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Jain S, Vimal N, Angmo N, Sengupta M, Thangaraj S. Dengue Vaccination: Towards a New Dawn of Curbing Dengue Infection. Immunol Invest 2023; 52:1096-1149. [PMID: 37962036 DOI: 10.1080/08820139.2023.2280698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Dengue is an infectious disease caused by dengue virus (DENV) and is a serious global burden. Antibody-dependent enhancement and the ability of DENV to infect immune cells, along with other factors, lead to fatal Dengue Haemorrhagic Fever and Dengue Shock Syndrome. This necessitates the development of a robust and efficient vaccine but vaccine development faces a number of hurdles. In this review, we look at the epidemiology, genome structure and cellular targets of DENV and elaborate upon the immune responses generated by human immune system against DENV infection. The review further sheds light on various challenges in development of a potent vaccine against DENV which is followed by presenting a current account of different vaccines which are being developed or have been licensed.
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Affiliation(s)
- Sidhant Jain
- Independent Researcher, Institute for Globally Distributed Open Research and Education (IGDORE), Rewari, India
| | - Neha Vimal
- Bhaskaracharya College of Applied Sciences, University of Delhi, Delhi, India
| | - Nilza Angmo
- Maitreyi College, University of Delhi, Delhi, India
| | - Madhumita Sengupta
- Janki Devi Bajaj Government Girls College, University of Kota, Kota, India
| | - Suraj Thangaraj
- Swami Ramanand Teerth Rural Government Medical College, Maharashtra University of Health Sciences, Ambajogai, India
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2
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Mao L, He Y, Wu Z, Wang X, Guo J, Zhang S, Wang M, Jia R, Zhu D, Liu M, Zhao X, Yang Q, Mao S, Wu Y, Zhang S, Huang J, Ou X, Gao Q, Sun D, Cheng A, Chen S. Stem-Loop I of the Tembusu Virus 3'-Untranslated Region Is Responsible for Viral Host-Specific Adaptation and the Pathogenicity of the Virus in Mice. Microbiol Spectr 2022; 10:e0244922. [PMID: 36214697 PMCID: PMC9602528 DOI: 10.1128/spectrum.02449-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 09/17/2022] [Indexed: 01/04/2023] Open
Abstract
Tembusu virus (TMUV), an avian mosquito-borne flavivirus, was first identified from Culex tritaeniorhynchus in 1955. To validate the effects of the 3'-untranslated region (3'UTR) in viral host-specific adaptation, we generated a set of chimeric viruses using CQW1 (duck strain) and MM 1775 (mosquito strain) as backbones with heterogeneous 3'UTRs. Compared with rMM 1775, rMM-CQ3'UTR (recombinant MM 1775 virus carrying the 3'UTR of CQW1) exhibited enhanced proliferation in vitro, with peak titers increasing by 5-fold in duck embryonic fibroblast (DEF) cells or 12-fold in baby hamster kidney (BHK-21) cells; however, the neurovirulence of rMM-CQ3'UTR was attenuated in 14-day-old Kunming mice via intracranial injection, with slower weight loss, lower mortality, and reduced viral loads. In contrast, rCQ-MM3'UTR showed similar growth kinetics in vitro and neurovirulence in mice compared with those of rCQW1. Then, the Stem-loop I (SLI) structure, which showed the highest variation within the 3'UTR between CQW1 and MM 1775, was further chosen for making chimeric viruses. The peak titers of rMM-CQ3'UTRSLI displayed a 15- or 4-fold increase in vitro, and the neurovirulence in mice was attenuated, compared with that of rMM 1775; rCQ-MM3'UTRSLI displayed comparable multiplication ability in vitro but was significantly attenuated in mice, in contrast with rCQW1. In conclusion, we demonstrated that the TMUV SLI structure of the 3'UTR was responsible for viral host-specific adaptation of the mosquito-derived strain in DEF and BHK-21 cells and regulated viral pathogenicity in 14-day-old mice, providing a new understanding of the functions of TMUV 3'UTR in viral host switching and the pathogenicity changes in mice. IMPORTANCE Mosquito-borne flaviviruses (MBFVs) constitute a large number of mosquito-transmitted viruses. The 3'-untranslated region (3'UTR) of MBFV has been suggested to be relevant to viral host-specific adaptation. However, the evolutionary strategies for host-specific fitness among MBFV are different, and the virulence-related structures within the 3'UTR are largely unknown. Here, using Tembusu virus (TMUV), an avian MBFV as models, we observed that the duck-derived SLI of the 3'UTR significantly enhanced the proliferation ability of mosquito-derived TMUV in baby hamster kidney (BHK-21) and duck embryonic fibroblast (DEF) cells, suggesting that the SLI structure was crucial for viral host-specific adaptation of mosquito-derived TMUVs in mammalian and avian cells. In addition, all SLI mutant viruses exhibited reduced viral pathogenicity in mice, indicating that SLI structure was a key factor for the pathogenicity in mice. This study provides a new insight into the functions of the MBFV 3'UTR in viral host switching and pathogenicity changes in mice.
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Affiliation(s)
- Li Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yu He
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Zhen Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xiaoli Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Jiaqi Guo
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Senzhao Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Dekang Zhu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xinxin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
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3
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de Oliveira Ribeiro G, da Costa AC, Gill DE, Ribeiro ESD, Rego MODS, Monteiro FJC, Villanova F, Nogueira JS, Maeda AY, de Souza RP, Tahmasebi R, Morais VS, Pandey RP, Raj VS, Scandar SAS, da Silva Vasami FG, D'Agostino LG, Maiorka PC, Deng X, Nogueira ML, Sabino EC, Delwart E, Leal É, Cunha MS. Guapiaçu virus, a new insect-specific flavivirus isolated from two species of Aedes mosquitoes from Brazil. Sci Rep 2021; 11:4674. [PMID: 33633167 PMCID: PMC7907106 DOI: 10.1038/s41598-021-83879-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 02/03/2021] [Indexed: 12/18/2022] Open
Abstract
Classical insect-flaviviruses (cISFVs) and dual host-related insect-specific flavivirus (dISFV) are within the major group of insect-specific flavivirus. Remarkably dISFV are evolutionarily related to some of the pathogenic flavivirus, such as Zika and dengue viruses. The Evolutionary relatedness of dISFV to flavivirus allowed us to investigate the evolutionary principle of host adaptation. Additionally, dISFV can be used for the development of flavivirus vaccines and to explore underlying principles of mammalian pathogenicity. Here we describe the genetic characterization of a novel putative dISFV, termed Guapiaçu virus (GUAPV). Distinct strains of GUAPV were isolated from pools of Aedes terrens and Aedes scapularis mosquitoes. Additionally, we also detected viral GUAPV RNA in a plasma sample of an individual febrile from the Amazon region (North of Brazil). Although GUAPV did not replicate in tested mammalian cells, 3′UTR secondary structures duplication and codon usage index were similar to pathogenic flavivirus.
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Affiliation(s)
| | | | - Danielle Elise Gill
- Institute of Tropical Medicine, University of São Paulo, São Paulo, SP, 05403-000, Brazil
| | - Edcelha Soares D'Athaide Ribeiro
- Public Health Laboratory of Amapa-LACEN/AP, Health Surveillance Superintendence of Amapa, Rua Tancredo Neves, 1.118, Macapá, AP, CEP 68905-230, Brazil
| | - Marlisson Octavio da S Rego
- Public Health Laboratory of Amapa-LACEN/AP, Health Surveillance Superintendence of Amapa, Rua Tancredo Neves, 1.118, Macapá, AP, CEP 68905-230, Brazil
| | - Fred Julio Costa Monteiro
- Public Health Laboratory of Amapa-LACEN/AP, Health Surveillance Superintendence of Amapa, Rua Tancredo Neves, 1.118, Macapá, AP, CEP 68905-230, Brazil
| | - Fabiola Villanova
- Institute of Biological Sciences, Federal University of Pará, Belém, Pará, 66075-000, Brazil
| | - Juliana Silva Nogueira
- Vector-Borne Diseases Laboratory, Virology Center, Adolfo Lutz Institute, São Paulo, SP, 01246-000, Brazil
| | - Adriana Yurika Maeda
- Vector-Borne Diseases Laboratory, Virology Center, Adolfo Lutz Institute, São Paulo, SP, 01246-000, Brazil
| | - Renato Pereira de Souza
- Vector-Borne Diseases Laboratory, Virology Center, Adolfo Lutz Institute, São Paulo, SP, 01246-000, Brazil
| | - Roozbeh Tahmasebi
- Institute of Tropical Medicine, University of São Paulo, São Paulo, SP, 05403-000, Brazil
| | - Vanessa S Morais
- Institute of Tropical Medicine, University of São Paulo, São Paulo, SP, 05403-000, Brazil
| | - Ramendra Pati Pandey
- Centre for Drug Design Discovery and Development (C4D), SRM University, Delhi-NCR, Rajiv Gandhi Education City, Sonepat, Haryana, India
| | - V Samuel Raj
- Centre for Drug Design Discovery and Development (C4D), SRM University, Delhi-NCR, Rajiv Gandhi Education City, Sonepat, Haryana, India
| | | | | | | | - Paulo César Maiorka
- Department of Pathology, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Xutao Deng
- Vitalant Research Institute, 270 Masonic Avenue, San Francisco, CA, 94118-4417, USA.,Department Laboratory Medicine, University of California San Francisco, San Francisco, CA, 94143, USA
| | | | - Ester Cerdeira Sabino
- Institute of Tropical Medicine, University of São Paulo, São Paulo, SP, 05403-000, Brazil
| | - Eric Delwart
- Vitalant Research Institute, 270 Masonic Avenue, San Francisco, CA, 94118-4417, USA. .,Department Laboratory Medicine, University of California San Francisco, San Francisco, CA, 94143, USA.
| | - Élcio Leal
- Institute of Biological Sciences, Federal University of Pará, Belém, Pará, 66075-000, Brazil.
| | - Mariana Sequetin Cunha
- Institute of Tropical Medicine, University of São Paulo, São Paulo, SP, 05403-000, Brazil. .,Vector-Borne Diseases Laboratory, Virology Center, Adolfo Lutz Institute, São Paulo, SP, 01246-000, Brazil.
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4
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Cerikan B, Goellner S, Neufeldt CJ, Haselmann U, Mulder K, Chatel-Chaix L, Cortese M, Bartenschlager R. A Non-Replicative Role of the 3' Terminal Sequence of the Dengue Virus Genome in Membranous Replication Organelle Formation. Cell Rep 2020; 32:107859. [PMID: 32640225 PMCID: PMC7351112 DOI: 10.1016/j.celrep.2020.107859] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 04/11/2020] [Accepted: 06/12/2020] [Indexed: 12/14/2022] Open
Abstract
Dengue virus (DENV) and Zika virus (ZIKV), members of the Flavivirus genus, rearrange endoplasmic reticulum membranes to induce invaginations known as vesicle packets (VPs), which are the assumed sites for viral RNA replication. Mechanistic information on VP biogenesis has so far been difficult to attain due to the necessity of studying their formation under conditions of viral replication, where perturbations reducing replication will inevitably impact VP formation. Here, we report a replication-independent expression system, designated pIRO (plasmid-induced replication organelle formation) that induces bona fide DENV and ZIKV VPs that are morphologically indistinguishable from those in infected cells. Using this system, we demonstrate that sequences in the 3' terminal RNA region of the DENV, but not the ZIKV genome, contribute to VP formation in a non-replicative manner. These results validate the pIRO system that opens avenues for mechanistically dissecting virus replication from membrane reorganization.
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Affiliation(s)
- Berati Cerikan
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Sarah Goellner
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Christopher John Neufeldt
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Uta Haselmann
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Klaas Mulder
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Laurent Chatel-Chaix
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Mirko Cortese
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg Partner Site, University, 69120 Heidelberg, Germany.
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5
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Zeng M, Duan Y, Zhang W, Wang M, Jia R, Zhu D, Liu M, Zhao X, Yang Q, Wu Y, Zhang S, Liu Y, Zhang L, Yu Y, Chen S, Cheng A. Universal RNA Secondary Structure Insight Into Mosquito-Borne Flavivirus (MBFV) cis-Acting RNA Biology. Front Microbiol 2020; 11:473. [PMID: 32292394 PMCID: PMC7118588 DOI: 10.3389/fmicb.2020.00473] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 03/04/2020] [Indexed: 12/22/2022] Open
Abstract
Mosquito-borne flaviviruses (MBFVs) spread between vertebrate (mammals and birds) and invertebrate (mosquitoes) hosts. The cis-acting RNAs of MBFV share common evolutionary origins and contain frequent alterations, which control the balance of linear and circular genome conformations and allow effective replication. Importantly, multiple cis-acting RNAs interact with trans-acting regulatory RNA-binding proteins (RBPs) and affect the MBFV lifecycle process, including viral replicase binding, viral RNA translation-cyclisation-synthesis and nucleocapsid assembly. Considering that extensive structural probing analyses have been performed on MBFV cis-acting RNAs, herein the homologous RNA structures are online folded and consensus structures are constructed by sort. The specific traits and underlying biology of MBFV cis-acting RNA are illuminated accordingly in a review of RNA structure. These findings deepen our understanding of MBFV cis-acting RNA biology and serve as a resource for designing therapeutics in targeting protein-viral RNA interaction or viral RNA secondary structures.
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Affiliation(s)
- Miao Zeng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yanping Duan
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Wei Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Dekang Zhu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Mafeng Liu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Xinxin Zhao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Qiao Yang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Ying Wu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Shaqiu Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Yunya Liu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ling Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yangling Yu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shun Chen
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
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6
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Ternovoi VA, Gladysheva AV, Ponomareva EP, Mikryukova TP, Protopopova EV, Shvalov AN, Konovalova SN, Chausov EV, Loktev VB. Variability in the 3' untranslated regions of the genomes of the different tick-borne encephalitis virus subtypes. Virus Genes 2019; 55:448-457. [PMID: 31111398 DOI: 10.1007/s11262-019-01672-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 05/14/2019] [Indexed: 12/21/2022]
Abstract
Tick-borne encephalitis viruses (TBEVs) are usually divided into three major subtypes: European (TBEV-Eu), Siberian (TBEV-Sib) and Far Eastern (TBEV-FE). The TBEV-Eu strains have the longest genomes, and TBEV-FE strains have the smallest genomes. Changes in the variable region of the untranslated region (V3' UTR) play a major role in determining the viral genome length. Analyses of the 3' UTRs of the different subtypes of TBEV have revealed significant changes in the secondary structures of the V3' UTR of TBEV. More complex secondary structures of the V3' UTR regions are typical for TBEV-Eu. The Siberian strain Tomsk-PT122 was isolated from birds and has an unusual 3' UTR. Several short fragment (24-26 nucleotides) insertions derived from the viral E (2) and NS4a (1) genes have been found in the V3' UTR of Tomsk-PT122. Additionally, the length of the V3' UTR increases from 21 to 37 nucleotides during passages of the C11-13 strain of TBEV-Sib into PEK, 293 and Neuro-2a cells. The elongation of the V3' UTRs of Tomsk-PT122 and C11-13 is the first direct evidence of an intragenomic 3' UTR modification (insertion) for TBEV. Thus, the obtained results suggest that changing the length of the V3' UTR in the genome is typical for different TBEV subtypes and can play an essential role in effective TBEV replication in different host cells.
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Affiliation(s)
- Vladimir A Ternovoi
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Anastasia V Gladysheva
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
- Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Eugenia P Ponomareva
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Tamara P Mikryukova
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Elena V Protopopova
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Alexander N Shvalov
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Svetlana N Konovalova
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Eugene V Chausov
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia
| | - Valery B Loktev
- Department of Molecular Virology for Flaviviruses and Viral Hepatitis, State Research Center for Virology and Biotechnology "Vector", Koltsovo, Novosibirsk Region, 630559, Russia.
- Novosibirsk State University, Novosibirsk, 630090, Russia.
- Institute of Cytology and Genetics, Novosibirsk, 630090, Russia.
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7
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Abstract
Flaviviruses include a diverse group of medically important viruses that cycle between mosquitoes and humans. During this natural process of switching hosts, each species imposes different selective forces on the viral population. Using dengue virus (DENV) as model, we found that paralogous RNA structures originating from duplications in the viral 3' untranslated region (UTR) are under different selective pressures in the two hosts. These RNA structures, known as dumbbells (DB1 and DB2), were originally proposed to be enhancers of viral replication. Analysis of viruses obtained from infected mosquitoes showed selection of mutations that mapped in DB2. Recombinant viruses carrying the identified variations confirmed that these mutations greatly increase viral replication in mosquito cells, with low or no impact in human cells. Use of viruses lacking each of the DB structures revealed opposite viral phenotypes. While deletion of DB1 reduced viral replication about 10-fold, viruses lacking DB2 displayed a great increase of fitness in mosquitoes, confirming a functional diversification of these similar RNA elements. Mechanistic analysis indicated that DB1 and DB2 differentially modulate viral genome cyclization and RNA replication. We found that a pseudoknot formed within DB2 competes with long-range RNA-RNA interactions that are necessary for minus-strand RNA synthesis. Our results support a model in which a functional diversification of duplicated RNA elements in the viral 3' UTR is driven by host-specific requirements. This study provides new ideas for understanding molecular aspects of the evolution of RNA viruses that naturally jump between different species.IMPORTANCE Flaviviruses constitute the most relevant group of arthropod-transmitted viruses, including important human pathogens such as the dengue, Zika, yellow fever, and West Nile viruses. The natural alternation of these viruses between vertebrate and invertebrate hosts shapes the viral genome population, which leads to selection of different viral variants with potential implications for epidemiological fitness and pathogenesis. However, the selective forces and mechanisms acting on the viral RNA during host adaptation are still largely unknown. Here, we found that two almost identical tandem RNA structures present at the viral 3' untranslated region are under different selective pressures in the two hosts. Mechanistic studies indicated that the two RNA elements, known as dumbbells, contain sequences that overlap essential RNA cyclization elements involved in viral RNA synthesis. The data support a model in which the duplicated RNA structures differentially evolved to accommodate distinct functions for viral replication in the two hosts.
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Klitting R, Fischer C, Drexler JF, Gould EA, Roiz D, Paupy C, de Lamballerie X. What Does the Future Hold for Yellow Fever Virus? (II). Genes (Basel) 2018; 9:E425. [PMID: 30134625 PMCID: PMC6162518 DOI: 10.3390/genes9090425] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/13/2018] [Accepted: 08/16/2018] [Indexed: 02/06/2023] Open
Abstract
As revealed by the recent resurgence of yellow fever virus (YFV) activity in the tropical regions of Africa and South America, YFV control measures need urgent rethinking. Over the last decade, most reported outbreaks occurred in, or eventually reached, areas with low vaccination coverage but that are suitable for virus transmission, with an unprecedented risk of expansion to densely populated territories in Africa, South America and Asia. As reflected in the World Health Organization's initiative launched in 2017, it is high time to strengthen epidemiological surveillance to monitor accurately viral dissemination, and redefine vaccination recommendation areas. Vector-control and immunisation measures need to be adapted and vaccine manufacturing must be reconciled with an increasing demand. We will have to face more yellow fever (YF) cases in the upcoming years. Hence, improving disease management through the development of efficient treatments will prove most beneficial. Undoubtedly, these developments will require in-depth descriptions of YFV biology at molecular, physiological and ecological levels. This second section of a two-part review describes the current state of knowledge and gaps regarding the molecular biology of YFV, along with an overview of the tools that can be used to manage the disease at the individual, local and global levels.
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Affiliation(s)
- Raphaëlle Klitting
- Unité des Virus Émergents (UVE: Aix-Marseille Univ⁻IRD 190⁻Inserm 1207⁻IHU Méditerranée Infection), 13385 Marseille CEDEX 05, France.
| | - Carlo Fischer
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, 10117 Berlin, Germany.
- German Center for Infection Research (DZIF), 38124 Braunschweig, Germany.
| | - Jan F Drexler
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, 10117 Berlin, Germany.
- German Center for Infection Research (DZIF), 38124 Braunschweig, Germany.
- Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov University, 119991 Moscow, Russia.
| | - Ernest A Gould
- Unité des Virus Émergents (UVE: Aix-Marseille Univ⁻IRD 190⁻Inserm 1207⁻IHU Méditerranée Infection), 13385 Marseille CEDEX 05, France.
| | - David Roiz
- UMR Maladies Infectieuses et Vecteurs: Écologie, Génétique Évolution et Contrôle (MIVEGEC: IRD, CNRS, Univ. Montpellier), 34394 Montpellier, France.
| | - Christophe Paupy
- UMR Maladies Infectieuses et Vecteurs: Écologie, Génétique Évolution et Contrôle (MIVEGEC: IRD, CNRS, Univ. Montpellier), 34394 Montpellier, France.
| | - Xavier de Lamballerie
- Unité des Virus Émergents (UVE: Aix-Marseille Univ⁻IRD 190⁻Inserm 1207⁻IHU Méditerranée Infection), 13385 Marseille CEDEX 05, France.
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9
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Klitting R, Riziki T, Moureau G, Piorkowski G, Gould EA, de Lamballerie X. Exploratory re-encoding of yellow fever virus genome: new insights for the design of live-attenuated viruses. Virus Evol 2018; 4:vey021. [PMID: 30057792 PMCID: PMC6057501 DOI: 10.1093/ve/vey021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Virus attenuation by genome re-encoding is a pioneering approach for generating effective live-attenuated vaccine candidates. Its core principle is to introduce a large number of synonymous substitutions into the viral genome to produce stable attenuation of the targeted virus. Introduction of large numbers of mutations has also been shown to maintain stability of the attenuated phenotype by lowering the risk of reversion and recombination of re-encoded genomes. Identifying mutations with low fitness cost is pivotal as this increases the number that can be introduced and generates more stable and attenuated viruses. Here, we sought to identify mutations with low deleterious impact on the in vivo replication and virulence of yellow fever virus (YFV). Following comparative bioinformatic analyses of flaviviral genomes, we categorised synonymous transition mutations according to their impact on CpG/UpA composition and secondary RNA structures. We then designed seventeen re-encoded viruses with 100–400 synonymous mutations in the NS2A-to-NS4B coding region of YFV Asibi and Ap7M (hamster-adapted) genomes. Each virus contained a panel of synonymous mutations designed according to the above categorisation criteria. The replication and fitness characteristics of parent and re-encoded viruses were compared in vitro using cell culture competition experiments. In vivo laboratory hamster models were also used to compare relative virulence and immunogenicity characteristics. Most of the re-encoded strains showed no decrease in replicative fitness in vitro. However, they showed reduced virulence and, in some instances, decreased replicative fitness in vivo. Importantly, the most attenuated of the re-encoded strains induced robust, protective immunity in hamsters following challenge with Ap7M, a virulent virus. Overall, the introduction of transitions with no or a marginal increase in the number of CpG/UpA dinucleotides had the mildest impact on YFV replication and virulence in vivo. Thus, this strategy can be incorporated in procedures for the finely tuned creation of substantially re-encoded viral genomes.
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Affiliation(s)
- R Klitting
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU Méditerranée Infection), Marseille, France
| | - T Riziki
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU Méditerranée Infection), Marseille, France
| | - G Moureau
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU Méditerranée Infection), Marseille, France
| | - G Piorkowski
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU Méditerranée Infection), Marseille, France
| | - E A Gould
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU Méditerranée Infection), Marseille, France
| | - X de Lamballerie
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU Méditerranée Infection), Marseille, France
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Morley VJ, Noval MG, Chen R, Weaver SC, Vignuzzi M, Stapleford KA, Turner PE. Chikungunya virus evolution following a large 3'UTR deletion results in host-specific molecular changes in protein-coding regions. Virus Evol 2018; 4:vey012. [PMID: 29942653 PMCID: PMC6007266 DOI: 10.1093/ve/vey012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The 3′untranslated region (UTR) in alphavirus genomes functions in virus replication and plays a role in determining virus host range. However, the molecular evolution of virus UTRs is understudied compared to the evolution of protein-coding regions. Chikungunya virus (CHIKV) has the longest 3′UTR among the alphaviruses (500–700 nt), and 3′UTR length and sequence structure vary substantially among different CHIKV lineages. Previous studies showed that genomic deletions and insertions are key drivers of CHIKV 3′UTR evolution. Inspired by hypothesized deletion events in the evolutionary history of CHIKV, we used experimental evolution to examine CHIKV adaptation in response to a large 3′UTR deletion. We engineered a CHIKV mutant with a 258 nt deletion in the 3′UTR (ΔDR1/2). This deletion reduced viral replication on mosquito cells, but did not reduce replication on mammalian cells. To examine how selective pressures from vertebrate and invertebrate hosts shape CHIKV evolution after a deletion in the 3′UTR, we passaged ΔDR1/2 virus populations strictly on primate cells, strictly on mosquito cells, or with alternating primate/mosquito cell passages. We found that virus populations passaged on a single host cell line increased in fitness relative to the ancestral deletion mutant on their selected host, and viruses that were alternately passaged improved on both hosts. Surprisingly, whole genome sequencing revealed few changes in the 3′UTR of passaged populations. Rather, virus populations evolved improved fitness through mutations in protein coding regions that were associated with specific hosts.
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Affiliation(s)
- Valerie J Morley
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06511-8934, USA
| | | | - Rubing Chen
- Institute for Human Infections and Immunity and Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Scott C Weaver
- Institute for Human Infections and Immunity and Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Marco Vignuzzi
- Viral Populations and Pathogenesis Unit, Institut Pasteur, Paris, France
| | | | - Paul E Turner
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06511-8934, USA.,Program in Microbiology, Yale School of Medicine, New Haven, CT, USA
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Dwivedi VD, Tripathi IP, Tripathi RC, Bharadwaj S, Mishra SK. Genomics, proteomics and evolution of dengue virus. Brief Funct Genomics 2018; 16:217-227. [PMID: 28073742 DOI: 10.1093/bfgp/elw040] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The genome of a pathogenic organism possesses a specific order of nucleotides that contains not only information about the synthesis and expression of proteomes, which are required for its growth and survival, but also about its evolution. Inhibition of any particular protein, which is required for the survival of that pathogenic organism, can be used as a potential therapeutic target for the development of effective drugs to treat its infections. In this review, the genomics, proteomics and evolution of dengue virus have been discussed, which will be helpful in better understanding of its origin, growth, survival and evolution, and may contribute toward development of new efficient anti-dengue drugs.
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The Regulation of Translation in Alphavirus-Infected Cells. Viruses 2018; 10:v10020070. [PMID: 29419763 PMCID: PMC5850377 DOI: 10.3390/v10020070] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/02/2018] [Accepted: 02/06/2018] [Indexed: 12/12/2022] Open
Abstract
Sindbis virus (SINV) contains an RNA genome of positive polarity with two open reading frames (ORFs). The first ORF is translated from the genomic RNA (gRNA), rendering the viral non-structural proteins, whereas the second ORF is translated from a subgenomic mRNA (sgRNA), which directs the synthesis of viral structural proteins. SINV infection strongly inhibits host cell translation through a variety of different mechanisms, including the phosphorylation of the eukaryotic initiation factor eIF2α and the redistribution of cellular proteins from the nucleus to the cytoplasm. A number of motifs have been identified in SINV sgRNA, including a hairpin downstream of the AUG initiation codon, which is involved in the translatability of the viral sgRNA when eIF2 is inactivated. Moreover, a 3′-UTR motif containing three stem-loop structures is involved in the enhancement of translation in insect cells, but not in mammalian cells. Accordingly, SINV sgRNA has evolved several structures to efficiently compete for the cellular translational machinery. Mechanistically, sgRNA translation involves scanning of the 5′-UTR following a non-canonical mode and without the requirement for several initiation factors. Indeed, sgRNA-directed polypeptide synthesis occurs even after eIF4G cleavage or inactivation of eIF4A by selective inhibitors. Remarkably, eIF2α phosphorylation does not hamper sgRNA translation during the late phase of SINV infection. SINV sgRNA thus constitutes a unique model of a capped viral mRNA that is efficiently translated in the absence of several canonical initiation factors. The present review will mainly focus in the non-canonical mechanism of translation of SINV sgRNA.
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13
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The 5' and 3' Untranslated Regions of the Flaviviral Genome. Viruses 2017; 9:v9060137. [PMID: 28587300 PMCID: PMC5490814 DOI: 10.3390/v9060137] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/16/2017] [Accepted: 05/29/2017] [Indexed: 01/30/2023] Open
Abstract
Flaviviruses are enveloped arthropod-borne viruses with a single-stranded, positive-sense RNA genome that can cause serious illness in humans and animals. The 11 kb 5′ capped RNA genome consists of a single open reading frame (ORF), and is flanked by 5′ and 3′ untranslated regions (UTR). The ORF is a polyprotein that is processed into three structural and seven non-structural proteins. The UTRs have been shown to be important for viral replication and immune modulation. Both of these regions consist of elements that are essential for genome cyclization, resulting in initiation of RNA synthesis. Genome mutation studies have been employed to investigate each component of the essential elements to show the necessity of each component and its role in viral RNA replication and growth. Furthermore, the highly structured 3′UTR is responsible for the generation of subgenomic flavivirus RNA (sfRNA) that helps the virus evade host immune response, thereby affecting viral pathogenesis. In addition, changes within the 3′UTR have been shown to affect transmissibility between vector and host, which can influence the development of vaccines.
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14
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Le Guillou-Guillemette H, Pivert A, Bouthry E, Henquell C, Petsaris O, Ducancelle A, Veillon P, Vallet S, Alain S, Thibault V, Abravanel F, Rosenberg AA, André-Garnier E, Bour JB, Baazia Y, Trimoulet P, André P, Gaudy-Graffin C, Bettinger D, Larrat S, Signori-Schmuck A, Saoudin H, Pozzetto B, Lagathu G, Minjolle-Cha S, Stoll-Keller F, Pawlotsky JM, Izopet J, Payan C, Lunel-Fabiani F, Lemaire C. Natural non-homologous recombination led to the emergence of a duplicated V3-NS5A region in HCV-1b strains associated with hepatocellular carcinoma. PLoS One 2017; 12:e0174651. [PMID: 28394908 PMCID: PMC5386276 DOI: 10.1371/journal.pone.0174651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 03/13/2017] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND The emergence of new strains in RNA viruses is mainly due to mutations or intra and inter-genotype homologous recombination. Non-homologous recombinations may be deleterious and are rarely detected. In previous studies, we identified HCV-1b strains bearing two tandemly repeated V3 regions in the NS5A gene without ORF disruption. This polymorphism may be associated with an unfavorable course of liver disease and possibly involved in liver carcinogenesis. Here we aimed at characterizing the origin of these mutant strains and identifying the evolutionary mechanism on which the V3 duplication relies. METHODS Direct sequencing of the entire NS5A and E1 genes was performed on 27 mutant strains. Quasispecies analyses in consecutive samples were also performed by cloning and sequencing the NS5A gene for all mutant and wild strains. We analyzed the mutant and wild-type sequence polymorphisms using Bayesian methods to infer the evolutionary history of and the molecular mechanism leading to the duplication-like event. RESULTS Quasispecies were entirely composed of exclusively mutant or wild-type strains respectively. Mutant quasispecies were found to have been present since contamination and had persisted for at least 10 years. This V3 duplication-like event appears to have resulted from non-homologous recombination between HCV-1b wild-type strains around 100 years ago. The association between increased liver disease severity and these HCV-1b mutants may explain their persistence in chronically infected patients. CONCLUSIONS These results emphasize the possible consequences of non-homologous recombination in the emergence and severity of new viral diseases.
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Affiliation(s)
- Hélène Le Guillou-Guillemette
- Laboratoire de Virologie, CHU Angers, France
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
| | - Adeline Pivert
- Laboratoire de Virologie, CHU Angers, France
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
| | - Elise Bouthry
- Laboratoire de Virologie, CHU Angers, France
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
| | | | - Odile Petsaris
- Département de Bactériologie-Virologie-Hygiène Hospitalière et Parasitologie-Mycologie, CHRU, LUBEM, Brest, France
| | - Alexandra Ducancelle
- Laboratoire de Virologie, CHU Angers, France
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
| | - Pascal Veillon
- Laboratoire de Virologie, CHU Angers, France
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
| | - Sophie Vallet
- Département de Bactériologie-Virologie-Hygiène Hospitalière et Parasitologie-Mycologie, CHRU, LUBEM, Brest, France
| | | | | | - Florence Abravanel
- Laboratoire de Virologie, CNR VHE, Inserm U1043, CHU Purpan, Toulouse, France
| | - Arielle A. Rosenberg
- AP-HP, GHU Cochin, Laboratoire de Virologie, Université Paris Descartes, Paris, France
| | | | | | - Yazid Baazia
- Laboratoire de Virologie, CHU Avicenne, Bobigny, France
| | - Pascale Trimoulet
- Laboratoire de Virologie, Hôpital Pellegrin Tripode, CHU Bordeaux, France
| | - Patrice André
- Laboratoire de Virologie, Centre de Biologie Nord, Hôpital de la Croix Rousse, Lyon, France
| | | | | | - Sylvie Larrat
- Laboratoire de Virologie, UMI 3265 UJF-EMBL-CNRS, CHU, Unit of Virus Host Cell Interactions, Grenoble, France
| | - Anne Signori-Schmuck
- Laboratoire de Virologie, UMI 3265 UJF-EMBL-CNRS, CHU, Unit of Virus Host Cell Interactions, Grenoble, France
| | - Hénia Saoudin
- Laboratoire de Bactériologie-Virologie, CHU Saint-Etienne, France
| | - Bruno Pozzetto
- Laboratoire de Bactériologie-Virologie, CHU Saint-Etienne, France
| | | | | | | | | | - Jacques Izopet
- Laboratoire de Virologie, CNR VHE, Inserm U1043, CHU Purpan, Toulouse, France
| | - Christopher Payan
- Département de Bactériologie-Virologie-Hygiène Hospitalière et Parasitologie-Mycologie, CHRU, LUBEM, Brest, France
| | - Françoise Lunel-Fabiani
- Laboratoire de Virologie, CHU Angers, France
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
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Bavia L, Mosimann ALP, Aoki MN, Duarte Dos Santos CN. A glance at subgenomic flavivirus RNAs and microRNAs in flavivirus infections. Virol J 2016; 13:84. [PMID: 27233361 PMCID: PMC4884392 DOI: 10.1186/s12985-016-0541-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/17/2016] [Indexed: 11/10/2022] Open
Abstract
The family Flaviviridae comprises a wide variety of viruses that are distributed worldwide, some of which are associated with high rates of morbidity and mortality. There are neither vaccines nor antivirals for most flavivirus infections, reinforcing the importance of research on different aspects of the viral life cycle. During infection, cytoplasmic accumulation of RNA fragments mainly originating from the 3' UTRs, which have been designated subgenomic flavivirus RNAs (sfRNAs), has been detected. It has been shown that eukaryotic exoribonucleases are involved in viral sfRNA production. Additionally, viral and human small RNAs (sRNAs) have also been found in flavivirus-infected cells, especially microRNAs (miRNAs). miRNAs were first described in eukaryotic cells and in a mature and functional state present as single-stranded 18-24 nt RNA fragments. Their main function is the repression of translation through base pairing with cellular mRNAs, besides other functions, such as mRNA degradation. Canonical miRNA biogenesis involves Drosha and Dicer, however miRNA can also be generated by alternative pathways. In the case of flaviviruses, alternative pathways have been suggested. Both sfRNAs and miRNAs are involved in viral infection and host cell response modulation, representing interesting targets of antiviral strategies. In this review, we focus on the generation and function of viral sfRNAs, sRNAs and miRNAs in West Nile, dengue, Japanese encephalitis, Murray Valley encephalitis and yellow fever infections, as well as their roles in viral replication, translation and cell immune response evasion. We also give an overview regarding other flaviviruses and the generation of cellular miRNAs during infection.
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Affiliation(s)
- Lorena Bavia
- Laboratório de Virologia Molecular, Instituto Carlos Chagas (ICC/FIOCRUZ-PR), Rua Prof. Algacyr Munhoz Mader 3775, CIC, CEP: 81350-010, Curitiba, Paraná, Brazil
| | - Ana Luiza Pamplona Mosimann
- Laboratório de Virologia Molecular, Instituto Carlos Chagas (ICC/FIOCRUZ-PR), Rua Prof. Algacyr Munhoz Mader 3775, CIC, CEP: 81350-010, Curitiba, Paraná, Brazil
| | - Mateus Nóbrega Aoki
- Laboratório de Virologia Molecular, Instituto Carlos Chagas (ICC/FIOCRUZ-PR), Rua Prof. Algacyr Munhoz Mader 3775, CIC, CEP: 81350-010, Curitiba, Paraná, Brazil
| | - Claudia Nunes Duarte Dos Santos
- Laboratório de Virologia Molecular, Instituto Carlos Chagas (ICC/FIOCRUZ-PR), Rua Prof. Algacyr Munhoz Mader 3775, CIC, CEP: 81350-010, Curitiba, Paraná, Brazil.
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Garcia-Moreno M, Sanz MA, Carrasco L. A Viral mRNA Motif at the 3'-Untranslated Region that Confers Translatability in a Cell-Specific Manner. Implications for Virus Evolution. Sci Rep 2016; 6:19217. [PMID: 26755446 PMCID: PMC4709744 DOI: 10.1038/srep19217] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 12/08/2015] [Indexed: 11/25/2022] Open
Abstract
Sindbis virus (SINV) mRNAs contain several motifs that participate in the regulation of their translation. We have discovered a motif at the 3′ untranslated region (UTR) of viral mRNAs, constituted by three repeated sequences, which is involved in the translation of both SINV genomic and subgenomic mRNAs in insect, but not in mammalian cells. These data illustrate for the first time that an element present at the 3′-UTR confers translatability to mRNAs from an animal virus in a cell-specific manner. Sequences located at the beginning of the 5′-UTR may also regulate SINV subgenomic mRNA translation in both cell lines in a context of infection. Moreover, a replicon derived from Sleeping disease virus, an alphavirus that have no known arthropod vector for transmission, is much more efficient in insect cells when the repeated sequences from SINV are inserted at its 3′-UTR, due to the enhanced translatability of its mRNAs. Thus, these findings provide a clue to understand, at the molecular level, the evolution of alphaviruses and their host range.
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Affiliation(s)
| | - Miguel Angel Sanz
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Madrid, Spain
| | - Luis Carrasco
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Madrid, Spain
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Ecuador Paraiso Escondido Virus, a New Flavivirus Isolated from New World Sand Flies in Ecuador, Is the First Representative of a Novel Clade in the Genus Flavivirus. J Virol 2015; 89:11773-85. [PMID: 26355096 PMCID: PMC4645344 DOI: 10.1128/jvi.01543-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 09/04/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies (Psathyromyia abonnenci, formerly Lutzomyia abonnenci) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogenetic analysis of the complete coding sequence showed that EPEV represents a distinct clade which diverged from a lineage that was ancestral to the nonvectored flaviviruses Entebbe bat virus, Yokose virus, and Sokoluk virus and also the Aedes-associated mosquito-borne flaviviruses, which include yellow fever virus, Sepik virus, Saboya virus, and others. EPEV replicated in C6/36 mosquito cells, yielding high infectious titers, but failed to reproduce either in vertebrate cell lines (Vero, BHK, SW13, and XTC cells) or in suckling mouse brains. This surprising result, which appears to eliminate an association with vertebrate hosts in the life cycle of EPEV, is discussed in the context of the evolutionary origins of EPEV in the New World. IMPORTANCE The flaviviruses are rarely (if ever) vectored by sand fly species, at least in the Old World. We have identified the first representative of a sand fly-associated flavivirus, Ecuador Paraiso Escondido virus (EPEV), in the New World. EPEV constitutes a novel clade according to current knowledge of the flaviviruses. Phylogenetic analysis of the virus genome showed that EPEV roots the Aedes-associated mosquito-borne flaviviruses, including yellow fever virus. In light of this new discovery, the New World origin of EPEV is discussed together with that of the other flaviviruses.
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Le Guillou-Guillemette H, Ducancelle A, Bertrais S, Lemaire C, Pivert A, Veillon P, Bouthry E, Alain S, Thibault V, Abravanel F, Rosenberg AR, Henquell C, André-Garnier E, Petsaris O, Vallet S, Bour JB, Baazia Y, Trimoulet P, André P, Gaudy-Graffin C, Bettinger D, Larrat S, Signori-Schmuck A, Saoudin H, Pozzetto B, Lagathu G, Minjolle-Cha S, Stoll-Keller F, Pawlotsky JM, Izopet J, Payan C, Lunel-Fabiani F. Identification of a duplicated V3 domain in NS5A associated with cirrhosis and hepatocellular carcinoma in HCV-1b patients. J Clin Virol 2015. [PMID: 26209408 DOI: 10.1016/j.jcv.2015.06.096] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND The NS5A protein of the hepatitis C virus has been shown to be involved in the development of hepatocellular carcinoma. OBJECTIVES In a French multicenter study, we investigated the clinical and epidemiological features of a new HCV genotype 1b strain bearing a wide insertion into the V3 domain. STUDY DESIGN We studied NS5A gene sequences in 821 French patients infected with genotype 1b HCV. RESULTS We identified an uncharacterized V3 insertion without ORF disruption in 3.05% of the HCV sequences. The insertion comprised 31 amino-acids for the majority of patients; 3 patients had 27 amino-acids insertions and 1 had a 12 amino-acids insertion. Sequence identity between the 31 amino-acids insertions and the V3 domain ranged from 48 to 96% with E-values above 4e(-5), thus illustrating sequence homology and a partial gene duplication event that to our knowledge has never been reported in HCV. Moreover we showed the presence of the duplication at the time of infection and its persistence at least during 12 years in the entire quasispecies. No association was found with extrahepatic diseases. Conversely, patients with cirrhosis were two times more likely to have HCV with this genetic characteristic (p=0.04). Moreover, its prevalence increased with liver disease severity (from 3.0% in patients without cirrhosis to 9.4% in patients with both cirrhosis and HCC, p for trend=0.045). CONCLUSIONS We identified a duplicated V3 domain in the HCV-1b NS5A protein for the first time. The duplication may be associated with unfavorable evolution of liver disease including a possible involvement in liver carcinogenesis.
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Affiliation(s)
- H Le Guillou-Guillemette
- Laboratoire de Virologie, CHU Angers, France; HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France.
| | - A Ducancelle
- Laboratoire de Virologie, CHU Angers, France; HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France.
| | - S Bertrais
- HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France.
| | - C Lemaire
- IRHS, PRES LUNAM, SFR QUASAV, Angers, France.
| | - A Pivert
- Laboratoire de Virologie, CHU Angers, France; HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France.
| | - P Veillon
- Laboratoire de Virologie, CHU Angers, France; HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France.
| | - E Bouthry
- Laboratoire de Virologie, CHU Angers, France; HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France
| | - S Alain
- Laboratoire de Virologie, CHU Limoges, France.
| | - V Thibault
- Laboratoire de Virologie, CHU Pitié-Salpêtrière, Paris, France.
| | - F Abravanel
- Laboratoire de Virologie, CNR VHE, Inserm U1043, CHU Purpan, Toulouse, France.
| | - A R Rosenberg
- AP-HP, GHU Cochin, Laboratoire de Virologie, Université Paris Descartes, EA 4474 "Hepatitis C Virology", Paris, France.
| | - C Henquell
- Laboratoire de Virologie, CHU Clermont-Ferrand, France.
| | | | - O Petsaris
- Département de Bactériologie-Virologie-Hygiène Hospitalière et Parasitologie-Mycologie, CHRU, LUBEM, EA3882, Brest, France.
| | - S Vallet
- Département de Bactériologie-Virologie-Hygiène Hospitalière et Parasitologie-Mycologie, CHRU, LUBEM, EA3882, Brest, France.
| | - J B Bour
- Laboratoire de Virologie, CHU, Dijon, France.
| | - Y Baazia
- Laboratoire de Virologie, CHU Avicenne, Bobigny, France.
| | - P Trimoulet
- Laboratoire de Virologie, Hôpital Pellegrin Tripode, CHU Bordeaux, France.
| | - P André
- Laboratoire de Virologie, Centre de Biologie Nord, Hôpital de la Croix Rousse, Lyon, France.
| | - C Gaudy-Graffin
- Université François Rabelais, Inserm U966, CHU Tours, France.
| | - D Bettinger
- Laboratoire de Virologie, CHU Besançon, France.
| | - S Larrat
- Laboratoire de Virologie, UMI 3265 UJF-EMBL-CNRS, CHU, Unit of Virus Host Cell Interactions, Grenoble, France.
| | - A Signori-Schmuck
- Laboratoire de Virologie, UMI 3265 UJF-EMBL-CNRS, CHU, Unit of Virus Host Cell Interactions, Grenoble, France.
| | - H Saoudin
- Laboratoire de Bactériologie-Virologie, CHU Saint-Etienne, France.
| | - B Pozzetto
- Laboratoire de Bactériologie-Virologie, CHU Saint-Etienne, France.
| | - G Lagathu
- Laboratoire de Virologie, CHU Rennes, France.
| | | | - F Stoll-Keller
- Institut de Virologie, CHU Strasbourg, Inserm U748, Strasbourg, France.
| | - J M Pawlotsky
- Laboratoire de Virologie-Bactériologie, CHU Henri-Mondor, Créteil, France.
| | - J Izopet
- Laboratoire de Virologie, CNR VHE, Inserm U1043, CHU Purpan, Toulouse, France.
| | - C Payan
- Département de Bactériologie-Virologie-Hygiène Hospitalière et Parasitologie-Mycologie, CHRU, LUBEM, EA3882, Brest, France.
| | - F Lunel-Fabiani
- Laboratoire de Virologie, CHU Angers, France; HIFIH Laboratory, UPRES 3859, SFR 4208, LUNAM University, Angers, France.
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19
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Brinton MA, Basu M. Functions of the 3' and 5' genome RNA regions of members of the genus Flavivirus. Virus Res 2015; 206:108-19. [PMID: 25683510 DOI: 10.1016/j.virusres.2015.02.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/04/2015] [Indexed: 11/26/2022]
Abstract
The positive sense genomes of members of the genus Flavivirus in the family Flaviviridae are ∼ 11 kb in length and have a 5' type I cap but no 3' poly-A. The 3' and 5' terminal regions contain short conserved sequences that are proposed to be repeated remnants of an ancient sequence. However, the functions of most of these conserved sequences have not yet been determined. The terminal regions of the genome also contain multiple conserved RNA structures. Functional data for many of these structures have been obtained. Three sets of complementary 3' and 5' terminal region sequences, some of which are located in conserved RNA structures, interact to form a panhandle structure that is required for initiation of minus strand RNA synthesis with the 5' terminal structure functioning as the promoter. How the switch from the terminal RNA structure base pairing to the long distance RNA-RNA interaction is triggered and regulated is not well understood but evidence suggests involvement of a cell protein binding to three sites on the 3' terminal RNA structures and a cis-acting metastable 3' RNA element in the 3' terminal RNA structure. Cell proteins may also be involved in facilitating exponential replication of nascent genomic RNA within replication vesicles at later times of the infection cycle. Other conserved RNA structures and/or sequences in the 3' and 5' terminal regions have been proposed to regulate genome translation. Additional functions of the 3' and 5' terminal sequences have also been reported.
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Affiliation(s)
- Margo A Brinton
- Department of Biology, Georgia State University, Atlanta, GA, USA.
| | - Mausumi Basu
- Department of Biology, Georgia State University, Atlanta, GA, USA
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20
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Villordo SM, Filomatori CV, Sánchez-Vargas I, Blair CD, Gamarnik AV. Dengue virus RNA structure specialization facilitates host adaptation. PLoS Pathog 2015; 11:e1004604. [PMID: 25635835 PMCID: PMC4311971 DOI: 10.1371/journal.ppat.1004604] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 12/04/2014] [Indexed: 12/29/2022] Open
Abstract
Many viral pathogens cycle between humans and insects. These viruses must have evolved strategies for rapid adaptation to different host environments. However, the mechanistic basis for the adaptation process remains poorly understood. To study the mosquito-human adaptation cycle, we examined changes in RNA structures of the dengue virus genome during host adaptation. Deep sequencing and RNA structure analysis, together with fitness evaluation, revealed a process of host specialization of RNA elements of the viral 3’UTR. Adaptation to mosquito or mammalian cells involved selection of different viral populations harvesting mutations in a single stem-loop structure. The host specialization of the identified RNA structure resulted in a significant viral fitness cost in the non-specialized host, posing a constraint during host switching. Sequence conservation analysis indicated that the identified host adaptable stem loop structure is duplicated in dengue and other mosquito-borne viruses. Interestingly, functional studies using recombinant viruses with single or double stem loops revealed that duplication of the RNA structure allows the virus to accommodate mutations beneficial in one host and deleterious in the other. Our findings reveal new concepts in adaptation of RNA viruses, in which host specialization of RNA structures results in high fitness in the adapted host, while RNA duplication confers robustness during host switching. Important viral pathogens, such as influenza and dengue, jump between species; however, it is still unclear how these viruses evolved for efficient replication in significantly different environments. Using dengue virus as a model, which naturally alternates between humans and mosquitoes, changes in the viral RNA were investigated in each host. Deep sequencing analysis revealed the selection of strikingly different viral populations during host adaptation. Fitness measurements indicated that mutations in a single RNA structure of the viral 3’ untranslated region were responsible for positive and negative selection of specific viral variants in the two hosts. Cycles of disruption and reconstitution of this RNA structure were observed during host switching, identifying a host adaptable RNA element. Importantly, natural duplication of this RNA was found to be required to tolerate mosquito-associated mutations for efficient replication in mammalian cells. Our studies revealed a novel strategy of viral adaptation, where RNA structure specialization and duplication provide a mechanism for maintaining high viral fitness in each host and efficiency during host cycling. Because the identified RNA structure and its duplication are conserved in many mosquito-borne flaviviruses, our findings using dengue virus could help to understand RNA evolution of an extensive group of human pathogens.
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Affiliation(s)
| | | | - Irma Sánchez-Vargas
- Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Carol D. Blair
- Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
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21
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Kenney JL, Solberg OD, Langevin SA, Brault AC. Characterization of a novel insect-specific flavivirus from Brazil: potential for inhibition of infection of arthropod cells with medically important flaviviruses. J Gen Virol 2014; 95:2796-2808. [PMID: 25146007 DOI: 10.1099/vir.0.068031-0] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the past decade, there has been an upsurge in the number of newly described insect-specific flaviviruses isolated pan-globally. We recently described the isolation of a novel flavivirus (tentatively designated 'Nhumirim virus'; NHUV) that represents an example of a unique subset of apparently insect-specific viruses that phylogenetically affiliate with dual-host mosquito-borne flaviviruses despite appearing to be limited to replication in mosquito cells. We characterized the in vitro growth potential and 3' untranslated region (UTR) sequence homology with alternative flaviviruses, and evaluated the virus's capacity to suppress replication of representative Culex spp.-vectored pathogenic flaviviruses in mosquito cells. Only mosquito cell lines were found to support NHUV replication, further reinforcing the insect-specific phenotype of this virus. Analysis of the sequence and predicted RNA secondary structures of the 3' UTR indicated NHUV to be most similar to viruses within the yellow fever serogroup and Japanese encephalitis serogroup, and viruses in the tick-borne flavivirus clade. NHUV was found to share the fewest conserved sequence elements when compared with traditional insect-specific flaviviruses. This suggests that, despite apparently being insect specific, this virus probably diverged from an ancestral mosquito-borne flavivirus. Co-infection experiments indicated that prior or concurrent infection of mosquito cells with NHUV resulted in a significant reduction in virus production of West Nile virus (WNV), St Louis encephalitis virus (SLEV) and Japanese encephalitis virus. The inhibitory effect was most effective against WNV and SLEV with over a 10(6)-fold and 10(4)-fold reduction in peak titres, respectively.
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Affiliation(s)
- Joan L Kenney
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA
| | | | | | - Aaron C Brault
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA
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22
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Gritsun DJ, Jones IM, Gould EA, Gritsun TS. Molecular archaeology of Flaviviridae untranslated regions: duplicated RNA structures in the replication enhancer of flaviviruses and pestiviruses emerged via convergent evolution. PLoS One 2014; 9:e92056. [PMID: 24647143 PMCID: PMC3960163 DOI: 10.1371/journal.pone.0092056] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 02/17/2014] [Indexed: 12/29/2022] Open
Abstract
RNA secondary structures in the 3'untranslated regions (3'UTR) of the viruses of the family Flaviviridae, previously identified as essential (promoters) or beneficial (enhancers) for replication, have been analysed. Duplicated enhancer elements are revealed as a global feature in the evolution of the 3'UTR of distantly related viruses within the genera Flavivirus and Pestivirus. For the flaviviruses, duplicated structures occur in the 3'UTR of all four distantly related ecological virus subgroups (tick-borne, mosquito-borne, no known vector and insect-specific flaviviruses (ISFV). RNA structural differences distinguish tick-borne flaviviruses with discrete pathogenetic characteristics. For Aedes- and Culex-associated ISFV, secondary RNA structures with different conformations display numerous short ssRNA direct repeats, exposed as loops and bulges. Long quadruplicate regions comprise almost the entire 3'UTR of Culex-associated ISFV. Extended duplicated sequence and associated RNA structures were also discovered in the 3'UTR of pestiviruses. In both the Flavivirus and Pestivirus genera, duplicated RNA structures were localized to the enhancer regions of the 3'UTR suggesting an adaptive role predominantly in wild-type viruses. We propose sequence reiteration might act as a scaffold for dimerization of proteins involved in assembly of viral replicase complexes. Numerous nucleotide repeats exposed as loops/bulges might also interfere with host immune responses acting as a molecular sponge to sequester key host proteins or microRNAs.
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Affiliation(s)
- Dmitri J. Gritsun
- School of Biological Sciences, University of Reading, Whiteknights, Reading, United Kingdom
| | - Ian M. Jones
- School of Biological Sciences, University of Reading, Whiteknights, Reading, United Kingdom
| | - Ernest A. Gould
- Unité des Virus Emergents, Faculté de Médecine Timone, Marseille, France
| | - Tamara S. Gritsun
- School of Biological Sciences, University of Reading, Whiteknights, Reading, United Kingdom
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23
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Tromas N, Zwart MP, Forment J, Elena SF. Shrinkage of genome size in a plant RNA virus upon transfer of an essential viral gene into the host genome. Genome Biol Evol 2014; 6:538-50. [PMID: 24558257 PMCID: PMC3971587 DOI: 10.1093/gbe/evu036] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2014] [Indexed: 11/12/2022] Open
Abstract
Nonretroviral integrated RNA viruses (NIRVs) are genes of nonretroviral RNA viruses found in the genomes of many eukaryotic organisms. NIRVs are thought to sometimes confer virus resistance, meaning that they could impact spread of the virus in the host population. However, a NIRV that is expressed may also impact the evolution of virus populations within host organisms. Here, we experimentally addressed the evolution of a virus in a host expressing a NIRV using Tobacco etch virus (TEV), a plant RNA virus, and transgenic tobacco plants expressing its replicase, NIb. We found that a virus missing the NIb gene, TEV-ΔNIb, which is incapable of autonomous replication in wild-type plants, had a higher fitness than the full-length TEV in the transgenic plants. Moreover, when the full-length TEV was evolved by serial passages in transgenic plants, we observed genomic deletions within NIb--and in some cases the adjacent cistrons--starting from the first passage. When we passaged TEV and TEV-ΔNIb in transgenic plants, we found mutations in proteolytic sites, but these only occurred in TEV-ΔNIb lineages, suggesting the adaptation of polyprotein processing to altered NIb expression. These results raise the possibility that NIRV expression can indeed induce the deletion of the corresponding genes in the viral genome, resulting in the formation of viruses that are replication defective in hosts that do not express the same NIRV. Moreover, virus genome evolution was contingent upon the deletion of the viral replicase, suggesting NIRV expression could also alter patterns of virus evolution.
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Affiliation(s)
- Nicolas Tromas
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-UPV, València, Spain
| | - Mark P. Zwart
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-UPV, València, Spain
| | - Javier Forment
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-UPV, València, Spain
| | - Santiago F. Elena
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-UPV, València, Spain
- The Santa Fe Institute, Santa Fe, New Mexico
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24
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Chen R, Wang E, Tsetsarkin KA, Weaver SC. Chikungunya virus 3' untranslated region: adaptation to mosquitoes and a population bottleneck as major evolutionary forces. PLoS Pathog 2013; 9:e1003591. [PMID: 24009512 PMCID: PMC3757053 DOI: 10.1371/journal.ppat.1003591] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/19/2013] [Indexed: 12/11/2022] Open
Abstract
The 3' untranslated genome region (UTR) of arthropod-borne viruses is characterized by enriched direct repeats (DRs) and stem-loop structures. Despite many years of theoretical and experimental study, on-going positive selection on the 3'UTR had never been observed in 'real-time,' and the role of the arbovirus 3'UTR remains poorly understood. We observed a lineage-specific 3'UTR sequence pattern in all available Asian lineage of the mosquito-borne alphavirus, chikungunya virus (CHIKV) (1958-2009), including complicated mutation and duplication patterns of the long DRs. Given that a longer genome is usually associated with less efficient replication, we hypothesized that the fixation of these genetic changes in the Asian lineage 3'UTR was due to their beneficial effects on adaptation to vectors or hosts. Using reverse genetic methods, we examined the functional importance of each direct repeat. Our results suggest that adaptation to mosquitoes, rather than to mammalian hosts, is a major evolutionary force on the CHIKV 3'UTR. Surprisingly, the Asian 3'UTR appeared to be inferior to its predicted ancestral sequence for replication in both mammals and mosquitoes, suggesting that its fixation in Asia was not a result of directional selection. Rather, it may have resulted from a population bottleneck during its introduction from Africa to Asia. We propose that this introduction of a 3'UTR with deletions led to genetic drift and compensatory mutations associated with the loss of structural/functional constraints, followed by two independent beneficial duplications and fixation due to positive selection. Our results provide further evidence that the limited epidemic potential of the Asian CHIKV strains resulted from founder effects that reduced its fitness for efficient transmission by mosquitoes there.
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Affiliation(s)
- Rubing Chen
- Center for Tropical Diseases and Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Eryu Wang
- Center for Tropical Diseases and Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Konstantin A. Tsetsarkin
- Center for Tropical Diseases and Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Scott C. Weaver
- Center for Tropical Diseases and Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America,
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25
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Mini-genome rescue of Crimean-Congo hemorrhagic fever virus and research into the evolutionary patterns of its untranslated regions. Virus Res 2013; 177:22-34. [PMID: 23891575 DOI: 10.1016/j.virusres.2013.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Revised: 07/04/2013] [Accepted: 07/05/2013] [Indexed: 11/23/2022]
Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV) is a member of genus Nairovirus, family Bunyaviridae, which are distributed widely in Africa, Europe and Asia with several genotypes. As a BSL-4 level pathogen, the requirement of high-level biosafety facilities severely constrains researches on live virus manipulation. In this study, we developed a helper-virus-independent mini-genome rescue system for the Chinese YL04057 strain. Based on the enhanced green fluorescent protein (EGFP)-derived mini-genome plasmids, this polymerase I driven system permits easy observation and quantification. Unlike previous report, gradually reduced levels of activity of the CCHFV L, M and S untranslated regions (UTRs) were observed in our system. We also demonstrated that the UTRs at both ends were indispensable for mini-genome background expression. In addition, we phylogentically analyzed all six UTRs of CCHFV and showed that L-UTRs were clustered together approximately corresponding to their original geographical continents. The UTRs of M segment showed a similar branch structure to its open reading frames (ORFs), and nearly an identical tree was generated with 5' UTRs of S segment compared with its ORFs. However, the 3' UTRs of S segment formed new divergent groups. Compatibility tests of YL04057 strain nucleocapsid protein and L protein expression plasmids with Nigerian strain IbAr10200 mini-genomes revealed lower compatibility of L-UTRs without an obvious effect on M-UTRs. Moreover, we demonstrated that the L-UTRs could tolerate certain nucleotide mutations. This system may provide a foundation for future studies of the viral replication cycle, pathogenic mechanisms and evolutionary patterns of CCHFV.
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26
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May FJ, Clark DC, Pham K, Diviney SM, Williams DT, Field EJ, Kuno G, Chang GJ, Cheah WY, Setoh YX, Prow NA, Hobson-Peters J, Hall RA. Genetic divergence among members of the Kokobera group of flaviviruses supports their separation into distinct species. J Gen Virol 2013; 94:1462-1467. [PMID: 23426358 DOI: 10.1099/vir.0.049940-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The Kokobera virus group comprises mosquito-borne flaviviruses that cluster together phylogenetically. These viruses are unique to Australia and Papua New Guinea, and have been associated with a mild polyarticular disease in humans. Recent isolation of genetically diverse viruses within this group has prompted analysis of their genetic and phenotypic relationships. Phylogenetic analysis based on complete ORF, the envelope gene or the NS5/3' untranslated region supported the separation of the group into distinct species: Kokobera virus (KOKV), Stratford virus, New Mapoon virus, MK7979 and TS5273. Virulence studies in 3-week-old mice also provided the first evidence that a member of the KOKV group (MK7979) was neuroinvasive after intraperitoneal inoculation. In this context, our recent detection of KOKV group-specific antibodies in horses in the field suggests that these viruses should be considered in the epidemiology of flavivirus encephalitis in Australia.
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Affiliation(s)
- Fiona J May
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - David C Clark
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Kim Pham
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Sinéad M Diviney
- School of Biomedical Sciences, Curtin University, Bentley 6102, Western Australia, Australia
| | - David T Williams
- School of Biomedical Sciences, Curtin University, Bentley 6102, Western Australia, Australia
| | - Emma J Field
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Goro Kuno
- Arboviral Diseases Branch, Division of Vector-Borne Infectious Diseases, National Center for Zoonotic, Vector-borne and Enteric Diseases, Centers for Disease Control and Prevention (CDC), Fort Collins 80521, CO, USA
| | - Gwong-Jen Chang
- Arboviral Diseases Branch, Division of Vector-Borne Infectious Diseases, National Center for Zoonotic, Vector-borne and Enteric Diseases, Centers for Disease Control and Prevention (CDC), Fort Collins 80521, CO, USA
| | - Wai Yuen Cheah
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Yin X Setoh
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Natalie A Prow
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Jody Hobson-Peters
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Roy A Hall
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia 4072, Queensland, Australia
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27
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Biological and phylogenetic characteristics of yellow fever virus lineages from West Africa. J Virol 2012; 87:2895-907. [PMID: 23269797 DOI: 10.1128/jvi.01116-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The yellow fever virus (YFV), the first proven human-pathogenic virus, although isolated in 1927, is still a major public health problem, especially in West Africa where it causes outbreaks every year. Nevertheless, little is known about its genetic diversity and evolutionary dynamics, mainly due to a limited number of genomic sequences from wild virus isolates. In this study, we analyzed the phylogenetic relationships of 24 full-length genomes from YFV strains isolated between 1973 and 2005 in a sylvatic context of West Africa, including 14 isolates that had previously not been sequenced. By this, we confirmed genetic variability within one genotype by the identification of various YF lineages circulating in West Africa. Further analyses of the biological properties of these lineages revealed differential growth behavior in human liver and insect cells, correlating with the source of isolation and suggesting host adaptation. For one lineage, repeatedly isolated in a context of vertical transmission, specific characteristics in the growth behavior and unique mutations of the viral genome were observed and deserve further investigation to gain insight into mechanisms involved in YFV emergence and maintenance in nature.
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28
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Rossi SL, Nasar F, Cardosa J, Mayer SV, Tesh RB, Hanley KA, Weaver SC, Vasilakis N. Genetic and phenotypic characterization of sylvatic dengue virus type 4 strains. Virology 2011; 423:58-67. [PMID: 22178263 DOI: 10.1016/j.virol.2011.11.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 11/09/2011] [Accepted: 11/11/2011] [Indexed: 11/27/2022]
Abstract
Four serotypes of dengue virus (DENV 1-4) currently circulate between humans and domestic/peridomestic Aedes mosquitoes, resulting in 100 million infections per year. All four serotypes emerged, independently, from sylvatic progenitors transmitted among non-human primates by arboreal Aedes mosquitoes. This study investigated the genetic and phenotypic changes associated with emergence of human DENV-4 from its sylvatic ancestors. Analysis of complete genomes of 3 sylvatic and 4 human strains revealed high conservation of both the 5'- and 3'-untranslated regions but considerable divergence within the open reading frame. Additionally, the two ecotypes did not differ significantly in replication dynamics in cultured human liver (Huh-7), monkey kidney (Vero) or mosquito (C6/36) cells, although significant inter-strain variation within ecotypes was detected. These findings are in partial agreement with previous studies of DENV-2, where human strains produced a larger number of progeny than sylvatic strains in human liver cells but not in monkey or mosquito cells.
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Affiliation(s)
- S L Rossi
- Center for Biodefense and Emerging Infectious Diseases and Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0610, USA
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Gebhard LG, Filomatori CV, Gamarnik AV. Functional RNA elements in the dengue virus genome. Viruses 2011; 3:1739-56. [PMID: 21994804 PMCID: PMC3187688 DOI: 10.3390/v3091739] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 08/27/2011] [Accepted: 08/30/2011] [Indexed: 12/17/2022] Open
Abstract
Dengue virus (DENV) genome amplification is a process that involves the viral RNA, cellular and viral proteins, and a complex architecture of cellular membranes. The viral RNA is not a passive template during this process; it plays an active role providing RNA signals that act as promoters, enhancers and/or silencers of the replication process. RNA elements that modulate RNA replication were found at the 5′ and 3′ UTRs and within the viral coding sequence. The promoter for DENV RNA synthesis is a large stem loop structure located at the 5′ end of the genome. This structure specifically interacts with the viral polymerase NS5 and promotes RNA synthesis at the 3′ end of a circularized genome. The circular conformation of the viral genome is mediated by long range RNA-RNA interactions that span thousands of nucleotides. Recent studies have provided new information about the requirement of alternative, mutually exclusive, structures in the viral RNA, highlighting the idea that the viral genome is flexible and exists in different conformations. In this article, we describe elements in the promoter SLA and other RNA signals involved in NS5 polymerase binding and activity, and provide new ideas of how dynamic secondary and tertiary structures of the viral RNA participate in the viral life cycle.
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Affiliation(s)
- Leopoldo G Gebhard
- Fundación Instituto Leloir-CONICET, Avenida Patricias Argentinas 435, C1405BWE, Buenos Aires, Argentina.
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30
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Manzano M, Reichert ED, Polo S, Falgout B, Kasprzak W, Shapiro BA, Padmanabhan R. Identification of cis-acting elements in the 3'-untranslated region of the dengue virus type 2 RNA that modulate translation and replication. J Biol Chem 2011; 286:22521-34. [PMID: 21515677 PMCID: PMC3121397 DOI: 10.1074/jbc.m111.234302] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 04/21/2011] [Indexed: 12/30/2022] Open
Abstract
Using the massively parallel genetic algorithm for RNA folding, we show that the core region of the 3'-untranslated region of the dengue virus (DENV) RNA can form two dumbbell structures (5'- and 3'-DBs) of unequal frequencies of occurrence. These structures have the propensity to form two potential pseudoknots between identical five-nucleotide terminal loops 1 and 2 (TL1 and TL2) and their complementary pseudoknot motifs, PK2 and PK1. Mutagenesis using a DENV2 replicon RNA encoding the Renilla luciferase reporter indicated that all four motifs and the conserved sequence 2 (CS2) element within the 3'-DB are important for replication. However, for translation, mutation of TL1 alone does not have any effect; TL2 mutation has only a modest effect in translation, but translation is reduced by ∼60% in the TL1/TL2 double mutant, indicating that TL1 exhibits a cooperative synergy with TL2 in translation. Despite the variable contributions of individual TL and PK motifs in translation, WT levels are achieved when the complementarity between TL1/PK2 and TL2/PK1 is maintained even under conditions of inhibition of the translation initiation factor 4E function mediated by LY294002 via a noncanonical pathway. Taken together, our results indicate that the cis-acting RNA elements in the core region of DENV2 RNA that include two DB structures are required not only for RNA replication but also for optimal translation.
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Affiliation(s)
- Mark Manzano
- From the Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, D. C. 20057
| | - Erin D. Reichert
- From the Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, D. C. 20057
| | - Stephanie Polo
- the Center for Biologics Evaluation and Review, Food and Drug Administration, Bethesda, Maryland 20892
| | - Barry Falgout
- the Center for Biologics Evaluation and Review, Food and Drug Administration, Bethesda, Maryland 20892
| | | | - Bruce A. Shapiro
- the Center for Cancer Research Nanobiology Program, NCI-Frederick, National Institutes of Health, Frederick, Maryland 21702
| | - Radhakrishnan Padmanabhan
- From the Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, D. C. 20057
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31
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Tuplin A, Evans DJ, Buckley A, Jones IM, Gould EA, Gritsun TS. Replication enhancer elements within the open reading frame of tick-borne encephalitis virus and their evolution within the Flavivirus genus. Nucleic Acids Res 2011; 39:7034-48. [PMID: 21622960 PMCID: PMC3303483 DOI: 10.1093/nar/gkr237] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We provide experimental evidence of a replication enhancer element (REE) within the capsid gene of tick-borne encephalitis virus (TBEV, genus Flavivirus). Thermodynamic and phylogenetic analyses predicted that the REE folds as a long stable stem–loop (designated SL6), conserved among all tick-borne flaviviruses (TBFV). Homologous sequences and potential base pairing were found in the corresponding regions of mosquito-borne flaviviruses, but not in more genetically distant flaviviruses. To investigate the role of SL6, nucleotide substitutions were introduced which changed a conserved hexanucleotide motif, the conformation of the terminal loop and the base-paired dsRNA stacking. Substitutions were made within a TBEV reverse genetic system and recovered mutants were compared for plaque morphology, single-step replication kinetics and cytopathic effect. The greatest phenotypic changes were observed in mutants with a destabilized stem. Point mutations in the conserved hexanucleotide motif of the terminal loop caused moderate virus attenuation. However, all mutants eventually reached the titre of wild-type virus late post-infection. Thus, although not essential for growth in tissue culture, the SL6 REE acts to up-regulate virus replication. We hypothesize that this modulatory role may be important for TBEV survival in nature, where the virus circulates by non-viraemic transmission between infected and non-infected ticks, during co-feeding on local rodents.
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Affiliation(s)
- A Tuplin
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, Cranfield Health, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
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32
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Alcaraz-Estrada SL, Yocupicio-Monroy M, del Angel RM. Insights into dengue virus genome replication. Future Virol 2010. [DOI: 10.2217/fvl.10.49] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Since many antiviral drugs are designed to interfere with viral genome replication, understanding this step in the viral replicative cycle has gained importance in recent years. Replication for many RNA viruses occurs in cellular compartments mainly originated from the production and reorganization of virus-induced membranes. Dengue virus translates, replicates and assembles new viral particles within virus-induced membranes from endoplasmic reticulum. In these compartments, all of the components required for replication are recruited, making the process efficient. In addition, membranes protect replication complexes from RNAases and proteases, and ultimately make them less visible to cellular defense sensors. Although several aspects in dengue virus replication are known, many others are yet to be understood. This article aims to summarize the advances in the understanding of dengue virus genome replication, highlighting the cis as well as trans elements that may have key roles in this process.
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Affiliation(s)
- Sofia Lizeth Alcaraz-Estrada
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Av. IPN 2508. Col. San Pedro Zacatenco, México, D.F. C.P. 07360
| | - Martha Yocupicio-Monroy
- Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México, México, D.F. México
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33
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Chausov EV, Ternovoi VA, Protopopova EV, Kononova JV, Konovalova SN, Pershikova NL, Romanenko VN, Ivanova NV, Bolshakova NP, Moskvitina NS, Loktev VB. Variability of the tick-borne encephalitis virus genome in the 5' noncoding region derived from ticks Ixodes persulcatus and Ixodes pavlovskyi in Western Siberia. Vector Borne Zoonotic Dis 2010; 10:365-75. [PMID: 19877811 DOI: 10.1089/vbz.2009.0064] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
We report the prevalence of Siberian and Far Eastern subtypes of tick-borne encephalitis virus (TBEV) in Ixodes persulcatus and Ix. pavlovskyi ticks collected in Tomsk and its suburbs during 2006-2008. The TBEV was detected in 5.7% ticks collected in the city, where Ix. pavlovskyi ticks were dominated and 7.5% ticks from suburban foci with prevalence Ix. persulcatus ticks. Genotyping of the virus showed that Siberian subtype (89.5%) is predominant in individual ticks of Tomsk suburbs; however, the proportion of Far Eastern subtype in two urban sites reached 47%. Phylogenetic analysis demonstrated that Siberian subtype variants from individual ticks were quite divergent and original. Only one subclade was found to be similar to Zausaev strain of TBEV, which is the etiological agent of lethal chronic form of tick-borne encephalitis infection. The average level of homology of 5' noncoding region (5'-NCR) of TBEV in the individual ticks was 95% for Far Eastern subtype and 89% for Siberian subtype of TBEV. Multiple substitutions in 5'-NCR were found in viral RNA derived from individual ticks. The A2 and C1 elements of Y-shaped structure and putative site for viral RNA polymerase were most variable regions for TBEV 5'-NCR. The B1 and B2 elements and the start codon were practically conserved. The viral RNA from three TBEV-infected pig kidney embryo cells after three passages (out of 21 polymerase chain reaction-positive ticks) were found to multiple substitutions in 5'-NCR in comparison with viral RNA from individual parent tick. However, these three variants did not replicate efficiently in pig kidney embryo cells that may be connected with a considerable modification of Y-shaped structure of 5'-NCR. The efficiently replicating isolate Kolarovo had only seven substitutions in the 5'-NCR and typical Y-shaped structure for Siberian subtype of TBEV. Our data support the idea that hypervariability of the 5'-NCR reflects viral strategy to select the fittest RNA molecule for productive viral infection in mammalian and tick cells.
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Affiliation(s)
- Eugene V Chausov
- State Research Center of Virology and Biotechnology "Vector ," Koltsovo, Novosibirsk Region, Russia
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Anthony SJ, Darpel KE, Maan S, Sutton G, Attoui H, Mertens PPC. The evolution of two homologues of the core protein VP6 of epizootic haemorrhagic disease virus (EHDV), which correspond to the geographical origin of the virus. Virus Genes 2009; 40:67-75. [PMID: 19830536 DOI: 10.1007/s11262-009-0410-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Accepted: 09/30/2009] [Indexed: 11/25/2022]
Abstract
Epizootic haemorrhagic disease virus is a 10-segmented, double-stranded RNA virus. When these ten segments of dsRNA are run on 1% agarose, eastern (Australia, Japan) and western (North America, Africa, Middle-East) strains of the virus can be separated phenotypically based on the migration of genome segments 7-9. In western strains, segments 7-9 are roughly the same size and co-migrate as a single RNA band. In eastern strains, segment 9 is smaller, so while segments 7 and 8 co-migrate, the segment 9 RNA runs faster than its western homologue. Translation experiments demonstrated that these two segment 9 homologues are both functional and produce proteins (VP6) of different sizes-something that has not been reported in any other orbivirus species to date. Sequence analysis suggests that eastern and western versions of segment 9 (VP6) have likely evolved as a response to adaptive selection in different geographical regions via gene duplication and subsequent mutation. These significant findings are considered unusual given the conserved nature of VP6 and its presumed role as the viral helicase. It is not currently known what the biological relevance of each homologue is to the virus.
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Affiliation(s)
- S J Anthony
- Vector-Borne Diseases Program, Institute for Animal Health, Ash Road, Pirbright, Surrey, GU24 0NF, UK.
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35
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3' cis-acting elements that contribute to the competence and efficiency of Japanese encephalitis virus genome replication: functional importance of sequence duplications, deletions, and substitutions. J Virol 2009; 83:7909-30. [PMID: 19494005 DOI: 10.1128/jvi.02541-08] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The positive-strand RNA genome of Japanese encephalitis virus (JEV) terminates in a highly conserved 3'-noncoding region (3'NCR) of six domains (V, X, I, II-1, II-2, and III in the 5'-to-3' direction). By manipulating the JEV genomic RNA, we have identified important roles for RNA elements present within the 574-nucleotide 3'NCR in viral replication. The two 3'-proximal domains (II-2 and III) were sufficient for RNA replication and virus production, whereas the remaining four (V, X, I, and II-1) were dispensable for RNA replication competence but required for maximal replication efficiency. Surprisingly, a lethal mutant lacking all of the 3'NCR except domain III regained viability through pseudoreversion by duplicating an 83-nucleotide sequence from the 3'-terminal region of the viral open reading frame. Also, two viable mutants displayed severe genetic instability; these two mutants rapidly developed 12 point mutations in domain II-2 in the mutant lacking domains V, X, I, and II-1 and showed the duplication of seven upstream sequences of various sizes at the junction between domains II-1 and II-2 in the mutant lacking domains V, X, and I. In all cases, the introduction of these spontaneous mutations led to an increase in RNA production that paralleled the level of protein accumulation and virus yield. Interestingly, the mutant lacking domains V, X, I, and II-1 was able to replicate in hamster BHK-21 and human neuroblastoma SH-SY5Y cells but not in mosquito C6/36 cells, indicating a cell type-specific restriction of its viral replication. Thus, our findings provide the basis for a detailed map of the 3' cis-acting elements in JEV genomic RNA, which play an essential role in viral replication. They also provide experimental evidence for the function of 3' direct repeat sequences and suggest possible mechanisms for the emergence of these sequences in the 3'NCR of JEV and perhaps in other flaviviruses.
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36
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Mitzel DN, Best SM, Masnick MF, Porcella SF, Wolfinbarger JB, Bloom ME. Identification of genetic determinants of a tick-borne flavivirus associated with host-specific adaptation and pathogenicity. Virology 2008; 381:268-76. [PMID: 18823640 DOI: 10.1016/j.virol.2008.08.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 08/05/2008] [Accepted: 08/19/2008] [Indexed: 01/12/2023]
Abstract
Tick-borne flaviviruses are maintained in nature in an enzootic cycle involving a tick vector and a vertebrate host. Thus, the virus replicates in two disparate hosts, each providing selective pressures that can influence virus replication and pathogenicity. To identify viral determinants associated with replication in the individual hosts, plaque purified Langat virus (TP21pp) was adapted to growth in mouse or tick cell lines to generate two virus variants, MNBp20 and ISEp20, respectively. Virus adaptation to mouse cells resulted in four amino acid changes in MNBp20 relative to TP21pp, occurring in E, NS4A and NS4B. A comparison between TP21pp and ISEp20 revealed three amino acid modifications in M, NS3 and NS4A of ISEp20. ISEp20, but not MNBp20, was attenuated following intraperitoneal inoculation of mice. Following isolation from mice brains, additional mutations reproducibly emerged in E and NS3 of ISEp20 that were possibly compensatory for the initial adaptation to tick cells. Thus, our data implicate a role for E, M, NS3, NS4A and NS4B in host adaptation and pathogenicity of tick-borne flaviviruses.
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Affiliation(s)
- Dana N Mitzel
- Laboratory of Virology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT 59840, USA.
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37
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Johnson N, Freuling C, Marston DA, Tordo N, Fooks AR, Müller T. Identification of European bat lyssavirus isolates with short genomic insertions. Virus Res 2007; 128:140-3. [PMID: 17521764 DOI: 10.1016/j.virusres.2007.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Revised: 04/05/2007] [Accepted: 04/06/2007] [Indexed: 11/22/2022]
Abstract
Molecular typing has consistently identified European bat lyssaviruses from Germany as EBLV type 1a (EBLV-1a). This report confirms the presence of the closely related EBLV-1b in southern Germany, a group previously reported from The Netherlands, France and Spain. Furthermore, two of three German EBLV-1b isolates contain a 6 base pair insertion within the 3' untranslated region (UTR) of the nucleoprotein gene. This feature was shared with a third EBLV-1b isolate from a region of France adjacent to the French-German border. Further investigation revealed a two base pair insertion in a single isolate of EBLV-2 at the same genomic location. Although the length of the nucleoprotein gene 3'UTRs do vary between lyssavirus genotypes, such insertions have not been recorded within genotypes and could be the result of duplications within the nucleoprotein mRNA transcript polyadenylation signal.
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Affiliation(s)
- Nicholas Johnson
- Rabies and Wildlife Zoonoses Group, WHO Collaborating Centre for the Characterization of Rabies and Rabies-Related Viruses, Veterinary Laboratories Agency, Weybridge, Woodham Lane, Addlestone, Surrey KT15 3NB, UK.
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38
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Appaiahgari MB, Vrati S. DNAzyme-mediated inhibition of Japanese encephalitis virus replication in mouse brain. Mol Ther 2007; 15:1593-9. [PMID: 17579579 DOI: 10.1038/sj.mt.6300231] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Japanese encephalitis virus (JEV) is an arthropod-borne flavivirus with a single-stranded RNA genome containing non-coding regions (NCRs) at its 5' and 3'-ends. The NCRs have flavivirus-conserved sequences that are important for virus replication. Here we describe DNAzymes (Dzs) that cleave the RNA sequence of the 3'-NCR of JEV genome in vitro. The nuclease-resistant Dzs, containing phosphorothioate linkages, were efficiently taken up by mouse neuronal and glial cells, and addition of a continuous stretch of 10 guanosine residues (poly-(G)(10)) to the 3'-end of a Dz led to its enhanced delivery to cells containing scavenger receptors (ScRs). These novel Dzs inhibited JEV replication in cultured mouse cells of neuronal and macrophage origin. JEV is a neurotropic virus that actively replicates in mouse brain. Here we show that intra-cerebral (i.c.) administration of a poly-(G)(10)-tethered, phosphorothioated Dz in JEV-infected mice led to more than 99.99% inhibition of virus replication in brain, resulting in a dose-dependent extended lifespan or complete recovery of the infected animals. This is the first report of in vivo application of a Dz to control a virus infection in an animal model.
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39
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Hughes AL, Piontkivska H, Foppa I. Rapid fixation of a distinctive sequence motif in the 3' noncoding region of the clade of West Nile virus invading North America. Gene 2007; 399:152-61. [PMID: 17587514 PMCID: PMC2268991 DOI: 10.1016/j.gene.2007.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Revised: 05/14/2007] [Accepted: 05/15/2007] [Indexed: 11/16/2022]
Abstract
Phylogenetic analysis of complete genomes of West Nile virus (WNV) by a variety of methods supported the hypothesis that North American isolates of WNV constitute a monophyletic group, together with an isolate from Israel and one from Hungary. We used ancestral sequence reconstruction in order to obtain evidence for evolutionary changes that might be correlated with increased virulence in this clade (designated the N.A. clade). There was one amino acid change (I-->T at residue 356 of the NS3 protein) that occurred in the ancestor of the N.A. clade and remained conserved in all N.A. clade genomes analyzed. There were four changes in the upstream portion of the 3' noncoding region (the AT-enriched region) that occurred in the ancestor of the N.A. clade and remained conserved in all N.A. clade genomes analyzed, changes predicted to alter RNA secondary structure. The AT-enriched region showed a higher rate of substitution in the branch ancestral to the N.A. clade, relative to polymorphism, than did the remainder of the noncoding regions, synonymous sites in coding regions, or nonsynonymous sites in coding regions. The high rate of occurrence of fixed nucleotide substitutions in this region suggests that positive Darwinian selection may have acted on this portion of the 3'NCR and that these fixed changes, possibly in concert with the amino acid change in NS3, may underlie phenotypic effects associated with increased virulence in North American WNV.
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Affiliation(s)
- Austin L Hughes
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, United States.
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40
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Gritsun TS, Gould EA. Origin and evolution of 3'UTR of flaviviruses: long direct repeats as a basis for the formation of secondary structures and their significance for virus transmission. Adv Virus Res 2007; 69:203-48. [PMID: 17222695 DOI: 10.1016/s0065-3527(06)69005-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The 3' untranslated regions (3'UTRs) of flaviviruses are reviewed and analyzed in relation to short sequences conserved as direct repeats (DRs). Previously, alignments of the 3'UTRs have been constructed for three of the four recognized flavivirus groups, namely mosquito-borne, tick-borne, and nonclassified flaviviruses (MBFV, TBFV, and NCFV, respectively). This revealed (1) six long repeat sequences (LRSs) in the 3'UTR and open-reading frame (ORF) of the TBFV, (2) duplication of the 3'UTR of the NCFV by intramolecular recombination, and (3) the possibility of a common origin for all DRs within the MBFV. We have now extended this analysis and review it in the context of all previous published analyses. This has been achieved by constructing a robust alignment between all flaviviruses using the published DRs and secondary RNA structures as "anchors" to reveal additional homologies along the 3'UTR. This approach identified nucleotide regions within the MBFV, NKV (no-known vector viruses), and NCFV 3'UTRs that are homologous to different LRSs in the TBFV 3'UTR and ORF. The analysis revealed that some of the DRs and secondary RNA structures described individually within each flavivirus group share common evolutionary origins. The 3'UTR of flaviviruses, and possibly the ORF, therefore probably evolved through multiple duplication of an RNA domain, homologous to the LRS previously identified only in the TBFV. The short DRs in all virus groups appear to represent the evolutionary remnants of these domains rather than resulting from new duplications. The relevance of these flavivirus DRs to evolution, diversity, 3'UTR enhancer function, and virus transmission is reviewed.
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Affiliation(s)
- T S Gritsun
- Centre for Ecology and Hydrology, Oxford, 0X1 3SR, United Kingdom
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41
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Direct repeats in the flavivirus 3' untranslated region; a strategy for survival in the environment? Virology 2006; 358:258-65. [PMID: 17067651 DOI: 10.1016/j.virol.2006.09.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 09/07/2006] [Accepted: 09/12/2006] [Indexed: 11/30/2022]
Abstract
Previously, direct repeats (DRs) of 20-70 nucleotides were identified in the 3' untranslated regions (3'UTR) of flavivirus sequences. To address their functional significance, we have manually generated a pan-flavivirus 3'UTR alignment and correlated it with the corresponding predicted RNA secondary structures. This approach revealed that intra-group-conserved DRs evolved from six long repeated sequences (LRSs) which, as approximately 200-nucleotide domains were preserved only in the genomes of the slowly evolving tick-borne flaviviruses. We propose that short DRs represent the evolutionary remnants of LRSs rather than distinct molecular duplications. The relevance of DRs to virus replication enhancer function, and thus survival, is discussed.
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