1
|
Bai Y, Lei H, Song W, Shin SC, Wang J, Xiao B, Koçer ZA, Song MS, Webster R, Webby RJ, Wong SS, Zanin M. Amino acids in the polymerase complex of shorebird-isolated H1N1 influenza virus impact replication and host-virus interactions in mammalian models. Emerg Microbes Infect 2024; 13:2332652. [PMID: 38517705 PMCID: PMC11018082 DOI: 10.1080/22221751.2024.2332652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 03/15/2024] [Indexed: 03/24/2024]
Abstract
A diverse population of avian influenza A viruses (AIVs) are maintained in wild birds and ducks yet the zoonotic potential of AIVs in these environmental reservoirs and the host-virus interactions involved in mammalian infection are not well understood. In studies of a group of subtype H1N1 AIVs isolated from migratory wild birds during surveillance in North America, we previously identified eight amino acids in the polymerase genes PB2 and PB1 that were important for the transmissibility of these AIVs in a ferret model of human influenza virus transmission. In this current study we found that PB2 containing amino acids associated with transmissibility at 67, 152, 199, 508, and 649 and PB1 at 298, 642, and 667 were associated with more rapid viral replication kinetics, greater infectivity, more active polymerase complexes and greater kinetics of viral genome replication and transcription. Pathogenicity in the mouse model was also impacted, evident as greater weight loss and lung pathology associated with greater inflammatory lung cytokine expression. Further, these AIVs all contained the avian-type amino acids of PB2-E627, D701, G590, Q591 and T271. Therefore, our study provides novel insights into the role of the AIV polymerase complex in the zoonotic transmission of AIVs in mammals.
Collapse
Affiliation(s)
- Yaqin Bai
- HKU-Pasteur Research Pole, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Guangzhou Medical University, Guangzhou, People’s Republic of China
- State Key Laboratory of Respiratory Diseases, Guangzhou, People’s Republic of China
| | - Hui Lei
- School of Public Health, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Centre for Immunology & Infection, Hong Kong SAR, People's Republic of China
| | - Wenjun Song
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, People’s Republic of China
| | | | - Jiaqi Wang
- Guangzhou Medical University, Guangzhou, People’s Republic of China
- State Key Laboratory of Respiratory Diseases, Guangzhou, People’s Republic of China
| | - Biying Xiao
- Guangzhou Medical University, Guangzhou, People’s Republic of China
- State Key Laboratory of Respiratory Diseases, Guangzhou, People’s Republic of China
| | - Zeynep A. Koçer
- Emerging Viral Diseases Laboratory, Izmir Biomedicine and Genome Center, Izmir, Türkiye
- Department of Biomedicine and Health Technologies, Izmir International Biomedicine and Genome Institute, Izmir, Türkiye
| | - Min-Suk Song
- Department of Microbiology, Chungbuk National University Medical School, Chungbuk, Korea
| | - Robert Webster
- Department of Host-Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Richard J. Webby
- Department of Host-Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Sook-San Wong
- HKU-Pasteur Research Pole, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Mark Zanin
- School of Public Health, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Centre for Immunology & Infection, Hong Kong SAR, People's Republic of China
| |
Collapse
|
2
|
Wang X, Tang XE, Zheng H, Gao R, Lu X, Yang W, Zhou L, Chen Y, Gu M, Hu J, Liu X, Hu S, Liu K, Liu X. Amino acid mutations PB1-V719M and PA-N444D combined with PB2-627K contribute to the pathogenicity of H7N9 in mice. Vet Res 2024; 55:86. [PMID: 38970119 PMCID: PMC11227215 DOI: 10.1186/s13567-024-01342-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 06/14/2024] [Indexed: 07/07/2024] Open
Abstract
H7N9 subtype avian influenza viruses (AIVs) cause 1567 human infections and have high mortality, posing a significant threat to public health. Previously, we reported that two avian-derived H7N9 isolates (A/chicken/Eastern China/JTC4/2013 and A/chicken/Eastern China/JTC11/2013) exhibit different pathogenicities in mice. To understand the genetic basis for the differences in virulence, we constructed a series of mutant viruses based on reverse genetics. We found that the PB2-E627K mutation alone was not sufficient to increase the virulence of H7N9 in mice, despite its ability to enhance polymerase activity in mammalian cells. However, combinations with PB1-V719M and/or PA-N444D mutations significantly enhanced H7N9 virulence. Additionally, these combined mutations augmented polymerase activity, thereby intensifying virus replication, inflammatory cytokine expression, and lung injury, ultimately increasing pathogenicity in mice. Overall, this study revealed that virulence in H7N9 is a polygenic trait and identified novel virulence-related residues (PB2-627K combined with PB1-719M and/or PA-444D) in viral ribonucleoprotein (vRNP) complexes. These findings provide new insights into the molecular mechanisms underlying AIV pathogenesis in mammals, with implications for pandemic preparedness and intervention strategies.
Collapse
Affiliation(s)
- Xiaoquan Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Xin-En Tang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
| | - Huafen Zheng
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
| | - Ruyi Gao
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Xiaolong Lu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Wenhao Yang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Le Zhou
- Yangzhou Center for Disease Control and Prevention, Yangzhou, 225009, China
| | - Yu Chen
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Min Gu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Jiao Hu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Xiaowen Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Shunlin Hu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China
| | - Kaituo Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China.
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China.
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China.
| | - Xiufan Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, China.
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, 225009, China.
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, 225009, China.
| |
Collapse
|
3
|
Xue L, Chang T, Li Z, Wang C, Zhao H, Li M, Tang P, Wen X, Yu M, Wu J, Bao X, Wang X, Gong P, He J, Chen X, Xiong X. Cryo-EM structures of Thogoto virus polymerase reveal unique RNA transcription and replication mechanisms among orthomyxoviruses. Nat Commun 2024; 15:4620. [PMID: 38816392 PMCID: PMC11139864 DOI: 10.1038/s41467-024-48848-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 05/13/2024] [Indexed: 06/01/2024] Open
Abstract
Influenza viruses and thogotoviruses account for most recognized orthomyxoviruses. Thogotoviruses, exemplified by Thogoto virus (THOV), are capable of infecting humans using ticks as vectors. THOV transcribes mRNA without the extraneous 5' end sequences derived from cap-snatching in influenza virus mRNA. Here, we report cryo-EM structures to characterize THOV polymerase RNA synthesis initiation and elongation. The structures demonstrate that THOV RNA transcription and replication are able to start with short dinucleotide primers and that the polymerase cap-snatching machinery is likely non-functional. Triggered by RNA synthesis, asymmetric THOV polymerase dimers can form without the involvement of host factors. We confirm that, distinctive from influenza viruses, THOV-polymerase RNA synthesis is weakly dependent of the host factors ANP32A/B/E in human cells. This study demonstrates varied mechanisms in RNA synthesis and host factor utilization among orthomyxoviruses, providing insights into the mechanisms behind thogotoviruses' broad-infectivity range.
Collapse
Affiliation(s)
- Lu Xue
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Tiancai Chang
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Zimu Li
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- Guangzhou National Laboratory, Guangzhou, Guangdong, China
| | - Chenchen Wang
- College of Medicine, Southern University of Science and Technology, Shenzhen, China
| | - Heyu Zhao
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Mei Li
- Guangzhou National Laboratory, Guangzhou, Guangdong, China
| | - Peng Tang
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xin Wen
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mengmeng Yu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jiqin Wu
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei, China
| | - Xichen Bao
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xiaojun Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Peng Gong
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei, China
| | - Jun He
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xinwen Chen
- Guangzhou National Laboratory, Guangzhou, Guangdong, China.
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei, China.
| | - Xiaoli Xiong
- State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
| |
Collapse
|
4
|
Kou Z, Fan X, Li J, Shao Z, Qiang X. Using amino acid features to identify the pathogenicity of influenza B virus. Infect Dis Poverty 2022; 11:50. [PMID: 35509019 PMCID: PMC9066401 DOI: 10.1186/s40249-022-00974-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/16/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Influenza B virus can cause epidemics with high pathogenicity, so it poses a serious threat to public health. A feature representation algorithm is proposed in this paper to identify the pathogenicity phenotype of influenza B virus. METHODS The dataset included all 11 influenza virus proteins encoded in eight genome segments of 1724 strains. Two types of features were hierarchically used to build the prediction model. Amino acid features were directly delivered from 67 feature descriptors and input into the random forest classifier to output informative features about the class label and probabilistic prediction. The sequential forward search strategy was used to optimize the informative features. The final features for each strain had low dimensions and included knowledge from different perspectives, which were used to build the machine learning model for pathogenicity identification. RESULTS The 40 signature positions were achieved by entropy screening. Mutations at position 135 of the hemagglutinin protein had the highest entropy value (1.06). After the informative features were directly generated from the 67 random forest models, the dimensions for class and probabilistic features were optimized as 4 and 3, respectively. The optimal class features had a maximum accuracy of 94.2% and a maximum Matthews correlation coefficient of 88.4%, while the optimal probabilistic features had a maximum accuracy of 94.1% and a maximum Matthews correlation coefficient of 88.2%. The optimized features outperformed the original informative features and amino acid features from individual descriptors. The sequential forward search strategy had better performance than the classical ensemble method. CONCLUSIONS The optimized informative features had the best performance and were used to build a predictive model so as to identify the phenotype of influenza B virus with high pathogenicity and provide early risk warning for disease control.
Collapse
Affiliation(s)
- Zheng Kou
- Institute of Computing Science and Technology, Guangzhou University, Guangzhou, 510006, China.
| | - Xinyue Fan
- Institute of Computing Science and Technology, Guangzhou University, Guangzhou, 510006, China
| | - Junjie Li
- Institute of Computing Science and Technology, Guangzhou University, Guangzhou, 510006, China
| | - Zehui Shao
- Institute of Computing Science and Technology, Guangzhou University, Guangzhou, 510006, China
| | - Xiaoli Qiang
- School of Computer Science and Cyber Engineering, Guangzhou University, Guangzhou, 510006, China.
| |
Collapse
|
5
|
Zhang M, Liu M, Bai S, Zhao C, Li Z, Xu J, Zhang X. Influenza A Virus-Host Specificity: An Ongoing Cross-Talk Between Viral and Host Factors. Front Microbiol 2021; 12:777885. [PMID: 34803997 PMCID: PMC8602901 DOI: 10.3389/fmicb.2021.777885] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/19/2021] [Indexed: 11/13/2022] Open
Abstract
One big threat from influenza A viruses (IAVs) is that novel viruses emerge from mutation alongside reassortment. Some of them have gained the capability to transmit into human from the avian reservoir. Understanding the molecular events and the involved factors in breaking the cross-species barrier holds important implication for the surveillance and prevention of potential influenza outbreaks. In this review, we summarize recent progresses, including several ground-breaking findings, in how the interaction between host and viral factors, exemplified by the PB2 subunit of the influenza virus RNA polymerase co-opting host ANP32 protein to facilitate transcription and replication of the viral genome, shapes the evolution of IAVs from host specificity to cross-species infection.
Collapse
Affiliation(s)
- Miaomiao Zhang
- Scientific Research Center, Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Shanghai Medical College, Fudan University, Shanghai, China.,Shanghai Veterinary Research Institute, Chinese Academic of Agricultural Sciences & Animal Influenza Virus Evolution and Pathogenesis Innovation Team of the Agricultural Science and Technology Innovation Team, Shanghai, China
| | - Mingbin Liu
- Scientific Research Center, Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Shanghai Medical College, Fudan University, Shanghai, China
| | - Shimeng Bai
- Scientific Research Center, Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chen Zhao
- Scientific Research Center, Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zejun Li
- Shanghai Veterinary Research Institute, Chinese Academic of Agricultural Sciences & Animal Influenza Virus Evolution and Pathogenesis Innovation Team of the Agricultural Science and Technology Innovation Team, Shanghai, China
| | - Jianqing Xu
- Scientific Research Center, Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaoyan Zhang
- Scientific Research Center, Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Shanghai Medical College, Fudan University, Shanghai, China
| |
Collapse
|
6
|
Waters K, Gao C, Ykema M, Han L, Voth L, Tao YJ, Wan XF. Triple reassortment increases compatibility among viral ribonucleoprotein genes of contemporary avian and human influenza A viruses. PLoS Pathog 2021; 17:e1009962. [PMID: 34618879 PMCID: PMC8525756 DOI: 10.1371/journal.ppat.1009962] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 10/19/2021] [Accepted: 09/20/2021] [Indexed: 12/21/2022] Open
Abstract
Compatibility among the influenza A virus (IAV) ribonucleoprotein (RNP) genes affects viral replication efficiency and can limit the emergence of novel reassortants, including those with potential pandemic risks. In this study, we determined the polymerase activities of 2,451 RNP reassortants among three seasonal and eight enzootic IAVs by using a minigenome assay. Results showed that the 2009 H1N1 RNP are more compatible with the tested enzootic RNP than seasonal H3N2 RNP and that triple reassortment increased such compatibility. The RNP reassortants among 2009 H1N1, canine H3N8, and avian H4N6 IAVs had the highest polymerase activities. Residues in the RNA binding motifs and the contact regions among RNP proteins affected polymerase activities. Our data indicates that compatibility among seasonal and enzootic RNPs are selective, and enzoosis of multiple strains in the animal-human interface can facilitate emergence of an RNP with increased replication efficiency in mammals, including humans.
Collapse
Affiliation(s)
- Kaitlyn Waters
- Missouri University Center for Influenza and Emerging Infectious Diseases, University of Missouri, Columbia, Missouri, United States of America
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, Missouri, United States of America
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, Mississippi, United States of America
| | - Cheng Gao
- Missouri University Center for Influenza and Emerging Infectious Diseases, University of Missouri, Columbia, Missouri, United States of America
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Electrical Engineering & Computer Science, College of Engineering, University of Missouri, Columbia, Missouri, United States of America
| | - Matthew Ykema
- Department of BioSciences, Rice University, Houston, Texas, United States of America
| | - Lei Han
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, Mississippi, United States of America
| | - Lynden Voth
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, Missouri, United States of America
| | - Yizhi Jane Tao
- Department of BioSciences, Rice University, Houston, Texas, United States of America
| | - Xiu-Feng Wan
- Missouri University Center for Influenza and Emerging Infectious Diseases, University of Missouri, Columbia, Missouri, United States of America
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, Missouri, United States of America
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, Mississippi, United States of America
- Department of Electrical Engineering & Computer Science, College of Engineering, University of Missouri, Columbia, Missouri, United States of America
- * E-mail:
| |
Collapse
|
7
|
Abstract
Influenza polymerase (FluPol) plays a key role in the viral infection cycle by transcribing and replicating the viral genome. FluPol is a multifunctional, heterotrimeric enzyme with cap-binding, endonuclease, RNA-dependent RNA polymerase and polyadenylation activities. It performs its functions in the context of the viral ribonucleoprotein particle (RNP), wherein the template viral RNA is coated by multiple copies of viral nucleoprotein. Moreover, it interacts with a number of host proteins that are essential cofactors and, consequently, adaptive mutations in the polymerase are required for crossing the avian-human species barrier. In this review, we show how mechanistic understanding of how FluPol performs its multiple functions has greatly advanced over the last decade through determination of high-resolution structures by X-ray crystallography and cryo-electron microscopy. These have revealed not only the detailed architecture of FluPol but highlighted the remarkably conformational flexibility that is inherent to its functioning as a dynamic RNA synthesis machine. Structural studies are also underpinning current attempts to develop next-generation anti-influenza drugs that directly target FluPol.
Collapse
Affiliation(s)
- Joanna M Wandzik
- European Molecular Biology Laboratory, Grenoble 38042-Cedex 9, France
| | - Tomas Kouba
- European Molecular Biology Laboratory, Grenoble 38042-Cedex 9, France
| | - Stephen Cusack
- European Molecular Biology Laboratory, Grenoble 38042-Cedex 9, France
| |
Collapse
|
8
|
Horio Y, Shichiri M, Isegawa Y. Development of a method for evaluating the mRNA transcription activity of influenza virus RNA-dependent RNA polymerase through real-time reverse transcription polymerase chain reaction. Virol J 2021; 18:177. [PMID: 34454523 PMCID: PMC8401337 DOI: 10.1186/s12985-021-01644-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/18/2021] [Indexed: 11/17/2022] Open
Abstract
Background The development of an influenza RNA-dependent RNA polymerase (RdRp) inhibitor is required; therefore, a method for evaluating the activity of influenza RdRp needs to be developed. The current method uses an ultracentrifuge to separate viral particles and quantifies RdRp activity with radioisotope-labeled nucleosides, such as 32P-GTP. This method requires special equipment and radioisotope management, so it cannot be implemented in all institutions. We have developed a method to evaluate the mRNA transcription activity of RdRp without using ultracentrifugation and radioisotopes. Results RdRp was extracted from viral particles that were purified from the culture supernatant using anionic polymer-coated magnetic beads that can concentrate influenza virus particles from the culture supernatant in approximately 30 min. A strand-specific real-time reverse transcription polymerase chain reaction (RT-PCR) method was developed based on reverse transcription using tagged primers. RT primers were designed to bind to a sequence near the 3' end of mRNA containing a poly A tail for specific recognition of the mRNA, with an 18-nucleotide tag attached to the 5' end of the sequence. The RT reaction was performed with this tagged RT primer, and the amount of mRNA was analyzed using real-time qPCR. Real-time qPCR using the tag sequence as the forward primer and a segment-specific reverse primer ensured the specificity for quantifying the mRNA of segments 1, 4, and 5. The temperature, reaction time, and Mg2+ concentration were determined to select the optimum conditions for in vitro RNA synthesis by RdRp, and the amount of synthesized mRNAs of segments 1, 4, and 5 was determined with a detection sensitivity of 10 copies/reaction. In addition, mRNA synthesis was inhibited by ribavirin triphosphate, an RdRp inhibitor, thus indicating the usefulness of this evaluation method for screening RdRp inhibitors. Conclusion This method makes it possible to analyze the RdRp activity even in a laboratory where ultracentrifugation and radioisotopes cannot be used. This novel method for measuring influenza virus polymerase activity will further promote research to identify compounds that inhibit viral mRNA transcription activity of RdRp. Supplementary Information The online version contains supplementary material available at 10.1186/s12985-021-01644-7.
Collapse
Affiliation(s)
- Yuka Horio
- Department of Food Sciences and Nutrition, Mukogawa Women's University, 6-46 Ikebiraki, Nishinomiya, Hyogo, 663-8558, Japan.,Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka, 563-8577, Japan
| | - Mototada Shichiri
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka, 563-8577, Japan. .,DBT-AIST International Laboratory for Advanced Biomedicine (DAILAB), 1-1-1 Higashi, Tsukuba-shi, Ibaraki, 305-8562, Japan.
| | - Yuji Isegawa
- Department of Food Sciences and Nutrition, Mukogawa Women's University, 6-46 Ikebiraki, Nishinomiya, Hyogo, 663-8558, Japan. .,Institute for Biosciences, Mukogawa Women's University, 6-46 Ikebiraki, Nishinomiya, Hyogo, 663-8558, Japan.
| |
Collapse
|
9
|
Weis S, te Velthuis AJW. Influenza Virus RNA Synthesis and the Innate Immune Response. Viruses 2021; 13:v13050780. [PMID: 33924859 PMCID: PMC8146608 DOI: 10.3390/v13050780] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 04/25/2021] [Accepted: 04/25/2021] [Indexed: 12/25/2022] Open
Abstract
Infection with influenza A and B viruses results in a mild to severe respiratory tract infection. It is widely accepted that many factors affect the severity of influenza disease, including viral replication, host adaptation, innate immune signalling, pre-existing immunity, and secondary infections. In this review, we will focus on the interplay between influenza virus RNA synthesis and the detection of influenza virus RNA by our innate immune system. Specifically, we will discuss the generation of various RNA species, host pathogen receptors, and host shut-off. In addition, we will also address outstanding questions that currently limit our knowledge of influenza virus replication and host adaption. Understanding the molecular mechanisms underlying these factors is essential for assessing the pandemic potential of future influenza virus outbreaks.
Collapse
|
10
|
Zhou L, Feng Z, Liu J, Chen Y, Yang L, Liu S, Li X, Gao R, Zhu W, Wang D, Shu Y. A single N342D substitution in Influenza B Virus NA protein determines viral pathogenicity in mice. Emerg Microbes Infect 2021; 9:1853-1863. [PMID: 32746754 PMCID: PMC7473139 DOI: 10.1080/22221751.2020.1806005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Influenza B virus (IBV) is one of the most important human respiratory viruses: it causes approximately one-third of the global influenza-related disease burden each year. However, compared with the several pathogenicity-related molecular markers that have been identified for influenza A virus (IAV), little is known about potential IBV pathogenicity-related markers. Here, although the IBV strain B/Anhui-Tunxi/1528/2014 (AH1528/14) exhibited a more efficient replication ability in vitro and higher pathogenicity in vivo compared with IBV strain B/Anhui-Baohe/127/2015 (AH127/15), only three amino acids differences (HAA390E, NAN342D and PB1V212I) were observed among their full genomes. The contributions of each amino acid difference to the virus pathogenicity were further investigated. Compared with the wild type IBV virus rAH127, the recombinant virus harbouring a single substitution of HAA390E had a similar phenotype, whereas the recombinant virus harbouring PB1V212I replicated to a moderately higher titre in both MDCK cells and in mice. Notably, the virus harbouring NAN342D showed significantly better growth properties in MDCK cells and higher fatality rates in mice. In addition, the presence of NAN342D dramatically enhanced the viral neuraminidase activity. In conclusion, our study identified a novel IBV molecular marker, NAN342D, that could significantly increase the virulence of IBV in mice.
Collapse
Affiliation(s)
- Lijuan Zhou
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangdong, People's Republic of China.,National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Zhaomin Feng
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Jia Liu
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Yongkun Chen
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangdong, People's Republic of China
| | - Lei Yang
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Suli Liu
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangdong, People's Republic of China
| | - Xiyan Li
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Rongbao Gao
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Wenfei Zhu
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Dayan Wang
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Yuelong Shu
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangdong, People's Republic of China.,National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| |
Collapse
|
11
|
The Polarity of an Amino Acid at Position 1891 of Severe Fever with Thrombocytopenia Syndrome Virus L Protein Is Critical for the Polymerase Activity. Viruses 2020; 13:v13010033. [PMID: 33375489 PMCID: PMC7823514 DOI: 10.3390/v13010033] [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: 11/30/2020] [Revised: 12/20/2020] [Accepted: 12/23/2020] [Indexed: 11/30/2022] Open
Abstract
Severe fever with thrombocytopenia syndrome virus subclone B7 shows strong plaque formation and cytopathic effect induction compared with other subclones and the parental strain YG1. Compared to YG1 and the other subclones, only B7 possesses a single substitution in the L protein at the amino acid position 1891, in which N is changed to K (N1891K). In this study, we evaluate the effects of this mutation on L protein activity via a cell-based minigenome assay. Substitutions of N with basic amino acids (K or R) enhanced polymerase activity, while substitutions with an acidic amino acid (E) decreased this activity. Mutation to other neutral amino acids showed no significant effect on activity. These results suggest that the characteristic of the amino acid at position 1891 of the L protein are critical for its function, especially with respect to the charge status. Our data indicate that this C-terminal domain of the L protein may be crucial to its functions in genome transcription and viral replication.
Collapse
|
12
|
Escalera-Zamudio M, Golden M, Gutiérrez B, Thézé J, Keown JR, Carrique L, Bowden TA, Pybus OG. Parallel evolution in the emergence of highly pathogenic avian influenza A viruses. Nat Commun 2020; 11:5511. [PMID: 33139731 PMCID: PMC7608645 DOI: 10.1038/s41467-020-19364-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/12/2020] [Indexed: 01/30/2023] Open
Abstract
Parallel molecular evolution and adaptation are important phenomena commonly observed in viruses. Here, we exploit parallel molecular evolution to understand virulence evolution in avian influenza viruses (AIV). Highly-pathogenic AIVs evolve independently from low-pathogenic ancestors via acquisition of polybasic cleavage sites. Why some AIV lineages but not others evolve in this way is unknown. We hypothesise that the parallel emergence of highly-pathogenic AIV may be facilitated by permissive or compensatory mutations occurring across the viral genome. We combine phylogenetic, statistical and structural approaches to discover parallel mutations in AIV genomes associated with the highly-pathogenic phenotype. Parallel mutations were screened using a statistical test of mutation-phenotype association and further evaluated in the contexts of positive selection and protein structure. Our resulting mutational panel may help to reveal new links between virulence evolution and other traits, and raises the possibility of predicting aspects of AIV evolution.
Collapse
Affiliation(s)
| | - Michael Golden
- Department of Zoology, Oxford University, Parks Rd, Oxford, OX1 3PS, UK
| | | | - Julien Thézé
- Department of Zoology, Oxford University, Parks Rd, Oxford, OX1 3PS, UK
| | - Jeremy Russell Keown
- Division of Structural Biology, Wellcome Centre for Human Genetics, Oxford, OX3 7BN, UK
| | - Loic Carrique
- Division of Structural Biology, Wellcome Centre for Human Genetics, Oxford, OX3 7BN, UK
| | - Thomas A Bowden
- Division of Structural Biology, Wellcome Centre for Human Genetics, Oxford, OX3 7BN, UK
| | - Oliver G Pybus
- Department of Zoology, Oxford University, Parks Rd, Oxford, OX1 3PS, UK.
- Department of Pathobiology and Population Sciences, Royal Veterinary College, London, UK.
| |
Collapse
|
13
|
Carrique L, Fan H, Walker AP, Keown JR, Sharps J, Staller E, Barclay WS, Fodor E, Grimes JM. Host ANP32A mediates the assembly of the influenza virus replicase. Nature 2020; 587:638-643. [PMID: 33208942 PMCID: PMC7116770 DOI: 10.1038/s41586-020-2927-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 09/01/2020] [Indexed: 12/11/2022]
Abstract
Aquatic birds represent a vast reservoir from which new pandemic influenza A viruses can emerge1. Influenza viruses contain a negative-sense segmented RNA genome that is transcribed and replicated by the viral heterotrimeric RNA polymerase (FluPol) in the context of viral ribonucleoprotein complexes2,3. RNA polymerases of avian influenza A viruses (FluPolA) replicate viral RNA inefficiently in human cells because of species-specific differences in acidic nuclear phosphoprotein 32 (ANP32), a family of essential host proteins for FluPol activity4. Host-adaptive mutations, particularly a glutamic-acid-to-lysine mutation at amino acid residue 627 (E627K) in the 627 domain of the PB2 subunit, enable avian FluPolA to overcome this restriction and efficiently replicate viral RNA in the presence of human ANP32 proteins. However, the molecular mechanisms of genome replication and the interplay with ANP32 proteins remain largely unknown. Here we report cryo-electron microscopy structures of influenza C virus polymerase (FluPolC) in complex with human and chicken ANP32A. In both structures, two FluPolC molecules form an asymmetric dimer bridged by the N-terminal leucine-rich repeat domain of ANP32A. The C-terminal low-complexity acidic region of ANP32A inserts between the two juxtaposed PB2 627 domains of the asymmetric FluPolA dimer, suggesting a mechanism for how the adaptive PB2(E627K) mutation enables the replication of viral RNA in mammalian hosts. We propose that this complex represents a replication platform for the viral RNA genome, in which one of the FluPol molecules acts as a replicase while the other initiates the assembly of the nascent replication product into a viral ribonucleoprotein complex.
Collapse
Affiliation(s)
- Loïc Carrique
- Division of Structural Biology, University of Oxford, Oxford, UK
| | - Haitian Fan
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | | | - Jeremy R Keown
- Division of Structural Biology, University of Oxford, Oxford, UK
| | - Jane Sharps
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Ecco Staller
- Section of Molecular Virology, Imperial College London, London, UK
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Wendy S Barclay
- Section of Molecular Virology, Imperial College London, London, UK
| | - Ervin Fodor
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
| | - Jonathan M Grimes
- Division of Structural Biology, University of Oxford, Oxford, UK.
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, UK.
| |
Collapse
|
14
|
Szeto WC, Hsia HP, Tang YS, Shaw PC. Interaction between influenza A virus nucleoprotein and PB2 cap-binding domain is mediated by RNA. PLoS One 2020; 15:e0239899. [PMID: 32986763 PMCID: PMC7521707 DOI: 10.1371/journal.pone.0239899] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 09/15/2020] [Indexed: 12/02/2022] Open
Abstract
Influenza A virus controls replication and transcription of its genome through the tight regulation of interaction between the ribonucleoprotein (RNP) complex subunits. The helical scaffold of RNP is maintained by nucleoprotein (NP). Previous studies have revealed that NP interacts with both PB2 N-terminal and C-terminal regions, with both regions sharing similar affinity to NP as revealed in co-immunoprecipitation assay. Our work here suggests that the interaction between NP and PB2 N-terminal region lies in the cap-binding domain (residue 320-483). By co-immunoprecipitation assay, the interaction was found to involve RNA. On the other hand, the cap-binding activity was not essential in the interaction. As shown by the NHS pull-down assay, a specific RNA sequence was not required. Among the cap-binding domain, residues K331 and R332 of PB2 play a role in RNP function so that polymerase activity was reduced when these residues were mutated, while K331 was found to be more crucial in the NP interaction. Collectively, our findings suggest a new binding mode between NP and PB2 which was mediated by RNA, and such interaction may provide a novel interacting site for influenza drug development.
Collapse
Affiliation(s)
- Wun-Chung Szeto
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Ho-Pan Hsia
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Yun-Sang Tang
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Pang-Chui Shaw
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| |
Collapse
|
15
|
Elucidating the Interactions between Influenza Virus Polymerase and Host Factor ANP32A. J Virol 2020; 94:JVI.01353-19. [PMID: 31694956 PMCID: PMC7000967 DOI: 10.1128/jvi.01353-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 10/24/2019] [Indexed: 12/13/2022] Open
Abstract
Successful zoonotic transmission of influenza A virus into humans can lead to pandemics in an immunologically naive population. Host-encoded ANP32A proteins are required to support influenza A virus polymerase activity, and species differences in ANP32A can restrict the host range of influenza virus. Understanding how ANP32A proteins support the viral polymerase and how differences in ANP32A affect the ability of the polymerase to coopt these proteins will enhance our understanding of viral replication and species restriction as well as suggesting targeted antiviral approaches to treat influenza virus infection. The avian-origin influenza A virus polymerase is restricted in human cells. This restriction has been associated with species differences in host factor ANP32A. Avian ANP32A supports the activity of an avian-origin polymerase. However, the avian-origin polymerase is incompatible with human ANP32A. Avian ANP32A proteins harbor an additional 33 amino acids compared to human ANP32A proteins, which are crucial for their ability to support the avian-origin influenza virus polymerase. Here, we elucidate the interactions between ANP32A proteins and the influenza A virus polymerase using split luciferase complementation assays, coimmunoprecipitation, and in situ split Venus interaction assays. We show greater interaction of chicken ANP32A than human ANP32A with the viral polymerase and visualize these interactions in situ in the cell nucleus. We demonstrate that the 33 amino acids of chicken ANP32A and the PB2 627 domain of viral polymerase complex both contribute to this enhanced interaction. Finally, we show how these interactions are affected by the presence of viral RNA and the processivity of the polymerase, giving insights into the way that ANP32A might act during virus infection. IMPORTANCE Successful zoonotic transmission of influenza A virus into humans can lead to pandemics in an immunologically naive population. Host-encoded ANP32A proteins are required to support influenza A virus polymerase activity, and species differences in ANP32A can restrict the host range of influenza virus. Understanding how ANP32A proteins support the viral polymerase and how differences in ANP32A affect the ability of the polymerase to coopt these proteins will enhance our understanding of viral replication and species restriction as well as suggesting targeted antiviral approaches to treat influenza virus infection.
Collapse
|
16
|
Bi Z, Ye H, Wang X, Fang A, Yu T, Yan L, Zhou J. Insights into species-specific regulation of ANP32A on the mammalian-restricted influenza virus polymerase activity. Emerg Microbes Infect 2020; 8:1465-1478. [PMID: 31608791 PMCID: PMC6818127 DOI: 10.1080/22221751.2019.1676625] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The ANP32A is responsible for mammalian-restricted influenza virus polymerase activity. However, the mechanism of ANP32A modulation of polymerase activity remains poorly understood. Here, we report that chicken ANP32A (chANP32A) -X1 and -X2 stimulated mammalian-restricted PB2 627E polymerase activity in a dose-dependent manner. Distinct effects of ANP32A constructs suggested that the 180VK181 residues within chANP32A-X1 are necessary but not sufficient to stimulate PB2 627E polymerase activity. The PB2 N567D, T598V, A613V or F636L mutations promoted PB2 627E polymerase activity and chANP32A-X1 showed additive effects, providing further support that species-specific regulation of ANP32A might be only relevant with the PB2 E627K mutation. Rescue of cycloheximide-mediated inhibition showed that ANP32A is species-specific for modulation of vRNA but not mRNA and cRNA, demonstrating chANP32A-X1 compensated for defective cRNPs produced by PB2 627E virus in mammalian cells. The promoter mutations of cRNA enhanced the restriction of PB2 627E polymerase in mammalian cells, which could be restored by chANP32A-X1, indicating that ANP32A is likely to regulate the interaction of viral polymerase with RNA promoter. Coimmunoprecipitation showed that ANP32A did not affect the primary cRNPs assembly. We propose a model that chANP32A-X1 regulates PB2 627E polymerase for suitable interaction with cRNA promoter for vRNA replication.
Collapse
Affiliation(s)
- Zhenwei Bi
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Institute of Immunology and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing , People's Republic of China
| | - Hongliu Ye
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Institute of Immunology and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing , People's Republic of China
| | - Xingbo Wang
- MOA Key Laboratory of Animal Virology, Institute of Preventive Veterinary Sciences and Department of Veterinary Medicine, Zhejiang University , Hangzhou , People's Republic of China.,Collaborative innovation center and State Key laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, Zhejiang University , Hangzhou , People's Republic of China
| | - An Fang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Institute of Immunology and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing , People's Republic of China
| | - Tianqi Yu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Institute of Immunology and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing , People's Republic of China.,MOA Key Laboratory of Animal Virology, Institute of Preventive Veterinary Sciences and Department of Veterinary Medicine, Zhejiang University , Hangzhou , People's Republic of China.,Collaborative innovation center and State Key laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, Zhejiang University , Hangzhou , People's Republic of China
| | - Liping Yan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Institute of Immunology and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing , People's Republic of China
| | - Jiyong Zhou
- MOA Key Laboratory of Animal Virology, Institute of Preventive Veterinary Sciences and Department of Veterinary Medicine, Zhejiang University , Hangzhou , People's Republic of China.,Collaborative innovation center and State Key laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, Zhejiang University , Hangzhou , People's Republic of China
| |
Collapse
|
17
|
Suttie A, Deng YM, Greenhill AR, Dussart P, Horwood PF, Karlsson EA. Inventory of molecular markers affecting biological characteristics of avian influenza A viruses. Virus Genes 2019; 55:739-768. [PMID: 31428925 PMCID: PMC6831541 DOI: 10.1007/s11262-019-01700-z] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 08/09/2019] [Indexed: 12/20/2022]
Abstract
Avian influenza viruses (AIVs) circulate globally, spilling over into domestic poultry and causing zoonotic infections in humans. Fortunately, AIVs are not yet capable of causing sustained human-to-human infection; however, AIVs are still a high risk as future pandemic strains, especially if they acquire further mutations that facilitate human infection and/or increase pathogenesis. Molecular characterization of sequencing data for known genetic markers associated with AIV adaptation, transmission, and antiviral resistance allows for fast, efficient assessment of AIV risk. Here we summarize and update the current knowledge on experimentally verified molecular markers involved in AIV pathogenicity, receptor binding, replicative capacity, and transmission in both poultry and mammals with a broad focus to include data available on other AIV subtypes outside of A/H5N1 and A/H7N9.
Collapse
Affiliation(s)
- Annika Suttie
- Virology Unit, Institut Pasteur du Cambodge, Institut Pasteur International Network, 5 Monivong Blvd, PO Box #983, Phnom Penh, Cambodia
- School of Health and Life Sciences, Federation University, Churchill, Australia
- World Health Organization Collaborating Centre for Reference and Research on Influenza, Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Yi-Mo Deng
- World Health Organization Collaborating Centre for Reference and Research on Influenza, Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Andrew R Greenhill
- School of Health and Life Sciences, Federation University, Churchill, Australia
| | - Philippe Dussart
- Virology Unit, Institut Pasteur du Cambodge, Institut Pasteur International Network, 5 Monivong Blvd, PO Box #983, Phnom Penh, Cambodia
| | - Paul F Horwood
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
| | - Erik A Karlsson
- Virology Unit, Institut Pasteur du Cambodge, Institut Pasteur International Network, 5 Monivong Blvd, PO Box #983, Phnom Penh, Cambodia.
| |
Collapse
|
18
|
Baker SF, Ledwith MP, Mehle A. Differential Splicing of ANP32A in Birds Alters Its Ability to Stimulate RNA Synthesis by Restricted Influenza Polymerase. Cell Rep 2019; 24:2581-2588.e4. [PMID: 30184493 DOI: 10.1016/j.celrep.2018.08.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 05/15/2018] [Accepted: 08/06/2018] [Indexed: 12/21/2022] Open
Abstract
Adaptation of viruses to their hosts can result in specialization and a restricted host range. Species-specific polymorphisms in the influenza virus polymerase restrict its host range during transmission from birds to mammals. ANP32A was recently identified as a cellular co-factor affecting polymerase adaption and activity. Avian influenza polymerases require ANP32A containing an insertion resulting from an exon duplication uniquely encoded in birds. Here we find that natural splice variants surrounding this exon create avian ANP32A proteins with distinct effects on polymerase activity. We demonstrate species-independent direct interactions between all ANP32A variants and the PB2 polymerase subunit. This interaction is enhanced in the presence of viral genomic RNA. In contrast, only avian ANP32A restored ribonucleoprotein complex assembly for a restricted polymerase by enhancing RNA synthesis. Our data suggest that ANP32A splicing variation among birds differentially affects viral replication, polymerase adaption, and the potential of avian hosts to be reservoirs.
Collapse
Affiliation(s)
- Steven F Baker
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Mitchell P Ledwith
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA; Graduate Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, WI, USA
| | - Andrew Mehle
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA.
| |
Collapse
|
19
|
Gao W, Zu Z, Liu J, Song J, Wang X, Wang C, Liu L, Tong Q, Wang M, Sun H, Sun Y, Liu J, Chang KC, Pu J. Prevailing I292V PB2 mutation in avian influenza H9N2 virus increases viral polymerase function and attenuates IFN-β induction in human cells. J Gen Virol 2019; 100:1273-1281. [PMID: 31305236 PMCID: PMC7414430 DOI: 10.1099/jgv.0.001294] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Adaptation of PB2 protein is important for the establishment of avian influenza viruses in mammalian hosts. Here, we identify I292V as the prevalent mutation in PB2 of circulating avian H9N2 and pandemic H1N1 viruses. The same dominant PB2 mutation is also found in most human isolates of emergent avian H7N9 and H10N8 viruses. In human cells, PB2-292V in H9N2 virus has the combined ability of conferring higher viral polymerase activity and stronger attenuation of IFN-β induction than that of its predecessor PB2-292I. IFN-β attenuation is accompanied by higher binding affinity of PB2-292V for host mitochondrial antiviral signalling protein, an important intermediary protein in the induction of IFN-β. In the mouse in vivo model, PB2-292V mutation increases H9N2 virus replication with ensuing increase in disease severity. Collectively, PB2-292V is a new mammalian adaptive marker that promotes H9N2 virus replication in mammalian hosts with the potential to improve transmission from birds to humans.
Collapse
Affiliation(s)
- Weihua Gao
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Zhipeng Zu
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Jiyu Liu
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Jingwei Song
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Xinyu Wang
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Chenxi Wang
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Litao Liu
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Qi Tong
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Mingyang Wang
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Honglei Sun
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Yipeng Sun
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Jinhua Liu
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| | - Kin-Chow Chang
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough, UK
| | - Juan Pu
- Key Laboratory of Animal Epidemiology, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China
| |
Collapse
|
20
|
Liu X, Yang C, Sun X, Lin X, Zhao L, Chen H, Jin M. Evidence for a novel mechanism of influenza A virus host adaptation modulated by PB2-627. FEBS J 2019; 286:3389-3400. [PMID: 31034753 DOI: 10.1111/febs.14867] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 01/29/2019] [Accepted: 04/26/2019] [Indexed: 12/21/2022]
Abstract
Influenza virus cross-species transmission is restricted by the host, but viruses overcome this restriction by accumulating mutations which allow them to adapt to a new host. Among the many factors which facilitate virus host adaptation, polymerase basic protein 2 (PB2) 627 plays an important role, although the underlying molecular mechanism has not been fully understood. In a previous study, we found that histone H1.2 (encoded by HIST1H1C) regulates human or avian influenza virus replication in different ways, indicating that it might be involved in virus host adaptation. Herein, we found that HIST1H1C expression, phosphorylation and methylation levels are decreased when infected with H1N1 influenza virus and increased when infected with H5N1 influenza virus. Overexpressing the eight gene segments of the influenza virus, we found that only PB2 significantly affects HIST1H1C expression and modifications. Since the 627 site is different between the H5N1 and H1N1 influenza viruses we constructed PB2-627E (avian variant) and PB2-627K (human variant) mutant viruses, and observed that the effects of the wild-type and the mutant viruses on HIST1H1C expression and modifications are the opposite of one another. Further analysis showed that influenza virus PB2-627 regulates HIST1H1C expression via Sp1, and specifically that PB2-627K down-regulates Sp1 and HIST1H1C while PB2-627E up-regulates Sp1 and HIST1H1C. In addition, HIST1H1C can feedback regulate DNA-dependent protein kinase and euchromatic histone-lysine N-methyltransferase 1/2, leading to altered HIST1H1C phosphorylation and methylation levels, and affecting influenza virus replication accordingly. In summary, this study illustrates the mechanism of PB2-627E/K-mediated regulation of influenza virus host adaptation.
Collapse
Affiliation(s)
- Xiaokun Liu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Cha Yang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Xiaomei Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Xian Lin
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Lianzhong Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Meilin Jin
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Agro-Microbiology Resources Development - Ministry of Agriculture, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Animal Disease Diagnosis and Immunization - Ministry of Agriculture, Huazhong Agricultural University, Wuhan, China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| |
Collapse
|
21
|
Fundamental Contribution and Host Range Determination of ANP32A and ANP32B in Influenza A Virus Polymerase Activity. J Virol 2019; 93:JVI.00174-19. [PMID: 30996088 PMCID: PMC6580979 DOI: 10.1128/jvi.00174-19] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 04/09/2019] [Indexed: 12/14/2022] Open
Abstract
The polymerase of the influenza virus is part of the key machinery necessary for viral replication. However, the avian influenza virus polymerase is restricted in mammalian cells. The cellular protein ANP32A has been recently found to interact with viral polymerase and to influence both polymerase activity and interspecies restriction. We report here that either human ANP32A or ANP32B is indispensable for human influenza A virus RNA replication. The contribution of huANP32B is equal to that of huANP32A, and together they play a fundamental role in the activity of human influenza A virus polymerase, while neither human ANP32A nor ANP32B supports the activity of avian viral polymerase. Interestingly, we found that avian ANP32B was naturally inactive, leaving avian ANP32A alone to support viral replication. Two amino acid mutations at sites 129 to 130 in chicken ANP32B lead to the loss of support of viral replication and weak interaction with the viral polymerase complex, and these amino acids are also crucial in the maintenance of viral polymerase activity in other ANP32 proteins. Our findings strongly support ANP32A and ANP32B as key factors for both virus replication and adaptation.IMPORTANCE The key host factors involved in the influenza A viral polymerase activity and RNA replication remain largely unknown. We provide evidence here that ANP32A and ANP32B from different species are powerful factors in the maintenance of viral polymerase activity. Human ANP32A and ANP32B contribute equally to support human influenza viral RNA replication. However, unlike avian ANP32A, the avian ANP32B is evolutionarily nonfunctional in supporting viral replication because of a mutation at sites 129 and 130. These sites play an important role in ANP32A/ANP32B and viral polymerase interaction and therefore determine viral replication, suggesting a novel interface as a potential target for the development of anti-influenza strategies.
Collapse
|
22
|
AZT acts as an anti-influenza nucleotide triphosphate targeting the catalytic site of A/PR/8/34/H1N1 RNA dependent RNA polymerase. J Comput Aided Mol Des 2019; 33:387-404. [PMID: 30739239 DOI: 10.1007/s10822-019-00189-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/02/2019] [Indexed: 10/27/2022]
Abstract
To develop potent drugs that inhibit the activity of influenza virus RNA dependent RNA polymerase (RdRp), a set of compounds favipiravir, T-705, T-1105 and T-1106, ribavirin, ribavirin triphosphate viramidine, 2FdGTP (2'-deoxy-2'-fluoroguanosine triphosphate) and AZT-TP (3'-Azido-3'-deoxy-thymidine-5'-triphosphate) were docked with a homology model of IAV RdRp from the A/PR/8/34/H1N1 strain. These compounds bind to four pockets A-D of the IAV RdRp with different mechanism of action. In addition, AZT-TP also binds to the PB1 catalytic site near to the tip of the priming loop with a highest ΔG of - 16.7 Kcal/mol exhibiting an IC50 of 1.12 µM in an in vitro enzyme transcription assay. This shows that AZT-TP mainly prevents the incorporation of incoming nucleotide involved in initiation of vRNA replication. Conversely, 2FdGTP used as a positive control binds to pocket-B at the end of tunnel-II with a highest ΔG of - 16.3 Kcal/mol inhibiting chain termination with a similar IC50 of 1.12 µM. Overall, our computational results in correlation with experimental studies gives information for the first time about the binding modes of the known influenza antiviral compounds in different models of vRNA replication by IAV RdRp. This in turn gives new structural insights for the development of new therapeutics exhibiting high specificity to the PB1 catalytic site of influenza A viruses.
Collapse
|
23
|
Qin J, Peng O, Shen X, Gong L, Xue C, Cao Y. Multiple amino acid substitutions involved in the adaption of three avian-origin H7N9 influenza viruses in mice. Virol J 2019; 16:3. [PMID: 30621708 PMCID: PMC6323857 DOI: 10.1186/s12985-018-1109-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/17/2018] [Indexed: 12/16/2022] Open
Abstract
Background Avian influenza A H7N9 virus has caused five outbreak waves of human infections in China since 2013 and posed a dual challenge to public health and poultry industry. The number of reported H7N9 virus human cases confirmed by laboratory has surpassed that of H5N1 virus. However, the mechanism for how H7N9 influenza virus overcomes host range barrier has not been clearly understood. Methods To generate mouse-adapted H7N9 influenza viruses, we passaged three avian-origin H7N9 viruses in mice by lung-to-lung passages independently. Then, the characteristics between the parental and mouse-adapted H7N9 viruses was compared in the following aspects, including virulence in mice, tropism of different tissues, replication in MDCK cells and molecular mutations. Results After ten passages in mice, MLD50 of the H7N9 viruses reduced >750-3,160,000 folds, and virus titers in MDCK cells increased 10-200 folds at 48 hours post-inoculation. Moreover, the mouse-adapted H7N9 viruses showed more expanded tissue tropism and more serious lung pathological lesions in mice. Further analysis of the amino acids changes revealed 10 amino acid substitutions located in PB2 (E627K), PB1 (W215R and D638G), PA (T97I), HA (H3 numbering: R220G, L226S, G279R and G493R) and NA (P3Q and R134I) proteins. Moreover, PB2 E627K substitution was shared by the three mouse-adapted viruses (two viruses belong to YRD lineage and one virus belongs to PRD lineage), and PA T97A substitution was shared by two mouse-adapted viruses (belong to YRD lineage). Conclusions Our result indicated that the virulence in mice and virus titer in MDCK cells of H7N9 viruses significantly increased after adapted in mouse model. PB2 E627K and PA T97A substitutions are vital in mouse adaption and should be monitored during epidemiological study of H7N9 virus. Electronic supplementary material The online version of this article (10.1186/s12985-018-1109-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Jianru Qin
- State Key Laboratory of Biocontrol, School of Life Sciences, Higher Education Mega Center, Sun Yat-sen University, Guangzhou, 510006, China
| | - Ouyang Peng
- State Key Laboratory of Biocontrol, School of Life Sciences, Higher Education Mega Center, Sun Yat-sen University, Guangzhou, 510006, China
| | - Xiaoting Shen
- State Key Laboratory of Biocontrol, School of Life Sciences, Higher Education Mega Center, Sun Yat-sen University, Guangzhou, 510006, China
| | - Lang Gong
- State Key Laboratory of Biocontrol, School of Life Sciences, Higher Education Mega Center, Sun Yat-sen University, Guangzhou, 510006, China
| | - Chunyi Xue
- State Key Laboratory of Biocontrol, School of Life Sciences, Higher Education Mega Center, Sun Yat-sen University, Guangzhou, 510006, China.
| | - Yongchang Cao
- State Key Laboratory of Biocontrol, School of Life Sciences, Higher Education Mega Center, Sun Yat-sen University, Guangzhou, 510006, China.
| |
Collapse
|
24
|
Martínez-Sobrido L, Peersen O, Nogales A. Temperature Sensitive Mutations in Influenza A Viral Ribonucleoprotein Complex Responsible for the Attenuation of the Live Attenuated Influenza Vaccine. Viruses 2018; 10:E560. [PMID: 30326610 PMCID: PMC6213772 DOI: 10.3390/v10100560] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/03/2018] [Accepted: 10/12/2018] [Indexed: 01/29/2023] Open
Abstract
Live attenuated influenza vaccines (LAIV) have prevented morbidity and mortality associated with influenza viral infections for many years and represent the best therapeutic option to protect against influenza viral infections in humans. However, the development of LAIV has traditionally relied on empirical methods, such as the adaptation of viruses to replicate at low temperatures. These approaches require an extensive investment of time and resources before identifying potential vaccine candidates that can be safely implemented as LAIV to protect humans. In addition, the mechanism of attenuation of these vaccines is poorly understood in some cases. Importantly, LAIV are more efficacious than inactivated vaccines because their ability to mount efficient innate and adaptive humoral and cellular immune responses. Therefore, the design of potential LAIV based on known properties of viral proteins appears to be a highly appropriate option for the treatment of influenza viral infections. For that, the viral RNA synthesis machinery has been a research focus to identify key amino acid substitutions that can lead to viral attenuation and their use in safe, immunogenic, and protective LAIV. In this review, we discuss the potential to manipulate the influenza viral RNA-dependent RNA polymerase (RdRp) complex to generate attenuated forms of the virus that can be used as LAIV for the treatment of influenza viral infections, one of the current and most effective prophylactic options for the control of influenza in humans.
Collapse
Affiliation(s)
- Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, New York, NY 14642, USA.
| | - Olve Peersen
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, CO 80523, USA.
| | - Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, New York, NY 14642, USA.
| |
Collapse
|
25
|
Gun L, Haixian P, Yumiao R, Han T, Jingqi L, Liguang Z. Codon usage characteristics of PB2 gene in influenza A H7N9 virus from different host species. INFECTION GENETICS AND EVOLUTION 2018; 65:430-435. [PMID: 30179716 DOI: 10.1016/j.meegid.2018.08.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 08/02/2018] [Accepted: 08/30/2018] [Indexed: 12/13/2022]
Abstract
The influenza A H7N9 virus is a highly contagious virus which can only infect poultry before early 2013. But after that time, it widely caused human infections in China and brought Southeast Asia great threaten in the public health area. The coding gene for polymerase basic protein 2 (PB2) in influenza A H7N9 virus encodes the PB2 protein, which is a part of the RNA polymerase. The enzyme lacks a correction function during its own replication process, so the mutation frequency of the influenza A H7N9 virus gene is high and the PB2 gene is also included. To investigate the codon usages characteristics of PB2 gene, gene sequences of 12 kinds of poultry are downloaded form the gene bank (NCBI) and their codon usage characteristics such as the effective number of codons (ENC), the evolutionary relationship of the sequences, the codon adaptation index (CAI), the correspondence analysis (COA), the relative synonymous codon usage (RSCU) and their PR2-bias are compared and studied. The value of these reults showed that there is a low codon usage bias in the PB2 gene. Then, the differences between the codon usages of PB2 gene from 12 kinds of poultry are compared and their potential applications are discussed. These results could lay a foundation for other further study on the evolution of H7N9.
Collapse
Affiliation(s)
- Li Gun
- Department of Biomedical Engineering, School of Electronics and Information Engineering, Xi'an Technological University, Xi'an, Shaanxi Province, China.
| | - Pan Haixian
- Department of Biomedical Engineering, School of Electronics and Information Engineering, Xi'an Technological University, Xi'an, Shaanxi Province, China
| | - Ren Yumiao
- Department of Biomedical Engineering, School of Electronics and Information Engineering, Xi'an Technological University, Xi'an, Shaanxi Province, China
| | - Tian Han
- Department of Biomedical Engineering, School of Electronics and Information Engineering, Xi'an Technological University, Xi'an, Shaanxi Province, China
| | - Lu Jingqi
- Department of Biomedical Engineering, School of Electronics and Information Engineering, Xi'an Technological University, Xi'an, Shaanxi Province, China
| | - Zhang Liguang
- Department of Biomedical Engineering, School of Electronics and Information Engineering, Xi'an Technological University, Xi'an, Shaanxi Province, China
| |
Collapse
|
26
|
The Surface-Exposed PA 51-72-Loop of the Influenza A Virus Polymerase Is Required for Viral Genome Replication. J Virol 2018; 92:JVI.00687-18. [PMID: 29875249 PMCID: PMC6069170 DOI: 10.1128/jvi.00687-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 05/29/2018] [Indexed: 12/30/2022] Open
Abstract
Influenza A viruses are a major global health threat, not only causing significant morbidity and mortality every year but also having the potential to cause severe pandemic outbreaks like the 1918 influenza pandemic. The viral polymerase is a protein complex which is responsible for transcription and replication of the viral genome and therefore is an attractive target for antiviral drug development. For that purpose it is important to understand the mechanisms of how the virus replicates its genome and how the viral polymerase works on a molecular level. In this report, we characterize the role of the flexible surface-exposed PA51-72-loop in polymerase function and offer new insights into the replication mechanism of influenza A viruses. The heterotrimeric influenza A virus RNA-dependent RNA polymerase complex, composed of PB1, PB2, and PA subunits, is responsible for transcribing and replicating the viral RNA genome. The N-terminal endonuclease domain of the PA subunit performs endonucleolytic cleavage of capped host RNAs to generate capped RNA primers for viral transcription. A surface-exposed flexible loop (PA51-72-loop) in the PA endonuclease domain has been shown to be dispensable for endonuclease activity. Interestingly, the PA51-72-loop was found to form different intramolecular interactions depending on the conformational arrangement of the polymerase. In this study, we show that a PA subunit lacking the PA51-72-loop assembles into a heterotrimeric polymerase with PB1 and PB2. We demonstrate that in a cellular context, the PA51-72-loop is required for RNA replication but not transcription by the viral polymerase. In agreement, recombinant viral polymerase lacking the PA51-72-loop is able to carry out cap-dependent transcription but is inhibited in de novo replication initiation in vitro. Furthermore, viral RNA (vRNA) synthesis is also restricted during ApG-primed extension, indicating that the PA51-72-loop is required not only for replication initiation but also for elongation on a cRNA template. We propose that the PA51-72-loop plays a role in the stabilization of the replicase conformation of the polymerase. Together, these results further our understanding of influenza virus RNA genome replication in general and highlight a role of the PA endonuclease domain in polymerase function in particular. IMPORTANCE Influenza A viruses are a major global health threat, not only causing significant morbidity and mortality every year but also having the potential to cause severe pandemic outbreaks like the 1918 influenza pandemic. The viral polymerase is a protein complex which is responsible for transcription and replication of the viral genome and therefore is an attractive target for antiviral drug development. For that purpose it is important to understand the mechanisms of how the virus replicates its genome and how the viral polymerase works on a molecular level. In this report, we characterize the role of the flexible surface-exposed PA51-72-loop in polymerase function and offer new insights into the replication mechanism of influenza A viruses.
Collapse
|
27
|
Serna Martin I, Hengrung N, Renner M, Sharps J, Martínez-Alonso M, Masiulis S, Grimes JM, Fodor E. A Mechanism for the Activation of the Influenza Virus Transcriptase. Mol Cell 2018; 70:1101-1110.e4. [PMID: 29910112 PMCID: PMC6024077 DOI: 10.1016/j.molcel.2018.05.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/17/2018] [Accepted: 05/08/2018] [Indexed: 12/28/2022]
Abstract
Influenza virus RNA polymerase (FluPol), a heterotrimer composed of PB1, PB2, and PA subunits (P3 in influenza C), performs both transcription and replication of the viral RNA genome. For transcription, FluPol interacts with the C-terminal domain (CTD) of RNA polymerase II (Pol II), which enables FluPol to snatch capped RNA primers from nascent host RNAs. Here, we describe the co-crystal structure of influenza C virus polymerase (FluPolC) bound to a Ser5-phosphorylated CTD (pS5-CTD) peptide. The position of the CTD-binding site at the interface of PB1, P3, and the flexible PB2 C-terminal domains suggests that CTD binding stabilizes the transcription-competent conformation of FluPol. In agreement, both cap snatching and capped primer-dependent transcription initiation by FluPolC are enhanced in the presence of pS5-CTD. Mutations of amino acids in the CTD-binding site reduce viral mRNA synthesis. We propose a model for the activation of the influenza virus transcriptase through its association with pS5-CTD of Pol II.
Collapse
Affiliation(s)
- Itziar Serna Martin
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Narin Hengrung
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK; Division of Structural Biology, Henry Wellcome Building for Genomic Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - Max Renner
- Division of Structural Biology, Henry Wellcome Building for Genomic Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - Jane Sharps
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Mónica Martínez-Alonso
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Simonas Masiulis
- Division of Structural Biology, Henry Wellcome Building for Genomic Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - Jonathan M Grimes
- Division of Structural Biology, Henry Wellcome Building for Genomic Medicine, University of Oxford, Oxford OX3 7BN, UK; Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK.
| | - Ervin Fodor
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
| |
Collapse
|
28
|
Wen L, Chu H, Wong BHY, Wang D, Li C, Zhao X, Chiu MC, Yuan S, Fan Y, Chen H, Zhou J, Yuen KY. Large-scale sequence analysis reveals novel human-adaptive markers in PB2 segment of seasonal influenza A viruses. Emerg Microbes Infect 2018; 7:47. [PMID: 29593225 PMCID: PMC5874250 DOI: 10.1038/s41426-018-0050-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/09/2018] [Accepted: 02/18/2018] [Indexed: 12/12/2022]
Abstract
To elucidate the adaptive strategies of influenza A viruses (IAVs) to human, we proposed a computational approach to identify human-adaptive mutations in seasonal IAVs, which have not been analyzed comprehensively. We compared representative PB2 sequences of 1425 avian IAVs and 2176 human IAVs and identified a total of 42 human-adaptive markers, including 28 and 31 markers in PB2 proteins of seasonal viruses H1N1 and H3N2, respectively. Notably, this comprehensive list encompasses almost all the markers identified in prior computational studies and 21 novel markers including an experimentally verified mutation K526R, suggesting the predictive power of our method. The strength of our analysis derives from the enormous amount of recently available sequences as well as the recognition that human-adaptive mutations are not necessarily conserved across subtypes. We also utilized mutual information to profile the inter-residue coevolution in PB2 protein. A total of 35 and 46 coevolving site pairs are identified in H1N1 and H3N2, respectively. Interestingly, 13 out of the 28 (46.4%) identified markers in H1N1 and 16 out of the 31 (51.6%) in H3N2 are embraced in the coevolving pairs. Many of them are paired with well-characterized human-adaptive mutations, indicating potential epistatic effect of these coevolving residues in human adaptation. Additionally, we reconstructed the PB2 evolutionary history of seasonal IAVs and demonstrated the distinct adaptive pathway of PB2 segment after reassortment from H1 to H3 lineage. Our study may provide clues for further experimental validation of human-adaptive mutations and shed light on the human adaptation process of seasonal IAVs.
Collapse
Affiliation(s)
- Lei Wen
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Hin Chu
- Department of Microbiology, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China
| | - Bosco Ho-Yin Wong
- State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China
| | - Dong Wang
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Cun Li
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Xiaoyu Zhao
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Man-Chun Chiu
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Shuofeng Yuan
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Yanhui Fan
- Department of Biochemistry, The University of Hong Kong, Hong Kong, China
| | - Honglin Chen
- Department of Microbiology, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong, China
| | - Jie Zhou
- Department of Microbiology, The University of Hong Kong, Hong Kong, China. .,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China. .,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China.
| | - Kwok-Yung Yuen
- Department of Microbiology, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong, China
| |
Collapse
|
29
|
Oymans J, Te Velthuis AJW. A Mechanism for Priming and Realignment during Influenza A Virus Replication. J Virol 2018; 92:e01773-17. [PMID: 29118119 PMCID: PMC5774886 DOI: 10.1128/jvi.01773-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 10/31/2017] [Indexed: 11/20/2022] Open
Abstract
The influenza A virus genome consists of eight segments of single-stranded RNA. These segments are replicated and transcribed by a viral RNA-dependent RNA polymerase (RdRp) that is made up of the influenza virus proteins PB1, PB2, and PA. To copy the viral RNA (vRNA) genome segments and the cRNA segments, the replicative intermediate of viral replication, the RdRp must use two promoters and two different de novo initiation mechanisms. On the vRNA promoter, the RdRp initiates on the 3' terminus, while on the cRNA promoter, the RdRp initiates internally and subsequently realigns the nascent vRNA product to ensure that the template is copied in full. In particular, the latter process, which is also used by other RNA viruses, is not understood. Here we provide mechanistic insight into priming and realignment during influenza virus replication and show that it is controlled by the priming loop and a helix-loop-helix motif of the PB1 subunit of the RdRp. Overall, these observations advance our understanding of how the influenza A virus initiates viral replication and amplifies the genome correctly.IMPORTANCE Influenza A viruses cause severe disease in humans and are considered a major threat to our economy and health. The viruses replicate and transcribe their genome by using an enzyme called the RNA polymerases. To ensure that the genome is amplified faithfully and that abundant viral mRNAs are made for viral protein synthesis, the RNA polymerase must work correctly. In this report, we provide insight into the mechanism that the RNA polymerase employs to ensure that the viral genome is copied correctly.
Collapse
Affiliation(s)
- Judith Oymans
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Aartjan J W Te Velthuis
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- University of Cambridge, Department of Pathology, Division of Virology, Addenbrooke's Hospital, Cambridge, United Kingdom
| |
Collapse
|
30
|
Hsia HP, Yang YH, Szeto WC, Nilsson BE, Lo CY, Ng AKL, Fodor E, Shaw PC. Amino acid substitutions affecting aspartic acid 605 and valine 606 decrease the interaction strength between the influenza virus RNA polymerase PB2 '627' domain and the viral nucleoprotein. PLoS One 2018; 13:e0191226. [PMID: 29338047 PMCID: PMC5770049 DOI: 10.1371/journal.pone.0191226] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 12/29/2017] [Indexed: 11/19/2022] Open
Abstract
The influenza virus RNA genome is transcribed and replicated in the context of the viral ribonucleoprotein (vRNP) complex by the viral RNA polymerase. The nucleoprotein (NP) is the structural component of the vRNP providing a scaffold for the viral RNA. In the vRNP as well as during transcription and replication the viral polymerase interacts with NP but it is unclear which parts of the polymerase and NP mediate these interactions. Previously the C-terminal ‘627’ domain (amino acids 538–693) of PB2 was shown to interact with NP. Here we report that a fragment encompassing amino acids 146–185 of NP is sufficient to mediate this interaction. Using NMR chemical shift perturbation assays we show that amino acid region 601 to 607 of the PB2 ‘627’ domain interacts with this fragment of NP. Substitutions of these PB2 amino acids resulted in diminished RNP activity and surface plasmon resonance assays showed that amino acids D605 was essential for the interaction with NP and V606 may also play a partial role in the interaction. Collectively these results reveal a possible interaction surface between NP and the PB2 subunit of the RNA polymerase complex.
Collapse
Affiliation(s)
- Ho-Pan Hsia
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Yin-Hua Yang
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Wun-Chung Szeto
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Benjamin E. Nilsson
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Chun-Yeung Lo
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Andy Ka-Leung Ng
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Ervin Fodor
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Pang-Chui Shaw
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
- * E-mail:
| |
Collapse
|
31
|
Jordan PC, Stevens SK, Deval J. Nucleosides for the treatment of respiratory RNA virus infections. Antivir Chem Chemother 2018; 26:2040206618764483. [PMID: 29562753 PMCID: PMC5890544 DOI: 10.1177/2040206618764483] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 02/07/2018] [Indexed: 12/20/2022] Open
Abstract
Influenza virus, respiratory syncytial virus, human metapneumovirus, parainfluenza virus, coronaviruses, and rhinoviruses are among the most common viruses causing mild seasonal colds. These RNA viruses can also cause lower respiratory tract infections leading to bronchiolitis and pneumonia. Young children, the elderly, and patients with compromised cardiac, pulmonary, or immune systems are at greatest risk for serious disease associated with these RNA virus respiratory infections. In addition, swine and avian influenza viruses, together with severe acute respiratory syndrome-associated and Middle Eastern respiratory syndrome coronaviruses, represent significant pandemic threats to the general population. In this review, we describe the current medical need resulting from respiratory infections caused by RNA viruses, which justifies drug discovery efforts to identify new therapeutic agents. The RNA polymerase of respiratory viruses represents an attractive target for nucleoside and nucleotide analogs acting as inhibitors of RNA chain synthesis. Here, we present the molecular, biochemical, and structural fundamentals of the polymerase of the four major families of RNA respiratory viruses: Orthomyxoviridae, Pneumoviridae/Paramyxoviridae, Coronaviridae, and Picornaviridae. We summarize past and current efforts to develop nucleoside and nucleotide analogs as antiviral agents against respiratory virus infections. This includes molecules with very broad antiviral spectrum such as ribavirin and T-705 (favipiravir), and others targeting more specifically one or a few virus families. Recent advances in our understanding of the structure(s) and function(s) of respiratory virus polymerases will likely support the discovery and development of novel nucleoside analogs.
Collapse
Affiliation(s)
- Paul C Jordan
- Alios BioPharma, Inc., a Janssen Pharmaceutical Company of Johnson & Johnson, South San Francisco, USA
| | - Sarah K Stevens
- Alios BioPharma, Inc., a Janssen Pharmaceutical Company of Johnson & Johnson, South San Francisco, USA
| | - Jerome Deval
- Alios BioPharma, Inc., a Janssen Pharmaceutical Company of Johnson & Johnson, South San Francisco, USA
| |
Collapse
|
32
|
Abstract
Influenza is a negative-sense single-stranded RNA virus with segmented genome. Each segment is encapsidated by a ribonucleoprotein (RNP) complex composed of RNA-dependent RNA polymerase (RdRP) and multiple copies of nucleoprotein (NP). The RNP complex plays a crucial role in viral life cycle, supporting and regulating transcription and replication of viral genome in infected cells. The structural characterization of RdRP and RNP in recent years has shed light on its functions and mechanism of action. In this review, we summarize current understanding on the structure of RNP complex, as well as the structure of each subunit. Crucial functions of RNP are also discussed.
Collapse
Affiliation(s)
- Chun-Yeung Lo
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong, China
| | - Yun-Sang Tang
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong, China
| | - Pang-Chui Shaw
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong, China.
| |
Collapse
|