1
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Lawler JL, Terrell S, Coen DM. The conserved RNP motif of the herpes simplex virus 1 family B DNA polymerase is crucial for viral DNA synthesis but not polymerase activity. Virology 2024; 594:110035. [PMID: 38554655 DOI: 10.1016/j.virol.2024.110035] [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: 01/08/2024] [Revised: 02/08/2024] [Accepted: 02/21/2024] [Indexed: 04/02/2024]
Abstract
The herpes simplex virus 1 DNA polymerase contains a highly conserved structural motif found in most family B polymerases and certain RNA-binding proteins. To investigate its importance within cells, we constructed a mutant virus with substitutions in two residues of the motif and a rescued derivative. The substitutions resulted in severe impairment of plaque formation, yields of infectious virus, and viral DNA synthesis while not meaningfully affecting expression of the mutant enzyme, its co-localization with the viral single-stranded DNA binding protein at intranuclear punctate sites in non-complementing cells or in replication compartments in complementing cells, or viral DNA polymerase activity. Taken together, our results indicate that the RNA binding motif plays a crucial role in herpes simplex virus 1 DNA synthesis through a mechanism separate from effects on polymerase activity, thus identifying a distinct essential function of this motif with implications for hypotheses regarding its biochemical functions.
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Affiliation(s)
- Jessica L Lawler
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA; Committee on Virology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
| | - Shariya Terrell
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
| | - Donald M Coen
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA; Committee on Virology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
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2
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Krasnov VP, Andronova VL, Belyavsky AV, Borisevich SS, Galegov GA, Kandarakov OF, Gruzdev DA, Vozdvizhenskaya OA, Levit GL. Large Subunit of the Human Herpes Simplex Virus Terminase as a Promising Target in Design of Anti-Herpesvirus Agents. Molecules 2023; 28:7375. [PMID: 37959793 PMCID: PMC10649544 DOI: 10.3390/molecules28217375] [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: 09/13/2023] [Revised: 10/19/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023] Open
Abstract
Herpes simplex virus type 1 (HSV-1) is an extremely widespread pathogen characterized by recurrent infections. HSV-1 most commonly causes painful blisters or sores around the mouth or on the genitals, but it can also cause keratitis or, rarely, encephalitis. First-line and second-line antiviral drugs used to treat HSV infections, acyclovir and related compounds, as well as foscarnet and cidofovir, selectively inhibit herpesvirus DNA polymerase (DNA-pol). It has been previously found that (S)-4-[6-(purin-6-yl)aminohexanoyl]-7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine (compound 1) exhibits selective anti-herpesvirus activity against HSV-1 in cell culture, including acyclovir-resistant mutants, so we consider it as a lead compound. In this work, the selection of HSV-1 clones resistant to the lead compound was carried out. High-throughput sequencing of resistant clones and reference HSV-1/L2 parent strain was performed to identify the genetic determinants of the virus's resistance to the lead compound. We identified a candidate mutation presumably associated with resistance to the virus, namely the T321I mutation in the UL15 gene encoding the large terminase subunit. Molecular modeling was used to evaluate the affinity and dynamics of the lead compound binding to the putative terminase binding site. The results obtained suggest that the lead compound, by binding to pUL15, affects the terminase complex. pUL15, which is directly involved in the processing and packaging of viral DNA, is one of the crucial components of the HSV terminase complex. The loss of its functional activity leads to disruption of the formation of mature virions, so it represents a promising drug target. The discovery of anti-herpesvirus agents that affect biotargets other than DNA polymerase will expand our possibilities of targeting HSV infections, including those resistant to baseline drugs.
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Affiliation(s)
- Victor P. Krasnov
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
| | - Valeriya L. Andronova
- Gamaleya National Research Center for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, Moscow 123098, Russia; (V.L.A.); (G.A.G.)
| | - Alexander V. Belyavsky
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia; (A.V.B.); (O.F.K.)
| | | | - George A. Galegov
- Gamaleya National Research Center for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, Moscow 123098, Russia; (V.L.A.); (G.A.G.)
| | - Oleg F. Kandarakov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia; (A.V.B.); (O.F.K.)
| | - Dmitry A. Gruzdev
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
| | - Olga A. Vozdvizhenskaya
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
| | - Galina L. Levit
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
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3
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Smith KR, Paul S, Dong Q, Anannya O, Oldenburg DG, Forrest JC, McBride KM, Krug LT. Uracil-DNA glycosylase of murine gammaherpesvirus 68 binds cognate viral replication factors independently of its catalytic residues. mSphere 2023; 8:e0027823. [PMID: 37747202 PMCID: PMC10597349 DOI: 10.1128/msphere.00278-23] [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: 05/19/2023] [Accepted: 08/03/2023] [Indexed: 09/26/2023] Open
Abstract
Herpesviruses are large double-stranded DNA viruses that encode core replication proteins and accessory factors involved in nucleotide metabolism and DNA repair. Mammalian uracil-DNA glycosylases (UNG) excise deleterious uracil residues from their genomic DNA. Each herpesvirus UNG studied to date has demonstrated conservation of the enzymatic function to excise uracil residues from DNA. We previously reported that a murine gammaherpesvirus (MHV68) with a stop codon in ORF46 (ORF46.stop) that encodes for vUNG was defective in lytic replication and latency in vivo. However, a mutant virus that expressed a catalytically inactive vUNG (ORF46.CM) had no replication defect unless coupled with additional mutations in the catalytic motif of the viral dUTPase (ORF54.CM). The disparate phenotypes observed in the vUNG mutants led us to explore the non-enzymatic properties of vUNG. Immunoprecipitation of vUNG followed by mass spectrometry in MHV68-infected fibroblasts identified a complex comprising the cognate viral DNA polymerase, vPOL, encoded by ORF9, and the viral DNA polymerase processivity factor, vPPF, encoded by ORF59. MHV68 vUNG co-localized with vPOL and vPPF in subnuclear structures consistent with viral replication compartments. In reciprocal co-immunoprecipitations, the vUNG formed a complex with the vPOL and vPPF upon transfection with either factor alone or in combination. Lastly, we determined that key catalytic residues of vUNG are not required for interactions with vPOL and vPPF upon transfection or in the context of infection. We conclude that the vUNG of MHV68 associates with vPOL and vPPF independently of its catalytic activity. IMPORTANCE Gammaherpesviruses encode a uracil-DNA glycosylase (vUNG) that is presumed to excise uracil residues from viral genomes. We previously identified the vUNG enzymatic activity, but not the protein itself, as dispensable for gammaherpesvirus replication in vivo. In this study, we report a non-enzymatic role for the viral UNG of a murine gammaherpesvirus in forming a complex with two key components of the viral DNA replication machinery. Understanding the role of the vUNG in this viral DNA replication complex may inform the development of antiviral drugs that combat gammaherpesvirus-associated cancers.
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Affiliation(s)
- Kyle R. Smith
- HIV and AIDS Malignancy Branch, National Cancer Institute, Bethesda, Maryland, USA
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Somnath Paul
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Qiwen Dong
- Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, New York, USA
| | - Orchi Anannya
- Department of Physiology and Biophysics, Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, New York, USA
| | - Darby G. Oldenburg
- Gundersen Medical Foundation, Gunderson Health System, La Crosse, Wisconsin, USA
| | - J. Craig Forrest
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Kevin M. McBride
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Laurie T. Krug
- HIV and AIDS Malignancy Branch, National Cancer Institute, Bethesda, Maryland, USA
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
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4
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Sterrenberg VT, Stalling D, Knaack JIH, Soh TK, Bosse JB, Meier C. A TriPPPro-Nucleotide Reporter with Optimized Cell-Permeable Dyes for Metabolic Labeling of Cellular and Viral DNA in Living Cells. Angew Chem Int Ed Engl 2023; 62:e202308271. [PMID: 37435767 DOI: 10.1002/anie.202308271] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/04/2023] [Accepted: 07/07/2023] [Indexed: 07/13/2023]
Abstract
The metabolic labeling of nucleic acids in living cells is highly desirable to track the dynamics of nucleic acid metabolism in real-time and has the potential to provide novel insights into cellular biology as well as pathogen-host interactions. Catalyst-free inverse electron demand Diels-Alder reactions (iEDDA) with nucleosides carrying highly reactive moieties such as axial 2-trans-cyclooctene (2TCOa) would be an ideal tool to allow intracellular labeling of DNA. However, cellular kinase phosphorylation of the modified nucleosides is needed after cellular uptake as triphosphates are not membrane permeable. Unfortunately, the narrow substrate window of most endogenous kinases limits the use of highly reactive moieties. Here, we apply our TriPPPro (triphosphate pronucleotide) approach to directly deliver a highly reactive 2TCOa-modified 2'-deoxycytidine triphosphate reporter into living cells. We show that this nucleoside triphosphate is metabolically incorporated into de novo synthesized cellular and viral DNA and can be labeled with highly reactive and cell-permeable fluorescent dye-tetrazine conjugates via iEDDA to visualize DNA in living cells directly. Thus, we present the first comprehensive method for live-cell imaging of cellular and viral nucleic acids using a two-step labeling approach.
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Affiliation(s)
- Vincente T Sterrenberg
- Department of Chemistry, Faculty of Sciences, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
| | - Dörte Stalling
- CSSB Centre for Structural Systems Biology, Notkestraße 85, Building 15, 22607, Hamburg, Germany
- Institute of Virology, Hannover Medical School (MHH), 30625, Hannover, Germany
- Leibniz Institute of Virology (LIV), 20251, Hamburg, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, 30625, Hannover, Germany
| | - J Iven H Knaack
- Department of Chemistry, Faculty of Sciences, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
| | - Timothy K Soh
- CSSB Centre for Structural Systems Biology, Notkestraße 85, Building 15, 22607, Hamburg, Germany
- Institute of Virology, Hannover Medical School (MHH), 30625, Hannover, Germany
- Leibniz Institute of Virology (LIV), 20251, Hamburg, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, 30625, Hannover, Germany
| | - Jens B Bosse
- CSSB Centre for Structural Systems Biology, Notkestraße 85, Building 15, 22607, Hamburg, Germany
- Institute of Virology, Hannover Medical School (MHH), 30625, Hannover, Germany
- Leibniz Institute of Virology (LIV), 20251, Hamburg, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, 30625, Hannover, Germany
| | - Chris Meier
- Department of Chemistry, Faculty of Sciences, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
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5
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Lad SB, Upadhyay M, Thorat P, Nair D, Moseley GW, Srivastava S, Pradeepkumar PI, Kondabagil K. Biochemical Reconstitution of the Mimiviral Base Excision Repair Pathway. J Mol Biol 2023; 435:168188. [PMID: 37380013 DOI: 10.1016/j.jmb.2023.168188] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 06/14/2023] [Accepted: 06/20/2023] [Indexed: 06/30/2023]
Abstract
Viruses are believed to be the obligate intracellular parasites that only carry genes essential for infecting and hijacking the host cell machinery. However, a recently discovered group of viruses belonging to the phylum nucleocytovirocota, also known as the nucleo-cytoplasmic large DNA viruses (NCLDVs), possess a number of genes that code for proteins predicted to be involved in metabolism, and DNA replication, and repair. In the present study, first, using proteomics of viral particles, we show that several proteins required for the completion of the DNA base excision repair (BER) pathway are packaged within the virions of Mimivirus as well as related viruses while they are absent from the virions of Marseillevirus and Kurlavirus that are NCLDVs with smaller genomes. We have thoroughly characterized three putative base excision repair enzymes from Mimivirus, a prototype NCLDV and successfully reconstituted the BER pathway using the purified recombinant proteins. The mimiviral uracil-DNA glycosylase (mvUDG) excises uracil from both ssDNA and dsDNA, a novel finding contrary to earlier studies. The putative AP-endonuclease (mvAPE) specifically cleaves at the abasic site created by the glycosylase while also exhibiting the 3'-5' exonuclease activity. The Mimivirus polymerase X protein (mvPolX) can bind to gapped DNA substrates and perform single nucleotide gap-filling followed by downstream strand displacement. Furthermore, we show that when reconstituted in vitro, mvUDG, mvAPE, and mvPolX function cohesively to repair a uracil-containing DNA predominantly by long patch BER and together, may participate in the BER pathway during the early phase of Mimivirus life-cycle.
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Affiliation(s)
- Shailesh B Lad
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India. https://twitter.com/shailesh2603
| | - Monica Upadhyay
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India; Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia. https://twitter.com/upadhyaymonica
| | - Pracheta Thorat
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India
| | - Divya Nair
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India
| | - Gregory W Moseley
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia
| | - Sanjeeva Srivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India. https://twitter.com/sanjeeva_IITB
| | - P I Pradeepkumar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India. https://twitter.com/pradeepkumarpi
| | - Kiran Kondabagil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India.
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6
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Mu Y, Zelazowska MA, Chen Z, Plummer JB, Dong Q, Krug LT, McBride KM. Divergent structures of Mammalian and gammaherpesvirus uracil DNA glycosylases confer distinct DNA binding and substrate activity. DNA Repair (Amst) 2023; 128:103515. [PMID: 37315375 PMCID: PMC10441670 DOI: 10.1016/j.dnarep.2023.103515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 05/21/2023] [Accepted: 05/30/2023] [Indexed: 06/16/2023]
Abstract
Uracil DNA glycosylase (UNG) removes mutagenic uracil base from DNA to initiate base excision repair (BER). The result is an abasic site (AP site) that is further processed by the high-fidelity BER pathway to complete repair and maintain genome integrity. The gammaherpesviruses (GHVs), human Kaposi sarcoma herpesvirus (KSHV), Epstein-Barr virus (EBV), and murine gammaherpesvirus 68 (MHV68) encode functional UNGs that have a role in viral genome replication. Mammalian and GHVs UNG share overall structure and sequence similarity except for a divergent amino-terminal domain and a leucine loop motif in the DNA binding domain that varies in sequence and length. To determine if divergent domains contribute to functional differences between GHV and mammalian UNGs, we analyzed their roles in DNA interaction and catalysis. By utilizing chimeric UNGs with swapped domains we found that the leucine loop in GHV, but not mammalian UNGs facilitates interaction with AP sites and that the amino-terminal domain modulates this interaction. We also found that the leucine loop structure contributes to differential UDGase activity on uracil in single- versus double-stranded DNA. Taken together we demonstrate that the GHV UNGs evolved divergent domains from their mammalian counterparts that contribute to differential biochemical properties from their mammalian counterparts.
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Affiliation(s)
- Yunxiang Mu
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Monika A Zelazowska
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Zaowen Chen
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Joshua B Plummer
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Qiwen Dong
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794, USA; Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, NY 11794, USA
| | - Laurie T Krug
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794, USA; HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kevin M McBride
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA.
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7
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Smith KR, Paul S, Dong Q, Anannya O, Oldenburg DG, Forrest JC, McBride KM, Krug LT. Uracil-DNA Glycosylase of Murine Gammaherpesvirus 68 Binds Cognate Viral Replication Factors Independently of its Catalytic Residues. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.19.541466. [PMID: 37398059 PMCID: PMC10312458 DOI: 10.1101/2023.05.19.541466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Herpesviruses are large double-stranded DNA viruses that encode core replication proteins and accessory factors involved in nucleotide metabolism and DNA repair. Mammalian Uracil-DNA glycosylases (UNG) excise deleterious uracil residues from their genomic DNA. Each herpesvirus UNG studied to date has demonstrated conservation of the enzymatic function to excise uracil residues from DNA. We previously reported that a murine gammaherpesvirus (MHV68) with a stop codon in ORF46 (ORF46.stop) that encodes for vUNG was defective in lytic replication and latency in vivo. However, a mutant virus that expressed a catalytically inactive vUNG (ORF46.CM) had no replication defect, unless coupled with additional mutations in the catalytic motif of the viral dUTPase (ORF54.CM). The disparate phenotypes observed in the vUNG mutants led us to explore the non-enzymatic properties of vUNG. Immunoprecipitation of vUNG followed by mass spectrometry in MHV68-infected fibroblasts identified a complex comprised of the cognate viral DNA polymerase, vPOL encoded by ORF9 , and the viral DNA polymerase processivity factor, vPPF encoded by ORF59 . MHV68 vUNG colocalized with vPOL and vPPF in subnuclear structures consistent with viral replication compartments. In reciprocal co-immunoprecipitations, the vUNG formed a complex with the vPOL and vPPF upon transfection with either factor alone, or in combination. Last, we determined that key catalytic residues of vUNG are not required for interactions with vPOL and vPPF upon transfection or in the context of infection. We conclude that the vUNG of MHV68 associates with vPOL and vPPF independently of its catalytic activity. IMPORTANCE Gammaherpesviruses encode a uracil-DNA glycosylase (vUNG) that is presumed to excise uracil residues from viral genomes. We previously identified the vUNG enzymatic activity, but not the protein itself, as dispensable for gammaherpesvirus replication in vivo . In this study, we report a non-enzymatic role for the viral UNG of a murine gammaherpesvirus to form a complex with two key components of the viral DNA replication machinery. Understanding the role of the vUNG in this viral DNA replication complex may inform the development of antiviral drugs that combat gammaherpesvirus associated cancers.
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Affiliation(s)
- Kyle R. Smith
- HIV and AIDS Malignancy Branch, National Cancer Institute, Bethesda, MD, USA
- Department of Microbiology & Immunology, Stony Brook University, Stony Brook, NY, USA
| | - Somnath Paul
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Qiwen Dong
- Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, NY, USA
| | - Orchi Anannya
- Department of Physiology and Biophysics, Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, NY, USA
| | - Darby G. Oldenburg
- Gundersen Medical Foundation, Gunderson Health System, LaCrosse, Wisconsin, USA
| | - J. Craig Forrest
- Department of Microbiology & Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Kevin M. McBride
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Laurie T. Krug
- HIV and AIDS Malignancy Branch, National Cancer Institute, Bethesda, MD, USA
- Department of Microbiology & Immunology, Stony Brook University, Stony Brook, NY, USA
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8
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Abstract
Herpesviruses comprise a family of DNA viruses that cause a variety of human and veterinary diseases. During productive infection, mammalian, avian, and reptilian herpesviruses replicate their genomes using a set of conserved viral proteins that include a two subunit DNA polymerase. This enzyme is both a model system for family B DNA polymerases and a target for inhibition by antiviral drugs. This chapter reviews the structure, function, and mechanisms of the polymerase of herpes simplex viruses 1 and 2 (HSV), with only occasional mention of polymerases of other herpesviruses such as human cytomegalovirus (HCMV). Antiviral polymerase inhibitors have had the most success against HSV and HCMV. Detailed structural information regarding HSV DNA polymerase is available, as is much functional information regarding the activities of the catalytic subunit (Pol), which include a DNA polymerization activity that can utilize both DNA and RNA primers, a 3'-5' exonuclease activity, and other activities in DNA synthesis and repair and in pathogenesis, including some remaining to be biochemically defined. Similarly, much is known regarding the accessory subunit, which both resembles and differs from sliding clamp processivity factors such as PCNA, and the interactions of this subunit with Pol and DNA. Both subunits contribute to replication fidelity (or lack thereof). The availability of both pharmacologic and genetic tools not only enabled the initial identification of Pol and the pol gene, but has also helped dissect their functions. Nevertheless, important questions remain for this long-studied enzyme, which is still an attractive target for new drug discovery.
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9
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Donohoe O, Zhang H, Delrez N, Gao Y, Suárez NM, Davison AJ, Vanderplasschen A. Genomes of Anguillid Herpesvirus 1 Strains Reveal Evolutionary Disparities and Low Genetic Diversity in the Genus Cyprinivirus. Microorganisms 2021; 9:microorganisms9050998. [PMID: 34063135 PMCID: PMC8148134 DOI: 10.3390/microorganisms9050998] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 12/24/2022] Open
Abstract
Anguillid herpesvirus 1 (AngHV-1) is a pathogen of eels and a member of the genus Cyprinivirus in the family Alloherpesviridae. We have compared the biological and genomic features of different AngHV-1 strains, focusing on their growth kinetics in vitro and genetic content, diversity, and recombination. Comparisons based on three core genes conserved among alloherpesviruses revealed that AngHV-1 exhibits a slower rate of change and less positive selection than other cypriniviruses. We propose that this may be linked to major differences in host species and corresponding epidemiological circumstances. Efforts to derive evolutionary rate estimates for cypriniviruses under various theoretical models were ultimately unrewarding. We highlight the potential value of future collaborative efforts towards generating short-term evolutionary rate estimates based on known sequence sampling dates. Finally, we revealed that there is significantly less genetic diversity in core gene sequences within cyprinivirus species clades compared to species in the family Herpesviridae. This suggests that cyprinivirus species may have undergone much more vigorous purifying selection post species clade divergence. We discuss whether this may be linked to biological and anthropogenic factors or to sampling bias, and we propose that the comparison of short-term evolutionary rates between species may provide further insights into these differences.
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Affiliation(s)
- Owen Donohoe
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium; (O.D.); (H.Z.); (N.D.); (Y.G.)
- Bioscience Research Institute, Athlone Institute of Technology, Athlone, Co. N37 HD68 Westmeath, Ireland
| | - Haiyan Zhang
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium; (O.D.); (H.Z.); (N.D.); (Y.G.)
| | - Natacha Delrez
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium; (O.D.); (H.Z.); (N.D.); (Y.G.)
| | - Yuan Gao
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium; (O.D.); (H.Z.); (N.D.); (Y.G.)
| | - Nicolás M. Suárez
- MRC-Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK; (N.M.S.); (A.J.D.)
| | - Andrew J. Davison
- MRC-Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK; (N.M.S.); (A.J.D.)
| | - Alain Vanderplasschen
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium; (O.D.); (H.Z.); (N.D.); (Y.G.)
- Correspondence: ; Tel.: +32-4-366-42-64; Fax: +32-4-366-42-61
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10
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Li M, Xu Z, Zou X, Wang Y, Li Y, Ou X, Deng Y, Guo Y, Gan W, Chen D, Peng T, Xiao J, Cai M. Intracellular distribution of pseudorabies virus UL2 and detection of its nuclear import mechanism. Biol Chem 2021; 401:309-317. [PMID: 31665103 DOI: 10.1515/hsz-2019-0311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 10/10/2019] [Indexed: 11/15/2022]
Abstract
Pseudorabies virus (PRV) UL2 (pUL2) is a multifunctional protein, which is homologous with herpes simplex virus 1 early protein UL2 (hUL2) and crucial for the viral propagation. Yet, how pUL2 executes its roles in the viral life cycle remain inadequately understood. In order to uncover its effect on the procedure of PRV infection, investigation was performed to examine the subcellular distribution of pUL2 and establish its trafficking mechanism. In the present study, enhanced yellow fluorescent protein or Myc tag fused pUL2 was transiently overexpressed in transfected cells and exhibited an absolutely nuclear accumulation without the existence of other PRV proteins. Additionally, the nuclear trafficking of pUL2 was proved to rely on Ran-, transportin-1, importin β1, importin α1, α3 and α5. Accordingly, these data will benefit the knowledge of pUL2-mediated biological effects in PRV infection cycle.
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Affiliation(s)
- Meili Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Zuo Xu
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Xingmei Zou
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Yuanfang Wang
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Yiwen Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Xiaowen Ou
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Yangxi Deng
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Yingjie Guo
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Weidong Gan
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Daixiong Chen
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
| | - Tao Peng
- State Key Laboratory of Respiratory Diseases, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Xinzao Town, Panyu, Guangzhou 511436, Guangdong, China.,South China Vaccine Corporation Limited, Guangzhou Science Park, Guangzhou 510663, Guangdong, China
| | - Jing Xiao
- State Key Laboratory of Respiratory Diseases, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Xinzao Town, Panyu, Guangzhou 511436, Guangdong, China
| | - Mingsheng Cai
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong, China.,Department of Pathogenic Biology and Immunology, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, No. 250 Changgang Dong Road, Haizhu District, Guangzhou 510260, Guangdong, China
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11
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Gou H, Bian Z, Li Y, Cai R, Jiang Z, Song S, Zhang K, Chu P, Yang D, Li C. Metabolomics Exploration of Pseudorabies Virus Reprogramming Metabolic Profiles of PK-15 Cells to Enhance Viral Replication. Front Cell Infect Microbiol 2021; 10:599087. [PMID: 33585273 PMCID: PMC7879706 DOI: 10.3389/fcimb.2020.599087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 12/14/2020] [Indexed: 12/23/2022] Open
Abstract
For viral replication to occur in host cells, low-molecular-weight metabolites are necessary for virion assembly. Recently, metabolomics has shown great promise in uncovering the highly complex mechanisms associated with virus-host interactions. In this study, the metabolic networks in PK-15 cells infected with a variant virulent or classical attenuated pseudorabies virus (PRV) strains were explored using gas chromatography-mass spectrometry (GC-MS) analysis. Although total numbers of metabolites whose levels were altered by infection with the variant virulent strain or the classical attenuated strain were different at 8 and 16 h post infection (hpi), the predicted levels of differential metabolic components were shown to be associated with specific pathways, including glycolysis as well as amino acid and nucleotide metabolism. The glucose depletion and glycolysis inhibitors 2DG and oxamate could reduce the level of PRV replication in PK-15 cells. In addition, the inhibition of the pentose phosphate pathway (PPP) resulted in an obvious decline of viral titers, but the prevention of oxidative phosphorylation in the tricarboxylic acid (TCA) cycle had a minimal effect on viral replication. Glutamine starvation resulted in the decline of viral titers, which could be restored by supplemental addition in the culture media. However, inhibition of glutaminase (GLS) activity or the supplement of 2-ketoglutarate into glutamine-deleted DMEM did not alter PRV replication in PK-15 cells. The results of the current study indicate that PRV reprograms the metabolic activities of PK-15 cells. The metabolic flux from glycolysis, PPP and glutamine metabolism to nucleotide biosynthesis was essential for PRV to enhance its replication. This study will help to identify the biochemical materials utilized by PRV replication in host cells, and this knowledge can aid in developing new antiviral strategies.
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Affiliation(s)
- Hongchao Gou
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Zhibiao Bian
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Yan Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Rujian Cai
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Zhiyong Jiang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Shuai Song
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Kunli Zhang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Pinpin Chu
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Dongxia Yang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Chunling Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.,Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China.,Guangdong Open Laboratory of Veterinary Public Health, Guangzhou, China.,Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
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12
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Dogrammatzis C, Waisner H, Kalamvoki M. "Non-Essential" Proteins of HSV-1 with Essential Roles In Vivo: A Comprehensive Review. Viruses 2020; 13:E17. [PMID: 33374862 PMCID: PMC7824580 DOI: 10.3390/v13010017] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/17/2020] [Accepted: 12/18/2020] [Indexed: 12/19/2022] Open
Abstract
Viruses encode for structural proteins that participate in virion formation and include capsid and envelope proteins. In addition, viruses encode for an array of non-structural accessory proteins important for replication, spread, and immune evasion in the host and are often linked to virus pathogenesis. Most virus accessory proteins are non-essential for growth in cell culture because of the simplicity of the infection barriers or because they have roles only during a state of the infection that does not exist in cell cultures (i.e., tissue-specific functions), or finally because host factors in cell culture can complement their absence. For these reasons, the study of most nonessential viral factors is more complex and requires development of suitable cell culture systems and in vivo models. Approximately half of the proteins encoded by the herpes simplex virus 1 (HSV-1) genome have been classified as non-essential. These proteins have essential roles in vivo in counteracting antiviral responses, facilitating the spread of the virus from the sites of initial infection to the peripheral nervous system, where it establishes lifelong reservoirs, virus pathogenesis, and other regulatory roles during infection. Understanding the functions of the non-essential proteins of herpesviruses is important to understand mechanisms of viral pathogenesis but also to harness properties of these viruses for therapeutic purposes. Here, we have provided a comprehensive summary of the functions of HSV-1 non-essential proteins.
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Affiliation(s)
| | | | - Maria Kalamvoki
- Department of Microbiology, Molecular Genetics, and Immunology, University of Kansas Medical Center, Kansas City, KS 66160, USA; (C.D.); (H.W.)
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13
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Cai M, Liao Z, Zou X, Xu Z, Wang Y, Li T, Li Y, Ou X, Deng Y, Guo Y, Peng T, Li M. Herpes Simplex Virus 1 UL2 Inhibits the TNF-α-Mediated NF-κB Activity by Interacting With p65/p50. Front Immunol 2020; 11:549. [PMID: 32477319 PMCID: PMC7237644 DOI: 10.3389/fimmu.2020.00549] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 03/10/2020] [Indexed: 12/31/2022] Open
Abstract
Herpes simplex virus 1 (HSV-1) is a large double-stranded DNA virus that encodes at least 80 viral proteins, many of which are involved in the virus-host interaction and are beneficial to the viral survival and reproduction. However, the biological functions of some HSV-1-encoded proteins are not fully understood. Nuclear factor κB (NF-κB) activation is the major antiviral innate response, which can be triggered by various signals induced by cellular receptors from different pathways. Here, we demonstrated that HSV-1 UL2 protein could antagonize the tumor necrosis factor α (TNF-α)-mediated NF-κB activation. Co-immunoprecipitation assays showed that UL2 could interact with the NF-κB subunits p65 and p50, which also revealed the region of amino acids 9 to 17 of UL2 could suppress the NF-κB activation and interact with p65 and p50, and UL2 bound to the immunoglobulin-like plexin transcription factor functional domain of p65. However, UL2 did not affect the formation of p65/p50 dimerization and their nuclear localizations. Yet, UL2 was demonstrated to inhibit the NF-κB activity by attenuating TNF-α-induced p65 phosphorylation at Ser536 and therefore decreasing the expression of downstream inflammatory chemokine interleukin 8. Taken together, the attenuation of NF-κB activation by UL2 may contribute to the escape of host's antiviral innate immunity for HSV-1 during its infection.
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Affiliation(s)
- Mingsheng Cai
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Zongmin Liao
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China.,Department of Scientific Research and Education, Yuebei People's Hospital, Shaoguan, China
| | - Xingmei Zou
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Zuo Xu
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Yuanfang Wang
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Tong Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Yiwen Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Xiaowen Ou
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Yangxi Deng
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Yingjie Guo
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
| | - Tao Peng
- State Key Laboratory of Respiratory Diseases, Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, China.,South China Vaccine Corporation Limited, Guangzhou Science Park, Guangzhou, China
| | - Meili Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, The Second Affiliated Hospital of Guangzhou Medical University, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou, China
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14
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Savva R. The Essential Co-Option of Uracil-DNA Glycosylases by Herpesviruses Invites Novel Antiviral Design. Microorganisms 2020; 8:microorganisms8030461. [PMID: 32214054 PMCID: PMC7143999 DOI: 10.3390/microorganisms8030461] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/20/2020] [Accepted: 03/21/2020] [Indexed: 01/10/2023] Open
Abstract
Vast evolutionary distances separate the known herpesviruses, adapted to colonise specialised cells in predominantly vertebrate hosts. Nevertheless, the distinct herpesvirus families share recognisably related genomic attributes. The taxonomic Family Herpesviridae includes many important human and animal pathogens. Successful antiviral drugs targeting Herpesviridae are available, but the need for reduced toxicity and improved efficacy in critical healthcare interventions invites novel solutions: immunocompromised patients presenting particular challenges. A conserved enzyme required for viral fitness is Ung, a uracil-DNA glycosylase, which is encoded ubiquitously in Herpesviridae genomes and also host cells. Research investigating Ung in Herpesviridae dynamics has uncovered an unexpected combination of viral co-option of host Ung, along with remarkable Subfamily-specific exaptation of the virus-encoded Ung. These enzymes apparently play essential roles, both in the maintenance of viral latency and during initiation of lytic replication. The ubiquitously conserved Ung active site has previously been explored as a therapeutic target. However, exquisite selectivity and better drug-like characteristics might instead be obtained via targeting structural variations within another motif of catalytic importance in Ung. The motif structure is unique within each Subfamily and essential for viral survival. This unique signature in highly conserved Ung constitutes an attractive exploratory target for the development of novel beneficial therapeutics.
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Affiliation(s)
- Renos Savva
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
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15
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Li M, Zou X, Wang Y, Xu Z, Ou X, Li Y, Liu D, Guo Y, Deng Y, Jiang S, Li T, Shi S, Bao Y, Peng T, Cai M. The nuclear localization signal-mediated nuclear targeting of herpes simplex virus 1 early protein UL2 is important for efficient viral production. Aging (Albany NY) 2020; 12:2921-2938. [PMID: 32035424 PMCID: PMC7041738 DOI: 10.18632/aging.102786] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 01/19/2020] [Indexed: 12/18/2022]
Abstract
Herpes simplex virus 1 (HSV-1) is a representative alphaherpesvirus that can provoke a series of severe diseases to human being, but its exact pathogenesis is not perfectly understood. UL2, a uracil-DNA glycosylase involved in the process of HSV-1 DNA replication, has been shown to be predominantly targeted to the nuclei in our previous study, yet little is established regarding the subcellular localization signal or its related function of UL2 during HSV-1 propagation. Here, by creating a number of UL2 variants merged with enhanced yellow fluorescent protein, an authentic nuclear localization signal (NLS) of UL2 was, for the first time, identified and profiled to amino acids (aa) 1 to 17 (MKRACSRSPSPRRRPSS), and 12RRR14 was indispensable for its nuclear accumulation. Besides, the predicted nuclear export signal (aa 225 to 240) of UL2 was determined to be nonfunctional. Based on the HSV-1 bacterial artificial chromosome and homologous recombination technique, three recombinant viruses with mutations of the identified NLS, deletion and revertant of UL2 were constructed to assess the effect of UL2 nuclear targeting on HSV-1 replication. Compared to the wild type HSV-1, UL2 deletion remarkably restrained viral production, and mutation of NLS targeting UL2 to cytoplasm (pan-cellular distribution) in recombinant virus-infected cells showed a certain degree of deficiency in HSV-1 proliferation. Moreover, recombinant virus with UL2 deletion exhibited serious damages of viral DNA synthesis and mRNA expression, and these processes were partially disrupted in the recombinant virus with UL2 NLS mutation. Collectively, we had established a functional NLS in UL2 and showed that the NLS-mediated nuclear translocation of UL2 was important for efficient production of HSV-1. These data were of significance for further clarifying the biological function of UL2 during HSV-1 infection.
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Affiliation(s)
- Meili Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Xingmei Zou
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Yuanfang Wang
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Zuo Xu
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Xiaowen Ou
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Yiwen Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Delong Liu
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Yingjie Guo
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Yangxi Deng
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Si Jiang
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Tong Li
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Shaoxuan Shi
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Yilong Bao
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
| | - Tao Peng
- State Key Laboratory of Respiratory Diseases, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Panyu, Guangzhou 511436, Guangdong, China.,South China Vaccine Corporation Limited, Guangzhou Science Park, Guangzhou 510663, Guangdong, China
| | - Mingsheng Cai
- Guangdong Provincial Key Laboratory of Allergy and Clinical Immunology, Second Affiliated Hospital of Guangzhou Medical University, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510260, Guangdong, China
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16
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Cheng AZ, Moraes SN, Attarian C, Yockteng-Melgar J, Jarvis MC, Biolatti M, Galitska G, Dell'Oste V, Frappier L, Bierle CJ, Rice SA, Harris RS. A Conserved Mechanism of APOBEC3 Relocalization by Herpesviral Ribonucleotide Reductase Large Subunits. J Virol 2019; 93:e01539-19. [PMID: 31534038 PMCID: PMC6854502 DOI: 10.1128/jvi.01539-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 09/17/2019] [Indexed: 01/04/2023] Open
Abstract
An integral part of the antiviral innate immune response is the APOBEC3 family of single-stranded DNA cytosine deaminases, which inhibits virus replication through deamination-dependent and -independent activities. Viruses have evolved mechanisms to counteract these enzymes, such as HIV-1 Vif-mediated formation of a ubiquitin ligase to degrade virus-restrictive APOBEC3 enzymes. A new example is Epstein-Barr virus (EBV) ribonucleotide reductase (RNR)-mediated inhibition of cellular APOBEC3B (A3B). The large subunit of the viral RNR, BORF2, causes A3B relocalization from the nucleus to cytoplasmic bodies and thereby protects viral DNA during lytic replication. Here, we use coimmunoprecipitation and immunofluorescence microscopy approaches to ask whether this mechanism is shared with the closely related gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) and the more distantly related alphaherpesvirus herpes simplex virus 1 (HSV-1). The large RNR subunit of KSHV, open reading frame 61 (ORF61), coprecipitated multiple APOBEC3s, including A3B and APOBEC3A (A3A). KSHV ORF61 also caused relocalization of these two enzymes to perinuclear bodies (A3B) and to oblong cytoplasmic structures (A3A). The large RNR subunit of HSV-1, ICP6, also coprecipitated A3B and A3A and was sufficient to promote the relocalization of these enzymes from nuclear to cytoplasmic compartments. HSV-1 infection caused similar relocalization phenotypes that required ICP6. However, unlike the infectivity defects previously reported for BORF2-null EBV, ICP6 mutant HSV-1 showed normal growth rates and plaque phenotypes. Combined, these results indicate that both gamma- and alphaherpesviruses use a conserved RNR-dependent mechanism to relocalize A3B and A3A and furthermore suggest that HSV-1 possesses at least one additional mechanism to neutralize these antiviral enzymes.IMPORTANCE The APOBEC3 family of DNA cytosine deaminases constitutes a vital innate immune defense against a range of different viruses. A novel counterrestriction mechanism has recently been uncovered for the gammaherpesvirus EBV, in which a subunit of the viral protein known to produce DNA building blocks (ribonucleotide reductase) causes A3B to relocalize from the nucleus to the cytosol. Here, we extend these observations with A3B to include a closely related gammaherpesvirus, KSHV, and a more distantly related alphaherpesvirus, HSV-1. These different viral ribonucleotide reductases also caused relocalization of A3A, which is 92% identical to A3B. These studies are important because they suggest a conserved mechanism of APOBEC3 evasion by large double-stranded DNA herpesviruses. Strategies to block this host-pathogen interaction may be effective for treating infections caused by these herpesviruses.
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Affiliation(s)
- Adam Z Cheng
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA
| | - Sofia N Moraes
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA
| | - Claire Attarian
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA
| | - Jaime Yockteng-Melgar
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Facultad de Ciencias de la Vida, Escuela Superior Politécnica del Litoral, Guayaquil, Ecuador
| | - Matthew C Jarvis
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA
| | - Matteo Biolatti
- Laboratory of Pathogenesis of Viral Infections, Department of Public Health and Pediatric Sciences, University of Turin, Turin, Italy
| | - Ganna Galitska
- Laboratory of Pathogenesis of Viral Infections, Department of Public Health and Pediatric Sciences, University of Turin, Turin, Italy
| | - Valentina Dell'Oste
- Laboratory of Pathogenesis of Viral Infections, Department of Public Health and Pediatric Sciences, University of Turin, Turin, Italy
| | - Lori Frappier
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Craig J Bierle
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Stephen A Rice
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota, USA
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17
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Combinatorial Loss of the Enzymatic Activities of Viral Uracil-DNA Glycosylase and Viral dUTPase Impairs Murine Gammaherpesvirus Pathogenesis and Leads to Increased Recombination-Based Deletion in the Viral Genome. mBio 2018; 9:mBio.01831-18. [PMID: 30377280 PMCID: PMC6212821 DOI: 10.1128/mbio.01831-18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Unrepaired uracils in DNA can lead to mutations and compromise genomic stability. Herpesviruses have hijacked host processes of DNA repair and nucleotide metabolism by encoding a viral UNG that excises uracils and a viral dUTPase that initiates conversion of dUTP to dTTP. To better understand the impact of these processes on gammaherpesvirus pathogenesis, we examined the separate and collaborative roles of vUNG and vDUT upon MHV68 infection of mice. Simultaneous disruption of the enzymatic activities of both vUNG and vDUT led to a severe defect in acute replication and establishment of latency, while also revealing a novel, combinatorial function in promoting viral genomic stability. We propose that herpesviruses require these enzymatic processes to protect the viral genome from damage, possibly triggered by misincorporated uracil. This reveals a novel point of therapeutic intervention to potentially block viral replication and reduce the fitness of multiple herpesviruses. Misincorporation of uracil or spontaneous cytidine deamination is a common mutagenic insult to DNA. Herpesviruses encode a viral uracil-DNA glycosylase (vUNG) and a viral dUTPase (vDUT), each with enzymatic and nonenzymatic functions. However, the coordinated roles of these enzymatic activities in gammaherpesvirus pathogenesis and viral genomic stability have not been defined. In addition, potential compensation by the host UNG has not been examined in vivo. The genetic tractability of the murine gammaherpesvirus 68 (MHV68) system enabled us to delineate the contribution of host and viral factors that prevent uracilated DNA. Recombinant MHV68 lacking vUNG (ORF46.stop) was not further impaired for acute replication in the lungs of UNG−/− mice compared to wild-type (WT) mice, indicating host UNG does not compensate for the absence of vUNG. Next, we investigated the separate and combinatorial consequences of mutating the catalytic residues of the vUNG (ORF46.CM) and vDUT (ORF54.CM). ORF46.CM was not impaired for replication, while ORF54.CM had a slight transient defect in replication in the lungs. However, disabling both vUNG and vDUT led to a significant defect in acute expansion in the lungs, followed by impaired establishment of latency in the splenic reservoir. Upon serial passage of the ORF46.CM/ORF54.CM mutant in either fibroblasts or the lungs of mice, we noted rapid loss of the nonessential yellow fluorescent protein (YFP) reporter gene from the viral genome, due to recombination at repetitive elements. Taken together, our data indicate that the vUNG and vDUT coordinate to promote viral genomic stability and enable viral expansion prior to colonization of latent reservoirs.
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Cai M, Huang Z, Liao Z, Chen T, Wang P, Jiang S, Chen D, Peng T, Bian Y, Hong G, Yang H, Zeng Z, Li X, Li M. Characterization of the subcellular localization and nuclear import molecular mechanisms of herpes simplex virus 1 UL2. Biol Chem 2017; 398:509-517. [PMID: 27865090 DOI: 10.1515/hsz-2016-0268] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Accepted: 11/16/2016] [Indexed: 11/15/2022]
Abstract
As a crucial protein, the herpes simplex virus 1 (HSV-1) UL2 protein has been shown to take part in various stages of viral infection, nonetheless, its exact subcellular localization and transport molecular determinants are not well known thus far. In the present study, by using live cells fluorescent microscopy assay, UL2 tagged with enhanced yellow fluorescent protein was transiently expressed in live cells and showed a completely nuclear accumulation without the presence of other HSV-1 proteins. Moreover, the nuclear transport of UL2 was characterized to be assisted by multiple transport pathways through Ran-, importin α1-, α5-, α7-, β1- and transportin-1 cellular transport receptors. Consequently, these results will improve understanding of UL2-mediated biological functions in HSV-1 infection cycles.
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Irwin CR, Hitt MM, Evans DH. Targeting Nucleotide Biosynthesis: A Strategy for Improving the Oncolytic Potential of DNA Viruses. Front Oncol 2017; 7:229. [PMID: 29018771 PMCID: PMC5622948 DOI: 10.3389/fonc.2017.00229] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/07/2017] [Indexed: 12/14/2022] Open
Abstract
The rapid growth of tumors depends upon elevated levels of dNTPs, and while dNTP concentrations are tightly regulated in normal cells, this control is often lost in transformed cells. This feature of cancer cells has been used to advantage to develop oncolytic DNA viruses. DNA viruses employ many different mechanisms to increase dNTP levels in infected cells, because the low concentration of dNTPs found in non-cycling cells can inhibit virus replication. By disrupting the virus-encoded gene(s) that normally promote dNTP biosynthesis, one can assemble oncolytic versions of these agents that replicate selectively in cancer cells. This review covers the pathways involved in dNTP production, how they are dysregulated in cancer cells, and the various approaches that have been used to exploit this biology to improve the tumor specificity of oncolytic viruses. In particular, we compare and contrast the ways that the different types of oncolytic virus candidates can directly modulate these processes. We limit our review to the large DNA viruses that naturally encode homologs of the cellular enzymes that catalyze dNTP biogenesis. Lastly, we consider how this knowledge might guide future development of oncolytic viruses.
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Affiliation(s)
- Chad R Irwin
- Faculty of Medicine and Dentistry, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,Faculty of Medicine and Dentistry, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB, Canada
| | - Mary M Hitt
- Faculty of Medicine and Dentistry, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB, Canada.,Faculty of Medicine and Dentistry, Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - David H Evans
- Faculty of Medicine and Dentistry, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,Faculty of Medicine and Dentistry, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB, Canada
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20
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Topalis D, Gillemot S, Snoeck R, Andrei G. Distribution and effects of amino acid changes in drug-resistant α and β herpesviruses DNA polymerase. Nucleic Acids Res 2016; 44:9530-9554. [PMID: 27694307 PMCID: PMC5175367 DOI: 10.1093/nar/gkw875] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 09/13/2016] [Accepted: 09/21/2016] [Indexed: 12/15/2022] Open
Abstract
Emergence of drug-resistance to all FDA-approved antiherpesvirus agents is an increasing concern in immunocompromised patients. Herpesvirus DNA polymerase (DNApol) is currently the target of nucleos(t)ide analogue-based therapy. Mutations in DNApol that confer resistance arose in immunocompromised patients infected with herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV), and to lesser extent in herpes simplex virus 2 (HSV-2), varicella zoster virus (VZV) and human herpesvirus 6 (HHV-6). In this review, we present distinct drug-resistant mutational profiles of herpesvirus DNApol. The impact of specific DNApol amino acid changes on drug-resistance is discussed. The pattern of genetic variability related to drug-resistance differs among the herpesviruses. Two mutational profiles appeared: one favoring amino acid changes in the Palm and Finger domains of DNApol (in α-herpesviruses HSV-1, HSV-2 and VZV), and another with mutations preferentially in the 3′-5′ exonuclease domain (in β-herpesvirus HCMV and HHV-6). The mutational profile was also related to the class of compound to which drug-resistance emerged.
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Affiliation(s)
- D Topalis
- Rega Institute for Medical Research, Department Microbiology and Immunology, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - S Gillemot
- Rega Institute for Medical Research, Department Microbiology and Immunology, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - R Snoeck
- Rega Institute for Medical Research, Department Microbiology and Immunology, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - G Andrei
- Rega Institute for Medical Research, Department Microbiology and Immunology, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
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21
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Wang HC, Ho CH, Chou CC, Ko TP, Huang MF, Hsu KC, Wang AHJ. Using structural-based protein engineering to modulate the differential inhibition effects of SAUGI on human and HSV uracil DNA glycosylase. Nucleic Acids Res 2016; 44:4440-9. [PMID: 26980279 PMCID: PMC4872100 DOI: 10.1093/nar/gkw185] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 03/09/2016] [Indexed: 02/06/2023] Open
Abstract
Uracil-DNA glycosylases (UDGs) are highly conserved proteins that can be found in a wide range of organisms, and are involved in the DNA repair and host defense systems. UDG activity is controlled by various cellular factors, including the uracil-DNA glycosylase inhibitors, which are DNA mimic proteins that prevent the DNA binding sites of UDGs from interacting with their DNA substrate. To date, only three uracil-DNA glycosylase inhibitors, phage UGI, p56, and Staphylococcus aureus SAUGI, have been determined. We show here that SAUGI has differential inhibitory effects on UDGs from human, bacteria, Herpes simplex virus (HSV; human herpesvirus 1) and Epstein-Barr virus (EBV; human herpesvirus 4). Newly determined crystal structures of SAUGI/human UDG and a SAUGI/HSVUDG complex were used to explain the differential binding activities of SAUGI on these two UDGs. Structural-based protein engineering was further used to modulate the inhibitory ability of SAUGI on human UDG and HSVUDG. The results of this work extend our understanding of DNA mimics as well as potentially opening the way for novel therapeutic applications for this kind of protein.
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Affiliation(s)
- Hao-Ching Wang
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan
| | - Chun-Han Ho
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan
| | - Chia-Cheng Chou
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Tzu-Ping Ko
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Ming-Fen Huang
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan
| | - Kai-Cheng Hsu
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan
| | - Andrew H-J Wang
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan Core Facilities for Protein Structural Analysis, Academia Sinica, Taipei 115, Taiwan
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22
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Willems L, Gillet NA. APOBEC3 Interference during Replication of Viral Genomes. Viruses 2015; 7:2999-3018. [PMID: 26110583 PMCID: PMC4488724 DOI: 10.3390/v7062757] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 05/26/2015] [Accepted: 06/04/2015] [Indexed: 01/05/2023] Open
Abstract
Co-evolution of viruses and their hosts has reached a fragile and dynamic equilibrium that allows viral persistence, replication and transmission. In response, infected hosts have developed strategies of defense that counteract the deleterious effects of viral infections. In particular, single-strand DNA editing by Apolipoprotein B Editing Catalytic subunits proteins 3 (APOBEC3s) is a well-conserved mechanism of mammalian innate immunity that mutates and inactivates viral genomes. In this review, we describe the mechanisms of APOBEC3 editing during viral replication, the viral strategies that prevent APOBEC3 activity and the consequences of APOBEC3 modulation on viral fitness and host genome integrity. Understanding the mechanisms involved reveals new prospects for therapeutic intervention.
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Affiliation(s)
- Luc Willems
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) of University of Liège (ULg), B34, 1 avenue de L'Hôpital, Sart-Tilman Liège 4000, Belgium.
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 13 avenue Maréchal Juin, Gembloux 5030, Belgium.
| | - Nicolas Albert Gillet
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) of University of Liège (ULg), B34, 1 avenue de L'Hôpital, Sart-Tilman Liège 4000, Belgium.
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 13 avenue Maréchal Juin, Gembloux 5030, Belgium.
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23
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Absence of the uracil DNA glycosylase of murine gammaherpesvirus 68 impairs replication and delays the establishment of latency in vivo. J Virol 2015; 89:3366-79. [PMID: 25589640 DOI: 10.1128/jvi.03111-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
UNLABELLED Uracil DNA glycosylases (UNG) are highly conserved proteins that preserve DNA fidelity by catalyzing the removal of mutagenic uracils. All herpesviruses encode a viral UNG (vUNG), and yet the role of the vUNG in a pathogenic course of gammaherpesvirus infection is not known. First, we demonstrated that the vUNG of murine gammaherpesvirus 68 (MHV68) retains the enzymatic function of host UNG in an in vitro class switch recombination assay. Next, we generated a recombinant MHV68 with a stop codon in ORF46/UNG (ΔUNG) that led to loss of UNG activity in infected cells and a replication defect in primary fibroblasts. Acute replication of MHV68ΔUNG in the lungs of infected mice was reduced 100-fold and was accompanied by a substantial delay in the establishment of splenic latency. Latency was largely, yet not fully, restored by an increase in virus inoculum or by altering the route of infection. MHV68 reactivation from latent splenocytes was not altered in the absence of the vUNG. A survey of host UNG activity in cells and tissues targeted by MHV68 indicated that the lung tissue has a lower level of enzymatic UNG activity than the spleen. Taken together, these results indicate that the vUNG plays a critical role in the replication of MHV68 in tissues with limited host UNG activity and this vUNG-dependent expansion, in turn, influences the kinetics of latency establishment in distal reservoirs. IMPORTANCE Herpesviruses establish chronic lifelong infections using a strategy of replicative expansion, dissemination to latent reservoirs, and subsequent reactivation for transmission and spread. We examined the role of the viral uracil DNA glycosylase, a protein conserved among all herpesviruses, in replication and latency of murine gammaherpesvirus 68. We report that the viral UNG of this murine pathogen retains catalytic activity and influences replication in culture. The viral UNG was impaired for productive replication in the lung. This defect in expansion at the initial site of acute replication was associated with a substantial delay of latency establishment in the spleen. The levels of host UNG were substantially lower in the lung compared to the spleen, suggesting that herpesviruses encode a viral UNG to compensate for reduced host enzyme levels in some cell types and tissues. These data suggest that intervention at the site of initial replicative expansion can delay the establishment of latency, a hallmark of chronic herpesvirus infection.
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24
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Kukhanova MK, Korovina AN, Kochetkov SN. Human herpes simplex virus: Life cycle and development of inhibitors. BIOCHEMISTRY (MOSCOW) 2015; 79:1635-52. [DOI: 10.1134/s0006297914130124] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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25
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James SH, Larson KB, Acosta EP, Prichard MN. Helicase-primase as a target of new therapies for herpes simplex virus infections. Clin Pharmacol Ther 2014; 97:66-78. [PMID: 25670384 DOI: 10.1002/cpt.3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 09/16/2014] [Indexed: 01/13/2023]
Abstract
The seminal discovery of acyclovir 40 years ago heralded the modern era of truly selective antiviral therapies and this drug remains the therapy of choice for herpes simplex virus infections. Yet by modern standards, its antiviral activity is modest and new drugs against novel molecular targets such as the helicase-primase have the potential to improve clinical outcome, particularly in high-risk patients. A brief synopsis of current therapies for these infections and clinical need is provided to help provide an initial perspective. The function of the helicase-primase complex is then summarized and the development of new inhibitors of the helicase-primase complex, such as pritelivir and amenamevir, is discussed. We review their mechanism of action, propensity for drug resistance, and pharmacokinetic characteristics and discuss their potential to advance current therapeutic options. Strategies that include combinations of these inhibitors with acyclovir are also considered, as they will likely maximize clinical efficacy.
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Affiliation(s)
- S H James
- Division of Infectious Diseases, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama, USA
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26
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Schormann N, Ricciardi R, Chattopadhyay D. Uracil-DNA glycosylases-structural and functional perspectives on an essential family of DNA repair enzymes. Protein Sci 2014; 23:1667-85. [PMID: 25252105 DOI: 10.1002/pro.2554] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 09/16/2014] [Indexed: 12/26/2022]
Abstract
Uracil-DNA glycosylases (UDGs) are evolutionarily conserved DNA repair enzymes that initiate the base excision repair pathway and remove uracil from DNA. The UDG superfamily is classified into six families based on their substrate specificity. This review focuses on the family I enzymes since these are the most extensively studied members of the superfamily. The structural basis for substrate specificity and base recognition as well as for DNA binding, nucleotide flipping and catalytic mechanism is discussed in detail. Other topics include the mechanism of lesion search and molecular mimicry through interaction with uracil-DNA glycosylase inhibitors. The latest studies and findings detailing structure and function in the UDG superfamily are presented.
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Affiliation(s)
- N Schormann
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, 35294
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27
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Uracil DNA glycosylase BKRF3 contributes to Epstein-Barr virus DNA replication through physical interactions with proteins in viral DNA replication complex. J Virol 2014; 88:8883-99. [PMID: 24872582 DOI: 10.1128/jvi.00950-14] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Epstein-Barr virus (EBV) BKRF3 shares sequence homology with members of the uracil-N-glycosylase (UNG) protein family and has DNA glycosylase activity. Here, we explored how BKRF3 participates in the DNA replication complex and contributes to viral DNA replication. Exogenously expressed Flag-BKRF3 was distributed mostly in the cytoplasm, whereas BKRF3 was translocated into the nucleus and colocalized with the EBV DNA polymerase BALF5 in the replication compartment during EBV lytic replication. The expression level of BKRF3 increased gradually during viral replication, coupled with a decrease of cellular UNG2, suggesting BKRF3 enzyme activity compensates for UNG2 and ensures the fidelity of viral DNA replication. In immunoprecipitation-Western blotting, BKRF3 was coimmuno-precipitated with BALF5, the polymerase processivity factor BMRF1, and the immediate-early transactivator Rta. Coexpression of BMRF1 appeared to facilitate the nuclear targeting of BKRF3 in immunofluorescence staining. Residues 164 to 255 of BKRF3 were required for interaction with Rta and BALF5, whereas residues 81 to 166 of BKRF3 were critical for BMRF1 interaction in glutathione S-transferase (GST) pulldown experiments. Viral DNA replication was defective in cells harboring BKRF3 knockout EBV bacmids. In complementation assays, the catalytic mutant BKRF3(Q90L,D91N) restored viral DNA replication, whereas the leucine loop mutant BKRF3(H213L) only partially rescued viral DNA replication, coupled with a reduced ability to interact with the viral DNA polymerase and Rta. Our data suggest that BKRF3 plays a critical role in viral DNA synthesis predominantly through its interactions with viral proteins in the DNA replication compartment, while its enzymatic activity may be supplementary for uracil DNA glycosylase (UDG) function during virus replication. IMPORTANCE Catalytic activities of both cellular UDG UNG2 and viral UDGs contribute to herpesviral DNA replication. To ensure that the enzyme activity executes at the right time and the right place in DNA replication forks, complex formation with other components in the DNA replication machinery provides an important regulation for UDG function. In this study, we provide the mechanism for EBV UDG BKRF3 nuclear targeting and the interacting domains of BKRF3 with viral DNA replication proteins. Through knockout and complementation approaches, we further demonstrate that in addition to UDG activity, the interaction of BKRF3 with viral proteins in the replication compartment is crucial for efficient viral DNA replication.
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28
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Argininosuccinate synthetase 1 depletion produces a metabolic state conducive to herpes simplex virus 1 infection. Proc Natl Acad Sci U S A 2013; 110:E5006-15. [PMID: 24297925 DOI: 10.1073/pnas.1321305110] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Herpes simplex virus 1 (HSV-1) infection triggers specific metabolic changes in its host cell. To explore the interactions between cellular metabolism and HSV-1 infection, we performed an siRNA screen of cellular metabolic genes, measuring their effect on viral replication. The screen identified multiple enzymes predicted to influence HSV-1 replication, including argininosuccinate synthetase 1 (AS1), which consumes aspartate as part of de novo arginine synthesis. Knockdown of AS1 robustly enhanced viral genome replication and the production of infectious virus. Using high-resolution liquid chromatography-mass spectrometry, we found that the metabolic phenotype induced by knockdown of AS1 in human fibroblasts mimicked multiple aspects of the metabolic program observed during HSV-1 infection, including an increase in multiple nucleotides and their precursors. Together with the observation that AS1 protein and mRNA levels decrease during wild-type infection, this work suggests that reduced AS1 activity is partially responsible for the metabolic program induced by infection.
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29
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30
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Abstract
Herpes simplex virus (HSV) encodes seven proteins necessary for viral DNA synthesis-UL9 (origin-binding protein), ICP8 (single-strand DNA [ssDNA]-binding protein), UL30/UL42 (polymerase), and UL5/UL8/UL52 (helicase/primase). It is our intention to provide an up-to-date analysis of our understanding of the structures of these replication proteins and how they function during HSV replication. The potential roles of host repair and recombination proteins will also be discussed.
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Affiliation(s)
- Sandra K Weller
- Department of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, Connecticut 06030-3205, USA.
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31
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Goellner EM, Svilar D, Almeida KH, Sobol RW. Targeting DNA polymerase ß for therapeutic intervention. Curr Mol Pharmacol 2012; 5:68-87. [PMID: 22122465 PMCID: PMC3894524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2010] [Revised: 01/10/2011] [Accepted: 01/15/2011] [Indexed: 05/31/2023]
Abstract
DNA damage plays a causal role in numerous disease processes. Hence, it is suggested that DNA repair proteins, which maintain the integrity of the nuclear and mitochondrial genomes, play a critical role in reducing the onset of multiple diseases, including cancer, diabetes and neurodegeneration. As the primary DNA polymerase involved in base excision repair, DNA polymerase ß (Polß) has been implicated in multiple cellular processes, including genome maintenance and telomere processing and is suggested to play a role in oncogenic transformation, cell viability following stress and the cellular response to radiation, chemotherapy and environmental genotoxicants. Therefore, Polß inhibitors may prove to be effective in cancer treatment. However, Polß has a complex and highly regulated role in DNA metabolism. This complicates the development of effective Polß-specific inhibitors useful for improving chemotherapy and radiation response without impacting normal cellular function. With multiple enzymatic activities, numerous binding partners and complex modes of regulation from post-translational modifications, there are many opportunities for Polß inhibition that have yet to be resolved. To shed light on the varying possibilities and approaches of targeting Polß for potential therapeutic intervention, we summarize the reported small molecule inhibitors of Polß and discuss the genetic, biochemical and chemical studies that implicate additional options for Polß inhibition. Further, we offer suggestions on possible inhibitor combinatorial approaches and the potential for tumor specificity for Polß-inhibitors.
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Affiliation(s)
- Eva M. Goellner
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA 15213, USA
| | - David Svilar
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA 15213, USA
| | - Karen H. Almeida
- Department of Physical Sciences, Rhode Island College, 600 Mt. Pleasant Ave, Providence, RI 02908-1991, USA
| | - Robert W. Sobol
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA 15213, USA
- Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15261, USA
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32
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Boyle KA, Stanitsa ES, Greseth MD, Lindgren JK, Traktman P. Evaluation of the role of the vaccinia virus uracil DNA glycosylase and A20 proteins as intrinsic components of the DNA polymerase holoenzyme. J Biol Chem 2011; 286:24702-13. [PMID: 21572084 PMCID: PMC3137046 DOI: 10.1074/jbc.m111.222216] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 05/09/2011] [Indexed: 01/04/2023] Open
Abstract
The vaccinia virus DNA polymerase is inherently distributive but acquires processivity by associating with a heterodimeric processivity factor comprised of the viral A20 and D4 proteins. D4 is also an enzymatically active uracil DNA glycosylase (UDG). The presence of an active repair protein as an essential component of the polymerase holoenzyme is a unique feature of the replication machinery. We have shown previously that the A20-UDG complex has a stoichiometry of ∼1:1, and our data suggest that A20 serves as a bridge between polymerase and UDG. Here we show that conserved hydrophobic residues in the N' terminus of A20 are important for its binding to UDG. Our data argue against the assembly of D4 into higher order multimers, suggesting that the processivity factor does not form a toroidal ring around the DNA. Instead, we hypothesize that the intrinsic, processive DNA scanning activity of UDG tethers the holoenzyme to the DNA template. The inclusion of UDG as an essential holoenzyme component suggests that replication and base excision repair may be coupled. Here we show that the DNA polymerase can utilize dUTP as a substrate in vitro. Moreover, uracil moieties incorporated into the nascent strand during holoenzyme-mediated DNA synthesis can be excised by the viral UDG present within this holoenzyme, leaving abasic sites. Finally, we show that the polymerase stalls upon encountering an abasic site in the template strand, indicating that, like many replicative polymerases, the poxviral holoenzyme cannot perform translesion synthesis across an abasic site.
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Affiliation(s)
- Kathleen A. Boyle
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Eleni S. Stanitsa
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Matthew D. Greseth
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Jill K. Lindgren
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Paula Traktman
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
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33
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Divergent effects of human cytomegalovirus and herpes simplex virus-1 on cellular metabolism. PLoS Pathog 2011; 7:e1002124. [PMID: 21779165 PMCID: PMC3136460 DOI: 10.1371/journal.ppat.1002124] [Citation(s) in RCA: 276] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 05/03/2011] [Indexed: 12/27/2022] Open
Abstract
Viruses rely on the metabolic network of the host cell to provide energy and macromolecular precursors to fuel viral replication. Here we used mass spectrometry to examine the impact of two related herpesviruses, human cytomegalovirus (HCMV) and herpes simplex virus type-1 (HSV-1), on the metabolism of fibroblast and epithelial host cells. Each virus triggered strong metabolic changes that were conserved across different host cell types. The metabolic effects of the two viruses were, however, largely distinct. HCMV but not HSV-1 increased glycolytic flux. HCMV profoundly increased TCA compound levels and flow of two carbon units required for TCA cycle turning and fatty acid synthesis. HSV-1 increased anapleurotic influx to the TCA cycle through pyruvate carboxylase, feeding pyrimidine biosynthesis. Thus, these two related herpesviruses drive diverse host cells to execute distinct, virus-specific metabolic programs. Current drugs target nucleotide metabolism for treatment of both viruses. Although our results confirm that this is a robust target for HSV-1, therapeutic interventions at other points in metabolism might prove more effective for treatment of HCMV. Enveloped viruses draw on cellular machinery and materials to generate copies of their genome, structural proteins, and membrane. These biosynthetic processes use the host metabolic network to provide energy and small-molecule precursors. We have investigated how two important enveloped viruses, human cytomegalovirus and herpes simplex virus-1, alter host metabolism to provide materials for viral replication. We show that rather than passively relying on basal host cell metabolic activity, both viruses actively redirect host cell metabolism, implementing divergent metabolic programs that are robust to host cell type and virus strain. Human cytomegalovirus enhances lipid biosynthesis, while herpes simplex-1 gears central carbon metabolism toward the synthesis of pyrimidine nucleotides. Consistent with these changes, human cytomegalovirus is more sensitive to inhibition of fatty acid synthesis and herpes simplex virus-1 to inhibition of central metabolic reactions leading towards pyrimidine synthesis. As these two closely related viruses have divergent metabolic strategies, and since the metabolic perturbations point to potential drug targets, an important priority is defining the metabolic programs of other viruses.
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34
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Muylaert I, Tang KW, Elias P. Replication and recombination of herpes simplex virus DNA. J Biol Chem 2011; 286:15619-24. [PMID: 21362621 DOI: 10.1074/jbc.r111.233981] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Replication of herpes simplex virus takes place in the cell nucleus and is carried out by a replisome composed of six viral proteins: the UL30-UL42 DNA polymerase, the UL5-UL8-UL52 helicase-primase, and the UL29 single-stranded DNA-binding protein ICP8. The replisome is loaded on origins of replication by the UL9 initiator origin-binding protein. Virus replication is intimately coupled to recombination and repair, often performed by cellular proteins. Here, we review new significant developments: the three-dimensional structures for the DNA polymerase, the polymerase accessory factor, and the single-stranded DNA-binding protein; the reconstitution of a functional replisome in vitro; the elucidation of the mechanism for activation of origins of DNA replication; the identification of cellular proteins actively involved in or responding to viral DNA replication; and the elucidation of requirements for formation of replication foci in the nucleus and effects on protein localization.
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Affiliation(s)
- Isabella Muylaert
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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35
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Two new subfamilies of DNA mismatch repair proteins (MutS) specifically abundant in the marine environment. ISME JOURNAL 2011; 5:1143-51. [PMID: 21248859 DOI: 10.1038/ismej.2010.210] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
MutS proteins are ubiquitous in cellular organisms and have important roles in DNA mismatch repair or recombination. In the virus world, the amoeba-infecting Mimivirus, as well as the recently sequenced Cafeteria roenbergensis virus are known to encode a MutS related to the homologs found in octocorals and ɛ-proteobacteria. To explore the presence of MutS proteins in other viral genomes, we performed a genomic survey of four giant viruses ('giruses') (Pyramimonas orientalis virus (PoV), Phaeocystis pouchetii virus (PpV), Chrysochromulina ericina virus (CeV) and Heterocapsa circularisquama DNA virus (HcDNAV)) that infect unicellular marine algae. Our analysis revealed the presence of a close homolog of Mimivirus MutS in all the analyzed giruses. These viral homologs possess a specific domain structure, including a C-terminal HNH-endonuclease domain, defining the new MutS7 subfamily. We confirmed the presence of conserved mismatch recognition residues in all members of the MutS7 subfamily, suggesting their role in DNA mismatch repair rather than DNA recombination. PoV and PpV were found to contain an additional type of MutS, which we propose to call MutS8. The MutS8 proteins in PoV and PpV were found to be closely related to homologs from 'Candidatus Amoebophilus asiaticus', an obligate intracellular amoeba-symbiont belonging to the Bacteroidetes. Furthermore, our analysis revealed that MutS7 and MutS8 are abundant in marine microbial metagenomes and that a vast majority of these environmental sequences are likely of girus origin. Giruses thus seem to represent a major source of the underexplored diversity of the MutS family in the microbial world.
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36
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Strang BL, Coen DM. Interaction of the human cytomegalovirus uracil DNA glycosylase UL114 with the viral DNA polymerase catalytic subunit UL54. J Gen Virol 2010; 91:2029-2033. [PMID: 20410316 PMCID: PMC3052538 DOI: 10.1099/vir.0.022160-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Interaction between human cytomegalovirus uracil DNA glycosylase (UL114) and the viral DNA polymerase accessory subunit (UL44) has been reported; however, no such association was found in proteomic studies of UL44-interacting proteins. Utilizing virus expressing FLAG-tagged UL114, nuclease-resistant association of UL44 and the DNA polymerase catalytic subunit UL54 with UL114 was observed by co-immunoprecipitation. Contrary to a previous report, we observed that UL114 was much less abundant than UL44. Interaction of UL114 with UL54, independent of the UL54 carboxyl terminus, but not with UL44 was detected in vitro. Our data are consistent with a direct UL114–UL54 interaction, and suggest that UL114 and UL54 act in concert during base excision repair of the viral genome.
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Affiliation(s)
- Blair L Strang
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Donald M Coen
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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