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Korona D, Dirnberger B, Giachello CNG, Queiroz RML, Popovic R, Müller KH, Minde DP, Deery MJ, Johnson G, Firth LC, Earley FG, Russell S, Lilley KS. Drosophila nicotinic acetylcholine receptor subunits and their native interactions with insecticidal peptide toxins. eLife 2022; 11:74322. [PMID: 35575460 PMCID: PMC9110030 DOI: 10.7554/elife.74322] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 04/19/2022] [Indexed: 12/14/2022] Open
Abstract
Drosophila nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that represent a target for insecticides. Peptide neurotoxins are known to block nAChRs by binding to their target subunits, however, a better understanding of this mechanism is needed for effective insecticide design. To facilitate the analysis of nAChRs we used a CRISPR/Cas9 strategy to generate null alleles for all ten nAChR subunit genes in a common genetic background. We studied interactions of nAChR subunits with peptide neurotoxins by larval injections and styrene maleic acid lipid particles (SMALPs) pull-down assays. For the null alleles, we determined the effects of α-Bungarotoxin (α-Btx) and ω-Hexatoxin-Hv1a (Hv1a) administration, identifying potential receptor subunits implicated in the binding of these toxins. We employed pull-down assays to confirm α-Btx interactions with the Drosophila α5 (Dα5), Dα6, Dα7 subunits. Finally, we report the localisation of fluorescent tagged endogenous Dα6 during Drosophila CNS development. Taken together, this study elucidates native Drosophila nAChR subunit interactions with insecticidal peptide toxins and provides a resource for the in vivo analysis of insect nAChRs.
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Affiliation(s)
- Dagmara Korona
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, United Kingdom
| | - Benedict Dirnberger
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, United Kingdom.,Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom.,Syngenta, Jealott's Hill International Research Centre, Bracknell, United Kingdom
| | - Carlo N G Giachello
- Syngenta, Jealott's Hill International Research Centre, Bracknell, United Kingdom
| | - Rayner M L Queiroz
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Rebeka Popovic
- MRC Toxicology Unit, Gleeson Building, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
| | - Karin H Müller
- Cambridge Advanced Imaging Centre, Department of Physiology, Development and Neuroscience/Anatomy Building, University of Cambridge, Cambridge, United Kingdom
| | - David-Paul Minde
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Michael J Deery
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Glynnis Johnson
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, United Kingdom
| | - Lucy C Firth
- Syngenta, Jealott's Hill International Research Centre, Bracknell, United Kingdom
| | - Fergus G Earley
- Syngenta, Jealott's Hill International Research Centre, Bracknell, United Kingdom
| | - Steven Russell
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, United Kingdom
| | - Kathryn S Lilley
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
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Boonyos P, Trakulnalueamsai C, Rungrod A, Chongthammakun S, Promdonkoy B. Antagonistic Effect of Truncated Fragments of Bacillus thuringiensis Vip3Aa on the Larvicidal Activity of its Full-length Protein. Protein Pept Lett 2021; 28:131-139. [PMID: 32586243 DOI: 10.2174/0929866527666200625205846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/19/2020] [Accepted: 06/28/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Vip3Aa is a vegetative insecticidal protein produced by Bacillus thuringiensis. The protein is produced as an 88-kDa protoxin that could be processed by insect gut proteases into a 22-kDa N-terminal and a 66-kDa C-terminal fragments. The C-terminal part could bind to a specific receptor while the N-terminal part is required for toxicity and structural stability. OBJECTIVE To demonstrate the antagonistic effect of truncated fragments on the insecticidal activity of the full-length Vip3Aa. METHODS The full-length protein (Vip3Aa), a 66-kDa C-terminal fragment (Vip3Aa-D199) and a predicted carbohydrate binding module (CBM) were produced in Escherichia coli. Purified proteins were mixed at different ratios and fed to Spodoptera litura and Spodoptera exigua larvae. Mortality was recorded and compared between larvae fed with individual toxin and mixtures of the full-length and truncated toxins. RESULTS Production level of the Vip3Aa-D199 was significantly decreased comparing to that of the full-length protein. Vip3Aa-D199 and CBM fragment were not toxic to insect larvae whereas Vip3Aa showed high toxicity with LC50 about 200 ng/cm2. Feeding the larvae with mixtures of the Vip3Aa and Vip3Aa-D199 at different ratios revealed antagonistic effect of the Vip3Aa-D199 on the toxicity of Vip3Aa. Results showed that the lethal time (LT 50 and LT 95) of larvae fed the mixture toxins was longer than those fed the Vip3Aa alone. In addition, a CBM fragment could inhibit toxicity of the full-length Vip3Aa. CONCLUSION Our results demonstrated that the Vip3Aa-D199 and a CBM fragment could complete for the membrane binding thus rendering activity of the full-length Vip3Aa.
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Affiliation(s)
- Patcharaporn Boonyos
- Graduate Program in Molecular Medicine, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand
| | - Chutchanun Trakulnalueamsai
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand
| | - Amporn Rungrod
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand
| | - Sukumal Chongthammakun
- Graduate Program in Molecular Medicine, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand
| | - Boonhiang Promdonkoy
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand
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3
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Oliveira AC, Wanderley-Teixeira V, Silva CT, Teixeira ÁA, Siqueira HA, Cruz GS, Neto CJCL, Lima AL, Correia MT. Labeling membrane receptors with lectins and evaluation of the midgut histochemistry of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) populations with different levels of susceptibility to formulated Bt. PEST MANAGEMENT SCIENCE 2018; 74:2608-2617. [PMID: 29700928 DOI: 10.1002/ps.5051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 03/21/2018] [Accepted: 04/20/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Studies show that insects can adapt to the toxins of Bacillus thuringiensis under field and laboratory conditions through the development of resistance to the bacterium and its formulations. This has been demonstrated in the failure to control Tuta absoluta populations in Brazil. This study evaluated membrane receptors using peroxidase-labeled lectins and the midgut histochemistry of T. absoluta populations to assess susceptibility to the insecticides Bt fomulations. The histochemistry analysis used Periodic Acid-Schiff for glycogen and Ponceau Xylidine for total proteins. The presence of glucose/mannose and N-acetylgalactosamine (GalNAc) was analyzed using specific lectins. One susceptible and one tolerant population were used in the study; insects were exposed to the insecticide concentrations recommended by the manufacturers. The midgut was collected after an interval of 20 min and analyzed using optical microscopy. RESULTS Bt fomulation interferes with the glycogen content, whereas XenTari® interferes with the protein content, irrespective of the level of susceptibility. High expression of GalNAc residues was observed using soybean lectin labeling, indicating a direct relationship between the glycosylation pattern and susceptibility to Bt fomulation in the Pelotas population. CONCLUSION The use of Bt fomulation caused greater alterations in the larval intestinal histophysiology compared to the use of XenTari® . © 2018 Society of Chemical Industry.
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Affiliation(s)
- Andresa Cb Oliveira
- Department of Agronomy-Entomology, Federal Rural University of Pernambuco, Recife, Brazil
| | | | - Cristiane Ts Silva
- Department of Agronomy-Entomology, Federal Rural University of Pernambuco, Recife, Brazil
| | - Álvaro Ac Teixeira
- Department of Animal Morphology and Physiology, Federal Rural University of Pernambuco, Recife, Brazil
| | - Herbert Aa Siqueira
- Department of Agronomy-Entomology, Federal Rural University of Pernambuco, Recife, Brazil
| | - Glauciane S Cruz
- Department of Agronomy-Entomology, Federal Rural University of Pernambuco, Recife, Brazil
| | - Clovis J C Lapa Neto
- Department of Animal Morphology and Physiology, Federal Rural University of Pernambuco, Recife, Brazil
| | - Amanda Lr Lima
- Departament of Biochemistry, Federal University of Pernambuco, Recife, Brazil
| | - Maria Ts Correia
- Departament of Biochemistry, Federal University of Pernambuco, Recife, Brazil
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Walski T, De Schutter K, Cappelle K, Van Damme EJM, Smagghe G. Distribution of Glycan Motifs at the Surface of Midgut Cells in the Cotton Leafworm ( Spodoptera littoralis) Demonstrated by Lectin Binding. Front Physiol 2017; 8:1020. [PMID: 29276491 PMCID: PMC5727093 DOI: 10.3389/fphys.2017.01020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 11/24/2017] [Indexed: 01/06/2023] Open
Abstract
Glycans are involved in many biological phenomena, including signal transduction, cell adhesion, immune response or differentiation. Although a few papers have reported on the role of glycans in the development and proper functioning of the insect midgut, no data are available regarding the localization of the glycan structures on the surface of the cells in the gut of insects. In this paper, we analyzed the spatial distribution of glycans present on the surface of the midgut cells in larvae of the cotton leafworm Spodoptera littoralis, an important agricultural pest insect worldwide. For this purpose, we established primary midgut cell cultures, probed these individual cells that are freely suspended in liquid medium with a selection of seven fluorescently labeled lectins covering a range of different carbohydrate binding specificities [mannose oligomers (GNA and HHA), GalNAc/Gal (RSA and SSA), GlcNAc (WGA and Nictaba) and Neu5Ac(α-2,6)Gal/GalNAc (SNA-I)], and visualized the interaction of these lectins with the different zones of the midgut cells using confocal microscopy. Our analysis focused on the typical differentiated columnar cells with a microvillar brush border at their apical side, which are dominantly present in the Lepidopteran midgut and function in food digestion and absorption, and as well as on the undifferentiated stem cells that are important for midgut development and repair. Confocal microscopy analyses showed that the GalNAc/Gal-binding lectins SSA and RSA and the terminal GlcNAc-recognizing WGA bound preferentially to the apical microvillar zone of the differentiated columnar cells as compared to the basolateral pole. The reverse result was observed for the mannose-binding lectins GNA and HHA, as well as Nictaba that binds preferentially to GlcNAc oligomers. Furthermore, differences in lectin binding to the basal and lateral zones of the cell membranes of the columnar cells were apparent. In the midgut stem cells, GNA and Nictaba bound more strongly to the membrane of these undifferentiated cells compared to the microvillar pole of the columnar cells, while SSA, HHA, WGA, and SNA-I showed stronger binding to the microvilli. Our results indicated that polarization of the midgut cells is also reflected by a specific distribution of glycans, especially between the basal and microvillar pole. The data are discussed in relation to the functioning and development of the insect midgut.
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Affiliation(s)
- Tomasz Walski
- Department of Crop Protection, Ghent University, Ghent, Belgium.,Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | | | - Kaat Cappelle
- Department of Crop Protection, Ghent University, Ghent, Belgium
| | - Els J M Van Damme
- Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | - Guy Smagghe
- Department of Crop Protection, Ghent University, Ghent, Belgium
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5
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Holotrichia oblita Midgut Proteins That Bind to Bacillus thuringiensis Cry8-Like Toxin and Assembly of the H. oblita Midgut Tissue Transcriptome. Appl Environ Microbiol 2017; 83:AEM.00541-17. [PMID: 28389549 DOI: 10.1128/aem.00541-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 03/31/2017] [Indexed: 11/20/2022] Open
Abstract
The Bacillus thuringiensis strain HBF-18 (CGMCC 2070), containing two cry genes (cry8-like and cry8Ga), is toxic to Holotrichia oblita larvae. Both Cry8-like and Cry8Ga proteins are active against this insect pest, and Cry8-like is more toxic. To analyze the characteristics of the binding of Cry8-like and Cry8Ga proteins to brush border membrane vesicles (BBMVs) in H. oblita larvae, binding assays were conducted with a fluorescent DyLight488-labeled Cry8-like toxin. The results of saturation binding assays demonstrated that Cry8-like bound specifically to binding sites on BBMVs from H. oblita, and heterologous competition assays revealed that Cry8Ga shared binding sites with Cry8-like. Furthermore, Cry8-like-binding proteins in the midgut from H. oblita larvae were identified by pulldown assays and liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, the H. oblita midgut transcriptome was assembled by high-throughput RNA sequencing and used for identification of Cry8-like-binding proteins. Eight Cry8-like-binding proteins were obtained from pulldown assays conducted with BBMVs. The LC-MS/MS data for these proteins were successfully matched with the H. oblita transcriptome, and BLASTX results identified five proteins as serine protease, transferrin-like, uncharacterized protein LOC658236 of Tribolium castaneum, ATPase catalytic subunit, and actin. These identified Cry8-like-binding proteins were different from those confirmed previously as receptors for Cry1A proteins in lepidopteran insect species, such as aminopeptidase, alkaline phosphatase, and cadherin.IMPORTANCEHolotrichia oblita is one of the main soil-dwelling pests in China. The larvae damage the roots of crops, resulting in significant yield reductions and economic losses. H. oblita is difficult to control, principally due to its soil-dwelling habits. In recent years, some Cry8 toxins from Bacillus thuringiensis were shown to be active against this pest. Study of the mechanism of action of these Cry8 toxins is needed for their effective use in the control of H. oblita and for their future utilization in transgenic plants. Our work provides important basic data and promotes understanding of the insecticidal mechanism of Cry8 proteins against H. oblita larvae.
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Wang XY, Du LX, Liu CX, Gong L, Han LZ, Peng YF. RNAi in the striped stem borer, Chilo suppressalis, establishes a functional role for aminopeptidase N in Cry1Ab intoxication. J Invertebr Pathol 2016; 143:1-10. [PMID: 27823898 DOI: 10.1016/j.jip.2016.11.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 10/26/2016] [Accepted: 11/03/2016] [Indexed: 10/20/2022]
Abstract
The striped stem borer, Chilo suppressalis, is a major target pest of transgenic rice expressing the Cry1Ab protein from the bacterium Bacillus thuringiensis (Bt) in China. Evolution of resistance in this pest is a major threat to the durability of Bt rice. Since Bt exerts its activity through binding to specific receptors in the midgut of target insects, identification of functional Cry1Ab receptors in the midgut of C. suppressalis larvae is crucial to evaluate potential resistance mechanisms and develop effective strategies for delaying insect resistance. In this work, we identified the putative Cry1Ab toxin-binding protein, aminopeptidase-N (APN), in the midgut of C. suppressalis by ligand blot and mass spectrometry. After cloning the full-length cDNAs encoding APN isoforms from the C. suppressalis larval midgut, we studied their spatiotemporal expression in different gut tissues and developmental stages. Furthermore, RNA interference (RNAi) against C. suppressalis aminopeptidases (CsAPNs) was employed to illustrate a functional role for CsAPNs in Cry1Ab toxicity to C. suppressalis larvae using injection and oral delivery of Stealth™ siRNA. Down-regulating the expression of CsAPNs by RNAi was closely associated with reduced susceptibility of C. suppressalis to Cry1Ab. These data provide the first direct evidence that CsAPNs participate in the mode of Cry1Ab action and may act as the functional receptor of Cry1A in C. suppressalis larvae.
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Affiliation(s)
- X Y Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - L X Du
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - C X Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - L Gong
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - L Z Han
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Y F Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Feng M, He Z, Wang Y, Yan X, Zhang J, Hu Z, Wu W. Isolation of the Binding Protein of Periplocoside E from BBMVs in Midgut of the Oriental Amyworm Mythimna separata Walker (Lepidoptera: Noctuidae) through Affinity Chromatography. Toxins (Basel) 2016; 8:E139. [PMID: 27153092 PMCID: PMC4885054 DOI: 10.3390/toxins8050139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 04/26/2016] [Accepted: 04/27/2016] [Indexed: 11/16/2022] Open
Abstract
Periplocosides, which are insecticidal compounds isolated from the root bark of Periploca sepium Bunge, can affect the digestive system of insects. However, the mechanism though which periplocosides induces a series of symptoms remains unknown. In this study, affinity chromatography was conducted by coupling periplocoside E-semi-succinic acid ester with epoxy amino hexyl (EAH) sepharose 4B. Sodium dodecyl sulfonate-polyacrylamide gelelectrophoresis (SDS-PAGE) was performed to analyze the fraction eluted by periplocoside E. Eight binding proteins (luciferin 4-monooxygenase, aminopeptidase N, aminopeptidase N3, nicotinamide adenine dinucleotide health (NADH) dehydrogenase subunit 5, phosphatidylinositol 3-phosphate 3-phosphatase myotubularin, actin, uncharacterized family 31 glucosidase KIAA1161, and 2OG-Fe(2) oxygenase superfamily protein) were obtained and identified through liquid chromatography/quadrupole-time of flight-mass spectrometry (LC/Q-TOF-MS) analysis of the midgut epithelium cells of Mythimna separata larvae. Aminopeptidase N and N3 are potential putative targets of periplocosides. This study establishes the foundation for further research on the mechanism of action and target localization of periplocosides in agricultural pests.
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Affiliation(s)
- Mingxing Feng
- Key Laboratory of Botanical Pesticide R & D in Shaanxi Province, Yangling 712100, Shaanxi, China.
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Zhenyu He
- Key Laboratory of Botanical Pesticide R & D in Shaanxi Province, Yangling 712100, Shaanxi, China.
| | - Yuanyuan Wang
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Xiufang Yan
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Jiwen Zhang
- Key Laboratory of Botanical Pesticide R & D in Shaanxi Province, Yangling 712100, Shaanxi, China.
| | - Zhaonong Hu
- Key Laboratory of Botanical Pesticide R & D in Shaanxi Province, Yangling 712100, Shaanxi, China.
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Wenjun Wu
- Key Laboratory of Botanical Pesticide R & D in Shaanxi Province, Yangling 712100, Shaanxi, China.
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
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Shu C, Tan S, Yin J, Soberón M, Bravo A, Liu C, Geng L, Song F, Li K, Zhang J. Assembling of Holotrichia parallela (dark black chafer) midgut tissue transcriptome and identification of midgut proteins that bind to Cry8Ea toxin from Bacillus thuringiensis. Appl Microbiol Biotechnol 2015; 99:7209-18. [PMID: 26135984 DOI: 10.1007/s00253-015-6755-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 05/31/2015] [Accepted: 06/04/2015] [Indexed: 12/21/2022]
Abstract
Holotrichia parallela is one of the most severe crop pests in China, affecting peanut, soybean, and sweet potato crops. Previous work showed that Cry8Ea toxin is highly effective against this insect. In order to identify Cry8Ea-binding proteins in the midgut cells of H. parallela larvae, we assembled a midgut tissue transcriptome by high-throughput sequencing and used this assembled transcriptome to identify Cry8Ea-binding proteins by liquid chromatography-tandem mass spectrometry (LC-MS/MS). First, we obtained de novo sequences of cDNAs from midgut tissue of H. parallela larvae and used available cDNA data in the GenBank. In a parallel assay, we obtained 11 Cry8Ea-binding proteins by pull-down assays performed with midgut brush border membrane vesicles. Peptide sequences from these proteins were matched to the H. parallela newly assembled midgut transcriptome, and 10 proteins were identified. Some of the proteins were shown to be intracellular proteins forming part of the cell cytoskeleton and/or vesicle transport such as actin, myosin, clathrin, dynein, and tubulin among others. In addition, an apolipophorin, which is a protein involved in lipid metabolism, and a novel membrane-bound alanyl aminopeptidase were identified. Our results suggest that Cry8Ea-binding proteins could be different from those characterized for Cry1A toxins in lepidopteran insects.
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Affiliation(s)
- Changlong Shu
- State Key Laboratory of Biology for Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
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9
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Lu L, Qi Z, Zhang J, Wu W. Separation of Binding Protein of Celangulin V from the Midgut of Mythimna separata Walker by Affinity Chromatography. Toxins (Basel) 2015; 7:1738-48. [PMID: 25996604 PMCID: PMC4448171 DOI: 10.3390/toxins7051738] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 04/23/2015] [Accepted: 04/28/2015] [Indexed: 11/23/2022] Open
Abstract
Celangulin V, an insecticidal compound isolated from the root bark of Chinese bittersweet, can affect the digestive system of insects. However, the mechanism of how Celangulin V induces a series of symptoms is still unknown. In this study, affinity chromatography was conducted through coupling of Celangulin V-6-aminoacetic acid ester to the CNBr-activated Sepharose 4B. SDS-PAGE was used to analyze the collected fraction eluted by Celangulin V. Eight binding proteins (Zinc finger protein, Thioredoxin peroxidase (TPx), Glyceraldehyde 3-phosphate dehydrogenase (GAPDH), SUMO E3 ligase RanBP2, Transmembrane protein 1, Actin, APN and V-ATPase) were obtained and identified by LC/Q-TOF-MS from the midgut of Mythimna separata larvae. The potential of these proteins to serve as target proteins involved in the insecticidal activity of Celangulin V is discussed.
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Affiliation(s)
- Lina Lu
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Zhijun Qi
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Jiwen Zhang
- College of Science, Northwest A & F University, Yangling 712100, Shaanxi, China.
| | - Wenjun Wu
- Institute of Pesticide Science, College of Plant Protection, Northwest A & F University, Yangling 712100, Shaanxi, China.
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10
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Aroonkesorn A, Pootanakit K, Katzenmeier G, Angsuthanasombat C. Two specific membrane-bound aminopeptidase N isoforms from Aedes aegypti larvae serve as functional receptors for the Bacillus thuringiensis Cry4Ba toxin implicating counterpart specificity. Biochem Biophys Res Commun 2015; 461:300-6. [PMID: 25871797 PMCID: PMC7124302 DOI: 10.1016/j.bbrc.2015.04.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 04/05/2015] [Indexed: 12/28/2022]
Abstract
The interaction between Bacillus thuringiensis Cry toxins and their receptors on midgut cells of susceptible insect larvae is the critical determinant in toxin specificity. Besides GPI-linked alkaline phosphatase in Aedes aegypti mosquito-larval midguts, membrane-bound aminopeptidase N (AaeAPN) is widely thought to serve as a Cry4Ba receptor. Here, two full-length AaeAPN isoforms, AaeAPN2778 and AaeAPN2783, predicted to be GPI-linked were cloned and successfully expressed in Spodoptera frugiperda (Sf9) cells as 112- and 107-kDa membrane-bound proteins, respectively. In the cytotoxicity assay, Sf9 cells expressing each of the two AaeAPN isoforms showed increased sensitivity to the Cry4Ba mosquito-active toxin. Double immunolocalization revealed specific binding of Cry4Ba to each individual AaeAPN expressed on the cell membrane surface. Sequence analysis and homology-based modeling placed these two AaeAPNs to the M1 aminopeptidase family as they showed similar four-domain structures, with the most conserved domain II being the catalytic component. Additionally, the most variable domain IV containing negatively charged surface patches observed only in dipteran APNs could be involved in insect specificity. Overall results demonstrated that these two membrane-bound APN isoforms were responsible for mediating Cry4Ba toxicity against AaeAPN-expressed Sf9 cells, suggesting their important role as functional receptors for the toxin counterpart in A. aegypti mosquito larvae. Two novel Aedes GPI-APN isoforms were functionally expressed in Sf9 cells. Cells expressing each AaeAPN were more sensitive to Cry4Ba toxin cytolysis. Specific binding of Cry4Ba to individual AaeAPN-expressing Sf9 cells was demonstrated. These two AaeAPNs mediating Cry4Ba cytotoxicity serve as receptors in Aedes larvae. AaeAPN models reveal four-domain organization with implications for toxin-counterpart specificity.
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Affiliation(s)
- Aratee Aroonkesorn
- Bacterial Protein Toxin Research Cluster, Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand
| | - Kusol Pootanakit
- Bacterial Protein Toxin Research Cluster, Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand
| | - Gerd Katzenmeier
- Bacterial Protein Toxin Research Cluster, Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand
| | - Chanan Angsuthanasombat
- Bacterial Protein Toxin Research Cluster, Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand; Laboratory of Molecular Biophysics and Structural Biochemistry, Biophysics Institute for Research and Development (BIRD), Bangkok 10160, Thailand.
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de Assis Fonseca FC, Firmino AAP, de Macedo LLP, Coelho RR, de Sousa Júnior JDA, Silva-Junior OB, Togawa RC, Pappas GJ, de Góis LAB, da Silva MCM, Grossi-de-Sá MF. Sugarcane giant borer transcriptome analysis and identification of genes related to digestion. PLoS One 2015; 10:e0118231. [PMID: 25706301 PMCID: PMC4338194 DOI: 10.1371/journal.pone.0118231] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 01/11/2015] [Indexed: 11/25/2022] Open
Abstract
Sugarcane is a widely cultivated plant that serves primarily as a source of sugar and ethanol. Its annual yield can be significantly reduced by the action of several insect pests including the sugarcane giant borer (Telchin licus licus), a lepidopteran that presents a long life cycle and which efforts to control it using pesticides have been inefficient. Although its economical relevance, only a few DNA sequences are available for this species in the GenBank. Pyrosequencing technology was used to investigate the transcriptome of several developmental stages of the insect. To maximize transcript diversity, a pool of total RNA was extracted from whole body insects and used to construct a normalized cDNA database. Sequencing produced over 650,000 reads, which were de novo assembled to generate a reference library of 23,824 contigs. After quality score and annotation, 43% of the contigs had at least one BLAST hit against the NCBI non-redundant database, and 40% showed similarities with the lepidopteran Bombyx mori. In a further analysis, we conducted a comparison with Manduca sexta midgut sequences to identify transcripts of genes involved in digestion. Of these transcripts, many presented an expansion or depletion in gene number, compared to B. mori genome. From the sugarcane giant borer (SGB) transcriptome, a number of aminopeptidase N (APN) cDNAs were characterized based on homology to those reported as Cry toxin receptors. This is the first report that provides a large-scale EST database for the species. Transcriptome analysis will certainly be useful to identify novel developmental genes, to better understand the insect's biology and to guide the development of new strategies for insect-pest control.
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Affiliation(s)
- Fernando Campos de Assis Fonseca
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
- Universidade de Brasília, Brasília, Distrito Federal, Brazil
| | - Alexandre Augusto Pereira Firmino
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
- Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Leonardo Lima Pepino de Macedo
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
- Universidade Católica de Brasília, Brasília, Distrito Federal, Brazil
| | - Roberta Ramos Coelho
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
- Universidade de Brasília, Brasília, Distrito Federal, Brazil
| | | | - Orzenil Bonfim Silva-Junior
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
- Universidade Católica de Brasília, Brasília, Distrito Federal, Brazil
| | | | | | | | | | - Maria Fátima Grossi-de-Sá
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
- Universidade Católica de Brasília, Brasília, Distrito Federal, Brazil
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Ferreira LM, Romão TP, Nascimento NAD, Costa MDCMFD, Rezende AM, de-Melo-Neto OP, Silva-Filha MHNL. Non conserved residues between Cqm1 and Aam1 mosquito α-glucosidases are critical for the capacity of Cqm1 to bind the Binary toxin from Lysinibacillus sphaericus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 50:34-42. [PMID: 24746772 DOI: 10.1016/j.ibmb.2014.04.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 03/31/2014] [Accepted: 04/04/2014] [Indexed: 06/03/2023]
Abstract
The Binary (Bin) toxin from the entomopathogenic bacterium Lysinibacillus sphaericus acts on larvae of the culicid Culex quinquefasciatus through its binding to Cqm1, a midgut-bound α-glucosidase. Specific binding by the BinB subunit to the Cqm1 receptor is essential for toxicity however the toxin is unable to bind to the Cqm1 ortholog from the refractory species Aedes aegypti (Aam1). Here, to investigate the molecular basis for the interaction between Cqm1 and BinB, recombinant Cqm1 and Aam1 were first expressed as soluble forms in Sf9 cells. The two proteins were found to display the same glycosilation patterns and BinB binding properties as the native α-glucosidases. Chimeric constructs were then generated through the exchange of reciprocal fragments between the corresponding cqm1 and aam1 cDNAs. Subsequent expression and binding experiments defined a Cqm1 segment encompassing residues S129 and A312 as critical for the interaction with BinB. Through site directed mutagenesis experiments, replacing specific sets of residues from Cqm1 with those of Aam1, the 159GG160 doublet was required for this interaction. Molecular modeling mapped these residues to an exposed loop within the Cqm1's structure, compatible with a target site for BinB and providing a possible explanation for its lack of binding to Aam1.
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Affiliation(s)
- Lígia Maria Ferreira
- Department of Entomology, Centro de Pesquisas Aggeu Magalhães/FIOCRUZ, Recife, PE 50740-465, Brazil
| | - Tatiany Patrícia Romão
- Department of Entomology, Centro de Pesquisas Aggeu Magalhães/FIOCRUZ, Recife, PE 50740-465, Brazil
| | | | | | - Antônio Mauro Rezende
- Department of Microbiology, Centro de Pesquisas Aggeu Magalhães/FIOCRUZ, Recife, PE 50670-420, Brazil
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Valaitis AP, Podgwaite JD. Bacillus thuringiensis Cry1A toxin-binding glycoconjugates present on the brush border membrane and in the peritrophic membrane of the Douglas-fir tussock moth are peritrophins. J Invertebr Pathol 2013; 112:1-8. [DOI: 10.1016/j.jip.2012.10.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 09/19/2012] [Accepted: 10/18/2012] [Indexed: 10/27/2022]
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14
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Ma G, Rahman MM, Grant W, Schmidt O, Asgari S. Insect tolerance to the crystal toxins Cry1Ac and Cry2Ab is mediated by the binding of monomeric toxin to lipophorin glycolipids causing oligomerization and sequestration reactions. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 37:184-192. [PMID: 21925538 DOI: 10.1016/j.dci.2011.08.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 08/30/2011] [Accepted: 08/31/2011] [Indexed: 05/31/2023]
Abstract
Endotoxins from the soil bacterium Bacillus thuringiensis are used worldwide to control insect pests and vectors of diseases. Despite extensive use of the toxins as sprays and in transgenic crops, their mode of action is still not completely known. Here we show that two crystal toxins binding to different glycoprotein receptors have similar glycolipid binding properties. The glycolipid binding domain was identified in a recombinant peptide representing the domain II of the crystal toxin Cry1Ac (M-peptide). The recombinant M-peptide was isolated from bacterial lysates as a mixture of monomers and dimers and formed tetramers upon binding to glycolipid microvesicles from gut tissues and lipid particles from hemolymph plasma. Likewise, when mature toxins and M-peptides where mixed with plasma, these peptides bind to lipid particles and can be separated with lipophorin particles on low-density gradients. When mature toxin and M-peptides are added to lipid particles in increasing amounts, the peptide-particle complexes form higher aggregates that are similar to aggregates formed in low-density gradients in the presence of the toxin. This could indicate that glycolipids on lipid particles are possible targets for toxin monomers in the gut lumen, which upon binding to the glycolipids form tetramers and aggregate particles and thereby sequester the toxin inside the gut lumen before it can interact with receptors on the brush border membrane. The implication is that domain II interacting with glycolipids mediate tolerance to the toxin that is separate from interaction of the toxin with glycoprotein receptors causing toxicity.
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Affiliation(s)
- Gang Ma
- Insect Molecular Biology, Waite Campus, University of Adelaide, Glen Osmond, SA 5064, Australia
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15
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Tajne S, Sanam R, Gundla R, Gandhi NS, Mancera RL, Boddupally D, Vudem DR, Khareedu VR. Molecular modeling of Bt Cry1Ac (DI–DII)–ASAL (Allium sativum lectin)–fusion protein and its interaction with aminopeptidase N (APN) receptor of Manduca sexta. J Mol Graph Model 2012; 33:61-76. [DOI: 10.1016/j.jmgm.2011.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 11/03/2011] [Accepted: 11/04/2011] [Indexed: 01/01/2023]
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16
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Morooka N, Nagata S, Shirai K, Kiguchi K, Nagasawa H. A hemolymph major anionic peptide, HemaP, motivates feeding behavior in the sweetpotato hornworm, Agrius convolvuli. FEBS J 2011; 279:168-79. [PMID: 22035292 DOI: 10.1111/j.1742-4658.2011.08408.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We recently identified a novel feeding-modulating peptide, hemolymph major anionic peptide (HemaP), designated Bommo-HemaP (B-HemaP), from hemolymph of the silkworm Bombyx mori. B-HemaP has a unique biological activity in modulating the regular frequency of feeding motivation, which is accompanied by increased foraging behaviors. To confirm the conservation of the HemaP-regulated feeding mechanism in lepidopteran species, we purified and sequenced two candidate peptides from the hemolymph of larvae of the sweet potato hornworm Agrius convolvuli. Unlike B. mori, A. convolvuli had two forms of HemaP, which were designated Agrco-HemaP-1 (A-HemaP-1) and Agrco-HemaP-2 (A-HemaP-2). The amino acid sequence of A-HemaP-2 was identical with that of A-HemaP-1, except for O-glycosylation on the fifth amino acid, threonine, within the N-terminal region. The amino acid sequence of A-HemaP-1/A-HemaP-2 had only 32% identity with B-HemaP. Structural analysis revealed that the carbohydrate moiety of A-HemaP-2 was an α-GalNAc residue. Injection of A-HemaP-1, A-HemaP-2 and recombinant A-HemaP-1 (rA-HemaP-1) individually caused a significant increase in foraging behaviors in A. convolvuli larvae, and no significant differences were observed among these three A-HemaPs. The CD spectra of these three A-HemaPs were quite similar, and all had α-helix-rich secondary structures. Although A-HemaP-1 and B-HemaP did not exhibit cross-reactivity at any injection doses examined, HemaP might be a conserved molecule among lepidopteran species that can modulate feeding motivation through the fluctuation of peptide levels in hemolymph.
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Affiliation(s)
- Nobukatsu Morooka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
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17
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Budatha M, Ningshen TJ, Dutta-Gupta A. Is hexamerin receptor a GPI-anchored protein in Achaea janata (Lepidoptera: Noctuidae)? J Biosci 2011; 36:545-53. [DOI: 10.1007/s12038-011-9082-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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18
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Likitvivatanavong S, Chen J, Evans AE, Bravo A, Soberon M, Gill SS. Multiple receptors as targets of Cry toxins in mosquitoes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:2829-38. [PMID: 21210704 PMCID: PMC3686494 DOI: 10.1021/jf1036189] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Bacillus thuringiensis (Bt) produces inclusions that are composed of proteins known as crystal proteins or Cry toxins. Due to their high specificity and their safety to humans and the environment, these Cry toxins are considered to be valuable alternatives to chemical pesticides in insect control programs. It is believed that Cry toxin-induced membrane pore formation is responsible for insect toxicity. The molecular mechanism of pore formation involves recognition and subsequent binding of the toxin to membrane receptors. This binding is accompanied by toxin oligomerization and transfer of domain I helices of the toxin to the lipid-water interface. This toxin insertion creates pores that lyse the cells. Several receptors from lepidopteran, coleopteran, and dipteran insects have been well characterized. This paper provides an overview of the understanding of the interactions between Cry toxin and multiple receptors in mosquitoes, in particular Aedes aegypti and reviews the manner by which the receptors were identified and characterized, with a focus on three proteins, cadherin, alkaline phosphatase, and aminopeptidase-N.
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Affiliation(s)
| | - Jianwu Chen
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, 92521, USA
| | - Amy E. Evans
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, 92521, USA
| | - Alejandra Bravo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México. Apdo. postal 510-3, Cuernavaca 62250, Morelos, Mexico
| | - Mario Soberon
- Instituto de Biotecnología, Universidad Nacional Autónoma de México. Apdo. postal 510-3, Cuernavaca 62250, Morelos, Mexico
| | - Sarjeet S. Gill
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, 92521, USA
- Corresponding author: . Tel: 951-827-4621/3547
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Dechklar M, Tiewsiri K, Angsuthanasombat C, Pootanakit K. Functional expression in insect cells of glycosylphosphatidylinositol-linked alkaline phosphatase from Aedes aegypti larval midgut: a Bacillus thuringiensis Cry4Ba toxin receptor. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2011; 41:159-166. [PMID: 21146607 DOI: 10.1016/j.ibmb.2010.11.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 11/18/2010] [Accepted: 11/29/2010] [Indexed: 05/30/2023]
Abstract
Bacillus thuringiensis produces insecticidal crystal (Cry) proteins which bind to cell surface receptors on the brush border membrane of susceptible midgut larvae. The toxin-receptor interaction generates pores in midgut epithelial cells resulting in cell lysis. Here, a cDNA encoding membrane-bound alkaline phosphatase from Aedes aegypti (Aa-mALP) midgut larvae, based on the sequence identity hit to Bombyx mori membrane-bound ALP, was amplified by RT-PCR and transiently expressed in Spodoptera frugiperda (Sf9) insect cells as a 58-kDa membrane-bound protein via the baculovirus expression system and confirmed by digestion with phosphatidylinositol-specific phospholipase C and LC-MS/MS analysis. Immunolocalization results showed that Cry4Ba is able to bind to only Sf9 cells-expressing Aa-mALP. Moreover, these cells were shown to undergo cell lysis in the presence of 100 μg/ml trypsin-treated toxin. Finally, trypan blue exclusion assay also demonstrated an increase in cell death in recombinant cells treated with Cry4Ba. Overall results indicated that Aa-mALP protein was responsible for mediating Cry4Ba toxicity against Sf9 cells, suggesting its role as a receptor for Cry4Ba toxin in A. aegypti mosquito larvae.
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Affiliation(s)
- Manasave Dechklar
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand
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20
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Bacillus thuringiensis Cry toxins bound specifically to various proteins via domain III, which had a galactose-binding domain-like fold. Biosci Biotechnol Biochem 2011; 75:305-12. [PMID: 21307569 DOI: 10.1271/bbb.100689] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cry toxins have been reported to bind not only to receptors on insect cells but also to several unrelated proteins. In this study, we investigated the binding properties of Bacillus thuringiensis Cry toxins, focusing on domain III, a Cry toxin region with a structure that of the galactose-binding domain-like. Cry1Aa, Cry1Ac, and Cry8Ca specifically bound to several proteins unrelated to insect midgut cells. Cry1Aa binding to Cry toxin-binding proteins was inhibited by a monoclonal antibody, 2C2, indicating that Cry1Aa binds to these Cry toxin-binding proteins through domain III. Cry1Aa binding to Bombyx mori aminopeptidase N and other Cry toxin-binding proteins was inhibited by carbonic anhydrase, a Cry toxin-binding protein. The binding regions of carbonic anhydrase and Bombyx mori aminopeptidase N were narrowed to regions of less than 20 amino acids that did not have any similarity, suggesting that Cry toxin domain III has a binding pocket for multiple proteins.
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Developmental penalties associated with inducible tolerance in Helicoverpa armigera to insecticidal toxins from Bacillus thuringiensis. Appl Environ Microbiol 2010; 77:1443-8. [PMID: 21169448 DOI: 10.1128/aem.01467-10] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Exposure of insect larvae to sublethal concentrations of crystal toxins from the soil bacterium Bacillus thuringiensis (Bt toxins) causes the induction of immune and metabolic responses that can be transmitted to offspring by epigenetic inheritance mechanisms. Given that the elevated immune status carries significant developmental penalties, we wanted to establish the relationships between immune induction, tolerance to the toxin and developmental penalties. A laboratory culture of Helicoverpa armigera was induced by a sublethal bacterial suspension containing crystal toxin Cry1Ac in one generation and maintained in the presence of toxin, acquiring significant levels of tolerance to the toxin within 12 generations of continuous exposure. Comparing tolerant and susceptible insects, we show that the induction of larval immune response and the coincident alteration of development-related metabolic activities by elicitors in the larval gut (larval induction) differs from the elevated immune status transmitted by epigenetic mechanisms (embryonic induction). Because the damaging effects of larval induction processes are higher compared to embryonic induction, it is likely that overall developmental penalties depend on the relative contribution of the two induction processes. When insects are kept with the same amount of toxin in the diet for subsequent generations, the embryonic induction process increases its contribution compared to the larval induction, resulting in reduced overall developmental penalty, while tolerance to the toxin is maintained.
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22
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Teese MG, Campbell PM, Scott C, Gordon KHJ, Southon A, Hovan D, Robin C, Russell RJ, Oakeshott JG. Gene identification and proteomic analysis of the esterases of the cotton bollworm, Helicoverpa armigera. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2010; 40:1-16. [PMID: 20005949 DOI: 10.1016/j.ibmb.2009.12.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 12/03/2009] [Accepted: 12/03/2009] [Indexed: 05/28/2023]
Abstract
Some of the resistance of Helicoverpa armigera to conventional insecticides such as organophosphates and synthetic pyrethroids appears to be due to metabolic detoxification by carboxylesterases. To investigate the H. armigera carboxyl/cholinesterases, we created a data set of 39 putative paralogous H. armigera carboxyl/cholinesterase sequences from cDNA libraries and other sources. Phylogenetic analysis revealed a close relationship between these sequences and 70 carboxyl/cholinesterases from the recently sequenced genome of the silkworm, Bombyx mori, including several conserved clades of non-catalytic proteins. A juvenile hormone esterase candidate from H. armigera was identified, and B. mori orthologues were proposed for 31% of the sequences examined, however low similarity was found between lepidopteran sequences and esterases previously associated with insecticide resistance from other insect orders. A proteomic analysis of larval esterases then enabled us to match seven of the H. armigera carboxyl/cholinesterase sequences to specific esterase isozymes. All identified sequences were predicted to encode catalytically active carboxylesterases, including six proteins with N-terminal signal peptides and N-glycans, with two also containing C-terminal signals for glycosylphosphatidylinositol anchor attachment. Five of these sequences were matched to zones of activity on native PAGE at relative mobility values previously associated with insecticide resistance in this species.
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Affiliation(s)
- Mark G Teese
- CSIRO Entomology, GPO Box 1700, Canberra ACT 2601, Australia
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23
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Angelucci C, Barrett-Wilt GA, Hunt DF, Akhurst RJ, East PD, Gordon KH, Campbell PM. Diversity of aminopeptidases, derived from four lepidopteran gene duplications, and polycalins expressed in the midgut of Helicoverpa armigera: identification of proteins binding the delta-endotoxin, Cry1Ac of Bacillus thuringiensis. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2008; 38:685-96. [PMID: 18549954 PMCID: PMC2852237 DOI: 10.1016/j.ibmb.2008.03.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2007] [Revised: 03/28/2008] [Accepted: 03/31/2008] [Indexed: 05/09/2023]
Abstract
Helicoverpa armigera midgut proteins that bind the Bacillus thuringiensis (Bt) delta-endotoxin Cry1Ac were purified by affinity chromatography. SDS-PAGE showed that several proteins were eluted with N-acetylgalactosamine and no further proteins were detected after elution with urea. Tandem mass spectral data for tryptic peptides initially indicated that the proteins resembled aminopeptidases (APNs) from other lepidopterans and cDNA sequences for seven APNs were isolated from H. armigera through a combination of cloning with primers derived from predicted peptide sequences and established EST libraries. Phylogenetic analysis showed lepidopteran APN genes in nine clades of which five were part of a lepidopteran-specific radiation. The Cry1Ac-binding proteins were then identified with four of the seven HaAPN genes. Three of those four APNs are likely orthologs of APNs characterised as Cry1Ac-binding proteins in other lepidopterans. The fourth Cry1Ac-binding APN has orthologs not previously identified as Cry1Ac-binding partners. The HaAPN genes were expressed predominantly in the midgut through larval development. Each showed consistent expression along the length of the midgut but five of the genes were expressed at levels about two orders of magnitude greater than the remaining two. The remaining mass spectral data identified sequences encoding polycalin proteins with multiple lipocalin-like domains. A polycalin has only been previously reported in another lepidopteran, Bombyx mori, but polycalins in both species are now linked with binding of Bt Cry toxins. This is the first report of hybrid, lipocalin-like domains in shorter polycalin sequences that are not present in the longest sequence. We propose that these hybrid domains are generated by alternative splicing of the mRNA.
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Affiliation(s)
| | | | - Donald F. Hunt
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
- Department of Pathology, University of Virginia, Charlottesville, VA 22904, USA
| | | | - Peter D. East
- CSIRO Entomology, PO Box 1700, Canberra, ACT 2601, Australia
| | | | - Peter M. Campbell
- CSIRO Entomology, PO Box 1700, Canberra, ACT 2601, Australia
- Corresponding author. Tel.: +612 62464394; fax: +612 62464173. (P.M. Campbell)
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Expression of Aminopeptidase N1 (APN1), the Main Receptor Protein for Bacillus thuringiensis Cry1A Toxin from Helicoverpa armigera Larval Midgut in Trichoplusia ni cells. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s1671-2927(08)60073-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Bacillus thuringiensis Cry1Ac toxin-binding and pore-forming activity in brush border membrane vesicles prepared from anterior and posterior midgut regions of lepidopteran larvae. Appl Environ Microbiol 2008; 74:1710-6. [PMID: 18223107 DOI: 10.1128/aem.02827-07] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
It is generally accepted that Bacillus thuringiensis Cry toxins insert into the apical membrane of the larval midgut after binding to specific receptors, and there is evidence that the distribution of binding molecules along the midgut is not uniform. By use of the voltage-sensitive dye DiSC(3)(5) and (125)I-labeled Cry1Ac, we have measured the effect of Cry1Ac in terms of permeabilization capacity and of binding parameters on brush border membrane vesicles (BBMV) prepared from the anterior and the posterior regions of the larval midgut from two insect species, Manduca sexta and Helicoverpa armigera. The permeabilizing activity was significantly higher with BBMV from the posterior region than with the one observed in the anterior region in both insect species. Instead, (125)I-Cry1Ac bound specifically to BBMV from the two midgut regions, with no significant differences in the binding parameters between the anterior and posterior regions within an insect species. N-acetylgalactosamine inhibition patterns on pore formation and binding differed between anterior and posterior midgut regions and between species, providing evidence of a multifaceted involvement of the sugar in the Cry1Ac mode of action. The analysis of binding and pore formation in different midgut regions could be an effective method to study differences in the mode of action of Cry1Ac toxin in different species.
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Pigott CR, Ellar DJ. Role of receptors in Bacillus thuringiensis crystal toxin activity. Microbiol Mol Biol Rev 2007; 71:255-81. [PMID: 17554045 PMCID: PMC1899880 DOI: 10.1128/mmbr.00034-06] [Citation(s) in RCA: 402] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Bacillus thuringiensis produces crystalline protein inclusions with insecticidal or nematocidal properties. These crystal (Cry) proteins determine a particular strain's toxicity profile. Transgenic crops expressing one or more recombinant Cry toxins have become agriculturally important. Individual Cry toxins are usually toxic to only a few species within an order, and receptors on midgut epithelial cells have been shown to be critical determinants of Cry specificity. The best characterized of these receptors have been identified for lepidopterans, and two major receptor classes have emerged: the aminopeptidase N (APN) receptors and the cadherin-like receptors. Currently, 38 different APNs have been reported for 12 different lepidopterans. Each APN belongs to one of five groups that have unique structural features and Cry-binding properties. While 17 different APNs have been reported to bind to Cry toxins, only 2 have been shown to mediate toxin susceptibly in vivo. In contrast, several cadherin-like proteins bind to Cry toxins and confer toxin susceptibility in vitro, and disruption of the cadherin gene has been associated with toxin resistance. Nonetheless, only a small subset of the lepidopteran-specific Cry toxins has been shown to interact with cadherin-like proteins. This review analyzes the interactions between Cry toxins and their receptors, focusing on the identification and validation of receptors, the molecular basis for receptor recognition, the role of the receptor in resistant insects, and proposed models to explain the sequence of events at the cell surface by which receptor binding leads to cell death.
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Affiliation(s)
- Craig R Pigott
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
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Borovsky D, Rabindran S, Dawson WO, Powell CA, Iannotti DA, Morris TJ, Shabanowitz J, Hunt DF, DeBondt HL, DeLoof A. Expression of Aedes trypsin-modulating oostatic factor on the virion of TMV: A potential larvicide. Proc Natl Acad Sci U S A 2006; 103:18963-8. [PMID: 17148608 PMCID: PMC1748160 DOI: 10.1073/pnas.0606146103] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Indexed: 11/18/2022] Open
Abstract
We report the engineering of the surface of the tobacco mosaic virus (TMV) virion with a mosquito decapeptide hormone, trypsin-modulating oostatic factor (TMOF). The TMV coat protein (CP) was fused to TMOF at the C terminus by using a read-through, leaky stop codon that facilitated expression of CP and chimeric CP-TMOF (20:1 ratio) that were coassembled into virus particles in infected Nicotiana tabacum. Plants that were infected with the hybrid TMV RNA accumulated TMOF to levels of 1.3% of total soluble protein. Infected tobacco leaf discs that were fed to Heliothis virescens fourth-instar larvae stunted their growth and inhibited trypsin and chymotrypsin activity in their midgut. Purified CP-TMOF virions fed to mosquito larvae stopped larval growth and caused death. Because TMV has a wide host range, expressing TMV-TMOF in plants can be used as a general method to protect them against agricultural insect pests and to control vector mosquitoes.
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Affiliation(s)
- Dov Borovsky
- Florida Medical Entomology Laboratory, University of Florida-Institute of Food and Agricultural Sciences (IFAS), 200 Ninth Street Southeast, Vero Beach, FL 32962-4699, USA.
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28
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Romão TP, de Melo Chalegre KD, Key S, Ayres CFJ, Fontes de Oliveira CM, de-Melo-Neto OP, Silva-Filha MHNL. A second independent resistance mechanism to Bacillus sphaericus binary toxin targets its alpha-glucosidase receptor in Culex quinquefasciatus. FEBS J 2006; 273:1556-68. [PMID: 16689941 DOI: 10.1111/j.1742-4658.2006.05177.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The entomopathogen Bacillus sphaericus is an important tool for the vector control of Culex sp., and its effectiveness has been validated in field trials. The appearance of resistance to this bacterium, however, remains a threat to its use, and attempts have been made to understand the resistance mechanisms. Previous work showed that the resistance to B. sphaericus in a Culex quinquefasciatus colony is associated with the absence of the approximately 60-kDa binary toxin receptor in larvae midgut microvilli. Here, the gene encoding the C. quinquefasciatus toxin receptor, Cqm1, was cloned and sequenced from a susceptible colony. The deduced amino-acid sequence confirmed its identity as an alpha-glucosidase, and analysis of the corresponding gene sequence from resistant larvae implicated a 19-nucleotide deletion as the basis for resistance. This deletion changes the ORF and originates a premature stop codon, which prevents the synthesis of the full-length Cqm1. Expression of the truncated protein, however, was not detected when whole larvae extracts were probed with antibodies raised against an N-terminal 45-kDa recombinant fragment of Cqm1. It seems that the premature stop codon directs the mutated cqm1 to the nonsense-mediated decay pathway of mRNA degradation. In-gel assays confirmed that a single alpha-glucosidase protein is missing from the resistant colony. Further in vitro affinity assays showed that the recombinant fragment binds to the toxin, and mapped the binding site to the N-terminus of the receptor.
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Affiliation(s)
- Tatiany Patrícia Romão
- Department of Entomology, Centro de Pesquisas Aggeu Magalhães/Fundação Oswaldo Cruz, Recife-PE, Brazil
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29
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Crickmore N. Using worms to better understand how Bacillus thuringiensis kills insects. Trends Microbiol 2005; 13:347-50. [PMID: 15967665 DOI: 10.1016/j.tim.2005.06.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2005] [Revised: 05/23/2005] [Accepted: 06/08/2005] [Indexed: 11/24/2022]
Abstract
Bacillus thuringiensis is widely used as a biological pesticide to control insects that either cause damage to crops or transmit disease. That it can also target the model organism Caenorhabditis elegans has not only provided exciting new insights into how the toxins produced by the bacterium target their victims but also how target insects counter the attack. Modern approaches such as reverse genetics and microarray technology have revealed novel receptors for the toxins and possible signal transduction pathways induced within the host following intoxication. This article will discuss how these findings fit in with current models and how they might influence future studies.
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Affiliation(s)
- Neil Crickmore
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK.
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30
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Chen J, Brown MR, Hua G, Adang MJ. Comparison of the localization of Bacillus thuringiensis Cry1A δ-endotoxins and their binding proteins in larval midgut of tobacco hornworm, Manduca sexta. Cell Tissue Res 2005; 321:123-9. [PMID: 15902495 DOI: 10.1007/s00441-005-1124-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2005] [Accepted: 03/18/2005] [Indexed: 11/30/2022]
Abstract
Tobacco hornworm, Manduca sexta, is a model insect for studying the action of Bacillus thuringiensis (Bt) Cry toxins on lepidopterans. The proteins, which bind Bt toxins to midgut epithelial cells, are key factors involved in the insecticidal functions of the toxins. Three Cry1A-binding proteins, viz., aminopeptidase N (APN), the cadherin-like Bt-R1, and membrane-type alkaline phosphatase (m-ALP), were localized, by immunohistochemistry, in sections from the anterior, middle, and posterior regions of the midgut from second instar M. sexta larvae. Both APN and m-ALP were distributed predominantly along microvilli in the posterior region and to a lesser extent on the apical tip of microvilli in the anterior and middle regions. Bt-R1 was localized at the base of microvilli in the anterior region, over the entire microvilli in the middle region, and at both the apex and base of microvilli in the posterior region. The localization of rhodamine-labeled Cry1Aa, Cry1Ab, and Cry1Ac binding was determined on sections from the same midgut regions. Cry1Aa and Cry1Ab bound to the apical tip of microvilli almost equally in all midgut regions. Binding of Cry1Ac was much stronger in the posterior region than in the anterior and middle regions. Thus, binding sites for Bt proteins and Cry1A toxins are co-localized on the microvilli of M. sexta midgut epithelial cells.
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Affiliation(s)
- Jiang Chen
- Department of Entomology, University of Georgia, Athens, GA 30602-2603, USA
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31
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Mina‐Osorio P, Ortega E. Aminopeptidase N (CD13) functionally interacts with FcgammaRs in human monocytes. J Leukoc Biol 2005; 77:1008-17. [PMID: 15758076 PMCID: PMC7167080 DOI: 10.1189/jlb.1204714] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Aminopeptidase N (E.C. 3.4.11.2) is a membrane-bound metalloproteinase expressed in many tissues. Although its cytoplasmic portion has only eight amino acids, cross-linking of CD13 by monoclonal antibodies (mAb) has been shown to trigger intracellular signaling. A functional association between CD13 and receptors for immunoglobulin G (FcgammaRs) has been proposed. In this work, we evaluated possible functional interactions between CD13 and FcgammaRs in human peripheral blood monocytes and in U-937 promonocytic cells. Our results show that during FcgammaR-mediated phagocytosis, CD13 redistributes to the phagocytic cup and is internalized into the phagosomes. Moreover, modified erythrocytes that interact with the monocytic cell membrane through FcgammaRI and CD13 are ingested simultaneously, more efficiently than those that interact through the FcgammaRI only. Also, co-cross-linking of CD13 with FcgammaRI by specific mAbs increases the level and duration of Syk phosphorylation induced by FcgammaRI cross-linking. Finally, FcgammaRI and CD13 colocalize in zones of cellular polarization and coredistribute after aggregation of either of them. These results demonstrate that CD13 and FcgammaRI can functionally interact on the monocytic cell membrane and suggest that CD13 may act as a signal regulator of FcgammaR function.
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Affiliation(s)
- Paola Mina‐Osorio
- Department of Immunology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México
| | - Enrique Ortega
- Department of Immunology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México
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32
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Mucha J, Domlatil J, Lochnit G, Rendić D, Paschinger K, HINTERKöRNER G, Hofinger A, Kosma P, Wilson I. The Drosophila melanogaster homologue of the human histo-blood group Pk gene encodes a glycolipid-modifying alpha1,4-N-acetylgalactosaminyltransferase. Biochem J 2005; 382:67-74. [PMID: 15130086 PMCID: PMC1133916 DOI: 10.1042/bj20040535] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Revised: 04/29/2004] [Accepted: 05/07/2004] [Indexed: 11/17/2022]
Abstract
Insects express arthro-series glycosphingolipids, which contain an alpha1,4-linked GalNAc residue. To determine the genetic basis for this linkage, we cloned a cDNA (CG17223) from Drosophila melanogaster encoding a protein with homology to mammalian alpha1,4-glycosyltransferases and expressed it in the yeast Pichia pastoris. Culture supernatants from the transformed yeast were found to display a novel UDP-GalNAc:GalNAcbeta1,4GlcNAcbeta1-R alpha-N-acetylgalactosaminyltransferase activity when using either a glycolipid, p-nitrophenylglycoside or an N-glycan carrying one or two terminal beta-N-acetylgalactosamine residues. NMR and MS in combination with glycosidase digestion and methylation analysis indicate that the cloned cDNA encodes an alpha1,4-N-acetylgalactosaminyltransferase. We hypothesize that this enzyme and its orthologues in other insects are required for the biosynthesis of the N5a and subsequent members of the arthro-series of glycolipids as well as of N-glycan receptors for Bacillus thuringiensis crystal toxin Cry1Ac.
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Affiliation(s)
- Ján Mucha
- *Chemický ústav, Slovenská akadémia vied, Dúbravská cesta 9, 845 38 Bratislava, Slovakia
| | - Jiří Domlatil
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Günter Lochnit
- ‡Institut für Biochemie, Justus-Liebig-Universität Giessen, Friedrichstrasse 24, D-35392 Giessen, Germany
| | - Dubravko Rendić
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Katharina Paschinger
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Georg HINTERKöRNER
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Andreas Hofinger
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Paul Kosma
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Iain B. H. Wilson
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
- To whom correspondence should be addressed (email )
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The N-linked oligosaccharides of aminopeptidase N from Manduca sexta: site localization and identification of novel N-glycan structures. ACTA ACUST UNITED AC 2004; 271:4241-58. [PMID: 15511230 DOI: 10.1111/j.1432-1033.2004.04364.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mass spectrometric studies on the N-linked glycans of aminopeptidase 1 from Manduca sexta have revealed unusual structures not previously observed on any insect glycoprotein. Structure elucidation of these oligosaccharides was carried out by high-energy collision-induced dissociation (CID) using a matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) tandem mass spectrometer. These key experiments revealed that three out of the four N-linked glycosylation sites in this protein (Asn295, Asn623 and Asn752) are occupied with highly fucosylated N-glycans that possess unusual difucosylated cores. Cross-ring fragment ions and 'internal' fragment ions observed in the CID spectra, showed that these fucoses are found at the 3-position of proximal GlcNAc and at the 3-position of distal GlcNAc in the chitobiose unit. The latter substitution has only been previously observed in nematodes. In addition, these core structures can be decorated with novel fucosylated antennae composed of Fucalpha(1-3)GlcNAc. Key fragment ions revealed that these antennae are predominantly found on the upper 6-arm of the core mannose. The paucimannosidic N-glycan (Man(3)GlcNAc(2)), commonly found on other insect glycoproteins, is the predominant oligosaccharide found at the remaining N-glycosylation site (Asn609).
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