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Luria-Pérez R, Sánchez-Vargas LA, Muñoz-López P, Mellado-Sánchez G. Mucosal Vaccination: A Promising Alternative Against Flaviviruses. Front Cell Infect Microbiol 2022; 12:887729. [PMID: 35782117 PMCID: PMC9241634 DOI: 10.3389/fcimb.2022.887729] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/10/2022] [Indexed: 12/15/2022] Open
Abstract
The Flaviviridae are a family of positive-sense, single-stranded RNA enveloped viruses, and their members belong to a single genus, Flavivirus. Flaviviruses are found in mosquitoes and ticks; they are etiological agents of: dengue fever, Japanese encephalitis, West Nile virus infection, Zika virus infection, tick-borne encephalitis, and yellow fever, among others. Only a few flavivirus vaccines have been licensed for use in humans: yellow fever, dengue fever, Japanese encephalitis, tick-borne encephalitis, and Kyasanur forest disease. However, improvement is necessary in vaccination strategies and in understanding of the immunological mechanisms involved either in the infection or after vaccination. This is especially important in dengue, due to the immunological complexity of its four serotypes, cross-reactive responses, antibody-dependent enhancement, and immunological interference. In this context, mucosal vaccines represent a promising alternative against flaviviruses. Mucosal vaccination has several advantages, as inducing long-term protective immunity in both mucosal and parenteral tissues. It constitutes a friendly route of antigen administration because it is needle-free and allows for a variety of antigen delivery systems. This has promoted the development of several ways to stimulate immunity through the direct administration of antigens (e.g., inactivated virus, attenuated virus, subunits, and DNA), non-replicating vectors (e.g., nanoparticles, liposomes, bacterial ghosts, and defective-replication viral vectors), and replicating vectors (e.g., Salmonella enterica, Lactococcus lactis, Saccharomyces cerevisiae, and viral vectors). Because of these characteristics, mucosal vaccination has been explored for immunoprophylaxis against pathogens that enter the host through mucosae or parenteral areas. It is suitable against flaviviruses because this type of immunization can stimulate the parenteral responses required after bites from flavivirus-infected insects. This review focuses on the advantages of mucosal vaccine candidates against the most relevant flaviviruses in either humans or animals, providing supporting data on the feasibility of this administration route for future clinical trials.
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Affiliation(s)
- Rosendo Luria-Pérez
- Hospital Infantil de México Federico Gómez, Unidad de Investigación en Enfermedades Hemato-Oncológicas, Ciudad de México, Mexico
| | - Luis A. Sánchez-Vargas
- Department of Cell and Molecular Biology, Institute for Immunology and Informatics, University of Rhode Island, Providence, RI, United States
| | - Paola Muñoz-López
- Hospital Infantil de México Federico Gómez, Unidad de Investigación en Enfermedades Hemato-Oncológicas, Ciudad de México, Mexico
- Posgrado en Biomedicina y Biotecnología Molecular, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Gabriela Mellado-Sánchez
- Unidad de Desarrollo e Investigación en Bioterapéuticos (UDIBI), Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
- Laboratorio Nacional para Servicios Especializados de Investigación, Desarrollo e Innovación (I+D+i) para Farmoquímicos y Biotecnológicos, LANSEIDI-FarBiotec-CONACyT, Ciudad de México, Mexico
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Wahaab A, Mustafa BE, Hameed M, Stevenson NJ, Anwar MN, Liu K, Wei J, Qiu Y, Ma Z. Potential Role of Flavivirus NS2B-NS3 Proteases in Viral Pathogenesis and Anti-flavivirus Drug Discovery Employing Animal Cells and Models: A Review. Viruses 2021; 14:44. [PMID: 35062249 PMCID: PMC8781031 DOI: 10.3390/v14010044] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 02/07/2023] Open
Abstract
Flaviviruses are known to cause a variety of diseases in humans in different parts of the world. There are very limited numbers of antivirals to combat flavivirus infection, and therefore new drug targets must be explored. The flavivirus NS2B-NS3 proteases are responsible for the cleavage of the flavivirus polyprotein, which is necessary for productive viral infection and for causing clinical infections; therefore, they are a promising drug target for devising novel drugs against different flaviviruses. This review highlights the structural details of the NS2B-NS3 proteases of different flaviviruses, and also describes potential antiviral drugs that can interfere with the viral protease activity, as determined by various studies. Moreover, optimized in vitro reaction conditions for studying the NS2B-NS3 proteases of different flaviviruses may vary and have been incorporated in this review. The increasing availability of the in silico and crystallographic/structural details of flavivirus NS2B-NS3 proteases in free and drug-bound states can pave the path for the development of promising antiflavivirus drugs to be used in clinics. However, there is a paucity of information available on using animal cells and models for studying flavivirus NS2B-NS3 proteases, as well as on the testing of the antiviral drug efficacy against NS2B-NS3 proteases. Therefore, on the basis of recent studies, an effort has also been made to propose potential cellular and animal models for the study of flavivirus NS2B-NS3 proteases for the purposes of exploring flavivirus pathogenesis and for testing the efficacy of possible drugs targets, in vitro and in vivo.
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Affiliation(s)
- Abdul Wahaab
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
| | - Bahar E Mustafa
- Sub Campus Toba Tek Singh, University of Agriculture, Faisalabad 36050, Pakistan;
| | - Muddassar Hameed
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
- Department of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Polytechnic Institute, State University, Fralin Life Sciences Building, 360 W Campus Blacksburg, Blacksburg, VA 24061, USA
| | - Nigel J. Stevenson
- Royal College of Surgeons in Ireland, Medical University of Bahrain, Busaiteen, Adliya 15503, Bahrain;
- Viral Immunology Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, D02 R590 Dublin, Ireland
| | - Muhammad Naveed Anwar
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
| | - Ke Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
| | - Jianchao Wei
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
| | - Yafeng Qiu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
| | - Zhiyong Ma
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai 200241, China; (A.W.); (M.H.); (M.N.A.); (K.L.); (J.W.)
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An Unsupervised Algorithm for Host Identification in Flaviviruses. Life (Basel) 2021; 11:life11050442. [PMID: 34069049 PMCID: PMC8157105 DOI: 10.3390/life11050442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/07/2021] [Accepted: 05/12/2021] [Indexed: 12/28/2022] Open
Abstract
Early characterization of emerging viruses is essential to control their spread, such as the Zika Virus outbreak in 2014. Among other non-viral factors, host information is essential for the surveillance and control of virus spread. Flaviviruses (genus Flavivirus), akin to other viruses, are modulated by high mutation rates and selective forces to adapt their codon usage to that of their hosts. However, a major challenge is the identification of potential hosts for novel viruses. Usually, potential hosts of emerging zoonotic viruses are identified after several confirmed cases. This is inefficient for deterring future outbreaks. In this paper, we introduce an algorithm to identify the host range of a virus from its raw genome sequences. The proposed strategy relies on comparing codon usage frequencies across viruses and hosts, by means of a normalized Codon Adaptation Index (CAI). We have tested our algorithm on 94 flaviviruses and 16 potential hosts. This novel method is able to distinguish between arthropod and vertebrate hosts for several flaviviruses with high values of accuracy (virus group 91.9% and host type 86.1%) and specificity (virus group 94.9% and host type 79.6%), in comparison to empirical observations. Overall, this algorithm may be useful as a complementary tool to current phylogenetic methods in monitoring current and future viral outbreaks by understanding host–virus relationships.
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Yang J, Jing X, Yi W, Li XD, Yao C, Zhang B, Zheng Z, Wang H, Gong P. Crystal structure of a tick-borne flavivirus RNA-dependent RNA polymerase suggests a host adaptation hotspot in RNA viruses. Nucleic Acids Res 2021; 49:1567-1580. [PMID: 33406260 PMCID: PMC7897508 DOI: 10.1093/nar/gkaa1250] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/09/2020] [Accepted: 12/15/2020] [Indexed: 01/07/2023] Open
Abstract
The RNA-dependent RNA polymerases (RdRPs) encoded by RNA viruses represent a unique class of nucleic acid polymerases. RdRPs are essential in virus life cycle due to their central role in viral genome replication/transcription processes. However, their contribution in host adaption has not been well documented. By solving the RdRP crystal structure of the tick-borne encephalitis virus (TBEV), a tick-borne flavivirus, and comparing the structural and sequence features with mosquito-borne flavivirus RdRPs, we found that a region between RdRP catalytic motifs B and C, namely region B-C, clearly bears host-related diversity. Inter-virus substitutions of region B-C sequence were designed in both TBEV and mosquito-borne Japanese encephalitis virus backbones. While region B-C substitutions only had little or moderate effect on RdRP catalytic activities, virus proliferation was not supported by these substitutions in both virus systems. Importantly, a TBEV replicon-derived viral RNA replication was significantly reduced but not abolished by the substitution, suggesting the involvement of region B-C in viral and/or host processes beyond RdRP catalysis. A systematic structural analysis of region B-C in viral RdRPs further emphasizes its high level of structure and length diversity, providing a basis to further refine its relevance in RNA virus-host interactions in a general context.
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Affiliation(s)
- Jieyu Yang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuping Jing
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenfu Yi
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
| | - Xiao-Dan Li
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
| | - Chen Yao
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bo Zhang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
- Drug Discovery Center for Infectious Diseases, Nankai University, Tianjin 300350, China
| | - Zhenhua Zheng
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
| | | | - Peng Gong
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, No.44 Xiao Hong Shan, Wuhan, Hubei 430071, China
- Drug Discovery Center for Infectious Diseases, Nankai University, Tianjin 300350, China
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Bahk YY, Park SH, Kim-Jeon MD, Oh SS, Jung H, Jun H, Kim KA, Park JM, Ahn SK, Lee J, Choi EJ, Moon BS, Gong YW, Kwon MJ, Kim TS. Monitoring Culicine Mosquitoes (Diptera: Culicidae) as a Vector of Flavivirus in Incheon Metropolitan City and Hwaseong-Si, Gyeonggi-Do, Korea, during 2019. THE KOREAN JOURNAL OF PARASITOLOGY 2020; 58:551-558. [PMID: 33202507 PMCID: PMC7672235 DOI: 10.3347/kjp.2020.58.5.551] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/07/2020] [Indexed: 12/20/2022]
Abstract
The flaviviruses are small single-stranded RNA viruses that are typically transmitted by mosquitoes or tick vectors and are etiological agents of acute zoonotic infections. The viruses are found around the world and account for significant cases of human diseases. We investigated population of culicine mosquitoes in central region of Korean Peninsula, Incheon Metropolitan City and Hwaseong-si. Aedes vexans nipponii was the most frequently collected mosquitoes (56.5%), followed by Ochlerotatus dorsalis (23.6%), Anopheles spp. (10.9%), and Culex pipiens complex (5.9%). In rural regions of Hwaseong, Aedes vexans nipponii was the highest population (62.9%), followed by Ochlerotatus dorsalis (23.9%) and Anopheles spp. (12.0%). In another rural region of Incheon (habitat of migratory birds), Culex pipiens complex was the highest population (31.4%), followed by Ochlerotatus dorsalis (30.5%), and Aedes vexans vexans (27.5%). Culex pipiens complex was the predominant species in the urban region (84.7%). Culicine mosquitoes were identified at the species level, pooled up to 30 mosquitoes each, and tested for flaviviral RNA using the SYBR Green-based RT-PCR and confirmed by cDNA sequencing. Three of the assayed 2,683 pools (989 pools without Anopheles spp.) were positive for Culex flaviviruses, an insect-specific virus, from Culex pipiens pallens collected at the habitats for migratory birds in Incheon. The maximum likelihood estimation (the estimated number) for Culex pipiens pallens positive for Culex flavivirus was 25. Although viruses responsible for mosquito-borne diseases were not identified, we encourage intensified monitoring and long-term surveillance of both vector and viruses in the interest of global public health.
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Affiliation(s)
- Young Yil Bahk
- Department of Biotechnology, College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
| | - Seo Hye Park
- Department of Parasitology and Tropical Medicine & Global Resource Bank of Parasitic Protozoa Pathogens, Inha University School of Medicine, Incheon 22212, Korea
| | - Myung-Deok Kim-Jeon
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Sung-Suck Oh
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Haneul Jung
- Department of Parasitology and Tropical Medicine & Global Resource Bank of Parasitic Protozoa Pathogens, Inha University School of Medicine, Incheon 22212, Korea
| | - Hojong Jun
- Department of Parasitology and Tropical Medicine & Global Resource Bank of Parasitic Protozoa Pathogens, Inha University School of Medicine, Incheon 22212, Korea
| | - Kyung-Ae Kim
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Jong Myong Park
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Seong Kyu Ahn
- Department of Parasitology and Tropical Medicine & Global Resource Bank of Parasitic Protozoa Pathogens, Inha University School of Medicine, Incheon 22212, Korea
| | - Jinyoung Lee
- Department of Parasitology and Tropical Medicine & Global Resource Bank of Parasitic Protozoa Pathogens, Inha University School of Medicine, Incheon 22212, Korea
| | - Eun-Jeong Choi
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Bag-Sou Moon
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Young Woo Gong
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Mun Ju Kwon
- Department of Infectious Diseases Diagnosis, Incheon Metropolitan City Institute of Public Health and Environment, Incheon 22320, Korea
| | - Tong-Soo Kim
- Department of Parasitology and Tropical Medicine & Global Resource Bank of Parasitic Protozoa Pathogens, Inha University School of Medicine, Incheon 22212, Korea
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Hewson I, Johnson MR, Tibbetts IR. An Unconventional Flavivirus and Other RNA Viruses in the Sea Cucumber (Holothuroidea; Echinodermata) Virome. Viruses 2020; 12:v12091057. [PMID: 32972018 PMCID: PMC7551563 DOI: 10.3390/v12091057] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 09/18/2020] [Accepted: 09/21/2020] [Indexed: 12/11/2022] Open
Abstract
Sea cucumbers (Holothuroidea; Echinodermata) are ecologically significant constituents of benthic marine habitats. We surveilled RNA viruses inhabiting eight species (representing four families) of holothurian collected from four geographically distinct locations by viral metagenomics, including a single specimen of Apostichopus californicus affected by a hitherto undocumented wasting disease. The RNA virome comprised genome fragments of both single-stranded positive sense and double stranded RNA viruses, including those assigned to the Picornavirales, Ghabrivirales, and Amarillovirales. We discovered an unconventional flavivirus genome fragment which was most similar to a shark virus. Ghabivirales-like genome fragments were most similar to fungal totiviruses in both genome architecture and homology and had likely infected mycobiome constituents. Picornavirales, which are commonly retrieved in host-associated viral metagenomes, were similar to invertebrate transcriptome-derived picorna-like viruses. The greatest number of viral genome fragments was recovered from the wasting A. californicus library compared to the asymptomatic A. californicus library. However, reads from the asymptomatic library recruited to nearly all recovered wasting genome fragments, suggesting that they were present but not well represented in the grossly normal specimen. These results expand the known host range of flaviviruses and suggest that fungi and their viruses may play a role in holothurian ecology.
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Affiliation(s)
- Ian Hewson
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA;
- Correspondence: ; Tel.: +1-607-255-0151
| | | | - Ian R. Tibbetts
- School of Biological Sciences, University of Queensland, St Lucia, Brisbane, QLD 4072, Australia;
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Parry R, Asgari S. Discovery of Novel Crustacean and Cephalopod Flaviviruses: Insights into the Evolution and Circulation of Flaviviruses between Marine Invertebrate and Vertebrate Hosts. J Virol 2019; 93:e00432-19. [PMID: 31068424 PMCID: PMC6600200 DOI: 10.1128/jvi.00432-19] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/23/2019] [Indexed: 12/21/2022] Open
Abstract
Most described flaviviruses (family Flaviviridae) are disease-causing pathogens of vertebrates maintained in zoonotic cycles between mosquitoes or ticks and vertebrate hosts. Poor sampling of flaviviruses outside vector-borne flaviviruses such as Zika virus and dengue virus has presented a narrow understanding of flavivirus diversity and evolution. In this study, we discovered three crustacean flaviviruses (Gammarus chevreuxi flavivirus, Gammarus pulex flavivirus, and Crangon crangon flavivirus) and two cephalopod flaviviruses (Southern Pygmy squid flavivirus and Firefly squid flavivirus). Bayesian and maximum likelihood phylogenetic methods demonstrate that crustacean flaviviruses form a well-supported clade and share a more closely related ancestor with terrestrial vector-borne flaviviruses than with classical insect-specific flaviviruses. In addition, we identify variants of Wenzhou shark flavivirus in multiple gazami crab (Portunus trituberculatus) populations, with active replication supported by evidence of an active RNA interference response. This suggests that Wenzhou shark flavivirus moves horizontally between sharks and gazami crabs in ocean ecosystems. Analyses of the mono- and dinucleotide composition of marine flaviviruses compared to that of flaviviruses with known host status suggest that some marine flaviviruses share a nucleotide bias similar to that of vector-borne flaviviruses. Furthermore, we identify crustacean flavivirus endogenous viral elements that are closely related to elements of terrestrial vector-borne flaviviruses. Taken together, these data provide evidence of flaviviruses circulating between marine vertebrates and invertebrates, expand our understanding of flavivirus host range, and offer potential insights into the evolution and emergence of terrestrial vector-borne flaviviruses.IMPORTANCE Some flaviviruses are known to cause disease in vertebrates and are typically transmitted by blood-feeding arthropods such as ticks and mosquitoes. While an ever-increasing number of insect-specific flaviviruses have been described, we have a narrow understanding of flavivirus incidence and evolution. To expand this understanding, we discovered a number of novel flaviviruses that infect a range of crustaceans and cephalopod hosts. Phylogenetic analyses of these novel marine flaviviruses suggest that crustacean flaviviruses share a close ancestor to all terrestrial vector-borne flaviviruses, and squid flaviviruses are the most divergent of all known flaviviruses to date. Additionally, our results indicate horizontal transmission of a marine flavivirus between crabs and sharks. Taken together, these data suggest that flaviviruses move horizontally between invertebrates and vertebrates in ocean ecosystems. This study demonstrates that flavivirus invertebrate-vertebrate host associations have arisen in flaviviruses at least twice and may potentially provide insights into the emergence or origin of terrestrial vector-borne flaviviruses.
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Affiliation(s)
- Rhys Parry
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Sassan Asgari
- Australian Infectious Disease Research Centre, School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia
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Abstract
The tick-borne pathogen Powassan virus is a rare cause of encephalitis in North America and the Russian Far East. The number of documented cases described since the discovery of Powassan virus in 1958 may be <150, although detection of cases has increased over the past decade. In the United States, the incidence of Powassan virus infections expanded from the estimated 1 case per year prior to 2005 to 10 cases per year during the subsequent decade. The increased detection rate may be associated with several factors, including enhanced surveillance, the availability of improved laboratory diagnostic methods, the expansion of the vector population, and, perhaps, altered human activities that lead to more exposure. Nonetheless, it remains unclear whether Powassan virus is indeed an emerging threat or if enzootic cycles in nature remain more-or-less stable with periodic fluctuations of host and vector population sizes. Despite the low disease incidence, the approximately 10% to 15% case fatality rate of neuroinvasive Powassan virus infection and the temporary or prolonged sequelae in >50% of survivors make Powassan virus a medical concern requiring the attention of public health authorities and clinicians. The medical importance of Powassan virus justifies more research on developing specific and effective treatments and prevention and control measures.
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Affiliation(s)
- Gábor Kemenesi
- Virological Research Group, Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Institute of Biology, Faculty of Sciences, University of Pécs, Pécs, Hungary
| | - Krisztián Bányai
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
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Arthropod EVs mediate dengue virus transmission through interaction with a tetraspanin domain containing glycoprotein Tsp29Fb. Proc Natl Acad Sci U S A 2018; 115:E6604-E6613. [PMID: 29946031 DOI: 10.1073/pnas.1720125115] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Dengue virus (DENV) is a mosquito-borne flavivirus that causes dengue fever in humans, worldwide. Using in vitro cell lines derived from Aedes albopictus and Aedes aegypti, the primary vectors of DENV, we report that DENV2/DENV3-infected cells secrete extracellular vesicles (EVs), including exosomes, containing infectious viral RNA and proteins. A full-length DENV2 genome, detected in arthropod EVs, was infectious to naïve mosquito and mammalian cells, including human-skin keratinocytes and blood endothelial cells. Cryo-electron microscopy showed mosquito EVs with a size range from 30 to 250 nm. Treatments with RNase A, Triton X-100, and 4G2 antibody-bead binding assays showed that infectious DENV2-RNA and proteins are contained inside EVs. Viral plaque formation and dilution assays also showed securely contained infectious viral RNA and proteins in EVs are transmitted to human cells. Up-regulated HSP70 upon DENV2 infection showed no role in viral replication and transmission through EVs. In addition, qRT-PCR and immunoblotting results revealed that DENV2 up-regulates expression of a mosquito tetraspanin-domain-containing glycoprotein, designated as Tsp29Fb, in A. aegypti mosquitoes, cells, and EVs. RNAi-mediated silencing and antibody blocking of Tsp29Fb resulted in reduced DENV2 loads in both mosquito cells and EVs. Immunoprecipitation showed Tsp29Fb to directly interact with DENV2 E-protein. Furthermore, treatment with GW4869 (exosome-release inhibitor) affected viral burden, direct interaction of Tsp29Fb with E-protein and EV-mediated transmission of viral RNA and proteins to naïve human cells. In summary, we report a very important finding on EV-mediated transmission of DENV2 from arthropod to mammalian cells through interactions with an arthropod EVs-enriched marker Tsp29Fb.
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Does adaptation to vertebrate codon usage relate to flavivirus emergence potential? PLoS One 2018; 13:e0191652. [PMID: 29385205 PMCID: PMC5792106 DOI: 10.1371/journal.pone.0191652] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 01/09/2018] [Indexed: 12/30/2022] Open
Abstract
Codon adaptation index (CAI) is a measure of synonymous codon usage biases given a usage reference. Through mutation, selection, and drift, viruses can optimize their replication efficiency and produce more offspring, which could increase the chance of secondary transmission. To evaluate how higher CAI towards the host has been associated with higher viral titers, we explored temporal trends of several historic and extensively sequenced zoonotic flaviviruses and relationships within the genus itself. To showcase evolutionary and epidemiological relationships associated with silent, adaptive synonymous changes of viruses, we used codon usage tables from human housekeeping and antiviral immune genes, as well as tables from arthropod vectors and vertebrate species involved in the flavivirus maintenance cycle. We argue that temporal trends of CAI changes could lead to a better understanding of zoonotic emergences, evolutionary dynamics, and host adaptation. CAI appears to help illustrate historically relevant trends of well-characterized viruses, in different viral species and genetic diversity within a single species. CAI can be a useful tool together with in vivo and in vitro kinetics, phylodynamics, and additional functional genomics studies to better understand species trafficking and viral emergence in a new host.
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Kuno G, Mackenzie JS, Junglen S, Hubálek Z, Plyusnin A, Gubler DJ. Vertebrate Reservoirs of Arboviruses: Myth, Synonym of Amplifier, or Reality? Viruses 2017; 9:E185. [PMID: 28703771 PMCID: PMC5537677 DOI: 10.3390/v9070185] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/10/2017] [Accepted: 07/10/2017] [Indexed: 02/07/2023] Open
Abstract
The rapid succession of the pandemic of arbovirus diseases, such as dengue, West Nile fever, chikungunya, and Zika fever, has intensified research on these and other arbovirus diseases worldwide. Investigating the unique mode of vector-borne transmission requires a clear understanding of the roles of vertebrates. One major obstacle to this understanding is the ambiguity of the arbovirus definition originally established by the World Health Organization. The paucity of pertinent information on arbovirus transmission at the time contributed to the notion that vertebrates played the role of reservoir in the arbovirus transmission cycle. Because this notion is a salient feature of the arbovirus definition, it is important to reexamine its validity. This review addresses controversial issues concerning vertebrate reservoirs and their role in arbovirus persistence in nature, examines the genesis of the problem from a historical perspective, discusses various unresolved issues from multiple points of view, assesses the present status of the notion in light of current knowledge, and provides options for a solution to resolve the issue.
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Affiliation(s)
- Goro Kuno
- Formerly at the Division of Vector-Borne Infectious Diseases, Centers for Control and Prevention, Fort Collins, CO, USA.
| | - John S Mackenzie
- Faculty of Medical Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia.
- Division of Microbiology & Infectious Diseases, PathWest, Nedlands, Western Australia 6009.
| | - Sandra Junglen
- Institute of Virology, Charité-Universitätsmedizin Berlin, Helmut-Ruska-Haus, Chariteplatz 1, 10117 Berlin, Germany.
| | - Zdeněk Hubálek
- Institute of Vertebrate Biology, Academy of Sciences of Czech Republic, 60365 Brno, Czech Republic.
| | - Alexander Plyusnin
- Department of Virology, University of Helsinki, Haartmaninkatu 3, University of Helsinki, 00014 Helsinki, Finland.
| | - Duane J Gubler
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Rd., Singapore 169857 Singapore.
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12
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Abstract
Most viruses in the genus Flavivirus are horizontally transmitted between hematophagous arthropods and vertebrate hosts, but some are maintained in arthropod- or vertebrate-restricted transmission cycles. Flaviviruses maintained by vertebrate-only transmission are commonly referred to as no known vector (NKV) flaviviruses. Fourteen species and two subtypes of NKV flaviviruses are recognized by the International Committee on Taxonomy of Viruses (ICTV), and Tamana bat virus potentially belongs to this group. NKV flaviviruses have been isolated in nature almost exclusively from bats and rodents; exceptions are the two isolates of Dakar bat virus recovered from febrile humans and the recent isolations of Sokoluk virus from field-collected ticks, which raises questions as to whether it should remain classified as an NKV flavivirus. There is evidence to suggest that two other NKV flaviviruses, Entebbe bat virus and Yokose virus, may also infect arthropods in nature. The best characterized bat- and rodent-associated NKV flaviviruses are Rio Bravo and Modoc viruses, respectively, but both have received limited research attention compared to many of their arthropod-infecting counterparts. Herein, we provide a comprehensive review of NKV flaviviruses, placing a particular emphasis on their classification, host range, geographic distribution, replication kinetics, pathogenesis, transmissibility and molecular biology.
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13
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Discovery of Novel Viruses in Mosquitoes from the Zambezi Valley of Mozambique. PLoS One 2016; 11:e0162751. [PMID: 27682810 PMCID: PMC5040392 DOI: 10.1371/journal.pone.0162751] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 08/26/2016] [Indexed: 11/19/2022] Open
Abstract
Mosquitoes carry a wide variety of viruses that can cause vector-borne infectious diseases and affect both human and veterinary public health. Although Mozambique can be considered a hot spot for emerging infectious diseases due to factors such as a rich vector population and a close vector/human/wildlife interface, the viral flora in mosquitoes have not previously been investigated. In this study, viral metagenomics was employed to analyze the viral communities in Culex and Mansonia mosquitoes in the Zambezia province of Mozambique. Among the 1.7 and 2.6 million sequences produced from the Culex and Mansonia samples, respectively, 3269 and 983 reads were classified as viral sequences. Viruses belonging to the Flaviviridae, Rhabdoviridae and Iflaviridae families were detected, and different unclassified single- and double-stranded RNA viruses were also identified. A near complete genome of a flavivirus, tentatively named Cuacua virus, was obtained from the Mansonia mosquitoes. Phylogenetic analysis of this flavivirus, using the NS5 amino acid sequence, showed that it grouped with 'insect-specific' viruses and was most closely related to Nakiwogo virus previously identified in Uganda. Both mosquito genera had viral sequences related to Rhabdoviruses, and these were most closely related to Culex tritaeniorhynchus rhabdovirus (CTRV). The results from this study suggest that several viruses specific for insects belonging to, for example, the Flaviviridae and Rhabdoviridae families, as well as a number of unclassified RNA viruses, are present in mosquitoes in Mozambique.
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Vasilakis N, Tesh RB. Insect-specific viruses and their potential impact on arbovirus transmission. Curr Opin Virol 2015; 15:69-74. [PMID: 26322695 DOI: 10.1016/j.coviro.2015.08.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 08/10/2015] [Accepted: 08/12/2015] [Indexed: 11/15/2022]
Abstract
Arthropod-borne viruses (arboviruses) are the causative agents of significant morbidity and mortality among humans and animals globally. In the past few years, the widespread adoption of next generation sequencing and metagenomics has led to a new era of virus discovery, where many novel viruses have been documented, exhibiting a restricted host-range in mosquitoes. They represent a wide-range of insect-specific viruses within the families of Bunyaviridae, Flaviviridae, Mesoniviridae, Reoviridae, Rhabdoviridae, Togaviridae, and the newly recognized taxon of Negeviruses. Collectively, their discovery has opened new vistas about the extent of viral diversity and evolution, their influence on vector competence and ability of their insect hosts to transmit human pathogens (e.g. arboviruses), and their potential development as biological control agents or novel vaccine platforms.
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Affiliation(s)
- Nikos Vasilakis
- Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases, Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, TX 77555-0609, United States.
| | - Robert B Tesh
- Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases, Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, TX 77555-0609, United States.
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15
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Carrera JP, Guzman H, Beltrán D, Díaz Y, López-Vergès S, Torres-Cosme R, Popov V, Widen SG, Wood TG, Weaver SC, Cáceres-Carrera L, Vasilakis N, Tesh RB. Mercadeo Virus: A Novel Mosquito-Specific Flavivirus from Panama. Am J Trop Med Hyg 2015; 93:1014-9. [PMID: 26304915 DOI: 10.4269/ajtmh.15-0117] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 07/09/2015] [Indexed: 12/20/2022] Open
Abstract
Viruses in the genus Flavivirus (family Flaviviridae) include many arthropod-borne viruses of public health and veterinary importance. However, during the past two decades an explosion of novel insect-specific flaviviruses (ISFs), some closely related to vertebrate pathogens, have been discovered. Although many flavivirus pathogens of vertebrates have been isolated from naturally infected mosquitoes in Panama, ISFs have not previously been reported from the country. This report describes the isolation and characterization of a novel ISF, tentatively named Mercadeo virus (MECDV), obtained from Culex spp. mosquitoes collected in Panama. Two MECDV isolates were sequenced and cluster phylogenetically with cell-fusing agent virus (CFAV) and Nakiwogo virus (NAKV) to form a distinct lineage within the insect-specific group of flaviviruses.
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Affiliation(s)
- Jean-Paul Carrera
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Hilda Guzman
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Davis Beltrán
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Yamilka Díaz
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Sandra López-Vergès
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Rolando Torres-Cosme
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Vsevolod Popov
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Steven G Widen
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Thomas G Wood
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Scott C Weaver
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Lorenzo Cáceres-Carrera
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Nikos Vasilakis
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
| | - Robert B Tesh
- Department of Virology and Biotechnology Research, Gorgas Memorial Institute of Health Studies, Panama City, Panama; Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama; School of Medicine, Columbus University, Panama City, Panama; Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, Texas; Institute for Human Infectious and Immunity, The University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
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16
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Evolutionary and phenotypic analysis of live virus isolates suggests arthropod origin of a pathogenic RNA virus family. Proc Natl Acad Sci U S A 2015; 112:7536-41. [PMID: 26038576 DOI: 10.1073/pnas.1502036112] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The evolutionary origins of arboviruses are unknown because their typical dual host tropism is paraphyletic within viral families. Here we studied one of the most diversified and medically relevant RNA virus families, the Bunyaviridae, in which four of five established genera are transmitted by arthropods. We define two cardinally novel bunyavirus groups based on live isolation of 26 viral strains from mosquitoes (Jonchet virus [JONV], eight strains; Ferak virus [FERV], 18 strains). Both viruses were incapable of replicating at vertebrate-typical temperatures but replicated efficiently in insect cells. Replication involved formation of virion-sense RNA (vRNA) and mRNA, including cap-snatching activity. SDS/PAGE, mass spectrometry, and Edman degradation identified translation products corresponding to virion-associated RNA-dependent RNA polymerase protein (RdRp), glycoprotein precursor protein, glycoproteins Gn and Gc, as well as putative nonstructural proteins NSs and NSm. Distinct virion morphologies suggested ancient evolutionary divergence, with bunyavirus-typical morphology for FERV (spheres of 60-120 nm) as opposed to an unusual bimorphology for JONV (tubular virions of 60 × 600 nm and spheres of 80 nm). Both viruses were genetically equidistant from all other bunyaviruses, showing <15% amino acid identity in the RdRp palm domain. Both had different and unique conserved genome termini, as in separate bunyavirus genera. JONV and FERV define two novel sister taxons to the superclade of orthobunyaviruses, tospoviruses, and hantaviruses. Phylogenetic ancestral state reconstruction with probabilistic hypothesis testing suggested ancestral associations with arthropods at deep nodes throughout the bunyavirus tree. Our findings suggest an arthropod origin of bunyaviruses.
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17
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Hoshino K, Isawa H, Kuwata R, Tajima S, Takasaki T, Iwabuchi K, Sawabe K, Kobayashi M, Sasaki T. Establishment and characterization of two new cell lines from the mosquito Armigeres subalbatus (Coquillett) (Diptera: Culicidae). In Vitro Cell Dev Biol Anim 2015; 51:672-9. [PMID: 25761724 DOI: 10.1007/s11626-015-9883-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 02/20/2015] [Indexed: 11/25/2022]
Abstract
Armigeres subalbatus (Coquillett) is a medically important mosquito and a model species for immunology research. We successfully established two cell lines from the neonate larvae of A. subalbatus using two different media. To our knowledge, this is the first report of an established Armigeres mosquito cell line. The cell lines, designated as Ar-3 and Ar-13, consist of adherent and diploid cells with compact colonies. Both these cell lines grow slowly after passage at a split ratio of 1:5 and a population doubling time of 2.7 and 3.0 d, respectively. Random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) was used to confirm that these lines correspond to the species of origin and are clearly distinct from seven other insect cell lines. Furthermore, reverse-transcription PCR was used to demonstrate that the Ar-3 cell line is susceptible to the Japanese encephalitis virus and two insect flaviviruses associated with Culex and Aedes mosquitoes but relatively insensitive to dengue virus. These data indicate that the newly established cell lines are cellular models of A. subalbatus as well as beneficial tools for the propagation of viruses associated with the Armigeres mosquito.
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Affiliation(s)
- Keita Hoshino
- Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
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18
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Moureau G, Cook S, Lemey P, Nougairede A, Forrester NL, Khasnatinov M, Charrel RN, Firth AE, Gould EA, de Lamballerie X. New insights into flavivirus evolution, taxonomy and biogeographic history, extended by analysis of canonical and alternative coding sequences. PLoS One 2015; 10:e0117849. [PMID: 25719412 PMCID: PMC4342338 DOI: 10.1371/journal.pone.0117849] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 01/02/2015] [Indexed: 12/20/2022] Open
Abstract
To generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with Culex spp. mosquitoes. We analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. Based on the presumed introduction of yellow fever virus into the Americas via the transatlantic slave trade, we extrapolated a timescale for a relevant subset of flaviviruses whose evolutionary history, shows that different Culex-spp. associated flaviviruses have been introduced from the Old World to the New World on at least five separate occasions, with 2 different sets of factors likely to have contributed to the dispersal of the different viruses. We also discuss the significance of programmed ribosomal frameshifting in a central region of the polyprotein open reading frame in some mosquito-associated flaviviruses.
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Affiliation(s)
- Gregory Moureau
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Shelley Cook
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Philippe Lemey
- Department of Microbiology and Immunology, Rega Institute, KU Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Antoine Nougairede
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Naomi L. Forrester
- Institute for Human Infections and Immunity and Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, United States of America
| | - Maxim Khasnatinov
- Centre for Ecology and Hydrology, Maclean Building, Benson Lane, Crowmarsh, Gifford, Wallingford, Oxfordshire, OX10, United Kingdom
| | - Remi N. Charrel
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Andrew E. Firth
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
| | - Ernest A. Gould
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
| | - Xavier de Lamballerie
- Aix Marseille Université, IRD French Institute of Research for Development, EHESP French School of Public Health, EPV UMR_D 190 Emergence des Pathologies Virales, Marseille, France
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19
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Grisenti M, Vázquez A, Herrero L, Cuevas L, Perez-Pastrana E, Arnoldi D, Rosà R, Capelli G, Tenorio A, Sánchez-Seco MP, Rizzoli A. Wide detection of Aedes flavivirus in north-eastern Italy – a European hotspot of emerging mosquito-borne diseases. J Gen Virol 2015; 96:420-430. [DOI: 10.1099/vir.0.069625-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Michela Grisenti
- Department of Veterinary Sciences, University of Torino, largo Paolo Braccini 2, 10095 Grugliasco, Torino, Italy
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Trento, Italy
| | - Ana Vázquez
- Laboratory of Arboviruses and Viral Imported Diseases, Institute of Health ‘Carlos III’, Ctra Pozuelo-Majadahonda, Km 2, 28220 Majadahonda, Madrid, Spain
| | - Laura Herrero
- Laboratory of Arboviruses and Viral Imported Diseases, Institute of Health ‘Carlos III’, Ctra Pozuelo-Majadahonda, Km 2, 28220 Majadahonda, Madrid, Spain
| | - Laureano Cuevas
- Electron Microscopy Department, National Center of Microbiology, Institute of Health ‘Carlos III’, Ctra Pozuelo-Majadahonda, Km 2, 28220 Majadahonda, Madrid, Spain
| | - Esperanza Perez-Pastrana
- Electron Microscopy Department, National Center of Microbiology, Institute of Health ‘Carlos III’, Ctra Pozuelo-Majadahonda, Km 2, 28220 Majadahonda, Madrid, Spain
| | - Daniele Arnoldi
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Trento, Italy
| | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Trento, Italy
| | - Gioia Capelli
- Laboratory of Parasitology, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell’Università 10, 35020 Legnaro, Padova, Italy
| | - Antonio Tenorio
- Laboratory of Arboviruses and Viral Imported Diseases, Institute of Health ‘Carlos III’, Ctra Pozuelo-Majadahonda, Km 2, 28220 Majadahonda, Madrid, Spain
| | - Maria Paz Sánchez-Seco
- Laboratory of Arboviruses and Viral Imported Diseases, Institute of Health ‘Carlos III’, Ctra Pozuelo-Majadahonda, Km 2, 28220 Majadahonda, Madrid, Spain
| | - Annapaola Rizzoli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Trento, Italy
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20
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Saiyasombat R, Carrillo-Tripp J, Miller WA, Bredenbeek PJ, Blitvich BJ. Substitution of the premembrane and envelope protein genes of Modoc virus with the homologous sequences of West Nile virus generates a chimeric virus that replicates in vertebrate but not mosquito cells. Virol J 2014; 11:150. [PMID: 25151534 PMCID: PMC4148964 DOI: 10.1186/1743-422x-11-150] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 08/19/2014] [Indexed: 11/23/2022] Open
Abstract
Background Most known flaviviruses, including West Nile virus (WNV), are maintained in natural transmission cycles between hematophagous arthropods and vertebrate hosts. Other flaviviruses such as Modoc virus (MODV) and Culex flavivirus (CxFV) have host ranges restricted to vertebrates and insects, respectively. The genetic elements that modulate the differential host ranges and transmission cycles of these viruses have not been identified. Methods Fusion polymerase chain reaction (PCR) was used to replace the capsid (C), premembrane (prM) and envelope (E) genes and the prM-E genes of a full-length MODV infectious cDNA clone with the corresponding regions of WNV and CxFV. Fusion products were directly transfected into baby hamster kidney-derived cells that stably express T7 RNA polymerase. At 4 days post-transfection, aliquots of each supernatant were inoculated onto vertebrate (BHK-21 and Vero) and mosquito (C6/36) cells which were then assayed for evidence of viral infection by reverse transcription-PCR, Western blot and plaque assay. Results Chimeric virus was recovered in cells transfected with the fusion product containing the prM-E genes of WNV. The virus could infect vertebrate but not mosquito cells. The in vitro replication kinetics and yields of the chimeric virus were similar to MODV but the chimeric virus produced larger plaques. Chimeric virus was not recovered in cells transfected with any of the other fusion products. Conclusions Our data indicate that genetic elements outside of the prM-E gene region of MODV condition its vertebrate-specific phenotype.
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Affiliation(s)
| | | | | | | | - Bradley J Blitvich
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
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21
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Walker T, Jeffries CL, Mansfield KL, Johnson N. Mosquito cell lines: history, isolation, availability and application to assess the threat of arboviral transmission in the United Kingdom. Parasit Vectors 2014; 7:382. [PMID: 25141888 PMCID: PMC4150944 DOI: 10.1186/1756-3305-7-382] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 08/06/2014] [Indexed: 01/28/2023] Open
Abstract
Mosquitoes are highly effective vectors for transmission of human and animal pathogens. Understanding the relationship between pathogen and vector is vital in developing strategies to predict and prevent transmission. Cell lines derived from appropriate mosquito hosts provide a relatively simple tool for investigating the interaction between the host and viruses transmitted by mosquitoes. This review provides a brief overview of the development of mosquito cell lines, methods of isolation, their availability and application for investigating insect-virus interactions.
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Affiliation(s)
| | - Claire L Jeffries
- Animal Health and Veterinary Laboratories Agency, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK.
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22
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Huhtamo E, Cook S, Moureau G, Uzcátegui NY, Sironen T, Kuivanen S, Putkuri N, Kurkela S, Harbach RE, Firth AE, Vapalahti O, Gould EA, de Lamballerie X. Novel flaviviruses from mosquitoes: mosquito-specific evolutionary lineages within the phylogenetic group of mosquito-borne flaviviruses. Virology 2014; 464-465:320-329. [PMID: 25108382 PMCID: PMC4170750 DOI: 10.1016/j.virol.2014.07.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 03/07/2014] [Accepted: 07/01/2014] [Indexed: 01/17/2023]
Abstract
Novel flaviviruses that are genetically related to pathogenic mosquito-borne flaviviruses (MBFV) have been isolated from mosquitoes in various geographical locations, including Finland. We isolated and characterized another novel virus of this group from Finnish mosquitoes collected in 2007, designated as Ilomantsi virus (ILOV). Unlike the MBFV that infect both vertebrates and mosquitoes, the MBFV-related viruses appear to be specific to mosquitoes similar to the insect-specific flaviviruses (ISFs). In this overview of MBFV-related viruses we conclude that they differ from the ISFs genetically and antigenically. Phylogenetic analyses separated the MBFV-related viruses isolated in Africa, the Middle East and South America from those isolated in Europe and Asia. Serological cross-reactions of MBFV-related viruses with other flaviviruses and their potential for vector-borne transmission require further characterization. The divergent MBFV-related viruses are probably significantly under sampled to date and provide new information on the variety, properties and evolution of vector-borne flaviviruses. Mosquito-borne flavivirus-related viruses were isolated from Finnish mosquitoes. Isolates were reactive with flavivirus antibodies but appeared mosquito-specific. Sequence analysis identified related viruses from different parts of the world. These viruses represent unique properties among the mosquito-borne flavivirus group.
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Affiliation(s)
- Eili Huhtamo
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Shelley Cook
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Gregory Moureau
- UMR D 190 "Emergence des Pathologies Virales", Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, 27 Boulevard Jean Moulin, Marseille 13005, France
| | - Nathalie Y Uzcátegui
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Tarja Sironen
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Suvi Kuivanen
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Niina Putkuri
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Satu Kurkela
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Virology and Immunology, Helsinki University Central Hospital Laboratory (HUSLAB), P.O. Box 400, Haartmaninkatu 3, 00029 HUS, Helsinki, Finland
| | - Ralph E Harbach
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Andrew E Firth
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
| | - Olli Vapalahti
- Department of Virology, Haartman Institute, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Virology and Immunology, Helsinki University Central Hospital Laboratory (HUSLAB), P.O. Box 400, Haartmaninkatu 3, 00029 HUS, Helsinki, Finland; Division of Microbiology and Epidemiology, Department of Basic Veterinary Sciences, University of Helsinki, Helsinki, Finland
| | - Ernest A Gould
- UMR D 190 "Emergence des Pathologies Virales", Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, 27 Boulevard Jean Moulin, Marseille 13005, France
| | - Xavier de Lamballerie
- UMR D 190 "Emergence des Pathologies Virales", Aix Marseille University, IRD French Institute of Research for Development, EHESP French School of Public Health, 27 Boulevard Jean Moulin, Marseille 13005, France
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23
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Pettersson JHO, Fiz-Palacios O. Dating the origin of the genus Flavivirus in the light of Beringian biogeography. J Gen Virol 2014; 95:1969-1982. [PMID: 24914065 DOI: 10.1099/vir.0.065227-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genus Flavivirus includes some of the most important human viral pathogens, and its members are found in all parts of the populated world. The temporal origin of diversification of the genus has long been debated due to the inherent problems with dating deep RNA virus evolution. A generally accepted hypothesis suggests that Flavivirus emerged within the last 10 000 years. However, it has been argued that the tick-borne Powassan flavivirus was introduced into North America some time between the opening and closing of the Beringian land bridge that connected Asia and North America 15 000-11 000 years ago, indicating an even older origin for Flavivirus. To determine the temporal origin of Flavivirus, we performed Bayesian relaxed molecular clock dating on a dataset with high coverage of the presently available Flavivirus diversity by combining tip date calibrations and internal node calibration, based on the Powassan virus and Beringian land bridge biogeographical event. Our analysis suggested that Flavivirus originated ~85 000 (64 000-110 000) or 120 000 (87 000-159 000) years ago, depending on the circumscription of the genus. This is significantly older than estimated previously. In light of our results, we propose that it is likely that modern humans came in contact with several members of the genus Flavivirus much earlier than suggested previously, and that it is possible that the spread of several flaviviruses coincided with, and was facilitated by, the migration and population expansion of modern humans out of Africa.
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Affiliation(s)
- John H-O Pettersson
- Department of Systematic Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Omar Fiz-Palacios
- Department of Systematic Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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24
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Ferreira DD, Cook S, Lopes Â, de Matos AP, Esteves A, Abecasis A, de Almeida APG, Piedade J, Parreira R. Characterization of an insect-specific flavivirus (OCFVPT) co-isolated from Ochlerotatus caspius collected in southern Portugal along with a putative new Negev-like virus. Virus Genes 2013; 47:532-45. [PMID: 23877720 DOI: 10.1007/s11262-013-0960-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 07/10/2013] [Indexed: 10/26/2022]
Abstract
We describe the isolation and characterization of an insect-specific flavivirus (ISF) from Ochlerotatus caspius (Pallas, 1771) mosquitoes collected in southern Portugal. The RNA genome of this virus, tentatively designated OCFVPT, for O. caspius flavivirus from Portugal, encodes a polyprotein showing all the features expected for a flavivirus. As frequently observed for ISF, the viral genomes seems to encode a putative Fairly Interesting Flavivirus ORF (FIFO)-like product, the synthesis of which would occur as a result of a -1 translation frameshift event. OCFVPT was isolated in the C6/36 Stegomyia albopicta (= Aedes albopictus) cell line where it replicates rapidly, but failed to replicate in Vero cells in common with other ISFs. Unlike some of the latter, however, the OCFVPT genome does not seem to be integrated in the mosquito cells we tested. Phylogenetic analyses based on partial ISF NS5 nucleotide sequences placed OCFVPT among recently published viral strains documented from mosquitoes collected in the Iberian Peninsula, while analyses of ORF/E/NS3/or NS5 amino acid sequences cluster OCFVPT with HANKV (Hanko virus), an ISF recently isolated from O. caspius mosquitoes collected in Finland. Taking into account the genetic relatedness with this virus, OCFVPT is not expected to be overtly cytopathic to C6/36 cells. The cytopathic effects associated with its presence in culture supernatants are postulated to be the result of the replication of a co-isolated putative new Negev-like virus.
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Affiliation(s)
- Daniela Duque Ferreira
- Unidade de Microbiologia Médica, Grupo de Virologia, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Rua da Junqueira 100, 1349-008, Lisbon, Portugal
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25
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Evangelista J, Cruz C, Guevara C, Astete H, Carey C, Kochel TJ, Morrison AC, Williams M, Halsey ES, Forshey BM. Characterization of a novel flavivirus isolated from Culex (Melanoconion) ocossa mosquitoes from Iquitos, Peru. J Gen Virol 2013; 94:1266-1272. [DOI: 10.1099/vir.0.050575-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We describe the isolation and characterization of a novel flavivirus, isolated from a pool of Culex (Melanoconion) ocossa Dyar and Knab mosquitoes collected in 2009 in an urban area of the Amazon basin city of Iquitos, Peru. Flavivirus infection was detected by indirect immunofluorescent assay of inoculated C6/36 cells using polyclonal flavivirus antibodies (St. Louis encephalitis virus, yellow fever virus and dengue virus type 1) and confirmed by RT-PCR. Based on partial sequencing of the E and NS5 gene regions, the virus isolate was most closely related to the mosquito-borne flaviviruses but divergent from known species, with less than 45 and 71 % pairwise amino acid identity in the E and NS5 gene products, respectively. Phylogenetic analysis of E and NS5 amino acid sequences demonstrated that this flavivirus grouped with mosquito-borne flaviviruses, forming a clade with Nounané virus (NOUV). Like NOUV, no replication was detected in a variety of mammalian cells (Vero-76, Vero-E6, BHK, LLCMK, MDCK, A549 and RD) or in intracerebrally inoculated newborn mice. We tentatively designate this genetically distinct flavivirus as representing a novel species, Nanay virus, after the river near where it was first detected.
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Affiliation(s)
- Julio Evangelista
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Cristhopher Cruz
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Carolina Guevara
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Helvio Astete
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Cristiam Carey
- Dirección Regional de Salud de Loreto, Av 28 de Julio, Punchana, Loreto, Peru
| | - Tadeusz J. Kochel
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Amy C. Morrison
- Department of Entomology, University of California, One Shields Avenue, Davis, CA 95616, USA
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Maya Williams
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Eric S. Halsey
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
| | - Brett M. Forshey
- Virology Department, U.S. Naval Medical Research Unit No. 6, Lima and Iquitos, Peru
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26
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Tumban E, Maes NE, Schirtzinger EE, Young KI, Hanson CT, Whitehead SS, Hanley KA. Replacement of conserved or variable sequences of the mosquito-borne dengue virus 3' UTR with homologous sequences from Modoc virus does not change infectivity for mosquitoes. J Gen Virol 2012; 94:783-788. [PMID: 23255623 DOI: 10.1099/vir.0.046664-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The genus Flavivirus includes both vector-borne and no known vector (NKV) species, but the molecular determinants of transmission mode are not known. Conserved sequence differences between the two groups occur in 5' and 3' UTRs. To investigate the impact of these differences on transmission, chimeric genomes were generated, in which UTRs, UTRs+capsid, or the upper 3' UTR stem-loop of mosquito-borne dengue virus (DENV) were replaced with homologous regions from NKV Modoc virus (MODV); the conserved pentanucleotide sequence (CPS) was also deleted from the DENV genome. Virus was not recovered following transfection of these genomes in three different cell types. However, DENV genomes in which the CPS or variable region (VR) of the 3' UTR were replaced with MODV sequences were recovered and infected Aedes aegypti mosquitoes with similar efficiencies to DENV. These results demonstrate that neither vector-borne CPS nor VR is required for vector-borne transmission.
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Affiliation(s)
- Ebenezer Tumban
- Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA.,Molecular Biology Program, New Mexico State University, Las Cruces, NM 88003, USA
| | - Nyree E Maes
- Molecular Biology Program, New Mexico State University, Las Cruces, NM 88003, USA
| | - Erin E Schirtzinger
- Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Katherine I Young
- Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Christopher T Hanson
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephen S Whitehead
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kathryn A Hanley
- Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA.,Molecular Biology Program, New Mexico State University, Las Cruces, NM 88003, USA
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27
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Replication of West Nile virus, Rabensburg lineage in mammalian cells is restricted by temperature. Parasit Vectors 2012; 5:293. [PMID: 23241081 PMCID: PMC3534007 DOI: 10.1186/1756-3305-5-293] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 12/11/2012] [Indexed: 11/10/2022] Open
Abstract
Background The genus Flavivirus currently consists of approximately 80 single-strand positive-sense RNA viruses. These replicate in a range of hosts including myriad vertebrate, insect, and tick species. As a consequence of this broad host range, the majority of flaviviruses can be propagated in most vertebrate and insect cell cultures. This ability to infect arthropods and vertebrates usually is essential for maintenance of these viruses in nature. But recently, there has been the discovery of a number of flaviviruses that infect mosquitoes but not vertebrates. It remains largely unknown why certain flaviviruses infect vertebrates and mosquitoes while others infect mosquitoes or vertebrates exclusively. Methods Here, we initiated in vitro host range studies of Rabensburg virus (RABV), an intermediate between the mosquito-specific and horizontally transmitted flaviviruses, to provide information on the factor(s) that underlie the varying host range of flaviviruses. RABV is an intermediate between the mosquito-specific and horizontally transmitted flaviviruses because it does not infect mammalian or avian cell cultures, house sparrows, or chickens, but it does share genetic characteristics with the Japanese Encephalitis serogroup of flaviviruses. Results In vitro growth kinetic assays revealed the complete abrogation of RABV growth on Vero and E6 cells incubated at temperatures 35°C and higher, but surprisingly RABV infected, replicated efficiently, and displayed overt cytopathic effects (CPE) on Vero and E6 cell cultures incubated below 35°C. In contrast, RABV was fully viable, replicated efficiently, and displayed overt CPE on C6/36 cells incubated at 28°C or 37°C, thus implicating temperature as an important factor limiting the host range of RABV. Conclusions These data are critical for further study to more fully identify the determinants that mediate the evolution of biological transmission among flaviviruses. It also will be useful for studies that look to provide a comprehensive molecular definition of flavivirus-host cell interactions. And it will provide a cadre of information to design wet lab experiments to investigate the genetic changes that facilitate host switching, which may lead to new vertebrate pathogens or transmission pathways.
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28
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Huhtamo E, Moureau G, Cook S, Julkunen O, Putkuri N, Kurkela S, Uzcátegui NY, Harbach RE, Gould EA, Vapalahti O, de Lamballerie X. Novel insect-specific flavivirus isolated from northern Europe. Virology 2012; 433:471-8. [PMID: 22999256 PMCID: PMC3919202 DOI: 10.1016/j.virol.2012.08.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 06/18/2012] [Accepted: 08/20/2012] [Indexed: 11/29/2022]
Abstract
Mosquitoes collected in Finland were screened for flaviviral RNA leading to the discovery and isolation of a novel flavivirus designated Hanko virus (HANKV). Virus characterization, including phylogenetic analysis of the complete coding sequence, confirmed HANKV as a member of the “insect-specific” flavivirus (ISF) group. HANKV is the first member of this group isolated from northern Europe, and therefore the first northern European ISF for which the complete coding sequence has been determined. HANKV was not transcribed as DNA in mosquito cell culture, which appears atypical for an ISF. HANKV shared highest sequence homology with the partial NS5 sequence available for the recently discovered Spanish Ochlerotatus flavivirus (SOcFV). Retrospective analysis of mitochondrial sequences from the virus-positive mosquito pool suggested an Ochlerotatus mosquito species as the most likely host for HANKV. HANKV and SOcFV may therefore represent a novel group of Ochlerotatus-hosted insect-specific flaviviruses in Europe and further afield.
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Affiliation(s)
- Eili Huhtamo
- Infection Biology Research Program, Research Programs Unit, Department of Virology, Haartman Institute, University of Helsinki, Helsinki FIN-00014, Finland.
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29
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Kuno G. Comment on: Successful propagation of Alkhumra (misnamed as Alkhurma) virus in C6/36 mosquito cells. Trans R Soc Trop Med Hyg 2012; 106:392; author reply 392-3. [PMID: 22579559 DOI: 10.1016/j.trstmh.2012.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 03/16/2012] [Indexed: 10/28/2022] Open
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30
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Parreira R, Cook S, Lopes Â, de Matos AP, de Almeida APG, Piedade J, Esteves A. Genetic characterization of an insect-specific flavivirus isolated from Culex theileri mosquitoes collected in southern Portugal. Virus Res 2012; 167:152-61. [PMID: 22579596 PMCID: PMC3919203 DOI: 10.1016/j.virusres.2012.04.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 03/30/2012] [Accepted: 04/11/2012] [Indexed: 12/04/2022]
Abstract
We describe the full genetic characterization of an insect-specific flavivirus (ISF) from Culex theileri (Theobald) mosquitoes collected in Portugal. This represents the first isolation and full characterization of an ISF from Portuguese mosquitoes. The virus, designated CTFV, for Culex theileri flavivirus, was isolated in the C6/36 Stegomyia albopicta (=Aedes albopictus) cell line, and failed to replicate in vertebrate (Vero) cells in common with other ISFs. The CTFV genome encodes a single polyprotein with 3357 residues showing all the features expected for those of flaviviruses. Phylogenetic analyses based on all ISF sequences available to date, place CTFV among Culex-associated flaviviruses, grouping with recently published NS5 partial sequences documented from mosquitoes collected in the Iberian Peninsula, and with Quang Binh virus (isolated in Vietnam) as a close relative. No CTFV sequences were found integrated in their host's genome using a range of specific PCR primers designed to the prM/E, NS3, and NS5 region.
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Affiliation(s)
- Ricardo Parreira
- Unidade de Microbiologia Médica, Grupo de Virologia, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira 100, 1349-008 Lisboa, Portugal.
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31
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Cook S, Moureau G, Kitchen A, Gould EA, de Lamballerie X, Holmes EC, Harbach RE. Molecular evolution of the insect-specific flaviviruses. J Gen Virol 2011; 93:223-234. [PMID: 22012464 PMCID: PMC3352342 DOI: 10.1099/vir.0.036525-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
There has been an explosion in the discovery of ‘insect-specific’ flaviviruses and/or their related sequences in natural mosquito populations. Herein we review all ‘insect-specific’ flavivirus sequences currently available and conduct phylogenetic analyses of both the ‘insect-specific’ flaviviruses and available sequences of the entire genus Flavivirus. We show that there is no statistical support for virus–mosquito co-divergence, suggesting that the ‘insect-specific’ flaviviruses may have undergone multiple introductions with frequent host switching. We discuss potential implications for the evolution of vectoring within the family Flaviviridae. We also provide preliminary evidence for potential recombination events in the history of cell fusing agent virus. Finally, we consider priorities and guidelines for future research on ‘insect-specific’ flaviviruses, including the vast potential that exists for the study of biodiversity within a range of potential hosts and vectors, and its effect on the emergence and maintenance of the flaviviruses.
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Affiliation(s)
- Shelley Cook
- Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Gregory Moureau
- Unité des Virus Emergents UMR190, Université de la Méditerranée, Institut de Recherche pour le Développement, EHESP French School of Public Health, Marseille, France
| | - Andrew Kitchen
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Ernest A Gould
- Centre for Ecology and Hydrology, Wallingford, Oxfordshire OX10 8BB, UK.,Unité des Virus Emergents UMR190, Université de la Méditerranée, Institut de Recherche pour le Développement, EHESP French School of Public Health, Marseille, France
| | - Xavier de Lamballerie
- Unité des Virus Emergents UMR190, Université de la Méditerranée, Institut de Recherche pour le Développement, EHESP French School of Public Health, Marseille, France
| | - Edward C Holmes
- Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA.,Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
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32
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Engel AR, Mitzel DN, Hanson CT, Wolfinbarger JB, Bloom ME, Pletnev AG. Chimeric tick-borne encephalitis/dengue virus is attenuated in Ixodes scapularis ticks and Aedes aegypti mosquitoes. Vector Borne Zoonotic Dis 2010; 11:665-74. [PMID: 21142950 DOI: 10.1089/vbz.2010.0179] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In an effort to derive an efficacious live attenuated vaccine against tick-borne encephalitis, we generated a chimeric virus bearing the structural protein genes of a Far Eastern subtype of tick-borne encephalitis virus (TBEV) on the genetic background of recombinant dengue 4 (DEN4) virus. Introduction of attenuating mutations into the TBEV envelope protein gene, as well as the DEN4 NS5 protein gene and 3' noncoding region in the chimeric genome, results in decreased neurovirulence and neuroinvasiveness in mice, and restricted replication in mouse brain. Since TBEV and DEN4 viruses are transmitted in nature by ticks and mosquitoes, respectively, it was of interest to investigate the infectivity of the chimeric virus for both arthropod vectors. Therefore, parental and chimeric viruses were tested for growth in mosquito and tick cells and for oral infection in vivo. Although all chimeric viruses demonstrated moderate levels of replication in C6/36 mosquito cells, they were unable to replicate in ISE6 tick cells. Further, the chimeric viruses were unable to infect or replicate in Aedes aegypti mosquitoes and Ixodes scapularis tick larvae. The poor infectivity for both potential vectors reinforces the safety of chimeric virus-based vaccine candidates for the environment and for use in humans.
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Affiliation(s)
- Amber R Engel
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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33
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Ebel GD. Update on Powassan virus: emergence of a North American tick-borne flavivirus. ANNUAL REVIEW OF ENTOMOLOGY 2010; 55:95-110. [PMID: 19961325 DOI: 10.1146/annurev-ento-112408-085446] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Powassan virus (POW) (Flaviviridae: Flavivirus) is the cause of rare but severe neuroinvasive disease in North America and Russia. The virus is transmitted among small- and medium-sized mammals by ixodid ticks. Human infections occur via spillover from the main transmission cycle(s). Since the late 1990s, the incidence of human disease seems to be increasing. In addition, POW constitutes a genetically diverse group of virus genotypes, including Deer tick virus, that are maintained in distinct enzootic transmission cycles. This review highlights recent research into POW, focusing on virus genetics and ecology and human disease. Important directions for future research are also discussed.
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Affiliation(s)
- Gregory D Ebel
- Department of Pathology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA.
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34
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Danecek P, Lu W, Schein CH. PCP consensus sequences of flaviviruses: correlating variance with vector competence and disease phenotype. J Mol Biol 2009; 396:550-63. [PMID: 19969003 DOI: 10.1016/j.jmb.2009.11.070] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Revised: 11/18/2009] [Accepted: 11/30/2009] [Indexed: 01/11/2023]
Abstract
BACKGROUND Computational methods are needed to design multivalent vaccines against flaviviruses (FVs) such as the West Nile virus or the dengue virus (DENV). OBJECTIVE We aimed to use physicochemical property (PCP) consensus sequences of FV strains to delineate conserved motifs, areas of maximum variability, and specific loci that correlate with arthropod vector, serotype, and disease severity. METHODS PCP consensus sequences for 27 species were prepared from 928 annotated sequences catalogued in Flavitrack. Alignments of these correlated well with the known structures of the NS3 protease domain and envelope (E) proteins. The PCPMer suite was used to identify motifs common to all FVs. Areas of PCP variability that correlated with phenotype were plotted on the structures. RESULTS Despite considerable diversity at the amino acid level, PCPs for both proteins were well conserved throughout the FVs. A series of insertions in E separated tick- from mosquito-borne viruses and all arthropod-borne viruses from isolates with no known vector or directly from insects. Comparison of a PCP consensus sequence of E derived from 600 DENV strains (DENV600) with individual ones for DENV1-DENV4 showed that most major serotype-specific variation occurs near these insertions. The DENV600 differed from one prepared from eight hemorrhagic or fatal strains from four DENV serotypes at only three positions, two of which overlap known escape mutant sites. CONCLUSIONS Comparing consensus sequences showed that substantial changes occur in only a few areas of the E protein. PCP consensus sequences can contribute to the design of multivalent vaccines.
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Affiliation(s)
- Petr Danecek
- Sealy Center for Structural Biology and Molecular Biophysics, Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0857, USA
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35
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Cook S, Moureau G, Harbach RE, Mukwaya L, Goodger K, Ssenfuka F, Gould E, Holmes EC, de Lamballerie X. Isolation of a novel species of flavivirus and a new strain of Culex flavivirus (Flaviviridae) from a natural mosquito population in Uganda. J Gen Virol 2009; 90:2669-2678. [PMID: 19656970 PMCID: PMC2885038 DOI: 10.1099/vir.0.014183-0] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 07/30/2009] [Indexed: 11/18/2022] Open
Abstract
The genus Flavivirus, which contains approximately 70 single-stranded, positive-sense RNA viruses, represents a unique model for studying the evolution of vector-borne disease, as it includes viruses that are mosquito-borne, tick-borne or have no known vector. Both theoretical work and field studies suggest the existence of a large number of undiscovered flaviviruses. Recently, the first isolation of cell fusing agent virus (CFAV) was reported from a natural mosquito population in Puerto Rico, and sequences related to CFAV have been discovered in mosquitoes from Thailand. CFAV had previously been isolated from a mosquito cell line in 1975 and represented the only known 'insect-only' flavivirus, appearing to replicate in insect cells alone. A second member of the 'insect-only' group, Kamiti River virus (KRV), was isolated from Kenyan mosquitoes in 2003. A third tentative member of the 'insect-only' group, Culex flavivirus (CxFV), was first isolated in 2007 from Japan and further strains have subsequently been reported from the Americas. We report the discovery, isolation and characterization of two novel 'insect-only' flaviviruses from Entebbe, Uganda: a novel lineage tentatively designated Nakiwogo virus (NAKV) and a new strain of CxFV. The individual mosquitoes from which these strains were isolated, identified retrospectively by using a reference molecular phylogeny generated using voucher specimens from the region, were Mansonia africana nigerrima and Culex quinquefasciatus, respectively. This represents the first isolation, to our knowledge, of a novel insect-only flavivirus from a Mansonia species and the first isolation of a strain of CxFV from Africa.
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Affiliation(s)
- Shelley Cook
- Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Gregory Moureau
- Unité des Virus Emergents UMR190 ‘Emergence des Pathologies Virales’, Université de la Méditerranée et Institut de Recherche pour le Développement, Marseille, France
| | | | - Louis Mukwaya
- Mosquito Research Programme, Uganda Virus Research Institute, PO Box 49, Entebbe, Uganda
| | - Kim Goodger
- Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Fred Ssenfuka
- Mosquito Research Programme, Uganda Virus Research Institute, PO Box 49, Entebbe, Uganda
| | - Ernest Gould
- Unité des Virus Emergents UMR190 ‘Emergence des Pathologies Virales’, Université de la Méditerranée et Institut de Recherche pour le Développement, Marseille, France
- Centre for Ecology and Hydrology Oxford, Mansfield Road, Oxford OX1 3SR, UK
| | - Edward C. Holmes
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Xavier de Lamballerie
- Unité des Virus Emergents UMR190 ‘Emergence des Pathologies Virales’, Université de la Méditerranée et Institut de Recherche pour le Développement, Marseille, France
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Huhtamo E, Putkuri N, Kurkela S, Manni T, Vaheri A, Vapalahti O, Uzcátegui NY. Characterization of a novel flavivirus from mosquitoes in northern europe that is related to mosquito-borne flaviviruses of the tropics. J Virol 2009; 83:9532-40. [PMID: 19570865 PMCID: PMC2738272 DOI: 10.1128/jvi.00529-09] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Accepted: 06/22/2009] [Indexed: 11/20/2022] Open
Abstract
A novel flavivirus was isolated from mosquitoes in Finland, representing the first mosquito-borne flavivirus from Northern Europe. The isolate, designated Lammi virus (LAMV), was antigenically cross-reactive with other flaviviruses and exhibited typical flavivirus morphology as determined by electron microscopy. The genomic sequence of LAMV was highly divergent from the recognized flaviviruses, and yet the polyprotein properties resembled those of mosquito-borne flaviviruses. Phylogenetic analysis of the complete coding sequence showed that LAMV represented a distinct lineage related to the Aedes sp.-transmitted human pathogenic flaviviruses, similarly to the newly described Nounané virus (NOUV), a flavivirus from Africa (S. Junglen et al., J. Virol. 83:4462-4468, 2009). Despite the low sequence homology, LAMV and NOUV were phylogenetically grouped closely, likely representing separate species of a novel group of flaviviruses. Despite the biological properties preferring replication in mosquito cells, the genetic relatedness of LAMV to viruses associated with vertebrate hosts warrants a search for disease associations.
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Affiliation(s)
- Eili Huhtamo
- Department of Virology, Haartman Institute, University of Helsinki, Finland.
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Lobo FP, Mota BEF, Pena SDJ, Azevedo V, Macedo AM, Tauch A, Machado CR, Franco GR. Virus-host coevolution: common patterns of nucleotide motif usage in Flaviviridae and their hosts. PLoS One 2009; 4:e6282. [PMID: 19617912 PMCID: PMC2707012 DOI: 10.1371/journal.pone.0006282] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Accepted: 06/17/2009] [Indexed: 12/18/2022] Open
Abstract
Virus-host biological interaction is a continuous coevolutionary process involving both host immune system and viral escape mechanisms. Flaviviridae family is composed of fast evolving RNA viruses that infects vertebrate (mammals and birds) and/or invertebrate (ticks and mosquitoes) organisms. These host groups are very distinct life forms separated by a long evolutionary time, so lineage-specific anti-viral mechanisms are likely to have evolved. Flaviviridae viruses which infect a single host lineage would be subjected to specific host-induced pressures and, therefore, selected by them. In this work we compare the genomic evolutionary patterns of Flaviviridae viruses and their hosts in an attempt to uncover coevolutionary processes inducing common features in such disparate groups. Especially, we have analyzed dinucleotide and codon usage patterns in the coding regions of vertebrate and invertebrate organisms as well as in Flaviviridae viruses which specifically infect one or both host types. The two host groups posses very distinctive dinucleotide and codon usage patterns. A pronounced CpG under-representation was found in the vertebrate group, possibly induced by the methylation-deamination process, as well as a prominent TpA decrease. The invertebrate group displayed only a TpA frequency reduction bias. Flaviviridae viruses mimicked host nucleotide motif usage in a host-specific manner. Vertebrate-infecting viruses possessed under-representation of CpG and TpA, and insect-only viruses displayed only a TpA under-representation bias. Single-host Flaviviridae members which persistently infect mammals or insect hosts (Hepacivirus and insect-only Flavivirus, respectively) were found to posses a codon usage profile more similar to that of their hosts than to related Flaviviridae. We demonstrated that vertebrates and mosquitoes genomes are under very distinct lineage-specific constraints, and Flaviviridae viruses which specifically infect these lineages appear to be subject to the same evolutionary pressures that shaped their host coding regions, evidencing the lineage-specific coevolutionary processes between the viral and host groups.
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Affiliation(s)
- Francisco P Lobo
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
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