1
|
Jin L, Zhang BW, Lu JW, Liao JA, Zhu QJ, Lin Y, Yu XQ. The mechanism of Cry41-related toxin against Myzus persicae based on its interaction with Buchnera-derived ATP-dependent 6-phosphofructokinase. PEST MANAGEMENT SCIENCE 2023; 79:1684-1691. [PMID: 36602054 DOI: 10.1002/ps.7340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/29/2022] [Accepted: 12/26/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Myzus persicae (Hemiptera: Aphididae) is one of the most notorious pests of many crops worldwide. Most Cry toxins produced by Bacillus thuringiensis show very low toxicity to M. persicae; however, a study showed that Cry41-related toxin had moderate toxic activity against M. persicae. In our previous work, potential Cry41-related toxin-binding proteins in M. persicae were identified, including cathepsin B, calcium-transporting ATPase, and Buchnera-derived ATP-dependent 6-phosphofructokinase (PFKA). Buchnera is an endosymbiont present in almost all aphids and it provides necessary nutrients for aphid growth. This study investigated the role of Buchnera-derived PFKA in Cry41-related toxicity against M. persicae. RESULTS In this study, recombinant PFKA was expressed and purified, and in vitro assays revealed that PFKA bound to Cry41-related toxin, and Cry41-related toxin at 25 μg ml-1 significantly inhibited the activity of PFKA. In addition, when M. persicae was treated with 30 μg ml-1 of Cry41-related toxin for 24 h, the expression of dnak, a single-copy gene in Buchnera, was significantly decreased, indicating a decrease in the number of Buchnera. CONCLUSION Our results suggest that Cry41-related toxin interacts with Buchnera-derived PFKA to inhibit its enzymatic activity and likely impair cell viability, resulting in a decrease in the number of Buchnera, and finally leading to M. persicae death. These findings open up new perspectives in our understanding of the mode of action of Cry toxins and are useful in helping improve Cry toxicity for aphid control. © 2023 Society of Chemical Industry.
Collapse
Affiliation(s)
- Liang Jin
- Fujian Provincial Key Laboratory of Biochemical Technology (Huaqiao University), Department of Bioengineering & Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Bin-Wu Zhang
- Fujian Provincial Key Laboratory of Biochemical Technology (Huaqiao University), Department of Bioengineering & Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Jing-Wen Lu
- Fujian Provincial Key Laboratory of Biochemical Technology (Huaqiao University), Department of Bioengineering & Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Jun-Ao Liao
- Fujian Provincial Key Laboratory of Biochemical Technology (Huaqiao University), Department of Bioengineering & Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Qi-Jun Zhu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yi Lin
- Fujian Provincial Key Laboratory of Biochemical Technology (Huaqiao University), Department of Bioengineering & Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Xiao-Qiang Yu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| |
Collapse
|
2
|
Xiao Z, Yao X, Bai S, Wei J, An S. Involvement of an Enhanced Immunity Mechanism in the Resistance to Bacillus thuringiensis in Lepidopteran Pests. INSECTS 2023; 14:151. [PMID: 36835720 PMCID: PMC9965922 DOI: 10.3390/insects14020151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 01/21/2023] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
Bacillus thuringiensis (Bt) is the safest, economically successful entomopathogen to date. It is extensively produced in transgenic crops or used in spray formulations to control Lepidopteran pests. The most serious threat to the sustainable usage of Bt is insect resistance. The resistance mechanisms to Bt toxins depend not only on alterations in insect receptors, but also on the enhancement of insect immune responses. In this work, we review the current knowledge of the immune response and resistance of insects to Bt formulations and Bt proteins, mainly in Lepidopteran pests. We discuss the pattern recognition proteins for recognizing Bt, antimicrobial peptides (AMPs) and their synthetic signaling pathways, the prophenoloxidase system, reactive oxygen species (ROS) generation, nodulation, encapsulation, phagocytosis, and cell-free aggregates, which are involved in immune response reactions or resistance to Bt. This review also analyzes immune priming, which contributes to the evolution of insect resistance to Bt, and puts forward strategies to improve the insecticidal activity of Bt formulations and manage insect resistance, targeting the insect immune responses and resistance.
Collapse
|
3
|
Zhang Y, Zhang P, Yu R, Li B. A C-type lectin TcCTL1 is required for embryogenesis in Tribolium castaneum. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 139:104560. [PMID: 36191687 DOI: 10.1016/j.dci.2022.104560] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/24/2022] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
C-type lectin S group (CTL-S) plays a variety of roles in invertebrate including pathogen recognition and activation of immune responses. Previous studies have shown that CTL-S subfamily of Tribolium castaneum is mainly divided into two clades, of which only TcCTL1 was separately located in one clade. However, it remains unclear whether TcCTL1 occurs the differentiation of function. Therefore, the CTL-S TcCTL1 gene was cloned and characterized from T. castaneum. Functional analysis revealed that TcCTL1 could recognize and agglutinate pathogens, as well as activate immune signaling pathways to participate in immune response, which was consistent with our previously reported for TcCTL5 and TcCTL6. Differently, RNAi of TcCTL1 discovered that the egg produced by dsTcCTL1-treated adult could not hatch into larvae. Further DAPI-straining embryo indicated that the process of embryogenesis in dsTcCTL1-treated beetle was defeated, implying that TcCTL1 is required for embryogenesis in T. castaneum except for immune response. These results will aid implications for the understanding of CTL-S in invertebrate.
Collapse
Affiliation(s)
- Yonglei Zhang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Ping Zhang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Runnan Yu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Bin Li
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China.
| |
Collapse
|
4
|
Alam I, Batool K, Idris AL, Tan W, Guan X, Zhang L. Function of CTLGA9 Amino Acid Residue Leucine-6 in Modulating Cry Toxicity. Front Immunol 2022; 13:906259. [PMID: 35865517 PMCID: PMC9294448 DOI: 10.3389/fimmu.2022.906259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 06/06/2022] [Indexed: 12/02/2022] Open
Abstract
Aedes aegypti is a crucial vector for many arboviral diseases that cause millions of deaths worldwide and thus is of major public health concern. Crystal (Cry) proteins, which are toxins produced by Bacillus thuringiensis, are structurally organized into three-domains, of which domain II is the most variable in terms of binding towards various toxin receptors. The binding of Cry11Aa to putative receptor such as aminopeptidase-N (APN) is explicitly inhibited by midgut C-type lectins (CTLs). The similarity between the domain II fold of Cry11Aa toxin and the carbohydrate recognition domain in the CTLs is a possible structural basis for the involvement of Cry domain II in the recognition of carbohydrates on toxin receptors. In this study, a site-directed point mutation was introduced into the A. aegypti CTLGA9 gene on the basis of molecular docking findings, leading to substitution of the Leucine-6 (Leu-6) residue in the protein with alanine. Subsequently, functional monitoring of the mutated protein was carried out. Unlike the amino acid residues of wild-type CTLGA9, none of the residues of mutant (m) CTLGA9 were competed with Cry11Aa for binding to the APN receptor interface. Additionally, ligand blot analysis showed that both wild-type and mutant CTLGA9 had similar abilities to bind to APN and Cry11Aa. Furthermore, in the competitive ELISA in which labeled mutant CTLGA9 (10 nM) was mixed with increasing concentrations of unlabeled Cry11Aa (0–500 nM), the mutant showed no competition with Cry11Aa for binding to APN., By contrast, in the positive control sample of labeled wild type CTLGA9 mixed with same concentrations of Cry11Aa competition between the two ligands for binding to the APN was evident. These results suggest that Leucine-6 may be the key site involved in the competitive receptor binding between CTLGA9 and Cry11Aa. Moreover, according to the bioassay results, mutant CTLGA9 could in fact enhance the toxicity of Cry11Aa. Our novel findings provide further insights into the mechanism of Cry toxicity as well as a theoretical basis for enhancing the mosquitocidal activity of these toxin through molecular modification strategies.
Collapse
Affiliation(s)
- Intikhab Alam
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Khadija Batool
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Aisha Lawan Idris
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Weilong Tan
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lingling Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
- *Correspondence: Lingling Zhang,
| |
Collapse
|
5
|
Yin Y, Cao K, Zhao X, Cao C, Dong X, Liang J, Shi W. Bt Cry1Ab/2Ab toxins disrupt the structure of the gut bacterial community of Locusta migratoria through host immune responses. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 238:113602. [PMID: 35526455 DOI: 10.1016/j.ecoenv.2022.113602] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 04/26/2022] [Accepted: 05/01/2022] [Indexed: 06/14/2023]
Abstract
The gut microbiota of insects plays a vital role in digestion, nutrient acquisition, metabolism of dietary toxins, pathogen immunity and maintenance of gut homeostasis. Bacillus thuringinensis (Bt) poisons target insects through its toxins that are activated in the insect gut. The effects of Bt toxins on gut microbiota of insects and their underlying mechanisms are not well understood. In this study, we found that Cry1Ab/2Ab toxins significantly changed the gut bacterial community's structure and reduced the total load of gut bacteria in the Locusta migratoria. In addition, Cry toxins significantly increased the level of reactive oxygen species (ROS) in the gut of locusts. Our results also showed that Cry1Ab/2Ab toxins induced the host gut's immune response by up-regulating of key genes in the Immune deficiency (IMD) and Toll pathway. RNA interference showed that knocking down Relish could narrow the difference in the load, diversity, and composition in gut bacteria caused by Cry toxins. Our findings suggest that Bt potentially influences the gut bacterial community of L. migratoria through host immune response.
Collapse
Affiliation(s)
- Yue Yin
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing 100094, China.
| | - Kaili Cao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing 100094, China.
| | - Xinxin Zhao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing 100094, China.
| | - Chuan Cao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing 100094, China.
| | - Xuehui Dong
- Department of Agriculture Science, China Agricultural University, Beijing 100094, China.
| | - Jingang Liang
- Development Center of Science and Technology, Ministry of Agriculture and Rural Affairs, Beijing 100176, China.
| | - Wangpeng Shi
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing 100094, China.
| |
Collapse
|
6
|
Li Q, Li M, Zhu M, Zhong J, Wen L, Zhang J, Zhang R, Gao Q, Yu XQ, Lu Y. Genome-wide identification and comparative analysis of Cry toxin receptor families in 7 insect species with a focus on Spodoptera litura. INSECT SCIENCE 2022; 29:783-800. [PMID: 34405540 DOI: 10.1111/1744-7917.12961] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/30/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
Cadherin, aminopeptidase N (APN) and alkaline phosphatase (ALP) have been characterized as Cry receptors. In this study, comparative genomic analysis of the 3 receptor families was performed in 7 insects. ALPs and APNs are divided into three and eight clades in phylogenetic trees, respectively. ALPs in clade 3 and APNs in clade 1 contain multiple paralogs within each species and most paralogs are located closely in chromosomes. Drosophila melanogaster has expanded APNs in clade 5 and were lowly expressed in midgut. Cadherins are divided into 16 clades; they may diverge before holometabolous insect speciation except for BtR and Cad89D-like clades. Eight insects from different orders containing BtR orthologs are sensitive to Cry1A or Cry3A, while five species without BtR are insensitive to both toxins. Most APNs in clade 1, several ALPs in clade 3, BtR and Cad89D-like genes were highly or moderately expressed in larval midgut of Spodoptera litura and the other six species, and several members in these clades have been identified as Cry receptors. Expressions of putative S. litura Cry receptors in the midgut after exposing to Bt toxins were also analyzed.
Collapse
Affiliation(s)
- Qilin Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Mengge Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Mengyao Zhu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Jielai Zhong
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Liang Wen
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Jie Zhang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Ruonan Zhang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Qiang Gao
- College of Biology, Hunan University, Changsha, 410082, China
| | - Xiao-Qiang Yu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Yuzhen Lu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| |
Collapse
|
7
|
Alam I, Batool K, Idris AL, Tan W, Guan X, Zhang L. Role of Lectin in the Response of Aedes aegypti Against Bt Toxin. Front Immunol 2022; 13:898198. [PMID: 35634312 PMCID: PMC9136036 DOI: 10.3389/fimmu.2022.898198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 04/19/2022] [Indexed: 12/05/2022] Open
Abstract
Aedes aegypti is one of the world’s most dangerous mosquitoes, and a vector of diseases such as dengue fever, chikungunya virus, yellow fever, and Zika virus disease. Currently, a major global challenge is the scarcity of antiviral medicine and vaccine for arboviruses. Bacillus thuringiensis var israelensis (Bti) toxins are used as biological mosquito control agents. Endotoxins, including Cry4Aa, Cry4Ba, Cry10Aa, Cry11Aa, and Cyt1Aa, are toxic to mosquitoes. Insect eradication by Cry toxin relies primarily on the interaction of cry toxins with key toxin receptors, such as aminopeptidase (APN), alkaline phosphatase (ALP), cadherin (CAD), and ATP-binding cassette transporters. The carbohydrate recognition domains (CRDs) of lectins and domains II and III of Cry toxins share similar structural folds, suggesting that midgut proteins, such as C-type lectins (CTLs), may interfere with interactions among Cry toxins and receptors by binding to both and alter Cry toxicity. In the present review, we summarize the functional role of C-type lectins in Ae. aegypti mosquitoes and the mechanism underlying the alteration of Cry toxin activity by CTLs. Furthermore, we outline future research directions on elucidating the Bti resistance mechanism. This study provides a basis for understanding Bti resistance, which can be used to develop novel insecticides.
Collapse
Affiliation(s)
- Intikhab Alam
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Khadija Batool
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Aisha Lawan Idris
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Weilong Tan
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lingling Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
- *Correspondence: Lingling Zhang,
| |
Collapse
|
8
|
Chen P, De Schutter K, Van Damme EJM, Smagghe G. Can Plant Lectins Help to Elucidate Insect Lectin-Mediated Immune Response? INSECTS 2021; 12:insects12060497. [PMID: 34071763 PMCID: PMC8226959 DOI: 10.3390/insects12060497] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 05/23/2021] [Accepted: 05/25/2021] [Indexed: 12/25/2022]
Abstract
Simple Summary Lectins are proteins that can recognize and selectively bind specific sugar structures. These proteins are present in all kingdoms of life, including plants, animals, fungi and microorganisms and play a role in a broad range of processes. The interactions between lectins and their target carbohydrates play a primordial role in plant and animal immune systems. Despite being the largest and most diverse taxa on earth, the study of lectins and their functions in insects is lagging behind. To study the role of insect lectins in the immune response, plant lectins could provide an interesting tool. Plant lectins have been well characterized and many of them possess immunomodulatory properties in vertebrate cells. The increasing knowledge on the immunomodulatory effects of plant lectins could complement the missing knowledge on the endogenous insect lectins and contribute to understanding the processes and mechanisms by which lectins participate in insect immunity. This review summarizes existing studies of immune responses stimulated by endogenous or exogenous lectins. Abstract Lectins are carbohydrate-binding proteins that recognize and selectively bind to specific sugar structures. This group of proteins is widespread in plants, animals, and microorganisms, and exerts a broad range of functions. Many plant lectins were identified as exogenous stimuli of vertebrate immunity. Despite being the largest and most diverse taxon on earth, the study of lectins and their functions in insects is lagging behind. In insects, research on lectins and their biological importance has mainly focused on the C-type lectin (CTL) family, limiting our global understanding of the function of insect lectins and their role in insect immunity. In contrast, plant lectins have been well characterized and the immunomodulatory effects of several plant lectins have been documented extensively in vertebrates. This information could complement the missing knowledge on endogenous insect lectins and contribute to understanding of the processes and mechanisms by which lectins participate in insect immunity. This review summarizes existing studies of immune responses stimulated by endogenous or exogenous lectins. Understanding how lectins modulate insect immune responses can provide insight which, in turn, can help to elaborate novel ideas applicable for the protection of beneficial insects and the development of novel pest control strategies.
Collapse
Affiliation(s)
- Pengyu Chen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium; (P.C.); (K.D.S.)
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium;
| | - Kristof De Schutter
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium; (P.C.); (K.D.S.)
| | - Els J. M. Van Damme
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium;
| | - Guy Smagghe
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium; (P.C.); (K.D.S.)
- Correspondence:
| |
Collapse
|
9
|
Knockout of Two Cry-Binding Aminopeptidase N Isoforms Does Not Change Susceptibility of Aedes aegypti Larvae to Bacillus thuringiensis subsp. israelensis Cry4Ba and Cry11Aa Toxins. INSECTS 2021; 12:insects12030223. [PMID: 33807543 PMCID: PMC8002144 DOI: 10.3390/insects12030223] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 02/26/2021] [Accepted: 03/02/2021] [Indexed: 11/17/2022]
Abstract
Simple Summary The midgut aminopeptidase N (APN) isoforms have been identified as the binding receptor of insecticidal Cry toxins in numerous insects, including the major arbovirus vector Aedes aegypti (Ae. aegypti). However, whether the Cry-binding APN acts as an essential functional receptor to mediate Bacillus thuringiensis subsp. israelensis (Bti) toxicity in Ae. aegypti larvae remains to be determined. In this study, our results provide the direct molecular evidence demonstrating that two Cry-binding APN isoforms (AeAPN1 and AeAPN2) did not play a key role in mediating Bti Cry4Ba and Cry11Aa toxicity in Ae. aegypti larvae. Abstract The insecticidal Cry4Ba and Cry11Aa crystal proteins from Bacillus thuringiensis subsp. israelensis (Bti) are highly toxic to Ae. aegypti larvae. The glycosylphosphatidylinositol (GPI)-anchored APN was identified as an important membrane-bound receptor for multiple Cry toxins in numerous Lepidoptera, Coleoptera, and Diptera insects. However, there is no direct molecular evidence to link APN of Ae. aegypti to Bti toxicity in vivo. In this study, two Cry4Ba/Cry11Aa-binding Ae. aegypti GPI-APN isoforms (AeAPN1 and AeAPN2) were individually knocked-out using CRISPR/Cas9 mutagenesis, and the AeAPN1/AeAPN2 double-mutant homozygous strain was generated using the reverse genetics approach. ELISA assays showed that the high binding affinity of Cry4Ba and Cry11Aa protoxins to the midgut brush border membrane vesicles (BBMVs) from these APN knockouts was similar to the background from the wild-type (WT) strain. Likewise, the bioassay results showed that neither the single knockout of AeAPN1 or AeAPN2, nor the simultaneous disruption of AeAPN1 and AeAPN2 resulted in significant changes in susceptibility of Ae. aegypti larvae to Cry4Ba and Cry11Aa toxins. Accordingly, our results suggest that AeAPN1 and AeAPN2 may not mediate Bti Cry4Ba and Cry11Aa toxicity in Ae. aegypti larvae as their binding proteins.
Collapse
|
10
|
Li S, Xu X, De Mandal S, Shakeel M, Hua Y, Shoukat RF, Fu D, Jin F. Gut microbiota mediate Plutella xylostella susceptibility to Bt Cry1Ac protoxin is associated with host immune response. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 271:116271. [PMID: 33401210 DOI: 10.1016/j.envpol.2020.116271] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/27/2020] [Accepted: 12/08/2020] [Indexed: 06/12/2023]
Abstract
Insect gut microbiotas have a variety of physiological functions for host growth, development, and immunity. Bacillus thuringiensis (Bt) is known to kill insect pests by releasing insecticidal protoxins, which are activated in the insect midgut. However, the interplay among Bt infection, host immunity, and gut microbiota are still unclear. Here we show that Bt Cry1Ac protoxin interacts with the gut microbiota to accelerate the mortality of P. xylostella larvae. Cry1Ac protoxin was found to cause a dynamic change in the midgut and hemocoel microbiota of P. xylostella, with a significant increase in bacterial load and a significant reduction in bacterial diversity. In turn, loss of gut microbiota significantly decreased the Bt susceptibility of P. xylostella larvae. The introduction of three gut bacterial isolates Enterococcus mundtii (PxG1), Carnobacterium maltaromaticum (PxCG2), and Acinetobacter guillouiae (PxCG3) restored sensitivity to Bt Cry1Ac protoxin. We also found that Cry1Ac protoxin and native gut microbiota can trigger host midgut immune response, which involves the up-regulation of expression of Toll and IMD pathway genes and most antimicrobial peptide genes, respectively. Our findings further shed light on the interplay between insect gut microbiota and host immunity under the Bt toxin killing pressure, and this may provide insights for improving the management of Bt resistance and lead to new strategies for biological control of insect pests.
Collapse
Affiliation(s)
- Shuzhong Li
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Xiaoxia Xu
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Surajit De Mandal
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Muhammad Shakeel
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Yanyan Hua
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Rana Fartab Shoukat
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Dongran Fu
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China
| | - Fengliang Jin
- College of Plant Protection, South China Agricultural University, Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Guangzhou, PR China.
| |
Collapse
|
11
|
The Tripartite Interaction of Host Immunity- Bacillus thuringiensis Infection-Gut Microbiota. Toxins (Basel) 2020; 12:toxins12080514. [PMID: 32806491 PMCID: PMC7472377 DOI: 10.3390/toxins12080514] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/05/2020] [Accepted: 08/07/2020] [Indexed: 12/12/2022] Open
Abstract
Bacillus thuringiensis (Bt) is an important cosmopolitan bacterial entomopathogen, which produces various protein toxins that have been expressed in transgenic crops. The evolved molecular interaction between the insect immune system and gut microbiota is changed during the Bt infection process. The host immune response, such as the expression of induced antimicrobial peptides (AMPs), the melanization response, and the production of reactive oxygen species (ROS), varies with different doses of Bt infection. Moreover, B. thuringiensis infection changes the abundance and structural composition of the intestinal bacteria community. The activated immune response, together with dysbiosis of the gut microbiota, also has an important effect on Bt pathogenicity and insect resistance to Bt. In this review, we attempt to clarify this tripartite interaction of host immunity, Bt infection, and gut microbiota, especially the important role of key immune regulators and symbiotic bacteria in the Bt killing activity. Increasing the effectiveness of biocontrol agents by interfering with insect resistance and controlling symbiotic bacteria can be important steps for the successful application of microbial biopesticides.
Collapse
|
12
|
Hu X, Chen H, Xu J, Zhao G, Huang X, Liu J, Batool K, Wu C, Wu S, Huang E, Wu J, Chowhury M, Zhang J, Guan X, Yu XQ, Zhang L. Function of Aedes aegypti galectin-6 in modulation of Cry11Aa toxicity. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2020; 162:96-104. [PMID: 31836060 DOI: 10.1016/j.pestbp.2019.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 07/09/2019] [Accepted: 09/18/2019] [Indexed: 06/10/2023]
Abstract
Galectins are a family of β-galactoside binding proteins, and insect galectins play a role in immune responses and may also affect Cry toxin activity. In this study, we aimed to further understand the function and molecular mechanism of Aedes aegypti galectin-6 in modulation of Cry11Aa toxicity. A. aegypti galectin-6 was cloned, and the recombinant galectin-6 was expressed and purified. Bioassays indicated that galectin-6 could reduce the toxicity of Cry11Aa, protecting A. aegypti larvae. To determine interactions among galectin-6, Cry11Aa and putative toxin receptors, Octet Red System, western blotting, far-western blotting and ELISA assays were performed. Octet Red System showed that galectin-6 bound to BBMVs of A. aegypti larvae with lower affinity than that of Cry11Aa. Western blotting and far-western blotting analyses demonstrated that galectin-6 bound to A. aegypti ALP1 and APN2 as well as to BBMVs, consistent with the results of ELISA and protein docking simulations. However, galectin-6 did not bind to Cadherin in far-western blotting or ELISA assay, though the protein docking simulations suggested their binding potential. These findings support the conclusion that galectin-6 may block Cry11Aa from binding to ALP1 and APN2 due to structural similarity, which might decrease the mosquitocidal toxicity of Cry11Aa.
Collapse
Affiliation(s)
- Xiaohua Hu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Hong Chen
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jin Xu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Guohui Zhao
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xianhui Huang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jiannan Liu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Khadija Batool
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Chenxu Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Songqing Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Enjiong Huang
- Fujian International Travel Healthcare Center, Fuzhou 350001, China
| | - Juan Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Munmun Chowhury
- Division of Cell Biology and Biophysics, University of Missouri, Kansas City, MO 64110, USA
| | - Jie Zhang
- Division of Cell Biology and Biophysics, University of Missouri, Kansas City, MO 64110, USA
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xiao-Qiang Yu
- Division of Cell Biology and Biophysics, University of Missouri, Kansas City, MO 64110, USA.
| | - Lingling Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Division of Cell Biology and Biophysics, University of Missouri, Kansas City, MO 64110, USA.
| |
Collapse
|
13
|
Batool K, Alam I, Jin L, Xu J, Wu C, Wang J, Huang E, Guan X, Yu XQ, Zhang L. CTLGA9 Interacts with ALP1 and APN Receptors To Modulate Cry11Aa Toxicity in Aedes aegypti. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:8896-8904. [PMID: 31339308 DOI: 10.1021/acs.jafc.9b01840] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The mosquito Aedes aegypti is associated with the spread of many viral diseases in humans, including Dengue virus (DENVs), Yellow fever virus (YFV), Zika virus (ZIKV), and Chikungunya virus (CHIKV). Bacillus thuringiensis (Bt) is widely used as a biopesticide, which produces Cry toxins for mosquito control. The Cry toxins bind mainly to important receptors, including alkaline phosphatase (ALP) and aminopeptidase-N (APN). This work investigated the function of a C-type lectin, CTLGA9, in A. aegypti in response to Cry toxins. Our results showed by far-western blot and ELISA methods that the CTLTGA9 protein interacted with brush border membrane vesicles (BBMVs) of A. aegypti larvae and with ALP1, APN, and Cry11Aa proteins. Furthermore, molecular docking showed overlapping binding sites in ALP1 and APN for binding to Cry11Aa and CTLGA9. The toxicity assays further demonstrated that CTLGA9 inhibited the larvicidal activity of Cry toxins. According to the results of molecular docking, CTLGA9 may compete with Cry11Aa for binding to ALP1 and APN receptors and thus decreases the mosquitocidal toxicity of Cry11Aa. Our results provide further insights into better understanding the mechanism of Cry toxins and help improve the Cry toxicity for mosquito control.
Collapse
Affiliation(s)
- Khadija Batool
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| | - Intikhab Alam
- Key Laboratory of Genetics, Breeding and Comprehensive Utilization of Crops, Ministry of Education, College of Crop Science , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , People's Republic of China
| | - Liang Jin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| | - Jin Xu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| | - Chenxu Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| | - Junxiang Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| | - Enjiong Huang
- Fujian International Travel Healthcare Center , 350001 Fuzhou , Fujian , People's Republic of China
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| | - Xiao-Qiang Yu
- Division of Cell Biology and Biophysics , University of Missouri , Kansas City , Missouri 64110 , United States
| | - Lingling Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Key Lab of Biopesticides and Chemical Biology, MOE , Fujian Agriculture and Forestry University , 350002 Fuzhou , Fujian , PR China
| |
Collapse
|
14
|
Zhao GH, Liu JN, Hu XH, Batool K, Jin L, Wu CX, Wu J, Chen H, Jiang XY, Yang ZH, Huang XH, Huang EJ, Yu XQ, Guan X, Zhang LL. Cloning, expression and activity of ATP-binding protein in Bacillus thuringiensis toxicity modulation against Aedes aegypti. Parasit Vectors 2019; 12:319. [PMID: 31238963 PMCID: PMC6593554 DOI: 10.1186/s13071-019-3560-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 06/09/2019] [Indexed: 11/17/2022] Open
Abstract
Background Bacillus thuringiensis israelensis (Bti) is a widely used mosquitocidal microbial pesticide due to its high toxicity. ATP-binding proteins (ABP) are prevalently detected in insects and are related to reaction against Bti toxins. However, the function of ABP in mosquito biocontrol is little known, especially in Aedes aegypti. Therefore, this study aimed to clarify the function of ABP in Ae. aegypti against Bti toxin. Results Aedes aegypti ABP (GenBank: XM_001661856.2) was cloned, expressed and purified in this study. Far-western blotting and ELISA were also carried out to confirm the interaction between ABP and Cry11Aa. A bioassay of Cry11Aa was performed both in the presence and absence of ABP, which showed that the mortality of Ae. aegypti is increased with an increase in ABP. Conclusions Our results suggest that ABP in Ae. aegypti can modulate the toxicity of Cry11Aa toxin to mosquitoes by binding to Bti toxin. This could not only enrich the mechanism of Bt toxin, but also provide more data for the biocontrol of this transmission vector.
Collapse
Affiliation(s)
- Guo-Hui Zhao
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Jian-Nan Liu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Xiao-Hua Hu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Khadija Batool
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Liang Jin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Chen-Xu Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Juan Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Hong Chen
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Xiao-Yan Jiang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zhao-Hui Yang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Xian-Hui Huang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - En-Jiong Huang
- Fujian International Travel HealthCare Center, Fuzhou, 350001, China
| | - Xiao-Qiang Yu
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China.,Division of Cell Biology and Biophysics, University of Missouri-Kansas City, Kansas City, MO, 64110, USA
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Ling-Ling Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & School of Life Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
| |
Collapse
|