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von Creytz I, Rohde C, Biedenkopf N. The cellular protein phosphatase 2A is a crucial host factor for Marburg virus transcription. J Virol 2024:e0104724. [PMID: 39194238 DOI: 10.1128/jvi.01047-24] [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: 06/17/2024] [Accepted: 07/20/2024] [Indexed: 08/29/2024] Open
Abstract
Little is known regarding the molecular mechanisms that highly pathogenic Marburg virus (MARV) utilizes to transcribe and replicate its genome. Previous studies assumed that dephosphorylation of the filoviral transcription factor VP30 supports transcription, while phosphorylated VP30 reduces transcription. Here, we focused on the role of the host protein phosphatase 2A (PP2A) for VP30 dephosphorylation and promotion of viral transcription. We could show that MARV NP interacts with the subunit B56 of PP2A, as previously shown for the Ebola virus, and that this interaction is important for MARV transcription activity. Inhibition of the interaction between PP2A and NP either by mutating the B56 binding motif encoded on NP, or the use of a PP2A inhibitor, induced VP30 hyperphosphorylation, and as a consequence a decrease of MARV transcription as well as viral growth. These results suggest that NP plays a key role in the dephosphorylation of VP30 by recruiting PP2A. Generation of recombinant (rec) MARV lacking the PP2A-B56 interaction motif on NP was not possible suggesting an essential role of PP2A-mediated VP30 dephosphorylation for the MARV replication cycle. Likewise, we were not able to generate recMARV containing VP30 phosphomimetic mutants indicating that dynamic cycles of VP30 de- and rephosphorylation are a prerequisite for an efficient viral life cycle. As the specific binding motifs of PP2A-B56 and VP30 within NP are highly conserved among the filoviral family, our data suggest a conserved mechanism for filovirus VP30 dephosphorylation by PP2A, revealing the host factor PP2A as a promising target for pan-filoviral therapies. IMPORTANCE Our study elucidates the crucial role of host protein phosphatase 2A (PP2A) in Marburg virus (MARV) transcription. The regulatory subunit B56 of PP2A facilitates VP30 dephosphorylation, and hence transcription activation, via binding to NP. Our results, together with previous data, reveal a conserved mechanism of filovirus VP30 dephosphorylation by host factor PP2A at the NP interface and provide novel insights into potential pan-filovirus therapies.
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Affiliation(s)
- Isabel von Creytz
- Institute of Virology, Philipps-University Marburg, Marburg, Germany
| | - Cornelius Rohde
- Institute of Virology, Philipps-University Marburg, Marburg, Germany
| | - Nadine Biedenkopf
- Institute of Virology, Philipps-University Marburg, Marburg, Germany
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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; 98:e0033224. [PMID: 39078194 PMCID: PMC11334523 DOI: 10.1128/jvi.00332-24] [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] [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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Vucetic A, Lafleur A, Côté M, Kobasa D, Chan M, Alvarez F, Piccirillo C, Dong G, Olivier M. Extracellular vesicle storm during the course of Ebola virus infection in primates. Front Cell Infect Microbiol 2023; 13:1275277. [PMID: 38035334 PMCID: PMC10684970 DOI: 10.3389/fcimb.2023.1275277] [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: 08/09/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023] Open
Abstract
Introduction Ebola virus (EBOV) is an RNA virus of the Filoviridae family that is responsible for outbreaks of hemorrhagic fevers in primates with a lethality rate as high as 90%. EBOV primarily targets host macrophages leading to cell activation and systemic cytokine storm, and fatal infection is associated with an inhibited interferon response, and lymphopenia. The EBOV surface glycoprotein (GP) has been shown to directly induce T cell depletion and can be secreted outside the virion via extracellular vesicles (EVs), though most studies are limited to epithelial cells and underlying mechanisms remain poorly elucidated. Methods To assess the role of GP on EBOV-induced dysregulation of host immunity, we first utilized EBOV virus-like particles (VLPs) expressing VP40 and NP either alone (Bald-VLP) or in conjunction with GP (VLP-GP) to investigate early inflammatory responses in THP-1 macrophages and in a murine model. We then sought to decipher the role of non-classical inflammatory mediators such as EVs over the course of EBOV infection in two EBOV-infected rhesus macaques by isolating and characterizing circulatory EVs throughout disease progression using size exclusion chromatography, nanoparticle tracking-analysis, and LC-MS/MS. Results While all VLPs could induce inflammatory mediators and recruit small peritoneal macrophages, pro-inflammatory cytokine and chemokine gene expression was exacerbated by the presence of GP. Further, quantification of EVs isolated from infected rhesus macaques revealed that the concentration of vesicles peaked in circulation at the terminal stage, at which time EBOV GP could be detected in host-derived exosomes. Moreover, comparative proteomics conducted across EV populations isolated from serum at various time points before and after infection revealed differences in host-derived protein content that were most significantly pronounced at the endpoint of infection, including significant expression of mediators of TLR4 signaling. Discussion These results suggest a dynamic role for EVs in the modification of disease states in the context of EBOV. Overall, our work highlights the importance of viral factors, such as the GP, and host derived EVs in the inflammatory cascade and pathogenesis of EBOV, which can be collectively further exploited for novel antiviral development.
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Affiliation(s)
- Andrea Vucetic
- Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| | - Andrea Lafleur
- Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| | - Marceline Côté
- Department of Biochemistry, Microbiology and Immunology and Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, ON, Canada
| | - Darwyn Kobasa
- Special Pathogen Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB, Canada
| | - Mable Chan
- Special Pathogen Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Fernando Alvarez
- Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
- Federation of Clinical Immunology (FOCiS) Centres of Excellence in Translational Immunology (CETI), Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| | - Ciriaco Piccirillo
- Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
- Federation of Clinical Immunology (FOCiS) Centres of Excellence in Translational Immunology (CETI), Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| | - George Dong
- Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| | - Martin Olivier
- Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
- Federation of Clinical Immunology (FOCiS) Centres of Excellence in Translational Immunology (CETI), Research Institute of the McGill University Health Centre, Montréal, QC, Canada
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4
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Wu C, Wagner ND, Moyle AB, Feng A, Sharma N, Stubbs SH, Donahue C, Davey RA, Gross ML, Leung DW, Amarasinghe GK. Disruption of Ebola NP 0VP35 Inclusion Body-like Structures reduce Viral Infection. J Mol Biol 2023; 435:168241. [PMID: 37598728 PMCID: PMC11312838 DOI: 10.1016/j.jmb.2023.168241] [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: 01/04/2023] [Revised: 08/04/2023] [Accepted: 08/11/2023] [Indexed: 08/22/2023]
Abstract
Viral inclusion bodies (IBs) are potential sites of viral replication and assembly. How viral IBs form remains poorly defined. Here we describe a combined biophysical and cellular approach to identify the components necessary for IB formation during Ebola virus (EBOV) infection. We find that the eNP0VP35 complex containing Ebola nucleoprotein (eNP) and viral protein 35 (eVP35), the functional equivalents of nucleoprotein (N) and phosphoprotein (P) in non-segmented negative strand viruses (NNSVs), phase separates to form inclusion bodies. Phase separation of eNP0VP35 is reversible and modulated by ionic strength. The multivalency of eVP35, and not eNP, is also critical for phase separation. Furthermore, overexpression of an eVP35 peptide disrupts eNP0VP35 complex formation, leading to reduced frequency of IB formation and limited viral infection. Together, our results show that upon EBOV infection, the eNP0VP35 complex forms the minimum unit to drive IB formation and viral replication.
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Affiliation(s)
- Chao Wu
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
| | - Nicole D Wagner
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA; Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Austin B Moyle
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Annie Feng
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Nitin Sharma
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Sarah H Stubbs
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University, Boston, MA, USA
| | - Callie Donahue
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University, Boston, MA, USA
| | - Robert A Davey
- Department of Microbiology, National Emerging Infectious Diseases Laboratories, Boston University, Boston, MA, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Daisy W Leung
- Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
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5
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Mihalič F, Benz C, Kassa E, Lindqvist R, Simonetti L, Inturi R, Aronsson H, Andersson E, Chi CN, Davey NE, Överby AK, Jemth P, Ivarsson Y. Identification of motif-based interactions between SARS-CoV-2 protein domains and human peptide ligands pinpoint antiviral targets. Nat Commun 2023; 14:5636. [PMID: 37704626 PMCID: PMC10499821 DOI: 10.1038/s41467-023-41312-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 08/30/2023] [Indexed: 09/15/2023] Open
Abstract
The virus life cycle depends on host-virus protein-protein interactions, which often involve a disordered protein region binding to a folded protein domain. Here, we used proteomic peptide phage display (ProP-PD) to identify peptides from the intrinsically disordered regions of the human proteome that bind to folded protein domains encoded by the SARS-CoV-2 genome. Eleven folded domains of SARS-CoV-2 proteins were found to bind 281 peptides from human proteins, and affinities of 31 interactions involving eight SARS-CoV-2 protein domains were determined (KD ∼ 7-300 μM). Key specificity residues of the peptides were established for six of the interactions. Two of the peptides, binding Nsp9 and Nsp16, respectively, inhibited viral replication. Our findings demonstrate how high-throughput peptide binding screens simultaneously identify potential host-virus interactions and peptides with antiviral properties. Furthermore, the high number of low-affinity interactions suggest that overexpression of viral proteins during infection may perturb multiple cellular pathways.
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Affiliation(s)
- Filip Mihalič
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Caroline Benz
- Department of Chemistry - BMC, Uppsala University, Box 576, Husargatan 3, 751 23, Uppsala, Sweden
| | - Eszter Kassa
- Department of Chemistry - BMC, Uppsala University, Box 576, Husargatan 3, 751 23, Uppsala, Sweden
| | - Richard Lindqvist
- Department of Clinical Microbiology, Umeå University, 90185, Umeå, Sweden
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, 90187, Umeå, Sweden
| | - Leandro Simonetti
- Department of Chemistry - BMC, Uppsala University, Box 576, Husargatan 3, 751 23, Uppsala, Sweden
| | - Raviteja Inturi
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Hanna Aronsson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Eva Andersson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Celestine N Chi
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Norman E Davey
- Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London, SW3 6JB, UK
| | - Anna K Överby
- Department of Clinical Microbiology, Umeå University, 90185, Umeå, Sweden
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, 90187, Umeå, Sweden
| | - Per Jemth
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden.
| | - Ylva Ivarsson
- Department of Chemistry - BMC, Uppsala University, Box 576, Husargatan 3, 751 23, Uppsala, Sweden.
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6
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Zheng K, Ren Z, Wang Y. Serine-arginine protein kinases and their targets in viral infection and their inhibition. Cell Mol Life Sci 2023; 80:153. [PMID: 37198350 PMCID: PMC10191411 DOI: 10.1007/s00018-023-04808-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/10/2023] [Accepted: 05/12/2023] [Indexed: 05/19/2023]
Abstract
Accumulating evidence has consolidated the interaction between viral infection and host alternative splicing. Serine-arginine (SR) proteins are a class of highly conserved splicing factors critical for the spliceosome maturation, alternative splicing and RNA metabolism. Serine-arginine protein kinases (SRPKs) are important kinases that specifically phosphorylate SR proteins to regulate their distribution and activities in the central pre-mRNA splicing and other cellular processes. In addition to the predominant SR proteins, other cytoplasmic proteins containing a serine-arginine repeat domain, including viral proteins, have been identified as substrates of SRPKs. Viral infection triggers a myriad of cellular events in the host and it is therefore not surprising that viruses explore SRPKs-mediated phosphorylation as an important regulatory node in virus-host interactions. In this review, we briefly summarize the regulation and biological function of SRPKs, highlighting their involvement in the infection process of several viruses, such as viral replication, transcription and capsid assembly. In addition, we review the structure-function relationships of currently available inhibitors of SRPKs and discuss their putative use as antivirals against well-characterized viruses or newly emerging viruses. We also highlight the viral proteins and cellular substrates targeted by SRPKs as potential antiviral therapeutic candidates.
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Affiliation(s)
- Kai Zheng
- School of Pharmacy, Shenzhen University Medical School, Shenzhen, 518055, China.
| | - Zhe Ren
- Institute of Biomedicine, College of Life Science and Technology, Guangdong Province Key Laboratory of Bioengineering Medicine, Key Laboratory of Innovative Technology Research On Natural Products and Cosmetics Raw Materials, Jinan University, Guangzhou, 510632, China
| | - Yifei Wang
- Institute of Biomedicine, College of Life Science and Technology, Guangdong Province Key Laboratory of Bioengineering Medicine, Key Laboratory of Innovative Technology Research On Natural Products and Cosmetics Raw Materials, Jinan University, Guangzhou, 510632, China
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7
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Inhibiting the transcription and replication of Ebola viruses by disrupting the nucleoprotein and VP30 protein interaction with small molecules. Acta Pharmacol Sin 2023:10.1038/s41401-023-01055-0. [PMID: 36759643 PMCID: PMC9909651 DOI: 10.1038/s41401-023-01055-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 01/10/2023] [Indexed: 02/11/2023] Open
Abstract
Ebola virus (EBOV) causes hemorrhagic fever in humans with high morbidity and fatality. Although over 45 years have passed since the first EBOV outbreak, small molecule drugs are not yet available. Ebola viral protein VP30 is a unique RNA synthesis cofactor, and the VP30/NP interaction plays a critical role in initiating the transcription and propagation of EBOV. Here, we designed a high-throughput screening technique based on a competitive binding assay to bind VP30 between an NP-derived peptide and a chemical compound. By screening a library of 8004 compounds, we obtained two lead compounds, Embelin and Kobe2602. The binding of these compounds to the VP30-NP interface was validated by dose-dependent competitive binding assay, surface plasmon resonance, and thermal shift assay. Moreover, the compounds were confirmed to inhibit the transcription and replication of the Ebola genome by a minigenome assay. Similar results were obtained for their two respective analogs (8-gingerol and Kobe0065). Interestingly, these two structurally different molecules exhibit synergistic binding to the VP30/NP interface. The antiviral efficacy (EC50) increased from 1 μM by Kobe0065 alone to 351 nM when Kobe0065 and Embelin were combined in a 4:1 ratio. The synergistic anti-EBOV effect provides a strong incentive for further developing these lead compounds in future studies.
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8
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Madhu P, Davey NE, Ivarsson Y. How viral proteins bind short linear motifs and intrinsically disordered domains. Essays Biochem 2022; 66:EBC20220047. [PMID: 36504386 DOI: 10.1042/ebc20220047] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 02/11/2024]
Abstract
Viruses are the obligate intracellular parasites that exploit the host cellular machinery to replicate their genome. During the viral life cycle viruses manipulate the host cell through interactions with host proteins. Many of these protein-protein interactions are mediated through the recognition of host globular domains by short linear motifs (SLiMs), or longer intrinsically disordered domains (IDD), in the disordered regions of viral proteins. However, viruses also employ their own globular domains for binding to SLiMs and IDDs present in host proteins or virus proteins. In this review, we focus on the different strategies adopted by viruses to utilize proteins or protein domains for binding to the disordered regions of human or/and viral ligands. With a set of examples, we describe viral domains that bind human SLiMs. We also provide examples of viral proteins that bind to SLiMs, or IDDs, of viral proteins as a part of complex assembly and regulation of protein functions. The protein-protein interactions are often crucial for viral replication, and may thus offer possibilities for innovative inhibitor design.
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Affiliation(s)
- Priyanka Madhu
- Department of Chemistry, BMC, Uppsala University, Uppsala, Sweden
| | - Norman E Davey
- Division of Cancer Biology, The Institute of Cancer Research, London, U.K
| | - Ylva Ivarsson
- Department of Chemistry, BMC, Uppsala University, Uppsala, Sweden
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9
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Sun W, Luan F, Wang J, Ma L, Li X, Yang G, Hao C, Qin X, Dong S. Structural insights into the interactions between lloviu virus VP30 and nucleoprotein. Biochem Biophys Res Commun 2022; 616:82-88. [PMID: 35649303 DOI: 10.1016/j.bbrc.2022.05.059] [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: 04/16/2022] [Accepted: 05/17/2022] [Indexed: 11/19/2022]
Abstract
The family Filoviridae comprises many notorious viruses, such as Ebola virus (EBOV) and Marburg virus (MARV), that can infect humans and nonhuman primates. Lloviu virus (LLOV), a less well studied filovirus, is considered a potential pathogen for humans. The VP30 C-terminal domain (CTD) of these filoviruses exhibits nucleoprotein (NP) binding and plays an essential role in viral transcription, replication and assembly. In this study, we confirmed the interactions between LLOV VP30 CTD and its NP fragment, and also determined the crystal structure of the chimeric dimeric LLOV NP-VP30 CTD at 2.50 Å resolution. The structure is highly conserved across the family Filoviridae. While in the dimer structure, only one VP30 CTD binds the NP fragment, which indicates that the interaction between LLOV VP30 CTD and NP is not strong. Our work provides a preliminary model to investigate the interactions between LLOV VP30 and NP and suggests a potential target for anti-filovirus drug development.
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Affiliation(s)
- Weiyan Sun
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Fuchen Luan
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Jiajia Wang
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Lin Ma
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Xiuxiu Li
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan, China
| | - Gongxian Yang
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan, China
| | - Chenyang Hao
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Xiaochun Qin
- School of Biological Science and Technology, University of Jinan, Jinan, China; School of Chemistry and Chemical Engineering, University of Jinan, Jinan, China.
| | - Shishang Dong
- School of Biological Science and Technology, University of Jinan, Jinan, China.
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10
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Abstract
Filovirus-infected cells are characterized by typical cytoplasmic inclusion bodies (IBs) located in the perinuclear region. The formation of these IBs is induced mainly by the accumulation of the filoviral nucleoprotein NP, which recruits the other nucleocapsid proteins, the polymerase co-factor VP35, the polymerase L, the transcription factor VP30 and VP24 via direct or indirect protein-protein interactions. Replication of the negative-strand RNA genomes by the viral polymerase L and VP35 occurs in the IBs, resulting in the synthesis of positive-strand genomes, which are encapsidated by NP, thus forming ribonucleoprotein complexes (antigenomic RNPs). These newly formed antigenomic RNPs in turn serve as templates for the synthesis of negative-strand RNA genomes that are also encapsidated by NP (genomic RNPs). Still in the IBs, genomic RNPs mature into tightly packed transport-competent nucleocapsids (NCs) by the recruitment of the viral protein VP24. NCs are tightly coiled left-handed helices whose structure is mainly determined by the multimerization of NP at its N-terminus, and these helices form the inner layer of the NCs. The RNA genome is fixed by 2 lobes of the NP N-terminus and is thus guided by individual NP molecules along the turns of the helix. Direct interaction of the NP C-terminus with the VP35 and VP24 molecules forms the outer layer of the NCs. Once formed, NCs that are located at the border of the IBs recruit actin polymerization machinery to one of their ends to drive their transport to budding sites for their envelopment and final release. Here, we review the current knowledge on the structure, assembly, and transport of filovirus NCs.
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Affiliation(s)
- Olga Dolnik
- Institute of Virology, Philipps-University Marburg, Marburg, Germany
| | - Stephan Becker
- Institute of Virology, Philipps-University Marburg, Marburg, Germany
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11
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Bach S, Demper JC, Klemm P, Schlereth J, Lechner M, Schoen A, Kämper L, Weber F, Becker S, Biedenkopf N, Hartmann RK. Identification and characterization of short leader and trailer RNAs synthesized by the Ebola virus RNA polymerase. PLoS Pathog 2021; 17:e1010002. [PMID: 34699554 PMCID: PMC8547711 DOI: 10.1371/journal.ppat.1010002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 10/04/2021] [Indexed: 11/21/2022] Open
Abstract
Transcription of non-segmented negative sense (NNS) RNA viruses follows a stop-start mechanism and is thought to be initiated at the genome’s very 3’-end. The synthesis of short abortive leader transcripts (leaderRNAs) has been linked to transcription initiation for some NNS viruses. Here, we identified the synthesis of abortive leaderRNAs (as well as trailer RNAs) that are specifically initiated opposite to (anti)genome nt 2; leaderRNAs are predominantly terminated in the region of nt ~ 60–80. LeaderRNA synthesis requires hexamer phasing in the 3’-leader promoter. We determined a steady-state NP mRNA:leaderRNA ratio of ~10 to 30-fold at 48 h after Ebola virus (EBOV) infection, and this ratio was higher (70 to 190-fold) for minigenome-transfected cells. LeaderRNA initiation at nt 2 and the range of termination sites were not affected by structure and length variation between promoter elements 1 and 2, nor the presence or absence of VP30. Synthesis of leaderRNA is suppressed in the presence of VP30 and termination of leaderRNA is not mediated by cryptic gene end (GE) signals in the 3’-leader promoter. We further found different genomic 3’-end nucleotide requirements for transcription versus replication, suggesting that promoter recognition is different in the replication and transcription mode of the EBOV polymerase. We further provide evidence arguing against a potential role of EBOV leaderRNAs as effector molecules in innate immunity. Taken together, our findings are consistent with a model according to which leaderRNAs are abortive replicative RNAs whose synthesis is not linked to transcription initiation. Rather, replication and transcription complexes are proposed to independently initiate RNA synthesis at separate sites in the 3’-leader promoter, i.e., at the second nucleotide of the genome 3’-end and at the more internally positioned transcription start site preceding the first gene, respectively, as reported for Vesicular stomatitis virus. The RNA polymerase (RdRp) of Ebola virus (EBOV) initiates RNA synthesis at the 3’-leader promoter of its encapsidated, non-segmented negative sense (NNS) RNA genome, either at the penultimate 3’-end position of the genome in the replicative mode or more internally (position 56) at the transcription start site (TSS) in its transcription mode. Here we identified the synthesis of abortive replicative RNAs that are specifically initiated opposite to genome nt 2 (termed leaderRNAs) and predominantly terminated in the region of nt ~ 60–80 near the TSS. The functional role of abortive leaderRNA synthesis is still enigmatic; a role in interferon induction could be excluded. Our findings indirectly link leaderRNA termination to nucleoprotein (NP) availability for encapsidation of nascent replicative RNA or to NP removal from the template RNA. Our findings further argue against the model that leaderRNA synthesis is a prerequisite for each transcription initiation event at the TSS. Rather, our findings are in line with the existence of distinct replicase and transcriptase complexes of RdRp that interact differently with the 3’-leader promoter and intiate RNA synthesis independently at different sites (position 2 or 56 of the genome), mechanistically similar to another NNS virus, Vesicular stomatitis virus.
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Affiliation(s)
- Simone Bach
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marburg, Germany
| | - Jana-Christin Demper
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marburg, Germany
| | - Paul Klemm
- Zentrum für Synthetische Mikrobiologie, Philipps-Universität Marburg, Marburg, Germany
| | - Julia Schlereth
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marburg, Germany
| | - Marcus Lechner
- Zentrum für Synthetische Mikrobiologie, Philipps-Universität Marburg, Marburg, Germany
| | - Andreas Schoen
- Institut für Virologie, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Lennart Kämper
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
| | - Friedemann Weber
- Institut für Virologie, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Stephan Becker
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
| | - Nadine Biedenkopf
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
- * E-mail: (NB); (RKH)
| | - Roland K. Hartmann
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marburg, Germany
- * E-mail: (NB); (RKH)
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12
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Structural and Functional Aspects of Ebola Virus Proteins. Pathogens 2021; 10:pathogens10101330. [PMID: 34684279 PMCID: PMC8538763 DOI: 10.3390/pathogens10101330] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 01/14/2023] Open
Abstract
Ebola virus (EBOV), member of genus Ebolavirus, family Filoviridae, have a non-segmented, single-stranded RNA that contains seven genes: (a) nucleoprotein (NP), (b) viral protein 35 (VP35), (c) VP40, (d) glycoprotein (GP), (e) VP30, (f) VP24, and (g) RNA polymerase (L). All genes encode for one protein each except GP, producing three pre-proteins due to the transcriptional editing. These pre-proteins are translated into four products, namely: (a) soluble secreted glycoprotein (sGP), (b) Δ-peptide, (c) full-length transmembrane spike glycoprotein (GP), and (d) soluble small secreted glycoprotein (ssGP). Further, shed GP is released from infected cells due to cleavage of GP by tumor necrosis factor α-converting enzyme (TACE). This review presents a detailed discussion on various functional aspects of all EBOV proteins and their residues. An introduction to ebolaviruses and their life cycle is also provided for clarity of the available analysis. We believe that this review will help understand the roles played by different EBOV proteins in the pathogenesis of the disease. It will help in targeting significant protein residues for therapeutic and multi-protein/peptide vaccine development.
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13
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Ganaie SS, Schwarz MM, McMillen CM, Price DA, Feng AX, Albe JR, Wang W, Miersch S, Orvedahl A, Cole AR, Sentmanat MF, Mishra N, Boyles DA, Koenig ZT, Kujawa MR, Demers MA, Hoehl RM, Moyle AB, Wagner ND, Stubbs SH, Cardarelli L, Teyra J, McElroy A, Gross ML, Whelan SPJ, Doench J, Cui X, Brett TJ, Sidhu SS, Virgin HW, Egawa T, Leung DW, Amarasinghe GK, Hartman AL. Lrp1 is a host entry factor for Rift Valley fever virus. Cell 2021; 184:5163-5178.e24. [PMID: 34559985 DOI: 10.1016/j.cell.2021.09.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 04/29/2021] [Accepted: 09/01/2021] [Indexed: 12/26/2022]
Abstract
Rift Valley fever virus (RVFV) is a zoonotic pathogen with pandemic potential. RVFV entry is mediated by the viral glycoprotein (Gn), but host entry factors remain poorly defined. Our genome-wide CRISPR screen identified low-density lipoprotein receptor-related protein 1 (mouse Lrp1/human LRP1), heat shock protein (Grp94), and receptor-associated protein (RAP) as critical host factors for RVFV infection. RVFV Gn directly binds to specific Lrp1 clusters and is glycosylation independent. Exogenous addition of murine RAP domain 3 (mRAPD3) and anti-Lrp1 antibodies neutralizes RVFV infection in taxonomically diverse cell lines. Mice treated with mRAPD3 and infected with pathogenic RVFV are protected from disease and death. A mutant mRAPD3 that binds Lrp1 weakly failed to protect from RVFV infection. Together, these data support Lrp1 as a host entry factor for RVFV infection and define a new target to limit RVFV infections.
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Affiliation(s)
- Safder S Ganaie
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Madeline M Schwarz
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Cynthia M McMillen
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - David A Price
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Annie X Feng
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Joseph R Albe
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Wenjie Wang
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Shane Miersch
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Anthony Orvedahl
- Department of Pediatrics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Aidan R Cole
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Monica F Sentmanat
- Genome Engineering and iPSC Center (GEiC), Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Nawneet Mishra
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Devin A Boyles
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Zachary T Koenig
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael R Kujawa
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Matthew A Demers
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ryan M Hoehl
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Austin B Moyle
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicole D Wagner
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Sarah H Stubbs
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Lia Cardarelli
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Joan Teyra
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Anita McElroy
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pediatrics, Division of Pediatric Infectious Disease, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Sean P J Whelan
- Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MO, USA
| | - John Doench
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Xiaoxia Cui
- Genome Engineering and iPSC Center (GEiC), Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Tom J Brett
- Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Sachdev S Sidhu
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Herbert W Virgin
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA; Current address: Vir Biotechnology, San Francisco, CA, USA
| | - Takeshi Egawa
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA; Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
| | - Amy L Hartman
- Center for Vaccine Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA.
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14
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Banerjee G, Shokeen K, Chakraborty N, Agarwal S, Mitra A, Kumar S, Banerjee P. Modulation of immune response in Ebola virus disease. Curr Opin Pharmacol 2021; 60:158-167. [PMID: 34425392 DOI: 10.1016/j.coph.2021.07.004] [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: 04/04/2021] [Revised: 06/29/2021] [Accepted: 07/13/2021] [Indexed: 10/20/2022]
Abstract
Ebola virus disease targets and destroys immune cells, including macrophages and dendritic cells, leading to impairment of host response. After infection, a combination of strategies including alteration and evasion of immune response culminating in a strong inflammatory response can lead to multi-organ failure and death in most infected patients. This review discusses immune response dynamics, mainly focusing on how Ebola manipulates innate and adaptive immune responses and strategizes to thwart host immune responses. We also discuss the challenges and prospects of developing therapeutics and vaccines against Ebola.
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Affiliation(s)
- Goutam Banerjee
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Kamal Shokeen
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Nilanjan Chakraborty
- Department of Microbiology, Adamas University, Kolkata, West Bengal, 700126, India
| | - Saumya Agarwal
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Arindam Mitra
- Department of Microbiology, Adamas University, Kolkata, West Bengal, 700126, India.
| | - Sachin Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India.
| | - Pratik Banerjee
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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15
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Batra J, Mori H, Small GI, Anantpadma M, Shtanko O, Mishra N, Zhang M, Liu D, Williams CG, Biedenkopf N, Becker S, Gross ML, Leung DW, Davey RA, Amarasinghe GK, Krogan NJ, Basler CF. Non-canonical proline-tyrosine interactions with multiple host proteins regulate Ebola virus infection. EMBO J 2021; 40:e105658. [PMID: 34260076 DOI: 10.15252/embj.2020105658] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/23/2021] [Accepted: 07/09/2021] [Indexed: 01/08/2023] Open
Abstract
The Ebola virus VP30 protein interacts with the viral nucleoprotein and with host protein RBBP6 via PPxPxY motifs that adopt non-canonical orientations, as compared to other proline-rich motifs. An affinity tag-purification mass spectrometry approach identified additional PPxPxY-containing host proteins hnRNP L, hnRNPUL1, and PEG10, as VP30 interactors. hnRNP L and PEG10, like RBBP6, inhibit viral RNA synthesis and EBOV infection, whereas hnRNPUL1 enhances. RBBP6 and hnRNP L modulate VP30 phosphorylation, increase viral transcription, and exert additive effects on viral RNA synthesis. PEG10 has more modest inhibitory effects on EBOV replication. hnRNPUL1 positively affects viral RNA synthesis but in a VP30-independent manner. Binding studies demonstrate variable capacity of the PPxPxY motifs from these proteins to bind VP30, define PxPPPPxY as an optimal binding motif, and identify the fifth proline and the tyrosine as most critical for interaction. Competition binding and hydrogen-deuterium exchange mass spectrometry studies demonstrate that each protein binds a similar interface on VP30. VP30 therefore presents a novel proline recognition domain that is targeted by multiple host proteins to modulate viral transcription.
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Affiliation(s)
- Jyoti Batra
- J. David Gladstone Institutes, San Francisco, CA, USA.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA.,Quantitative Biosciences Institute, University of California, San Francisco, CA, USA
| | - Hiroyuki Mori
- Department of Microbiology, NEIDL, Boston University School of Medicine, Boston, MA, USA
| | - Gabriel I Small
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.,John T. Milliken Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Manu Anantpadma
- Department of Microbiology, NEIDL, Boston University School of Medicine, Boston, MA, USA
| | - Olena Shtanko
- Host-Pathogen Interactions, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Nawneet Mishra
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Mengru Zhang
- Department of Chemistry, Washington University School of Medicine, St. Louis, MO, USA
| | - Dandan Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Caroline G Williams
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA
| | - Nadine Biedenkopf
- Institute of Virology, Philipps University of Marburg, Marburg, Germany
| | - Stephan Becker
- Institute of Virology, Philipps University of Marburg, Marburg, Germany
| | - Michael L Gross
- Department of Chemistry, Washington University School of Medicine, St. Louis, MO, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.,John T. Milliken Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Robert A Davey
- Department of Microbiology, NEIDL, Boston University School of Medicine, Boston, MA, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Nevan J Krogan
- J. David Gladstone Institutes, San Francisco, CA, USA.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA.,Quantitative Biosciences Institute, University of California, San Francisco, CA, USA
| | - Christopher F Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA
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16
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Bach S, Demper JC, Grünweller A, Becker S, Biedenkopf N, Hartmann RK. Regulation of VP30-Dependent Transcription by RNA Sequence and Structure in the Genomic Ebola Virus Promoter. J Virol 2021; 95:JVI.02215-20. [PMID: 33268520 PMCID: PMC8092829 DOI: 10.1128/jvi.02215-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 11/22/2020] [Indexed: 01/16/2023] Open
Abstract
Viral transcription and replication of Ebola virus (EBOV) is balanced by transcription factor VP30, an RNA binding protein. An RNA hairpin at the transcription start site (TSS) of the first gene (NP hairpin) in the 3'-leader promoter is thought to mediate the VP30 dependency of transcription. Here, we investigated the constraints of VP30 dependency using a series of monocistronic minigenomes with sequence, structure and length deviations from the native NP hairpin. Hairpin stabilizations decreased while destabilizations increased transcription in the absence of VP30, but in all cases, transcription activity was higher in the presence versus absence of VP30. This also pertains to a mutant that is unable to form any RNA secondary structure at the TSS, demonstrating that the activity of VP30 is not simply determined by the capacity to form a hairpin structure at the TSS. Introduction of continuous 3'-UN5 hexamer phasing between promoter elements PE1 and PE2 by a single point mutation in the NP hairpin boosted VP30-independent transcription. Moreover, this point mutation, but also hairpin stabilizations, impaired the relative increase of replication in the absence of VP30. Our results suggest that the native NP hairpin is optimized for tight regulation by VP30 while avoiding an extent of hairpin stability that impairs viral transcription, as well as for enabling the switch from transcription to replication when VP30 is not part of the polymerase complex.IMPORTANCE A detailed understanding is lacking how the Ebola virus (EBOV) protein VP30 regulates activity of the viral polymerase complex. Here, we studied how RNA sequence, length and structure at the transcription start site (TSS) in the 3'-leader promoter influence the impact of VP30 on viral polymerase activity. We found that hairpin stabilizations tighten the VP30 dependency of transcription but reduce transcription efficiency and attenuate the switch to replication in the absence of VP30. Upon hairpin destabilization, VP30-independent transcription - already weakly detectable at the native promoter - increases, but never reaches the same extent as in the presence of VP30. We conclude that the native hairpin structure involving the TSS (i) establishes an optimal balance between efficient transcription and tight regulation by VP30, (ii) is linked to hexamer phasing in the promoter, and (iii) favors the switch to replication when VP30 is absent.
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Affiliation(s)
- Simone Bach
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35037 Marburg, Germany
| | - Jana-Christin Demper
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35037 Marburg, Germany
| | - Arnold Grünweller
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35037 Marburg, Germany
| | - Stephan Becker
- Institut für Virologie, Philipps-Universität Marburg, Hans-Meerwein-Str. 2, 35043 Marburg
| | - Nadine Biedenkopf
- Institut für Virologie, Philipps-Universität Marburg, Hans-Meerwein-Str. 2, 35043 Marburg
| | - Roland K Hartmann
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35037 Marburg, Germany
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17
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Dinesh DC, Tamilarasan S, Rajaram K, Bouřa E. Antiviral Drug Targets of Single-Stranded RNA Viruses Causing Chronic Human Diseases. Curr Drug Targets 2021; 21:105-124. [PMID: 31538891 DOI: 10.2174/1389450119666190920153247] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/08/2019] [Accepted: 08/08/2019] [Indexed: 02/08/2023]
Abstract
Ribonucleic acid (RNA) viruses associated with chronic diseases in humans are major threats to public health causing high mortality globally. The high mutation rate of RNA viruses helps them to escape the immune response and also is responsible for the development of drug resistance. Chronic infections caused by human immunodeficiency virus (HIV) and hepatitis viruses (HBV and HCV) lead to acquired immunodeficiency syndrome (AIDS) and hepatocellular carcinoma respectively, which are one of the major causes of human deaths. Effective preventative measures to limit chronic and re-emerging viral infections are absolutely necessary. Each class of antiviral agents targets a specific stage in the viral life cycle and inhibits them from its development and proliferation. Most often, antiviral drugs target a specific viral protein, therefore only a few broad-spectrum drugs are available. This review will be focused on the selected viral target proteins of pathogenic viruses containing single-stranded (ss) RNA genome that causes chronic infections in humans (e.g. HIV, HCV, Flaviviruses). In the recent past, an exponential increase in the number of available three-dimensional protein structures (>150000 in Protein Data Bank), allowed us to better understand the molecular mechanism of action of protein targets and antivirals. Advancements in the in silico approaches paved the way to design and develop several novels, highly specific small-molecule inhibitors targeting the viral proteins.
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Affiliation(s)
| | - Selvaraj Tamilarasan
- Section of Microbial Biotechnology, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Kaushik Rajaram
- Department of Microbiology, Central University of Tamil Nadu, Thiruvarur, India
| | - Evžen Bouřa
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
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18
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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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19
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Wu L, Jin D, Wang D, Jing X, Gong P, Qin Y, Chen M. The two-stage interaction of Ebola virus VP40 with nucleoprotein results in a switch from viral RNA synthesis to virion assembly/budding. Protein Cell 2020; 13:120-140. [PMID: 33141416 PMCID: PMC8783937 DOI: 10.1007/s13238-020-00764-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 07/06/2020] [Indexed: 11/28/2022] Open
Abstract
Ebola virus (EBOV) is an enveloped negative-sense RNA virus and a member of the filovirus family. Nucleoprotein (NP) expression alone leads to the formation of inclusion bodies (IBs), which are critical for viral RNA synthesis. The matrix protein, VP40, not only plays a critical role in virus assembly/budding, but also can regulate transcription and replication of the viral genome. However, the molecular mechanism by which VP40 regulates viral RNA synthesis and virion assembly/budding is unknown. Here, we show that within IBs the N-terminus of NP recruits VP40 and is required for VLP-containing NP release. Furthermore, we find four point mutations (L692A, P697A, P698A and W699A) within the C-terminal hydrophobic core of NP result in a stronger VP40-NP interaction within IBs, sequestering VP40 within IBs, reducing VP40-VLP egress, abolishing the incorporation of NC-like structures into VP40-VLP, and inhibiting viral RNA synthesis, suggesting that the interaction of N-terminus of NP with VP40 induces a conformational change in the C-terminus of NP. Consequently, the C-terminal hydrophobic core of NP is exposed and binds VP40, thereby inhibiting RNA synthesis and initiating virion assembly/budding.
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Affiliation(s)
- Linjuan Wu
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Dongning Jin
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Dan Wang
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xuping Jing
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Peng Gong
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yali Qin
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| | - Mingzhou Chen
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
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20
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Whitfield ZJ, Prasad AN, Ronk AJ, Kuzmin IV, Ilinykh PA, Andino R, Bukreyev A. Species-Specific Evolution of Ebola Virus during Replication in Human and Bat Cells. Cell Rep 2020; 32:108028. [PMID: 32814037 PMCID: PMC7434439 DOI: 10.1016/j.celrep.2020.108028] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 05/12/2020] [Accepted: 07/22/2020] [Indexed: 12/13/2022] Open
Abstract
Ebola virus (EBOV) causes a severe, often fatal disease in humans and nonhuman primates. Within the past decade, EBOV has caused two large and difficult-to-control outbreaks, one of which recently ended in the Democratic Republic of the Congo. Bats are the likely reservoir of EBOV, but little is known of their relationship with the virus. We perform serial passages of EBOV in human and bat cells and use circular sequencing to compare the short-term evolution of the virus. Virus populations passaged in bat cells have sequence markers indicative of host RNA editing enzyme activity, including evidence for ADAR editing of the EBOV glycoprotein. Multiple regions in the EBOV genome appear to have undergone adaptive evolution when passaged in bat and human cells. Individual mutated viruses are rescued and characterized. Our results provide insight into the host species-specific evolution of EBOV and highlight the adaptive flexibility of the virus.
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Affiliation(s)
- Zachary J Whitfield
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA
| | - Abhishek N Prasad
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA
| | - Adam J Ronk
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA
| | - Ivan V Kuzmin
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA
| | - Philipp A Ilinykh
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA
| | - Raul Andino
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA.
| | - Alexander Bukreyev
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Department Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA.
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21
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Fragment screening targeting Ebola virus nucleoprotein C-terminal domain identifies lead candidates. Antiviral Res 2020; 180:104822. [PMID: 32446802 PMCID: PMC7894038 DOI: 10.1016/j.antiviral.2020.104822] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/08/2020] [Accepted: 05/15/2020] [Indexed: 01/24/2023]
Abstract
The Ebola Virus is a causative agent of viral hemorrhagic fever outbreaks and a potential global health risk. The outbreak in West Africa (2013-2016) led to 11,000+ deaths and 30,000+ Ebola infected individuals. The current outbreak in the Democratic Republic of Congo (DRC) with 3000+ confirmed cases and 2000+ deaths attributed to Ebola virus infections provides a reminder that innovative countermeasures are still needed. Ebola virus encodes 7 open reading frames (ORFs). Of these, the nucleocapsid protein (eNP) encoded by the first ORF plays many significant roles, including a role in viral RNA synthesis. Here we describe efforts to target the C-terminal domain of eNP (eNP-CTD) that contains highly conserved residues 641-739 as a pan-Ebola antiviral target. Interactions of eNP-CTD with Ebola Viral Protein 30 (eVP30) and Viral Protein 40 (eVP40) have been shown to be crucial for viral RNA synthesis, virion formation, and virion transport. We used nuclear magnetic response (NMR)-based methods to screened the eNP-CTD against a fragment library. Perturbations of 1D 1H NMR spectra identified of 48 of the 439 compounds screened as potential eNP CTD interactors. Subsequent analysis of these compounds to measure chemical shift perturbations in 2D 1H,15N NMR spectra of 15N-labeled protein identified six with low millimolar affinities. All six perturbed an area consisting mainly of residues at or near the extreme C-terminus that we named "Site 1" while three other sites were perturbed by other compounds. Our findings here demonstrate the potential utility of eNP as a target, several fragment hits, and provide an experimental pipeline to validate viral-viral interactions as potential panfiloviral inhibitor targets.
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22
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Miyake T, Farley CM, Neubauer BE, Beddow TP, Hoenen T, Engel DA. Ebola Virus Inclusion Body Formation and RNA Synthesis Are Controlled by a Novel Domain of Nucleoprotein Interacting with VP35. J Virol 2020; 94:e02100-19. [PMID: 32493824 PMCID: PMC7394894 DOI: 10.1128/jvi.02100-19] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 05/24/2020] [Indexed: 12/15/2022] Open
Abstract
Ebola virus (EBOV) inclusion bodies (IBs) are cytoplasmic sites of nucleocapsid formation and RNA replication, housing key steps in the virus life cycle that warrant further investigation. During infection, IBs display dynamic properties regarding their size and location. The contents of IBs also must transition prior to further viral maturation, assembly, and release, implying additional steps in IB function. Interestingly, the expression of the viral nucleoprotein (NP) alone is sufficient for the generation of IBs, indicating that it plays an important role in IB formation during infection. In addition to NP, other components of the nucleocapsid localize to IBs, including VP35, VP24, VP30, and the RNA polymerase L. We previously defined and solved the crystal structure of the C-terminal domain of NP (NP-Ct), but its role in virus replication remained unclear. Here, we show that NP-Ct is necessary for IB formation when NP is expressed alone. Interestingly, we find that NP-Ct is also required for the production of infectious virus-like particles (VLPs), and that defective VLPs with NP-Ct deletions are significantly reduced in viral RNA content. Furthermore, coexpression of the nucleocapsid component VP35 overcomes deletion of NP-Ct in triggering IB formation, demonstrating a functional interaction between the two proteins. Of all the EBOV proteins, only VP35 is able to overcome the defect in IB formation caused by the deletion of NP-Ct. This effect is mediated by a novel protein-protein interaction between VP35 and NP that controls both regulation of IB formation and RNA replication itself and that is mediated by a newly identified functional domain of NP, the central domain.IMPORTANCE Inclusion bodies (IBs) are cytoplasmic sites of RNA synthesis for a variety of negative-sense RNA viruses, including Ebola virus. In addition to housing important steps in the viral life cycle, IBs protect new viral RNA from innate immune attack and contain specific host proteins whose function is under study. A key viral factor in Ebola virus IB formation is the nucleoprotein, NP, which also is important in RNA encapsidation and synthesis. In this study, we have identified two domains of NP that control inclusion body formation. One of these, the central domain (CD), interacts with viral protein VP35 to control both inclusion body formation and RNA synthesis. The other is the NP C-terminal domain (NP-Ct), whose function has not previously been reported. These findings contribute to a model in which NP and its interactions with VP35 link the establishment of IBs to the synthesis of viral RNA.
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Affiliation(s)
- Tsuyoshi Miyake
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Charlotte M Farley
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Benjamin E Neubauer
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Thomas P Beddow
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Thomas Hoenen
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Daniel A Engel
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
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23
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Dong S, Wen K, Chu H, Li H, Yu Q, Wang C, Qin X. Crystal structure of the Měnglà virus VP30 C-terminal domain. Biochem Biophys Res Commun 2020; 525:392-397. [PMID: 32093889 DOI: 10.1016/j.bbrc.2020.02.089] [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: 02/08/2020] [Accepted: 02/12/2020] [Indexed: 11/26/2022]
Abstract
The family Filoviridae contains many important human viruses, including Marburg virus (MARV) and Ebola virus (EBOV). Měnglà virus (MLAV), a newly discovered filovirus, is considered a potential human pathogen. The VP30 C-terminal domain (CTD) of these filoviruses plays an essential role in virion assembly. In common with other filoviruses, MLAV VP30 CTD mainly exists as a dimer in solution. In this work, we determined the crystal structure of recombinant MLAV VP30 CTD monomer, verifying that C-terminal helix-7 (H7) is critical for the dimerization process. This study provides a preliminary model for investigation of MLAV VP30 CTD as an anti-filovirus drug development target.
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Affiliation(s)
- Shishang Dong
- School of Biological Science and Technology, University of Jinan, Jinan, China.
| | - Kangning Wen
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Hongguan Chu
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Hui Li
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Qianqian Yu
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Changhui Wang
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Xiaochun Qin
- School of Biological Science and Technology, University of Jinan, Jinan, China.
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24
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Abstract
The largest Ebola virus (EBOV) epidemic in West Africa ever caused more than 28,000 cases and 11,000 deaths, and the current EBOV epidemic in the Democratic Republic of the Congo continues, with more than 3,000 cases to date. Therefore, it is essential to develop antivirals against EBOV. Recently, an inhibitor of the cellular phosphatase PP2A-mediated dephosphorylation of the EBOV transcription factor VP30 has been shown to suppress the spread of Ebola virus. Here, we identified the protein kinase SRPK1 as a VP30-specific kinase that phosphorylates serine 29, the same residue that is dephosphorylated by PP2A. SRPK1-mediated phosphorylation of serine 29 enabled primary viral transcription. Mutation of the SRPK1 recognition motif in VP30 resulted in significant growth inhibition of EBOV. Similarly, elevation of the phosphorylation status of serine 29 by overexpression of SRPK1 inhibited EBOV growth, highlighting the importance of reversible phosphorylation of VP30 as a potential therapeutic target. Ebola virus (EBOV) causes a severe and often fatal disease for which no approved vaccines or antivirals are currently available. EBOV VP30 has been described as a viral phosphoprotein, and nonphosphorylated VP30 is essential and sufficient to support secondary transcription in an EBOV-specific minigenome system; however, phosphorylatable serine residues near the N terminus of VP30 are required to support primary viral transcription as well as the reinitiation of VP30-mediated transcription at internal EBOV genes. While the dephosphorylation of VP30 by the cellular phosphatase PP2A was found to be mediated by nucleoprotein, the VP30-specific kinases and the role of phosphorylation remain unknown. Here, we report that serine-arginine protein kinase 1 (SRPK1) and SRPK2 phosphorylate serine 29 of VP30, which is located in an N-terminal R26xxS29 motif. Interaction with VP30 via the R26xxS29 motif recruits SRPK1 into EBOV-induced inclusion bodies, the sites of viral RNA synthesis, and an inhibitor of SRPK1/SRPK2 downregulates primary viral transcription. When the SRPK1 recognition motif of VP30 was mutated in a recombinant EBOV, virus replication was severely impaired. It is presumed that the interplay between SRPK1 and PP2A in the EBOV inclusions provides a comprehensive regulatory circuit to ensure the activity of VP30 in EBOV transcription. Thus, the identification of SRPK1 is an important mosaic stone that completes our picture of the players involved in Ebola virus transcription regulation.
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25
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Chen J, He Z, Yuan Y, Huang F, Luo B, Zhang J, Pan T, Zhang H, Zhang J. Host factor SMYD3 is recruited by Ebola virus nucleoprotein to facilitate viral mRNA transcription. Emerg Microbes Infect 2020; 8:1347-1360. [PMID: 31516086 PMCID: PMC6758638 DOI: 10.1080/22221751.2019.1662736] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The polymerase complex of Ebola virus (EBOV) is the functional unit for transcription and replication of viral genome. Nucleoprotein (NP) is a multifunctional protein with high RNA binding affinity and recruits other viral proteins to form functional polymerase complex. In our study, we investigated host proteins associated with EBOV polymerase complex using NP as bait in a transcription and replication competent minigenome system by mass spectrometry analysis and identified SET and MYND domain-containing protein 3 (SMYD3) as a novel host protein which was required for the replication of EBOV. SMYD3 specifically interacted with NP and was recruited to EBOV inclusion bodies through NP. The depletion of SMYD3 dramatically suppressed EBOV mRNA production. A mimic of non-phosphorylated VP30, which is a transcription activator, could partially rescue the viral mRNA production downregulated by the depletion of SMYD3. In addition, SMYD3 promoted NP-VP30 interaction in a dose-dependent manner. These results revealed that SMYD3 was a novel host factor recruited by NP to supporting EBOV mRNA transcription through increasing the binding of VP30 to NP. Thus, our study provided a new understanding of mechanism underlying the transcription of EBOV genome, and a novel anti-EBOV drug design strategy by targeting SMYD3.
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Affiliation(s)
- Jingliang Chen
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Zhangping He
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Yaochang Yuan
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Feng Huang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China.,Department of Respiration, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Baohong Luo
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Jianhua Zhang
- CAS Key Laboratory for Pathogenic Microbiology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , People's Republic of China
| | - Ting Pan
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Hui Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
| | - Junsong Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou , People's Republic of China
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26
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Venkatesan A, Ravichandran L, Dass JFP. Computational Drug Design against Ebola Virus Targeting Viral Matrix Protein VP30. BORNEO JOURNAL OF PHARMACY 2019. [DOI: 10.33084/bjop.v2i2.836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Ebola viral disease (EVD) is a deadly infectious hemorrhagic viral fever caused by the Ebola virus with a high mortality rate. Until date, there is no effective drug or vaccination available to combat this condition. This study focuses on designing an effective antiviral drug for Ebola viral disease targeting viral protein 30 (VP30) of Ebola virus, highly required for transcription initiation. The lead molecules were screened for Lipinski rule of five, ADMET study following which molecular docking and bioactivity prediction was carried out. The compounds with the least binding energy were analyzed using interaction software. The results revealed that 6-Hydroxyluteolin and (-)-Arctigenin represent active lead compounds that inhibit the activity of VP30 protein and exhibits efficient pharmacokinetics. Both these compounds are plant-derived flavonoids and possess no known adverse effects on human health. In addition, they bind strongly to the predicted binding site centered on Lys180, suggesting that these two lead molecules can be imperative in designing a potential drug for EVD.
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27
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Hume AJ, Mühlberger E. Distinct Genome Replication and Transcription Strategies within the Growing Filovirus Family. J Mol Biol 2019; 431:4290-4320. [PMID: 31260690 PMCID: PMC6879820 DOI: 10.1016/j.jmb.2019.06.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/31/2019] [Accepted: 06/24/2019] [Indexed: 11/18/2022]
Abstract
Research on filoviruses has historically focused on the highly pathogenic ebola- and marburgviruses. Indeed, until recently, these were the only two genera in the filovirus family. Recent advances in sequencing technologies have facilitated the discovery of not only a new ebolavirus, but also three new filovirus genera and a sixth proposed genus. While two of these new genera are similar to the ebola- and marburgviruses, the other two, discovered in saltwater fishes, are considerably more diverse. Nonetheless, these viruses retain a number of key features of the other filoviruses. Here, we review the key characteristics of filovirus replication and transcription, highlighting similarities and differences between the viruses. In particular, we focus on key regulatory elements in the genomes, replication and transcription strategies, and the conservation of protein domains and functions among the viruses. In addition, using computational analyses, we were able to identify potential homology and functions for some of the genes of the novel filoviruses with previously unknown functions. Although none of the newly discovered filoviruses have yet been isolated, initial studies of some of these viruses using minigenome systems have yielded insights into their mechanisms of replication and transcription. In general, the Cuevavirus and proposed Dianlovirus genera appear to follow the transcription and replication strategies employed by the ebola- and marburgviruses, respectively. While our knowledge of the fish filoviruses is currently limited to sequence analysis, the lack of certain conserved motifs and even entire genes necessitates that they have evolved distinct mechanisms of replication and transcription.
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Affiliation(s)
- Adam J Hume
- Department of Microbiology, Boston University School of Medicine, Boston, MA 02118, USA; National Emerging Infectious Diseases Laboratories, Boston University, Boston, MA 02118, USA
| | - Elke Mühlberger
- Department of Microbiology, Boston University School of Medicine, Boston, MA 02118, USA; National Emerging Infectious Diseases Laboratories, Boston University, Boston, MA 02118, USA.
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28
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Lee W, Tonelli M, Wu C, Aceti DJ, Amarasinghe GK, Markley JL. Backbone resonance assignments and secondary structure of Ebola nucleoprotein 600-739 construct. BIOMOLECULAR NMR ASSIGNMENTS 2019; 13:315-319. [PMID: 31076990 PMCID: PMC6715526 DOI: 10.1007/s12104-019-09898-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 05/06/2019] [Indexed: 06/09/2023]
Abstract
Ebola viral infections have resulted in several deadly epidemics in recent years in West and Central Africa. Because only one of the seven proteins encoded by the viral genome possesses enzymatic activity, disruption of protein-protein interactions is a promising route for antiviral drug development. We carried out a screening campaign to identify small, drug-like compounds that bind to the C-terminal region of the multifunctional Ebola nucleoprotein (eNP) with the objective of discovering ones that disrupt its binding to other Ebola proteins or to the single-stranded RNA genome. In the course of this effort we assigned the backbone 1H, 15N, and 13C resonances of residues 600‒739, the region that contains the critical eVP30 binding region 600‒615 targeted by host factors, and used the assigned chemical shifts to predict secondary structural features and peptide dynamics. This work supports and extends the previous X-ray crystal structures and NMR studies of residues 641‒739. We found that the 600‒739 domain consists of separate regions that are largely disordered and ordered.
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Affiliation(s)
- Woonghee Lee
- National Magnetic Resonance Facility at Madison, and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison, and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Chao Wu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - David J Aceti
- National Magnetic Resonance Facility at Madison, and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - John L Markley
- National Magnetic Resonance Facility at Madison, and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA.
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29
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Amatya P, Wagner N, Chen G, Luthra P, Shi L, Borek D, Pavlenco A, Rohrs H, Basler CF, Sidhu SS, Gross ML, Leung DW. Inhibition of Marburg Virus RNA Synthesis by a Synthetic Anti-VP35 Antibody. ACS Infect Dis 2019; 5:1385-1396. [PMID: 31120240 DOI: 10.1021/acsinfecdis.9b00091] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Marburg virus causes sporadic outbreaks of severe hemorrhagic fever with high case fatality rates. Approved, effective, and safe therapeutic or prophylactic countermeasures are lacking. To address this, we used phage display to engineer a synthetic antibody, sFab H3, which binds the Marburg virus VP35 protein (mVP35). mVP35 is a critical cofactor of the viral replication complex and a viral immune antagonist. sFab H3 displayed high specificity for mVP35 and not for the closely related Ebola virus VP35. sFab H3 inhibited viral-RNA synthesis in a minigenome assay, suggesting its potential use as an antiviral. We characterized sFab H3 by a combination of biophysical and biochemical methods, and a crystal structure of the complex solved to 1.7 Å resolution defined the molecular interface between the sFab H3 and mVP35 interferon inhibitory domain. Our study identifies mVP35 as a therapeutic target using an approach that provides a framework for generating engineered Fabs targeting other viral proteins.
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Affiliation(s)
- Parmeshwar Amatya
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri 63110, United States
- Department of Pathology and Immunology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri 63110, United States
| | - Nicole Wagner
- Department of Chemistry, Washington University in St. Louis, 1 Brookings Drive, St. Louis, Missouri 63130, United States
| | - Gang Chen
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 816-160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Priya Luthra
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, 100 Piedmont Avenue, Atlanta, Georgia 30303, United States
| | - Liuqing Shi
- Department of Chemistry, Washington University in St. Louis, 1 Brookings Drive, St. Louis, Missouri 63130, United States
| | - Dominika Borek
- Department of Biophysics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, United States
| | - Alevtina Pavlenco
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 816-160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Henry Rohrs
- Department of Chemistry, Washington University in St. Louis, 1 Brookings Drive, St. Louis, Missouri 63130, United States
| | - Christopher F. Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, 100 Piedmont Avenue, Atlanta, Georgia 30303, United States
| | - Sachdev S. Sidhu
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 816-160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Michael L. Gross
- Department of Chemistry, Washington University in St. Louis, 1 Brookings Drive, St. Louis, Missouri 63130, United States
| | - Daisy W. Leung
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri 63110, United States
- Department of Pathology and Immunology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri 63110, United States
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30
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Wu NC, Ward AB. Deception through Mimicry: A Cellular Antiviral Strategy. Cell 2018; 175:1728-1729. [PMID: 30550784 DOI: 10.1016/j.cell.2018.11.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Viruses use mimicry to hijack cellular machinery, but can human cells use mimicry as an antiviral approach? Batra et al. identify a novel antiviral restriction factor, RBBP6, by characterizing the cellular interactome of Ebola virus. RBBP6 targets the Ebola virus transcription factor VP30 by mimicking the binding of Ebola virus nucleoprotein.
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Affiliation(s)
- Nicholas C Wu
- Department of Integrative Structural and Computational Biology, the Scripps Research Institute, La Jolla, CA 92037, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, the Scripps Research Institute, La Jolla, CA 92037, USA.
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31
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Batra J, Hultquist JF, Liu D, Shtanko O, Von Dollen J, Satkamp L, Jang GM, Luthra P, Schwarz TM, Small GI, Arnett E, Anantpadma M, Reyes A, Leung DW, Kaake R, Haas P, Schmidt CB, Schlesinger LS, LaCount DJ, Davey RA, Amarasinghe GK, Basler CF, Krogan NJ. Protein Interaction Mapping Identifies RBBP6 as a Negative Regulator of Ebola Virus Replication. Cell 2018; 175:1917-1930.e13. [PMID: 30550789 PMCID: PMC6366944 DOI: 10.1016/j.cell.2018.08.044] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 05/17/2018] [Accepted: 08/17/2018] [Indexed: 01/21/2023]
Abstract
Ebola virus (EBOV) infection often results in fatal illness in humans, yet little is known about how EBOV usurps host pathways during infection. To address this, we used affinity tag-purification mass spectrometry (AP-MS) to generate an EBOV-host protein-protein interaction (PPI) map. We uncovered 194 high-confidence EBOV-human PPIs, including one between the viral transcription regulator VP30 and the host ubiquitin ligase RBBP6. Domain mapping identified a 23 amino acid region within RBBP6 that binds to VP30. A crystal structure of the VP30-RBBP6 peptide complex revealed that RBBP6 mimics the viral nucleoprotein (NP) binding to the same interface of VP30. Knockdown of endogenous RBBP6 stimulated viral transcription and increased EBOV replication, whereas overexpression of either RBBP6 or the peptide strongly inhibited both. These results demonstrate the therapeutic potential of biologics that target this interface and identify additional PPIs that may be leveraged for novel therapeutic strategies.
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Affiliation(s)
- Jyoti Batra
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Judd F Hultquist
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA; Division of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Dandan Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63105, USA
| | - Olena Shtanko
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, TX 78245, USA
| | - John Von Dollen
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Laura Satkamp
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Gwendolyn M Jang
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Priya Luthra
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Toni M Schwarz
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Gabriel I Small
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63105, USA
| | - Eusondia Arnett
- Texas Biomedical Research Institute, San Antonio, TX 78245, USA
| | - Manu Anantpadma
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, TX 78245, USA
| | - Ann Reyes
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, TX 78245, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63105, USA
| | - Robyn Kaake
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Paige Haas
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Carson B Schmidt
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | | | - Douglas J LaCount
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
| | - Robert A Davey
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, TX 78245, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63105, USA
| | - Christopher F Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA.
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA.
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32
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Basler CF, Krogan NJ, Leung DW, Amarasinghe GK. Virus and host interactions critical for filoviral RNA synthesis as therapeutic targets. Antiviral Res 2018; 162:90-100. [PMID: 30550800 DOI: 10.1016/j.antiviral.2018.12.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/05/2018] [Accepted: 12/08/2018] [Indexed: 01/24/2023]
Abstract
Filoviruses, which include Ebola virus (EBOV) and Marburg virus, are negative-sense RNA viruses associated with sporadic outbreaks of severe viral hemorrhagic fever characterized by uncontrolled virus replication. The extreme virulence and emerging nature of these zoonotic pathogens make them a significant threat to human health. Replication of the filovirus genome and production of viral RNAs require the function of a complex of four viral proteins, the nucleoprotein (NP), viral protein 35 (VP35), viral protein 30 (VP30) and large protein (L). The latter performs the enzymatic activities required for production of viral RNAs and capping of viral mRNAs. Although it has been recognized that interactions between the virus-encoded components of the EBOV RNA polymerase complex are required for viral RNA synthesis reactions, specific molecular details have, until recently, been lacking. New efforts have combined structural biology and molecular virology to reveal in great detail the molecular basis for critical protein-protein interactions (PPIs) necessary for viral RNA synthesis. These efforts include recent studies that have identified a range of interacting host factors and in some instances demonstrated unique mechanisms by which they act. For a select number of these interactions, combined use of mutagenesis, over-expressing of peptides corresponding to PPI interfaces and identification of small molecules that disrupt PPIs have demonstrated the functional significance of virus-virus and virus-host PPIs and suggest several as potential targets for therapeutic intervention.
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Affiliation(s)
- Christopher F Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA.
| | - Nevan J Krogan
- Quantitative Biosciences Institute (QBI), UCSF, San Francisco, CA, USA; Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Olson MA. Conformational Selection of a Polyproline Peptide by Ebola Virus VP30. Proteomics 2018; 18:e1800081. [PMID: 30302912 DOI: 10.1002/pmic.201800081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 09/18/2018] [Indexed: 11/09/2022]
Abstract
An adaptive temperature-based replica-exchange simulation of a peptide extracted from the Ebola virus nucleoprotein containing a polyproline sequence motif is reported. The simulation results of applying the CHARMM36m force field with a generalized Born solvent model is presented. Conformational heterogeneity is described by potentials of mean force (PMFs) for a set of reaction coordinates that define the topological fold space. Starting from an extended backbone conformation of the peptide observed in an X-ray crystallographic assembly with the Ebola virus protein VP30, the PMFs report a conformational landscape populated by chain excursions to collapsed states with limited transitions to either an extended fold or a canonical polyproline type II helix. Clustering of the conformations and applying an elastic network interpolation model yield a multistep pathway of conformational selection that minimizes the net transition-state cost from the population hub to the bound state. Related difference between the pathway endpoints taken from the PMFs reveal a significant free-energy penalty in reaching a population shift. To evaluate sequence fitness of the Ebola virus peptide in generating probability distributions, two human sequence variants are modeled and are found to produce profiles that show extensive deviations, thus suggesting either dissimilar binding mechanisms or the lack of recognition by VP30.
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Affiliation(s)
- Mark A Olson
- Department of Cell Biology and Biochemistry, Molecular and Translational Sciences Division, USAMRIID, Frederick, MD, 21702, USA
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34
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Su Z, Wu C, Shi L, Luthra P, Pintilie GD, Johnson B, Porter JR, Ge P, Chen M, Liu G, Frederick TE, Binning JM, Bowman GR, Zhou ZH, Basler CF, Gross ML, Leung DW, Chiu W, Amarasinghe GK. Electron Cryo-microscopy Structure of Ebola Virus Nucleoprotein Reveals a Mechanism for Nucleocapsid-like Assembly. Cell 2018; 172:966-978.e12. [PMID: 29474922 PMCID: PMC5973842 DOI: 10.1016/j.cell.2018.02.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 12/27/2017] [Accepted: 01/31/2018] [Indexed: 01/24/2023]
Abstract
Ebola virus nucleoprotein (eNP) assembles into higher-ordered structures that form the viral nucleocapsid (NC) and serve as the scaffold for viral RNA synthesis. However, molecular insights into the NC assembly process are lacking. Using a hybrid approach, we characterized the NC-like assembly of eNP, identified novel regulatory elements, and described how these elements impact function. We generated a three-dimensional structure of the eNP NC-like assembly at 5.8 Å using electron cryo-microscopy and identified a new regulatory role for eNP helices α22-α23. Biochemical, biophysical, and mutational analyses revealed that inter-eNP contacts within α22-α23 are critical for viral NC assembly and regulate viral RNA synthesis. These observations suggest that the N terminus and α22-α23 of eNP function as context-dependent regulatory modules (CDRMs). Our current study provides a framework for a structural mechanism for NC-like assembly and a new therapeutic target.
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Affiliation(s)
- Zhaoming Su
- Department of Bioengineering and Department of Microbiology and Immunology, James H. Clark Center, Stanford University, Stanford, CA 94305, USA
| | - Chao Wu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Liuqing Shi
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Priya Luthra
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Grigore D Pintilie
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Britney Johnson
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Justin R Porter
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Peng Ge
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Muyuan Chen
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Gai Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Thomas E Frederick
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jennifer M Binning
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gregory R Bowman
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Z Hong Zhou
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Christopher F Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Wah Chiu
- Department of Bioengineering and Department of Microbiology and Immunology, James H. Clark Center, Stanford University, Stanford, CA 94305, USA.
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Kruse T, Biedenkopf N, Hertz EPT, Dietzel E, Stalmann G, López-Méndez B, Davey NE, Nilsson J, Becker S. The Ebola Virus Nucleoprotein Recruits the Host PP2A-B56 Phosphatase to Activate Transcriptional Support Activity of VP30. Mol Cell 2017; 69:136-145.e6. [PMID: 29290611 DOI: 10.1016/j.molcel.2017.11.034] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/01/2017] [Accepted: 11/27/2017] [Indexed: 10/18/2022]
Abstract
Transcription of the Ebola virus genome depends on the viral transcription factor VP30 in its unphosphorylated form, but the underlying molecular mechanism of VP30 dephosphorylation is unknown. Here we show that the Ebola virus nucleoprotein (NP) recruits the host PP2A-B56 protein phosphatase through a B56-binding LxxIxE motif and that this motif is essential for VP30 dephosphorylation and viral transcription. The LxxIxE motif and the binding site of VP30 in NP are in close proximity, and both binding sites are required for the dephosphorylation of VP30. We generate a specific inhibitor of PP2A-B56 and show that it suppresses Ebola virus transcription and infection. This work dissects the molecular mechanism of VP30 dephosphorylation by PP2A-B56, and it pinpoints this phosphatase as a potential target for therapeutic intervention.
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Affiliation(s)
- Thomas Kruse
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Nadine Biedenkopf
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany
| | - Emil Peter Thrane Hertz
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Erik Dietzel
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany
| | - Gertrud Stalmann
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany
| | - Blanca López-Méndez
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Norman E Davey
- Conway Institute of Biomolecular and Biomedical Sciences, University College Dublin, Dublin 4, Ireland
| | - Jakob Nilsson
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark.
| | - Stephan Becker
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany.
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36
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Development of small-molecule viral inhibitors targeting various stages of the life cycle of emerging and re-emerging viruses. Front Med 2017; 11:449-461. [PMID: 29170916 PMCID: PMC7089273 DOI: 10.1007/s11684-017-0589-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/22/2017] [Indexed: 01/22/2023]
Abstract
In recent years, unexpected outbreaks of infectious diseases caused by emerging and re-emerging viruses have become more frequent, which is possibly due to environmental changes. These outbreaks result in the loss of life and economic hardship. Vaccines and therapeutics should be developed for the prevention and treatment of infectious diseases. In this review, we summarize and discuss the latest progress in the development of small-molecule viral inhibitors against highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus, Ebola virus, and Zika virus. These viruses can interfere with the specific steps of viral life cycle by blocking the binding between virus and host cells, disrupting viral endocytosis, disturbing membrane fusion, and interrupting viral RNA replication and translation, thereby demonstrating potent therapeutic effect against various emerging and re-emerging viruses. We also discuss some general strategies for developing small-molecule viral inhibitors.
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