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Lu T, Ji Y, Chang M, Zhang X, Wang Y, Zou Z. The accumulation of modular serine protease mediated by a novel circRNA sponging miRNA increases Aedes aegypti immunity to fungus. BMC Biol 2024; 22:7. [PMID: 38233907 PMCID: PMC10795361 DOI: 10.1186/s12915-024-01811-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 01/02/2024] [Indexed: 01/19/2024] Open
Abstract
BACKGROUND Mosquitoes transmit many infectious diseases that affect human health. The fungus Beauveria bassiana is a biological pesticide that is pathogenic to mosquitoes but harmless to the environment. RESULTS We found a microRNA (miRNA) that can modulate the antifungal immunity of Aedes aegypti by inhibiting its cognate serine protease. Fungal infection can induce the expression of modular serine protease (ModSP), and ModSP knockdown mosquitoes were more sensitive to B. bassiana infection. The novel miRNA-novel-53 is linked to antifungal immune response and was greatly diminished in infected mosquitoes. The miRNA-novel-53 could bind to the coding sequences of ModSP and impede its expression. Double fluorescence in situ hybridization (FISH) showed that this inhibition occurred in the cytoplasm. The amount of miRNA-novel-53 increased after miRNA agomir injection. This resulted in a significant decrease in ModSP transcript and a significant increase in mortality after fungal infection. An opposite effect was produced after antagomir injection. The miRNA-novel-53 was also knocked out using CRISPR-Cas9, which increased mosquito resistance to the fungus B. bassiana. Moreover, mosquito novel-circ-930 can affect ModSP mRNA by interacting with miRNA-novel-53 during transfection with siRNA or overexpression plasmid. CONCLUSIONS Novel-circ-930 affects the expression level of ModSP by a novel-circ-930/miRNA-novel-53/ModSP mechanism to modulate antifungal immunity, revealing new information on innate immunity in insects.
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Affiliation(s)
- Tengfei Lu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yannan Ji
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mengmeng Chang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoming Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanhong Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China.
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Zhang XF, Cui W, Wang MJ, Zhou Y, Fu TT, Jiang K, Hou YM, Tang BZ. Role of prophenoloxidase 1 from the beetle Octodonta nipae in melanized encapsulation of a wasp egg. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2024; 150:105082. [PMID: 37858613 DOI: 10.1016/j.dci.2023.105082] [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: 08/09/2023] [Revised: 10/14/2023] [Accepted: 10/15/2023] [Indexed: 10/21/2023]
Abstract
Exploring the function of the host immune system can help to understand the host-parasitoid interaction. Prophenoloxidase (PPO) is crucial in defensive melanization during the encapsulation of wasp eggs. However, the existence of multiple PPO sequences increases the difficulty of exploring the specific functions of individual PPOs. We previously identified three PPOs in the nipa palm hispid beetle, Octodonta nipae. Our current work showed that OnPPO1 and OnPPO2 possessed the typical characteristics of the type III copper family, but OnPPO3 lacked the conserved histidine residues, and its active sites were substituted with Gln. OnPPOs showed the highest expression in hemocytes, but OnPPO3 presented extremely low abundance compared with that of OnPPO1 and OnPPO2, and only OnPPO1 showed a quick response after wasp infection. OnPPO1 knockdown decreased the encapsulation index and inhibited melanization, whereas silencing of OnPPO3 appeared to have no adverse effect on encapsulation and melanization, and silencing of OnPPO2 presented low RNAi efficiency. Moreover, the cleavage of recombinant OnPPO1 produced a 62 kDa fragment with high PO activity. OnPPO1 could be produced by oenocytoids, granulocytes and plasmatocytes, and was distributed around wasp eggs during capsule formation. Overall, our results indicate that proteolytic cleavage of OnPPO1 plays key roles in the melanized encapsulation of wasp eggs. This finding illuminates the mechanism of PPO activation in this invasive beetle and provides guidance for its biological control.
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Affiliation(s)
- Xia-Fang Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Wen Cui
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Mou-Jun Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yan Zhou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Ting-Ting Fu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Kun Jiang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - You-Ming Hou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Bao-Zhen Tang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Provincial Key Laboratory of Insect Ecology, Department of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
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Jin Q, Wang Y, Hu Y, He Y, Xiong C, Jiang H. Serine protease homolog pairs CLIPA4-A6, A4-A7Δ, and A4-A12 act as cofactors for proteolytic activation of prophenoloxidase-2 and -7 in Anopheles gambiae. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 164:104048. [PMID: 38056530 PMCID: PMC10872527 DOI: 10.1016/j.ibmb.2023.104048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/20/2023] [Accepted: 11/29/2023] [Indexed: 12/08/2023]
Abstract
Phenoloxidase (PO) catalyzed melanization and other insect immune responses are mediated by serine proteases (SPs) and their noncatalytic homologs (SPHs). Many of these SP-like proteins have a regulatory clip domain and are called CLIPs. In most insects studied so far, PO precursors are activated by a PAP (i.e., PPO activating protease) and its cofactor of clip-domain SPHs. Although melanotic encapsulation is a well-known refractory mechanism of mosquitoes against malaria parasites, it is unclear if a cofactor is required for PPO activation. In Anopheles gambiae, CLIPA4 is 1:1 orthologous to Manduca sexta SPH2; CLIPs A5-7, A12-14, A26, A31, A32, E6, and E7 are 11:4 orthologous to M. sexta SPH1a, 1b, 4, and 101, SPH2 partners in the cofactors. Here we produced proCLIPs A4, A6, A7Δ, A12, and activated them with CLIPB9 or M. sexta PAP3. A. gambiae PPO2 and PPO7 were expressed in Escherichia coli for use as PAP substrates. CLIPB9 was mutated to CLIPB9Xa by including a Factor Xa cleavage site. CLIPA7Δ was a deletion mutant with a low complexity region removed. After PAP3 or CLIPB9Xa processing, CLIPA4 formed a high Mr complex with CLIPA6, A7Δ or A12, which assisted PPO2 and PPO7 activation. High levels of specific PO activity (55-85 U/μg for PO2 and 1131-1630 U/μg for PO7) were detected in vitro, indicating that cofactor-assisted PPO activation also occurs in this species. The cleavage sites and mechanisms for complex formation and cofactor function are like those reported in M. sexta and Drosophila melanogaster. In conclusion, these data suggest that the three (and perhaps more) SPHI-II pairs may form cofactors for CLIPB9-mediated activation of PPOs for melanotic encapsulation in A. gambiae.
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Affiliation(s)
- Qiao Jin
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Yang Wang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Yingxia Hu
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Yan He
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Chao Xiong
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA.
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Jin Q, Wang Y, Yin H, Jiang H. Two clip-domain serine protease homologs, cSPH35 and cSPH242, act as a cofactor for prophenoloxidase-1 activation in Drosophila melanogaster. Front Immunol 2023; 14:1244792. [PMID: 37781370 PMCID: PMC10540698 DOI: 10.3389/fimmu.2023.1244792] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/16/2023] [Indexed: 10/03/2023] Open
Abstract
Insect phenoloxidases (POs) catalyze phenol oxygenation and o-diphenol oxidation to form reactive intermediates that kill invading pathogens and form melanin polymers. To reduce their toxicity to host cells, POs are produced as prophenoloxidases (PPOs) and activated by a serine protease cascade as required. In most insects studied so far, PPO activating proteases (PAPs) generate active POs in the presence of a high Mr cofactor, comprising two serine protease homologs (SPHs) each with a Gly residue replacing the catalytic Ser of an S1A serine protease (SP). These SPHs have a regulatory clip domain at the N-terminus, like most of the SP cascade members including PAPs. In Drosophila, PPO activation and PO-catalyzed melanization have been examined in genetic analyses but it is unclear if a cofactor is required for PPO activation. In this study, we produced the recombinant cSPH35 and cSPH242 precursors, activated them with Manduca sexta PAP3, and confirmed their predicted role as a cofactor for Drosophila PPO1 activation by MP2 (i.e., Sp7). The cleavage sites and mechanisms for complex formation and cofactor function are highly similar to those reported in M. sexta. In the presence of high Mr complexes of the cSPHs, PO at a high specific activity of 260 U/μg was generated in vitro. To complement the in vitro analysis, we measured hemolymph PO activity levels in wild-type flies, cSPH35, and cSPH242 RNAi lines. Compared with the wild-type flies, only 4.4% and 18% of the control PO level (26 U/μl) was detected in the cSPH35 and cSPH242 knockdowns, respectively. Consistently, percentages of adults with a melanin spot at the site of septic pricking were 82% in wild-type, 30% in cSPH35 RNAi, and 53% in cSPH242 RNAi lines; the survival rate of the control (45%) was significantly higher than those (30% and 15%) of the two RNAi lines. These data suggest that Drosophila cSPH35 and cSPH242 are components of a cofactor for MP2-mediated PPO1 activation, which are indispensable for early melanization in adults.
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Affiliation(s)
| | | | | | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK, United States
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Will I, Attardo GM, de Bekker C. Multiomic interpretation of fungus-infected ant metabolomes during manipulated summit disease. Sci Rep 2023; 13:14363. [PMID: 37658067 PMCID: PMC10474057 DOI: 10.1038/s41598-023-40065-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 08/03/2023] [Indexed: 09/03/2023] Open
Abstract
Camponotus floridanus ants show altered behaviors followed by a fatal summiting phenotype when infected with manipulating Ophiocordyceps camponoti-floridani fungi. Host summiting as a strategy to increase transmission is also observed with parasite taxa beyond fungi, including aquatic and terrestrial helminths and baculoviruses. The drastic phenotypic changes can sometimes reflect significant molecular changes in gene expression and metabolite concentrations measured in manipulated hosts. Nevertheless, the underlying mechanisms still need to be fully characterized. To investigate the small molecules producing summiting behavior, we infected C. floridanus ants with O. camponoti-floridani and sampled their heads for LC-MS/MS when we observed the characteristic summiting phenotype. We link this metabolomic data with our previous genomic and transcriptomic data to propose mechanisms that underlie manipulated summiting behavior in "zombie ants." This "multiomic" evidence points toward the dysregulation of neurotransmitter levels and neuronal signaling. We propose that these processes are altered during infection and manipulation based on (1) differential expression of neurotransmitter synthesis and receptor genes, (2) altered abundance of metabolites and neurotransmitters (or their precursors) with known behavioral effects in ants and other insects, and (3) possible suppression of a connected immunity pathway. We additionally report signals for metabolic activity during manipulation related to primary metabolism, detoxification, and anti-stress protectants. Taken together, these findings suggest that host manipulation is likely a multi-faceted phenomenon, with key processes changing at multiple levels of molecular organization.
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Affiliation(s)
- I Will
- Biology Department, University of Central Florida, Orlando, USA.
| | - G M Attardo
- Entomology and Nematology Department, University of California-Davis, Davis, USA
| | - C de Bekker
- Biology Department, University of Central Florida, Orlando, USA.
- Biology Department, Utrecht University, Utrecht, The Netherlands.
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Zhao L, Niu J, Feng D, Wang X, Zhang R. Immune functions of pattern recognition receptors in Lepidoptera. Front Immunol 2023; 14:1203061. [PMID: 37398667 PMCID: PMC10312389 DOI: 10.3389/fimmu.2023.1203061] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 06/05/2023] [Indexed: 07/04/2023] Open
Abstract
Pattern recognition receptors (PRRs), as the "sensors" in the immune response, play a prominent role in recognizing pathogen-associated molecular patterns (PAMPs) and initiating an effective defense response to pathogens in Lepidoptera. It is becoming increasingly clear that damage-associated molecular patterns (DAMPs) normally play a physiological role within cells; however, when exposed to extracellular, they may become "part-time" critical signals of the immune response. Based on research in recent years, we review herein typical PRRs of Lepidoptera, including peptidoglycan recognition protein (PGRP), gram-negative binding protein (GNBP), β-1,3-glucan recognition protein (βGRP), C-type lectin (CTL), and scavenger receptor (SR). We also outline the ways in which DAMPs participate in the immune response and the correlation between PRRs and immune escape. Taken together, these findings suggest that the role of PRRs in insect innate immunity may be much greater than expected and that it is possible to recognize a broader range of signaling molecules.
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Affiliation(s)
- Lin Zhao
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
| | - Jinlan Niu
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
| | - Disong Feng
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
| | - Xialu Wang
- School of Medical Devices, Shenyang Pharmaceutical University, Shenyang, China
| | - Rong Zhang
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
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7
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Wang Z, Luo J, Feng K, Zhou Y, Tang F. Prophenoloxidase of Odontotermes formosanus (Shiraki) (Blattodea: Termitidae) Is a Key Gene in Melanization and Has a Defensive Role during Bacterial Infection. Int J Mol Sci 2022; 24:ijms24010406. [PMID: 36613850 PMCID: PMC9820534 DOI: 10.3390/ijms24010406] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Melanization mediated by the prophenoloxidase (PPO)-activating system is an important innate immunity to fight pathogens in insects. In this study, the in vitro time-dependent increase in the intensity of melanization and phenoloxidase (PO) activity from the hemolymph of Odontotermes formosanus (Shiraki) challenged by pathogenic bacteria was detected. PPO is one of the key genes in melanization pathway, whereas the molecular characteristics and functions of O. formosanus PPO are unclear. The OfPPO gene was cloned and characterized. The open reading frame of OfPPO is 2085 bp in length and encodes a 79.497 kDa protein with 694 amino acids. A BLASTx search and phylogenetic analyses revealed that OfPPO shares a high degree of homology to the Blattodea PPOs. Moreover, real-time fluorescent quantitative PCR analysis showed that OfPPO is ubiquitously expressed in all castes and tissues examined, with the highest expression in workers and variable expression patterns in tissues of different termite castes. Furthermore, the expression of OfPPO was significantly induced in O. formosanus infected by pathogenic bacteria. Intriguingly, in combination with silencing of OfPPO expression, pathogenic bacteria challenge caused greatly increased mortality of O. formosanus. These results suggest that OfPPO plays a role in defense against bacteria and highlight the novel termite control strategy combining pathogenic bacteria application with termite PPO silencing.
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Affiliation(s)
- Zhiqiang Wang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China
| | - Jian Luo
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China
| | - Kai Feng
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China
| | - Yujingyun Zhou
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China
| | - Fang Tang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China
- Correspondence: ; Tel.: +86-138-1396-6269
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Yan Y, Jia MH, Le ZJ, Xu KK, Li C, Yang WJ. Four peptidoglycan recognition proteins are indispensable for antibacterial immunity in the cigarette beetle Lasioderma serricorne (Fabricius). Int J Biol Macromol 2022; 220:1212-1220. [PMID: 36049566 DOI: 10.1016/j.ijbiomac.2022.08.162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/14/2022] [Accepted: 08/23/2022] [Indexed: 12/29/2022]
Abstract
The peptidoglycan recognition protein (PGRP), an important pattern recognition receptor of insects, is significant for reducing innate immunity and effective pest control. We cloned four PGRP genes (LsPGRP-LB, LsPGRP-LB1, LsPGRP-LE, and LsPGRP-SC2) from the cigarette beetle, Lasioderma serricorne (Fabricius), which encoded proteins of 216, 197, 317, and 190 amino acids, respectively. Three LsPGRPs were predominantly expressed in the larval and pupal stages, whereas LsPGRP-LE displayed high expression in adults. All the four LsPGRPs genes were highly expressed in the midgut and integument. Pathogen inoculation revealed that the four LsPGRPs actively responded to Escherichia coli and its peptidoglycan. The transcription levels of LsPGRP-LE and LsPGRP-SC2 increased significantly after Staphylococcus aureus stimulation. RNA interference-mediated knockdown of the four LsPGRPs led to increased larval mortality when challenged by E. coli, and the expression of four antimicrobial peptide genes (LsCole, LsAtt2, LsDef1 and LsDef2) had a significant decrease. Higher mortality and lower AMP expression were also observed in L. serricorne under S. aureus infection after silencing LsPGRP-LE and LsPGRP-SC2. Our results suggest that the four LsPGRP genes play important and distinct regulatory roles in the antibacterial defense response of L. serricorne.
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Affiliation(s)
- Yi Yan
- Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region, College of Biology and Environmental Engineering, Guiyang University, Guiyang 550005, China
| | - Ming-Huan Jia
- Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region, College of Biology and Environmental Engineering, Guiyang University, Guiyang 550005, China
| | - Zhi-Jun Le
- Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region, College of Biology and Environmental Engineering, Guiyang University, Guiyang 550005, China
| | - Kang-Kang Xu
- Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region, College of Biology and Environmental Engineering, Guiyang University, Guiyang 550005, China
| | - Can Li
- Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region, College of Biology and Environmental Engineering, Guiyang University, Guiyang 550005, China
| | - Wen-Jia Yang
- Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region, College of Biology and Environmental Engineering, Guiyang University, Guiyang 550005, China.
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Wang Q, Yin M, Yuan C, Liu X, Jiang H, Wang M, Zou Z, Hu Z. The Micrococcus luteus infection activates a novel melanization pathway of cSP10, cSP4, and cSP8 in Helicoverpa armigera. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 147:103775. [PMID: 35504546 DOI: 10.1016/j.ibmb.2022.103775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/13/2022] [Accepted: 04/23/2022] [Indexed: 06/14/2023]
Abstract
Melanization is a key immune response mediated by serine protease (SP) cascade in insects. Multiple SP pathways exist in different species and it is unclear how conserved these cascades are. The cotton bollworm Helicoverpa armigera is a major worldwide agricultural pest. We reported a conserved melanization pathway in this species, which consists of SP41, cSP1, and cSP6. In this study, we attempted to identify an insect pathogen that elicits the cascade and test whether or not there are other SP cascades in H. armigera. After Micrococcus luteus, Enterobacter cloacae, Beauveria bassiana, or Helicoverpa armigera nucleopolyhedrovirus were injected into larvae, pathogen-induced hemolymph samples were collected for in vitro biochemical assays, which failed to detect proSP41 or procSP1 activation. In contrast, we found that procSP4, a protein proposed to participate in H. armigera melanization, was activated in M. luteus infected hemolymph. We further revealed that cSP8 was a prophenoloxidase (PPO) activating protease downstream of cSP4, and cSP4 was activated by cSP10. The pathway of cSP10-cSP4-cSP8 activated PPO in vitro. Efficiently cleaved procSPH11 and procSPH50 by cSP8 substantially enhanced phenoloxidase activity, suggesting they work together as a cofactor for cSP8 mediated PPO activation. Hemolymph from larvae challenged with M. luteus or its peptidoglycan effectively activated procSP10. Collectively, these results revealed a new PPO activation cascade specifically triggered by the bacterium. In addition, we found that the PPO activation cascades in H. armigera and Manduca sexta are conserved.
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Affiliation(s)
- Qianran Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mengyi Yin
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chuanfei Yuan
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Xijia Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Manli Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Zhihong Hu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
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10
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Ji Y, Lu T, Zou Z, Wang Y. Aedes aegypti CLIPB9 activates prophenoloxidase-3 in the presence of CLIPA14 after fungal infection. Front Immunol 2022; 13:927322. [PMID: 35967454 PMCID: PMC9365933 DOI: 10.3389/fimmu.2022.927322] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
Melanization is an integral part of the insect defense system and is often induced by pathogen invasion. Phenoloxidases (POs) are critical enzymes that catalyze melanin formation. PO3 is associated with the antifungal response of the mosquito, Aedes aegypti, but the molecular mechanism of the prophenoloxidase-3 (PPO3) activation is unclear. Here we report that PPO3 cleavage activation is mediated by a clip-domain serine protease, CLIPB9. We purified recombinant CLIPB9 and found that it cleaved PPO3 and increased PO activity in the hemolymph. We then identified CLIPA14 (a serine protease homolog) by co-immunoprecipitation using anti-CLIPB9 antibody. After being cleaved by CLIPB9, Ae. aegypti CLIPA14 acted as a cofactor for PPO3 activation. In addition, dsRNA co-silencing of CLIPB9 and CLIPA14 genes reduced melanization after infection with the entomopathogen, Beauveria bassiana, making the adult mosquitoes more sensitive to fungal infection. These results illustrate the roles of CLIPB9 and CLIPA14 in the PPO activation pathway and revealed the complexity of the upstream serine protease network controlling melanization.
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Affiliation(s)
- Yannan Ji
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Tengfei Lu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Yanhong Wang, ; Zhen Zou,
| | - Yanhong Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Yanhong Wang, ; Zhen Zou,
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11
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Zhang R, Zhang XF, Chi Y, Xu Y, Chen H, Guo Z, Wei T. Nucleoprotein of a Rice Rhabdovirus Serves as the Effector to Attenuate Hemolymph Melanization and Facilitate Viral Persistent Propagation in its Leafhopper Vector. Front Immunol 2022; 13:904244. [PMID: 35655780 PMCID: PMC9152149 DOI: 10.3389/fimmu.2022.904244] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 04/20/2022] [Indexed: 11/13/2022] Open
Abstract
Melanization in the hemolymph of arthropods is a conserved defense strategy against infection by invading pathogens. Numerous plant viruses are persistently transmitted by insect vectors, and must overcome hemolymph melanization. Here, we determine that the plant rhabdovirus rice stripe mosaic virus (RSMV) has evolved to evade the antiviral melanization response in the hemolymph in leafhopepr vectors. After virions enter vector hemolymph cells, viral nucleoprotein N is initially synthesized and directly interacts with prophenoloxidase (PPO), a core component of the melanization pathway and this process strongly activates the expression of PPO. Furthermore, such interaction could effectively inhibit the proteolytic cleavage of the zymogen PPO to active phenoloxidase (PO), finally suppressing hemolymph melanization. The knockdown of PPO expression or treatment with the PO inhibitor also suppresses hemolymph melanization and causes viral excessive accumulation, finally causing a high insect mortality rate. Consistent with this function, microinjection of N into leafhopper vectors attenuates melanization and promotes viral infection. These findings demonstrate that RSMV N serves as the effector to attenuate hemolymph melanization and facilitate viral persistent propagation in its insect vector. Our findings provide the insights in the understanding of ongoing arms race of insect immunity defense and viral counter-defense.
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Affiliation(s)
| | | | | | | | | | | | - Taiyun Wei
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
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12
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Liu WT, Chen CC, Ji DD, Tu WC. The cecropin-prophenoloxidase regulatory mechanism is a cross-species physiological function in mosquitoes. iScience 2022; 25:104478. [PMID: 35712072 PMCID: PMC9194137 DOI: 10.1016/j.isci.2022.104478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 04/06/2022] [Accepted: 05/25/2022] [Indexed: 11/06/2022] Open
Abstract
This study's aim was to investigate whether the cecropin-prophenoloxidase regulatory mechanism is a cross-species physiological function among mosquitoes. BLAST and phylogenetic analysis revealed that three mosquito cecropin Bs, namely Aedes albopictus cecropin B (Aalcec B), Armigeres subalbatus cecropin B2 (Ascec B2), and Culex quinquefasciatus cecropin B1 (Cqcec B1), play crucial roles in cuticle formation during pupal development via the regulation of prophenoloxidase 3 (PPO 3). The effects of cecropin B knockdown were rescued in a cross-species manner by injecting synthetic cecropin B peptide into pupae. Further investigations showed that these three cecropin B peptides bind to TTGG(A/C)A motifs within each of the PPO 3 DNA fragments obtained from these three mosquitoes. These results suggest that Aalcec B, Ascec B2, and Cqcec B1 each play an important role as a transcription factor in cuticle formation and that similar cecropin-prophenoloxidase regulatory mechanisms exist in multiple mosquito species. Cecropin B is able to regulate PPO 3 expression in the pupae Cecropin B binds to TTGG(A/C)A motifs within the PPO 3 DNA The knockdown of cecropin B was rescued by sequence-similar cecropin B peptides The cecropin B-prophenoloxidase 3 regulatory mechanism is conserved in mosquitoes
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13
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Cerenius L, Söderhäll K. Immune properties of invertebrate phenoloxidases. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 122:104098. [PMID: 33857469 DOI: 10.1016/j.dci.2021.104098] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/12/2021] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
Melanin production from different types of phenoloxidases (POs) confers immunity from a variety of pathogens ranging from viruses and microorganisms to parasites. The arthropod proPO expresses a variety of activities including cytokine, opsonin and microbiocidal activities independent of and even without melanin production. Proteolytic processing of proPO and its activating enzyme gives rise to several peptide fragments with a variety of separate activities in a process reminiscent of vertebrate complement system activation although proPO bears no sequence similarity to vertebrate complement factors. Pathogens influence proPO activation and thereby what types of immune effects that will be produced. An increasing number of specialised pathogens - from parasites to viruses - have been identified who can synthesise compounds specifically aimed at the proPO-system. In invertebrates outside the arthropods phylogenetically unrelated POs are participating in melanization reactions obviously aimed at intruders and/or aberrant tissues.
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Affiliation(s)
- Lage Cerenius
- Department of Organismal Biology,Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden.
| | - Kenneth Söderhäll
- Department of Organismal Biology,Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden
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14
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Intraspecific variation in immune gene expression and heritable symbiont density. PLoS Pathog 2021; 17:e1009552. [PMID: 33901257 PMCID: PMC8102006 DOI: 10.1371/journal.ppat.1009552] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 05/06/2021] [Accepted: 04/09/2021] [Indexed: 12/21/2022] Open
Abstract
Host genetic variation plays an important role in the structure and function of heritable microbial communities. Recent studies have shown that insects use immune mechanisms to regulate heritable symbionts. Here we test the hypothesis that variation in symbiont density among hosts is linked to intraspecific differences in the immune response to harboring symbionts. We show that pea aphids (Acyrthosiphon pisum) harboring the bacterial endosymbiont Regiella insecticola (but not all other species of symbionts) downregulate expression of key immune genes. We then functionally link immune expression with symbiont density using RNAi. The pea aphid species complex is comprised of multiple reproductively-isolated host plant-adapted populations. These ‘biotypes’ have distinct patterns of symbiont infections: for example, aphids from the Trifolium biotype are strongly associated with Regiella. Using RNAseq, we compare patterns of gene expression in response to Regiella in aphid genotypes from multiple biotypes, and we show that Trifolium aphids experience no downregulation of immune gene expression while hosting Regiella and harbor symbionts at lower densities. Using F1 hybrids between two biotypes, we find that symbiont density and immune gene expression are both intermediate in hybrids. We propose that in this system, Regiella symbionts are suppressing aphid immune mechanisms to increase their density, but that some hosts have adapted to prevent immune suppression in order to control symbiont numbers. This work therefore suggests that antagonistic coevolution can play a role in host-microbe interactions even when symbionts are transmitted vertically and provide a clear benefit to their hosts. The specific immune mechanisms that we find are downregulated in the presence of Regiella have been previously shown to combat pathogens in aphids, and thus this work also highlights the immune system’s complex dual role in interacting with both beneficial and harmful microbes. Insects frequently form beneficial partnerships with heritable microbes that are passed from mothers to offspring. Natural populations exhibit a great deal of variation in the frequency of heritable microbes and in the within-host density of these infections. Uncovering the mechanisms underlying variation in host-microbe interactions is key to understanding how they evolve. We study a model host-microbe interaction: the pea aphid and a heritable bacterium that makes aphids resistant to fungal pathogens. We show that aphids harboring bacteria show sharply reduced expression of innate immune system genes, and that this leads to increased densities of symbionts. We further show that populations of aphids that live on different species of plants vary in differential immune gene expression and in the density of their symbiont infections. This study contributes to our mechanistic understanding of an important model of host-microbe symbiosis and suggests that hosts and heritable microbes are evolving antagonistically. This work also sheds light on how invertebrate immune systems evolve to manage the complex task of combatting harmful pathogens while accommodating potentially beneficial microbes.
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15
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Li ZQ, Song XH, Wang M, Wang S, Huang GH. Melanization induced by Heliothis virescens ascovirus 3h promotes viral replication. INSECT SCIENCE 2021; 28:472-484. [PMID: 32243720 DOI: 10.1111/1744-7917.12786] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/19/2020] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
Melanization is an important innate immune defense mechanism of insects, which can kill invading pathogens. Most pathogens, for their survival and reproduction, inhibit the melanization of the host. Interestingly, our results suggested that after infection with Heliothis virescens ascovirus 3h (HvAV-3h), the speed of melanization in infected Spodoptera exigua larval hemolymph was accelerated and that the phenoloxidase (PO) activity of hemolymph in larvae infected with HvAV-3h increased significantly (1.20-fold at 96 hpi, 1.52-fold at 120 hpi, 1.23-fold at 144 hpi, 1.12-fold at 168 hpi). The transcription level of the gene encoding S. exigua prophenoloxidase-1 (SePPO-1 gene) was upregulated dramatically in the fat body during the middle stage of infection. In addition, when melanization was inhibited or promoted, the replication of HvAV-3h was inhibited or promoted, respectively. In conclusion, infection with HvAV-3h can markedly induce melanization in the middle stage of infection, and melanization is helpful for HvAV-3h viral replication.
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Affiliation(s)
- Zi-Qi Li
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, China
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Xiao-Hui Song
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, China
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Min Wang
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, China
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Shu Wang
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, China
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Guo-Hua Huang
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, China
- College of Plant Protection, Hunan Agricultural University, Changsha, China
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16
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Chang MM, Wang YH, Yang QT, Wang XL, Wang M, Raikhel AS, Zou Z. Regulation of antimicrobial peptides by juvenile hormone and its receptor, Methoprene-tolerant, in the mosquito Aedes aegypti. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2021; 128:103509. [PMID: 33264664 DOI: 10.1016/j.ibmb.2020.103509] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 11/09/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
The trade-off between reproduction and immunity has been established for a number of insect species. However, the regulatory mechanisms governing this event is not well understood. In the mosquito Aedes aegypti, the vector of dangerous human arboviral diseases, juvenile hormone (JH) is required for the female post-eclosion development and reproductive maturation. In this study, we have revealed the JH negative effect on the expression of immunity-related genes, such as antimicrobial peptides (AMPs), during the post-eclosion phase of the female mosquito gonadotrophic reproductive cycle. Mosquitoes treated with JH became more sensitive to microbial infection. Mosquitoes subjected to the RNA interference knockdown (RNAi) of the JH receptor, Methoprene-tolerant (Met), showed increased expression of several AMP genes. Met binds to the E-box-like recognition motifs in the regulatory region of the diptericin (Dpt) gene, indicating that JH can suppress the Dpt gene expression through its receptor Met. Hence, JH is involved in the modulation of immune responses during the post-eclosion phase of reproduction. The RNAi knockdown of the peptidoglycan recognition protein (PGRP-LC) led to a significant reduction of the Dpt transcript level, indicating the PGRP-LC activating role on this AMP gene. Thus, Dpt appeared to be under the dual regulation of both the JH and the immune deficiency (IMD) signaling pathways. Our study provides a better understanding of how JH regulates insect immunity in adult mosquitoes.
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Affiliation(s)
- Meng-Meng Chang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yan-Hong Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qing-Tai Yang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xue-Li Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mao Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Alexander S Raikhel
- Department of Entomology and Institute for Integrative Genome Biology, University of California, Riverside, CA, 92521, USA
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China; Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, 311300, China.
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17
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Bitencourt RDOB, Salcedo-Porras N, Umaña-Diaz C, da Costa Angelo I, Lowenberger C. Antifungal immune responses in mosquitoes (Diptera: Culicidae): A review. J Invertebr Pathol 2020; 178:107505. [PMID: 33238166 DOI: 10.1016/j.jip.2020.107505] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/27/2020] [Accepted: 11/17/2020] [Indexed: 02/08/2023]
Abstract
Mosquitoes transmit many parasites and pathogens to humans that cause significant morbidity and mortality. As such, we are constantly looking for new methods to reduce mosquito populations, including the use of effective biological controls. Entomopathogenic fungi are excellent candidate biocontrol agents to control mosquitoes. Understanding the complex ecological, environmental, and molecular interactions between hosts and pathogens are essential to create novel, effective and safe biocontrol agents. Understanding how mosquitoes recognize and eliminate pathogens such as entomopathogenic fungi may allow us to create insect-order specific biocontrol agents to reduce pest populations. Here we summarize the current knowledge of fungal infection, colonization, development, and replication within mosquitoes and the innate immune responses of the mosquitoes towards the fungal pathogens, emphasizing those features required for an effective mosquito biocontrol agent.
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Affiliation(s)
- Ricardo de Oliveira Barbosa Bitencourt
- Program in Veterinary Science, Institute of Veterinary Science, Rural Federal University of Rio de Janeiro, Seropédica, RJ, Brazil; Centre for Cell Biology, Development and Disease, Department of Biological Sciences, Simon Fraser University, Burnaby BC V5A 1S6, British Columbia, Canada.
| | - Nicolas Salcedo-Porras
- Centre for Cell Biology, Development and Disease, Department of Biological Sciences, Simon Fraser University, Burnaby BC V5A 1S6, British Columbia, Canada
| | - Claudia Umaña-Diaz
- Centre for Cell Biology, Development and Disease, Department of Biological Sciences, Simon Fraser University, Burnaby BC V5A 1S6, British Columbia, Canada
| | - Isabele da Costa Angelo
- Department of Epidemiology and Public Health, Veterinary Institute, Rural Federal University of Rio de Janeiro, Seropédica, RJ, Brazil
| | - Carl Lowenberger
- Centre for Cell Biology, Development and Disease, Department of Biological Sciences, Simon Fraser University, Burnaby BC V5A 1S6, British Columbia, Canada.
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18
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A Plant Virus Ensures Viral Stability in the Hemolymph of Vector Insects through Suppressing Prophenoloxidase Activation. mBio 2020; 11:mBio.01453-20. [PMID: 32817105 PMCID: PMC7439478 DOI: 10.1128/mbio.01453-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Large ratios of vector-borne plant viruses circulate in the hemolymph of their vector insects before entering the salivary glands to be transmitted to plants. The stability of virions in the hemolymph is vital in this process. Activation of the proteolytic prophenoloxidase (PPO) to produce active phenoloxidase (PO) is one of the major innate immune pathways in insect hemolymph. How a plant virus copes with the PPO immune reaction in its vector insect remains unclear. Here, we report that the PPO affects the stability of rice stripe virus (RSV), a notorious rice virus, in the hemolymph of a vector insect, the small brown planthopper. RSV suppresses PPO activation using viral nonstructural protein. Once the level of PO activity is elevated, RSV is melanized and eliminated from the hemolymph. Our work gives valuable clues for developing novel strategies for controlling the transmission of vector-borne plant viruses. Most plant viruses require vector insects for transmission. Viral stability in the hemolymph of vector insects is a prerequisite for successful transmission of persistent plant viruses. However, knowledge of whether the proteolytic activation of prophenoloxidase (PPO) affects the stability of persistent plant viruses remains elusive. Here, we explored the interplay between rice stripe virus (RSV) and the PPO cascade of the vector small brown planthopper. Phenoloxidase (PO) activity was suppressed by RSV by approximately 60%. When the PPO cascade was activated, we found distinct melanization around RSV particles and serious damage to viral stability in the hemolymph. Viral suppression of PO activity was derived from obstruction of proteolytic cleavage of PPOs by binding of the viral nonstructural protein NS3. These results indicate that RSV attenuates the PPO response to ensure viral stability in the hemolymph of vector insects. Our research provides enlightening cues for controlling the transmission of vector-borne viruses.
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19
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Wang Q, Yin M, Yuan C, Liu X, Hu Z, Zou Z, Wang M. Identification of a Conserved Prophenoloxidase Activation Pathway in Cotton Bollworm Helicoverpa armigera. Front Immunol 2020; 11:785. [PMID: 32431706 PMCID: PMC7215089 DOI: 10.3389/fimmu.2020.00785] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 04/07/2020] [Indexed: 01/03/2023] Open
Abstract
Melanization is a prominent insect humoral response for encapsulation of and killing invading pathogens. It is mediated by a protease cascade composed of a modular serine protease (SP), and clip domain SPs (cSPs), which converts prophenoloxidase (PPO) into active phenoloxidase (PO). To date, melanization pathway in cotton bollworm Helicoverpa armigera, an important agricultural pest, remains largely unclear. To biochemically reconstitute the pathway in vitro, the putative proteases along with modified proteases containing the factor Xa cleavage site were expressed by Drosophila S2 cell expression system. Purified recombinant proteins were used to examine their role in activating PPO. It is revealed that cascade is initiated by a modular SP-SP41, followed by cSP1 and cSP6. The three-step SP41/cSP1/cSP6 cascade could further activate PPO, and the PO activity was significantly enhanced in the presence of two cSP homologs (cSPHs), cSPH11 and cSPH50, suggesting the latter are cofactors for PPO activation. Moreover, baculovirus infection was efficiently blocked by the reconstituted PPO activation cascade, and the effect was boosted by cSPH11 and cSPH50. Taken together, we unraveled a conserved PPO activation cascade in H. armigera, which is similar to that exists in lepidopteran biochemical model Manduca sexta and highlighted its role in antagonizing viral infection.
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Affiliation(s)
- Qianran Wang
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Mengyi Yin
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Chuanfei Yuan
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xijia Liu
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Zhihong Hu
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Zhen Zou
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China.,State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Key Laboratory of Tropical Translational Medicine, Laboratory of Medicine, School of Tropical Medicine, Ministry of Education, Hainan Medical University, Haikou, China
| | - Manli Wang
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
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20
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Abstract
Insects possess powerful immune systems that have evolved to defend against wounding and environmental pathogens such as bacteria, fungi, protozoans, and parasitoids. This surprising sophistication is accomplished through the activation of multiple immune pathways comprised of a large array of components, many of which have been identified and studied in detail using both genetic manipulations and traditional biochemical techniques. Recent advances indicate that certain pathways activate arrays of proteins that interact to form large functional complexes. Here we discuss three examples from multiple insects that exemplify such processes, including pathogen recognition, melanization, and coagulation. The functionality of each depends on integrating recognition with the recruitment of immune effectors capable of healing wounds and destroying pathogens. In both melanization and coagulation, protein interactions also appear to be essential for enzymatic activities tied to the formation of melanin and for the recruitment of hemocytes. The importance of these immune complexes is highlighted by the evolution of mechanisms in pathogens to disrupt their formation, an example of which is provided. While technically difficult to study, and not always readily amenable to dissection through genetics, modern mass spectrometry has become an indispensable tool in the study of these higher-order protein interactions. The formation of immune complexes should be viewed as an essential and emerging frontier in the study of insect immunity.
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21
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Xu L, Ma L, Wang W, Li L, Lu Z. Phenoloxidases are required for the pea aphid's defence against bacterial and fungal infection. INSECT MOLECULAR BIOLOGY 2019; 28:176-186. [PMID: 30182435 DOI: 10.1111/imb.12536] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The pea aphid, Acyrthosiphon pisum, has an incomplete immune system compared to those of other insect species; some conserved components and pathways in other species are missing in its genome. As a core component of the insect immune system, prophenoloxidase (PPO) genes are retained in the pea aphid. Early studies have also shown the presence of phenoloxidase activity in specific tissues or cells in the pea aphid and suggested its involvement in response to immune challenges. In this study, we knocked down the expression of PPO genes in the pea aphid using double-stranded RNA-based interference, and quantitative PCR analysis and an enzyme activity assay confirmed our success in the PPO gene knockdown. In bacterial and fungal infection experiments, we observed that the knockdown of PPO resulted in more live bacterial cells and fungal spores in the body of the aphids and higher mortality of the aphids after infection. Our study provides evidence supporting a critical role of PPO in the defence of the pea aphid.
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Affiliation(s)
- L Xu
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - L Ma
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - W Wang
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - L Li
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Z Lu
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Northwest A&F University, Yangling, Shaanxi, China
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22
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Wu K, Han F, Yuan Y, Liu Y, Ling E, Wang Q, Huang W. Effect of the insect phenoloxidase on the metabolism of l-DOPA. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2018; 98:e21457. [PMID: 29570828 DOI: 10.1002/arch.21457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Insect prophenoloxidase (PPO) induces melanization around pathogens. Before melanization, PPO is cleaved into phenoloxidase (PO) by serine proteases. Insect PPO can also be activated by exogenous proteases secreted by pathogens as well as by other compounds, such as ethanol and cetylpyridinium chloride (CPC). However, the effect of these activators on the activity of PO is unclear. In this study, the insect endogenous serine protease AMM1, α-chymotrypsin, and ethanol were used to activate recombinant Drosophila PPO1 (rPPO1), and the PO activity differed depending on the activator applied. The PO-induced intermediates during melanization also varied markedly in their numbers and abundances. Therefore, this study indicates that the mechanism of PPO activation influences PO activity. It also suggests that PO-induced different intermediates may affect the antibacterial activity during melanization due to their toxicity.
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Affiliation(s)
- Kai Wu
- College of Life Sciences, Shangrao Normal University, Shangrao, China
- Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Fang Han
- Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Yi Yuan
- Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Yining Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Erjun Ling
- Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Qian Wang
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| | - Wuren Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
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Ramirez JL, Muturi EJ, Dunlap C, Rooney AP. Strain-specific pathogenicity and subversion of phenoloxidase activity in the mosquito Aedes aegypti by members of the fungal entomopathogenic genus Isaria. Sci Rep 2018; 8:9896. [PMID: 29967469 PMCID: PMC6028645 DOI: 10.1038/s41598-018-28210-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 06/13/2018] [Indexed: 12/16/2022] Open
Abstract
Development of alternative vector control strategies are becoming more pressing given the rapid evolution of insecticide resistance and the rise of vector borne pathogens affecting public health such as dengue, chikungunya and Zika. Fungal-based biopesticides are promising alternatives to synthetic insecticides because they are ecofriendly and are highly effective at infecting insects through contact. This study evaluated the susceptibility of the yellow fever mosquito Ae. aegypti to a range of entomopathogenic fungal strains from the genus Isaria. We observed a diverse variation in the virulence of the Isaria strains tested, with two strains showing high pathogenicity towards adult mosquitoes. Mosquito susceptibility to fungal infection was further corroborated through the molecular quantification of fungal loads and the transcript evaluation of a fungal-specific pathogen recognition molecule in the mosquito body. Moreover, quantitative analysis of transcript abundance coupled with enzymatic assays revealed strain-specific subversion of the melanization cascade, an important immune response component. Our study contributes critical insights for a better understanding of fungal-mosquito interactions.
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Affiliation(s)
- José L Ramirez
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, Illinois, USA.
| | - Ephantus J Muturi
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, Illinois, USA
| | - Christopher Dunlap
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, Illinois, USA
| | - Alejandro P Rooney
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, Illinois, USA
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24
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Cheng Y, Lin Z, Wang JM, Xing LS, Xiong GH, Zou Z. CTL14, a recognition receptor induced in late stage larvae, modulates anti-fungal immunity in cotton bollworm Helicoverpa armigera. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 84:142-152. [PMID: 29453998 DOI: 10.1016/j.dci.2018.02.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 02/09/2018] [Accepted: 02/10/2018] [Indexed: 06/08/2023]
Abstract
C-type lectin (CTL) is usually considered as pattern recognition receptors in insect innate immunity. Here we found that CTL14 of Helicoverpa armigera was only activated in the fifth instar larvae not in the second instar by entomopathogen Beauveria bassiana infection. Recombinant CTL14 protein was found to form aggregates with zymosan and B. bassiana in vitro. Immunoprecipitation studies demonstrated that CTL14 interacted with serine proteinases (SP), serine proteinase inhibitor (serpin), prophenoloxidases (PPO) and vitellogenin (Vg) in the larval hemolymph. Furthermore, depletion of CTL14 using dsRNA led to dramatic decrease in the expression level of PPO1. Additionally, CTL14 depleted H. armigera decreased the resistance to fungal challenge. Taken together, our study showed the direct involvement of CTL14 in the anti-fungal immunity of H. armigera, which further explained the stronger immune responses in the fifth instar compared to the second instar larvae.
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Affiliation(s)
- Yang Cheng
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhe Lin
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ju-Mei Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Long-Sheng Xing
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Guang-Hua Xiong
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; School of Life Sciences, Jinggangshan University, Ji'an, 343009, China
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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Wang YH, Chang MM, Wang XL, Zheng AH, Zou Z. The immune strategies of mosquito Aedes aegypti against microbial infection. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 83:12-21. [PMID: 29217264 DOI: 10.1016/j.dci.2017.12.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/30/2017] [Accepted: 12/03/2017] [Indexed: 06/07/2023]
Abstract
Yellow fever mosquito Aedes aegypti transmits many devastating arthropod-borne viruses (arboviruses), such as dengue virus, yellow fever virus, Chikungunya virus, and Zika virus, which cause great concern to human health. Mosquito control is an effective method to block the spread of infectious diseases. Ae. aegypti uses its innate immune system to fight against arboviruses, parasites, and fungi. In this review, we briefly summarize the recent findings in the immune response of Ae. aegypti against arboviral and entomopathogenic infections. This review enriches our understanding of the mosquito immune system and provides evidence to support the development of novel mosquito control strategies.
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Affiliation(s)
- Yan-Hong Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Meng-Meng Chang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xue-Li Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ai-Hua Zheng
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Verlinden H. Dopamine signalling in locusts and other insects. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 97:40-52. [PMID: 29680287 DOI: 10.1016/j.ibmb.2018.04.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/05/2018] [Accepted: 04/08/2018] [Indexed: 06/08/2023]
Abstract
Dopamine is an important catecholamine neurotransmitter in invertebrates and vertebrates. It is biochemically derived from tyrosine via L-DOPA. It is most abundant in the central nervous system, but can also be produced in e.g. epidermal cells. Dopamine has conserved roles in the control of movement, pleasure, motivation, arousal and memory between invertebrate and vertebrate animals. It is crucial for melanisation and sclerotisation, important processes for the formation of the exoskeleton of insects and immune function. In this brief review I will discuss some general aspects of insect dopamine biosynthesis and breakdown, dopamine receptors and their pharmacology. In addition, I will provide a glance on the multitude of biological functions of dopamine in insects. More detail is provided concerning the putative roles of dopamine in phase related phenomena in locusts. Finally, molecular and pharmacological adjustments of insect dopamine signalling are discussed in the light of possible approaches towards insect pest management.
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Affiliation(s)
- Heleen Verlinden
- Department of Animal Physiology and Neurobiology, Zoological Institute, KU Leuven, Naamsestraat 59, 3000 Leuven, Belgium.
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27
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de Carvalho GA, Ramos RAN, TrindadeMaia R, de Andrade CFS, Alves CL. Melanization of Dirofilaria immitis Larvae in Different Culicid Species. J Arthropod Borne Dis 2018; 12:94-99. [PMID: 30018997 PMCID: PMC6046106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/03/2018] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Dirofilaria immitis is an important filarioid transmitted by culicids. The vector role of these arthropods may be influenced by biological events as melanization against D. immitis larvae. This study aimed to detect the occurrence of melanization in Culex quinquefasciatus, Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus experimentally infected with D. immitis. METHODS Five populations (Cx. quinquefasciatus RECIFE (P1), Ae. albopictus RECIFE (P2), Ae. aegypti RECIFE (P3), Ae. aegypti CAMPINAS (P4) and Ae. aegypti ROCKEFELLER (P5)) were artificially fed with infected blood containing D. immitis microfilariae. Ten mosquitoes per day from each population were dissected for 14 days. RESULTS Melanized larvae of D. immitis were observed in all population except in P3. The period in which melanized larvae were found varied from the third to the 14th day post-infection. Difference in the number of these larvae was observed between P5 and P2-P3 (P< 0.01), and between P5 and P4 (P< 0.05). Third-stage larvae of D. immitis were detected in all population 14 d post-infection, except in P3, which presented high mortality 24 h post-infection. The melanization observed in the populations herein studied did not indicate refractory since third-stage larvae were observed at the end of the experiment. Most likely, this immune response aimed to control the number of larvae, in order to maintain the equilibrium between vector-parasite. CONCLUSION The melanization did not seem to be a limiting factor to the development of this filarioid in these local Brazilian Culicidae populations.
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Affiliation(s)
- Gandílcia Aparecida de Carvalho
- Academic Unit of Garanhuns, Federal Rural University of Pernambuco, Garanhuns, Brazil,Corresponding author: Prof Gílcia A. Carvalho, E-mail:
| | | | - Rafael TrindadeMaia
- Department of Biological Sciences, Federal University of Campina Grande, Sumé, Brazil
| | | | - Candâmara Leucio Alves
- Department of Veterinary Medicine, Federal Rural University of Pernambuco, Recife, Brazil
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