. These data indicate that OBPs may participate in different biological processes of B. dorsalis. Our study will provide insight into the molecular mechanism of chemoreception and help develop ecologically friendly pest-control strategies.
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Affiliation(s)
- Jing Zhang
- State Key Laboratory of Agricultural Microbiology, Key Laboratory of Horticultural Plant Biology, Ministry of Education and Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Deye Luo
- State Key Laboratory of Agricultural Microbiology, Key Laboratory of Horticultural Plant Biology, Ministry of Education and Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Peng Wu
- State Key Laboratory of Agricultural Microbiology, Key Laboratory of Horticultural Plant Biology, Ministry of Education and Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Haozhe Li
- State Key Laboratory of Agricultural Microbiology, Key Laboratory of Horticultural Plant Biology, Ministry of Education and Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Hongyu Zhang
- State Key Laboratory of Agricultural Microbiology, Key Laboratory of Horticultural Plant Biology, Ministry of Education and Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Weiwei Zheng
- State Key Laboratory of Agricultural Microbiology, Key Laboratory of Horticultural Plant Biology, Ministry of Education and Institute of Urban and Horticultural Entomology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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Yuan X, Jiang YD, Wang GY, Yu H, Zhou WW, Liu S, Yang MF, Cheng J, Gurr GM, Way MO, Zhu ZR. Odorant-Binding Proteins and Chemosensory Proteins from an Invasive Pest Lissorhoptrus oryzophilus (Coleoptera: Curculionidae). ENVIRONMENTAL ENTOMOLOGY 2016; 45:1276-1286. [PMID: 27569597 DOI: 10.1093/ee/nvw111] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/01/2016] [Indexed: 06/06/2023]
Abstract
The rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), is a serious pest species both in its original distribution region of northern America and its invaded regions of eastern Asia and southern Europe. The odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) play important roles in host and mate locating, thus might play a significant role in the success of the species as an invader, which has not been characterized yet. We identified 10 OBPs and 5 CSPs in L. oryzophilus and investigated the expression profiles of these genes in various tissues by quantitative real-time PCR. Five classic OBPs were predominantly expressed in the antennae. CSPs were expressed ubiquitously with particularly high transcript levels in antennae, legs, and wings. Three antenna-specific OBPs (LoOBP1, 8, 11) were up-regulated following 1-3 d of food deprivation and down-regulated afterward. These findings suggest most classic OBPs are likely involved in chemoreception whereas CSPs as well as the minus-C OBPs may have broader physiological functions, which in turn may help to understand the molecular aspects of chemical communication in this invasive insect.
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Affiliation(s)
- Xin Yuan
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Yan-Dong Jiang
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Gui-Yao Wang
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Hang Yu
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Wen-Wu Zhou
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Su Liu
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Mao-Fa Yang
- Institute of Entomology, Guizhou University, Guiyang, China
| | - Jiaan Cheng
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
| | - Geoff M Gurr
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; ) Graham Centre for Agricultural Innovation, Charles Sturt University, Orange, NSW, Australia
| | - Michael O Way
- Texas A&M AgriLife Research and Extension Center, Beaumont, TX
| | - Zeng-Rong Zhu
- State Key Laboratory of Rice Biology and Key Laboratory of Agricultural Entomology, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China (; ; ; ; ; ; ; ; )
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He X, He ZB, Zhang YJ, Zhou Y, Xian PJ, Qiao L, Chen B. Genome-wide identification and characterization of odorant-binding protein (OBP) genes in the malaria vector Anopheles sinensis (Diptera: Culicidae). INSECT SCIENCE 2016; 23:366-376. [PMID: 26970073 DOI: 10.1111/1744-7917.12333] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/03/2016] [Indexed: 06/05/2023]
Abstract
Anopheles sinensis is a major malaria vector. Insect odorant-binding proteins (OBPs) may function in the reception of odorants in the olfactory system. The classification and characterization of the An. sinensis OBP genes have not been systematically studied. In this study, 64 putative OBP genes were identified at the whole-genome level of An. sinensis based on the comparison between OBP conserved motifs, PBP_GOBP, and phylogenetic analysis with An. gambiae OBPs. The characterization of An. sinensis OBPs, including the motif's conservation, gene structure, genomic organization and classification, were investigated. A new gene, AsOBP73, belonging to the Plus-C subfamily, was identified with the support of transcript and conservative motifs. These An. sinensis OBP genes were classified into three subfamilies with 37, 15 and 12 genes in the subfamily Classic, Atypical and Plus-C, respectively. The genomic organization of An. sinensis OBPs suggests a clustered distribution across nine different scaffolds. Eight genes (OBP23-28, OBP63-64) might originate from a single gene through a series of historic duplication events at least before divergence of Anopheles, Culex and Aedes. The microsynteny analyses indicate a very high synteny between An. sinensis and An. gambiae OBPs. OBP70 and OBP71 earlier classified under Plus-C in An. gambiae are recognized as belonging to the group Obp59a of the Classic subfamily, and OBP69 earlier classified under Plus-C has been moved to the Atypical subfamily in this study. The study established a basic information frame for further study of the OBP genes in insects as well as in An. sinensis.
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Affiliation(s)
- Xiu He
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
| | - Zheng-Bo He
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
| | - Yu-Juan Zhang
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
| | - Yong Zhou
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
| | - Peng-Jie Xian
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
| | - Liang Qiao
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
| | - Bin Chen
- Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, 401331, China
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10
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Zhou J, Zhang N, Wang P, Zhang S, Li D, Liu K, Wang G, Wang X, Ai H. Identification of Host-Plant Volatiles and Characterization of Two Novel General Odorant-Binding Proteins from the Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae). PLoS One 2015; 10:e0141208. [PMID: 26517714 PMCID: PMC4627759 DOI: 10.1371/journal.pone.0141208] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 10/05/2015] [Indexed: 11/19/2022] Open
Abstract
Chemoreception is a key feature in selection of host plant by phytophagous insects, and odorant-binding proteins (OBPs) are involved in chemical communication of both insects and vertebrates. The legume pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) is one of the key pest species of cowpea and widely distributed throughout tropical and subtropical regions, causing up to 80% of yield loss. In this study, we investigated the electrophysiological responses of female M. vitrata to floral volatiles from V. unguiculata. Seventeen electroantennogram-active compounds were identified from floral volatiles of V. unguiculata by coupled gas chromatography-electroantennography (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). Then, we cloned two novel full-length GOBP genes (MvitGOBP1 and MvitGOBP2) from the antennae of M. vitrata using reverse transcription PCR. Protein sequence analysis indicated that they shared high sequence similarity with other Pyralididae insect GOBPs and had the typical six-cysteine signature. Real-time PCR analysis indicated that MvitGOBP1-2 mRNA was highly expressed in the antennae of female adult with several thousands-fold difference compare to other tissue. Next, the recombinant MvitGOBP1-2 was expressed in Escherichia coli and purified using Ni ion affinity chromatography. Fluorescence binding assays demonstrated that MvitGOBP1-2 had different binding affinities with 17 volatile odorant molecules including butanoic acid butyl ester, limonene, 4-ethylpropiophenone, 1H-indol-4-ol, butanoic acid octyl ester and 2-methyl-3-phenylpropanal. In the field trapping experiment, these six floral volatiles could effectively attract female moths and showed significant difference compared with the blank lure. These results suggested that MvitGOBPs and the seventeen floral volatiles are likely to function in the olfactory behavior response of female moths, which may have played crucial roles in the selection of oviposition sites. The six compounds that we have identified from the volatiles of V. unguiculata may provide useful information for exploring efficiency monitoring and integrated pest management strategies of this legume pod borer in the field.
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Affiliation(s)
- Jing Zhou
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Na Zhang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Pan Wang
- Key Laboratory of Insect Resource Utilization & Sustainable Pest Management of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shichang Zhang
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Daiqin Li
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Kaiyu Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Guoxiu Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Xiaoping Wang
- Key Laboratory of Insect Resource Utilization & Sustainable Pest Management of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Hui Ai
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
- * E-mail:
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11
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Gholizadeh S, Firooziyan S, Ladonni H, Hajipirloo HM, Djadid ND, Hosseini A, Raz A. The Anopheles stephensi odorant binding protein 1 (AsteObp1) gene: a new molecular marker for biological forms diagnosis. Acta Trop 2015; 146:101-13. [PMID: 25795618 DOI: 10.1016/j.actatropica.2015.03.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 02/25/2015] [Accepted: 03/09/2015] [Indexed: 10/23/2022]
Abstract
Anopheles (Cellia) stephensi Liston 1901 is known as an Asian malaria vector. Three biological forms, namely "mysorensis", "intermediate", and "type" have been earlier reported in this species. Nevertheless, the present morphological and molecular information is insufficient to diagnose these forms. During this investigation, An. stephensi biological forms were morphologically identified and sequenced for odorant-binding protein 1 (Obp1) gene. Also, intron I sequences were used to construct phylogenetic trees. Despite nucleotide sequence variation in exon of AsteObp1, nearly 100% identity was observed at the amino acid level among the three biological forms. In order to overcome difficulties in using egg morphology characters, intron I sequences of An. stephensi Obp1 opens new molecular way to the identification of the main Asian malaria vector biological forms. However, multidisciplinary studies are needed to establish the taxonomic status of An. stephensi.
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12
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Molecular and functional characterization of odorant-binding protein genes in an invasive vector mosquito, Aedes albopictus. PLoS One 2013; 8:e68836. [PMID: 23935894 PMCID: PMC3720860 DOI: 10.1371/journal.pone.0068836] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 06/03/2013] [Indexed: 11/20/2022] Open
Abstract
Aedes albopictus is a major vector of dengue and Chikungunya viruses. Olfaction plays a vital role in guiding mosquito behaviors and contributes to their ability to transmit pathogens. Odorant-binding proteins (OBPs) are abundant in insect olfactory tissues and involved in the first step of odorant reception. While comprehensive descriptions are available of OBPs from Aedes aegypti, Culex quinquefasciatus and Anopheles gambiae, only a few genes from Ae. albopictus have been reported. In this study, twenty-one putative AalbOBP genes were cloned using their homologues in Ae. aegypti to query an Ae. albopictus partial genome sequence. Two antenna-specific OBPs, AalbOBP37 and AalbOBP39, display a remarkable similarity in their overall folding and binding pockets, according to molecular modeling. Binding affinity assays indicated that AalbOBP37 and AalbOBP39 had overlapping ligand affinities and are affected in different pH condition. Electroantennagrams (EAG) and behavioral tests show that these two genes were involved in olfactory reception. An improved understanding of the Ae. albopictus OBPs is expected to contribute to the development of more efficient and environmentally-friendly mosquito control strategies.
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13
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Gong L, Luo Q, Rizwan-ul-Haq M, Hu MY. Cloning and characterization of three chemosensory proteins from Spodoptera exigua and effects of gene silencing on female survival and reproduction. BULLETIN OF ENTOMOLOGICAL RESEARCH 2012; 102:600-609. [PMID: 22475511 DOI: 10.1017/s0007485312000168] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Insect chemosensory proteins (CSPs) are supposed to transport hydrophobic chemicals to receptors on sensory neurons. However, CSPs are broadly expressed in various insect tissues, suggesting their involvement in the physiological processes beyond chemoreception. So, the exact physiological roles of CSPs in insects still need to be unraveled. In this study, three full-length of CSP genes from Spodoptera exigua have been cloned and characterized. The deduced amino acid sequences of SexiCSP1, SexiCSP2 and SexiCSP3 revealed open reading frames of 128, 128 and 126 amino acids, respectively, with four conserved cysteine residues. The expression patterns of the three SexiCSPs were further investigated by real-time PCR. Three SexiCSPs were expressed in antennae, heads, legs, wings, thoraxes, abdomens, testes and ovaries, with the highest expression level in female and male antennae. Furthermore, all three SexiCSPs mRNA were distributed extensively in the tested development stages with the highest expression level in pupae. RNAi-based gene silencing study resulted in a dramatic reduction of corresponding mRNA in female S. exigua after injection with dsRNA of all three SexiCSPs. Consequentially, 42.5% of mortalities, 68.3% (compare to DEPC water injected control) and 71.4% (compare to uninjected control) oviposition inhibition, and significantly effected egg hatching were observed in the female S. exigua injected with dsSexiCSP3 as compared to control treatments. On the other hand, dsSexiCSP1 and dsSexiCSP2 injected female adults did not show effects on survival and reproduction. Our study confirms the utility of RNAi approach to functional characterization of CSP genes in S. exigua and provides a starting point for further studies on female survival and reproduction in this insect. It also reveals the potential pest controlling method, as insect behavior regulation agent that disrupts the expression of chemosensory proteins.
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Affiliation(s)
- L Gong
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, P.R. China, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, Guangdong Province, China
| | - Q Luo
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, P.R. China, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, Guangdong Province, China
| | - M Rizwan-ul-Haq
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, P.R. China, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, Guangdong Province, China
| | - M-Y Hu
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, P.R. China, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, Guangdong Province, China
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14
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Pelletier J, Leal WS. Characterization of olfactory genes in the antennae of the Southern house mosquito, Culex quinquefasciatus. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:915-929. [PMID: 21504749 DOI: 10.1016/j.jinsphys.2011.04.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 03/25/2011] [Accepted: 04/01/2011] [Indexed: 05/30/2023]
Abstract
Odorant reception in insects is mediated by different families of olfactory proteins. Here we focus on the characterization of odorant-binding proteins (OBPs), "plus-C" odorant-binding proteins ("plus-C" OBPs), chemosensory proteins (CSPs) and sensory neuron membrane proteins (SNMPs) families from the Southern house mosquito, Culex quinquefasciatus, a vector of pathogens implicated in multiple human diseases. Using bioinformatics and molecular approaches, we have identified a diversity of genes in the genome of Culex quinquefasciatus and examined their expression profiles by RT-PCR and real-time quantitative PCR. Based on their high transcript enrichment in female antennae compared to non-olfactory tissues, we have identified twelve OBPs, two "plus-C" OBPs and two SNMPs that likely play important roles in odorant reception. Transcripts of two genes were clearly enriched in female antennae compared to male antennae, whereas other genes displayed relatively equivalent transcript levels in antennae of both sexes. Additionally, eight genes were found to be transcribed at very high levels in female antennae compared to CquiOR7, suggesting they might encode highly abundant olfactory proteins. Comparative analysis across different mosquito species revealed that olfactory genes of Culex quinquefasciatus are related to putative orthologs in other species, indicating that they might perform similar functions. Understanding how mosquitoes are able to detect ecologically relevant odorant cues might help designing better control strategies. We have identified olfactory genes from different families which are likely important in Culex quinquefasciatus behaviors, thus paving the way towards a better understanding of the diversity of proteins involved in the reception of semiochemicals in this species.
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Affiliation(s)
- Julien Pelletier
- Honorary Maeda-Duffey Laboratory, Department of Entomology, University of California Davis, Davis, CA, USA.
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15
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Zhao L, Chen J, Becnel JJ, Kline DL, Clark GG, Linthicum KJ. Identification and transcription profiling of trypsin in Aedes taeniorhynchus (Diptera: Culicidae): developmental regulation, blood feeding, and permethrin exposure. JOURNAL OF MEDICAL ENTOMOLOGY 2011; 48:546-553. [PMID: 21661315 DOI: 10.1603/me10211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The cDNA of a trypsin gene from Aedes (Ochlerotatus) taeniorhynchus (Weidemann) was cloned and sequenced. The full-length mRNA sequence (890 bp) for trypsin from Ae. taeniorhynchus (AetTryp1) was obtained, which encodes an open reading frame of 765 bp (i.e., 255 amino acids). To detect whether AetTryp is developmentally regulated, a quantitative real-time polymerase chain reaction was used to examine AetTrypl mRNA expression levels in different developmental stages of Ae. taeniorhynchus. AetTryp1 was expressed at low levels in egg, larval, and pupal stages, but was differentially expressed in adult Ae. taeniorhynchus, with highest levels found in 5-d-old female adults when compared with teneral adults. In addition, AetTryp1 mRNA expression differed between sexes, with expression levels much lower in males. However, in both males and females, there was a significant increase in AetTryp1 transcription levels as age increased and peaked in 5-d-old adults. AetTrypl expressed in 5-d-old female Ae. taeniorhynchus significantly increased after 30 min postblood feeding compared with the control. The AetTryp1 mRNA expression in 5-d-old female Ae. taeniorhynchus was affected by different concentrations of permethrin.
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Affiliation(s)
- Liming Zhao
- Biological Control of Pests Research Unit, Mid-Southern Area-United States Department of Agriculture-Agricultural Research Service, 59 Lee Road, Stoneville, MS 38776, USA.
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16
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Crespo JG. A review of chemosensation and related behavior in aquatic insects. JOURNAL OF INSECT SCIENCE (ONLINE) 2011; 11:62. [PMID: 21864156 PMCID: PMC3281456 DOI: 10.1673/031.011.6201] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 09/13/2010] [Indexed: 05/31/2023]
Abstract
Insects that are secondarily adapted to aquatic environments are able to sense odors from a diverse array of sources. The antenna of these insects, as in all insects, is the main chemosensory structure and its input to the brain allows for integration of sensory information that ultimately ends in behavioral responses. Only a fraction of the aquatic insect orders have been studied with respect to their sensory biology and most of the work has centered either on the description of the different types of sensilla, or on the behavior of the insect as a whole. In this paper, the literature is exhaustively reviewed and ways in which antennal morphology, brain structure, and associated behavior can advance better understanding of the neurobiology involved in processing of chemosensory information are discussed. Moreover, the importance of studying such group of insects is stated, and at the same time it is shown that many interesting questions regarding olfactory processing can be addressed by looking into the changes that aquatic insects undergo when leaving their aquatic environment.
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Affiliation(s)
- José G Crespo
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA.
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17
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Xu W, Cornel AJ, Leal WS. Odorant-binding proteins of the malaria mosquito Anopheles funestus sensu stricto. PLoS One 2010; 5:e15403. [PMID: 21042539 PMCID: PMC2962654 DOI: 10.1371/journal.pone.0015403] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 09/20/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The mosquito Anopheles funestus is one of the major malaria vector species in sub-Saharan Africa. Olfaction is essential in guiding mosquito behaviors. Odorant-binding proteins (OBPs) are highly expressed in insect olfactory tissues and involved in the first step of odorant reception. An improved understanding of the function of malaria mosquito OBPs may contribute to identifying new attractants/repellents and assist in the development of more efficient and environmentally friendly mosquito controlling strategies. METHODOLOGY In this study, a large screening of over 50 ecologically significant odorant compounds led to the identification of 12 ligands that elicit significant electroantennographic (EAG) responses from An. funestus female antennae. To compare the absolute efficiency/potency of these chemicals, corrections were made for differences in volatility by determining the exact amount in a stimulus puff. Fourteen AfunOBP genes were cloned and their expression patterns were analyzed. AfunOBP1, 3, 7, 20 and 66 showed olfactory tissue specificity by reverse transcriptase PCR (RT-PCR). Quantitative real-time PCR (qRT-PCR) analysis showed that among olfactory-specific OBPs, AfunOBP1 and 3 are the most enriched OBPs in female antennae. Binding assay experiments showed that at pH 7, AfunOBP1 significantly binds to 2-undecanone, nonyl acetate, octyl acetate and 1-octen-3-ol but AfunOBP3, which shares 68% identify with AfunOBP1 at amino acid level, showed nearly no binding activity to the selected 12 EAG-active odorant compounds. CONCLUSION This work presents for the first time a study on the odorants and OBPs of the malaria vector mosquito An. funestus, which may provide insight into the An. funestus olfactory research, assist in a comparative study between major malaria mosquitoes An. gambiae and An. funestus olfactory system, and help developing new mosquito control strategies to reduce malaria transmission.
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Affiliation(s)
- Wei Xu
- Department of Entomology, University of California Davis, Davis, California, United States of America
| | - Anthony J. Cornel
- 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
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18
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Sengul MS, Tu Z. Expression analysis and knockdown of two antennal odorant-binding protein genes in Aedes aegypti. JOURNAL OF INSECT SCIENCE (ONLINE) 2010; 10:171. [PMID: 21062207 PMCID: PMC3016889 DOI: 10.1673/031.010.14131] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 10/22/2009] [Indexed: 05/30/2023]
Abstract
The presence and expression of odorant-binding proteins (OBPs) in the olfactory organs suggest that they play an important role in mosquito olfaction. However, no direct evidence has been found for their involvement in the host-seeking behavior of mosquitoes. It is important to establish a method in which a loss-of-function test can be performed to determine the possible role of these genes in olfaction. In this study, a double subgenomic Sindbis virus expression system was used to reduce the expression of two Obp genes in Aedes aegypti L (Diptera: Culicidae), AaegObp1 and AaegObp2. Quantitative real-time PCR analysis showed predominant expression of both genes in the female antennae, the primary olfactory tissue of mosquitoes. Moreover, at 11 days post virus-inoculation, the mRNA levels of AaegObp1 and AaegObp2 were significantly reduced in olfactory tissues of recombinant virus-inoculated female mosquitoes compared to that of controls by approximately 8 and 100-fold, respectively. These data suggest that the double subgenomic Sindbis virus expression system can be efficiently used to knockdown Obp gene expression in olfactory tissues of mosquitoes. We discuss the potential for a systematic analysis of the molecular players involved in mosquito olfaction using this newly developed technique. Such analysis will provide an important step to interfere with the host-seeking behavior of mosquitoes to prevent the transmission of diseases.
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Affiliation(s)
- Meryem S. Sengul
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
- Current address: Department of Biology, Bozok University, Yozgat, 66200, Turkey
| | - Zhijian Tu
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
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