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Marano JM, Weger-Lucarelli J. Preexisting inter-serotype immunity drives antigenic evolution of dengue virus serotype 2. Virology 2024; 590:109951. [PMID: 38096749 PMCID: PMC10855010 DOI: 10.1016/j.virol.2023.109951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/10/2023] [Accepted: 11/21/2023] [Indexed: 01/03/2024]
Abstract
Dengue virus (DENV) infects roughly 400 million people annually, causing febrile and hemorrhagic disease. While preexisting inter-serotype immunity (PISI) provides transient protection, it may drive severe disease over time. PISI's impact on virus evolution, however, is less understood. Retrospective epidemiological analyses suggest that PISI may drive DENV evolution. Using in vitro directed evolution, we explored how DENV2 evolves in the presence of DENV3/4 convalescent serum. Two post-passaging mutations (E-I6M and E-N203D) were then studied for fitness effects in mammalian and insect hosts and immune escape. E-I6M resisted neutralization, altered fitness in mammalian cell culture models, and had no effect in Aedes albopictus mosquitoes. E-N203D showed no change in neutralization sensitivity, reduced fitness in a DENV-naïve epithelial model, and no effects in the other models. These results align with surveillance data, where E-I6M emerged and disappeared, while E-203D and E-203 N cocirculate, thus suggesting that PISI can drive DENV evolution.
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Affiliation(s)
- Jeffrey M Marano
- Translational Biology, Medicine, and Health Graduate Program, Virginia Tech, Roanoke, VA, United States; Department of Biomedical Sciences and Pathobiology, Virginia Tech, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA, United States; Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA, United States
| | - James Weger-Lucarelli
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA, United States; Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA, United States.
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2
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Rozo-Lopez P, Drolet BS. Culicoides-Specific Fitness Increase of Vesicular Stomatitis Virus in Insect-to-Insect Infections. INSECTS 2024; 15:34. [PMID: 38249040 PMCID: PMC10816812 DOI: 10.3390/insects15010034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 01/23/2024]
Abstract
Vesicular stomatitis virus (VSV) is an arthropod-borne virus affecting livestock. In the United States, sporadic outbreaks result in significant economic losses. During epizootics, Culicoides biting midges are biological vectors and key to the geographic expansion of outbreaks. Additionally, Culicoides may play a role in VSV overwintering because females and males are capable of highly efficient venereal transmission, despite their relatively low virus titers. We hypothesized that VSV propagated within a midge has increased fitness for subsequent midge infections. To evaluate the potential host-specific fitness increase, we propagated three viral isolates of VSV in porcine skin fibroblasts and Culicoides cell lines. We then evaluated the viral infection dynamics of the different cell-source groups in Culicoides sonorensis. Our results indicate that both mammalian- and insect-derived VSV replicate well in midges inoculated via intrathoracic injection, thereby bypassing the midgut barriers. However, when the virus was required to infect and escape the midgut barrier to disseminate after oral acquisition, the insect-derived viruses had significantly higher titers, infection, and dissemination rates than mammalian-derived viruses. Our research suggests that VSV replication in Culicoides cells increases viral fitness, facilitating midge-to-midge transmission and subsequent replication, and further highlights the significance of Culicoides midges in VSV maintenance and transmission dynamics.
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Affiliation(s)
- Paula Rozo-Lopez
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
| | - Barbara S. Drolet
- Arthropod-Borne Animal Diseases Research Unit, United States Department of Agriculture, Manhattan, KS 66502, USA
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3
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Jaeger AS, Marano J, Riemersma KK, Castaneda D, Pritchard EM, Pritchard JC, Bohm EK, Baczenas JJ, O'Connor SL, Weger-Lucarelli J, Friedrich TC, Aliota MT. Gain without pain: adaptation and increased virulence of Zika virus in vertebrate host without fitness cost in mosquito vector. J Virol 2023; 97:e0116223. [PMID: 37800949 PMCID: PMC10653995 DOI: 10.1128/jvi.01162-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 08/21/2023] [Indexed: 10/07/2023] Open
Abstract
IMPORTANCE Previously, we modeled direct transmission chains of Zika virus (ZIKV) by serially passaging ZIKV in mice and mosquitoes and found that direct mouse transmission chains selected for viruses with increased virulence in mice and the acquisition of non-synonymous amino acid substitutions. Here, we show that these same mouse-passaged viruses also maintain fitness and transmission capacity in mosquitoes. We used infectious clone-derived viruses to demonstrate that the substitution in nonstructural protein 4A contributes to increased virulence in mice.
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Affiliation(s)
- Anna S. Jaeger
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities, Minnesota, USA
| | - Jeffrey Marano
- Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
| | - Kasen K. Riemersma
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - David Castaneda
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities, Minnesota, USA
| | - Elise M. Pritchard
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities, Minnesota, USA
| | - Julia C. Pritchard
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities, Minnesota, USA
| | - Ellie K. Bohm
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities, Minnesota, USA
| | - John J. Baczenas
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Shelby L. O'Connor
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - James Weger-Lucarelli
- Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
| | - Thomas C. Friedrich
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Matthew T. Aliota
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities, Minnesota, USA
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Molina BF, Marques NN, Bittar C, Batista MN, Rahal P. African ZIKV lineage fails to sustain infectivity in an in vitro mimetic urban cycle. Braz J Microbiol 2023; 54:1421-1431. [PMID: 37458982 PMCID: PMC10484821 DOI: 10.1007/s42770-023-01053-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 06/27/2023] [Indexed: 09/10/2023] Open
Abstract
Zika virus (ZIKV) is an arbovirus maintained in nature in two distinct cycles of transmission: urban and sylvatic. Each cycle includes specific vertebrate and invertebrate hosts, and through alternate infections, a conserved consensus sequence is maintained that might vary depending on the cycle. The current study aimed to investigate the ability of ZIKVAF and ZIKVBR to maintain an infectious cycle by alternating passages in cells mimicking the urban (UC) and semi-sylvatic (SC) cycles. The complete genome of the original inoculum and the last passages for each cycle were sequenced by Sanger. Ten passages were performed, as planned, for ZIKVBR UC, ZIKVAF SC, and ZIKVBR SC. ZIKVBR SC showed significant variation in viral titers along the passages, suggesting that the virus is not well adapted to the non-human primate host. ZIKVAF passage in UC was abrogated in the third passage, showing the inability of the African lineage to sustain cycles in human cells, suggesting a low capacity to establish an urban cycle. Several mutations were found in both strains along the passages, but not occurring at equivalent positions. Further studies are needed to elucidate whether any of these specific mutations affect viral fitness. ZIKV strains behave differently in artificial transmission cycles in vitro: Brazilian ZIKV was able to establish urban and semi-sylvatic cycles in vitro. African ZIKV proved unable to cycle among human and mosquito cells and is compatible only with the semi-sylvatic cycle. The main mutations arose in the NS2A region after artificial transmission cycles for both ZIKV strains but not at equivalent positions.
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Affiliation(s)
- Bárbara Floriano Molina
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
| | - Nayara Nathiê Marques
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
| | - Cíntia Bittar
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
- The Rockefeller University, 1230 York Ave, Manhattan, New York, NY 10065 USA
| | | | - Paula Rahal
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
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5
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Lange RE, Dupuis AP, Ciota AT. Diversification of Bourbon Virus in New York State. Microorganisms 2023; 11:1590. [PMID: 37375092 DOI: 10.3390/microorganisms11061590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 06/08/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
Bourbon virus (BRBV, family Orthomyxoviridae) is a tickborne virus recently detected in the United States (US). BRBV was first identified from a fatal human case in 2014 in Bourbon County, Kansas. Enhanced surveillance in Kansas and Missouri implicated Amblyomma americanum as the primary vector for BRBV. Historically, BRBV was only detected in the lower midwestern US, but since 2020 it has been reported in North Carolina, Virginia, New Jersey, and New York State (NYS). This study aimed to elucidate genetic and phenotypic characteristics of BRBV strains from NYS through whole genome sequencing and the assessment of replication kinetics in mammalian cultures and A. americanum nymphs. Sequence analysis revealed the existence of two divergent BRBV clades circulating in NYS. BRBV NY21-2143 is closely related to the midwestern BRBV strains but has unique substitutions in the glycoprotein. Two other NYS BRBV strains, BRBV NY21-1814 and BRBV NY21-2666, form a distinct clade unique from previously sequenced BRBV strains. Phenotypic diversification was also detected in NYS BRBV strains compared to each other and midwestern BRBV strains, with BRBV NY21-2143 displaying attenuation in rodent-derived cell culture and a fitness advantage in experimentally infected A. americanum. These data suggest genetic and phenotypic diversification of emergent BRBV strains circulating in NYS that could contribute to increased spread of BRBV in the northeastern US.
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Affiliation(s)
- Rachel E Lange
- Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, 1 University Place, Rensselaer, NY 12144, USA
- Wadsworth Center, New York State Department of Health, Griffin Laboratory, 5668 State Farm Road, Slingerlands, NY 12159, USA
| | - Alan P Dupuis
- Wadsworth Center, New York State Department of Health, Griffin Laboratory, 5668 State Farm Road, Slingerlands, NY 12159, USA
| | - Alexander T Ciota
- Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, 1 University Place, Rensselaer, NY 12144, USA
- Wadsworth Center, New York State Department of Health, Griffin Laboratory, 5668 State Farm Road, Slingerlands, NY 12159, USA
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Talmi-Frank D, Byas AD, Murrieta R, Weger-Lucarelli J, Rückert C, Gallichotte EN, Yoshimoto JA, Allen C, Bosco-Lauth AM, Graham B, Felix TA, Brault AC, Ebel GD. Intracellular Diversity of WNV within Circulating Avian Peripheral Blood Mononuclear Cells Reveals Host-Dependent Patterns of Polyinfection. Pathogens 2023; 12:767. [PMID: 37375457 DOI: 10.3390/pathogens12060767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
Arthropod-borne virus (arbovirus) populations exist as mutant swarms that are maintained between arthropods and vertebrates. West Nile virus (WNV) population dynamics are host-dependent. In American crows, purifying selection is weak and population diversity is high compared to American robins, which have 100- to 1000-fold lower viremia. WNV passed in robins leads to fitness gains, whereas that passed in crows does not. Therefore, we tested the hypothesis that high crow viremia allows for higher genetic diversity within individual avian peripheral blood mononuclear cells (PBMCs), reasoning that this could have produced the previously observed host-specific differences in genetic diversity and fitness. Specifically, we infected cells and birds with a molecularly barcoded WNV and sequenced viral RNA from single cells to quantify the number of WNV barcodes in each. Our results demonstrate that the richness of WNV populations within crows far exceeds that in robins. Similarly, rare WNV variants were maintained by crows more frequently than by robins. Our results suggest that increased viremia in crows relative to robins leads to the maintenance of defective genomes and less prevalent variants, presumably through complementation. Our findings further suggest that weaker purifying selection in highly susceptible crows is attributable to this higher viremia, polyinfections and complementation.
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Affiliation(s)
- Dalit Talmi-Frank
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Alex D Byas
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Reyes Murrieta
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - James Weger-Lucarelli
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Claudia Rückert
- Department of Biochemistry and Molecular Biology, College of Agriculture, Biotechnology & Natural Resources, University of Nevada, Reno, NV 89557, USA
| | - Emily N Gallichotte
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Janna A Yoshimoto
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Chris Allen
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Angela M Bosco-Lauth
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Barbara Graham
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Todd A Felix
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Lakewood, CO 80228, USA
| | - Aaron C Brault
- Division of Vector-Borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA
| | - Gregory D Ebel
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
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Jaeger AS, Marano J, Riemersma K, Castañeda D, Pritchard E, Pritchard J, Bohm EK, Baczenas JJ, O’Connor SL, Weger-Lucarelli J, Friedrich TC, Aliota MT. Gain without pain: Adaptation and increased virulence of Zika virus in vertebrate host without fitness cost in mosquito vector. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533515. [PMID: 36993525 PMCID: PMC10055270 DOI: 10.1101/2023.03.20.533515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Zika virus (ZIKV) is now in a post-pandemic period, for which the potential for re-emergence and future spread is unknown. Adding to this uncertainty is the unique capacity of ZIKV to directly transmit between humans via sexual transmission. Recently, we demonstrated that direct transmission of ZIKV between vertebrate hosts leads to rapid adaptation resulting in enhanced virulence in mice and the emergence of three amino acid substitutions (NS2A-A117V, NS2A-A117T, and NS4A-E19G) shared among all vertebrate-passaged lineages. Here, we further characterized these host-adapted viruses and found that vertebrate-passaged viruses also have enhanced transmission potential in mosquitoes. To understand the contribution of genetic changes to the enhanced virulence and transmission phenotype, we engineered these amino acid substitutions, singly and in combination, into a ZIKV infectious clone. We found that NS4A-E19G contributed to the enhanced virulence and mortality phenotype in mice. Further analyses revealed that NS4A-E19G results in increased neurotropism and distinct innate immune signaling patterns in the brain. None of the substitutions contributed to changes in transmission potential in mosquitoes. Together, these findings suggest that direct transmission chains could enable the emergence of more virulent ZIKV strains without compromising mosquito transmission capacity, although the underlying genetics of these adaptations are complex.
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Affiliation(s)
- Anna S. Jaeger
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities
| | - Jeffrey Marano
- Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University
| | - Kasen Riemersma
- Department of Pathobiological Sciences, University of Wisconsin-Madison
| | - David Castañeda
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities
| | - Elise Pritchard
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities
| | - Julia Pritchard
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities
| | - Ellie K. Bohm
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities
| | - John J. Baczenas
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, United States
- Wisconsin National Primate Research Center, University of Wisconsin-Madison
| | - Shelby L. O’Connor
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, United States
- Wisconsin National Primate Research Center, University of Wisconsin-Madison
| | - James Weger-Lucarelli
- Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University
| | - Thomas C. Friedrich
- Department of Pathobiological Sciences, University of Wisconsin-Madison
- Wisconsin National Primate Research Center, University of Wisconsin-Madison
| | - Matthew T. Aliota
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Twin Cities
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Marano JM, Weger-Lucarelli J. Replication in the presence of dengue convalescent serum impacts Zika virus neutralization sensitivity and fitness. Front Cell Infect Microbiol 2023; 13:1130749. [PMID: 36968111 PMCID: PMC10034770 DOI: 10.3389/fcimb.2023.1130749] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 02/13/2023] [Indexed: 03/11/2023] Open
Abstract
IntroductionFlaviviruses like dengue virus (DENV) and Zika virus (ZIKV) are mosquito-borne viruses that cause febrile, hemorrhagic, and neurological diseases in humans, resulting in 400 million infections annually. Due to their co-circulation in many parts of the world, flaviviruses must replicate in the presence of pre-existing adaptive immune responses targeted at serologically closely related pathogens, which can provide protection or enhance disease. However, the impact of pre-existing cross-reactive immunity as a driver of flavivirus evolution, and subsequently the implications on the emergence of immune escape variants, is poorly understood. Therefore, we investigated how replication in the presence of convalescent dengue serum drives ZIKV evolution.MethodsWe used an in vitro directed evolution system, passaging ZIKV in the presence of serum from humans previously infected with DENV (anti-DENV) or serum from DENV-naïve patients (control serum). Following five passages in the presence of serum, we performed next-generation sequencing to identify mutations that arose during passaging. We studied two non-synonymous mutations found in the anti-DENV passaged population (E-V355I and NS1-T139A) by generating individual ZIKV mutants and assessing fitness in mammalian cells and live mosquitoes, as well as their sensitivity to antibody neutralization.Results and discussionBoth viruses had increased fitness in Vero cells with and without the addition of anti-DENV serum and in human lung epithelial and monocyte cells. In Aedes aegypti mosquitoes—using blood meals with and without anti-DENV serum—the mutant viruses had significantly reduced fitness compared to wild-type ZIKV. These results align with the trade-off hypothesis of constrained mosquito-borne virus evolution. Notably, only the NS1-T139A mutation escaped neutralization, while E-V335I demonstrated enhanced neutralization sensitivity to neutralization by anti-DENV serum, indicating that neutralization escape is not necessary for viruses passaged under cross-reactive immune pressures. Future studies are needed to assess cross-reactive immune selection in humans and relevant animal models or with different flaviviruses.
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Affiliation(s)
- Jeffrey M. Marano
- Translational Biology, Medicine, and Health Graduate Program, Virginia Tech, Roanoke, VA, United States
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA, United States
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA, United States
| | - James Weger-Lucarelli
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA, United States
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA, United States
- *Correspondence: James Weger-Lucarelli,
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Frank DT, Byas AD, Murrieta R, Weger-Lucarelli J, Rückert C, Gallichotte E, Yoshimoto JA, Allen C, Bosco-Lauth AM, Graham B, Felix TA, Brault A, Ebel GD. Intracellular diversity of WNV within circulating avian peripheral blood mononuclear cells reveals host-dependent patterns of polyinfection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.27.525959. [PMID: 36747638 PMCID: PMC9900929 DOI: 10.1101/2023.01.27.525959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Error-prone replication of RNA viruses generates the genetic diversity required for adaptation within rapidly changing environments. Thus, arthropod-borne virus (arbovirus) populations exist in nature as mutant swarms that are maintained between arthropods and vertebrates. Previous studies have demonstrated that West Nile virus (WNV) population dynamics are host dependent: In American crows, which experience extremely high viremia, purifying selection is weak and population diversity is high compared to American robins, which have 100 to 1000-fold lower viremia. WNV passed in robins experiences fitness gains, whereas that passed in crows does not. Therefore, we tested the hypothesis that high crow viremia allows higher genetic diversity within individual avian peripheral-blood mononuclear cells (PBMCs), reasoning that this could have produced the previously observed host-specific differences in genetic diversity and fitness. Specifically, we infected cells and birds with a novel, barcoded version of WNV and sequenced viral RNA from single cells to quantify the number of WNV barcodes that each contained. Our results demonstrate that the richness of WNV populations within crows far exceeds that in robins. Similarly, rare WNV variants were maintained by crows more frequently than by robins. Our results suggest that increased viremia in crows relative to robins leads to maintenance of defective genomes and less prevalent variants, presumably through complementation. Our findings further suggest that weaker purifying selection in highly susceptible crows is attributable to this higher viremia, polyinfections and complementation. These studies further document the role of particular, ecologically relevant hosts in shaping virus population structure. Author Summary WNV mutational diversity in vertebrates is species-dependent. In crows, low frequency variants are common, and viral populations are more diverse. In robins, fewer mutations become permanent fixtures of the overall viral population. We infected crows, robins and a chicken cell line with a genetically marked (barcoded) WNV. Higher levels of virus led to multiple unique WNV genomes infecting individual cells, even when a genotype was present at low levels in the input viral stock. Our findings suggest that higher levels of circulating virus in natural hosts allow less fit viruses to survive in RNA virus populations through complementation by more fit viruses. This is significant as it allows less represented and less fit viruses to be maintained at low levels until they potentially emerge when virus environments change. Overall our data reveal new insights on the relationships between host susceptibility to high viremia and virus evolution.
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Affiliation(s)
- Dalit Talmi Frank
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Alex D. Byas
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Reyes Murrieta
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - James Weger-Lucarelli
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Claudia Rückert
- Department of Biochemistry and Molecular Biology, College of Agriculture, Biotechnology & Natural Resources, University of Nevada, Reno, Nevada, USA
| | - Emily Gallichotte
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Janna A. Yoshimoto
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Chris Allen
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Angela M. Bosco-Lauth
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Barbara Graham
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Todd A. Felix
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Golden, CO, USA
| | - Aaron Brault
- Division of Vector-borne Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention Fort Collins, Colorado, USA
| | - Gregory D. Ebel
- Center for Vector-borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
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10
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Rodríguez‐Pastor R, Shafran Y, Knossow N, Gutiérrez R, Harrus S, Zaman L, Lenski RE, Barrick JE, Hawlena H. A road map for in vivo evolution experiments with blood-borne parasitic microbes. Mol Ecol Resour 2022; 22:2843-2859. [PMID: 35599628 PMCID: PMC9796859 DOI: 10.1111/1755-0998.13649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 03/14/2022] [Accepted: 05/13/2022] [Indexed: 01/07/2023]
Abstract
Laboratory experiments in which blood-borne parasitic microbes evolve in their animal hosts offer an opportunity to study parasite evolution and adaptation in real time and under natural settings. The main challenge of these experiments is to establish a protocol that is both practical over multiple passages and accurately reflects natural transmission scenarios and mechanisms. We provide a guide to the steps that should be considered when designing such a protocol, and we demonstrate its use via a case study. We highlight the importance of choosing suitable ancestral genotypes, treatments, number of replicates per treatment, types of negative controls, dependent variables, covariates, and the timing of checkpoints for the experimental design. We also recommend specific preliminary experiments to determine effective methods for parasite quantification, transmission, and preservation. Although these methodological considerations are technical, they also often have conceptual implications. To this end, we encourage other researchers to design and conduct in vivo evolution experiments with blood-borne parasitic microbes, despite the challenges that the work entails.
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Affiliation(s)
- Ruth Rodríguez‐Pastor
- Jacob Blaustein Center for Scientific Cooperation, The Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
| | - Yarden Shafran
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, The Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
| | - Nadav Knossow
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, The Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
| | - Ricardo Gutiérrez
- Koret School of Veterinary Medicine, Faculty of Agricultural, Nutritional and Environmental SciencesThe Hebrew University of JerusalemRehovotIsrael
| | - Shimon Harrus
- Koret School of Veterinary Medicine, Faculty of Agricultural, Nutritional and Environmental SciencesThe Hebrew University of JerusalemRehovotIsrael
| | - Luis Zaman
- Department of Ecology and Evolutionary Biology, The Center for the Study of Complex Systems (CSCS)University of MichiganAnn ArborMichiganUSA
| | - Richard E. Lenski
- Department of Microbiology and Molecular GeneticsMichigan State UniversityEast LansingMichiganUSA
| | - Jeffrey E. Barrick
- Department of Molecular BiosciencesThe University of Texas AustinAustinTexasUSA
| | - Hadas Hawlena
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, The Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevMidreshet Ben‐GurionIsrael
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11
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Caldwell HS, Pata JD, Ciota AT. The Role of the Flavivirus Replicase in Viral Diversity and Adaptation. Viruses 2022; 14:1076. [PMID: 35632818 PMCID: PMC9143365 DOI: 10.3390/v14051076] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/03/2022] [Accepted: 05/06/2022] [Indexed: 02/04/2023] Open
Abstract
Flaviviruses include several emerging and re-emerging arboviruses which cause millions of infections each year. Although relatively well-studied, much remains unknown regarding the mechanisms and means by which these viruses readily alternate and adapt to different hosts and environments. Here, we review a subset of the different aspects of flaviviral biology which impact host switching and viral fitness. These include the mechanism of replication and structural biology of the NS3 and NS5 proteins, which reproduce the viral genome; rates of mutation resulting from this replication and the role of mutational frequency in viral fitness; and the theory of quasispecies evolution and how it contributes to our understanding of genetic and phenotypic plasticity.
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Affiliation(s)
- Haley S. Caldwell
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA;
- Department of Biomedical Sciences, State University of New York at Albany, School of Public Health, Rensselaer, NY 12144, USA;
| | - Janice D. Pata
- Department of Biomedical Sciences, State University of New York at Albany, School of Public Health, Rensselaer, NY 12144, USA;
- Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA
| | - Alexander T. Ciota
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA;
- Department of Biomedical Sciences, State University of New York at Albany, School of Public Health, Rensselaer, NY 12144, USA;
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12
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Murrieta RA, Garcia-Luna SM, Murrieta DJ, Halladay G, Young MC, Fauver JR, Gendernalik A, Weger-Lucarelli J, Rückert C, Ebel GD. Impact of extrinsic incubation temperature on natural selection during Zika virus infection of Aedes aegypti and Aedes albopictus. PLoS Pathog 2021; 17:e1009433. [PMID: 34752502 PMCID: PMC8629396 DOI: 10.1371/journal.ppat.1009433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 11/29/2021] [Accepted: 10/18/2021] [Indexed: 01/10/2023] Open
Abstract
Arthropod-borne viruses (arboviruses) require replication across a wide range of temperatures to perpetuate. While vertebrate hosts tend to maintain temperatures of approximately 37°C—40°C, arthropods are subject to ambient temperatures which can have a daily fluctuation of > 10°C. Temperatures impact vector competence, extrinsic incubation period, and mosquito survival unimodally, with optimal conditions occurring at some intermediate temperature. In addition, the mean and range of daily temperature fluctuations influence arbovirus perpetuation and vector competence. The impact of temperature on arbovirus genetic diversity during systemic mosquito infection, however, is poorly understood. Therefore, we determined how constant extrinsic incubation temperatures of 25°C, 28°C, 32°C, and 35°C control Zika virus (ZIKV) vector competence and population dynamics within Aedes aegypti and Aedes albopictus mosquitoes. We also examined fluctuating temperatures which better mimic field conditions in the tropics. We found that vector competence varied in a unimodal manner for constant temperatures peaking between 28°C and 32°C for both Aedes species. Transmission peaked at 10 days post-infection for Aedes aegypti and 14 days for Aedes albopictus. Conversely, fluctuating temperature decreased vector competence. Using RNA-seq to characterize ZIKV population structure, we identified that temperature alters the selective environment in unexpected ways. During mosquito infection, constant temperatures more often elicited positive selection whereas fluctuating temperatures led to strong purifying selection in both Aedes species. These findings demonstrate that temperature has multiple impacts on ZIKV biology, including major effects on the selective environment within mosquitoes. Arthropod-borne viruses (arboviruses) have emerged in recent decades due to complex factors that include increases in international travel and trade, the breakdown of public health infrastructure, land use changes, and many others. Climate change also has the potential to shift the geographical ranges of arthropod vectors, consequently increasing the global risk of arbovirus infection. Changing temperatures may alter the virus-host interaction, ultimately resulting in the emergence of new viruses and virus genotypes in new areas. Therefore, we sought to characterize how temperature (both constant and fluctuating) alters the ability of Aedes aegypti and Aedes albopictus to transmit Zika virus, and how it influences virus populations within mosquitoes. We found that intermediate temperatures maximize virus transmission compared to more extreme and fluctuating temperatures. Constant temperatures increased positive selection on virus genomes, while fluctuating temperatures strengthened purifying selection. Our studies provide evidence that in addition to altering vector competence, temperature significantly influences natural selection within mosquitoes.
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Affiliation(s)
- Reyes A. Murrieta
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Selene M. Garcia-Luna
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- Department of Entomology, Texas A&M University, College Station, Texas, United States of America
| | - Deedra J. Murrieta
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Gareth Halladay
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Michael C. Young
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Joseph R. Fauver
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- Yale School of Public Health, Department of Epidemiology of Microbial Diseases, Laboratory of Epidemiology of Public Health, New Haven, Connecticut, United States of America
| | - Alex Gendernalik
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - James Weger-Lucarelli
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- Department of Biomedical Sciences & Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Claudia Rückert
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- Department of Biochemistry and Molecular Biology, College of Agriculture, Biotechnology & Natural Resources, University of Nevada, Reno, Nevada, United States of America
| | - Gregory D. Ebel
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- * E-mail:
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13
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Saxenhofer M, Labutin A, White TA, Heckel G. Host genetic factors associated with the range limit of a European hantavirus. Mol Ecol 2021; 31:252-265. [PMID: 34614264 PMCID: PMC9298007 DOI: 10.1111/mec.16211] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/30/2021] [Accepted: 09/22/2021] [Indexed: 11/30/2022]
Abstract
The natural host ranges of many viruses are restricted to very specific taxa. Little is known about the molecular barriers between species that lead to the establishment of this restriction or generally prevent virus emergence in new hosts. Here, we identify genomic polymorphisms in a natural rodent host associated with a strong genetic barrier to the transmission of European Tula orthohantavirus (TULV). We analysed the very abrupt spatial transition between two major phylogenetic clades in TULV across the comparatively much wider natural hybrid zone between evolutionary lineages of their reservoir host, the common vole (Microtus arvalis). Genomic scans of 79,225 single nucleotide polymorphisms (SNPs) in 323 TULV‐infected host individuals detected 30 SNPs that were consistently associated with the TULV clades CEN.S or EST.S in two replicate sampling transects. Focusing the analysis on 199 voles with evidence of genomic admixture at the individual level (0.1–0.9) supported statistical significance for all 30 loci. Host genomic variation at these SNPs explained up to 37.6% of clade‐specific TULV infections. Genes in the vicinity of associated SNPs include SAHH, ITCH and two members of the Syngr gene family, which are involved in functions related to immune response or membrane transport. This study demonstrates the relevance of natural hybrid zones as systems not only for studying processes of evolutionary divergence and speciation, but also for the detection of evolving genetic barriers for specialized parasites.
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Affiliation(s)
- Moritz Saxenhofer
- Institute of Ecology and Evolution, University of Bern, Bern, Switzerland.,Swiss Institute of Bioinformatics, Quartier Sorge - Bâtiment Génopode, Lausanne, Switzerland
| | - Anton Labutin
- Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Thomas A White
- Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Gerald Heckel
- Institute of Ecology and Evolution, University of Bern, Bern, Switzerland.,Swiss Institute of Bioinformatics, Quartier Sorge - Bâtiment Génopode, Lausanne, Switzerland
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14
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Fay RL, Ngo KA, Kuo L, Willsey GG, Kramer LD, Ciota AT. Experimental Evolution of West Nile Virus at Higher Temperatures Facilitates Broad Adaptation and Increased Genetic Diversity. Viruses 2021; 13:1889. [PMID: 34696323 PMCID: PMC8540194 DOI: 10.3390/v13101889] [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: 07/21/2021] [Revised: 09/14/2021] [Accepted: 09/16/2021] [Indexed: 11/18/2022] Open
Abstract
West Nile virus (WNV, Flaviviridae, Flavivirus) is a mosquito-borne flavivirus introduced to North America in 1999. Since 1999, the Earth's average temperature has increased by 0.6 °C. Mosquitoes are ectothermic organisms, reliant on environmental heat sources. Temperature impacts vector-virus interactions which directly influence arbovirus transmission. RNA viral replication is highly error-prone and increasing temperature could further increase replication rates, mutation frequencies, and evolutionary rates. The impact of temperature on arbovirus evolutionary trajectories and fitness landscapes has yet to be sufficiently studied. To investigate how temperature impacts the rate and extent of WNV evolution in mosquito cells, WNV was experimentally passaged 12 times in Culex tarsalis cells, at 25 °C and 30 °C. Full-genome deep sequencing was used to compare genetic signatures during passage, and replicative fitness was evaluated before and after passage at each temperature. Our results suggest adaptive potential at both temperatures, with unique temperature-dependent and lineage-specific genetic signatures. Further, higher temperature passage was associated with significantly increased replicative fitness at both temperatures and increases in nonsynonymous mutations. Together, these data indicate that if similar selective pressures exist in natural systems, increases in temperature could accelerate emergence of high-fitness strains with greater phenotypic plasticity.
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Affiliation(s)
- Rachel L. Fay
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Rensselaer, NY 12144, USA; (R.L.F.); (L.D.K.)
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA; (K.A.N.); (L.K.)
| | - Kiet A. Ngo
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA; (K.A.N.); (L.K.)
| | - Lili Kuo
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA; (K.A.N.); (L.K.)
| | - Graham G. Willsey
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA;
| | - Laura D. Kramer
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Rensselaer, NY 12144, USA; (R.L.F.); (L.D.K.)
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA; (K.A.N.); (L.K.)
| | - Alexander T. Ciota
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Rensselaer, NY 12144, USA; (R.L.F.); (L.D.K.)
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY 12159, USA; (K.A.N.); (L.K.)
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15
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Butković A, González R, Rivarez MPS, Elena SF. A genome-wide association study identifies Arabidopsis thaliana genes that contribute to differences in the outcome of infection with two Turnip mosaic potyvirus strains that differ in their evolutionary history and degree of host specialization. Virus Evol 2021; 7:veab063. [PMID: 34532063 PMCID: PMC8438913 DOI: 10.1093/ve/veab063] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/23/2021] [Accepted: 06/30/2021] [Indexed: 01/14/2023] Open
Abstract
Viruses lie in a continuum between generalism and specialism depending on their ability to infect more or less hosts. While generalists are able to successfully infect a wide variety of hosts, specialists are limited to one or a few. Even though generalists seem to gain an advantage due to their wide host range, they usually pay a pleiotropic fitness cost within each host. On the contrary, a specialist has maximal fitness within its own host. A relevant yet poorly explored question is whether viruses differ in the way they interact with their hosts' gene expression depending on their degree of specialization. Using a genome-wide association study approach, we have identified host genes whose expression depends on whether hosts were infected with more or less specialized viral strains. Four hundred fifty natural accessions of Arabidopsis thaliana were inoculated with Turnip mosaic potyvirus strains with different past evolutionary histories and that shown different degrees of specialization. Three disease-related traits were measured and associated with different sets of host genes for each strain. The genetic architectures of these traits differed among viral strains and, in the case of the more specialized virus, also varied along the duration of infection. While most of the mapped loci were strain specific, one shared locus was mapped for both strains, a disease-resistance TIR-NBS-LRR class protein. Likewise, only putative cysteine-rich receptor-like protein kinases were involved in all three traits. The impact on disease progress of 10 selected genes was validated by studying the infection phenotypes of loss-of-function mutant plants. Nine of these mutants have altered the disease progress and/or symptoms intensity between both strains. Compared to wild-type plants six had an effect on both viral strains, three had an effect only on the more specialized, and two were significant during infection with the less specialized.
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16
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Singhal S, Turner PE. Effects of historical co-infection on host shift abilities of exploitative and competitive viruses. Evolution 2021; 75:1878-1888. [PMID: 33969482 DOI: 10.1111/evo.14263] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 04/03/2021] [Accepted: 04/16/2021] [Indexed: 12/29/2022]
Abstract
Rapid evolution contributes to frequent emergence of RNA viral pathogens on novel hosts. However, accurately predicting which viral genotypes will emerge has been elusive. Prior work with lytic RNA bacteriophage ɸ6 (family Cystoviridae) suggested that evolution under low multiplicity of infection (MOI; proportion of viruses to susceptible cells) selected for greater host exploitation, while evolution under high MOI selected for better intracellular competition against co-infecting viruses. We predicted that phage genotypes that had experienced 300 generations of low MOI ecological history would be relatively advantaged in initial growth on two novel hosts. We inferred viral growth through changes in host population density, specifically by analyzing five attributes of growth curves of infected bacteria. Despite equivalent growth of evolved viruses on the original host, low MOI evolved clones were generally advantaged relative to high MOI clones in exploiting novel hosts. However, the specific attributes of growth curves that supported their advantage differed by host, indicating interactions between both viral and host genotype. Although there will be host specificity in viral growth, we suggest based on infectivity differences of viruses from high versus low MOI histories that prior MOI selection can later affect emergence potential.
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Affiliation(s)
- Sonia Singhal
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, 06520, USA.,BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, Michigan, 48824, USA.,Current affiliation: Department of Biological Sciences, San José Sate University, San José, California, 95192, USA
| | - Paul E Turner
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, 06520, USA.,BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, Michigan, 48824, USA.,Graduate Program in Microbiology, Yale School of Medicine, New Haven, Connecticut, 06520, USA
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17
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Mechanisms Underlying Host Range Variation in Flavivirus: From Empirical Knowledge to Predictive Models. J Mol Evol 2021; 89:329-340. [PMID: 34059925 DOI: 10.1007/s00239-021-10013-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 05/13/2021] [Indexed: 12/22/2022]
Abstract
Preventing and controlling epidemics caused by vector-borne viruses are particularly challenging due to their diverse pool of hosts and highly adaptive nature. Many vector-borne viruses belong to the Flavivirus genus, whose members vary greatly in host range and specificity. Members of the Flavivirus genus can be categorized to four main groups: insect-specific viruses that are maintained solely in arthropod populations, mosquito-borne viruses and tick-borne viruses that are transmitted to vertebrate hosts by mosquitoes or ticks via blood feeding, and those with no-known vector. The mosquito-borne group encompasses the yellow fever, dengue, and West Nile viruses, all of which are globally spread and cause severe morbidity in humans. The Flavivirus genus is genetically diverse, and its members are subject to different host-specific and vector-specific selective constraints, which do not always align. Thus, understanding the underlying genetic differences that led to the diversity in host range within this genus is an important aspect in deciphering the mechanisms that drive host compatibility and can aid in the constant arms-race against viral threats. Here, we review the phylogenetic relationships between members of the genus, their infection bottlenecks, and phenotypic and genomic differences. We further discuss methods that utilize these differences for prediction of host shifts in flaviviruses and can contribute to viral surveillance efforts.
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18
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Talavera-Aguilar LG, Murrieta RA, Kiem S, Cetina-Trejo RC, Baak-Baak CM, Ebel GD, Blitvich BJ, Machain-Williams C. Infection, dissemination, and transmission efficiencies of Zika virus in Aedes aegypti after serial passage in mosquito or mammalian cell lines or alternating passage in both cell types. Parasit Vectors 2021; 14:261. [PMID: 34006306 PMCID: PMC8130322 DOI: 10.1186/s13071-021-04726-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/16/2021] [Indexed: 11/10/2022] Open
Abstract
Background Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) with an urban transmission cycle that primarily involves humans and Aedes aegypti. Evidence suggests that the evolution of some arboviruses is constrained by their dependency on alternating between disparate (vertebrate and invertebrate) hosts. The goals of this study are to compare the genetic changes that occur in ZIKV after serial passaging in mosquito or vertebrate cell lines or alternate passaging in both cell types and to compare the replication, dissemination, and transmission efficiencies of the cell culture-derived viruses in Ae. aegypti. Methods An isolate of ZIKV originally acquired from a febrile patient in Yucatan, Mexico, was serially passaged six times in African green monkey kidney (Vero) cells or Aedes albopictus (C6/36) cells or both cell types by alternating passage. A colony of Ae. aegypti from Yucatan was established, and mosquitoes were challenged with the cell-adapted viruses. Midguts, Malpighian tubules, ovaries, salivary glands, wings/legs and saliva were collected at various times after challenge and tested for evidence of virus infection. Results Genome sequencing revealed the presence of two non-synonymous substitutions in the premembrane and NS1 regions of the mosquito cell-adapted virus and two non-synonymous substitutions in the capsid and NS2A regions of both the vertebrate cell-adapted and alternate-passaged viruses. Additional genetic changes were identified by intrahost variant frequency analysis. Virus maintained by continuous C6/36 cell passage was significantly more infectious in Ae. aegypti than viruses maintained by alternating passage and consecutive Vero cell passage. Conclusions Mosquito cell-adapted ZIKV displayed greater in vivo fitness in Ae. aegypti compared to the other viruses, indicating that obligate cycling between disparate hosts carries a fitness cost. These data increase our understanding of the factors that drive ZIKV adaptation and evolution and underscore the important need to consider the in vivo passage histories of flaviviruses to be evaluated in vector competence studies. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04726-1.
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Affiliation(s)
- Lourdes G Talavera-Aguilar
- Laboratorio de Arbovirología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, México
| | - Reyes A Murrieta
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Sungmin Kiem
- Department of Infectious Diseases in Internal Medicine, Sejong Chungnam National University Hospital, School of Medicine, Chungnam National University, Sejong, Korea
| | - Rosa C Cetina-Trejo
- Laboratorio de Arbovirología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, México
| | - Carlos M Baak-Baak
- Laboratorio de Arbovirología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, México
| | - Gregory D Ebel
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Bradley J Blitvich
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Carlos Machain-Williams
- Laboratorio de Arbovirología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, México.
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19
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Pontremoli C, Forni D, Clerici M, Cagliani R, Sironi M. Alternation between taxonomically divergent hosts is not the major determinant of flavivirus evolution. Virus Evol 2021; 7:veab040. [PMID: 33976907 PMCID: PMC8093920 DOI: 10.1093/ve/veab040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Flaviviruses display diverse epidemiological and ecological features. Tick-borne and mosquito-borne flaviviruses (TBFV and MBFV, respectively) are important human pathogens that alternate replication in invertebrate vectors and vertebrate hosts. The Flavivirus genus also includes insect-specific viruses (ISFVs) and viruses with unknown invertebrate hosts. It is generally accepted that viruses that alternate between taxonomically different hosts evolve slowly and that the evolution of MBFVs and TBFVs is dominated by strong constraints, with limited episodes of positive selection. We exploited the availability of flavivirus genomes to test these hypotheses and to compare their rates and patterns of evolution. We estimated the substitution rates of CFAV and CxFV (two ISFVs) and, by taking into account the time-frame of measurement, compared them with those of other flaviviruses. Results indicated that CFAV and CxFV display relatively different substitution rates. However, these data, together with estimates for single-host members of the Flaviviridae family, indicated that MBFVs do not display relatively slower evolution. Conversely, TBFVs displayed some of lowest substitution rates among flaviviruses. Analysis of selective patterns over longer evolutionary time-frames confirmed that MBFVs evolve under strong purifying selection. Interestingly, TBFVs and ISFVs did not show extremely different levels of constraint, although TBFVs alternate among hosts, whereas ISFVs do not. Additional results showed that episodic positive selection drove the evolution of MBFVs, despite their high constraint. Positive selection was also detected on two branches of the TBFVs phylogeny that define the seabird clade. Thus, positive selection was much more common during the evolution of arthropod-borne flaviviruses than previously thought. Overall, our data indicate that flavivirus evolutionary patterns are complex and most likely determined by multiple factors, not limited to the alternation between taxonomically divergent hosts. The frequency of both positive and purifying selection, especially in MBFVs, suggests that a minority of sites in the viral polyprotein experience weak constraint and can evolve to generate new viral phenotypes and possibly promote adaptation to new hosts.
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Affiliation(s)
| | - Diego Forni
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini 23842, Italy
| | - Mario Clerici
- Department of Physiopathology and Transplantation, University of Milan, Milan 20122, Italy,Don C. Gnocchi Foundation ONLUS, IRCCS, Milan 20121, Italy
| | - Rachele Cagliani
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini 23842, Italy
| | - Manuela Sironi
- Scientific Institute IRCCS E. MEDEA, Bioinformatics, Bosisio Parini 23842, Italy
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20
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Abstract
Zika virus (ZIKV) has the unusual capacity to circumvent natural alternating mosquito-human transmission and be directly transmitted human-to-human via sexual and vertical routes. The impact of direct transmission on ZIKV evolution and adaptation to vertebrate hosts is unknown. Here we show that molecularly barcoded ZIKV rapidly adapted to a mammalian host during direct transmission chains in mice, coincident with the emergence of an amino acid substitution previously shown to enhance virulence. In contrast, little to no adaptation of ZIKV to mice was observed following chains of direct transmission in mosquitoes or alternating host transmission. Detailed genetic analyses revealed that ZIKV evolution in mice was generally more convergent and subjected to more relaxed purifying selection than in mosquitoes or alternate passages. These findings suggest that prevention of direct human transmission chains may be paramount to resist gains in ZIKV virulence.Importance We used experimental evolution to model chains of direct and indirect Zika virus (ZIKV) transmission by serially passaging a synthetic swarm of molecularly barcoded ZIKV within and between mosquitoes and mice. We observed that direct mouse transmission chains facilitated a rapid increase in ZIKV replication and enhanced virulence in mice. These findings demonstrate that ZIKV is capable of rapid adaptation to a vertebrate host and indicate that direct human-to-human transmission could pose a greater threat to public health than currently realized.
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21
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Scroggs SLP, Gass JT, Chinnasamy R, Widen SG, Azar SR, Rossi SL, Arterburn JB, Vasilakis N, Hanley KA. Evolution of resistance to fluoroquinolones by dengue virus serotype 4 provides insight into mechanism of action and consequences for viral fitness. Virology 2021; 552:94-106. [PMID: 33120225 PMCID: PMC7528753 DOI: 10.1016/j.virol.2020.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 08/30/2020] [Accepted: 09/08/2020] [Indexed: 02/07/2023]
Abstract
Drugs against flaviviruses such as dengue (DENV) and Zika (ZIKV) virus are urgently needed. We previously demonstrated that three fluoroquinolones, ciprofloxacin, enoxacin, and difloxacin, suppress replication of six flaviviruses. To investigate the barrier to resistance and mechanism(s) of action of these drugs, DENV-4 was passaged in triplicate in HEK-293 cells in the presence or absence of each drug. Resistance to ciprofloxacin was detected by the seventh passage and to difloxacin by the tenth, whereas resistance to enoxacin did not occur within ten passages. Two putative resistance-conferring mutations were detected in the envelope gene of ciprofloxacin and difloxacin-resistant DENV-4. In the absence of ciprofloxacin, ciprofloxacin-resistant viruses sustained a significantly higher viral titer than control viruses in HEK-293 and HuH-7 cells and resistant viruses were more stable than control viruses at 37 °C. These results suggest that the mechanism of action of ciprofloxacin and difloxacin involves interference with virus binding or entry.
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Affiliation(s)
- Stacey L P Scroggs
- Department of Biology, New Mexico State University, Las Cruces, NM, USA.
| | - Jordan T Gass
- Department of Biology, New Mexico State University, Las Cruces, NM, USA
| | - Ramesh Chinnasamy
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM, USA
| | - Steven G Widen
- Department of Biochemistry & Molecular Biology, The University of Texas Medical Branch, Galveston, TX, USA
| | - Sasha R Azar
- Department of Pathology, The University of University of Texas Medical Branch, Galveston, TX, USA
| | - Shannan L Rossi
- Department of Pathology, The University of University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, The University of University of Texas Medical Branch, Galveston, TX, USA
| | - Jeffrey B Arterburn
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM, USA
| | - Nikos Vasilakis
- Department of Pathology, The University of University of Texas Medical Branch, Galveston, TX, USA; Center for Biodefense and Emerging Infectious Diseases, The University of University of Texas Medical Branch, Galveston, TX, USA; Center for Tropical Diseases, The University of University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, The University of University of Texas Medical Branch, Galveston, TX, USA
| | - Kathryn A Hanley
- Department of Biology, New Mexico State University, Las Cruces, NM, USA
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22
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Population bottlenecks and founder effects: implications for mosquito-borne arboviral emergence. Nat Rev Microbiol 2021; 19:184-195. [PMID: 33432235 PMCID: PMC7798019 DOI: 10.1038/s41579-020-00482-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2020] [Indexed: 01/31/2023]
Abstract
Transmission of arthropod-borne viruses (arboviruses) involves infection and replication in both arthropod vectors and vertebrate hosts. Nearly all arboviruses are RNA viruses with high mutation frequencies, which leaves them vulnerable to genetic drift and fitness losses owing to population bottlenecks during vector infection, dissemination from the midgut to the salivary glands and transmission to the vertebrate host. However, despite these bottlenecks, they seem to avoid fitness declines that can result from Muller's ratchet. In addition, founder effects that occur during the geographic introductions of human-amplified arboviruses, including chikungunya virus and Zika virus, can affect epidemic and endemic circulation, as well as virulence. In this Review, we discuss the role of genetic drift following population bottlenecks and founder effects in arboviral evolution and spread, and the emergence of human disease.
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23
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Divergent Mutational Landscapes of Consensus and Minority Genotypes of West Nile Virus Demonstrate Host and Gene-Specific Evolutionary Pressures. Genes (Basel) 2020; 11:genes11111299. [PMID: 33143358 PMCID: PMC7692055 DOI: 10.3390/genes11111299] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/19/2020] [Accepted: 10/29/2020] [Indexed: 01/12/2023] Open
Abstract
Our current understanding of the natural evolution of RNA viruses comes largely from consensus level genetic analyses which ignore the diverse mutant swarms that comprise within-host viral populations. The breadth and composition of viral mutant swarms impact viral fitness and adaptation, and the capacity for swarm plasticity is likely to be particularly important for arthropod-borne viruses (arboviruses) that cycle between taxonomically divergent hosts. Despite this, characterization of the relationship between the selective pressures and genetic signatures of the mutant swarm and consensus sequences is lacking. To clarify this, we analyzed previously generated whole genome, deep-sequencing data from 548 West Nile virus samples isolated from avian tissues or mosquitoes in New York State from 1999-2018. Both consensus level (interhost) and minority level (intrahost) nucleotide and amino acid sequences were analyzed, and diversity at each position was calculated across the genome in order to assess the relationship between minority and consensus sequences for individual genes and hosts. Our results indicate that consensus sequences are an inept representation of the overall genetic diversity. Unique host and gene-specific signatures and selective pressures were identified. These data demonstrate that an accurate and comprehensive understanding of arbovirus evolution and adaptation within and between hosts requires consideration of minority genotypes.
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24
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Lievens EJP, Michalakis Y, Lenormand T. Trait‐specific trade‐offs prevent niche expansion in two parasites. J Evol Biol 2020; 33:1704-1714. [DOI: 10.1111/jeb.13708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 09/08/2020] [Accepted: 09/10/2020] [Indexed: 12/31/2022]
Affiliation(s)
- Eva J. P. Lievens
- CEFE, CNRS Univ MontpellierUniv Paul Valéry Montpellier 3EPHEIRD Montpellier France
- UMR 5290 MIVEGEC Univ MontpellierCNRSIRD Montpellier Cedex 5 France
| | - Yannis Michalakis
- UMR 5290 MIVEGEC Univ MontpellierCNRSIRD Montpellier Cedex 5 France
- Centre of Research in Ecology and Evolution of Diseases (CREES) Montpellier France
| | - Thomas Lenormand
- CEFE, CNRS Univ MontpellierUniv Paul Valéry Montpellier 3EPHEIRD Montpellier France
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25
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Bellone R, Failloux AB. The Role of Temperature in Shaping Mosquito-Borne Viruses Transmission. Front Microbiol 2020; 11:584846. [PMID: 33101259 PMCID: PMC7545027 DOI: 10.3389/fmicb.2020.584846] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Accepted: 09/07/2020] [Indexed: 12/28/2022] Open
Abstract
Mosquito-borne diseases having the greatest impact on human health are typically prevalent in the tropical belt of the world. However, these diseases are conquering temperate regions, raising the question of the role of temperature on their dynamics and expansion. Temperature is one of the most significant abiotic factors affecting, in many ways, insect vectors and the pathogens they transmit. Here, we debate the veracity of this claim by synthesizing current knowledge on the effects of temperature on arboviruses and their vectors, as well as the outcome of their interactions.
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Affiliation(s)
- Rachel Bellone
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
- Sorbonne Université, Collège Doctoral, Paris, France
| | - Anna-Bella Failloux
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
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26
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The Genetic Diversification of a Single Bluetongue Virus Strain Using an In Vitro Model of Alternating-Host Transmission. Viruses 2020; 12:v12091038. [PMID: 32961886 PMCID: PMC7551957 DOI: 10.3390/v12091038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/31/2020] [Accepted: 09/15/2020] [Indexed: 12/16/2022] Open
Abstract
Bluetongue virus (BTV) is an arbovirus that has been associated with dramatic epizootics in both wild and domestic ruminants in recent decades. As a segmented, double-stranded RNA virus, BTV can evolve via several mechanisms due to its genomic structure. However, the effect of BTV’s alternating-host transmission cycle on the virus’s genetic diversification remains poorly understood. Whole genome sequencing approaches offer a platform for investigating the effect of host-alternation across all ten segments of BTV’s genome. To understand the role of alternating hosts in BTV’s genetic diversification, a field isolate was passaged under three different conditions: (i) serial passages in Culicoides sonorensis cells, (ii) serial passages in bovine pulmonary artery endothelial cells, or (iii) alternating passages between insect and bovine cells. Aliquots of virus were sequenced, and single nucleotide variants were identified. Measures of viral population genetics were used to quantify the genetic diversification that occurred. Two consensus variants in segments 5 and 10 occurred in virus from all three conditions. While variants arose across all passages, measures of genetic diversity remained largely similar across cell culture conditions. Despite passage in a relaxed in vitro system, we found that this BTV isolate exhibited genetic stability across passages and conditions. Our findings underscore the valuable role that whole genome sequencing may play in improving understanding of viral evolution and highlight the genetic stability of BTV.
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27
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Ko HY, Salem GM, Chang GJJ, Chao DY. Application of Next-Generation Sequencing to Reveal How Evolutionary Dynamics of Viral Population Shape Dengue Epidemiology. Front Microbiol 2020; 11:1371. [PMID: 32636827 PMCID: PMC7318875 DOI: 10.3389/fmicb.2020.01371] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 05/27/2020] [Indexed: 12/13/2022] Open
Abstract
Dengue viral (DENV) infection results in a wide spectrum of clinical manifestations from asymptomatic, mild fever to severe hemorrhage diseases upon infection. Severe dengue is the leading cause of pediatric deaths and/or hospitalizations, which are a major public health burden in dengue-endemic or hyperendemic countries. Like other RNA viruses, DENV continues to evolve. Adaptive mutations are obscured by the major consensus sequence (so-called wild-type sequences) and can only be identified once they become the dominant viruses in the virus population, a process that can take months or years. Traditional surveillance systems still rely on Sanger consensus sequencing. However, with the recent advancement of high-throughput next-generation sequencing (NGS) technologies, the genome-wide investigation of virus population within-host and between-hosts becomes achievable. Thus, viral population sequencing by NGS can increase our understanding of the changing epidemiology and evolution of viral genomics at the molecular level. This review focuses on the studies within the recent decade utilizing NGS in different experimental and epidemiological settings to understand how the adaptive evolution of dengue variants shapes the dengue epidemic and disease severity through its transmission. We propose three types of studies that can be pursued in the future to enhance our surveillance for epidemic prediction and better medical management.
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Affiliation(s)
- Hui-Ying Ko
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan
| | - Gielenny M Salem
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan
| | - Gwong-Jen J Chang
- Arboviral Diseases Branch, Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, United States
| | - Day-Yu Chao
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan
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28
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Nurtay A, Hennessy MG, Alsedà L, Elena SF, Sardanyés J. Host-virus evolutionary dynamics with specialist and generalist infection strategies: Bifurcations, bistability, and chaos. CHAOS (WOODBURY, N.Y.) 2020; 30:053128. [PMID: 32491911 DOI: 10.1063/1.5144875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/16/2020] [Indexed: 06/11/2023]
Abstract
In this work, we have investigated the evolutionary dynamics of a generalist pathogen, e.g., a virus population, that evolves toward specialization in an environment with multiple host types. We have particularly explored under which conditions generalist viral strains may rise in frequency and coexist with specialist strains or even dominate the population. By means of a nonlinear mathematical model and bifurcation analysis, we have determined the theoretical conditions for stability of nine identified equilibria and provided biological interpretation in terms of the infection rates for the viral specialist and generalist strains. By means of a stability diagram, we identified stable fixed points and stable periodic orbits, as well as regions of bistability. For arbitrary biologically feasible initial population sizes, the probability of evolving toward stable solutions is obtained for each point of the analyzed parameter space. This probability map shows combinations of infection rates of the generalist and specialist strains that might lead to equal chances for each type becoming the dominant strategy. Furthermore, we have identified infection rates for which the model predicts the onset of chaotic dynamics. Several degenerate Bogdanov-Takens and zero-Hopf bifurcations are detected along with generalized Hopf and zero-Hopf bifurcations. This manuscript provides additional insights into the dynamical complexity of host-pathogen evolution toward different infection strategies.
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Affiliation(s)
- Anel Nurtay
- Centre de Recerca Matemàtica (CRM), Campus de Bellaterra, Edifici C, 08193 Bellaterra, Spain
| | - Matthew G Hennessy
- Centre de Recerca Matemàtica (CRM), Campus de Bellaterra, Edifici C, 08193 Bellaterra, Spain
| | - Lluís Alsedà
- Centre de Recerca Matemàtica (CRM), Campus de Bellaterra, Edifici C, 08193 Bellaterra, Spain
| | - Santiago F Elena
- Instituto de Biología Integrativa de Sistemas (I2SysBio), CSIC-Universitat de València, Parc Científic UV, Paterna 46980 València, Spain
| | - Josep Sardanyés
- Centre de Recerca Matemàtica (CRM), Campus de Bellaterra, Edifici C, 08193 Bellaterra, Spain
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29
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Caldwell HS, Ngo K, Pata JD, Kramer LD, Ciota AT. West Nile Virus fidelity modulates the capacity for host cycling and adaptation. J Gen Virol 2020; 101:410-419. [PMID: 32068528 DOI: 10.1099/jgv.0.001393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The fidelity of flaviviruses is thought to be tightly regulated for optimal fitness within and between hosts. West Nile virus (WNV) high-fidelity (HiFi) mutations V793I and G806R within the RNA-dependent RNA polymerase, and low-fidelity (LoFi) mutation T248I within the methyltransferase, were previously shown to attenuate infectivity and replicative fitness in Culex mosquitoes and Culex tarsalis (CXT) cells but not in mammalian cells. We hypothesized that fidelity alterations would modify adaptation and maintenance in a host-specific manner. To test this hypothesis, wild-type (WT), HiFi (V793I/G806R) and LoFi (T248I) variants were sequentially passaged eight times in avian (PDE) or mosquito cells, or alternately between the two. Initial characterization confirmed that fidelity mutants are attenuated in mosquito, but not avian, cells. Deep sequencing revealed mutations unique to both cell lines and fidelity mutants, including ENV G1378A, a mutation associated with avian cell adaptation. To characterize maintenance and adaptation, viral outputs were monitored throughout passaging and viral fitness was assessed. The results indicate that fidelity mutants can at times recover fitness during mosquito cell passage, but remain attenuated relative to WT. Despite similar initial fitness, LoFi mutants were impaired during sequential passage in avian cells. Conversely, HiFi mutants passaged in avian cells showed increased adaptation, suggesting that increased fidelity may be advantageous in avian hosts. Although some adaptation occurred with individual mutants, the output titres of fidelity mutants were on average lower and were often lost during host switching. These data confirm that arbovirus fidelity is likely fine-tuned to maximize survival in disparate hosts.
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Affiliation(s)
- Haley S Caldwell
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY, USA.,Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, NY, USA
| | - Kiet Ngo
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY, USA
| | - Janice D Pata
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, NY, USA
| | - Laura D Kramer
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY, USA.,Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, NY, USA
| | - Alexander T Ciota
- The Arbovirus Laboratory, Wadsworth Center, New York State Department of Health, Slingerlands, NY, USA.,Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, NY, USA
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30
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Sinigaglia A, Peta E, Riccetti S, Barzon L. New avenues for therapeutic discovery against West Nile virus. Expert Opin Drug Discov 2020; 15:333-348. [DOI: 10.1080/17460441.2020.1714586] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Elektra Peta
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Silvia Riccetti
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Luisa Barzon
- Department of Molecular Medicine, University of Padova, Padova, Italy
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31
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Camp JV, Nowotny N. The knowns and unknowns of West Nile virus in Europe: what did we learn from the 2018 outbreak? Expert Rev Anti Infect Ther 2020; 18:145-154. [PMID: 31914833 DOI: 10.1080/14787210.2020.1713751] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Introduction: West Nile virus (WNV) is a mosquito-borne human and animal pathogen with nearly worldwide distribution. In Europe, the virus is endemic with seasonal regional outbreaks that have increased in frequency over the last 10 years. A massive outbreak occurred across southern and central Europe in 2018 with the number of confirmed human cases increasing up to 7.2-fold from the previous year, and expanding to include previously virus-free regions.Areas covered: This review focuses on potential causes that may explain the 2018 European WNV outbreak. We discuss the role genetic, ecological, and environmental aspects may have played in the increased activity during the 2018 transmission season, summarizing the latest epidemiological and virological publications.Expert opinion: Optimal environmental conditions, specifically increased temperature, were most likely responsible for the observed outbreak. Other factors cannot be ruled out due to limited available information, including factors that may influence host/vector abundance and contact. Europe will likely experience even larger-scale outbreaks in the coming years. Increased surveillance efforts should be implemented with a focus on early-warning detection methods, and large-scale host and vector surveys should continue to fill gaps in knowledge.
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Affiliation(s)
- Jeremy V Camp
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Norbert Nowotny
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine Vienna, Vienna, Austria.,Department of Basic Medical Sciences, College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, United Arab Emirates
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32
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Comparative Pathology of West Nile Virus in Humans and Non-Human Animals. Pathogens 2020; 9:pathogens9010048. [PMID: 31935992 PMCID: PMC7168622 DOI: 10.3390/pathogens9010048] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/03/2020] [Accepted: 01/03/2020] [Indexed: 12/11/2022] Open
Abstract
West Nile virus (WNV) continues to be a major cause of human arboviral neuroinvasive disease. Susceptible non-human vertebrates are particularly diverse, ranging from commonly affected birds and horses to less commonly affected species such as alligators. This review summarizes the pathology caused by West Nile virus during natural infections of humans and non-human animals. While the most well-known findings in human infection involve the central nervous system, WNV can also cause significant lesions in the heart, kidneys and eyes. Time has also revealed chronic neurologic sequelae related to prior human WNV infection. Similarly, neurologic disease is a prominent manifestation of WNV infection in most non-human non-host animals. However, in some avian species, which serve as the vertebrate host for WNV maintenance in nature, severe systemic disease can occur, with neurologic, cardiac, intestinal and renal injury leading to death. The pathology seen in experimental animal models of West Nile virus infection and knowledge gains on viral pathogenesis derived from these animal models are also briefly discussed. A gap in the current literature exists regarding the relationship between the neurotropic nature of WNV in vertebrates, virus propagation and transmission in nature. This and other knowledge gaps, and future directions for research into WNV pathology, are addressed.
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33
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Duggal NK, Langwig KE, Ebel GD, Brault AC. On the Fly: Interactions Between Birds, Mosquitoes, and Environment That Have Molded West Nile Virus Genomic Structure Over Two Decades. JOURNAL OF MEDICAL ENTOMOLOGY 2019; 56:1467-1474. [PMID: 31549720 PMCID: PMC7182917 DOI: 10.1093/jme/tjz112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Indexed: 05/15/2023]
Abstract
West Nile virus (WNV) was first identified in North America almost 20 yr ago. In that time, WNV has crossed the continent and established enzootic transmission cycles, resulting in intermittent outbreaks of human disease that have largely been linked with climatic variables and waning avian seroprevalence. During the transcontinental dissemination of WNV, the original genotype has been displaced by two principal extant genotypes which contain an envelope mutation that has been associated with enhanced vector competence by Culex pipiens L. (Diptera: Culicidae) and Culex tarsalis Coquillett vectors. Analyses of retrospective avian host competence data generated using the founding NY99 genotype strain have demonstrated a steady reduction in viremias of house sparrows over time. Reciprocally, the current genotype strains WN02 and SW03 have demonstrated an inverse correlation between house sparrow viremia magnitude and the time since isolation. These data collectively indicate that WNV has evolved for increased avian viremia while house sparrows have evolved resistance to the virus such that the relative host competence has remained constant. Intrahost analyses of WNV evolution demonstrate that selection pressures are avian species-specific and purifying selection is greater in individual birds compared with individual mosquitoes, suggesting that the avian adaptive and/or innate immune response may impose a selection pressure on WNV. Phylogenomic, experimental evolutionary systems, and models that link viral evolution with climate, host, and vector competence studies will be needed to identify the relative effect of different selective and stochastic mechanisms on viral phenotypes and the capacity of newly evolved WNV genotypes for transmission in continuously changing landscapes.
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Affiliation(s)
- Nisha K Duggal
- Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, VA
| | - Kate E Langwig
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA
| | - Gregory D Ebel
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO
| | - Aaron C Brault
- Division of Vector-borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO
- Corresponding author, e-mail:
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34
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Hadfield J, Brito AF, Swetnam DM, Vogels CBF, Tokarz RE, Andersen KG, Smith RC, Bedford T, Grubaugh ND. Twenty years of West Nile virus spread and evolution in the Americas visualized by Nextstrain. PLoS Pathog 2019; 15:e1008042. [PMID: 31671157 PMCID: PMC6822705 DOI: 10.1371/journal.ppat.1008042] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
It has been 20 years since West Nile virus first emerged in the Americas, and since then, little progress has been made to control outbreaks caused by this virus. After its first detection in New York in 1999, West Nile virus quickly spread across the continent, causing an epidemic of human disease and massive bird die-offs. Now the virus has become endemic to the United States, where an estimated 7 million human infections have occurred, making it the leading mosquito-borne virus infection and the most common cause of viral encephalitis in the country. To bring new attention to one of the most important mosquito-borne viruses in the Americas, we provide an interactive review using Nextstrain: a visualization tool for real-time tracking of pathogen evolution (nextstrain.org/WNV/NA). Nextstrain utilizes a growing database of more than 2,000 West Nile virus genomes and harnesses the power of phylogenetics for students, educators, public health workers, and researchers to visualize key aspects of virus spread and evolution. Using Nextstrain, we use virus genomics to investigate the emergence of West Nile virus in the U S, followed by its rapid spread, evolution in a new environment, establishment of endemic transmission, and subsequent international spread. For each figure, we include a link to Nextstrain to allow the readers to directly interact with and explore the underlying data in new ways. We also provide a brief online narrative that parallels this review to further explain the data and highlight key epidemiological and evolutionary features (nextstrain.org/narratives/twenty-years-of-WNV). Mirroring the dynamic nature of outbreaks, the Nextstrain links provided within this paper are constantly updated as new West Nile virus genomes are shared publicly, helping to stay current with the research. Overall, our review showcases how genomics can track West Nile virus spread and evolution, as well as potentially uncover novel targeted control measures to help alleviate its public health burden.
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Affiliation(s)
- James Hadfield
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Anderson F. Brito
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Daniele M. Swetnam
- Department of Pathology, Microbiology and Immunology, University of California, Davis, Davis, California, United States of America
| | - Chantal B. F. Vogels
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Ryan E. Tokarz
- Department of Entomology, Iowa State University, Ames, Iowa, United States of America
| | - Kristian G. Andersen
- Department of Immunology and Microbiology, Scripps Research, La Jolla, California, United States of America
- Scripps Research Translational Institute, La Jolla, California, United States of America
| | - Ryan C. Smith
- Department of Entomology, Iowa State University, Ames, Iowa, United States of America
| | - Trevor Bedford
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Nathan D. Grubaugh
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
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35
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Bialosuknia SM, Tan Y, Zink SD, Koetzner CA, Maffei JG, Halpin RA, Mueller EA, Novotny M, Shilts M, Fedorova NB, Amedeo P, Das SR, Pickett B, Kramer LD, Ciota AT. Evolutionary dynamics and molecular epidemiology of West Nile virus in New York State: 1999-2015. Virus Evol 2019; 5:vez020. [PMID: 31341640 PMCID: PMC6642743 DOI: 10.1093/ve/vez020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Following its introduction into New York State (NYS) in 1999, West Nile virus (WNV; Flavivirus, Flaviviridae) underwent a rapid expansion throughout the USA and into Canada and Latin America. WNV has been characterized as being evolutionarily stable, with weak geographic structure, a dominance of purifying selection and limited adaptive change. We analyzed all available full-genome WNV sequences, focusing on the 543 available sequences from NYS, which included 495 newly sequenced 2000–15 isolates. In addition, we analyzed deep-sequencing data from 317 of these isolates. While our data are generally in agreement with the limited pace of evolutionary change and broad geographic and temporal mixing identified in other studies, we have identified some important exceptions. Most notably, there are 14 codons which demonstrated evidence of positive selection as determined by multiple models, including some positions with evidence of selection in NYS exclusively. Coincident with increased WNV activity, genotypes possessing one or more of these mutations, designated NY01, NY07, and NY10, have increased in prevalence in recent years and displaced historic strains. In addition, we have found a geographical bias with many of these mutations, which suggests selective pressures and adaptations could be regional. Lastly, our deep-sequencing data suggest both increased overall diversity in avian tissue isolates relative to mosquito isolates and multiple non-synonymous minority variants that are both host-specific and retained over time and space. Together, these data provide novel insight into the evolutionary pressures on WNV and the need for continued genetic surveillance and characterization of emergent strains.
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Affiliation(s)
- Sean M Bialosuknia
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, 5668 State Farm Road, Slingerlands, NY, USA
| | - Yi Tan
- Department of Medicine, Vanderbilt University Medical Center, Nashville, 1161 21st Street, Nashville, TN, USA
| | - Steven D Zink
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, 5668 State Farm Road, Slingerlands, NY, USA
| | - Cheri A Koetzner
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, 5668 State Farm Road, Slingerlands, NY, USA
| | - Joseph G Maffei
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, 5668 State Farm Road, Slingerlands, NY, USA
| | - Rebecca A Halpin
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Emmi A Mueller
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Mark Novotny
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Meghan Shilts
- Department of Medicine, Vanderbilt University Medical Center, Nashville, 1161 21st Street, Nashville, TN, USA
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Nadia B Fedorova
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Paolo Amedeo
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Suman R Das
- Department of Medicine, Vanderbilt University Medical Center, Nashville, 1161 21st Street, Nashville, TN, USA
| | - Brett Pickett
- J. Craig Venter Institute, Virology, 9605 Medical Center Drive, Rockville, MD, USA
| | - Laura D Kramer
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, 5668 State Farm Road, Slingerlands, NY, USA
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Rensselear, NY, USA
| | - Alexander T Ciota
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, 5668 State Farm Road, Slingerlands, NY, USA
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Rensselear, NY, USA
- Corresponding author: E-mail:
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Endless Forms: Within-Host Variation in the Structure of the West Nile Virus RNA Genome during Serial Passage in Bird Hosts. mSphere 2019; 4:4/3/e00291-19. [PMID: 31243074 PMCID: PMC6595145 DOI: 10.1128/msphere.00291-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The enzymes that copy RNA genomes lack proofreading, and viruses that possess RNA genomes, such as West Nile virus, rapidly diversify into swarms of mutant lineages within a host. Intrahost variation of the primary genomic sequence of RNA viruses has been studied extensively because the extent of this variation shapes key virus phenotypes. However, RNA genomes also form complex secondary structures based on within-genome nucleotide complementarity, which are critical regulators of the cyclization of the virus genome that is necessary for efficient replication and translation. We sought to characterize variation in these secondary structures within populations of West Nile virus during serial passage in three bird species. Our study indicates that the intrahost population of West Nile virus is a diverse assortment of RNA secondary structures that should be considered in future analyses of intrahost viral diversity, but some regions that are critical for genome cyclization are conserved within hosts. Besides potential impacts on viral replication, structural diversity can influence the efficacy of small RNA antiviral therapies. RNA viruses are infamous for their high rates of mutation, which produce swarms of genetic variants within individual hosts. To date, analyses of intrahost genetic diversity have focused on the primary genome sequence. However, virus phenotypes are shaped not only by primary sequence but also by the secondary structures into which this sequence folds. Such structures enable viral replication, translation, and binding of small RNAs, yet within-host variation at the structural level has not been adequately explored. We characterized the structural diversity of the 5′ untranslated region (UTR) of populations of West Nile virus (WNV) that had been subject to five serial passages in triplicate in each of three bird species. Viral genomes were sampled from host serum samples at each passage (n = 45 populations) and subjected to next-generation sequencing. For populations derived from passages 1, 3, and 5 (n = 9 populations), we predicted the impact of each mutation occurring at a frequency of ≥1% on the secondary structure of the 5′ UTR. As expected, mutations in double-stranded (DS) regions of the 5′ UTR stem structures caused structural changes of significantly greater magnitude than did mutations in single-stranded (SS) regions. Despite the greater impact of mutations in DS regions, mutations in DS and SS regions occurred at similar frequencies, with no evidence of enhanced selection against mutation in DS regions. In contrast, mutations in two regions that mediate genome cyclization and thereby regulate replication and translation, the 5′ cyclization sequence and the UAR flanking stem (UFS), were suppressed in all three hosts. IMPORTANCE The enzymes that copy RNA genomes lack proofreading, and viruses that possess RNA genomes, such as West Nile virus, rapidly diversify into swarms of mutant lineages within a host. Intrahost variation of the primary genomic sequence of RNA viruses has been studied extensively because the extent of this variation shapes key virus phenotypes. However, RNA genomes also form complex secondary structures based on within-genome nucleotide complementarity, which are critical regulators of the cyclization of the virus genome that is necessary for efficient replication and translation. We sought to characterize variation in these secondary structures within populations of West Nile virus during serial passage in three bird species. Our study indicates that the intrahost population of West Nile virus is a diverse assortment of RNA secondary structures that should be considered in future analyses of intrahost viral diversity, but some regions that are critical for genome cyclization are conserved within hosts. Besides potential impacts on viral replication, structural diversity can influence the efficacy of small RNA antiviral therapies.
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Reyes-Ruiz JM, Osuna-Ramos JF, Bautista-Carbajal P, Jaworski E, Soto-Acosta R, Cervantes-Salazar M, Angel-Ambrocio AH, Castillo-Munguía JP, Chávez-Munguía B, De Nova-Ocampo M, Routh A, Del Ángel RM, Salas-Benito JS. Mosquito cells persistently infected with dengue virus produce viral particles with host-dependent replication. Virology 2019; 531:1-18. [PMID: 30844508 DOI: 10.1016/j.virol.2019.02.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 02/22/2019] [Accepted: 02/26/2019] [Indexed: 11/26/2022]
Abstract
Dengue viruses (DENV) are important arboviruses that can establish a persistent infection in its mosquito vector Aedes. Mosquitoes have a short lifetime in nature which makes trying to study the processes that take place during persistent viral infections in vivo. Therefore, C6/36 cells have been used to study this type of infection. C6/36 cells persistently infected with DENV 2 produce virions that cannot infect BHK -21 cells. We hypothesized that the following passages in mosquito cells have a deleterious impact on DENV fitness in vertebrate cells. Here, we demonstrated that the viral particles released from persistently infected cells were infectious to mosquito but not to vertebrate cells. This host restriction occurs at the replication level and is associated with several mutations in the DENV genome. In summary, our findings provide new information about viral replication fitness in a host-dependent manner.
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Affiliation(s)
- José Manuel Reyes-Ruiz
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Juan Fidel Osuna-Ramos
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Patricia Bautista-Carbajal
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Elizabeth Jaworski
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA
| | - Rubén Soto-Acosta
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA
| | - Margot Cervantes-Salazar
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | | | - Juan Pablo Castillo-Munguía
- Maestría en Ciencias en Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico
| | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Mónica De Nova-Ocampo
- Maestría en Ciencias en Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico
| | - Andrew Routh
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA; Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Rosa María Del Ángel
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico.
| | - Juan Santiago Salas-Benito
- Maestría en Ciencias en Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico; Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico.
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Worwa G, Hutton AA, Brault AC, Reisen WK. Comparative fitness of West Nile virus isolated during California epidemics. PLoS Negl Trop Dis 2019; 13:e0007135. [PMID: 30716113 PMCID: PMC6375641 DOI: 10.1371/journal.pntd.0007135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 02/14/2019] [Accepted: 01/07/2019] [Indexed: 11/30/2022] Open
Abstract
West Nile virus (WNV) has been circulating in California since its first detection in 2003, causing repeated outbreaks affecting public, wildlife and veterinary health. Epidemics of WNV are difficult to predict due to the multitude of factors influencing transmission dynamics among avian and mosquito hosts. Typically, high levels of WNV amplification are required for outbreaks to occur, and therefore associated viral strains may exhibit enhanced virulence and mortality in competent bird species resulting in increased mosquito infection prevalence. In our previous study, most WNV isolates made from California during 2007-08 showed increased fitness when competed in House Finches (HOFI, Haemorhous mexicanus) and Culex tarsalis Coquillett mosquitoes against COAV997-5nt, a genetically marked recombinant virus derived from a 2003 California strain. Herein, we evaluated the competitive fitness of WNV strains isolated during California epidemics in 2004, 2005, 2007, 2011 and 2012 against COAV997-5nt. These outbreak isolates did not produce elevated mortality in HOFIs, but replicated more efficiently than did COAV997-5nt based on quantification of WNV RNA copies in sera, thereby demonstrating increased competitive fitness. Oral co-infections in Cx. tarsalis resulted in similar virus-specific infection and transmission rates, indicating that outbreak isolates did not have a fitness advantage over COAV997-5nt. Collectively, WNV isolates from outbreaks demonstrated relatively greater avian, but not vector, replicative fitness compared to COAV997-5nt, similar to previously characterized non-outbreak isolates of WNV. Our results indicated that ecological rather than viral factors may facilitate WNV amplification to outbreak levels, but monitoring viral phenotypes through competitive fitness studies may provide insight into altered replication and transmission potential among emerging WNV strains.
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Affiliation(s)
- Gabriella Worwa
- Center for Vectorborne Diseases, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, United States of America
| | - Andra A. Hutton
- Center for Vectorborne Diseases, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, United States of America
| | - Aaron C. Brault
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America
| | - William K. Reisen
- Center for Vectorborne Diseases, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, California, United States of America
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Lozano-Fuentes S, Kenney JL, Varnado W, Byrd BD, Burkhalter KL, Savage HM. Susceptibility and Vectorial Capacity of American Aedes albopictus and Aedes aegypti (Diptera: Culicidae) to American Zika Virus Strains. JOURNAL OF MEDICAL ENTOMOLOGY 2019; 56:233-240. [PMID: 30102327 PMCID: PMC6781865 DOI: 10.1093/jme/tjy114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Indexed: 06/08/2023]
Abstract
The rapid expansion of Zika virus (ZIKV), following the recent outbreaks of Chikungunya virus, overwhelmed the public health infrastructure in many countries and alarmed many in the scientific community. Aedes aegypti (L.) (Diptera: Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) have previously been incriminated as the vectors of these pathogens in addition to dengue virus. In our study, we challenged low generation Ae. aegypti (Chiapas, Mexico) and Ae. albopictus (North Carolina, Mississippi), with three strains of ZIKV, Puerto Rico (GenBank: KU501215), Honduras (GenBank: KX694534), and Miami (GenBank: MF988743). Following an oral challenge with 107.5 PFU/ml of the Puerto Rico strain, we observed high infection and dissemination rates in both species (95%). We report estimated transmission rates for both species (74 and 33%, for Ae. aegypti (L.) (Diptera: Culicidae) and Ae. albopictus (Skuse) (Diptera: Culicidae), respectively), and the presence of a probable salivary gland barrier in Ae. albopictus to Zika virus. Finally, we calculated vectorial capacity for both species and found that Ae. albopictus had a slightly lower vectorial capacity when compared with Ae. aegypti.Second Language Abstract: La rápida expansión del virus Zika, poco después de las epidemias de chikungunya, rebaso la infraestructura de salud pública en muchos países y sorprendió a muchos en la comunidad científica. Notablemente, Aedes aegypti y Aedes albopictus transmiten estos patógenos además del virus del dengue. En este estudio se expusieron con tres cepas americanas de virus Zika a grupos de Aedes aegypti y Aedes albopictus de generación reciente. Encontramos altos porcentajes de infección y diseminación en ambas especies (95%). Se reporta, la transmisión viral en ambas especies (74 y 33%, para Aedes aegypti and Aedes albopictus, respectivamente) y una probable barrera a nivel de glándulas salivarías. Finalmente, calculamos la capacidad vectorial para ambas especies.
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Affiliation(s)
- Saul Lozano-Fuentes
- Arbovirus Diseases Branch, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521
| | - Joan L. Kenney
- Arbovirus Diseases Branch, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521
| | - Wendy Varnado
- Mississippi State Department of Health, 570 East Woodrow Wilson Avenue, Jackson, MS 39216
| | - Brian D. Byrd
- Vector-borne Infectious Disease Laboratory, Western Carolina University, 3971 Little Savannah Road, CHHS 416, Cullowhee, NC 28723
| | - Kristen L. Burkhalter
- Arbovirus Diseases Branch, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521
| | - Harry M. Savage
- Arbovirus Diseases Branch, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521
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Azar SR, Rossi SL, Haller SH, Yun R, Huang JH, Plante JA, Zhou J, Olano JP, Roundy CM, Hanley KA, Weaver SC, Vasilakis N. ZIKV Demonstrates Minimal Pathologic Effects and Mosquito Infectivity in Viremic Cynomolgus Macaques. Viruses 2018; 10:v10110661. [PMID: 30469417 PMCID: PMC6267344 DOI: 10.3390/v10110661] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 11/13/2018] [Accepted: 11/19/2018] [Indexed: 12/15/2022] Open
Abstract
To evaluate the effects of ZIKV infection on non-human primates (NHPs), as well as to investigate whether these NHPs develop sufficient viremia to infect the major urban vector mosquito, Aedes aegypti, four cynomolgus macaques (Macaca fascicularis) were subcutaneously infected with 5.0 log10 focus-forming units (FFU) of DNA clone-derived ZIKV strain FSS13025 (Asian lineage, Cambodia, 2010). Following infection, the animals were sampled (blood, urine, tears, and saliva), underwent daily health monitoring, and were exposed to Ae. aegypti at specified time points. All four animals developed viremia, which peaked 3⁻4 days post-infection at a maximum value of 6.9 log10 genome copies/mL. No virus was detected in urine, tears, or saliva. Infection by ZIKV caused minimal overt disease: serum biochemistry and CBC values largely fell within the normal ranges, and cytokine elevations were minimal. Strikingly, the minimally colonized population of Ae. aegypti exposed to viremic animals demonstrated a maximum infection rate of 26% during peak viremia, with two of the four macaques failing to infect a single mosquito at any time point. These data indicate that cynomolgus macaques may be an effective model for ZIKV infection of humans and highlights the relative refractoriness of Ae. aegypti for ZIKV infection at the levels of viremia observed.
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Affiliation(s)
- Sasha R Azar
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Shannan L Rossi
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA.
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Sherry H Haller
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Ruimei Yun
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Jing H Huang
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Jessica A Plante
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Jiehua Zhou
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Juan P Olano
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Christopher M Roundy
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Kathryn A Hanley
- Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA.
| | - Scott C Weaver
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA.
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Nikos Vasilakis
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA.
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Growth and adaptation of Zika virus in mammalian and mosquito cells. PLoS Negl Trop Dis 2018; 12:e0006880. [PMID: 30418969 PMCID: PMC6258428 DOI: 10.1371/journal.pntd.0006880] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 11/26/2018] [Accepted: 09/28/2018] [Indexed: 01/02/2023] Open
Abstract
The recent emergence of Zika virus (ZIKV) in the Americas coincident with increased caseloads of microcephalic infants and Guillain-Barre syndrome has prompted a flurry of research on ZIKV. Much of the research is difficult to compare or repeat because individual laboratories use different virus isolates, growth conditions, and quantitative assays. Here we obtained three readily available contemporary ZIKV isolates and the prototype Ugandan isolate. We generated stocks of each on Vero mammalian cells (ZIKVmam) and C6/36 mosquito cells (ZIKVmos), determined titers by different assays side-by-side, compared growth characteristics using one-step and multi-step growth curves on Vero and C6/36 cells, and examined plaque phenotype. ZIKV titers consistently peaked earlier on Vero cells than on C6/36 cells. Contemporary ZIKV isolates reached peak titer most quickly in a multi-step growth curve when the amplifying cell line was the same as the titering cell line (e.g., ZIKVmam titered on Vero cells). Growth of ZIKVmam on mosquito cells was particularly delayed. These data suggest that the ability to infect and/or replicate in insect cells is limited after growth in mammalian cells. In addition, ZIKVmos typically had smaller, more homogenous plaques than ZIKVmam in a standard plaque assay. We hypothesized that the plaque size difference represented early adaptation to growth in mammalian cells. We plaque purified representative-sized plaques from ZIKVmos and ZIKVmam. ZIKVmos isolates maintained the initial phenotype while plaques from ZIKVmam isolates became larger with passaging. Our results underscore the importance of the cells used to produce viral stocks and the potential for adaptation with minimal cell passages. In addition, these studies provide a foundation to compare current and emerging ZIKV isolates in vitro and in vivo.
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Koo C, Tien WP, Xu H, Ong J, Rajarethinam J, Lai YL, Ng LC, Hapuarachchi HC. Highly Selective Transmission Success of Dengue Virus Type 1 Lineages in a Dynamic Virus Population: An Evolutionary and Fitness Perspective. iScience 2018; 6:38-51. [PMID: 30240624 PMCID: PMC6137288 DOI: 10.1016/j.isci.2018.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 06/19/2018] [Accepted: 07/13/2018] [Indexed: 11/30/2022] Open
Abstract
Arbovirus transmission is modulated by host, vector, virus, and environmental factors. Even though viral fitness plays a salient role in host and vector adaptation, the transmission success of individual strains in a heterogeneous population may be stochastic. Our large-scale molecular epidemiological analyses of a dengue virus type 1 population revealed that only a subset of strains (16.7%; n = 6) were able to sustain transmission, despite the population being widely dispersed, dynamic, and heterogeneous. The overall dominance was variable even among the “established” lineages, albeit sharing comparable evolutionary characteristics and replication profiles. These findings indicated that virological parameters alone were unlikely to have a profound effect on the survival of viral lineages, suggesting an important role for non-viral factors in the transmission success of lineages. Our observations, therefore, emphasize the strategic importance of a holistic understanding of vector, human host, and viral factors in the control of vector-borne diseases. The sustained transmission of dengue virus 1 lineages is highly selective The overall dominance is variable even among the “established” lineages The lineage dominance is not merely determined by virus evolution and fitness The non-viral factors play an important role in the survival of virus lineages
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Affiliation(s)
- Carmen Koo
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore
| | - Wei Ping Tien
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore
| | - Helen Xu
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore
| | - Janet Ong
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore
| | - Jayanthi Rajarethinam
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore
| | - Yee Ling Lai
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore
| | - Lee-Ching Ng
- Environmental Health Institute, National Environment Agency, 11, Biopolis Way, #06-05-08, Singapore 138667, Singapore; School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
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Morley VJ, Noval MG, Chen R, Weaver SC, Vignuzzi M, Stapleford KA, Turner PE. Chikungunya virus evolution following a large 3'UTR deletion results in host-specific molecular changes in protein-coding regions. Virus Evol 2018; 4:vey012. [PMID: 29942653 PMCID: PMC6007266 DOI: 10.1093/ve/vey012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The 3′untranslated region (UTR) in alphavirus genomes functions in virus replication and plays a role in determining virus host range. However, the molecular evolution of virus UTRs is understudied compared to the evolution of protein-coding regions. Chikungunya virus (CHIKV) has the longest 3′UTR among the alphaviruses (500–700 nt), and 3′UTR length and sequence structure vary substantially among different CHIKV lineages. Previous studies showed that genomic deletions and insertions are key drivers of CHIKV 3′UTR evolution. Inspired by hypothesized deletion events in the evolutionary history of CHIKV, we used experimental evolution to examine CHIKV adaptation in response to a large 3′UTR deletion. We engineered a CHIKV mutant with a 258 nt deletion in the 3′UTR (ΔDR1/2). This deletion reduced viral replication on mosquito cells, but did not reduce replication on mammalian cells. To examine how selective pressures from vertebrate and invertebrate hosts shape CHIKV evolution after a deletion in the 3′UTR, we passaged ΔDR1/2 virus populations strictly on primate cells, strictly on mosquito cells, or with alternating primate/mosquito cell passages. We found that virus populations passaged on a single host cell line increased in fitness relative to the ancestral deletion mutant on their selected host, and viruses that were alternately passaged improved on both hosts. Surprisingly, whole genome sequencing revealed few changes in the 3′UTR of passaged populations. Rather, virus populations evolved improved fitness through mutations in protein coding regions that were associated with specific hosts.
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Affiliation(s)
- Valerie J Morley
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06511-8934, USA
| | | | - Rubing Chen
- Institute for Human Infections and Immunity and Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Scott C Weaver
- Institute for Human Infections and Immunity and Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Marco Vignuzzi
- Viral Populations and Pathogenesis Unit, Institut Pasteur, Paris, France
| | | | - Paul E Turner
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06511-8934, USA.,Program in Microbiology, Yale School of Medicine, New Haven, CT, USA
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44
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Mosquitoes Transmit Unique West Nile Virus Populations during Each Feeding Episode. Cell Rep 2018; 19:709-718. [PMID: 28445723 DOI: 10.1016/j.celrep.2017.03.076] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/26/2017] [Accepted: 03/28/2017] [Indexed: 11/23/2022] Open
Abstract
Arthropod-borne viruses (arboviruses), such as Zika virus, chikungunya virus, and West Nile virus (WNV), pose continuous threats to emerge and cause large epidemics. Often, these events are associated with novel virus variants optimized for local transmission that first arise as minorities within a host. Thus, the conditions that regulate the frequency of intrahost variants are important determinants of emergence. Here, we describe the dynamics of WNV genetic diversity during its transmission cycle. By temporally sampling saliva from individual mosquitoes, we demonstrate that virus populations expectorated by mosquitoes are highly diverse and unique to each feeding episode. After transmission to birds, however, most genetic diversity is removed by strong purifying selection. Further, transmission of potentially mosquito-adaptive WNV variants is strongly influenced by genetic drift in mosquitoes. These results highlight the complex evolutionary forces a novel virus variant must overcome to alter infection phenotypes at the population level.
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45
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How Do Virus-Mosquito Interactions Lead to Viral Emergence? Trends Parasitol 2018; 34:310-321. [PMID: 29305089 DOI: 10.1016/j.pt.2017.12.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 12/11/2017] [Accepted: 12/13/2017] [Indexed: 12/27/2022]
Abstract
Arboviruses such as West Nile, Zika, chikungunya, dengue, and yellow fever viruses have become highly significant global pathogens through unexpected, explosive outbreaks. While the rapid progression and frequency of recent arbovirus outbreaks is associated with long-term changes in human behavior (globalization, urbanization, climate change), there are direct mosquito-virus interactions which drive shifts in host range and alter virus transmission. This review summarizes how virus-mosquito interactions are critical for these viruses to become global pathogens at molecular, physiological, evolutionary, and epidemiological scales. Integrated proactive approaches are required in order to effectively manage the emergence of mosquito-borne arboviruses, which appears likely to continue into the indefinite future.
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46
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Nelson CW, Sibley SD, Kolokotronis SO, Hamer GL, Newman CM, Anderson TK, Walker ED, Kitron UD, Brawn JD, Ruiz MO, Goldberg TL. Selective constraint and adaptive potential of West Nile virus within and among naturally infected avian hosts and mosquito vectors. Virus Evol 2018; 4:vey013. [PMID: 29942654 PMCID: PMC6007309 DOI: 10.1093/ve/vey013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Arthropod-borne viruses are among the most genetically constrained RNA viruses, yet they have a remarkable propensity to adapt and emerge. We studied wild birds and mosquitoes naturally infected with West Nile virus (WNV) in a 'hot spot' of virus transmission in Chicago, IL, USA. We generated full coding WNV genome sequences from spatiotemporally matched bird and mosquito samples using high-throughput sequencing, allowing a molecular evolutionary assessment with deep coverage. Mean FST among samples was 0.66 (±0.02 SE) and was bimodal, with mean nucleotide diversity being higher between samples (interhost πN = 0.001; πS = 0.024) than within them (intrahost πN < 0.0001; πS < 0.001). Eight genomic sites with FST > 1.01 (in the PrM, NS2a, NS3, NS4b, and 5'-noncoding genomic regions) showed bird versus mosquito variant frequency differences of >30 per cent and/or polymorphisms fixed in ≥5 host or vector individuals, suggesting host tropism for these variants. However, phylogenetic analyses demonstrated a lack of grouping by bird or mosquito, most inter-sample differences were synonymous (mean interhost πN/πS = 0.04), and there was no significant difference between hosts and vectors in either their nucleotide diversities or levels of purifying selection (mean intrahost πN/πS = 0.28 in birds and πN/πS = 0.21 in mosquitoes). This finding contrasts with the 'trade-off' and 'selective sieve' hypotheses that have been proposed and tested in the laboratory, which predict strong host versus vector effects on WNV genetic variation, with heightened selective constraint in birds alternating with heightened viral diversity in mosquitoes. Overall, our data show WNV to be highly selectively constrained within and between both hosts and vectors but still able to vary at a limited number of sites across the genome. Such site-specific plasticity in the face of overall selective constraint may offer a mechanism whereby highly constrained viruses such as WNV and its relatives can still adapt and emerge.
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Affiliation(s)
- Chase W Nelson
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Samuel D Sibley
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sergios-Orestis Kolokotronis
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
- Department of Epidemiology and Biostatistics, School of Public Health, SUNY Downstate Medical Center, Brooklyn, NY 11203-2098, USA
| | - Gabriel L Hamer
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475, USA
| | - Christina M Newman
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Tavis K Anderson
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Edward D Walker
- Department of Microbiology and Molecular Genetics, Michigan State University, Lansing, MI 48824-4320, USA
| | - Uriel D Kitron
- Department of Environmental Studies, Emory University, Atlanta, GA 30322, USA
| | - Jeffrey D Brawn
- Department of Natural Resources and Environmental Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Marilyn O Ruiz
- Department of Pathobiology, University of Illinois, Urbana, IL 61802, USA
| | - Tony L Goldberg
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
- Global Health Institute, University of Wisconsin-Madison, Madison, WI 53706, USA
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47
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Smith DR, Sprague TR, Hollidge BS, Valdez SM, Padilla SL, Bellanca SA, Golden JW, Coyne SR, Kulesh DA, Miller LJ, Haddow AD, Koehler JW, Gromowski GD, Jarman RG, Alera MTP, Yoon IK, Buathong R, Lowen RG, Kane CD, Minogue TD, Bavari S, Tesh RB, Weaver SC, Linthicum KJ, Pitt ML, Nasar F. African and Asian Zika Virus Isolates Display Phenotypic Differences Both In Vitro and In Vivo. Am J Trop Med Hyg 2017; 98:432-444. [PMID: 29280428 DOI: 10.4269/ajtmh.17-0685] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Zika virus (ZIKV) is a mosquito-borne member of the genus Flavivirus that has emerged since 2007 to cause outbreaks in Africa, Asia, Oceania, and most recently, in the Americas. Here, we used an isolate history as well as genetic and phylogenetic analyses to characterize three low-passage isolates representing African (ArD 41525) and Asian (CPC-0740, SV0127-14) lineages to investigate the potential phenotypic differences in vitro and in vivo. The African isolate displayed a large plaque phenotype (∼3-4 mm) on Vero and HEK-293 cells, whereas the Asian isolates either exhibited a small plaque phenotype (∼1-2 mm) or did not produce any plaques. In multistep replication kinetics in nine different vertebrate and insect cell lines, the African isolate consistently displayed faster replication kinetics and yielded ∼10- to 10,000-fold higher peak virus titers (infectious or RNA copies) compared with the Asian isolates. Oral exposure of Aedes aegypti mosquitoes with the African isolate yielded higher infection and dissemination rates compared with the Asian isolates. Infection of Ifnar1-/- mice with the African isolate produced a uniformly fatal disease, whereas infection with the Asian isolates produced either a delay in time-to-death or a significantly lower mortality rate. Last, the African isolate was > 10,000-fold more virulent than the Asian isolates in an interferon type I antibody blockade mouse model. These data demonstrate substantial phenotypic differences between low-passage African and Asian isolates both in vitro and in vivo and warrant further investigation. They also highlight the need for basic characterization of ZIKV isolates, as the utilization of the uncharacterized isolates could have consequences for animal model and therapeutic/vaccine development.
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Affiliation(s)
- Darci R Smith
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Thomas R Sprague
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Bradley S Hollidge
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Stephanie M Valdez
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Susana L Padilla
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Stephanie A Bellanca
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Joseph W Golden
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Susan R Coyne
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - David A Kulesh
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Lynn Jean Miller
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Andrew D Haddow
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Jeff W Koehler
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | | | | | - Maria Theresa P Alera
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - In-Kyu Yoon
- International Vaccine Institute, Seoul, Republic of Korea
| | - Rome Buathong
- Department of Disease Control, Bureau of Epidemiology, Ministry of Public Health, Nonthaburi, Thailand
| | - Robert G Lowen
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Christopher D Kane
- Molecular and Translational Sciences Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Timothy D Minogue
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Sina Bavari
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Robert B Tesh
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas.,Department of Pathology, University of Texas Medical Branch, Galveston, Texas.,Institute for Human Infections and Immunity, Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Scott C Weaver
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas.,Department of Pathology, University of Texas Medical Branch, Galveston, Texas.,Institute for Human Infections and Immunity, Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Kenneth J Linthicum
- Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, Gainesville, Florida
| | - Margaret L Pitt
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Farooq Nasar
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas
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48
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Bono LM, Smith LB, Pfennig DW, Burch CL. The emergence of performance trade‐offs during local adaptation: insights from experimental evolution. Mol Ecol 2017; 26:1720-1733. [DOI: 10.1111/mec.13979] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/15/2016] [Accepted: 12/19/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Lisa M. Bono
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| | - Leno B. Smith
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| | - David W. Pfennig
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| | - Christina L. Burch
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
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49
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Perrier A, Peyraud R, Rengel D, Barlet X, Lucasson E, Gouzy J, Peeters N, Genin S, Guidot A. Enhanced in planta Fitness through Adaptive Mutations in EfpR, a Dual Regulator of Virulence and Metabolic Functions in the Plant Pathogen Ralstonia solanacearum. PLoS Pathog 2016; 12:e1006044. [PMID: 27911943 PMCID: PMC5135139 DOI: 10.1371/journal.ppat.1006044] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/05/2016] [Indexed: 11/18/2022] Open
Abstract
Experimental evolution of the plant pathogen Ralstonia solanacearum, where bacteria were maintained on plant lineages for more than 300 generations, revealed that several independent single mutations in the efpR gene from populations propagated on beans were associated with fitness gain on bean. In the present work, novel allelic efpR variants were isolated from populations propagated on other plant species, thus suggesting that mutations in efpR were not solely associated to a fitness gain on bean, but also on additional hosts. A transcriptomic profiling and phenotypic characterization of the efpR deleted mutant showed that EfpR acts as a global catabolic repressor, directly or indirectly down-regulating the expression of multiple metabolic pathways. EfpR also controls virulence traits such as exopolysaccharide production, swimming and twitching motilities and deletion of efpR leads to reduced virulence on tomato plants after soil drenching inoculation. We studied the impact of the single mutations that occurred in efpR during experimental evolution and found that these allelic mutants displayed phenotypic characteristics similar to the deletion mutant, although not behaving as complete loss-of-function mutants. These adaptive mutations therefore strongly affected the function of efpR, leading to an expanded metabolic versatility that should benefit to the evolved clones. Altogether, these results indicated that EfpR is a novel central player of the R. solanacearum virulence regulatory network. Independent mutations therefore appeared during experimental evolution in the evolved clones, on a crucial node of this network, to favor adaptation to host vascular tissues through regulatory and metabolic rewiring. Among plant pathogens of major economic and food crops, Ralstonia solanacearum, the causal agent of bacterial wilt, is recognized as one of the most destructive plant bacterial diseases. In addition, the emergence of new pathotypes, more aggressive and adapted to new hosts, has been reported. During an evolution experiment of R. solanacearum, where bacteria were maintained on plant lineages for more than 300 generations, we demonstrated that several single mutations in the regulatory gene efpR were associated with fitness gain on plants. However, the function of the EfpR regulator was totally unknown. In this work, we provided evidence that EfpR controls several metabolic pathways and important virulence traits of R. solanacearum. We then demonstrated that the single mutations selected in the efpR gene during the evolution experiment strongly alter the efpR expression, and thus enlarge the metabolic capacities of the bacterial cell. Altogether, our study reveals that EfpR is a novel key component of the complex regulatory network of the R. solanacearum cell, tightly linking the bacterial metabolism to virulence in response to multiple environmental signals.
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Affiliation(s)
- Anthony Perrier
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Rémi Peyraud
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - David Rengel
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Xavier Barlet
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | | | - Jérôme Gouzy
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Nemo Peeters
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Stéphane Genin
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
- * E-mail: (SG); (AG)
| | - Alice Guidot
- LIPM, Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
- * E-mail: (SG); (AG)
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50
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Xia H, Beck AS, Gargili A, Forrester N, Barrett ADT, Bente DA. Transstadial Transmission and Long-term Association of Crimean-Congo Hemorrhagic Fever Virus in Ticks Shapes Genome Plasticity. Sci Rep 2016; 6:35819. [PMID: 27775001 PMCID: PMC5075774 DOI: 10.1038/srep35819] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 10/04/2016] [Indexed: 02/05/2023] Open
Abstract
The trade-off hypothesis, the current paradigm of arbovirus evolution, proposes that cycling between vertebrate and invertebrate hosts presents significant constraints on genetic change of arboviruses. Studying these constraints in mosquito-borne viruses has led to a new understanding of epizootics. The trade-off hypothesis is assumed to be applicable to tick-borne viruses too, although studies are lacking. Tick-borne Crimean-Congo hemorrhagic fever virus (CCHFV), a member of the family Bunyaviridae, is a major cause of severe human disease worldwide and shows an extraordinary amount of genetic diversity compared to other arboviruses, which has been linked to increased virulence and emergence in new environments. Using a transmission model for CCHFV, utilizing the main vector tick species and mice plus next generation sequencing, we detected a substantial number of consensus-level mutations in CCHFV recovered from ticks after only a single transstadial transmission, whereas none were detected in CCHFV obtained from the mammalian host. Furthermore, greater viral intra-host diversity was detected in the tick compared to the vertebrate host. Long-term association of CCHFV with its tick host for 1 year demonstrated mutations in the viral genome become fixed over time. These findings suggest that the trade-off hypothesis may not be accurate for all arboviruses.
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Affiliation(s)
- Han Xia
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA.,Galveston National Laboratory, Galveston TX, USA.,Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Andrew S Beck
- Department of Pathology, and Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX, USA
| | | | - Naomi Forrester
- Department of Pathology, and Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX, USA
| | - Alan D T Barrett
- Department of Pathology, and Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX, USA
| | - Dennis A Bente
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA.,Galveston National Laboratory, Galveston TX, USA
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