1
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Grosse S, Cooymans L, Embrechts W, McGowan D, Jacoby E, Stoops B, Gupta K, Ackermann M, Alnajjar S, Guillemont J, Jin Z, Kesteleyn B, Matcha K, Sriboonyapirat P, Truong A, Van Den Berg J, Yu X, Herschke F, Roymans D, Raboisson P, Rigaux P, Jonckers THM. Discovery of gem-Dimethyl-hydroxymethylpyridine Derivatives as Potent Non-nucleoside RSV Polymerase Inhibitors. J Med Chem 2024. [PMID: 39105710 DOI: 10.1021/acs.jmedchem.4c00525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/07/2024]
Abstract
Respiratory syncytial virus (RSV) is an RNA virus infecting the upper and lower respiratory tract and is recognized as a major respiratory health threat, particularly to older adults, immunocompromised individuals, and young children. Around 64 million children and adults are infected every year worldwide. Despite two vaccines and a new generation monoclonal antibody recently approved, no effective antiviral treatment is available. In this manuscript, we present the medicinal chemistry efforts resulting in the identification of compound 28 (JNJ-8003), a novel RSV non-nucleoside inhibitor displaying subnanomolar activity in vitro as well as prominent efficacy in mice and a neonatal lamb models.
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Affiliation(s)
- Sandrine Grosse
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Ludwig Cooymans
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Werner Embrechts
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | | | - Edgar Jacoby
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Bart Stoops
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Kusum Gupta
- Neuron23 Inc. 343 Oyster Point Blvd, South San Francisco, California 94080, United States
| | | | - Sarhad Alnajjar
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7AL, U.K
| | | | - Zhinan Jin
- Janssen Pharmaceutica NV, Brisbane, California 94005, United States
| | - Bart Kesteleyn
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Kiran Matcha
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | | | - Anh Truong
- Neuron23 Inc. 343 Oyster Point Blvd, South San Francisco, California 94080, United States
| | - Joke Van Den Berg
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Xiaodi Yu
- Janssen Pharmaceutica NV, Spring House, Pennsylvania 19477 United States
| | - Florence Herschke
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Dirk Roymans
- DNS Life Sciences Consulting, Brandhoefstraat 63, 2300 Turnhout, Belgium
| | - Pierre Raboisson
- Galapagos, General De Wittelaan L112, A3, 2800 Mechelen, Belgium
| | - Peter Rigaux
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Tim H M Jonckers
- Janssen Research & Development, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
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2
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Kleiner VA, Fearns R. How does the polymerase of non-segmented negative strand RNA viruses commit to transcription or genome replication? J Virol 2024:e0033224. [PMID: 39078194 DOI: 10.1128/jvi.00332-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2024] Open
Abstract
The Mononegavirales, or non-segmented negative-sense RNA viruses (nsNSVs), includes significant human pathogens, such as respiratory syncytial virus, parainfluenza virus, measles virus, Ebola virus, and rabies virus. Although these viruses differ widely in their pathogenic properties, they are united by each having a genome consisting of a single strand of negative-sense RNA. Consistent with their shared genome structure, the nsNSVs have evolved similar ways to transcribe their genome into mRNAs and replicate it to produce new genomes. Importantly, both mRNA transcription and genome replication are performed by a single virus-encoded polymerase. A fundamental and intriguing question is: how does the nsNSV polymerase commit to being either an mRNA transcriptase or a replicase? The polymerase must become committed to one process or the other either before it interacts with the genome template or in its initial interactions with the promoter sequence at the 3´ end of the genomic RNA. This review examines the biochemical, molecular biology, and structural biology data regarding the first steps of transcription and RNA replication that have been gathered over several decades for different families of nsNSVs. These findings are discussed in relation to possible models that could explain how an nsNSV polymerase initiates and commits to either transcription or genome replication.
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Affiliation(s)
- Victoria A Kleiner
- Department of Virology, Immunology & Microbiology, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Rachel Fearns
- Department of Virology, Immunology & Microbiology, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
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3
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Musa AO, Faber SR, Forrest K, Smith KP, Sengupta S, López CB. Identification of distinct genotypes in circulating RSV A strains based on variants in the virus replication-associated genes. J Virol 2024:e0099024. [PMID: 39007617 DOI: 10.1128/jvi.00990-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Accepted: 06/16/2024] [Indexed: 07/16/2024] Open
Abstract
Respiratory syncytial virus (RSV) is a common cause of respiratory infection that often leads to hospitalization of infected younger children and older adults. RSV is classified into two strains, A and B, each with several subgroups or genotypes. One issue with the definition of these subgroups is the lack of a unified method of identification or genotyping. We propose that genotyping strategies based on the genes coding for replication-associated proteins could provide critical information on the replication capacity of the distinct subgroups, while clearly distinguishing genotypes. Here, we analyzed the virus replication-associated genes N, P, M2, and L from de novo assembled RSV A sequences obtained from 31 newly sequenced samples from hospitalized patients in Philadelphia and 78 additional publicly available sequences from different geographic locations within the United States. In-depth analysis and annotation of variants in the replication-associated proteins identified the polymerase protein L as a robust target for genotyping RSV subgroups. Importantly, our analysis revealed non-synonymous variations in L that were consistently accompanied by conserved changes in its co-factor P or the M2-2 protein, suggesting associations and interactions between specific domains of these proteins. Similar associations were seen among sequences of the related human metapneumovirus. These results highlight L as an alternative to other RSV genotyping targets and demonstrate the value of in-depth analyses and annotations of RSV sequences as it can serve as a foundation for subsequent in vitro and clinical studies on the efficiency of the polymerase and fitness of different virus isolates.IMPORTANCEGiven the historical heterogeneity of respiratory syncytial virus (RSV) and the disease it causes, there is a need to understand the properties of the circulating RSV strains each season. This information would benefit from an informative and consensus method of genotyping the virus. Here, we carried out a variant analysis that shows a pattern of specific variations among the replication-associated genes of RSV A across different seasons. Interestingly, these variation patterns, which were also seen in human metapneumovirus sequences, point to previously defined interactions of domains within these genes, suggesting co-variation in the replication-associated genes. Our results also suggest a genotyping strategy that can prove to be particularly important in understanding the genotype-phenotype correlation in the era of RSV vaccination, where selective pressure on the virus to evolve is anticipated. More importantly, the categorization of pneumoviruses based on these patterns may be of prognostic value.
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Affiliation(s)
- Abdulafiz O Musa
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Center for Women's Infectious Diseases Research, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Sydney R Faber
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Center for Women's Infectious Diseases Research, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Kaitlyn Forrest
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Kenneth P Smith
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Infectious Disease Diagnostics Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Shaon Sengupta
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Carolina B López
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Center for Women's Infectious Diseases Research, Washington University School of Medicine, Saint Louis, Missouri, USA
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4
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Oraby A, Bilawchuk L, West FG, Marchant DJ. Structure-Based Discovery of Allosteric Inhibitors Targeting a New Druggable Site in the Respiratory Syncytial Virus Polymerase. ACS OMEGA 2024; 9:22213-22229. [PMID: 38799318 PMCID: PMC11112712 DOI: 10.1021/acsomega.4c01207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/08/2024] [Accepted: 04/12/2024] [Indexed: 05/29/2024]
Abstract
Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory infections for which effective treatment options remain limited. Herein, we employed a computational structure-based design strategy aimed at identifying potential targets for a new class of allosteric inhibitors. Our investigation led to the discovery of a previously undisclosed allosteric binding site within the RSV polymerase, the large (L) protein. This discovery was achieved through a combination of virtual screening and molecular dynamics simulations. Subsequently, we identified two inhibitors, 6a and 10b, which both exhibited promising antiviral activity in the low micromolar range. Resistance profiling revealed a distinctive pattern in how RSV evaded treatment with this class of inhibitors. This pattern strongly suggested that this class of small molecules was targeting a new binding site in the RSV L protein, aligning with the computational predictions made in our study. This study paves the way for the development of more potent inhibitors for combating RSV infections by targeting a new druggable pocket within the RdRp which does not overlap with previously known resistance sites.
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Affiliation(s)
- Ahmed
K. Oraby
- Department
of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2R3, Canada
- Department
of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
- Department
of Pharmaceutical Organic Chemistry, College of Pharmaceutical Sciences
and Drug Manufacturing, Misr University
for Science and Technology, 6th
of October City P.O. Box 77,Egypt
| | - Leanne Bilawchuk
- Department
of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Frederick G. West
- Department
of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - David J. Marchant
- Department
of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2R3, Canada
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5
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Palazzotti D, Sguilla M, Manfroni G, Cecchetti V, Astolfi A, Barreca ML. Small Molecule Drugs Targeting Viral Polymerases. Pharmaceuticals (Basel) 2024; 17:661. [PMID: 38794231 PMCID: PMC11124969 DOI: 10.3390/ph17050661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
Small molecules that specifically target viral polymerases-crucial enzymes governing viral genome transcription and replication-play a pivotal role in combating viral infections. Presently, approved polymerase inhibitors cover nine human viruses, spanning both DNA and RNA viruses. This review provides a comprehensive analysis of these licensed drugs, encompassing nucleoside/nucleotide inhibitors (NIs), non-nucleoside inhibitors (NNIs), and mutagenic agents. For each compound, we describe the specific targeted virus and related polymerase enzyme, the mechanism of action, and the relevant bioactivity data. This wealth of information serves as a valuable resource for researchers actively engaged in antiviral drug discovery efforts, offering a complete overview of established strategies as well as insights for shaping the development of next-generation antiviral therapeutics.
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Affiliation(s)
| | | | | | | | | | - Maria Letizia Barreca
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy; (D.P.); (M.S.); (G.M.); (V.C.); (A.A.)
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6
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Li T, Liu M, Gu Z, Su X, Liu Y, Lin J, Zhang Y, Shen QT. Structures of the mumps virus polymerase complex via cryo-electron microscopy. Nat Commun 2024; 15:4189. [PMID: 38760379 PMCID: PMC11101452 DOI: 10.1038/s41467-024-48389-9] [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: 06/24/2023] [Accepted: 04/26/2024] [Indexed: 05/19/2024] Open
Abstract
The viral polymerase complex, comprising the large protein (L) and phosphoprotein (P), is crucial for both genome replication and transcription in non-segmented negative-strand RNA viruses (nsNSVs), while structures corresponding to these activities remain obscure. Here, we resolved two L-P complex conformations from the mumps virus (MuV), a typical member of nsNSVs, via cryogenic-electron microscopy. One conformation presents all five domains of L forming a continuous RNA tunnel to the methyltransferase domain (MTase), preferably as a transcription state. The other conformation has the appendage averaged out, which is inaccessible to MTase. In both conformations, parallel P tetramers are revealed around MuV L, which, together with structures of other nsNSVs, demonstrates the diverse origins of the L-binding X domain of P. Our study links varying structures of nsNSV polymerase complexes with genome replication and transcription and points to a sliding model for polymerase complexes to advance along the RNA templates.
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Affiliation(s)
- Tianhao Li
- School of Life Sciences, Department of Chemical Biology, Southern University of Science and Technology, Shenzhen, 518055, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Mingdong Liu
- School of Life Sciences, Department of Chemical Biology, Southern University of Science and Technology, Shenzhen, 518055, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Zhanxi Gu
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Key Laboratory of Synthetic Biology, Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Xin Su
- School of Life Sciences, Department of Chemical Biology, Southern University of Science and Technology, Shenzhen, 518055, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, 200438, China
| | - Yunhui Liu
- School of Life Sciences, Department of Chemical Biology, Southern University of Science and Technology, Shenzhen, 518055, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Jinzhong Lin
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, 200438, China
| | - Yu Zhang
- Key Laboratory of Synthetic Biology, Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Qing-Tao Shen
- School of Life Sciences, Department of Chemical Biology, Southern University of Science and Technology, Shenzhen, 518055, China.
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China.
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
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7
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Musa AO, Faber SR, Forrest K, Smith KP, Sengupta S, López CB. Identification of distinct genotypes in circulating RSV A strains based on variants on the virus replication-associated genes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590570. [PMID: 38712045 PMCID: PMC11071361 DOI: 10.1101/2024.04.22.590570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Respiratory syncytial virus is a common cause of respiratory infection that often leads to hospitalization of infected younger children and older adults. RSV is classified into two strains, A and B, each with several subgroups or genotypes. One issue with the definition of these subgroups is the lack of a unified method of identification or genotyping. We propose that genotyping strategies based on the genes coding for replication-associated proteins could provide critical information on the replication capacity of the distinct subgroup, while clearly distinguishing genotypes. Here, we analyzed the virus replication-associated genes N, P, M2, and L from de novo assembled RSV A sequences obtained from 31 newly sequenced samples from hospitalized patients in Philadelphia and 78 additional publicly available sequences from different geographic locations within the US. In-depth analysis and annotation of the protein variants in L and the other replication-associated proteins N, P, M2-1, and M2-2 identified the polymerase protein L as a robust target for genotyping RSV subgroups. Importantly, our analysis revealed non-synonymous variations in L that were consistently accompanied by conserved changes in its co-factor P or the M2-2 protein, suggesting associations and interactions between specific domains of these proteins. These results highlight L as an alternative to other RSV genotyping targets and demonstrate the value of in-depth analyses and annotations of RSV sequences as it can serve as a foundation for subsequent in vitro and clinical studies on the efficiency of the polymerase and fitness of different virus isolates.
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Affiliation(s)
- Abdulafiz O. Musa
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Center for Womeńs Infectious Diseases Research, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Sydney R. Faber
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Center for Womeńs Infectious Diseases Research, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Kaitlyn Forrest
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Neonatology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Kenneth P. Smith
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Infectious Disease Diagnostics Laboratory, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Shaon Sengupta
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Neonatology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Carolina B. López
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
- Center for Womeńs Infectious Diseases Research, Washington University School of Medicine, Saint Louis, Missouri, USA
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8
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Jobe F, Kelly JT, Simpson J, Wells J, Armstrong SD, Spick M, Lacey E, Logan L, Geifman N, Hawes P, Bailey D. Viral PIC-pocketing: RSV sequestration of translational preinitiation complexes into bi-phasic biomolecular condensates. J Virol 2024; 98:e0015324. [PMID: 38421168 PMCID: PMC10949503 DOI: 10.1128/jvi.00153-24] [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: 01/22/2024] [Accepted: 01/26/2024] [Indexed: 03/02/2024] Open
Abstract
Orthopneumoviruses characteristically form membrane-less cytoplasmic inclusion bodies (IBs) wherein RNA replication and transcription occur. Here, we report a strategy whereby the orthopneumoviruses sequester various components of the translational preinitiation complex machinery into viral inclusion bodies to facilitate translation of their own mRNAs-PIC-pocketing. Electron microscopy of respiratory syncytial virus (RSV)-infected cells revealed bi-phasic organization of IBs, specifically, spherical "droplets" nested within the larger inclusion. Using correlative light and electron microscopy, combined with fluorescence in situ hybridization, we showed that the observed bi-phasic morphology represents functional compartmentalization of the inclusion body and that these domains are synonymous with the previously reported inclusion body-associated granules (IBAGs). Detailed analysis demonstrated that IBAGs concentrate nascent viral mRNA, the viral M2-1 protein as well as components of eukaryotic translation initiation factors (eIF), eIF4F and eIF3, and 40S complexes involved in translation initiation. Interestingly, although ribopuromycylation-based imaging indicates that the majority of viral mRNA translation occurs in the cytoplasm, there was some evidence for intra-IBAG translation, consistent with the likely presence of ribosomes in a subset of IBAGs imaged by electron microscopy. Mass spectrometry analysis of sub-cellular fractions from RSV-infected cells identified significant modification of the cellular translation machinery; however, interestingly, ribopuromycylation assays showed no changes to global levels of translation. The mechanistic basis for this pathway was subsequently determined to involve the viral M2-1 protein interacting with eIF4G, likely to facilitate its transport between the cytoplasm and the separate phases of the viral inclusion body. In summary, our data show that these viral organelles function to spatially regulate early steps in viral translation within a highly selective bi-phasic biomolecular condensate. IMPORTANCE Respiratory syncytial viruses (RSVs) of cows and humans are a significant cause of morbidity and mortality in their respective populations. These RNA viruses replicate in the infected cells by compartmentalizing the cell's cytoplasm into distinct viral microdomains called inclusion bodies (IBs). In this paper, we show that these IBs are further compartmentalized into smaller structures that have significantly different density, as observed by electron microscopy. Within smaller intra-IB structures, we observed ribosomal components and evidence for active translation. These findings highlight that RSV may additionally compartmentalize translation to favor its own replication in the cell. These data contribute to our understanding of how RNA viruses hijack the cell to favor replication of their own genomes and may provide new targets for antiviral therapeutics in vivo.
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Affiliation(s)
| | | | | | - Joanna Wells
- The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Stuart D. Armstrong
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Matt Spick
- School of Health Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Emily Lacey
- The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Leanne Logan
- The Pirbright Institute, Woking, Surrey, United Kingdom
| | - Nophar Geifman
- School of Health Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | | | - Dalan Bailey
- The Pirbright Institute, Woking, Surrey, United Kingdom
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9
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Zou G, Cao S, Gao Z, Yie J, Wu JZ. Current state and challenges in respiratory syncytial virus drug discovery and development. Antiviral Res 2024; 221:105791. [PMID: 38160942 DOI: 10.1016/j.antiviral.2023.105791] [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: 11/21/2023] [Revised: 12/22/2023] [Accepted: 12/23/2023] [Indexed: 01/03/2024]
Abstract
Human respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infections (LRTI) in young children and elderly people worldwide. Recent significant progress in our understanding of the structure and function of RSV proteins has led to the discovery of several clinical candidates targeting RSV fusion and replication. These include both the development of novel small molecule interventions and the isolation of potent monoclonal antibodies. In this review, we summarize the state-of-the-art of RSV drug discovery, with a focus on the characteristics of the candidates that reached the clinical stage of development. We also discuss the lessons learned from failed and discontinued clinical developments and highlight the challenges that remain for development of RSV therapies.
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Affiliation(s)
- Gang Zou
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China.
| | - Sushan Cao
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
| | - Zhao Gao
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
| | - Junming Yie
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
| | - Jim Zhen Wu
- Shanghai Ark Biopharmaceutical Co., Ltd, Shanghai, 201203, China
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10
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Cao D, Gao Y, Chen Z, Gooneratne I, Roesler C, Mera C, D'Cunha P, Antonova A, Katta D, Romanelli S, Wang Q, Rice S, Lemons W, Ramanathan A, Liang B. Structures of the promoter-bound respiratory syncytial virus polymerase. Nature 2024; 625:611-617. [PMID: 38123676 PMCID: PMC10794133 DOI: 10.1038/s41586-023-06867-y] [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: 04/30/2023] [Accepted: 11/14/2023] [Indexed: 12/23/2023]
Abstract
The respiratory syncytial virus (RSV) polymerase is a multifunctional RNA-dependent RNA polymerase composed of the large (L) protein and the phosphoprotein (P). It transcribes the RNA genome into ten viral mRNAs and replicates full-length viral genomic and antigenomic RNAs1. The RSV polymerase initiates RNA synthesis by binding to the conserved 3'-terminal RNA promoters of the genome or antigenome2. However, the lack of a structure of the RSV polymerase bound to the RNA promoter has impeded the mechanistic understanding of RSV RNA synthesis. Here we report cryogenic electron microscopy structures of the RSV polymerase bound to its genomic and antigenomic viral RNA promoters, representing two of the first structures of an RNA-dependent RNA polymerase in complex with its RNA promoters in non-segmented negative-sense RNA viruses. The overall structures of the promoter-bound RSV polymerases are similar to that of the unbound (apo) polymerase. Our structures illustrate the interactions between the RSV polymerase and the RNA promoters and provide the structural basis for the initiation of RNA synthesis at positions 1 and 3 of the RSV promoters. These structures offer a deeper understanding of the pre-initiation state of the RSV polymerase and could aid in antiviral research against RSV.
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Affiliation(s)
- Dongdong Cao
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Yunrong Gao
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Zhenhang Chen
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Inesh Gooneratne
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Claire Roesler
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Cristopher Mera
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Paul D'Cunha
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Anna Antonova
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Deepak Katta
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Sarah Romanelli
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Qi Wang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Samantha Rice
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Wesley Lemons
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Anita Ramanathan
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Bo Liang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA.
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11
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Whitehead JD, Decool H, Leyrat C, Carrique L, Fix J, Eléouët JF, Galloux M, Renner M. Structure of the N-RNA/P interface indicates mode of L/P recruitment to the nucleocapsid of human metapneumovirus. Nat Commun 2023; 14:7627. [PMID: 37993464 PMCID: PMC10665349 DOI: 10.1038/s41467-023-43434-5] [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: 06/29/2023] [Accepted: 11/08/2023] [Indexed: 11/24/2023] Open
Abstract
Human metapneumovirus (HMPV) is a major cause of respiratory illness in young children. The HMPV polymerase (L) binds an obligate cofactor, the phosphoprotein (P). During replication and transcription, the L/P complex traverses the viral RNA genome, which is encapsidated within nucleoproteins (N). An essential interaction between N and a C-terminal region of P tethers the L/P polymerase to the template. This N-P interaction is also involved in the formation of cytoplasmic viral factories in infected cells, called inclusion bodies. To define how the polymerase component P recognizes N-encapsidated RNA (N-RNA) we employed cryogenic electron microscopy (cryo-EM) and molecular dynamics simulations, coupled to activity assays and imaging of inclusion bodies in cells. We report a 2.9 Å resolution structure of a triple-complex between multimeric N, bound to both RNA and the C-terminal region of P. Furthermore, we also present cryo-EM structures of assembled N in different oligomeric states, highlighting the plasticity of N. Combined with our functional assays, these structural data delineate in molecular detail how P attaches to N-RNA whilst retaining substantial conformational dynamics. Moreover, the N-RNA-P triple complex structure provides a molecular blueprint for the design of therapeutics to potentially disrupt the attachment of L/P to its template.
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Affiliation(s)
- Jack D Whitehead
- Division of Structural Biology, The Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Hortense Decool
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Cédric Leyrat
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Loic Carrique
- Division of Structural Biology, The Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Jenna Fix
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | | | - Marie Galloux
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France.
| | - Max Renner
- Department of Chemistry, Umeå University, Umeå, Sweden.
- Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.
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12
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Merritt TN, Pei J, Leung DW. Pathogenicity and virulence of human respiratory syncytial virus: Multifunctional nonstructural proteins NS1 and NS2. Virulence 2023:2283897. [PMID: 37964591 DOI: 10.1080/21505594.2023.2283897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 11/09/2023] [Indexed: 11/16/2023] Open
Abstract
Human respiratory syncytial virus (hRSV) is a major cause of acute lower respiratory tract infections in children under the age of two as well as in the elderly and immunocompromised worldwide. Despite its discovery over 60 years ago and the global impact on human health, limited specific and effective prophylactic or therapeutic options have been available for hRSV infections. Part of the lack of treatment options is attributed to the legacy of vaccine failure in the 1960s using a formalin-inactivated RSV (FI-RSV), which led to enhancement of disease post exposure to hRSV infection and hampered subsequent development of vaccine candidates. Recent FDA approval of a vaccine for older adults and impending approval for a maternal vaccine are major advancements but leaves children between 6 months and 5 years of age unprotected. Part of this limitation can be attributed to a lack of complete understanding of the factors that contribute to hRSV pathogenesis. The nonstructural proteins NS1 and NS2 are multifunctional virulence factors that are unique to hRSV and that play critical roles during hRSV infection, including antagonizing interferon (IFN) signalling to modulate host responses to hRSV infection. However, the molecular mechanisms by which the nonstructural proteins mediate their IFN inhibitory functions have not been completely defined. Current progress on the characterization of NS1 and NS2 during infection provides deeper insight into their roles. Furthermore, reverse genetics systems for hRSV provide a viable strategy to generate attenuated viruses by introduction of select mutations while maintaining immunogenicity required to elicit a long-term protective response. Here we will review the current state of knowledge of the nonstructural proteins, their contributions to RSV pathogenesis, and their potential as targets for therapeutic development.
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Affiliation(s)
- Trudy N Merritt
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jingjing Pei
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Daisy W Leung
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
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13
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Yu X, Abeywickrema P, Bonneux B, Behera I, Anson B, Jacoby E, Fung A, Adhikary S, Bhaumik A, Carbajo RJ, De Bruyn S, Miller R, Patrick A, Pham Q, Piassek M, Verheyen N, Shareef A, Sutto-Ortiz P, Ysebaert N, Van Vlijmen H, Jonckers THM, Herschke F, McLellan JS, Decroly E, Fearns R, Grosse S, Roymans D, Sharma S, Rigaux P, Jin Z. Structural and mechanistic insights into the inhibition of respiratory syncytial virus polymerase by a non-nucleoside inhibitor. Commun Biol 2023; 6:1074. [PMID: 37865687 PMCID: PMC10590419 DOI: 10.1038/s42003-023-05451-4] [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: 08/07/2023] [Accepted: 10/11/2023] [Indexed: 10/23/2023] Open
Abstract
The respiratory syncytial virus polymerase complex, consisting of the polymerase (L) and phosphoprotein (P), catalyzes nucleotide polymerization, cap addition, and cap methylation via the RNA dependent RNA polymerase, capping, and Methyltransferase domains on L. Several nucleoside and non-nucleoside inhibitors have been reported to inhibit this polymerase complex, but the structural details of the exact inhibitor-polymerase interactions have been lacking. Here, we report a non-nucleoside inhibitor JNJ-8003 with sub-nanomolar inhibition potency in both antiviral and polymerase assays. Our 2.9 Å resolution cryo-EM structure revealed that JNJ-8003 binds to an induced-fit pocket on the capping domain, with multiple interactions consistent with its tight binding and resistance mutation profile. The minigenome and gel-based de novo RNA synthesis and primer extension assays demonstrated that JNJ-8003 inhibited nucleotide polymerization at the early stages of RNA transcription and replication. Our results support that JNJ-8003 binding modulates a functional interplay between the capping and RdRp domains, and this molecular insight could accelerate the design of broad-spectrum antiviral drugs.
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Affiliation(s)
- Xiaodi Yu
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA.
| | - Pravien Abeywickrema
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Brecht Bonneux
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
- University of Antwerp, Antwerp, Belgium
| | - Ishani Behera
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Brandon Anson
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Edgar Jacoby
- Johnson & Johnson Innovative Medicine, Beerse, Belgium
| | - Amy Fung
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Suraj Adhikary
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Anusarka Bhaumik
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Rodrigo J Carbajo
- Johnson & Johnson Innovative Medicine, Janssen-Cilag, Discovery Chemistry S.A. Río Jarama, 75A, 45007, Toledo, Spain
| | | | - Robyn Miller
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Aaron Patrick
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Quyen Pham
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA
| | - Madison Piassek
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Nick Verheyen
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | - Afzaal Shareef
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, 02118, USA
| | | | - Nina Ysebaert
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | | | | | | | - Jason S McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB, UMR 7257, Marseille, France
| | - Rachel Fearns
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, 02118, USA
| | | | - Dirk Roymans
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | - Sujata Sharma
- Johnson & Johnson Innovative Medicine, Spring House, Pennsylvania, PA, 19477, USA
| | - Peter Rigaux
- Janssen Infectious Diseases and Vaccines, 2340, Beerse, Belgium
| | - Zhinan Jin
- Johnson & Johnson Innovative Medicine, Brisbane, CA, 94005, USA.
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14
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Abstract
The nonsegmented, negative-strand RNA viruses (nsNSVs), also known as the order Mononegavirales, have a genome consisting of a single strand of negative-sense RNA. Integral to the nsNSV replication cycle is the viral polymerase, which is responsible for transcribing the viral genome, to produce an array of capped and polyadenylated messenger RNAs, and replicating it to produce new genomes. To perform the different steps that are necessary for these processes, the nsNSV polymerases undergo a series of coordinated conformational transitions. While much is still to be learned regarding the intersection of nsNSV polymerase dynamics, structure, and function, recently published polymerase structures, combined with a history of biochemical and molecular biology studies, have provided new insights into how nsNSV polymerases function as dynamic machines. In this review, we consider each of the steps involved in nsNSV transcription and replication and suggest how these relate to solved polymerase structures.
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Affiliation(s)
- Mohamed Ouizougun-Oubari
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA;
| | - Rachel Fearns
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA;
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15
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Cadena-Cruz C, Villarreal Camacho JL, De Ávila-Arias M, Hurtado-Gomez L, Rodriguez A, San-Juan-Vergara H. Respiratory syncytial virus entry mechanism in host cells: A general overview. Mol Microbiol 2023; 120:341-350. [PMID: 37537859 DOI: 10.1111/mmi.15133] [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: 04/10/2023] [Revised: 07/05/2023] [Accepted: 07/12/2023] [Indexed: 08/05/2023]
Abstract
Respiratory syncytial virus (RSV) is a virus that causes acute respiratory infections in neonates and older adults. To infect host cells, the attachment glycoprotein (G) interacts with a cell surface receptor. This interaction determines the specific cell types that are susceptible to infection. RSV possesses a type I fusion protein F. Type I fusion proteins are metastable when rearrangement of the prefusion F occurs; the fusion peptide is exposed transforming the protein into postfusion form. The transition between the prefusion form and its postfusion form facilitates the viral envelope and the host cell membrane to fuse, enabling the virus to enter the host cell. Understanding the entry mechanism employed by RSV is crucial for developing effective antiviral therapies. In this review, we will discuss the various types of viral fusion proteins and explore the potential entry mechanisms utilized by RSV. A deeper understanding of these mechanisms will provide valuable insights for the development of novel approaches to treat RSV infections.
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Affiliation(s)
- C Cadena-Cruz
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
- Facultad de Ciencias de la Salud, Programa de Medicina, Universidad Libre Seccional Barranquilla, Barranquilla, Colombia
| | - J L Villarreal Camacho
- Facultad de Ciencias de la Salud, Programa de Medicina, Universidad Libre Seccional Barranquilla, Barranquilla, Colombia
| | - Marcio De Ávila-Arias
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
| | - Leidy Hurtado-Gomez
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
| | - Alexander Rodriguez
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
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16
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Salgueiro M, Camporeale G, Visentin A, Aran M, Pellizza L, Esperante SA, Corbat A, Grecco H, Sousa B, Esperón R, Borkosky SS, de Prat-Gay G. Molten Globule Driven and Self-downmodulated Phase Separation of a Viral Factory Scaffold. J Mol Biol 2023; 435:168153. [PMID: 37210029 DOI: 10.1016/j.jmb.2023.168153] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 05/09/2023] [Accepted: 05/12/2023] [Indexed: 05/22/2023]
Abstract
Viral factories of liquid-like nature serve as sites for transcription and replication in most viruses. The respiratory syncytial virus factories include replication proteins, brought together by the phosphoprotein (P) RNA polymerase cofactor, present across non-segmented negative stranded RNA viruses. Homotypic liquid-liquid phase separation of RSV-P is governed by an α-helical molten globule domain, and strongly self-downmodulated by adjacent sequences. Condensation of P with the nucleoprotein N is stoichiometrically tuned, defining aggregate-droplet and droplet-dissolution boundaries. Time course analysis show small N-P nuclei gradually coalescing into large granules in transfected cells. This behavior is recapitulated in infection, with small puncta evolving to large viral factories, strongly suggesting that P-N nucleation-condensation sequentially drives viral factories. Thus, the tendency of P to undergo phase separation is moderate and latent in the full-length protein but unleashed in the presence of N or when neighboring disordered sequences are deleted. This, together with its capacity to rescue nucleoprotein-RNA aggregates suggests a role as a "solvent-protein".
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Affiliation(s)
- Mariano Salgueiro
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Gabriela Camporeale
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Araceli Visentin
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Martin Aran
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Leonardo Pellizza
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | | | - Agustín Corbat
- Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Buenos Aires, and IFIBA, CONICET, Buenos Aires, Argentina
| | - Hernán Grecco
- Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Buenos Aires, and IFIBA, CONICET, Buenos Aires, Argentina
| | - Belén Sousa
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Ramiro Esperón
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Silvia S Borkosky
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Gonzalo de Prat-Gay
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina.
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17
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Li H, Wu Y, Li M, Guo L, Gao Y, Wang Q, Zhang J, Lai Z, Zhang X, Zhu L, Lan P, Rao Z, Liu Y, Liang H. An intermediate state allows influenza polymerase to switch smoothly between transcription and replication cycles. Nat Struct Mol Biol 2023; 30:1183-1192. [PMID: 37488357 DOI: 10.1038/s41594-023-01043-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 06/23/2023] [Indexed: 07/26/2023]
Abstract
Influenza polymerase (FluPol) transcribes viral mRNA at the beginning of the viral life cycle and initiates genome replication after viral protein synthesis. However, it remains poorly understood how FluPol switches between its transcription and replication states, especially given that the structural bases of these two functions are fundamentally different. Here we propose a mechanism by which FluPol achieves functional switching between these two states through a previously unstudied conformation, termed an 'intermediate state'. Using cryo-electron microscopy, we obtained a structure of the intermediate state of H5N1 FluPol at 3.7 Å, which is characterized by a blocked cap-binding domain and a contracted core region. Structural analysis results suggest that the intermediate state may allow FluPol to transition smoothly into either the transcription or replication state. Furthermore, we show that the formation of the intermediate state is required for both the transcription and replication activities of FluPol, leading us to conclude that the transcription and replication cycles of FluPol are regulated via this intermediate state.
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Affiliation(s)
- Huanhuan Li
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Medicine, Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China
- Department of General Surgery, Guangdong Institute of Gastroenterology, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, Biomedical Innovation Center, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yixi Wu
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Medicine, Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China
| | - Minke Li
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Medicine, Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China
| | - Lu Guo
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yaqi Gao
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China
| | - Quan Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jihua Zhang
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China
| | - Zhaohua Lai
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China
| | - Xing Zhang
- Departments of Biophysics and Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Center of Cryo Electron Microscopy, Zhejiang University School of Medicine, Hangzhou, China
| | - Lixin Zhu
- Department of General Surgery, Guangdong Institute of Gastroenterology, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, Biomedical Innovation Center, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Ping Lan
- Department of General Surgery, Guangdong Institute of Gastroenterology, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, Biomedical Innovation Center, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zihe Rao
- Laboratory of Structural Biology, Tsinghua University, Beijing, China
| | - Yingfang Liu
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Medicine, Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China.
- Department of General Surgery, Guangdong Institute of Gastroenterology, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, Biomedical Innovation Center, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
| | - Huanhuan Liang
- Shenzhen Key Laboratory for Systems Medicine in Inflammatory Diseases, School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-Sen University, Sun Yat-Sen University, Shenzhen, China.
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18
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Kleiner VA, O Fischmann T, Howe JA, Beshore DC, Eddins MJ, Hou Y, Mayhood T, Klein D, Nahas DD, Lucas BJ, Xi H, Murray E, Ma DY, Getty K, Fearns R. Conserved allosteric inhibitory site on the respiratory syncytial virus and human metapneumovirus RNA-dependent RNA polymerases. Commun Biol 2023; 6:649. [PMID: 37337079 DOI: 10.1038/s42003-023-04990-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/26/2023] [Indexed: 06/21/2023] Open
Abstract
Respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) are related RNA viruses responsible for severe respiratory infections and resulting disease in infants, elderly, and immunocompromised adults1-3. Therapeutic small molecule inhibitors that bind to the RSV polymerase and inhibit viral replication are being developed, but their binding sites and molecular mechanisms of action remain largely unknown4. Here we report a conserved allosteric inhibitory site identified on the L polymerase proteins of RSV and HMPV that can be targeted by a dual-specificity, non-nucleoside inhibitor, termed MRK-1. Cryo-EM structures of the inhibitor in complexes with truncated RSV and full-length HMPV polymerase proteins provide a structural understanding of how MRK-1 is active against both viruses. Functional analyses indicate that MRK-1 inhibits conformational changes necessary for the polymerase to engage in RNA synthesis initiation and to transition into an elongation mode. Competition studies reveal that the MRK-1 binding pocket is distinct from that of a capping inhibitor with an overlapping resistance profile, suggesting that the polymerase conformation bound by MRK-1 may be distinct from that involved in mRNA capping. These findings should facilitate optimization of dual RSV and HMPV replication inhibitors and provide insights into the molecular mechanisms underlying their polymerase activities.
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Affiliation(s)
- Victoria A Kleiner
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA
| | | | | | | | | | - Yan Hou
- MRL, Merck & Co., Inc., Rahway, NJ, USA
| | | | | | | | | | - He Xi
- MRL, Merck & Co., Inc., Rahway, NJ, USA
| | | | | | | | - Rachel Fearns
- Department of Virology, Immunology & Microbiology, National Emerging Infectious Diseases Laboratories, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA.
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19
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Xu E, Park S, Calderon J, Cao D, Liang B. In Silico Identification and In Vitro Validation of Repurposed Compounds Targeting the RSV Polymerase. Microorganisms 2023; 11:1608. [PMID: 37375110 DOI: 10.3390/microorganisms11061608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 06/14/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
Respiratory Syncytial Virus (RSV) is the top cause of infant hospitalization globally, with no effective treatments available. Researchers have sought small molecules to target the RNA-dependent RNA Polymerase (RdRP) of RSV, which is essential for replication and transcription. Based on the cryo-EM structure of the RSV polymerase, in silico computational analysis including molecular docking and the protein-ligand simulation of a database, including 6554 molecules, is currently undergoing phases 1-4 of clinical trials and has resulted in the top ten repurposed compound candidates against the RSV polymerase, including Micafungin, Totrombopag, and Verubecestat. We performed the same procedure to evaluate 18 small molecules from previous studies and chose the top four compounds for comparison. Among the top identified repurposed compounds, Micafungin, an antifungal medication, showed significant inhibition and binding affinity improvements over current inhibitors such as ALS-8112 and Ribavirin. We also validated Micafungin's inhibition of the RSV RdRP using an in vitro transcription assay. These findings contribute to RSV drug development and hold promise for broad-spectrum antivirals targeting the non-segmented negative-sense (NNS) RNA viral polymerases, including those of rabies (RABV) and Ebola (EBOV).
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Affiliation(s)
- Eric Xu
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Seohyun Park
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Juan Calderon
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Dongdong Cao
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Bo Liang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
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20
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Visentin A, Demitroff N, Salgueiro M, Borkosky SS, Uversky VN, Camporeale G, de Prat-Gay G. Assembly of the Tripartite and RNA Condensates of the Respiratory Syncytial Virus Factory Proteins In Vitro: Role of the Transcription Antiterminator M 2-1. Viruses 2023; 15:1329. [PMID: 37376628 DOI: 10.3390/v15061329] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
A wide variety of viruses replicate in liquid-like viral factories. Non-segmented negative stranded RNA viruses share a nucleoprotein (N) and a phosphoprotein (P) that together emerge as the main drivers of liquid-liquid phase separation. The respiratory syncytial virus includes the transcription antiterminator M2-1, which binds RNA and maximizes RNA transcriptase processivity. We recapitulate the assembly mechanism of condensates of the three proteins and the role played by RNA. M2-1 displays a strong propensity for condensation by itself and with RNA through the formation of electrostatically driven protein-RNA coacervates based on the amphiphilic behavior of M2-1 and finely tuned by stoichiometry. M2-1 incorporates into tripartite condensates with N and P, modulating their size through an interplay with P, where M2-1 is both client and modulator. RNA is incorporated into the tripartite condensates adopting a heterogeneous distribution, reminiscent of the M2-1-RNA IBAG granules within the viral factories. Ionic strength dependence indicates that M2-1 behaves differently in the protein phase as opposed to the protein-RNA phase, in line with the subcompartmentalization observed in viral factories. This work dissects the biochemical grounds for the formation and fate of the RSV condensates in vitro and provides clues to interrogate the mechanism under the highly complex infection context.
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Affiliation(s)
- Araceli Visentin
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Nicolás Demitroff
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Mariano Salgueiro
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Silvia Susana Borkosky
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Gabriela Camporeale
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Gonzalo de Prat-Gay
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials (CNPEM), Campinas 13083-970, SP, Brazil
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21
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Cong J, Feng X, Kang H, Fu W, Wang L, Wang C, Li X, Chen Y, Rao Z. Structure of the Newcastle Disease Virus L protein in complex with tetrameric phosphoprotein. Nat Commun 2023; 14:1324. [PMID: 36898997 PMCID: PMC10006412 DOI: 10.1038/s41467-023-37012-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 02/27/2023] [Indexed: 03/12/2023] Open
Abstract
Newcastle disease virus (NDV) belongs to Paramyxoviridae, which contains lethal human and animal pathogens. NDV RNA genome is replicated and transcribed by a multifunctional 250 kDa RNA-dependent RNA polymerase (L protein). To date, high-resolution structure of NDV L protein complexed with P protein remains to be elucidated, limiting our understanding of the molecular mechanisms of Paramyxoviridae replication/transcription. Here, we used cryo-EM and enzymatic assays to investigate the structure-function relationship of L-P complex. We found that C-terminal of CD-MTase-CTD module of the atomic-resolution L-P complex conformationally rearranges, and the priming/intrusion loops are likely in RNA elongation conformations different from previous structures. The P protein adopts a unique tetrameric organization and interacts with L protein. Our findings indicate that NDV L-P complex represents elongation state distinct from previous structures. Our work greatly advances the understanding of Paramyxoviridae RNA synthesis, revealing how initiation/elongation alternates, providing clues for identifying therapeutic targets against Paramyxoviridae.
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Affiliation(s)
- Jingyuan Cong
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoying Feng
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Huiling Kang
- Laboratory of Structural Biology, School of Medicine, Tsinghua University, Beijing, China
| | - Wangjun Fu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lei Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chenlong Wang
- Laboratory of Structural Biology, School of Medicine, Tsinghua University, Beijing, China
| | - Xuemei Li
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
| | - Yutao Chen
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
| | - Zihe Rao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- Laboratory of Structural Biology, School of Medicine, Tsinghua University, Beijing, China
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22
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Whitehead JD, Grimes JM, Keown JR. Structural and biophysical characterization of the Borna disease virus 1 phosphoprotein. Acta Crystallogr F Struct Biol Commun 2023; 79:51-60. [PMID: 36862093 PMCID: PMC9979977 DOI: 10.1107/s2053230x23000717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 01/26/2023] [Indexed: 02/25/2023] Open
Abstract
Bornaviruses are RNA viruses with a mammalian, reptilian, and avian host range. The viruses infect neuronal cells and in rare cases cause a lethal encephalitis. The family Bornaviridae are part of the Mononegavirales order of viruses, which contain a nonsegmented viral genome. Mononegavirales encode a viral phosphoprotein (P) that binds both the viral polymerase (L) and the viral nucleoprotein (N). The P protein acts as a molecular chaperone and is required for the formation of a functional replication/transcription complex. In this study, the structure of the oligomerization domain of the phosphoprotein determined by X-ray crystallography is reported. The structural results are complemented with biophysical characterization using circular dichroism, differential scanning calorimetry and small-angle X-ray scattering. The data reveal the phosphoprotein to assemble into a stable tetramer, with the regions outside the oligomerization domain remaining highly flexible. A helix-breaking motif is observed between the α-helices at the midpoint of the oligomerization domain that appears to be conserved across the Bornaviridae. These data provide information on an important component of the bornavirus replication complex.
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Affiliation(s)
- Jack D. Whitehead
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Jonathan M. Grimes
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Jeremy R. Keown
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
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23
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Sutto-Ortiz P, Eléouët JF, Ferron F, Decroly E. Biochemistry of the Respiratory Syncytial Virus L Protein Embedding RNA Polymerase and Capping Activities. Viruses 2023; 15:v15020341. [PMID: 36851554 PMCID: PMC9960070 DOI: 10.3390/v15020341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/12/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023] Open
Abstract
The human respiratory syncytial virus (RSV) is a negative-sense, single-stranded RNA virus. It is the major cause of severe acute lower respiratory tract infection in infants, the elderly population, and immunocompromised individuals. There is still no approved vaccine or antiviral treatment against RSV disease, but new monoclonal prophylactic antibodies are yet to be commercialized, and clinical trials are in progress. Hence, urgent efforts are needed to develop efficient therapeutic treatments. RSV RNA synthesis comprises viral transcription and replication that are catalyzed by the large protein (L) in coordination with the phosphoprotein polymerase cofactor (P), the nucleoprotein (N), and the M2-1 transcription factor. The replication/transcription is orchestrated by the L protein, which contains three conserved enzymatic domains: the RNA-dependent RNA polymerase (RdRp), the polyribonucleotidyl transferase (PRNTase or capping), and the methyltransferase (MTase) domain. These activities are essential for the RSV replicative cycle and are thus considered as attractive targets for the development of therapeutic agents. In this review, we summarize recent findings about RSV L domains structure that highlight how the enzymatic activities of RSV L domains are interconnected, discuss the most relevant and recent antivirals developments that target the replication/transcription complex, and conclude with a perspective on identified knowledge gaps that enable new research directions.
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Affiliation(s)
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, F78350 Jouy en Josas, France
| | - François Ferron
- Aix Marseille Université, CNRS, AFMB, UMR, 7257 Marseille, France
- European Virus Bioinformatics Center, Leutragraben 1, 07743 Jena, Germany
| | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB, UMR, 7257 Marseille, France
- Correspondence:
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24
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Sugrue RJ, Tan BH. Defining the Assembleome of the Respiratory Syncytial Virus. Subcell Biochem 2023; 106:227-249. [PMID: 38159230 DOI: 10.1007/978-3-031-40086-5_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
During respiratory syncytial virus (RSV) particle assembly, the mature RSV particles form as filamentous projections on the surface of RSV-infected cells. The RSV assembly process occurs at the / on the cell surface that is modified by a virus infection, involving a combination of several different host cell factors and cellular processes. This induces changes in the lipid composition and properties of these lipid microdomains, and the virus-induced activation of associated Rho GTPase signaling networks drives the remodeling of the underlying filamentous actin (F-actin) cytoskeleton network. The modified sites that form on the surface of the infected cells form the nexus point for RSV assembly, and in this review chapter, they are referred to as the RSV assembleome. This is to distinguish these unique membrane microdomains that are formed during virus infection from the corresponding membrane microdomains that are present at the cell surface prior to infection. In this article, an overview of the current understanding of the processes that drive the formation of the assembleome during RSV particle assembly is given.
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Affiliation(s)
- Richard J Sugrue
- School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore.
| | - Boon Huan Tan
- LKC School of Medicine, Nanyang Technological University, Singapore, Republic of Singapore
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25
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Cao D, Gooneratne I, Mera C, Vy J, Royal M, Huang B, Park Y, Manjunath A, Liang B. Analysis of Template Variations on RNA Synthesis by Respiratory Syncytial Virus Polymerase. Viruses 2022; 15:47. [PMID: 36680087 PMCID: PMC9863079 DOI: 10.3390/v15010047] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/18/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a significant threat to infants and elderly individuals globally. Currently, there are no effective therapies or treatments for RSV infection because of an insufficient understanding of the RSV viral machinery. In this study, we investigated the effects of the template variations on RNA synthesis by the RSV polymerase through in vitro RNA synthesis assays. We confirmed the previously reported back-priming activity of the RSV polymerase, which is likely due to the secondary structure of the RNA template. We found that the expansion of the hairpin loop size of the RNA template abolishes the RSV polymerase back-priming activity. At the same time, it seemingly does not affect the de novo RNA synthesis activities of the RSV polymerase. Interestingly, our results show that the RSV polymerase also has a new primer-based terminal extension activity that adds nucleotides to the template and primer in a nonspecific manner. We also mapped the impact of the RNA 5' chemical group on its mobility in a urea-denaturing RNA gel shift assay. Overall, these results enhance our knowledge about the RNA synthesis processes of the RSV polymerase and may guide future therapeutic efforts to develop effective antiviral drugs for RSV treatment.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Bo Liang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
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26
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Borna Disease Virus 1 Phosphoprotein Forms a Tetramer and Interacts with Host Factors Involved in DNA Double-Strand Break Repair and mRNA Processing. Viruses 2022; 14:v14112358. [PMID: 36366462 PMCID: PMC9692295 DOI: 10.3390/v14112358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/21/2022] [Accepted: 10/24/2022] [Indexed: 01/31/2023] Open
Abstract
Determining the structural organisation of viral replication complexes and unravelling the impact of infection on cellular homeostasis represent important challenges in virology. This may prove particularly useful when confronted with viruses that pose a significant threat to human health, that appear unique within their family, or for which knowledge is scarce. Among Mononegavirales, bornaviruses (family Bornaviridae) stand out due to their compact genomes and their nuclear localisation for replication. The recent recognition of the zoonotic potential of several orthobornaviruses has sparked a surge of interest in improving our knowledge on this viral family. In this work, we provide a complete analysis of the structural organisation of Borna disease virus 1 (BoDV-1) phosphoprotein (P), an important cofactor for polymerase activity. Using X-ray diffusion and diffraction experiments, we revealed that BoDV-1 P adopts a long coiled-coil α-helical structure split into two parts by an original β-strand twist motif, which is highly conserved across the members of whole Orthobornavirus genus and may regulate viral replication. In parallel, we used BioID to determine the proximal interactome of P in living cells. We confirmed previously known interactors and identified novel proteins linked to several biological processes such as DNA repair or mRNA metabolism. Altogether, our study provides important structure/function cues, which may improve our understanding of BoDV-1 pathogenesis.
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27
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Roe MK, Perez MA, Hsiao HM, Lapp SA, Sun HY, Jadhao S, Young AR, Batista YS, Reed RC, Taz A, Piantadosi A, Chen X, Liang B, Koval M, Snider TA, Moore ML, Anderson EJ, Anderson LJ, Stobart CC, Rostad CA. An RSV Live-Attenuated Vaccine Candidate Lacking G Protein Mucin Domains Is Attenuated, Immunogenic, and Effective in Preventing RSV in BALB/c Mice. J Infect Dis 2022; 227:50-60. [PMID: 36281651 PMCID: PMC9796166 DOI: 10.1093/infdis/jiac382] [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: 05/09/2022] [Revised: 09/09/2022] [Accepted: 10/31/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Respiratory syncytial virus (RSV) is a leading viral respiratory pathogen in infants. The objective of this study was to generate RSV live-attenuated vaccine (LAV) candidates by removing the G-protein mucin domains to attenuate viral replication while retaining immunogenicity through deshielding of surface epitopes. METHODS Two LAV candidates were generated from recombinant RSV A2-line19F by deletion of the G-protein mucin domains (A2-line19F-G155) or deletion of the G-protein mucin and transmembrane domains (A2-line19F-G155S). Vaccine attenuation was measured in BALB/c mouse lungs by fluorescent focus unit (FFU) assays and real-time polymerase chain reaction (RT-PCR). Immunogenicity was determined by measuring serum binding and neutralizing antibodies in mice following prime/boost on days 28 and 59. Efficacy was determined by measuring RSV lung viral loads on day 4 postchallenge. RESULTS Both LAVs were undetectable in mouse lungs by FFU assay and elicited similar neutralizing antibody titers compared to A2-line19F on days 28 and 59. Following RSV challenge, vaccinated mice showed no detectable RSV in the lungs by FFU assay and a significant reduction in RSV RNA in the lungs by RT-PCR of 560-fold for A2-line19F-G155 and 604-fold for A2-line19F-G155S compared to RSV-challenged, unvaccinated mice. CONCLUSIONS Removal of the G-protein mucin domains produced RSV LAV candidates that were highly attenuated with retained immunogenicity.
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Affiliation(s)
- Molly K Roe
- Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA
| | - Maria A Perez
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Hui-Mien Hsiao
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Stacey A Lapp
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - He-Ying Sun
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Samadhan Jadhao
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Audrey R Young
- Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA
| | - Yara S Batista
- Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA
| | - Ryan C Reed
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Azmain Taz
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Anne Piantadosi
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Xuemin Chen
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Bo Liang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Michael Koval
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Timothy A Snider
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, Oklahoma, USA
| | | | - Evan J Anderson
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA,Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Larry J Anderson
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Christina A Rostad
- Correspondence: Christina A. Rostad, MD, Emory Children's Center, 2015 Uppergate Drive NE, Atlanta, GA 30322 ()
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28
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Sourimant J, Lieber CM, Yoon JJ, Toots M, Govindarajan M, Udumula V, Sakamoto K, Natchus MG, Patti J, Vernachio J, Plemper RK. Orally efficacious lead of the AVG inhibitor series targeting a dynamic interface in the respiratory syncytial virus polymerase. SCIENCE ADVANCES 2022; 8:eabo2236. [PMID: 35749502 PMCID: PMC9232112 DOI: 10.1126/sciadv.abo2236] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Respiratory syncytial virus (RSV) is a leading cause of lower respiratory infections in infants and the immunocompromised, yet no efficient therapeutic exists. We have identified the AVG class of allosteric inhibitors of RSV RNA synthesis. Here, we demonstrate through biolayer interferometry and in vitro RNA-dependent RNA polymerase (RdRP) assays that AVG compounds bind to the viral polymerase, stalling the polymerase in initiation conformation. Resistance profiling revealed a unique escape pattern, suggesting a discrete docking pose. Affinity mapping using photoreactive AVG analogs identified the interface of polymerase core, capping, and connector domains as a molecular target site. A first-generation lead showed nanomolar potency against RSV in human airway epithelium organoids but lacked in vivo efficacy. Docking pose-informed synthetic optimization generated orally efficacious AVG-388, which showed potent efficacy in the RSV mouse model when administered therapeutically. This study maps a druggable target in the RSV RdRP and establishes clinical potential of the AVG chemotype against RSV disease.
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Affiliation(s)
- Julien Sourimant
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Carolin M. Lieber
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Jeong-Joong Yoon
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Mart Toots
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | | | - Venkata Udumula
- Emory Institute for Drug Development, Emory University, Atlanta, GA 30322, USA
| | - Kaori Sakamoto
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Michael G. Natchus
- Emory Institute for Drug Development, Emory University, Atlanta, GA 30322, USA
| | - Joseph Patti
- Aviragen Therapeutics Inc, Alpharetta, GA 30009, USA
| | | | - Richard K. Plemper
- Center for Translational Antiviral Research, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
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29
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Amara U, Rashid S, Mahmood K, Nawaz MH, Hayat A, Hassan M. Insight into prognostics, diagnostics, and management strategies for SARS CoV-2. RSC Adv 2022; 12:8059-8094. [PMID: 35424750 PMCID: PMC8982343 DOI: 10.1039/d1ra07988c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 02/04/2022] [Indexed: 01/08/2023] Open
Abstract
The foremost challenge in countering infectious diseases is the shortage of effective therapeutics. The emergence of coronavirus disease (COVID-19) outbreak has posed a great menace to the public health system globally, prompting unprecedented endeavors to contain the virus. Many countries have organized research programs for therapeutics and management development. However, the longstanding process has forced authorities to implement widespread infrastructures for detailed prognostic and diagnostics study of severe acute respiratory syndrome (SARS CoV-2). This review discussed nearly all the globally developed diagnostic methodologies reported for SARS CoV-2 detection. We have highlighted in detail the approaches for evaluating COVID-19 biomarkers along with the most employed nucleic acid- and protein-based detection methodologies and the causes of their severe downfall and rejection. As the variable variants of SARS CoV-2 came into the picture, we captured the breadth of newly integrated digital sensing prototypes comprised of plasmonic and field-effect transistor-based sensors along with commercially available food and drug administration (FDA) approved detection kits. However, more efforts are required to exploit the available resources to manufacture cheap and robust diagnostic methodologies. Likewise, the visualization and characterization tools along with the current challenges associated with waste-water surveillance, food security, contact tracing, and their role during this intense period of the pandemic have also been discussed. We expect that the integrated data will be supportive and aid in the evaluation of sensing technologies not only in current but also future pandemics.
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Affiliation(s)
- Umay Amara
- Institute of Chemical Sciences, Bahauddin Zakariya University Multan 608000 Pakistan
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad Lahore Campus 54000 Pakistan
| | - Sidra Rashid
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad Lahore Campus 54000 Pakistan
| | - Khalid Mahmood
- Institute of Chemical Sciences, Bahauddin Zakariya University Multan 608000 Pakistan
| | - Mian Hasnain Nawaz
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad Lahore Campus 54000 Pakistan
| | - Akhtar Hayat
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad Lahore Campus 54000 Pakistan
| | - Maria Hassan
- Institute of Chemical Sciences, Bahauddin Zakariya University Multan 608000 Pakistan
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30
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Detailed Analyses of Molecular Interactions between Favipiravir and RNA Viruses In Silico. Viruses 2022; 14:v14020338. [PMID: 35215932 PMCID: PMC8879546 DOI: 10.3390/v14020338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 02/01/2022] [Accepted: 02/05/2022] [Indexed: 02/05/2023] Open
Abstract
There are currently no antiviral agents for human metapneumovirus (HMPV), respiratory syncytial virus (RSV), mumps virus (MuV), or measles virus (MeV). Favipiravir has been developed as an anti-influenza agent, and this agent may be effective against these viruses in vitro. However, the molecular mechanisms through which the agent affects virus replication remain to be fully elucidated. Thus, to clarify the detailed molecular interactions between favipiravir and the RNA-dependent RNA polymerase (RdRp) of HMPV, RSV, MuV, MeV, and influenza virus, we performed in silico studies using authentic bioinformatics technologies. As a result, we found that the active form of favipiravir (favipiravir ribofuranosyl-5′-triphosphate [F-RTP]) can bind to the RdRp active sites of HMPV, RSV, MuV, and MeV. The aspartic acid residue of RdRp active sites was involved in the interaction. Moreover, F-RTP was incorporated into the growing viral RNA chain in the presence of nucleotide triphosphate and magnesium ions. The results suggested that favipiravir shows two distinct mechanisms in various viruses: RdRp active site inhibition and/or genome replication inhibition.
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31
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Chen JW, Yang L, Santos C, Hassan SA, Collins PL, Buchholz UJ, Le Nouën C. Reversion mutations in phosphoprotein P of a codon-pair-deoptimized human respiratory syncytial virus confer increased transcription, immunogenicity, and genetic stability without loss of attenuation. PLoS Pathog 2021; 17:e1010191. [PMID: 34965283 PMCID: PMC8751989 DOI: 10.1371/journal.ppat.1010191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 01/11/2022] [Accepted: 12/09/2021] [Indexed: 11/18/2022] Open
Abstract
Recoding viral genomes by introducing numerous synonymous nucleotide substitutions that create suboptimal codon pairs provides new live-attenuated vaccine candidates. Because recoding typically involves a large number of nucleotide substitutions, the risk of de-attenuation is presumed to be low. However, this has not been thoroughly studied. We previously generated human respiratory syncytial virus (RSV) in which the NS1, NS2, N, P, M and SH ORFs were codon-pair deoptimized (CPD) by 695 synonymous nucleotide changes (Min A virus). Min A exhibited a global reduction in transcription and protein synthesis, was restricted for replication in vitro and in vivo, and exhibited moderate temperature sensitivity. Here, we show that under selective pressure by serial passage at progressively increasing temperatures, Min A regained replication fitness and lost its temperature sensitivity. Whole-genome deep sequencing identified numerous missense mutations in several genes, in particular ones accumulating between codons 25 and 34 of the phosphoprotein (P), a polymerase cofactor and chaperone. When re-introduced into Min A, these P mutations restored viral transcription to wt level, resulting in increased protein expression and RNA replication. Molecular dynamic simulations suggested that these P mutations increased the flexibility of the N-terminal domain of P, which might facilitate its interaction with the nucleoprotein N, and increase the functional efficiency of the RSV transcription/replication complex. Finally, we evaluated the effect of the P mutations on Min A replication and immunogenicity in hamsters. Mutation P[F28V] paradoxically reduced Min A replication but not its immunogenicity. The further addition of one missense mutation each in M and L generated a version of Min A with increased genetic stability. Thus, this study provides further insight into the adaptability of large-scale recoded RNA viruses under selective pressure and identified an improved CPD RSV vaccine candidate. Synonymous recoding of viral genomes by codon-pair deoptimization (CPD) generates live-attenuated vaccines presumed to be genetically stable due to the high number of nucleotide substitutions. However, their actual genetic stability under selective pressure was largely unknown. In a recoded human respiratory syncytial virus (RSV) mutant called Min A, six of 11 ORFs were CPD, reducing protein expression and inducing moderate temperature sensitivity and attenuation. When passaged in vitro under selective pressure, Min A lost its temperature-sensitive phenotype and regained fitness by the acquisition of numerous mutations, in particular missense mutations in the viral phosphoprotein (P), a polymerase cofactor and a chaperone for soluble nucleoprotein. These P mutations increased RSV gene transcription globally, thereby increasing RSV protein expression, RNA replication, and virus particle production. Thus, the P mutations increased the efficiency of the RSV transcription/replication complex, compensating for the reduced protein expression due to CPD. In addition, introduction of the P mutations into Min A generated a live-attenuated vaccine candidate with increased genetic stability. Surprisingly, this vaccine candidate exhibited increased attenuation and, paradoxically, exhibited increased immunogenicity per plaque-forming unit in hamsters. This study provides insights into the adaptability of large-scale recoded RNA viruses and identified an improved CPD RSV vaccine candidate.
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Affiliation(s)
- Jessica W. Chen
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Lijuan Yang
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Celia Santos
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Sergio A. Hassan
- Bioinformatics and Computational Biosciences Branch, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Peter L. Collins
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Ursula J. Buchholz
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Cyril Le Nouën
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
- * E-mail:
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Comparison of RNA synthesis initiation properties of non-segmented negative strand RNA virus polymerases. PLoS Pathog 2021; 17:e1010151. [PMID: 34914795 PMCID: PMC8717993 DOI: 10.1371/journal.ppat.1010151] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/30/2021] [Accepted: 11/26/2021] [Indexed: 11/19/2022] Open
Abstract
It is generally thought that the promoters of non-segmented, negative strand RNA viruses (nsNSVs) direct the polymerase to initiate RNA synthesis exclusively opposite the 3´ terminal nucleotide of the genome RNA by a de novo (primer independent) initiation mechanism. However, recent studies have revealed that there is diversity between different nsNSVs with pneumovirus promoters directing the polymerase to initiate at positions 1 and 3 of the genome, and ebolavirus polymerases being able to initiate at position 2 on the template. Studies with other RNA viruses have shown that polymerases that engage in de novo initiation opposite position 1 typically have structural features to stabilize the initiation complex and ensure efficient and accurate initiation. This raised the question of whether different nsNSV polymerases have evolved fundamentally different structural properties to facilitate initiation at different sites on their promoters. Here we examined the functional properties of polymerases of respiratory syncytial virus (RSV), a pneumovirus, human parainfluenza virus type 3 (PIV-3), a paramyxovirus, and Marburg virus (MARV), a filovirus, both on their cognate promoters and on promoters of other viruses. We found that in contrast to the RSV polymerase, which initiated at positions 1 and 3 of its promoter, the PIV-3 and MARV polymerases initiated exclusively at position 1 on their cognate promoters. However, all three polymerases could recognize and initiate from heterologous promoters, with the promoter sequence playing a key role in determining initiation site selection. In addition to examining de novo initiation, we also compared the ability of the RSV and PIV-3 polymerases to engage in back-priming, an activity in which the promoter template is folded into a secondary structure and nucleotides are added to the template 3´ end. This analysis showed that whereas the RSV polymerase was promiscuous in back-priming activity, the PIV-3 polymerase generated barely detectable levels of back-primed product, irrespective of promoter template sequence. Overall, this study shows that the polymerases from these three nsNSV families are fundamentally similar in their initiation properties, but have differences in their abilities to engage in back-priming.
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Jurković M, Slović A, Forčić D, Ivančić-Jelečki J, Košutić-Gulija T, Jagušić M. Influence of Ribavirin on Mumps Virus Population Diversity. Viruses 2021; 13:2535. [PMID: 34960805 PMCID: PMC8706638 DOI: 10.3390/v13122535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/07/2021] [Accepted: 12/12/2021] [Indexed: 12/26/2022] Open
Abstract
Frequent mumps outbreaks in vaccinated populations and the occurrence of neurological complications (e.g., aseptic meningitis or encephalitis) in patients with mumps indicate the need for the development of more efficient vaccines as well as specific antiviral therapies. RNA viruses are genetically highly heterogeneous populations that exist on the edge of an error threshold, such that additional increases in mutational burden can lead to extinction of the virus population. Deliberate modulation of their natural mutation rate is being exploited as an antiviral strategy and a possibility for rational vaccine design. The aim of this study was to examine the ability of ribavirin, a broad-spectrum antiviral agent, to introduce mutations in the mumps virus (MuV) genome and to investigate if resistance develops during long-term in vitro exposure to ribavirin. An increase in MuV population heterogeneity in the presence of ribavirin has been observed after one passage in cell culture, as well as a bias toward C-to-U and G-to-A transitions, which have previously been defined as ribavirin-related. At higher ribavirin concentration, MuV loses its infectivity during serial passaging and does not recover. At low ribavirin concentration, serial passaging leads to a more significant increase in population diversity and a stronger bias towards ribavirin-related transitions, independently of viral strain or cell culture. In these conditions, the virus retains its initial growth capacity, without development of resistance at a whole-virus population level.
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Affiliation(s)
| | | | | | | | | | - Maja Jagušić
- Centre for Research and Knowledge Transfer in Biotechnology, University of Zagreb, Rockefellerova 10, 10000 Zagreb, Croatia; (M.J.); (A.S.); (D.F.); (J.I.-J.); (T.K.-G.)
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Kolakofsky D, Le Mercier P, Nishio M, Blackledge M, Crépin T, Ruigrok RWH. Sendai Virus and a Unified Model of Mononegavirus RNA Synthesis. Viruses 2021; 13:v13122466. [PMID: 34960735 PMCID: PMC8708023 DOI: 10.3390/v13122466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 12/20/2022] Open
Abstract
Vesicular stomatitis virus (VSV), the founding member of the mononegavirus order (Mononegavirales), was found to be a negative strand RNA virus in the 1960s, and since then the number of such viruses has continually increased with no end in sight. Sendai virus (SeV) was noted soon afterwards due to an outbreak of newborn pneumonitis in Japan whose putative agent was passed in mice, and nowadays this mouse virus is mainly the bane of animal houses and immunologists. However, SeV was important in the study of this class of viruses because, like flu, it grows to high titers in embryonated chicken eggs, facilitating the biochemical characterization of its infection and that of its nucleocapsid, which is very close to that of measles virus (MeV). This review and opinion piece follow SeV as more is known about how various mononegaviruses express their genetic information and carry out their RNA synthesis, and proposes a unified model based on what all MNV have in common.
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Affiliation(s)
- Daniel Kolakofsky
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, Medical School, University of Geneva, 1211 Geneva, Switzerland
- Correspondence: (D.K.); (R.W.H.R.)
| | - Philippe Le Mercier
- Swiss-Prot Group, Swiss Institute of Bioinformatics, School of Medicine, University of Geneva, 1211 Geneva, Switzerland;
| | - Machiko Nishio
- Department of Microbiology, School of Medicine, Wakayama Medical University, Wakayama 641-8509, Japan;
| | - Martin Blackledge
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, 38058 Grenoble, France; (M.B.); (T.C.)
| | - Thibaut Crépin
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, 38058 Grenoble, France; (M.B.); (T.C.)
| | - Rob W. H. Ruigrok
- Institut de Biologie Structurale (IBS), CEA, CNRS, Université Grenoble Alpes, 38058 Grenoble, France; (M.B.); (T.C.)
- Correspondence: (D.K.); (R.W.H.R.)
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Pyle JD, Whelan SPJ, Bloyet LM. Structure and function of negative-strand RNA virus polymerase complexes. Enzymes 2021; 50:21-78. [PMID: 34861938 DOI: 10.1016/bs.enz.2021.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Viruses with negative-strand RNA genomes (NSVs) include many highly pathogenic and economically devastating disease-causing agents of humans, livestock, and plants-highlighted by recent Ebola and measles virus epidemics, and continuously circulating influenza virus. Because of their protein-coding orientation, NSVs face unique challenges for efficient gene expression and genome replication. To overcome these barriers, NSVs deliver a large and multifunctional RNA-dependent RNA polymerase into infected host cells. NSV-encoded polymerases contain all the enzymatic activities required for transcription and replication of their genome-including RNA synthesis and mRNA capping. Here, we review the structures and functions of NSV polymerases with a focus on key domains responsible for viral replication and gene expression. We highlight shared and unique features among polymerases of NSVs from the Mononegavirales, Bunyavirales, and Articulavirales orders.
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Affiliation(s)
- Jesse D Pyle
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, United States; Ph.D. Program in Virology, Harvard Medical School, Boston, MA, United States
| | - Sean P J Whelan
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, United States.
| | - Louis-Marie Bloyet
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, United States.
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McClelland RD, Culp TN, Marchant DJ. Imaging Flow Cytometry and Confocal Immunofluorescence Microscopy of Virus-Host Cell Interactions. Front Cell Infect Microbiol 2021; 11:749039. [PMID: 34712624 PMCID: PMC8546218 DOI: 10.3389/fcimb.2021.749039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/27/2021] [Indexed: 11/25/2022] Open
Abstract
Viruses are diverse pathogens that use host factors to enter cells and cause disease. Imaging the entry and replication phases of viruses and their interactions with host factors is key to fully understanding viral infections. This review will discuss how confocal microscopy and imaging flow cytometry are used to investigate virus entry and replication mechanisms in fixed and live cells. Quantification of viral images and the use of cryo-electron microscopy to gather structural information of viruses is also explored. Using imaging to understand how viruses replicate and interact with host factors, we gain insight into cellular processes and identify novel targets to develop antiviral therapeutics and vaccines.
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Affiliation(s)
- Ryley D McClelland
- Department of Medical Microbiology and Immunology, Li Ka Shing Institute of Virology, Katz Center for Health Research, University of Alberta, Edmonton, AB, Canada
| | - Tyce N Culp
- Department of Medical Microbiology and Immunology, Li Ka Shing Institute of Virology, Katz Center for Health Research, University of Alberta, Edmonton, AB, Canada
| | - David J Marchant
- Department of Medical Microbiology and Immunology, Li Ka Shing Institute of Virology, Katz Center for Health Research, University of Alberta, Edmonton, AB, Canada
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Pyasi S, Gupta A, Hegde NR, Nayak D. Complete genome sequencing and assessment of mutation-associated protein dynamics of the first Indian bovine ephemeral fever virus (BEFV) isolate. Vet Q 2021; 41:308-319. [PMID: 34663182 PMCID: PMC8567923 DOI: 10.1080/01652176.2021.1995909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background Bovine ephemeral fever (BEF) is a re-emerging disease caused by bovine ephemeral fever virus (BEFV). Although it poses a huge economic threat to the livestock sector, complete viral genome information from any South Asian country, including India, lacks. Aim Genome characterization of the first Indian BEFV isolate and to evaluate its genetic diversity by characterizing genomic mutations and their associated protein dynamics. Materials and Methods Of the nineteen positive blood samples collected from BEF symptomatic animals during the 2018-19 outbreaks in India, one random sample was used to amplify the entire viral genome by RT-PCR. Utilizing Sanger sequencing and NGS technology, a complete genome was determined. Genome characterization, genetic diversity and phylogenetic analyses were explored by comparing the results with available global isolates. Additionally, unique genomic mutations within the Indian isolate were investigated, followed by in-silico assessment of non-synonymous (NS) mutations impacts on corresponding proteins’ secondary structure, solvent accessibility and dynamics. Results The complete genome of Indian BEFV has 14,903 nucleotides with 33% GC with considerable genetic diversity. Its sequence comparison and phylogenetic analysis revealed a close relatedness to the Middle Eastern lineage. Genome-wide scanning elucidated 30 unique mutations, including 10 NS mutations in the P, L and GNS proteins. The mutational impact evaluation confirmed alterations in protein structure and dynamics, with minimal effect on solvent accessibility. Additionally, alteration in the interatomic interactions was compared against the wild type. Conclusion These findings extend our understanding of the BEFV epidemiological and pathogenic potential, aiding in developing better therapeutic and preventive interventions.
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Affiliation(s)
- Shruti Pyasi
- Discipline of Bioscience and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Advika Gupta
- Discipline of Bioscience and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Nagendra R Hegde
- Department of Biotechnology, National Institute of Animal Biotechnology, Hyderabad, India
| | - Debasis Nayak
- Discipline of Bioscience and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
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Cardone C, Caseau CM, Bardiaux B, Thureaux A, Galloux M, Bajorek M, Eléouët JF, Litaudon M, Bontems F, Sizun C. A Structural and Dynamic Analysis of the Partially Disordered Polymerase-Binding Domain in RSV Phosphoprotein. Biomolecules 2021; 11:biom11081225. [PMID: 34439894 PMCID: PMC8392014 DOI: 10.3390/biom11081225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 12/11/2022] Open
Abstract
The phosphoprotein P of Mononegavirales (MNV) is an essential co-factor of the viral RNA polymerase L. Its prime function is to recruit L to the ribonucleocapsid composed of the viral genome encapsidated by the nucleoprotein N. MNV phosphoproteins often contain a high degree of disorder. In Pneumoviridae phosphoproteins, the only domain with well-defined structure is a small oligomerization domain (POD). We previously characterized the differential disorder in respiratory syncytial virus (RSV) phosphoprotein by NMR. We showed that outside of RSV POD, the intrinsically disordered N-and C-terminal regions displayed a structural and dynamic diversity ranging from random coil to high helical propensity. Here we provide additional insight into the dynamic behavior of PCα, a domain that is C-terminal to POD and constitutes the RSV L-binding region together with POD. By using small phosphoprotein fragments centered on or adjacent to POD, we obtained a structural picture of the POD–PCα region in solution, at the single residue level by NMR and at lower resolution by complementary biophysical methods. We probed POD–PCα inter-domain contacts and showed that small molecules were able to modify the dynamics of PCα. These structural properties are fundamental to the peculiar binding mode of RSV phosphoprotein to L, where each of the four protomers binds to L in a different way.
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Affiliation(s)
- Christophe Cardone
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - Claire-Marie Caseau
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - Benjamin Bardiaux
- Structural Bioinformatics Unit, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3528, 78015 Paris, France;
| | | | - Marie Galloux
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, 78352 Jouy-en-Josas, France; (M.G.); (M.B.); (J.-F.E.)
| | - Monika Bajorek
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, 78352 Jouy-en-Josas, France; (M.G.); (M.B.); (J.-F.E.)
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, 78352 Jouy-en-Josas, France; (M.G.); (M.B.); (J.-F.E.)
| | - Marc Litaudon
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - François Bontems
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - Christina Sizun
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
- Correspondence:
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The Role of Coronavirus RNA-Processing Enzymes in Innate Immune Evasion. Life (Basel) 2021; 11:life11060571. [PMID: 34204549 PMCID: PMC8235370 DOI: 10.3390/life11060571] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 01/21/2023] Open
Abstract
Viral RNA sensing triggers innate antiviral responses in humans by stimulating signaling pathways that include crucial antiviral genes such as interferon. RNA viruses have evolved strategies to inhibit or escape these mechanisms. Coronaviruses use multiple enzymes to synthesize, modify, and process their genomic RNA and sub-genomic RNAs. These include Nsp15 and Nsp16, whose respective roles in RNA capping and dsRNA degradation play a crucial role in coronavirus escape from immune surveillance. Evolutionary studies on coronaviruses demonstrate that genome expansion in Nidoviruses was promoted by the emergence of Nsp14-ExoN activity and led to the acquisition of Nsp15- and Nsp16-RNA-processing activities. In this review, we discuss the main RNA-sensing mechanisms in humans as well as recent structural, functional, and evolutionary insights into coronavirus Nsp15 and Nsp16 with a view to potential antiviral strategies.
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Wang Z, Hou D, Fang J, Zhu L, Sun Y, Tan Y, Gu Z, Shan L. Screening and pharmacodynamic evaluation of the antirespiratory syncytial virus activity of steroidal pyridine compounds in vitro and in vivo. J Med Virol 2021; 93:3428-3438. [PMID: 33064304 DOI: 10.1002/jmv.26604] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 12/31/2022]
Abstract
Respiratory syncytial virus (RSV) causes serious lower respiratory tract infections and there are currently no safer or more effective drugs available. It is important to find novel medications for RSV infection. A series of steroidal pyridines were synthesized for screening and evaluation of their antiviral activity and investigation of their antiviral mechanism of action. Compound 3l had the highest antiviral activity, with a half-maximal effective concentration (EC50 ) of 3.13 μM. Compound 3l was explored for its effects in vitro on RSV 2 h before infection (pretreatment), at the time of infection (competition), and 2 h after infection (postinfection). Toll-like receptor (TLR)-3, retinoic acid-inducible gene (RIG)-I, interleukin (IL)-6, and interferon (IFN)-β were suppressed at the cellular level. Mouse lung tissue was subjected to hematoxylin and eosin (HE) staining and immunohistochemistry, which showed that RSV antigen and M gene expression could be reduced by compound 3l. Decreased expression of TLR-3, RIG-I, IL-6, IFN-β, and IL-10 was also found in vivo. The results indicated that compound 3l exerted its antiviral effects mainly through inhibition of viral replication and downregulation of inflammatory factors.
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Affiliation(s)
- Zhenya Wang
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
| | - Duoduo Hou
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
| | - Jieyu Fang
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
| | - Li Zhu
- Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, China
| | - Yingying Sun
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
| | - Yayun Tan
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
| | - Zichen Gu
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
| | - Lihong Shan
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, Zhengzhou University, Zhengzhou, Henan, China
- Key Laboratory of "Runliang" Antiviral Medicines Research and Development, Institute of Drug Discovery & Development, Zhengzhou University, Zhengzhou, Henan, China
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Structural Insights into the Respiratory Syncytial Virus RNA Synthesis Complexes. Viruses 2021; 13:v13050834. [PMID: 34063087 PMCID: PMC8147935 DOI: 10.3390/v13050834] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/30/2021] [Accepted: 05/02/2021] [Indexed: 12/13/2022] Open
Abstract
RNA synthesis in respiratory syncytial virus (RSV), a negative-sense (-) nonsegmented RNA virus, consists of viral gene transcription and genome replication. Gene transcription includes the positive-sense (+) viral mRNA synthesis, 5'-RNA capping and methylation, and 3' end polyadenylation. Genome replication includes (+) RNA antigenome and (-) RNA genome synthesis. RSV executes the viral RNA synthesis using an RNA synthesis ribonucleoprotein (RNP) complex, comprising four proteins, the nucleoprotein (N), the large protein (L), the phosphoprotein (P), and the M2-1 protein. We provide an overview of the RSV RNA synthesis and the structural insights into the RSV gene transcription and genome replication process. We propose a model of how the essential four proteins coordinate their activities in different RNA synthesis processes.
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Tetramerization of Phosphoprotein is Essential for Respiratory Syncytial Virus Budding while its N Terminal Region Mediates Direct Interactions with the Matrix Protein. J Virol 2021; 95:JVI.02217-20. [PMID: 33408180 PMCID: PMC8092690 DOI: 10.1128/jvi.02217-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
It was shown previously that the Matrix (M), Phosphoprotein (P), and the Fusion (F) proteins of Respiratory syncytial virus (RSV) are sufficient to produce virus-like particles (VLPs) that resemble the RSV infection-induced virions. However, the exact mechanism and interactions among the three proteins are not known. This work examines the interaction between P and M during RSV assembly and budding. We show that M interacts with P in the absence of other viral proteins in cells using a Split Nano Luciferase assay. By using recombinant proteins, we demonstrate a direct interaction between M and P. By using Nuclear Magnetic Resonance (NMR) we identify three novel M interaction sites on P, namely site I in the αN2 region, site II in the 115-125 region, and the oligomerization domain (OD). We show that the OD, and likely the tetrameric structural organization of P, is required for virus-like filament formation and VLP release. Although sites I and II are not required for VLP formation, they appear to modulate P levels in RSV VLPs.Importance Human RSV is the commonest cause of infantile bronchiolitis in the developed world and of childhood deaths in resource-poor settings. It is a major unmet target for vaccines and anti-viral drugs. The lack of knowledge of RSV budding mechanism presents a continuing challenge for VLP production for vaccine purpose. We show that direct interaction between P and M modulates RSV VLP budding. This further emphasizes P as a central regulator of RSV life cycle, as an essential actor for transcription and replication early during infection and as a mediator for assembly and budding in the later stages for virus production.
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Cardone C, Caseau CM, Pereira N, Sizun C. Pneumoviral Phosphoprotein, a Multidomain Adaptor-Like Protein of Apparent Low Structural Complexity and High Conformational Versatility. Int J Mol Sci 2021; 22:ijms22041537. [PMID: 33546457 PMCID: PMC7913705 DOI: 10.3390/ijms22041537] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 01/16/2023] Open
Abstract
Mononegavirales phosphoproteins (P) are essential co-factors of the viral polymerase by serving as a linchpin between the catalytic subunit and the ribonucleoprotein template. They have highly diverged, but their overall architecture is conserved. They are multidomain proteins, which all possess an oligomerization domain that separates N- and C-terminal domains. Large intrinsically disordered regions constitute their hallmark. Here, we exemplify their structural features and interaction potential, based on the Pneumoviridae P proteins. These P proteins are rather small, and their oligomerization domain is the only part with a defined 3D structure, owing to a quaternary arrangement. All other parts are either flexible or form short-lived secondary structure elements that transiently associate with the rest of the protein. Pneumoviridae P proteins interact with several viral and cellular proteins that are essential for viral transcription and replication. The combination of intrinsic disorder and tetrameric organization enables them to structurally adapt to different partners and to act as adaptor-like platforms to bring the latter close in space. Transient structures are stabilized in complex with protein partners. This class of proteins gives an insight into the structural versatility of non-globular intrinsically disordered protein domains.
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44
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Tian L, Qiang T, Liang C, Ren X, Jia M, Zhang J, Li J, Wan M, YuWen X, Li H, Cao W, Liu H. RNA-dependent RNA polymerase (RdRp) inhibitors: The current landscape and repurposing for the COVID-19 pandemic. Eur J Med Chem 2021; 213:113201. [PMID: 33524687 PMCID: PMC7826122 DOI: 10.1016/j.ejmech.2021.113201] [Citation(s) in RCA: 123] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/14/2020] [Accepted: 01/12/2021] [Indexed: 02/06/2023]
Abstract
The widespread nature of several viruses is greatly credited to their rapidly altering RNA genomes that enable the infection to persist despite challenges presented by host cells. Within the RNA genome of infections is RNA-dependent RNA polymerase (RdRp), which is an essential enzyme that helps in RNA synthesis by catalysing the RNA template-dependent development of phosphodiester bonds. Therefore, RdRp is an important therapeutic target in RNA virus-caused diseases, including SARS-CoV-2. In this review, we describe the promising RdRp inhibitors that have been launched or are currently in clinical studies for the treatment of RNA virus infections. Structurally, nucleoside inhibitors (NIs) bind to the RdRp protein at the enzyme active site, and nonnucleoside inhibitors (NNIs) bind to the RdRp protein at allosteric sites. By reviewing these inhibitors, more precise guidelines for the development of more promising anti-RNA virus drugs should be set, and due to the current health emergency, they will eventually be used for COVID-19 treatment.
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Affiliation(s)
- Lei Tian
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China; Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Taotao Qiang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Chengyuan Liang
- Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China.
| | - Xiaodong Ren
- Medical College, Guizhou University, Guiyang, 550025, PR China.
| | - Minyi Jia
- Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Jiayun Zhang
- Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Jingyi Li
- Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Minge Wan
- School of Medicine and Pharmacy, Shaanxi University of Business & Commerce, Xi'an, 712046, PR China
| | - Xin YuWen
- Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Han Li
- Faculty of Pharmacy, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Wenqiang Cao
- Zhuhai Jinan Selenium Source Nanotechnology Co., Ltd., Hengqin New Area, Zhuhai, 519030, PR China.
| | - Hong Liu
- Zhuhai Jinan Selenium Source Nanotechnology Co., Ltd., Hengqin New Area, Zhuhai, 519030, PR China.
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Maheden K, Todd B, Gordon CJ, Tchesnokov EP, Götte M. Inhibition of viral RNA-dependent RNA polymerases with clinically relevant nucleotide analogs. Enzymes 2021; 49:315-354. [PMID: 34696837 PMCID: PMC8517576 DOI: 10.1016/bs.enz.2021.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The treatment of viral infections remains challenging, in particular in the face of emerging pathogens. Broad-spectrum antiviral drugs could potentially be used as a first line of defense. The RNA-dependent RNA polymerase (RdRp) of RNA viruses serves as a logical target for drug discovery and development efforts. Herein we discuss compounds that target RdRp of poliovirus, hepatitis C virus, influenza viruses, respiratory syncytial virus, and the growing data on coronaviruses. We focus on nucleotide analogs and mechanisms of action and resistance.
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Affiliation(s)
- Kieran Maheden
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada; School of Biomedical Engineering, University of British Columbia, Vancouver, BC, Canada
| | - Brendan Todd
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Calvin J Gordon
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Egor P Tchesnokov
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Matthias Götte
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada; Li Ka Shing Institute of Virology at University of Alberta, Edmonton, AB, Canada.
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46
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Abstract
RNA viruses include many important human and animal pathogens, such as the influenza viruses, respiratory syncytial virus, Ebola virus, measles virus and rabies virus. The genomes of these viruses consist of single or multiple RNA segments that assemble with oligomeric viral nucleoprotein into ribonucleoprotein complexes. Replication and transcription of the viral genome is performed by ~250-450 kDa viral RNA-dependent RNA polymerases that also contain capping or cap-snatching activity. In this Review, we compare recent high-resolution X-ray and cryoelectron microscopy structures of RNA polymerases of negative-sense RNA viruses with segmented and non-segmented genomes, including orthomyxoviruses, peribunyaviruses, phenuiviruses, arenaviruses, rhabdoviruses, pneumoviruses and paramyxoviruses. In addition, we discuss how structural insights into these enzymes contribute to our understanding of the molecular mechanisms of viral transcription and replication, and how we can use these insights to identify targets for antiviral drug design.
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47
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Groaz E, De Clercq E, Herdewijn P. Anno 2021: Which antivirals for the coming decade? ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2021; 57:49-107. [PMID: 34744210 PMCID: PMC8563371 DOI: 10.1016/bs.armc.2021.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Despite considerable progress in the development of antiviral drugs, among which anti-immunodeficiency virus (HIV) and anti-hepatitis C virus (HCV) medications can be considered real success stories, many viral infections remain without an effective treatment. This not only applies to infectious outbreaks caused by zoonotic viruses that have recently spilled over into humans such as severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), but also ancient viral diseases that have been brought under control by vaccination such as variola (smallpox), poliomyelitis, measles, and rabies. A largely unsolved problem are endemic respiratory infections due to influenza, respiratory syncytial virus (RSV), and rhinoviruses, whose associated morbidity will likely worsen with increasing air pollution. Furthermore, climate changes will expose industrialized countries to a dangerous resurgence of viral hemorrhagic fevers, which might also become global infections. Herein, we summarize the recent progress that has been made in the search for new antivirals against these different threats that the world population will need to confront with increasing frequency in the next decade.
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Affiliation(s)
- Elisabetta Groaz
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium,Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy,Corresponding author:
| | - Erik De Clercq
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Piet Herdewijn
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
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48
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In Vitro Primer-Based RNA Elongation and Promoter Fine Mapping of the Respiratory Syncytial Virus. J Virol 2020; 95:JVI.01897-20. [PMID: 33028717 PMCID: PMC7737744 DOI: 10.1128/jvi.01897-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 11/20/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a nonsegmented negative-sense (NNS) RNA virus and shares a similar RNA synthesis strategy with other members of NNS RNA viruses, such as measles, rabies virus, and Ebola virus. RSV RNA synthesis is catalyzed by a multifunctional RNA-dependent RNA polymerase (RdRP), which is composed of a large (L) protein that catalyzes three distinct enzymatic functions and an essential coenzyme phosphoprotein (P). Here, we successfully prepared highly pure, full-length, wild-type and mutant RSV polymerase (L-P) complexes. We demonstrated that the RSV polymerase could carry out both de novo and primer-based RNA synthesis. We defined the minimal length of the RNA template for in vitro de novo RNA synthesis using the purified RSV polymerase as 8 nucleotides (nt), shorter than previously reported. We showed that the RSV polymerase catalyzed primer-dependent RNA elongation with different lengths of primers on both short (10-nt) and long (25-nt) RNA templates. We compared the sequence specificity of different viral promoters and identified positions 3, 5, and 8 of the promoter sequence as essential to the in vitro RSV polymerase activity, consistent with the results previously mapped with the in vivo minigenome assay. Overall, these findings agree well with those of previous biochemical studies and extend our understanding of the promoter sequence and the mechanism of RSV RNA synthesis.IMPORTANCE As a major human pathogen, RSV affects 3.4 million children worldwide annually. However, no effective antivirals or vaccines are available. An in-depth mechanistic understanding of the RSV RNA synthesis machinery remains a high priority among the NNS RNA viruses. There is a strong public health need for research on this virus, due to major fundamental gaps in our understanding of NNS RNA virus replication. As the key enzyme executing transcription and replication of the virus, the RSV RdRP is a logical target for novel antiviral drugs. Therefore, exploring the primer-dependent RNA elongation extends our mechanistic understanding of the RSV RNA synthesis. Further fine mapping of the promoter sequence paves the way to better understand the function and structure of the RSV polymerase.
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49
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Stable Attenuation of Human Respiratory Syncytial Virus for Live Vaccines by Deletion and Insertion of Amino Acids in the Hinge Region between the mRNA Capping and Methyltransferase Domains of the Large Polymerase Protein. J Virol 2020; 94:JVI.01831-20. [PMID: 32999025 DOI: 10.1128/jvi.01831-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 09/17/2020] [Indexed: 01/02/2023] Open
Abstract
Human respiratory syncytial virus (RSV) is the leading viral cause of lower respiratory tract disease in infants and children worldwide. Currently, there are no FDA-approved vaccines to combat this virus. The large (L) polymerase protein of RSV replicates the viral genome and transcribes viral mRNAs. The L protein is organized as a core ring-like domain containing the RNA-dependent RNA polymerase and an appendage of globular domains containing an mRNA capping region and a cap methyltransferase region, which are linked by a flexible hinge region. Here, we found that the flexible hinge region of RSV L protein is tolerant to amino acid deletion or insertion. Recombinant RSVs carrying a single or double deletion or a single alanine insertion were genetically stable, highly attenuated in immortalized cells, had defects in replication and spread, and had a delay in innate immune cytokine responses in primary, well-differentiated, human bronchial epithelial (HBE) cultures. The replication of these recombinant viruses was highly attenuated in the upper and lower respiratory tracts of cotton rats. Importantly, these recombinant viruses elicited high levels of neutralizing antibody and provided complete protection against RSV replication. Taken together, amino acid deletions or insertions in the hinge region of the L protein can serve as a novel approach to rationally design genetically stable, highly attenuated, and immunogenic live virus vaccine candidates for RSV.IMPORTANCE Despite tremendous efforts, there are no FDA-approved vaccines for human respiratory syncytial virus (RSV). A live attenuated RSV vaccine is one of the most promising vaccine strategies for RSV. However, it has been a challenge to identify an RSV vaccine strain that has an optimal balance between attenuation and immunogenicity. In this study, we generated a panel of recombinant RSVs carrying a single and double deletion or a single alanine insertion in the large (L) polymerase protein that are genetically stable, sufficiently attenuated, and grow to high titer in cultured cells, while retaining high immunogenicity. Thus, these recombinant viruses may be promising vaccine candidates for RSV.
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50
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The Importance of AGO 1 and 4 in Post-Transcriptional Gene Regulatory Function of tRF5-GluCTC, an Respiratory Syncytial Virus-Induced tRNA-Derived RNA Fragment. Int J Mol Sci 2020; 21:ijms21228766. [PMID: 33233493 PMCID: PMC7699471 DOI: 10.3390/ijms21228766] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/18/2022] Open
Abstract
Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection in infants, the elderly, and immune-compromised patients. It is also a significant contributor to upper respiratory tract infection in the pediatric population. However, its disease mechanisms are still largely unknown. We have recently shown that a tRNA-derived RNA fragment (tRF) from the 5′-end of mature tRNA encoding GluCTC (tRF5-GluCTC), a recently discovered non-coding RNA, is functionally important for RSV replication and host gene regulation at the post-transcriptional level. However, how tRF5-GluCTC carries out the gene regulation is not fully known. In this study, we found that tRF5-GluCTC has impaired gene trans-silencing function in cells deficient of AGO1 or 4, while AGO2 and 3 seem not involved in tRF5-GluCTC-mediated gene regulation. By pulling down individual AGO protein, we discovered that tRF5-GluCTC is detectable only in the AGO4 complex, confirming the essential role of AGO4 in gene regulation and also suggesting that AGO1 contributes to the gene trans-silencing activity of tRF5-GluCTC in an atypical way. We also found that the P protein of RSV is associated with both AGO1 and 4 and AGO4 deficiency leads to reduced infectious viral particles. In summary, this study demonstrates the importance of AGO1 and 4 in mediating the gene trans-silencing function of tRF5-GluCTC.
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