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Xiao Y, Wu Y, Lei C, Yin F, Peng Z, Jing X, Zhang Y, Li Z. Ligand binding properties of three odorant-binding proteins in striped flea beetle Phyllotreta striolata towards two phthalate esters. INSECT MOLECULAR BIOLOGY 2024; 33:405-416. [PMID: 38478920 DOI: 10.1111/imb.12907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 03/04/2024] [Indexed: 07/10/2024]
Abstract
Odorant-binding proteins (OBPs) initiate insect olfactory perception and mediate specific binding and selection of odorants via uncertain binding mechanisms. We characterized the binding characteristics of four OBPs from the striped flea beetle Phyllotreta striolata (SFB), a major cruciferous crop pest. Tissue expression analysis revealed that the two ABPII OBPs (PstrOBP12 and PstrOBP19) were highly expressed mainly in the antenna, whereas the two minus-C OBPs (PstrOBP13 and PstrOBP16) showed a broad expression pattern. Competitive binding assays of cruciferous plant volatiles showed that PstrOBP12, PstrOBP16 and PstrOBP19 had very strong binding capacities for only two phthalate esters (Ki < 20 μM), and PstrOBP13 specifically bound to four aromatic volatiles (Ki < 11 μM). Fluorescence quenching assays displayed that two phthalate esters bound to three PstrOBPs via different quenching mechanisms. PstrOBP12/PstrOBP16-diisobutyl phthalate and PstrOBP19-bis(6-methylheptyl) phthalate followed static quenching, while PstrOBP12/PstrOBP16-bis(6-methylheptyl) phthalate and PstrOBP19-diisobutyl phthalate followed dynamic quenching. Homology modelling and molecular docking displayed that PstrOBP12-diisobutyl phthalate was driven by H-bonding and van der Waals interactions, while PstrOBP16-diisobutyl phthalate and PstrOBP19-bis(6-methylheptyl) phthalate followed hydrophobic interactions. Finally, behavioural activity analysis demonstrated that phthalate esters exhibited different behavioural activities of SFB at different doses, with low doses attracting and high doses repelling. Overall, we thus revealed the different binding properties of the three PstrOBPs to two phthalate esters, which was beneficial in shedding light on the ligand-binding mechanisms of OBPs.
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Affiliation(s)
- Yong Xiao
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, P.R. China
| | - Yuhong Wu
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, P.R. China
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, P.R. China
| | - Chunmei Lei
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, P.R. China
| | - Fei Yin
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, P.R. China
| | - Zhengke Peng
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, P.R. China
| | - Xiangfeng Jing
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, P.R. China
| | - Yongjun Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, P.R. China
| | - Zhenyu Li
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, P.R. China
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Zhang X, Purba ER, Sun J, Zhang QH, Dong SL, Zhang YN, He P, Mang D, Zhang L. Functional differentiation of two general-odorant binding proteins in Hyphantria cunea (Drury) (Lepidoptera: Erebidae). PEST MANAGEMENT SCIENCE 2023. [PMID: 37103977 DOI: 10.1002/ps.7515] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 03/21/2023] [Accepted: 04/27/2023] [Indexed: 05/20/2023]
Abstract
BACKGROUND General odor-binding proteins (GOBPs) play critical roles in insect olfactory recognition of sex pheromones and plant volatiles. Therefore, the identification of GOBPs in Hyphantria cunea (Drury) based on their characterization to pheromone components and plant volatiles is remain unknown. RESULTS In this study, two H. cunea (HcunGOBPs) genes were cloned, and their expression profiles and odorant binding characteristics were systematically analyzed. Firstly, the tissue expression study showed that both HcunGOBP1 and HcunGOBP2 were highly expressed in the antennae of both sexes, indicating their potential involvement in the perception of sex pheromones. Secondly, these two HcunGOBPs genes were expressed in Escherichia coli and ligand binding assays were used to assess the binding affinities to its sex pheromone components including two aldehydes and two epoxides, and some plant volatiles. HcunGOBP2 showed high binding affinities to two aldehyde components (Z9, Z12, Z15-18Ald and Z9, Z12-18Ald), and showed low binding affinities to two epoxide components (1, Z3, Z6-9S, 10R-epoxy-21Hy and Z3, Z6-9S, 10R-epoxy-21Hy), whereas HcunGOBP1 showed weak but significant binding to all four sex pheromone components. Furthermore, both HcunGOBPs demonstrated variable binding affinities to the plant volatiles tested. Thirdly, in silico studies of HcunGOBPs utilized homology, structure modeling, and molecular docking revealed critical hydrophobic residues might be involved in the binding of HcunGOBPs to their sex pheromone components and plant volatiles. CONCLUSION Our study suggests that these two HcunGOBPs may serve as potential targets for future studies of HcunGOBPs ligand binding, providing insight in the mechanism of olfaction in H. cunea. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Xiaoqing Zhang
- Anhui Provincial Key Laboratory of Microbial Control, Engineering Research Center of Fungal Biotechnology, Ministry of Education School of Forestry & Landscape Architecture, Anhui Agricultural University, Hefei, China
- Education Ministry, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Endang R Purba
- Structural Cellular Biology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Jing Sun
- College of Life Science, Hebei University, Baoding, China
| | | | - Shuang-Lin Dong
- Education Ministry, Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Ya-Nan Zhang
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Peng He
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, China
| | - Dingze Mang
- College of Life Science, Hebei University, Baoding, China
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Longwa Zhang
- Anhui Provincial Key Laboratory of Microbial Control, Engineering Research Center of Fungal Biotechnology, Ministry of Education School of Forestry & Landscape Architecture, Anhui Agricultural University, Hefei, China
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Song C, Ma L, Zhao J, Xue Z, Yan X, Hao C. Electrophysiological and Behavioral Responses of Plutella xylostella (Lepidoptera: Plutellidae) to Volatiles from a Non-host Plant, Geranium, Pelargonium × hortorum (Geraniaceae). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:5982-5992. [PMID: 35576618 DOI: 10.1021/acs.jafc.1c08165] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The diamondback moth (DBM), Plutella xylostella (Lepidoptera: Plutellidae), is a notorious cruciferous vegetable pest globally. Mechanically damaged geranium (Pelargonium × hortorum) can strongly repel DBM, but specific plant bioactive compounds responsible for such effects have not been identified. The headspace volatiles from wounded geranium were analyzed using gas chromatography-electroantennographic detection and gas chromatography-mass spectrometry. The electrophysiological and behavioral responses of DBM females to these chemicals and two blends were investigated. The results showed that five components myrcene, γ-terpinene, linalool, camphor, and terpinen-4-ol in geranium plants mediated the repellence of DBM mated females. These substances significantly repelled the oviposition of females, and blend-2 (a mixture of the five components with a ratio 1:5:3:4:3) was most effective. The slow-release blend-2 had a repellent range of 0.9 m and a repellent longevity of 26 days. These five substances are promising behavioral regulators of the destructive moths and could be potential candidates for "push" components in plant-based "push-pull" strategies.
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Affiliation(s)
- Chengfei Song
- College of Plant Protection, Shanxi Agricultural University, Taigu 030801, PR China
| | - Li Ma
- College of Plant Protection, Shanxi Agricultural University, Taigu 030801, PR China
| | - Jinyu Zhao
- College of Plant Protection, Shanxi Agricultural University, Taigu 030801, PR China
| | - Zengsheng Xue
- College of Plant Protection, Shanxi Agricultural University, Taigu 030801, PR China
| | - Xizhong Yan
- College of Plant Protection, Shanxi Agricultural University, Taigu 030801, PR China
| | - Chi Hao
- College of Plant Protection, Shanxi Agricultural University, Taigu 030801, PR 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: 0.3] [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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Younas A, Waris MI, Shaaban M, Tahir Ul Qamar M, Wang MQ. Appraisal of MsepCSP14 for chemosensory functions in Mythimna separata. INSECT SCIENCE 2022; 29:162-176. [PMID: 33822484 DOI: 10.1111/1744-7917.12909] [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: 04/30/2020] [Revised: 01/31/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
Chemosensory proteins (CSPs) have great contributions in performing diverse functions in insects. However, physiological appraisal of chemosensory protein genes still remains elusive in insects. We studied expression patterns and binding affinities of MsepCSP14, a chemosensory protein, in Mythimna separata. The distinct functions of MsepCSP14 were validated by employing different molecular techniques. The MsepCSP14 had high resemblance of sequence with chemosensory proteins of other insect family members. The MsepCSP14 expression was higher in antennal tissues of females than other tissues. Fluorescence binding assay validated that binding of nine out of 21 ligands to MsepCSP14 was higher at pH 7.4 than at pH 5.0. Three dimensional modeling (3D) and docking analysis predicted that amino acid residues of MsepCSP14 were involved in binding of compounds, and behavior assay displayed that adults of M. separata considerably responded to four volatiles from compounds demonstrating strong binding ability to MsepCSP14. Results of the present study suggest that MsepCSP14 is likely to mediate chemosensory functions in M. separata.
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Affiliation(s)
- Aneela Younas
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Muhammad Irfan Waris
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Muhammad Shaaban
- Department of Soil Science, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| | - Muhammad Tahir Ul Qamar
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, 530005, China
| | - Man-Qun Wang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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GOBP1 from the Variegated Cutworm Peridroma saucia (Hübner) (Lepidoptera: Noctuidae) Displays High Binding Affinities to the Behavioral Attractant ( Z)-3-Hexenyl acetate. INSECTS 2021; 12:insects12100939. [PMID: 34680708 PMCID: PMC8540349 DOI: 10.3390/insects12100939] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/10/2021] [Accepted: 10/11/2021] [Indexed: 11/17/2022]
Abstract
The variegated cutworm Peridroma saucia (Hübner) is a worldwide pest that causes serious damage to many crops. To recognize sex pheromones and host plant volatiles, insects depend on olfactory chemoreception involving general odorant-binding proteins (GOBPs). In this study, PsauGOBP1 was cloned from the adult antennae of P. saucia. RT-qPCR and Western-blot analysis showed that PsauGOBP1 was specifically and equally expressed in the adult antennae of both females and males. Fluorescence competitive-binding assays with sex pheromones and host plant volatiles demonstrated that PsauGOBP1 bound to six host plant volatiles: (Z)-3-hexenyl acetate (KD = 4.0 ± 0.1 μM), citral (KD = 5.6 ± 0.4 μM), farnesol (KD = 6.4 ± 0.6 μM), nonanal (KD = 6.8 ± 0.3 μM), (Z)-3-hexen-1-ol (KD = 8.5 ± 0.6 μM), and benzaldehyde (KD = 9.4 ± 0.5 μM). Electroantennogram recordings with the six host plant volatiles indicated that (Z)-3-hexenyl acetate elicited the strongest responses from both male and female antennae. Further bioassays using Y-tube olfactometers showed that (Z)-3-hexenyl acetate was attractive to adult P. saucia of both sexes. These results suggest that PsauGOBP1 might be involved in detecting host plant volatiles and that (Z)-3-hexenyl acetate might serve as a potential attractant for the biological control of P. saucia.
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Huang C, Zhang X, He D, Wu Q, Tang R, Xing L, Liu W, Wang W, Liu B, Xi Y, Yang N, Wan F, Qian W. Comparative Genomics Provide Insights Into Function and Evolution of Odorant Binding Proteins in Cydia pomonella. Front Physiol 2021; 12:690185. [PMID: 34305643 PMCID: PMC8294088 DOI: 10.3389/fphys.2021.690185] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/15/2021] [Indexed: 11/13/2022] Open
Abstract
Insect olfaction is vital for foraging, mating, host-seeking, and avoidance of predators/pathogens. In insects, odorant binding proteins (OBPs) are involved in transporting hydrophobic odor molecules from the external environment to receptor neurons. The codling moth, Cydia pomonella, one of the most destructive insect fruit pests, causes enormous economic losses. However, little is known about the number, variety, gains and losses, and evolution of OBP genes in C. pomonella. Here we report the identification of 40 OBPs in C. pomonella, most (75%) of which are classic OBPs, using genomic and transcriptomic analyses. Two OBP genes were lost in C. pomonella relative to possible distant ancestor in Lepidoptera lineage based on an analysis of gene gains and losses. The phylogenetic tree and chromosome location showed that the expansion of OBP genes mainly resulted from tandem duplications, as the CpomGOBP2 gene was duplicated twice along with loss of CpomPBPB. Two positive selection sites of the CpomGOBP1 gene were identified while other OBP genes evolved under purifying selection. Our results provide fundamental knowledge of OBP genes allowing further study of their function in C. pomonella.
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Affiliation(s)
- Cong Huang
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Xue Zhang
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Dongfeng He
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
- Hubei Engineering Research Center for Pest Forewarning and Management, Yangtze University, Jingzhou, China
| | - Qiang Wu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Rui Tang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Longsheng Xing
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Wanxue Liu
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wenkai Wang
- Hubei Engineering Research Center for Pest Forewarning and Management, Yangtze University, Jingzhou, China
| | - Bo Liu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yu Xi
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Nianwan Yang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fanghao Wan
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wanqiang Qian
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
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Li L, Zhang WB, Shan YM, Zhang ZR, Pang BP. Functional Characterization of Olfactory Proteins Involved in Chemoreception of Galeruca daurica. Front Physiol 2021; 12:678698. [PMID: 34177623 PMCID: PMC8221581 DOI: 10.3389/fphys.2021.678698] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/29/2021] [Indexed: 11/13/2022] Open
Abstract
Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) play a fundamental role in insect olfaction. Galeruca daurica (Joannis) is a new pest with outbreak status in the Inner Mongolia grasslands, northern China. In this study, six olfactory protein genes (GdauOBP1, GdauOBP6, GdauOBP10, GdauOBP15, GdauCSP4, and GdauCSP5) were cloned by RACE and expressed by constructing a prokaryotic expression system. Their binding affinities to 13 compounds from host volatiles (Allium mongolicum) were determined by fluorescence-binding assay. In order to further explore the olfactory functions of GdauOBP15 and GdauCSP5, RNA interference (RNAi) and electroantennogram (EAG) experiments were conducted. Ligand-binding assays showed that the binding properties of the six recombinant proteins to the tested volatiles were different. GdauOBP6, GdauOBP15, GdauCSP4, and GdauCSP5 could bind several tested ligands of host plants. It was suspected that GdauOBP6, GdauOBP15, GdauCSP4, and GdauCSP5 were related to the host location in G. daurica. We also found that there were different EAG responses between males and females when the GdauOBP15 and GdauCSP5 genes were silenced by RNAi. The EAG response of G. daurica females to 2-hexenal was significantly decreased in dsRNA-OBP15-injected treatment compared to the control, and the dsRNA-CSP5-treated females significantly reduced EAG response to eight tested host volatiles (1,3-dithiane, 2-hexenal, methyl benzoate, dimethyl trisulfide, myrcene, hexanal, 1,3,5-cycloheptatriene, and p-xylene). However, the EAG response had no significant difference in males. Both GdauOBP15 and GdauCSP5 may have different functions between males and females in G. daurica and may play more important roles in females searching for host plants.
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Affiliation(s)
- Ling Li
- Research Center for Grassland Entomology, Inner Mongolia Agricultural University, Hohhot, China
| | - Wen-Bing Zhang
- Research Center for Grassland Entomology, Inner Mongolia Agricultural University, Hohhot, China
| | - Yan-Min Shan
- Inner Mongolia Forestry and Grassland Pest Control and Quarantine Station, Hohhot, China
| | - Zhuo-Ran Zhang
- Inner Mongolia Forestry and Grassland Pest Control and Quarantine Station, Hohhot, China
| | - Bao-Ping Pang
- Research Center for Grassland Entomology, Inner Mongolia Agricultural University, Hohhot, China
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