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Urakova N, Joseph RE, Huntsinger A, Macias VM, Jones MJ, Sigle LT, Li M, Akbari OS, Xi Z, Lymperopoulos K, Sayre RT, McGraw EA, Rasgon JL. Alpha-mannosidase-2 modulates arbovirus infection in a pathogen- and Wolbachia-specific manner in Aedes aegypti mosquitoes. INSECT MOLECULAR BIOLOGY 2024; 33:362-371. [PMID: 38450861 PMCID: PMC11233229 DOI: 10.1111/imb.12904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 02/22/2024] [Indexed: 03/08/2024]
Abstract
Multiple Wolbachia strains can block pathogen infection, replication and/or transmission in Aedes aegypti mosquitoes under both laboratory and field conditions. However, Wolbachia effects on pathogens can be highly variable across systems and the factors governing this variability are not well understood. It is increasingly clear that the mosquito host is not a passive player in which Wolbachia governs pathogen transmission phenotypes; rather, the genetics of the host can significantly modulate Wolbachia-mediated pathogen blocking. Specifically, previous work linked variation in Wolbachia pathogen blocking to polymorphisms in the mosquito alpha-mannosidase-2 (αMan2) gene. Here we use CRISPR-Cas9 mutagenesis to functionally test this association. We developed αMan2 knockouts and examined effects on both Wolbachia and virus levels, using dengue virus (DENV; Flaviviridae) and Mayaro virus (MAYV; Togaviridae). Wolbachia titres were significantly elevated in αMan2 knockout (KO) mosquitoes, but there were complex interactions with virus infection and replication. In Wolbachia-uninfected mosquitoes, the αMan2 KO mutation was associated with decreased DENV titres, but in a Wolbachia-infected background, the αMan2 KO mutation significantly increased virus titres. In contrast, the αMan2 KO mutation significantly increased MAYV replication in Wolbachia-uninfected mosquitoes and did not affect Wolbachia-mediated virus blocking. These results demonstrate that αMan2 modulates arbovirus infection in A. aegypti mosquitoes in a pathogen- and Wolbachia-specific manner, and that Wolbachia-mediated pathogen blocking is a complex phenotype dependent on the mosquito host genotype and the pathogen. These results have a significant impact for the design and use of Wolbachia-based strategies to control vector-borne pathogens.
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Affiliation(s)
- Nadya Urakova
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Renuka E Joseph
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Allyn Huntsinger
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Vanessa M Macias
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Matthew J Jones
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Leah T Sigle
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Ming Li
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, USA
| | - Omar S Akbari
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, USA
| | - Zhiyong Xi
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | | | - Richard T Sayre
- Pebble Labs, Little Fly Division, Los Alamos, New Mexico, USA
| | - Elizabeth A McGraw
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Jason L Rasgon
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, USA
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2
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Vandana V, Dong S, Sheth T, Sun Q, Wen H, Maldonado A, Xi Z, Dimopoulos G. Wolbachia infection-responsive immune genes suppress Plasmodium falciparum infection in Anopheles stephensi. PLoS Pathog 2024; 20:e1012145. [PMID: 38598552 PMCID: PMC11034644 DOI: 10.1371/journal.ppat.1012145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 04/22/2024] [Accepted: 03/22/2024] [Indexed: 04/12/2024] Open
Abstract
Wolbachia, a maternally transmitted symbiotic bacterium of insects, can suppress a variety of human pathogens in mosquitoes, including malaria-causing Plasmodium in the Anopheles vector. However, the mechanistic basis of Wolbachia-mediated Plasmodium suppression in mosquitoes is not well understood. In this study, we compared the midgut and carcass transcriptomes of stably infected Anopheles stephensi with Wolbachia wAlbB to uninfected mosquitoes in order to discover Wolbachia infection-responsive immune genes that may play a role in Wolbachia-mediated anti-Plasmodium activity. We show that wAlbB infection upregulates 10 putative immune genes and downregulates 14 in midguts, while it upregulates 31 putative immune genes and downregulates 15 in carcasses at 24 h after blood-fed feeding, the time at which the Plasmodium ookinetes are traversing the midgut tissue. Only a few of these regulated immune genes were also significantly differentially expressed between Wolbachia-infected and non-infected midguts and carcasses of sugar-fed mosquitoes. Silencing of the Wolbachia infection-responsive immune genes TEP 4, TEP 15, lysozyme C2, CLIPB2, CLIPB4, PGRP-LD and two novel genes (a peritrophin-44-like gene and a macro domain-encoding gene) resulted in a significantly greater permissiveness to P. falciparum infection. These results indicate that Wolbachia infection modulates mosquito immunity and other processes that are likely to decrease Anopheles permissiveness to Plasmodium infection.
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Affiliation(s)
- Vandana Vandana
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Shengzhang Dong
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Tanaya Sheth
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Qiang Sun
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - Han Wen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - Amanda Maldonado
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Zhiyong Xi
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - George Dimopoulos
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
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3
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Alton LA, Novelo M, Beaman JE, Arnold PA, Bywater CL, Kerton EJ, Lombardi EJ, Koh C, McGraw EA. Exposure to ultraviolet-B radiation increases the susceptibility of mosquitoes to infection with dengue virus. GLOBAL CHANGE BIOLOGY 2023; 29:5540-5551. [PMID: 37560790 DOI: 10.1111/gcb.16906] [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: 11/10/2022] [Revised: 06/11/2023] [Accepted: 07/15/2023] [Indexed: 08/11/2023]
Abstract
By 2100, greenhouse gases are predicted to reduce ozone and cloud cover over the tropics causing increased exposure of organisms to harmful ultraviolet-B radiation (UVBR). UVBR damages DNA and is an important modulator of immune function and disease susceptibility in humans and other vertebrates. The effect of UVBR on invertebrate immune function is largely unknown, but UVBR together with ultraviolet-A radiation impairs an insect immune response that utilizes melanin, a pigment that also protects against UVBR-induced DNA damage. If UVBR weakens insect immunity, then it may make insect disease vectors more susceptible to infection with pathogens of socioeconomic and public health importance. In the tropics, where UVBR is predicted to increase, the mosquito-borne dengue virus (DENV), is prevalent and a growing threat to humans. We therefore examined the effect of UVBR on the mosquito Aedes aegypti, the primary vector for DENV, to better understand the potential implications of increased tropical UVBR for mosquito-borne disease risk. We found that exposure to a UVBR dose that caused significant larval mortality approximately doubled the probability that surviving females would become infected with DENV, despite this UVBR dose having no effect on the expression of an effector gene involved in antiviral immunity. We also found that females exposed to a lower UVBR dose were more likely to have low fecundity even though this UVBR dose had no effect on larval size or activity, pupal cuticular melanin content, or adult mass, metabolic rate, or flight capacity. We conclude that future increases in tropical UVBR associated with anthropogenic global change may have the benefit of reducing mosquito-borne disease risk for humans by reducing mosquito fitness, but this benefit may be eroded if it also makes mosquitoes more likely to be infected with deadly pathogens.
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Affiliation(s)
- Lesley A Alton
- Centre for Geometric Biology, Monash University, Melbourne, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Mario Novelo
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
- Department of Entomology, Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Julian E Beaman
- Centre for Geometric Biology, Monash University, Melbourne, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Pieter A Arnold
- Centre for Geometric Biology, Monash University, Melbourne, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Candice L Bywater
- Centre for Geometric Biology, Monash University, Melbourne, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Emily J Kerton
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Emily J Lombardi
- Centre for Geometric Biology, Monash University, Melbourne, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Cassandra Koh
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Elizabeth A McGraw
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
- Department of Biology, Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, USA
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4
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Lau MJ, Dutra HLC, Jones MJ, McNulty BP, Diaz AM, Ware-Gilmore F, McGraw EA. Jamestown Canyon virus is transmissible by Aedes aegypti and is only moderately blocked by Wolbachia co-infection. PLoS Negl Trop Dis 2023; 17:e0011616. [PMID: 37669272 PMCID: PMC10503764 DOI: 10.1371/journal.pntd.0011616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/15/2023] [Accepted: 08/22/2023] [Indexed: 09/07/2023] Open
Abstract
Jamestown Canyon virus (JCV), a negative-sense arbovirus, is increasingly common in the upper Midwest of the USA. Transmitted by a range of mosquito genera, JCV's primary amplifying host is white-tailed deer. Aedes aegypti is responsible for transmitting various positive-sense viruses globally including dengue (DENV), Zika, chikungunya, and Yellow Fever. Ae. aegypti's distribution, once confined to the tropics, is expanding, in part due to climate change. Wolbachia, an insect endosymbiont, limits the replication of co-infecting viruses inside insects. The release and spread of the symbiont into Ae. aegypti populations have been effective in reducing transmission of DENV to humans, although the mechanism of Wolbachia-mediated viral blocking is still poorly understood. Here we explored JCV infection potential in Ae. aegypti, the nature of the vector's immune response, and interactions with Wolbachia infection. We show that Ae. aegypti is highly competent for JCV, which grows to high loads and rapidly reaches the saliva after an infectious blood meal. The mosquito immune system responds with strong induction of RNAi and JAK/STAT. Neither the direct effect of viral infection nor the energetic investment in immunity appears to affect mosquito longevity. Wolbachia infection blocked JCV only in the early stages of infection. Wolbachia-induced immunity was small compared to that of JCV, suggesting innate immune priming does not likely explain blocking. We propose two models to explain why Wolbachia's blocking of negative-sense viruses like JCV may be less than that of positive-sense viruses, relating to the slowdown of host protein synthesis and the triggering of interferon-like factors like Vago. In conclusion, we highlight the risk for increased human disease with the predicted future overlap of Ae. aegypti and JCV ranges. We suggest that with moderate Wolbachia-mediated blocking and distinct biology, negative-sense viruses represent a fruitful comparator model to other viruses for understanding blocking mechanisms in mosquitoes.
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Affiliation(s)
- Meng-Jia Lau
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Heverton L. C. Dutra
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Matthew J. Jones
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Brianna P. McNulty
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Anastacia M. Diaz
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Fhallon Ware-Gilmore
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Elizabeth A. McGraw
- Biology Department, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
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5
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Ant TH, Mancini MV, McNamara CJ, Rainey SM, Sinkins SP. Wolbachia-Virus interactions and arbovirus control through population replacement in mosquitoes. Pathog Glob Health 2023; 117:245-258. [PMID: 36205550 PMCID: PMC10081064 DOI: 10.1080/20477724.2022.2117939] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2022] Open
Abstract
Following transfer into the primary arbovirus vector Aedes aegypti, several strains of the intracellular bacterium Wolbachia have been shown to inhibit the transmission of dengue, Zika, and chikungunya viruses, important human pathogens that cause significant morbidity and mortality worldwide. In addition to pathogen inhibition, many Wolbachia strains manipulate host reproduction, resulting in an invasive capacity of the bacterium in insect populations. This has led to the deployment of Wolbachia as a dengue control tool, and trials have reported significant reductions in transmission in release areas. Here, we discuss the possible mechanisms of Wolbachia-virus inhibition and the implications for long-term success of dengue control. We also consider the evidence presented in several reports that Wolbachia may cause an enhancement of replication of certain viruses under particular conditions, and conclude that these should not cause any concerns with respect to the application of Wolbachia to arbovirus control.
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Affiliation(s)
- Thomas H Ant
- Centre for Virus Research, University of Glasgow, Glasgow, UK
| | - Maria Vittoria Mancini
- Centre for Virus Research, University of Glasgow, Glasgow, UK
- Polo d’Innovazione di Genomica, Genetica e Biologia, Terni, Italy
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6
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Novelo M, Dutra HLC, Metz HC, Jones MJ, Sigle LT, Frentiu FD, Allen SL, Chenoweth SF, McGraw EA. Dengue and chikungunya virus loads in the mosquito Aedes aegypti are determined by distinct genetic architectures. PLoS Pathog 2023; 19:e1011307. [PMID: 37043515 PMCID: PMC10124881 DOI: 10.1371/journal.ppat.1011307] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 04/24/2023] [Accepted: 03/19/2023] [Indexed: 04/13/2023] Open
Abstract
Aedes aegypti is the primary vector of the arboviruses dengue (DENV) and chikungunya (CHIKV). These viruses exhibit key differences in their vector interactions, the latter moving more quicky through the mosquito and triggering fewer standard antiviral pathways. As the global footprint of CHIKV continues to expand, we seek to better understand the mosquito's natural response to CHIKV-both to compare it to DENV:vector coevolutionary history and to identify potential targets in the mosquito for genetic modification. We used a modified full-sibling design to estimate the contribution of mosquito genetic variation to viral loads of both DENV and CHIKV. Heritabilities were significant, but higher for DENV (40%) than CHIKV (18%). Interestingly, there was no genetic correlation between DENV and CHIKV loads between siblings. These data suggest Ae. aegypti mosquitoes respond to the two viruses using distinct genetic mechanisms. We also examined genome-wide patterns of gene expression between High and Low CHIKV families representing the phenotypic extremes of viral load. Using RNAseq, we identified only two loci that consistently differentiated High and Low families: a long non-coding RNA that has been identified in mosquito screens post-infection and a distant member of a family of Salivary Gland Specific (SGS) genes. Interestingly, the latter gene is also associated with horizontal gene transfer between mosquitoes and the endosymbiotic bacterium Wolbachia. This work is the first to link the SGS gene to a mosquito phenotype. Understanding the molecular details of how this gene contributes to viral control in mosquitoes may, therefore, also shed light on its role in Wolbachia.
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Affiliation(s)
- Mario Novelo
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Heverton LC Dutra
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Hillery C. Metz
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Matthew J. Jones
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Leah T. Sigle
- Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Francesca D. Frentiu
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Herston, Queensland, Australia
| | - Scott L. Allen
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
| | - Stephen F. Chenoweth
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
| | - Elizabeth A. McGraw
- Center for Infectious Disease Dynamics, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
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7
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Wimalasiri-Yapa BMCR, Huang B, Ross PA, Hoffmann AA, Ritchie SA, Frentiu FD, Warrilow D, van den Hurk AF. Differences in gene expression in field populations of Wolbachia-infected Aedes aegypti mosquitoes with varying release histories in northern Australia. PLoS Negl Trop Dis 2023; 17:e0011222. [PMID: 36989319 PMCID: PMC10085034 DOI: 10.1371/journal.pntd.0011222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 04/10/2023] [Accepted: 03/07/2023] [Indexed: 03/30/2023] Open
Abstract
Aedes aegypti is the principal mosquito vector of dengue, yellow fever, Zika and chikungunya viruses. The wMel strain of the endosymbiotic bacteria Wolbachia pipientis was introduced into the vector as a novel biocontrol strategy to stop transmission of these viruses. Mosquitoes with Wolbachia have been released in the field in Northern Queensland, Australia since 2011, at various locations and over several years, with populations remaining stably infected. Wolbachia infection is known to alter gene expression in its mosquito host, but whether (and how) this changes over the long-term in the context of field releases remains unknown. We sampled mosquitoes from Wolbachia-infected populations with three different release histories along a time gradient and performed RNA-seq to investigate gene expression changes in the insect host. We observed a significant impact on gene expression in Wolbachia-infected mosquitoes versus uninfected controls. Fewer genes had significantly upregulated expression in mosquitoes from the older releases (512 and 486 from the 2011 and 2013/14 release years, respectively) versus the more recent releases (1154 from the 2017 release year). Nonetheless, a fundamental signature of Wolbachia infection on host gene expression was observed across all releases, comprising upregulation of immunity (e.g. leucine-rich repeats, CLIPs) and metabolism (e.g. lipid metabolism, iron transport) genes. There was limited downregulation of gene expression in mosquitoes from the older releases (84 and 71 genes from the 2011 and 2013/14 release years, respectively), but significantly more in the most recent release (509 from the 2017 release year). Our findings indicate that at > 8 years post-introgression into field populations, Wolbachia continues to profoundly impact expression of host genes, such as those involved in insect immune response and metabolism. If Wolbachia-mediated virus blocking is underpinned by these differential gene expression changes, our results suggest it may remain stable long-term.
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Affiliation(s)
- B M C Randika Wimalasiri-Yapa
- Department of Medical Laboratory Sciences, Faculty of Health Sciences, Open University of Sri Lanka, Nugegoda, Colombo, Sri Lanka
- School of Biomedical Sciences and Centre for Immunology and Infection Control, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Bixing Huang
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, Queensland, Australia
| | - Perran A Ross
- Pest and Environmental Adaptation Research Group, School of BioSciences, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Ary A Hoffmann
- Pest and Environmental Adaptation Research Group, School of BioSciences, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Scott A Ritchie
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - Francesca D Frentiu
- School of Biomedical Sciences and Centre for Immunology and Infection Control, Queensland University of Technology, Brisbane, Queensland, Australia
| | - David Warrilow
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, Queensland, Australia
| | - Andrew F van den Hurk
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Coopers Plains, Queensland, Australia
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8
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Ferreira QR, Lemos FFB, Moura MN, Nascimento JODS, Novaes AF, Barcelos IS, Fernandes LA, Amaral LSDB, Barreto FK, de Melo FF. Role of the Microbiome in Aedes spp. Vector Competence: What Do We Know? Viruses 2023; 15:779. [PMID: 36992487 PMCID: PMC10051417 DOI: 10.3390/v15030779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/03/2023] [Accepted: 03/15/2023] [Indexed: 03/31/2023] Open
Abstract
Aedes aegypti and Aedes albopictus are the vectors of important arboviruses: dengue fever, chikungunya, Zika, and yellow fever. Female mosquitoes acquire arboviruses by feeding on the infected host blood, thus being able to transmit it to their offspring. The intrinsic ability of a vector to infect itself and transmit a pathogen is known as vector competence. Several factors influence the susceptibility of these females to be infected by these arboviruses, such as the activation of the innate immune system through the Toll, immunodeficiency (Imd), JAK-STAT pathways, and the interference of specific antiviral response pathways of RNAi. It is also believed that the presence of non-pathogenic microorganisms in the microbiota of these arthropods could influence this immune response, as it provides a baseline activation of the innate immune system, which may generate resistance against arboviruses. In addition, this microbiome has direct action against arboviruses, mainly due to the ability of Wolbachia spp. to block viral genome replication, added to the competition for resources within the mosquito organism. Despite major advances in the area, studies are still needed to evaluate the microbiota profiles of Aedes spp. and their vector competence, as well as further exploration of the individual roles of microbiome components in activating the innate immune system.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Fernanda Khouri Barreto
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
| | - Fabrício Freire de Melo
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
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9
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Hussain M, Etebari K, Asgari S. Analysing inhibition of dengue virus in Wolbachia-infected mosquito cells following the removal of Wolbachia. Virology 2023; 581:48-55. [PMID: 36889142 DOI: 10.1016/j.virol.2023.02.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023]
Abstract
Wolbachia pipientis is known to block replication of positive sense RNA viruses. Previously, we created an Aedes aegypti Aag2 cell line (Aag2.wAlbB) transinfected with the wAlbB strain of Wolbachia and a matching tetracycline-cured Aag2.tet cell line. While dengue virus (DENV) was blocked in Aag2.wAlbB cells, we found significant inhibition of DENV in Aag2.tet cells. RNA-Seq analysis of the cells confirmed removal of Wolbachia and lack of expression of Wolbachia genes that could have been due to lateral gene transfer in Aag2.tet cells. However, we noticed a substantial increase in the abundance of phasi charoen-like virus (PCLV) in Aag2.tet cells. When RNAi was used to reduce the PCLV levels, DENV replication was significantly increased. Further, we found significant changes in the expression of antiviral and proviral genes in Aag2.tet cells. Overall, the results reveal an antagonistic interaction between DENV and PCLV and how PCLV-induced changes could contribute to DENV inhibition.
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Affiliation(s)
- Mazhar Hussain
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Kayvan Etebari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Sassan Asgari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
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10
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Hussain M, Zhang G, Leitner M, Hedges LM, Asgari S. Wolbachia RNase HI contributes to virus blocking in the mosquito Aedes aegypti. iScience 2022; 26:105836. [PMID: 36636344 PMCID: PMC9830209 DOI: 10.1016/j.isci.2022.105836] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/14/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
The endosymbiotic bacterium Wolbachia pipientis blocks replication of several arboviruses in transinfected Aedes aegypti mosquitoes. However, the mechanism of virus blocking remains poorly understood. Here, we characterized an RNase HI gene from Wolbachia, which is rapidly induced in response to dengue virus (DENV) infection. Knocking down w RNase HI using antisense RNA in Wolbachia-transinfected mosquito cell lines and A. aegypti mosquitoes led to increased DENV replication. Furthermore, overexpression of wRNase HI, in the absence of Wolbachia, led to reduced replication of a positive sense RNA virus, but had no effect on a negative sense RNA virus, a familiar scenario in Wolbachia-infected cells. Altogether, our results provide compelling evidence for the missing link between early Wolbachia-mediated virus blocking and degradation of viral RNA. These findings and the successful pioneered knockdown of Wolbachia genes using antisense RNA in cell line and mosquitoes enable new ways to manipulate and study the complex endosymbiont-host interactions.
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Affiliation(s)
- Mazhar Hussain
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Guangmei Zhang
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Michael Leitner
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Lauren M. Hedges
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Sassan Asgari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia,Corresponding author
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Bishop C, Hussain M, Hugo LE, Asgari S. Analysis of Aedes aegypti microRNAs in response to Wolbachia wAlbB infection and their potential role in mosquito longevity. Sci Rep 2022; 12:15245. [PMID: 36085160 PMCID: PMC9463151 DOI: 10.1038/s41598-022-19574-x] [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: 05/13/2022] [Accepted: 08/31/2022] [Indexed: 11/09/2022] Open
Abstract
The mosquito Aedes aegypti is the primary vector of a range of medically important viruses including dengue, Zika, West Nile, yellow fever, and chikungunya viruses. The endosymbiotic bacterium Wolbachia pipientis wAlbB strain is a promising biocontrol agent for blocking viral transmission by Ae. aegypti. To predict the long-term efficacy of field applications, a thorough understanding of the interactions between symbiont, host, and pathogen is required. Wolbachia influences host physiology in a variety of ways including reproduction, immunity, metabolism, and longevity. MicroRNAs (miRNAs) are highly conserved small non-coding RNAs that regulate gene expression in eukaryotes and viruses. Several miRNAs are known to regulate biological processes in Drosophila and mosquitoes, including facilitating Wolbachia maintenance. We generated the first chromosomal map of Ae. aegypti miRNAs, and compared miRNA expression profiles between a wAlbB-transinfected Ae. aegypti mosquito line and a tetracycline cleared derivative, using deep small RNA-sequencing. We found limited modulation of miRNAs in response to wAlbB infection. Several miRNAs were modulated in response to age, some of which showed greater upregulation in wAlbB-infected mosquitoes than in tetracycline cleared ones. By selectively inhibiting some differentially expressed miRNAs, we identified miR-2946-3p and miR-317-3p as effecting mosquito longevity in Wolbachia-infected mosquitoes.
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Affiliation(s)
- Cameron Bishop
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Mazhar Hussain
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Leon E Hugo
- Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, 300 Herston Road, Herston, 4006, Australia
| | - Sassan Asgari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
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12
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Boonyakida J, Nakanishi T, Satoh J, Shimahara Y, Mekata T, Park EY. Immunostimulation of shrimp through oral administration of silkworm pupae expressing VP15 against WSSV. FISH & SHELLFISH IMMUNOLOGY 2022; 128:157-167. [PMID: 35917887 DOI: 10.1016/j.fsi.2022.07.043] [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: 03/14/2022] [Revised: 07/15/2022] [Accepted: 07/16/2022] [Indexed: 06/15/2023]
Abstract
White spot syndrome virus (WSSV) is one of the most concerning pathogens in penaeid shrimp and can cause severe loss in shrimp aquaculture worldwide. Among the WSSV structural proteins, VP15, a DNA-binding protein located in the WSSV nucleocapsid, is an antiviral protein candidate to protect kuruma shrimp (Marsupenaeus japonicus) from WSSV infection. We identified that the truncated VP15, VP15(26-57), is responsible for the protective effect against the WSSV. This study attempts to develop an immunizing agent against WSSV using silkworm pupa as a delivery vector through oral administration. The VP15, VP15(26-57), and SR11 peptide derived from VP15(26-57) were expressed in silkworm pupae. Oral administration of feed mixed with the powdered pupae that expressed VP15-derived constructs enhanced the survivability of kuruma shrimp with an overall relative percent survival (RPS) higher than 70%. There is no death for the group receiving pupa/VP15(26-57), and the RPS is 100%. In addition, we also investigated the relative mRNA expression levels of immune-related genes by qPCR at different time points. Our results indicate that the oral administration of pupa/VP15-derived products could provide a high protective effect against WSSV and be a practical approach for controlling WSSV in aquaculture.
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Affiliation(s)
- Jirayu Boonyakida
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ward, Shizuoka, 422-8529, Japan.
| | - Takafumi Nakanishi
- Department of Applied Biological Chemistry, Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ward, Shizuoka, 422-8529, Japan.
| | - Jun Satoh
- Fisheries Technology Institute of National Research and Development Agency, Japan Fisheries Research and Education Agency, Tamaki Field Station, Mie, 519-0423, Japan.
| | - Yoshiko Shimahara
- Fisheries Technology Institute of National Research and Development Agency, Japan Fisheries Research and Education Agency, Kamiura Field Station, Oita, 879-2602, Japan.
| | - Tohru Mekata
- Fisheries Technology Institute of National Research and Development Agency, Japan Fisheries Research and Education Agency, Namsei Field Station, Mie, 516-0193, Japan.
| | - Enoch Y Park
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ward, Shizuoka, 422-8529, Japan; Department of Applied Biological Chemistry, Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ward, Shizuoka, 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ward, Shizuoka, 422-8529, Japan.
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Gómez M, Martinez D, Muñoz M, Ramírez JD. Aedes aegypti and Ae. albopictus microbiome/virome: new strategies for controlling arboviral transmission? Parasit Vectors 2022; 15:287. [PMID: 35945559 PMCID: PMC9364528 DOI: 10.1186/s13071-022-05401-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 07/14/2022] [Indexed: 02/07/2023] Open
Abstract
Aedes aegypti and Aedes albopictus are the main vectors of highly pathogenic viruses for humans, such as dengue (DENV), chikungunya (CHIKV), and Zika (ZIKV), which cause febrile, hemorrhagic, and neurological diseases and remain a major threat to global public health. The high ecological plasticity, opportunistic feeding patterns, and versatility in the use of urban and natural breeding sites of these vectors have favored their dispersal and adaptation in tropical, subtropical, and even temperate zones. Due to the lack of available treatments and vaccines, mosquito population control is the most effective way to prevent arboviral diseases. Resident microorganisms play a crucial role in host fitness by preventing or enhancing its vectorial ability to transmit viral pathogens. High-throughput sequencing and metagenomic analyses have advanced our understanding of the composition and functionality of the microbiota of Aedes spp. Interestingly, shotgun metagenomics studies have established that mosquito vectors harbor a highly conserved virome composed of insect-specific viruses (ISV). Although ISVs are not infectious to vertebrates, they can alter different phases of the arboviral cycle, interfering with transmission to the human host. Therefore, this review focuses on the description of Ae. aegypti and Ae. albopictus as vectors susceptible to infection by viral pathogens, highlighting the role of the microbiota-virome in vectorial competence and its potential in control strategies for new emerging and re-emerging arboviruses.
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Affiliation(s)
- Marcela Gómez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia.,Grupo de Investigación en Ciencias Básicas (NÚCLEO) Facultad de Ciencias e Ingeniería, Universidad de Boyacá, Tunja, Colombia
| | - David Martinez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Marina Muñoz
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Juan David Ramírez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia. .,Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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14
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Sigle LT, Jones M, Novelo M, Ford SA, Urakova N, Lymperopoulos K, Sayre RT, Xi Z, Rasgon JL, McGraw EA. Assessing Aedes aegypti candidate genes during viral infection and Wolbachia-mediated pathogen blocking. INSECT MOLECULAR BIOLOGY 2022; 31:356-368. [PMID: 35112745 PMCID: PMC9081237 DOI: 10.1111/imb.12764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 01/11/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
One approach to control dengue virus transmission is the symbiont Wolbachia, which limits viral infection in mosquitoes. Despite plans for its widespread use in Aedes aegypti, Wolbachia's mode of action remains poorly understood. Many studies suggest that the mechanism is likely multifaceted, involving aspects of immunity, cellular stress and nutritional competition. A previous study from our group used artificial selection to identify a new mosquito candidate gene related to viral blocking; alpha-mannosidase-2a (alpha-Mann-2a) with a predicted role in protein glycosylation. Protein glycosylation pathways tend to be involved in complex host-viral interactions; however, the function of alpha-mannosidases has not been described in mosquito-virus interactions. We examined alpha-Mann-2a expression in response to virus and Wolbachia infections and whether reduced gene expression, caused by RNA interference, affected viral loads. We show that dengue virus (DENV) infection affects the expression of alpha-Mann-2a in a tissue- and time-dependent manner, whereas Wolbachia infection had no effect. In the midgut, DENV prevalence increased following knockdown of alpha-Mann-2a expression in Wolbachia-free mosquitoes, suggesting that alpha-Mann-2a interferes with infection. Expression knockdown had the same effect on the togavirus chikungunya virus, indicating that alpha-Mann-2a may have broad antivirus effects in the midgut. Interestingly, we were unable to knockdown the expression in Wolbachia-infected mosquitoes. We also provide evidence that alpha-Mann-2a may affect the transcriptional level of another gene predicted to be involved in viral blocking and cell adhesion; cadherin87a. These data support the hypothesis that glycosylation and adhesion pathways may broadly be involved in viral infection in Ae. aegypti.
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Affiliation(s)
- Leah T. Sigle
- Department of Entomology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Matthew Jones
- Department of Entomology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Mario Novelo
- Department of Entomology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Suzanne A. Ford
- Department of Entomology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Nadya Urakova
- Department of Entomology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | | | | | - Zhiyong Xi
- Department of Microbiology and Molecular GeneticsMichigan State UniversityEast LansingMichiganUSA
| | - Jason L. Rasgon
- Department of Entomology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Elizabeth A. McGraw
- Department of Biology and Center for Infectious Disease DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
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15
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Trammell CE, Ramirez G, Sanchez-Vargas I, St Clair LA, Ratnayake OC, Luckhart S, Perera R, Goodman AG. Coupled small molecules target RNA interference and JAK/STAT signaling to reduce Zika virus infection in Aedes aegypti. PLoS Pathog 2022; 18:e1010411. [PMID: 35377915 PMCID: PMC9017935 DOI: 10.1371/journal.ppat.1010411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 04/19/2022] [Accepted: 03/01/2022] [Indexed: 01/16/2023] Open
Abstract
The recent global Zika epidemics have revealed the significant threat that mosquito-borne viruses pose. There are currently no effective vaccines or prophylactics to prevent Zika virus (ZIKV) infection. Limiting exposure to infected mosquitoes is the best way to reduce disease incidence. Recent studies have focused on targeting mosquito reproduction and immune responses to reduce transmission. Previous work has evaluated the effect of insulin signaling on antiviral JAK/STAT and RNAi in vector mosquitoes. Specifically, insulin-fed mosquitoes resulted in reduced virus replication in an RNAi-independent, ERK-mediated JAK/STAT-dependent mechanism. In this work, we demonstrate that targeting insulin signaling through the repurposing of small molecule drugs results in the activation of both RNAi and JAK/STAT antiviral pathways. ZIKV-infected Aedes aegypti were fed blood containing demethylasterriquinone B1 (DMAQ-B1), a potent insulin mimetic, in combination with AKT inhibitor VIII. Activation of this coordinated response additively reduced ZIKV levels in Aedes aegypti. This effect included a quantitatively greater reduction in salivary gland ZIKV levels up to 11 d post-bloodmeal ingestion, relative to single pathway activation. Together, our study indicates the potential for field delivery of these small molecules to substantially reduce virus transmission from mosquito to human. As infections like Zika virus are becoming more burdensome and prevalent, understanding how to control this family of viruses in the insect vector is an important issue in public health.
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Affiliation(s)
- Chasity E. Trammell
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Gabriela Ramirez
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Irma Sanchez-Vargas
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Laura A. St Clair
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Oshani C. Ratnayake
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Shirley Luckhart
- Department of Entomology, Plant Pathology, and Nematology, College of Agricultural and Life Sciences, University of Idaho, Moscow, Idaho, United States of America
- Department of Biological Sciences, College of Science, University of Idaho, Moscow, Idaho, United States of America
| | - Rushika Perera
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
- * E-mail: (RP); (AGG)
| | - Alan G. Goodman
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- Paul G. Allen School for Global Health, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- * E-mail: (RP); (AGG)
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16
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Japanese Encephalitis Virus Interaction with Mosquitoes: A Review of Vector Competence, Vector Capacity and Mosquito Immunity. Pathogens 2022; 11:pathogens11030317. [PMID: 35335641 PMCID: PMC8953304 DOI: 10.3390/pathogens11030317] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 02/28/2022] [Accepted: 03/01/2022] [Indexed: 02/01/2023] Open
Abstract
Japanese encephalitis virus (JEV) is a mosquito-borne zoonotic flavivirus and a major cause of human viral encephalitis in Asia. We provide an overview of the knowledge on vector competence, vector capacity, and immunity of mosquitoes in relation to JEV. JEV has so far been detected in more than 30 mosquito species. This does not necessarily mean that these species contribute to JEV transmission under field conditions. Therefore, vector capacity, which considers vector competence, as well as environmental, behavioral, cellular, and biochemical variables, needs to be taken into account. Currently, 17 species can be considered as confirmed vectors for JEV and 10 other species as potential vectors. Culex tritaeniorhynchus and Culex annulirostris are considered primary JEV vectors in endemic regions. Culex pipiens and Aedes japonicus could be considered as potentially important vectors in the case of JEV introduction in new regions. Vector competence is determined by various factors, including vector immunity. The available knowledge on physical and physiological barriers, molecular pathways, antimicrobial peptides, and microbiome is discussed in detail. This review highlights that much remains to be studied about vector immunity against JEV in order to identify novel strategies to reduce JEV transmission by mosquitoes.
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17
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Viglietta M, Bellone R, Blisnick AA, Failloux AB. Vector Specificity of Arbovirus Transmission. Front Microbiol 2021; 12:773211. [PMID: 34956136 PMCID: PMC8696169 DOI: 10.3389/fmicb.2021.773211] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/19/2021] [Indexed: 12/20/2022] Open
Abstract
More than 25% of human infectious diseases are vector-borne diseases (VBDs). These diseases, caused by pathogens shared between animals and humans, are a growing threat to global health with more than 2.5 million annual deaths. Mosquitoes and ticks are the main vectors of arboviruses including flaviviruses, which greatly affect humans. However, all tick or mosquito species are not able to transmit all viruses, suggesting important molecular mechanisms regulating viral infection, dissemination, and transmission by vectors. Despite the large distribution of arthropods (mosquitoes and ticks) and arboviruses, only a few pairings of arthropods (family, genus, and population) and viruses (family, genus, and genotype) successfully transmit. Here, we review the factors that might limit pathogen transmission: internal (vector genetics, immune responses, microbiome including insect-specific viruses, and coinfections) and external, either biotic (adult and larvae nutrition) or abiotic (temperature, chemicals, and altitude). This review will demonstrate the dynamic nature and complexity of virus–vector interactions to help in designing appropriate practices in surveillance and prevention to reduce VBD threats.
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Affiliation(s)
- Marine Viglietta
- Unit of Arboviruses and Insect Vectors, Institut Pasteur, Sorbonne Université, Paris, France
| | - Rachel Bellone
- Unit of Arboviruses and Insect Vectors, Institut Pasteur, Sorbonne Université, Paris, France
| | - Adrien Albert Blisnick
- Unit of Arboviruses and Insect Vectors, Institut Pasteur, Sorbonne Université, Paris, France
| | - Anna-Bella Failloux
- Unit of Arboviruses and Insect Vectors, Institut Pasteur, Sorbonne Université, Paris, France
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Telleria EL, Azevedo-Brito DA, Kykalová B, Tinoco-Nunes B, Pitaluga AN, Volf P, Traub-Csekö YM. Leishmania infantum Infection Modulates the Jak-STAT Pathway in Lutzomyia longipalpis LL5 Embryonic Cells and Adult Females, and Affects Parasite Growth in the Sand Fly. FRONTIERS IN TROPICAL DISEASES 2021. [DOI: 10.3389/fitd.2021.747820] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Phlebotomine sand flies (Diptera, Psychodidae) belonging to the Lutzomyia genus transmit zoonoses in the New World. Lutzomyia longipalpis is the main vector of Leishmania infantum, which is the causative agent of visceral leishmaniasis in Brazil. To identify key molecular aspects involved in the interaction between vector and pathogens and contribute to developing disease transmission controls, we investigated the sand fly innate immunity mediated by the Janus kinase/signal transducer and activator of transcription (Jak-STAT) pathway in response to L. infantum infection. We used two study models: L. longipalpis LL5 embryonic cells co-cultured with L. infantum and sand fly females artificially infected with the parasite. We used qPCR to follow the L. longipalpis gene expression of molecules involved in the Jak-STAT pathway. Also, we modulated the Jak-STAT mediated immune response to understand its role in Leishmania parasite infection. For that, we used RNAi to silence the pathway regulators, protein inhibitor of activated STATs (PIAS) in LL5 cells, and STAT in adult females. In addition, the pathway suppression effect on parasite development within the vector was assessed by light microscopy in late-phase infection. The silencing of the repressor PIAS in LL5 cells led to a moderate increase in a protein tyrosine phosphatase 61F (PTP61F) expression. It suggests a compensatory regulation between these two repressors. L. infantum co-culture with LL5 cells upregulated repressors PIAS, suppressor of cytokine signaling (SOCS), and PTP61F. It also downmodulated virus-induced RNA-1 (VIR-1), a pathway effector, indicating that the parasite could repress the Jak-STAT pathway in LL5 cells. In Leishmania-infected L. longipalpis females, STAT and the antimicrobial peptide attacin were downregulated on the third day post-infection, suggesting a correlation that favors the parasite survival at the end of blood digestion in the sand fly. The antibiotic treatment of infected females showed that the reduction of gut bacteria had little effect on the Jak-STAT pathway regulation. STAT gene silencing mediated by RNAi reduced the expression of inducible nitric oxide synthase (iNOS) and favored Leishmania growth in sand flies on the first day post-infection. These results indicate that STAT participated in the iNOS regulation with subsequent effect on parasite survival.
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Ortiz-Baez AS, Shi M, Hoffmann AA, Holmes EC. RNA virome diversity and Wolbachia infection in individual Drosophila simulans flies. J Gen Virol 2021; 102. [PMID: 34704919 PMCID: PMC8604192 DOI: 10.1099/jgv.0.001639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The endosymbiont bacteria of the genus Wolbachia are associated with multiple mutualistic effects on insect biology, including nutritional and antiviral properties. Members of the genus Wolbachia naturally occur in fly species of the genus Drosophila, providing an operational model host for studying how virome composition may be affected by its presence. Drosophila simulans populations can carry a variety of strains of members of the genus Wolbachia, with the wAu strain associated with strong antiviral protection under experimental conditions. We used D. simulans sampled from the Perth Hills, Western Australia, to investigate the potential virus protective effect of the wAu strain of Wolbachia on individual wild-caught flies. Our data revealed no appreciable variation in virus composition and abundance between individuals infected or uninfected with Wolbachia associated with the presence or absence of wAu. However, it remains unclear whether wAu might affect viral infection and host survival by increasing tolerance rather than inducing complete resistance. These data also provide new insights into the natural virome diversity of D. simulans. Despite the small number of individuals sampled, we identified a repertoire of RNA viruses, including nora virus, galbut virus, thika virus and La Jolla virus, that have been identified in other species of the genus Drosophila. Chaq virus-like sequences associated with galbut virus were also detected. In addition, we identified five novel viruses from the families Reoviridae, Tombusviridae, Mitoviridae and Bunyaviridae. Overall, this study highlights the complex interaction between Wolbachia and RNA virus infections and provides a baseline description of the natural virome of D. simulans.
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Affiliation(s)
- Ayda Susana Ortiz-Baez
- Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Life and Environmental Sciences and School of Medical Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Mang Shi
- Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Life and Environmental Sciences and School of Medical Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Ary A Hoffmann
- School of BioSciences, Bio21 Institute, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Edward C Holmes
- Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Life and Environmental Sciences and School of Medical Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
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20
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Growth and Maintenance of Wolbachia in Insect Cell Lines. INSECTS 2021; 12:insects12080706. [PMID: 34442272 PMCID: PMC8396524 DOI: 10.3390/insects12080706] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 12/02/2022]
Abstract
Simple Summary Wolbachia is an intracellular bacterium that occurs in arthropods and in filarial worms. First described nearly a century ago in the reproductive tissues of Culex pipiens mosquitoes, Wolbachia is now known to occur in roughly 50% of insect species, and has been considered the most abundant intracellular bacterium on earth. In insect hosts, Wolbachia modifies reproduction in ways that facilitate spread of the microbe within the host population, but otherwise is relatively benign. In this “gene drive” capacity, Wolbachia provides a tool for manipulating mosquito populations. In mosquitoes, Wolbachia causes cytoplasmic incompatibility, in which the fusion of egg and sperm nuclei is disrupted, and eggs fail to hatch, depending on the presence/absence of Wolbachia in the parent insects. Recent findings demonstrate that Wolbachia from infected insects can be transferred into mosquito species that do not host a natural infection. When transinfected into Aedes aegypti, an important vector of dengue and Zika viruses, Wolbachia causes cytoplasmic incompatibility and, in addition, decreases the mosquito’s ability to transmit viruses to humans. This review addresses the maintenance of Wolbachia in insect cell lines, which provide a tool for high-level production of infectious bacteria. In vitro technologies will improve use of Wolbachia for pest control, and provide the microbiological framework for genetic engineering of this promising biocontrol agent. Abstract The obligate intracellular microbe, Wolbachia pipientis (Rickettsiales; Anaplasmataceae), is a Gram-negative member of the alpha proteobacteria that infects arthropods and filarial worms. Although closely related to the genera Anaplasma and Ehrlichia, which include pathogens of humans, Wolbachia is uniquely associated with invertebrate hosts in the clade Ecdysozoa. Originally described in Culex pipiens mosquitoes, Wolbachia is currently represented by 17 supergroups and is believed to occur in half of all insect species. In mosquitoes, Wolbachia acts as a gene drive agent, with the potential to modify vector populations; in filarial worms, Wolbachia functions as a symbiont, and is a target for drug therapy. A small number of Wolbachia strains from supergroups A, B, and F have been maintained in insect cell lines, which are thought to provide a more permissive environment than the natural host. When transferred back to an insect host, Wolbachia produced in cultured cells are infectious and retain reproductive phenotypes. Here, I review applications of insect cell lines in Wolbachia research and describe conditions that facilitate Wolbachia infection and replication in naive host cells. Progress in manipulation of Wolbachia in vitro will enable genetic and biochemical advances that will facilitate eventual genetic engineering of this important biological control agent.
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21
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Caragata EP, Dutra HLC, Sucupira PHF, Ferreira AGA, Moreira LA. Wolbachia as translational science: controlling mosquito-borne pathogens. Trends Parasitol 2021; 37:1050-1067. [PMID: 34303627 DOI: 10.1016/j.pt.2021.06.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/21/2021] [Accepted: 06/29/2021] [Indexed: 01/23/2023]
Abstract
In this review we examine how exploiting the Wolbachia-mosquito relationship has become an increasingly popular strategy for controlling arbovirus transmission. Field deployments of Wolbachia-infected mosquitoes have led to significant decreases in dengue virus incidence via high levels of mosquito population suppression and replacement, emphasizing the success of Wolbachia approaches. Here, we examine how improved knowledge of Wolbachia-host interactions has provided key insight into the mechanisms of the essential phenotypes of pathogen blocking and cytoplasmic incompatibility. And we discuss recent studies demonstrating that extrinsic factors, such as ambient temperature, can modulate Wolbachia density and maternal transmission. Finally, we assess the prospects of using Wolbachia to control other vectors and agricultural pest species.
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Affiliation(s)
- Eric P Caragata
- Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, Vero Beach, FL, USA.
| | - Heverton L C Dutra
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Pedro H F Sucupira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou - Fiocruz, Belo Horizonte, MG, Brazil
| | - Alvaro G A Ferreira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou - Fiocruz, Belo Horizonte, MG, Brazil
| | - Luciano A Moreira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou - Fiocruz, Belo Horizonte, MG, Brazil.
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22
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Leitner M, Bishop C, Asgari S. Transcriptional Response of Wolbachia to Dengue Virus Infection in Cells of the Mosquito Aedes aegypti. mSphere 2021; 6:e0043321. [PMID: 34190587 PMCID: PMC8265661 DOI: 10.1128/msphere.00433-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 06/07/2021] [Indexed: 11/20/2022] Open
Abstract
Aedes aegypti transmits one of the most significant mosquito-borne viruses, dengue virus (DENV). The absence of effective vaccines and clinical treatments and the emergence of insecticide resistance in A. aegypti necessitate novel vector control strategies. A new approach uses the endosymbiotic bacterium Wolbachia pipientis to reduce the spread of arboviruses. However, the Wolbachia-mediated antiviral mechanism is not well understood. To shed light on this mechanism, we investigated an unexplored aspect of Wolbachia-virus-mosquito interaction. We used RNA sequencing to examine the transcriptional response of Wolbachia to DENV infection in A. aegypti Aag2 cells transinfected with the wAlbB strain of Wolbachia. Our results suggest that genes encoding an endoribonuclease (RNase HI), a regulator of sigma 70-dependent gene transcription (6S RNA), essential cellular, transmembrane, and stress response functions and primary type I and IV secretion systems were upregulated, while a number of transport and binding proteins of Wolbachia, ribosome structure, and elongation factor-associated genes were downregulated due to DENV infection. Furthermore, bacterial retrotransposon, transposable, and phage-related elements were found among the up- and downregulated genes. We show that Wolbachia elicits a transcriptional response to virus infection and identify differentially expressed Wolbachia genes mostly at the early stages of virus infection. These findings highlight Wolbachia's ability to alter its gene expression in response to DENV infection of the host cell. IMPORTANCE Aedes aegypti is a vector of several pathogenic viruses, including dengue, Zika, chikungunya, and yellow fever viruses, which are of importance to human health. Wolbachia is an endosymbiotic bacterium currently used in transinfected mosquitoes to suppress replication and transmission of dengue viruses. However, the mechanism of Wolbachia-mediated virus inhibition is not fully understood. While several studies have shown mosquitoes' transcriptional responses to dengue virus infection, none have investigated these responses in Wolbachia, which may provide clues to the inhibition mechanism. Our results suggest changes in the expression of a number of functionally important Wolbachia genes upon dengue virus infection, including those involved in stress responses, providing insights into the endosymbiont's reaction to virus infection.
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Affiliation(s)
- Michael Leitner
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - Cameron Bishop
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - Sassan Asgari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, Australia
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23
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Rosendo Machado S, van der Most T, Miesen P. Genetic determinants of antiviral immunity in dipteran insects - Compiling the experimental evidence. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 119:104010. [PMID: 33476667 DOI: 10.1016/j.dci.2021.104010] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 01/08/2021] [Accepted: 01/09/2021] [Indexed: 06/12/2023]
Abstract
The genetic basis of antiviral immunity in dipteran insects is extensively studied in Drosophila melanogaster and advanced technologies for genetic manipulation allow a better characterization of immune responses also in non-model insect species. Especially, immunity in vector mosquitoes is recently in the spotlight, due to the medical impact that these insects have by transmitting viruses and other pathogens. Here, we review the current state of experimental evidence that supports antiviral functions for immune genes acting in different cellular pathways. We discuss the well-characterized RNA interference mechanism along with the less well-defined JAK-STAT, Toll, and IMD signaling pathways. Furthermore, we highlight the initial evidence for antiviral activity observed for the autophagy pathway, transcriptional pausing, as well as piRNA production from endogenous viral elements. We focus our review on studies from Drosophila and mosquito species from the lineages Aedes, Culex, and Anopheles, which contain major vector species responsible for virus transmission.
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Affiliation(s)
- Samara Rosendo Machado
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, the Netherlands
| | - Tom van der Most
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, the Netherlands
| | - Pascal Miesen
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, the Netherlands.
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24
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Trammell CE, Goodman AG. Host Factors That Control Mosquito-Borne Viral Infections in Humans and Their Vector. Viruses 2021; 13:v13050748. [PMID: 33923307 PMCID: PMC8145797 DOI: 10.3390/v13050748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/13/2021] [Accepted: 04/22/2021] [Indexed: 02/07/2023] Open
Abstract
Mosquito-borne viral infections are responsible for a significant degree of morbidity and mortality across the globe due to the severe diseases these infections cause, and they continue to increase each year. These viruses are dependent on the mosquito vector as the primary means of transmission to new vertebrate hosts including avian, livestock, and human populations. Due to the dynamic host environments that mosquito-borne viruses pass through as they are transmitted between vector and vertebrate hosts, there are various host factors that control the response to infection over the course of the pathogen's life cycle. In this review, we discuss these host factors that are present in either vector or vertebrate models during infection, how they vary or are conserved between hosts, and their implications in future research pertaining to disease prevention and treatment.
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Affiliation(s)
- Chasity E. Trammell
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99163, USA;
- NIH Protein Biotechnology Training Program, Washington State University, Pullman, WA 99164-6240, USA
| | - Alan G. Goodman
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99163, USA;
- Paul G. Allen School for Global Health, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
- Correspondence: ; Tel.: +1-(509)-335-0186
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25
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Abstract
Wolbachia is a maternally transmitted bacterium that manipulates arthropod and nematode biology in myriad ways. The Wolbachia strain colonizing Drosophila melanogaster creates sperm-egg incompatibilities and protects its host against RNA viruses, making it a promising tool for vector control. Despite successful trials using Wolbachia-transfected mosquitoes for dengue control, knowledge of how Wolbachia and viruses jointly affect insect biology remains limited. Using the Drosophila melanogaster model, transcriptomics and gene expression network analyses revealed pathways with altered expression and splicing due to Wolbachia colonization and virus infection. Included are metabolic pathways previously unknown to be important for Wolbachia-host interactions. Additionally, Wolbachia-colonized flies exhibit a dampened transcriptomic response to virus infection, consistent with early blocking of virus replication. Finally, using Drosophila genetics, we show that Wolbachia and expression of nucleotide metabolism genes have interactive effects on virus replication. Understanding the mechanisms of pathogen blocking will contribute to the effective development of Wolbachia-mediated vector control programs.IMPORTANCE Recently developed arbovirus control strategies leverage the symbiotic bacterium Wolbachia, which spreads in insect populations and blocks viruses from replicating. While this strategy has been successful, details of how this "pathogen blocking" works are limited. Here, we use a combination of virus infections, fly genetics, and transcriptomics to show that Wolbachia and virus interact at host nucleotide metabolism pathways.
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26
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Insulin Potentiates JAK/STAT Signaling to Broadly Inhibit Flavivirus Replication in Insect Vectors. Cell Rep 2020; 29:1946-1960.e5. [PMID: 31722209 PMCID: PMC6871768 DOI: 10.1016/j.celrep.2019.10.029] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/03/2019] [Accepted: 10/08/2019] [Indexed: 12/13/2022] Open
Abstract
The World Health Organization estimates that more than half of the world’s population is at risk for vector-borne diseases, including arboviruses. Because many arboviruses are mosquito borne, investigation of the insect immune response will help identify targets to reduce the spread of arboviruses. Here, we use a genetic screening approach to identify an insulin-like receptor as a component of the immune response to arboviral infection. We determine that vertebrate insulin reduces West Nile virus (WNV) replication in Drosophila melanogaster as well as WNV, Zika, and dengue virus titers in mosquito cells. Mechanistically, we show that insulin signaling activates the JAK/STAT, but not RNAi, pathway via ERK to control infection in Drosophila cells and Culex mosquitoes through an integrated immune response. Finally, we validate that insulin priming of adult female Culex mosquitoes through a blood meal reduces WNV infection, demonstrating an essential role for insulin signaling in insect antiviral responses to human pathogens. The world’s population is at risk for infection with several flaviviruses. Ahlers et al. use a living library of insects to determine that an insulin-like receptor controls West Nile virus infection. Insulin signaling is antiviral via the JAK/STAT pathway in both fly and mosquito models and against a range of flaviviruses.
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27
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Sucupira PHF, Ferreira ÁGA, Leite THJF, de Mendonça SF, Ferreira FV, Rezende FO, Marques JT, Moreira LA. The RNAi Pathway Is Important to Control Mayaro Virus Infection in Aedes aegypti but not for Wolbachia-Mediated Protection. Viruses 2020; 12:v12080871. [PMID: 32784948 PMCID: PMC7547387 DOI: 10.3390/v12080871] [Citation(s) in RCA: 6] [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: 06/22/2020] [Revised: 07/15/2020] [Accepted: 07/27/2020] [Indexed: 01/02/2023] Open
Abstract
Mayaro virus (MAYV), a sylvatic arbovirus belonging to the Togaviridae family and Alphavirus genus, is responsible for an increasing number of outbreaks in several countries of Central and South America. Despite Haemagogus janthinomys being identified as the main vector of MAYV, laboratory studies have already demonstrated the competence of Aedes aegypti to transmit MAYV. It has also been demonstrated that the WolbachiawMel strain is able to impair the replication and transmission of MAYV in Ae. aegypti. In Ae. aegypti, the small interfering RNA (siRNA) pathway is an important antiviral mechanism; however, it remains unclear whether siRNA pathway acts against MAYV infection in Ae. aegypti. The main objective of this study was to determine the contribution of the siRNA pathway in the control of MAYV infection. Thus, we silenced the expression of AGO2, an essential component of the siRNA pathway, by injecting dsRNA-targeting AGO2 (dsAGO2). Our results showed that AGO2 is required to control MAYV replication upon oral infection in Wolbachia-free Ae. aegypti. On the other hand, we found that Wolbachia-induced resistance to MAYV in Ae. aegypti is independent of the siRNA pathway. Our study brought new information regarding the mechanism of viral protection, as well as on Wolbachia mediated interference.
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Affiliation(s)
- Pedro H. F. Sucupira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou – Fiocruz, Belo Horizonte, MG 30190-002, Brazil; (P.H.F.S.); (Á.G.A.F.); (S.F.d.M.); (F.O.R.)
| | - Álvaro G. A. Ferreira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou – Fiocruz, Belo Horizonte, MG 30190-002, Brazil; (P.H.F.S.); (Á.G.A.F.); (S.F.d.M.); (F.O.R.)
| | - Thiago H. J. F. Leite
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, 6627-Pampulha-Belo Horizonte-MG, CEP 30270-901, Brazil; (T.H.J.F.L.); (F.V.F.); (J.T.M.)
| | - Silvana F. de Mendonça
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou – Fiocruz, Belo Horizonte, MG 30190-002, Brazil; (P.H.F.S.); (Á.G.A.F.); (S.F.d.M.); (F.O.R.)
| | - Flávia V. Ferreira
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, 6627-Pampulha-Belo Horizonte-MG, CEP 30270-901, Brazil; (T.H.J.F.L.); (F.V.F.); (J.T.M.)
| | - Fernanda O. Rezende
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou – Fiocruz, Belo Horizonte, MG 30190-002, Brazil; (P.H.F.S.); (Á.G.A.F.); (S.F.d.M.); (F.O.R.)
| | - João T. Marques
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, 6627-Pampulha-Belo Horizonte-MG, CEP 30270-901, Brazil; (T.H.J.F.L.); (F.V.F.); (J.T.M.)
- Université de Strasbourg, CNRS UPR9022, Inserm U1257, 67084 Strasbourg, France
| | - Luciano A. Moreira
- Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou – Fiocruz, Belo Horizonte, MG 30190-002, Brazil; (P.H.F.S.); (Á.G.A.F.); (S.F.d.M.); (F.O.R.)
- Correspondence: ; Tel.: +55-31-3349-7776
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28
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Ford SA, Albert I, Allen SL, Chenoweth SF, Jones M, Koh C, Sebastian A, Sigle LT, McGraw EA. Artificial Selection Finds New Hypotheses for the Mechanism of Wolbachia-Mediated Dengue Blocking in Mosquitoes. Front Microbiol 2020; 11:1456. [PMID: 32733407 PMCID: PMC7358395 DOI: 10.3389/fmicb.2020.01456] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 06/04/2020] [Indexed: 12/18/2022] Open
Abstract
Wolbachia is an intracellular bacterium that blocks virus replication in insects and has been introduced into the mosquito, Aedes aegypti for the biocontrol of arboviruses including dengue, Zika, and chikungunya. Despite ongoing research, the mechanism of Wolbachia-mediated virus blocking remains unclear. We recently used experimental evolution to reveal that Wolbachia-mediated dengue blocking could be selected upon in the A. aegypti host and showed evidence that strong levels of blocking could be maintained by natural selection. In this study, we investigate the genetic variation associated with blocking and use these analyses to generate testable hypotheses surrounding the mechanism of Wolbachia-mediated dengue blocking. From our results, we hypothesize that Wolbachia may block virus replication by increasing the regeneration rate of mosquito cells via the Notch signaling pathway. We also propose that Wolbachia modulates the host’s transcriptional pausing pathway either to prime the host’s anti-viral response or to directly inhibit viral replication.
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Affiliation(s)
- Suzanne A Ford
- Huck Institute of Life Sciences, Penn State University, University Park, PA, United States.,School of Biological Sciences, Monash University, Melbourne, VIC, Australia.,Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Istvan Albert
- Huck Institute of Life Sciences, Penn State University, University Park, PA, United States
| | - Scott L Allen
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia.,Institut für Populationsgenetik, Vetmeduni Vienna, Vienna, Austria
| | - Stephen F Chenoweth
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Matthew Jones
- Huck Institute of Life Sciences, Penn State University, University Park, PA, United States
| | - Cassandra Koh
- School of Biological Sciences, Monash University, Melbourne, VIC, Australia.,Department of Virology, Institut Pasteur, Paris, France
| | - Aswathy Sebastian
- Huck Institute of Life Sciences, Penn State University, University Park, PA, United States
| | - Leah T Sigle
- Huck Institute of Life Sciences, Penn State University, University Park, PA, United States
| | - Elizabeth A McGraw
- Huck Institute of Life Sciences, Penn State University, University Park, PA, United States.,School of Biological Sciences, Monash University, Melbourne, VIC, Australia
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29
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Haqshenas G, Terradas G, Paradkar PN, Duchemin JB, McGraw EA, Doerig C. A Role for the Insulin Receptor in the Suppression of Dengue Virus and Zika Virus in Wolbachia-Infected Mosquito Cells. Cell Rep 2020; 26:529-535.e3. [PMID: 30650347 DOI: 10.1016/j.celrep.2018.12.068] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 10/25/2018] [Accepted: 12/12/2018] [Indexed: 02/01/2023] Open
Abstract
Wolbachia-infected mosquitoes are refractory to super-infection with arthropod-borne pathogens, but the role of host cell signaling proteins in pathogen-blocking mechanisms remains to be elucidated. Here, we use an antibody microarray approach to provide a comprehensive picture of the signaling response of Aedes aegypti-derived cells to Wolbachia. This approach identifies the host cell insulin receptor as being downregulated by the bacterium. Furthermore, siRNA-mediated knockdown and treatment with a small-molecule inhibitor of the insulin receptor kinase concur to assign a crucial role for this enzyme in the replication of dengue and Zika viruses in cultured mosquito cells. Finally, we show that the production of Zika virus in Wolbachia-free live mosquitoes is impaired by treatment with the selective inhibitor mimicking Wolbachia infection. This study identifies Wolbachia-mediated downregulation of insulin receptor kinase activity as a mechanism contributing to the blocking of super-infection by arboviruses.
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Affiliation(s)
- Gholamreza Haqshenas
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC 3800, Australia.
| | - Gerard Terradas
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Prasad N Paradkar
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, VIC, Australia
| | - Jean-Bernard Duchemin
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, VIC, Australia
| | - Elizabeth A McGraw
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia; Department of Entomology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA 16802, USA.
| | - Christian Doerig
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC 3800, Australia.
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30
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Selection on Aedes aegypti alters Wolbachia-mediated dengue virus blocking and fitness. Nat Microbiol 2019; 4:1832-1839. [PMID: 31451771 DOI: 10.1038/s41564-019-0533-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 07/05/2019] [Indexed: 12/21/2022]
Abstract
The dengue, Zika and chikungunya viruses are transmitted by the mosquito Aedes aegypti and pose a substantial threat to global public health. Current vaccines and mosquito control strategies have limited efficacy, so novel interventions are needed1,2. Wolbachia are bacteria that inhabit insect cells and have been found to reduce viral infection-a phenotype that is referred to as viral 'blocking'3. Although not naturally found in A. aegypti4, Wolbachia were stably introduced into this mosquito in 20114,5 and were shown to reduce the transmission potential of dengue, Zika and chikungunya6,7. Subsequent field trials showed Wolbachia's ability to spread through A. aegypti populations and reduce the local incidence of dengue fever8. Despite these successes, the evolutionary stability of viral blocking is unknown. Here, we utilized artificial selection to reveal genetic variation in the mosquito that affects Wolbachia-mediated dengue blocking. We found that mosquitoes exhibiting weaker blocking also have reduced fitness, suggesting the potential for natural selection to maintain blocking. We also identified A. aegypti genes that affect blocking strength, shedding light on a possible mechanism for the trait. These results will inform the use of Wolbachia as biocontrol agents against mosquito-borne viruses and direct further research into measuring and improving their efficacy.
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31
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Caragata EP, Tikhe CV, Dimopoulos G. Curious entanglements: interactions between mosquitoes, their microbiota, and arboviruses. Curr Opin Virol 2019; 37:26-36. [PMID: 31176069 PMCID: PMC6768729 DOI: 10.1016/j.coviro.2019.05.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/03/2019] [Accepted: 05/06/2019] [Indexed: 11/22/2022]
Abstract
Mosquitoes naturally harbor a diverse community of microorganisms that play a crucial role in their biology. Mosquito-microbiota interactions are abundant and complex. They can dramatically alter the mosquito immune response, and impede or enhance a mosquito's ability to transmit medically important arboviral pathogens. Yet critically, given the massive public health impact of arboviral disease, few such interactions have been well characterized. In this review, we describe the current state of knowledge of the role of microorganisms in mosquito biology, how microbial-induced changes to mosquito immunity moderate infection with arboviruses, cases of mosquito-microbial-virus interactions with a defined mechanism, and the molecular interactions that underlie the endosymbiotic bacterium Wolbachia's ability to block virus infection in mosquitoes.
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Affiliation(s)
- Eric P Caragata
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Chinmay V Tikhe
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - George Dimopoulos
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States.
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32
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Using genetic variation in Aedes aegypti to identify candidate anti-dengue virus genes. BMC Infect Dis 2019; 19:580. [PMID: 31272403 PMCID: PMC6611004 DOI: 10.1186/s12879-019-4212-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 06/23/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Transcriptomic profiling has generated extensive lists of genes that respond to viral infection in mosquitoes. These gene lists contain two types of genes; (1) those that are responsible for the insect's natural antiviral defense mechanisms, including some known innate immunity genes, and (2) genes whose change in expression may occur simply as a result of infection. As genetic modification tools for mosquitoes continue to improve, the opportunities to make refractory insects via allelic replacement or delivery of small RNAs that alter gene expression are expanding. Therefore, the ability to identify which genes in transcriptional profiles may have immune function has increasing value. Arboviruses encounter a range of mosquito tissues and physiologies as they traverse from the midgut to the salivary glands. While the midgut is well-studied as the primary tissue barrier, antiviral genes expressed in the subsequent tissues of the carcass offer additional candidates for second stage intervention in the mosquito body. METHODS Mosquito lines collected recently from field populations exhibit natural genetic variation for dengue virus susceptibility. We sought to use a modified full-sib breeding design to identify mosquito families that varied in their dengue viral load in their bodies post infection. RESULTS By delivering virus intrathoracically, we bypassed the midgut and focused on whole body responses in order to evaluate carcass-associated refractoriness. We tested 25 candidate genes selected for their appearance in multiple published transcriptional profiles and were able to identify 12 whose expression varied with susceptibility in the genetic families. CONCLUSIONS This method, using natural genetic variation, offers a simple means to screen and reduce candidate gene lists prior to carrying out more labor-intensive functional studies. The extracted RNA from the females across the families represents a storable resource that can be used to screen subsequent candidate genes in the future. The aspect of vector competence being assessed could be varied by focusing on different tissues or time points post infection.
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33
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Koh C, Audsley MD, Di Giallonardo F, Kerton EJ, Young PR, Holmes EC, McGraw EA. Sustained Wolbachia-mediated blocking of dengue virus isolates following serial passage in Aedes aegypti cell culture. Virus Evol 2019; 5:vez012. [PMID: 31191980 PMCID: PMC6555872 DOI: 10.1093/ve/vez012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Wolbachia is an intracellular endosymbiont of insects that inhibits the replication of a range of pathogens in its arthropod hosts. The release of Wolbachia into wild populations of mosquitoes is an innovative biocontrol effort to suppress the transmission of arthropod-borne viruses (arboviruses) to humans, most notably dengue virus. The success of the Wolbachia-based approach hinges upon the stable persistence of the ‘pathogen blocking’ effect, whose mechanistic basis is poorly understood. Evidence suggests that Wolbachia may affect viral replication via a combination of competition for host resources and activation of host immunity. The evolution of resistance against Wolbachia and pathogen blocking in the mosquito or the virus could reduce the public health impact of the symbiont releases. Here, we investigate if dengue 3 virus (DENV-3) is capable of accumulating adaptive mutations that improve its replicative capacity during serial passage in Wolbachia wMel-infected cells. During the passaging regime, viral isolates in Wolbachia-infected cells exhibited greater variation in viral loads compared to controls. The viral loads of these isolates declined rapidly during passaging due to the blocking effects of Wolbachia carriage, with several being lost all together and the remainder recovering to low but stable levels. We attempted to sequence the genomes of the surviving passaged isolates but, given their low abundance, were unable to obtain sufficient depth of coverage for evolutionary analysis. In contrast, viral loads in Wolbachia-free control cells were consistently high during passaging. The surviving isolates passaged in the presence of Wolbachia exhibited a reduced ability to replicate even in Wolbachia-free cells. These experiments demonstrate the challenge for dengue in evolving resistance to Wolbachia-mediated blocking.
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Affiliation(s)
- Cassandra Koh
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Michelle D Audsley
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Francesca Di Giallonardo
- Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia.,Sydney Medical School, The University of Sydney, Camperdown, NSW, Australia.,The Kirby Institute, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Emily J Kerton
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Paul R Young
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Edward C Holmes
- Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia
| | - Elizabeth A McGraw
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.,Department of Entomology, Center for Infectious Disease Dynamics, Huck Institutes of the Life Sciences, Pennsylvania State University, State College, PA, USA
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Sigle LT, McGraw EA. Expanding the canon: Non-classical mosquito genes at the interface of arboviral infection. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 109:72-80. [PMID: 30970277 DOI: 10.1016/j.ibmb.2019.04.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/10/2019] [Accepted: 04/01/2019] [Indexed: 06/09/2023]
Abstract
Mosquito transmitted viruses cause significant morbidity and mortality in human populations. Despite the use of insecticides and other measures of vector control, arboviral diseases are on the rise. One potential solution for limiting disease transmission to humans is to render mosquitoes refractory to viral infection through genetic modification. Substantial research effort in Drosophila, Aedes and Anopheles has helped to define the major innate immune pathways, including Toll, IMD, Jak/Stat and RNAi, however we still have an incomplete picture of the mosquito antiviral response. Transcriptional profiles of virus-infected insects reveal a much wider range of pathways activated by the process of infection. Within these lists of genes are unexplored mosquito candidates of viral defense. Wolbachia species are endosymbiotic bacteria that naturally limit arboviral infection in mosquitoes. Our understanding of the Wolbachia-mediated viral blocking mechanism is poor, but it does not appear to operate via the classical immune pathways. Herein, we reviewed the transcriptomic response of mosquitoes to multiple viral species and put forth consensus gene types/families outside the immune canon whose expression responds to infection, including cytoskeleton and cellular trafficking, the heat shock response, cytochromes P450, cell proliferation, chitin and small RNAs. We then examine emerging evidence for their functional role in viral resistance in diverse insect and mammalian hosts and their potential role in Wolbachia-mediated viral blocking. These candidate gene families offer novel avenues for research into the nature of insect viral defense.
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Affiliation(s)
- Leah T Sigle
- Center for Infectious Disease Dynamics, Department of Entomology, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Elizabeth A McGraw
- Center for Infectious Disease Dynamics, Department of Entomology, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
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Caragata EP, Rocha MN, Pereira TN, Mansur SB, Dutra HLC, Moreira LA. Pathogen blocking in Wolbachia-infected Aedes aegypti is not affected by Zika and dengue virus co-infection. PLoS Negl Trop Dis 2019; 13:e0007443. [PMID: 31107912 PMCID: PMC6544317 DOI: 10.1371/journal.pntd.0007443] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 05/31/2019] [Accepted: 05/07/2019] [Indexed: 11/29/2022] Open
Abstract
Background Wolbachia’s ability to restrict arbovirus transmission makes it a promising tool to combat mosquito-transmitted diseases. Wolbachia-infected Aedes aegypti are currently being released in locations such as Brazil, which regularly experience concurrent outbreaks of different arboviruses. A. aegypti can become co-infected with, and transmit multiple arboviruses with one bite, which can complicate patient diagnosis and treatment. Methodology/principle findings Using experimental oral infection of A. aegypti and then RT-qPCR, we examined ZIKV/DENV-1 and ZIKV/DENV-3 co-infection in Wolbachia-infected A. aegypti and observed that Wolbachia-infected mosquitoes experienced lower prevalence of infection and viral load than wildtype mosquitoes, even with an extra infecting virus. Critically, ZIKV/DENV co-infection had no significant impact on Wolbachia’s ability to reduce viral transmission. Wolbachia infection also strongly altered expression levels of key immune genes Defensin C and Transferrin 1, in a virus-dependent manner. Conclusions/significance Our results suggest that pathogen interference in Wolbachia-infected A. aegypti is not adversely affected by ZIKV/DENV co-infection, which suggests that Wolbachia-infected A. aegypti will likely prove suitable for controlling mosquito-borne diseases in environments with complex patterns of arbovirus transmission. Wolbachia is an endosymbiotic bacterium that infects insects. It has been artificially transferred into Aedes aegypti, a mosquito species that can transmit medically important viruses including dengue, chikungunya, and Zika. Wolbachia in A. aegypti limits infection with these viruses, making the mosquitoes much less capable of transmitting them to people. In tropical areas, where these viral pathogens are commonly found, it is not unusual for outbreaks of different viruses to occur at the same time, which can complicate diagnosis and treatment for those afflicted. Mosquitoes with Wolbachia are currently being released into these areas to reduce transmission of these diseases. In our study, we assessed whether Wolbachia infection in A. aegypti mosquitoes could still effectively inhibit the dengue and Zika viruses if the mosquitoes were fed both viruses at the same time. We found that Wolbachia was still very effective at inhibiting the replication of both viruses in the mosquito, and likewise still greatly reduced the chance of transmission of either virus. Our results suggest that Wolbachia-infected mosquitoes should be able to limit infection with more than one virus, should they encounter them in the field.
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Affiliation(s)
- Eric P. Caragata
- Grupo Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou—Fiocruz, Belo Horizonte, MG, Brazil
| | - Marcele N. Rocha
- Grupo Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou—Fiocruz, Belo Horizonte, MG, Brazil
| | - Thiago N. Pereira
- Grupo Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou—Fiocruz, Belo Horizonte, MG, Brazil
| | - Simone B. Mansur
- Grupo Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou—Fiocruz, Belo Horizonte, MG, Brazil
| | - Heverton L. C. Dutra
- Grupo Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou—Fiocruz, Belo Horizonte, MG, Brazil
| | - Luciano A. Moreira
- Grupo Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou—Fiocruz, Belo Horizonte, MG, Brazil
- * E-mail:
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Parry R, Bishop C, De Hayr L, Asgari S. Density-dependent enhanced replication of a densovirus in Wolbachia-infected Aedes cells is associated with production of piRNAs and higher virus-derived siRNAs. Virology 2018; 528:89-100. [PMID: 30583288 DOI: 10.1016/j.virol.2018.12.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 11/20/2018] [Accepted: 12/05/2018] [Indexed: 02/03/2023]
Abstract
The endosymbiotic bacterium Wolbachia pipientis has been shown to restrict a range of RNA viruses in Drosophila melanogaster and transinfected dengue mosquito, Aedes aegypti. Here, we show that Wolbachia infection enhances replication of Aedes albopictus densovirus (AalDNV-1), a single stranded DNA virus, in Aedes cell lines in a density-dependent manner. Analysis of previously produced small RNAs of Aag2 cells showed that Wolbachia-infected cells produced greater absolute abundance of virus-derived short interfering RNAs compared to uninfected cells. Additionally, we found production of virus-derived PIWI-like RNAs (vpiRNA) produced in response to AalDNV-1 infection. Nuclear fractions of Aag2 cells produced a primary vpiRNA signature U1 bias whereas the typical "ping-pong" signature (U1 - A10) was evident in vpiRNAs from the cytoplasmic fractions. This is the first report of the density-dependent enhancement of DNA viruses by Wolbachia. Further, we report the generation of vpiRNAs in a DNA virus-host interaction for the first time.
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Affiliation(s)
- Rhys Parry
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Cameron Bishop
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Lachlan De Hayr
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Sassan Asgari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.
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37
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Koh C, Allen SL, Herbert RI, McGraw EA, Chenoweth SF. The Transcriptional Response of Aedes aegypti with Variable Extrinsic Incubation Periods for Dengue Virus. Genome Biol Evol 2018; 10:3141-3151. [PMID: 30335126 PMCID: PMC6278894 DOI: 10.1093/gbe/evy230] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2018] [Indexed: 12/22/2022] Open
Abstract
Dengue fever is the most prevalent arboviral disease globally. Dengue virus is transmitted primarily by the Aedes aegypti mosquito. One measure of the mosquito’s efficiency as a vector is the extrinsic incubation period (EIP), which is the time between the ingestion of viremic blood and the emergence of virions in the saliva. The longer it takes virus to infect the midgut and traverse to the saliva, the fewer opportunities the mosquito will have to transmit the pathogen over its lifetime. We have shown previously that EIP for dengue virus is highly heritable and that it is negatively correlated with vector lifespan. Here, we examined the transcriptional profiles for mosquitoes that varied in their EIP phenotype and identified pathways associated with either short or long EIP. We found that mosquitoes with short EIP have less active immune responses but higher levels of protein translation and calcium ion homeostasis and that mosquitoes with longer EIP may have slower metabolism. These findings indicate a complex interplay between calcium ion distribution, ribosome biogenesis, and metabolism and reveal potential pathways that could be modified to slow the rate of viral progression and hence limit lifetime transmission capability.
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Affiliation(s)
- Cassandra Koh
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Scott L Allen
- Department of Entomology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, United States
| | - Rosemarie I Herbert
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Elizabeth A McGraw
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia.,Department of Entomology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, United States
| | - Stephen F Chenoweth
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia
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38
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Grobler Y, Yun CY, Kahler DJ, Bergman CM, Lee H, Oliver B, Lehmann R. Whole genome screen reveals a novel relationship between Wolbachia levels and Drosophila host translation. PLoS Pathog 2018; 14:e1007445. [PMID: 30422992 PMCID: PMC6258568 DOI: 10.1371/journal.ppat.1007445] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 11/27/2018] [Accepted: 10/30/2018] [Indexed: 11/29/2022] Open
Abstract
Wolbachia is an intracellular bacterium that infects a remarkable range of insect hosts. Insects such as mosquitos act as vectors for many devastating human viruses such as Dengue, West Nile, and Zika. Remarkably, Wolbachia infection provides insect hosts with resistance to many arboviruses thereby rendering the insects ineffective as vectors. To utilize Wolbachia effectively as a tool against vector-borne viruses a better understanding of the host-Wolbachia relationship is needed. To investigate Wolbachia-insect interactions we used the Wolbachia/Drosophila model that provides a genetically tractable system for studying host-pathogen interactions. We coupled genome-wide RNAi screening with a novel high-throughput fluorescence in situ hybridization (FISH) assay to detect changes in Wolbachia levels in a Wolbachia-infected Drosophila cell line JW18. 1117 genes altered Wolbachia levels when knocked down by RNAi of which 329 genes increased and 788 genes decreased the level of Wolbachia. Validation of hits included in depth secondary screening using in vitro RNAi, Drosophila mutants, and Wolbachia-detection by DNA qPCR. A diverse set of host gene networks was identified to regulate Wolbachia levels and unexpectedly revealed that perturbations of host translation components such as the ribosome and translation initiation factors results in increased Wolbachia levels both in vitro using RNAi and in vivo using mutants and a chemical-based translation inhibition assay. This work provides evidence for Wolbachia-host translation interaction and strengthens our general understanding of the Wolbachia-host intracellular relationship.
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Affiliation(s)
- Yolande Grobler
- Department of Cell Biology, Howard Hughes Medical Institute and Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY, United States of America
| | - Chi Y. Yun
- High Throughput Biology Core, Skirball Institute at New York University Langone Medical Center, New York, NY, United States of America
| | - David J. Kahler
- High Throughput Biology Core, Skirball Institute at New York University Langone Medical Center, New York, NY, United States of America
| | - Casey M. Bergman
- Department of Genetics and Institute of Bioinformatics, University of Georgia, Athens, GA, United States of America
| | - Hangnoh Lee
- Section of Developmental Genomics, Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States of America
| | - Brian Oliver
- Section of Developmental Genomics, Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States of America
| | - Ruth Lehmann
- Department of Cell Biology, Howard Hughes Medical Institute and Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY, United States of America
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Abstract
Aedes mosquito-transmitted diseases, such as dengue, Zika and chikungunya, are becoming major global health emergencies while old threats, such as yellow fever, are re-emerging. Traditional control methods, which have focused on reducing mosquito populations through the application of insecticides or preventing breeding through removal of larval habitat, are largely ineffective, as evidenced by the increasing global disease burden. Here, we review novel mosquito population reduction and population modification approaches with a focus on control methods based on the release of mosquitoes, including the release of Wolbachia-infected mosquitoes and strategies to genetically modify the vector, that are currently under development and have the potential to contribute to a reversal of the current alarming disease trends.
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Affiliation(s)
- Heather A Flores
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, Australia
| | - Scott L O'Neill
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, Australia.
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40
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Bakhshi H, Failloux AB, Zakeri S, Raz A, Dinparast Djadid N. Mosquito-borne viral diseases and potential transmission blocking vaccine candidates. INFECTION GENETICS AND EVOLUTION 2018; 63:195-203. [PMID: 29842982 DOI: 10.1016/j.meegid.2018.05.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 05/23/2018] [Accepted: 05/24/2018] [Indexed: 01/17/2023]
Abstract
Mosquito-borne viral diseases (MBVDs) have a complex biological cycle involving vectors and vertebrate hosts. These viruses are responsible for many deadly diseases worldwide. Although MBVDs threaten mostly developing countries, there is growing evidence indicating that they are also of concern in western countries where local transmission of arboviruses such as West Nile, Zika, Chikungunya and Dengue viruses have been recently reported. The rapid rise in human infections caused by these viruses is attributed to rapid climate change and travel facilities. Usually, the only way to control these diseases relies on the control of vectors in the absence of licensed vaccines and specific treatments. However, the overuse of insecticides has led to the emergence of insecticide resistance in vector populations, posing significant challenges for their control. An alternative method for reducing MBVDs can be the use of Transmission Blocking Vaccines (TBVs) that limits viral infection at the mosquito vector stage. Some successes have been obtained confirming the potential application of TBVs against viruses; however, this approach remains at the developmental stage and still needs improvements. The present review aims to give an update on MBVDs and to discuss the application as well as usage of potential TBVs for the control of mosquito-borne viral infections.
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Affiliation(s)
- Hasan Bakhshi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran (PII), Tehran, Iran
| | - Anna-Bella Failloux
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
| | - Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran (PII), Tehran, Iran
| | - Abbasali Raz
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran (PII), Tehran, Iran
| | - Navid Dinparast Djadid
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran (PII), Tehran, Iran.
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41
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Tham HW, Balasubramaniam V, Ooi MK, Chew MF. Viral Determinants and Vector Competence of Zika Virus Transmission. Front Microbiol 2018; 9:1040. [PMID: 29875751 PMCID: PMC5974093 DOI: 10.3389/fmicb.2018.01040] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 05/02/2018] [Indexed: 12/16/2022] Open
Abstract
Zika virus (ZIKV) has emerged as a new global health threat. Since its first discovery in Zika forest in Uganda, this virus has been isolated from several mosquito species, including Aedes aegypti and Aedes albopictus. The geographical distribution of these mosquito species across tropical and subtropical regions has led to several outbreaks, including the recent pandemic in Brazil, followed by the Pacific islands and other areas of North and South America. This has gained attention of the scientific community to elucidate the epidemiology and transmission of ZIKV. Despite its strong attention on clinical aspects for healthcare professionals, the relationships between ZIKV and its principal vectors, A. aegypti and A. albopictus, have not gained substantial interest in the scientific research community. As such, this review aims to summarize the current knowledge on ZIKV tropism and some important mechanisms which may be employed by the virus for effective strategies on viral survival in mosquitoes. In addition, this review identifies the areas of research that should be placed attention to, for which to be exploited for novel mosquito control strategies.
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Affiliation(s)
- Hong-Wai Tham
- Biology Research Laboratory, Faculty of Pharmacy, SEGi University, Petaling Jaya, Malaysia
| | - Vinod Balasubramaniam
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Subang Jaya, Malaysia
| | - Man K. Ooi
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Subang Jaya, Malaysia
| | - Miaw-Fang Chew
- Centre for Virus and Vaccine Research, School of Science and Technology, Sunway University, Subang Jaya, Malaysia
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42
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Abstract
Mosquito-transmitted viruses are spread globally and present a great risk to human health. Among the many approaches investigated to limit the diseases caused by these viruses are attempts to make mosquitos resistant to virus infection. Coinfection of mosquitos with the bacterium Wolbachia pipientis from supergroup A is a recent strategy employed to reduce the capacity for major vectors in the Aedes mosquito genus to transmit viruses, including dengue virus (DENV), Chikungunya virus (CHIKV), and Zika virus (ZIKV). Recently, a supergroup B Wolbachia wStri, isolated from Laodelphax striatellus, was shown to inhibit multiple lineages of ZIKV in Aedes albopictus cells. Here, we show that wStri blocks the growth of positive-sense RNA viruses DENV, CHIKV, ZIKV, and yellow fever virus by greater than 99.9%. wStri presence did not affect the growth of the negative-sense RNA viruses LaCrosse virus or vesicular stomatitis virus. Investigation of the stages of the ZIKV life cycle inhibited by wStri identified two distinct blocks in viral replication. We found a reduction of ZIKV entry into wStri-infected cells. This was partially rescued by the addition of a cholesterol-lipid supplement. Independent of entry, transfected viral genome was unable to replicate in Wolbachia-infected cells. RNA transfection and metabolic labeling studies suggested that this replication defect is at the level of RNA translation, where we saw a 66% reduction in mosquito protein synthesis in wStri-infected cells. This study’s findings increase the potential for application of wStri to block additional arboviruses and also identify specific blocks in viral infection caused by Wolbachia coinfection. Dengue, Zika, and yellow fever viruses are mosquito-transmitted diseases that have spread throughout the world, causing millions of infections and thousands of deaths each year. Existing programs that seek to contain these diseases through elimination of the mosquito population have so far failed, making it crucial to explore new ways of limiting the spread of these viruses. Here, we show that introduction of an insect symbiont Wolbachia wStri, into mosquito cells is highly effective at reducing yellow fever virus, dengue virus, Zika virus, and Chikungunya virus production. Reduction of virus replication was attributable to decreases in entry and a strong block of virus gene expression at the translational level. These findings expand the potential use of Wolbachia wStri to block viruses and identify two separate steps for limiting virus replication in mosquitos that could be targeted via microbes or other means as an antiviral strategy.
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43
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Dual Insect specific virus infection limits Arbovirus replication in Aedes mosquito cells. Virology 2018; 518:406-413. [PMID: 29625404 DOI: 10.1016/j.virol.2018.03.022] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/21/2018] [Accepted: 03/23/2018] [Indexed: 11/20/2022]
Abstract
Aedes mosquitoes are vectors for many pathogenic viruses. Cell culture systems facilitate the investigation of virus growth in the mosquito vector. We found Zika virus (ZIKV) growth to be consistent in A. albopictus cells but hypervariable in A. aegypti cell lines. As a potential explanation of this variability, we tested the hypothesis that our cells harbored opportunistic viruses. We screened Aedes cell lines for the presence of insect specific viruses (ISVs), Cell-fusing agent virus (CFAV) and Phasi charoen-like virus (PCLV). PCLV was present in the ZIKV-growth-variable A. aegypti cell lines but absent in A. albopictus lines, suggesting that these ISVs may interfere with ZIKV growth. In support of this hypothesis, PCLV infection of CFAV-positive A. albopictus cells inhibited the growth of ZIKV, dengue virus and La Crosse virus. These data suggest ISV infection of cell lines can impact arbovirus growth leading to significant changes in cell permissivity to arbovirus infection.
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Conflict in the Intracellular Lives of Endosymbionts and Viruses: A Mechanistic Look at Wolbachia-Mediated Pathogen-blocking. Viruses 2018; 10:v10040141. [PMID: 29561780 PMCID: PMC5923435 DOI: 10.3390/v10040141] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 03/14/2018] [Accepted: 03/20/2018] [Indexed: 12/16/2022] Open
Abstract
At the forefront of vector control efforts are strategies that leverage host-microbe associations to reduce vectorial capacity. The most promising of these efforts employs Wolbachia, a maternally transmitted endosymbiotic bacterium naturally found in 40% of insects. Wolbachia can spread through a population of insects while simultaneously inhibiting the replication of viruses within its host. Despite successes in using Wolbachia-transfected mosquitoes to limit dengue, Zika, and chikungunya transmission, the mechanisms behind pathogen-blocking have not been fully characterized. Firstly, we discuss how Wolbachia and viruses both require specific host-derived structures, compounds, and processes to initiate and maintain infection. There is significant overlap in these requirements, and infection with either microbe often manifests as cellular stress, which may be a key component of Wolbachia’s anti-viral effect. Secondly, we discuss the current understanding of pathogen-blocking through this lens of cellular stress and develop a comprehensive view of how the lives of Wolbachia and viruses are fundamentally in conflict with each other. A thorough understanding of the genetic and cellular determinants of pathogen-blocking will significantly enhance the ability of vector control programs to deploy and maintain effective Wolbachia-mediated control measures.
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45
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Abstract
The power and ease of Drosophila genetics and the medical relevance of mosquito-transmitted viruses have made dipterans important model organisms in antiviral immunology. Studies of virus-host interactions at the molecular and population levels have illuminated determinants of resistance to virus infection. Here, we review the sources and nature of variation in antiviral immunity and virus susceptibility in model dipteran insects, specifically the fruit fly Drosophila melanogaster and vector mosquitoes of the genera Aedes and Culex. We first discuss antiviral immune mechanisms and describe the virus-specificity of these responses. In the following sections, we review genetic and microbiota-dependent variation in antiviral immunity. In the final sections, we explore less well-studied sources of variation, including abiotic factors, sexual dimorphism, infection history, and endogenous viral elements. We borrow from work on other pathogen types and non-dipteran species when it parallels or complements studies in dipterans. Understanding natural variation in virus-host interactions may lead to the identification of novel restriction factors and immune mechanisms and shed light on the molecular determinants of vector competence.
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Affiliation(s)
- William H Palmer
- Institute of Evolutionary Biology and Centre for Infection, Evolution and Immunity, University of Edinburgh, Edinburgh EH9 3FL UK.
| | - Finny S Varghese
- Department of Medical Microbiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, P.O. Box 9101, Nijmegen 6500 HB, The Netherlands.
- Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen 6525 GA, The Netherlands.
| | - Ronald P van Rij
- Department of Medical Microbiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, P.O. Box 9101, Nijmegen 6500 HB, The Netherlands.
- Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen 6525 GA, The Netherlands.
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Wolbachia-mediated virus blocking in mosquito cells is dependent on XRN1-mediated viral RNA degradation and influenced by viral replication rate. PLoS Pathog 2018; 14:e1006879. [PMID: 29494679 PMCID: PMC5833283 DOI: 10.1371/journal.ppat.1006879] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 01/15/2018] [Indexed: 12/14/2022] Open
Abstract
Wolbachia is currently being developed as a novel tool to block the transmission of dengue viruses (DENV) by Aedes aegypti. A number of mechanisms have been proposed to explain the DENV-blocking phenotype in mosquitoes, including competition for fatty acids like cholesterol, manipulation of host miRNAs and upregulation of innate immune pathways in the mosquito. We examined the various stages in the DENV infection process to better understand the mechanism of Wolbachia-mediated virus blocking (WMVB). Our results suggest that infection with Wolbachia does not inhibit DENV binding or cell entry, but reduces virus replication. In contrast to a previous report, we also observed a similar reduction in replication of West Nile virus (WNV). This reduced replication is associated with rapid viral RNA degradation in the cytoplasm. We didn't find a role for host miRNAs in WMVB. Further analysis showed that the 3' end of the virus subgenomic RNA was protected and accumulated over time suggesting that the degradation is XRN1-mediated. We also found that sub genomic flavivirus RNA accumulation inactivated XRN1 in mosquito cells in the absence of Wolbachia and led to enhancement of RNA degradation in its presence. Depletion of XRN1 decreased WMVB which was associated with a significant increase in DENV RNA. We also observed that WMVB is influenced by virus MOI and rate of virus replication. A comparatively elevated blocking was observed for slowly replicating DENV, compared to WNV. Similar results were obtained while analysing different DENV serotypes.
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47
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Schultz MJ, Connor JH, Frydman HM. Group B Wolbachia Strain-Dependent Inhibition of Arboviruses. DNA Cell Biol 2018; 37:2-6. [PMID: 29297702 DOI: 10.1089/dna.2017.4025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Mosquito-borne viruses, including Zika virus (ZIKV) and dengue virus (DENV), are global threats that continue to infect millions annually. Historically, efforts to combat the spread of these diseases have sought to eradicate the mosquito population. This has had limited success. Recent efforts to combat the spread of these diseases have targeted the mosquito population and the mosquito's ability to transmit viruses by altering the mosquito's microbiome. The introduction of particular strains of Wolbachia bacteria into mosquitos suppresses viral growth and blocks disease transmission. This novel strategy is being tested worldwide to reduce DENV and has early indications of success. The Wolbachia genus comprised divergent strains that are divided in major phylogenetic clades termed supergroups. All Wolbachia field trials currently utilize supergroup A Wolbachia in Aedes aegypti mosquitos to limit virus transmission. Here we discuss our studies of Wolbachia strains not yet used in virus control strategies but that show strong potential to reduce ZIKV replication. These strains are important opportunities in the search for novel tools to reduce the levels of mosquito-borne viruses and provide additional models for mechanistic studies.
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Affiliation(s)
- Michaela J Schultz
- 1 Department of Biology, Boston University , Boston Massachusetts.,2 National Emerging Infectious Diseases Laboratories, Boston University , Boston, Massachusetts
| | - John H Connor
- 2 National Emerging Infectious Diseases Laboratories, Boston University , Boston, Massachusetts.,3 Department of Microbiology, Boston University School of Medicine , Boston, Massachusetts
| | - Horacio M Frydman
- 1 Department of Biology, Boston University , Boston Massachusetts.,2 National Emerging Infectious Diseases Laboratories, Boston University , Boston, Massachusetts
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Mosquitoes as Arbovirus Vectors: From Species Identification to Vector Competence. PARASITOLOGY RESEARCH MONOGRAPHS 2018. [PMCID: PMC7122353 DOI: 10.1007/978-3-319-94075-5_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mosquitoes and other arthropods transmit a large number of medically important pathogens, in particular viruses. These arthropod-borne viruses (arboviruses) include a wide variety of RNA viruses belonging to the Flaviviridae family (West Nile virus (WNV), Usutu virus (USUV), Dengue virus (DENV), Japanese encephalitis virus (JEV), Zika virus (ZIKV)), the Togaviridae family (Chikungunya virus (CHIKV)), and Bunyavirales order (Rift Valley fever virus (RVFV)) (please refer also to Table 9.1). Arboviral transmission to humans and livestock constitutes a major threat to public health and economy as illustrated by the emergence of ZIKV in the Americas, RVFV outbreaks in Africa, and the worldwide outbreaks of DENV. To answer the question if those viral pathogens also pose a risk to Europe, we need to first answer the key questions (summarized in Fig. 9.1):Who could contribute to such an outbreak? Information about mosquito species resident or imported, potential hosts and viruses able to infect vectors and hosts in Germany is needed. Where would competent mosquito species meet favorable conditions for transmission? Information on the minimum requirements for efficient replication of the virus in a given vector species and subsequent transmission is needed. How do viruses and vectors interact to facilitate transmission? Information on the vector immunity, vector physiology, vector genetics, and vector microbiomes is needed.
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49
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Terradas G, Allen SL, Chenoweth SF, McGraw EA. Family level variation in Wolbachia-mediated dengue virus blocking in Aedes aegypti. Parasit Vectors 2017; 10:622. [PMID: 29282144 PMCID: PMC5746003 DOI: 10.1186/s13071-017-2589-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 12/12/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The mosquito vector Aedes aegypti is responsible for transmitting a range of arboviruses including dengue (DENV) and Zika (ZIKV). The global reach of these viruses is increasing due to an expansion of the mosquito's geographic range and increasing urbanization and human travel. Vector control remains the primary means for limiting these diseases. Wolbachia pipientis is an endosymbiotic bacterium of insects that has the ability to block the replication of pathogens, including flaviviruses such as DENV or ZIKV, inside the body of the vector. A strain of Wolbachia called wMel is currently being released into wild mosquito populations to test its potential to limit virus transmission to humans. The mechanism that underpins the virus blocking effect, however, remains elusive. METHODS We used a modified full-sib breeding design in conjunction with vector competence assays in wildtype and wMel-infected Aedes aegypti collected from the field. All individuals were injected with DENV-2 intrathoracically at 5-6 days of age. Tissues were dissected 7 days post-infection to allow quantification of DENV and Wolbachia loads. RESULTS We show the first evidence of family level variation in Wolbachia-mediated blocking in mosquitoes. This variation may stem from either genetic contributions from the mosquito and Wolbachia genomes or environmental influences on Wolbachia. In these families, we also tested for correlations between strength of blocking and expression level for several insect immunity genes with possible roles in blocking, identifying two genes of interest (AGO2 and SCP-2). CONCLUSIONS In this study we show variation in Wolbachia-mediated DENV blocking in Aedes aegypti that may arise from genetic contributions and environmental influences on the mosquito-Wolbachia association. This suggests that Wolbachia-mediated blocking may have the ability to evolve through time or be expressed differentially across environments. The long-term efficacy of Wolbachia in the field will be dependent on the stability of blocking. Understanding the mechanism of blocking will be necessary for successful development of strategies that counter the emergence of evolved resistance or variation in its expression under diverse field conditions.
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Affiliation(s)
- Gerard Terradas
- School of Biological Sciences, Monash University, Clayton, Melbourne, VIC, Australia
| | - Scott L Allen
- School of Biological Sciences, The University of Queensland, QLD, St. Lucia, Australia
| | - Stephen F Chenoweth
- School of Biological Sciences, The University of Queensland, QLD, St. Lucia, Australia
| | - Elizabeth A McGraw
- School of Biological Sciences, Monash University, Clayton, Melbourne, VIC, Australia.
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50
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Pan X, Pike A, Joshi D, Bian G, McFadden MJ, Lu P, Liang X, Zhang F, Raikhel AS, Xi Z. The bacterium Wolbachia exploits host innate immunity to establish a symbiotic relationship with the dengue vector mosquito Aedes aegypti. ISME JOURNAL 2017; 12:277-288. [PMID: 29099491 PMCID: PMC5739022 DOI: 10.1038/ismej.2017.174] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/30/2017] [Accepted: 09/06/2017] [Indexed: 01/15/2023]
Abstract
A host's immune system plays a central role in shaping the composition of the microbiota and, in return, resident microbes influence immune responses. Symbiotic associations of the maternally transmitted bacterium Wolbachia occur with a wide range of arthropods. It is, however, absent from the dengue and Zika vector mosquito Aedes aegypti in nature. When Wolbachia is artificially forced to form symbiosis with this new mosquito host, it boosts the basal immune response and enhances the mosquito's resistance to pathogens, including dengue, Zika virus and malaria parasites. The mechanisms involved in establishing a symbiotic relationship between Wolbachia and A. aegypti, and the long-term outcomes of this interaction, are not well understood. Here, we have demonstrated that both the immune deficiency (IMD) and Toll pathways are activated by the Wolbachia strain wAlbB upon its introduction into A. aegypti. Silencing the Toll and IMD pathways via RNA interference reduces the wAlbB load. Notably, wAlbB induces peptidoglycan recognition protein (PGRP)-LE expression in the carcass of A. aegypti, and its silencing results in a reduction of symbiont load. Using transgenic mosquitoes with stage-specific induction of the IMD and Toll pathways, we have shown that elevated wAlbB infection in these mosquitoes is maintained via maternal transmission. These results indicate that host innate immunity is utilized to establish and promote host-microbial symbiosis. Our results will facilitate a long-term projection of the stability of the Wolbachia-A. aegypti mosquito system that is being developed to control dengue and Zika virus transmission to humans.
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Affiliation(s)
- Xiaoling Pan
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.,School of Medicine, Hunan Normal University, Changsha, Hunan 410013, China
| | - Andrew Pike
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Deepak Joshi
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Guowu Bian
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Michael J McFadden
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Peng Lu
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Xiao Liang
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Fengrui Zhang
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Alexander S Raikhel
- Department of Entomology and Institute for Integrative Molecular Biology, University of California, Riverside, CA 92521, USA
| | - Zhiyong Xi
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.,Sun Yat-sen University-Michigan State University Joint Center of Vector Control for Tropical Diseases, Guangzhou, Guangdong 510080, China
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