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Wakata A, Katoh H, Kato F, Takeda M. Nucleolar Protein Treacle Is Important for the Efficient Growth of Mumps Virus. J Virol 2022; 96:e0072222. [PMID: 36135364 PMCID: PMC9555161 DOI: 10.1128/jvi.00722-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The nucleolus is the largest structure in the nucleus, and it plays roles in mediating cellular stress responses and regulating cell proliferation, as well as in ribosome biosynthesis. The nucleolus is composed of a variety of nucleolar factors that interact with each other in a complex manner to enable its function. Many viral proteins interact with nucleolar factors as well, affecting cellular morphology and function. Here, to investigate the association between mumps virus (MuV) infection and the nucleolus, we evaluated the necessity of nucleolar factors for MuV proliferation by performing a knockdown of these factors with small interfering (si)RNAs. Our results reveal that suppressing the expression of Treacle, which is required for ribosome biosynthesis, reduced the proliferative potential of MuV. Additionally, the one-step growth kinetics results indicate that Treacle knockdown did not affect the viral RNA and protein synthesis of MuV, but it did impair the production of infectious virus particles. Viral matrix protein (M) was considered a candidate Treacle interaction partner because it functions in the process of particle formation in the viral life cycle and is partially localized in the nucleolus. Our data confirm that MuV M can interact with Treacle and colocalize with it in the nucleolus. Furthermore, we found that viral infection induces relocalization of Treacle in the nucleus. Together, these findings suggest that interaction with Treacle in the nucleolus is important for the M protein to exert its functions late in the MuV life cycle. IMPORTANCE The nucleolus, which is the site of ribosome biosynthesis, is a target organelle for many viruses. It is increasingly evident that viruses can favor their own replication and multiplication by interacting with various nucleolar factors. In this study, we found that the nucleolar protein Treacle, known to function in the transcription and processing of pre-rRNA, is required for the efficient propagation of mumps virus (MuV). Specifically, our data indicate that Treacle is not involved in viral RNA or protein synthesis but is important in the processes leading to viral particle production in MuV infection. Additionally, we determined that MuV matrix protein (M), which functions mainly in viral particle assembly and budding, colocalized and interacted with Treacle. Furthermore, we found that Treacle is distributed throughout the nucleus in MuV-infected cells. Our research shows that the interaction between M and Treacle supports efficient viral growth in the late stage of MuV infection.
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Affiliation(s)
- Aika Wakata
- Department of Virology III, National Institute of Infectious Diseases, Tokyo, Japan
| | - Hiroshi Katoh
- Department of Virology III, National Institute of Infectious Diseases, Tokyo, Japan
| | - Fumihiro Kato
- Department of Virology III, National Institute of Infectious Diseases, Tokyo, Japan
| | - Makoto Takeda
- Department of Virology III, National Institute of Infectious Diseases, Tokyo, Japan
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Lytic Reactivation of the Kaposi’s Sarcoma-Associated Herpesvirus (KSHV) Is Accompanied by Major Nucleolar Alterations. Viruses 2022; 14:v14081720. [PMID: 36016343 PMCID: PMC9412354 DOI: 10.3390/v14081720] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/21/2022] [Accepted: 07/28/2022] [Indexed: 02/01/2023] Open
Abstract
The nucleolus is a subnuclear compartment whose primary function is the biogenesis of ribosomal subunits. Certain viral infections affect the morphology and composition of the nucleolar compartment and influence ribosomal RNA (rRNA) transcription and maturation. However, no description of nucleolar morphology and function during infection with Kaposi’s sarcoma-associated herpesvirus (KSHV) is available to date. Using immunofluorescence microscopy, we documented extensive destruction of the nuclear and nucleolar architecture during the lytic reactivation of KSHV. This was manifested by the redistribution of key nucleolar proteins, including the rRNA transcription factor UBF. Distinct delocalization patterns were evident; certain nucleolar proteins remained together whereas others dissociated, implying that nucleolar proteins undergo nonrandom programmed dispersion. Significantly, the redistribution of UBF was dependent on viral DNA replication or late viral gene expression. No significant changes in pre-rRNA levels and no accumulation of pre-rRNA intermediates were found by RT-qPCR and Northern blot analysis. Furthermore, fluorescent in situ hybridization (FISH), combined with immunofluorescence, revealed an overlap between Fibrillarin and internal transcribed spacer 1 (ITS1), which represents the primary product of the pre-rRNA, suggesting that the processing of rRNA proceeds during lytic reactivation. Finally, small changes in the levels of pseudouridylation (Ψ) and 2′-O-methylation (Nm) were documented across the rRNA; however, none were localized to the functional domain. Taken together, our results suggest that despite dramatic changes in the nucleolar organization, rRNA transcription and processing persist during lytic reactivation of KSHV. Whether the observed nucleolar alterations favor productive infection or signify cellular anti-viral responses remains to be determined.
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Ouellet Lavallée G, Pearson A. Upstream binding factor inhibits herpes simplex virus replication. Virology 2015; 483:108-16. [PMID: 25965800 DOI: 10.1016/j.virol.2015.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 01/09/2015] [Accepted: 04/02/2015] [Indexed: 12/16/2022]
Abstract
Herpes simplex virus 1 (HSV-1) infection induces changes to the host cell nucleus including relocalization of the cellular protein Upstream Binding Factor (UBF) from the nucleolus to viral replication compartments (VRCs). Herein, we tested the hypothesis that UBF is recruited to VRCs to promote viral DNA replication. Surprisingly, infection of UBF-depleted HeLa cells with HSV-1 or HSV-2 produced higher viral titers compared to controls. Reduced expression of UBF also led to a progressive increase in the relative amount of HSV-1 DNA versus controls, and increased levels of HSV-1 ICP27 and TK mRNA and protein, regardless of whether viral DNA replication was inhibited or not. Our results suggest that UBF can inhibit gene expression from viral DNA prior to its replication. A similar but smaller effect on viral titers was observed in human foreskin fibroblasts. This is the first report of UBF having a restrictive effect on replication of a virus.
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Pentecost M, Vashisht AA, Lester T, Voros T, Beaty SM, Park A, Wang YE, Yun TE, Freiberg AN, Wohlschlegel JA, Lee B. Evidence for ubiquitin-regulated nuclear and subnuclear trafficking among Paramyxovirinae matrix proteins. PLoS Pathog 2015; 11:e1004739. [PMID: 25782006 PMCID: PMC4363627 DOI: 10.1371/journal.ppat.1004739] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 02/10/2015] [Indexed: 11/24/2022] Open
Abstract
The paramyxovirus matrix (M) protein is a molecular scaffold required for viral morphogenesis and budding at the plasma membrane. Transient nuclear residence of some M proteins hints at non-structural roles. However, little is known regarding the mechanisms that regulate the nuclear sojourn. Previously, we found that the nuclear-cytoplasmic trafficking of Nipah virus M (NiV-M) is a prerequisite for budding, and is regulated by a bipartite nuclear localization signal (NLSbp), a leucine-rich nuclear export signal (NES), and monoubiquitination of the K258 residue within the NLSbp itself (NLSbp-lysine). To define whether the sequence determinants of nuclear trafficking identified in NiV-M are common among other Paramyxovirinae M proteins, we generated the homologous NES and NLSbp-lysine mutations in M proteins from the five major Paramyxovirinae genera. Using quantitative 3D confocal microscopy, we determined that the NES and NLSbp-lysine are required for the efficient nuclear export of the M proteins of Nipah virus, Hendra virus, Sendai virus, and Mumps virus. Pharmacological depletion of free ubiquitin or mutation of the conserved NLSbp-lysine to an arginine, which inhibits M ubiquitination, also results in nuclear and nucleolar retention of these M proteins. Recombinant Sendai virus (rSeV-eGFP) bearing the NES or NLSbp-lysine M mutants rescued at similar efficiencies to wild type. However, foci of cells expressing the M mutants displayed marked fusogenicity in contrast to wild type, and infection did not spread. Recombinant Mumps virus (rMuV-eGFP) bearing the homologous mutations showed similar defects in viral morphogenesis. Finally, shotgun proteomics experiments indicated that the interactomes of Paramyxovirinae M proteins are significantly enriched for components of the nuclear pore complex, nuclear transport receptors, and nucleolar proteins. We then synthesize our functional and proteomics data to propose a working model for the ubiquitin-regulated nuclear-cytoplasmic trafficking of cognate paramyxovirus M proteins that show a consistent nuclear trafficking phenotype. Elucidating virus-cell interactions is fundamental to understanding viral replication and identifying targets for therapeutic control of viral infection. Paramyxoviruses include human and animal pathogens of medical and agricultural significance. Their matrix (M) structural protein organizes virion assembly at the plasma membrane and mediates viral budding. While nuclear localization of M proteins has been described for some paramyxoviruses, the underlying mechanisms of nuclear trafficking and the biological relevance of this observation have remained largely unexamined. Through comparative analyses of M proteins across five Paramyxovirinae genera, we identify M proteins from at least three genera that exhibit similar nuclear trafficking phenotypes regulated by an NLSbp as well as an NES sequence within M that may mediate the interaction of M with host nuclear transport receptors. Additionally, a conserved lysine within the NLSbp of some M proteins is required for nuclear export by regulating M ubiquitination. Sendai virus engineered to express a ubiquitination-defective M does not produce infectious virus but instead displays extensive cell-cell fusion while M is retained in the nucleolus. Thus, some Paramyxovirinae M proteins undergo regulated and active nuclear and subnuclear transport, a prerequisite for viral morphogenesis, which also suggests yet to be discovered roles for M in the nucleus.
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Affiliation(s)
- Mickey Pentecost
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Ajay A. Vashisht
- Department of Biological Chemistry, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Talia Lester
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Tim Voros
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Shannon M. Beaty
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Arnold Park
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Yao E. Wang
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Tatyana E Yun
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Alexander N. Freiberg
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - James A. Wohlschlegel
- Department of Biological Chemistry, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Benhur Lee
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- * E-mail:
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Kleinman CL, Doria M, Orecchini E, Giuliani E, Galardi S, De Jay N, Michienzi A. HIV-1 infection causes a down-regulation of genes involved in ribosome biogenesis. PLoS One 2014; 9:e113908. [PMID: 25462981 PMCID: PMC4252078 DOI: 10.1371/journal.pone.0113908] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/28/2014] [Indexed: 01/04/2023] Open
Abstract
HIV-1 preferentially infects CD4+ T cells, causing fundamental changes that eventually lead to the release of new viral particles and cell death. To investigate in detail alterations in the transcriptome of the CD4+ T cells upon viral infection, we sequenced polyadenylated RNA isolated from Jurkat cells infected or not with HIV-1. We found a marked global alteration of gene expression following infection, with an overall trend toward induction of genes, indicating widespread modification of the host biology. Annotation and pathway analysis of the most deregulated genes showed that viral infection produces a down-regulation of genes associated with the nucleolus, in particular those implicated in regulating the different steps of ribosome biogenesis, such as ribosomal RNA (rRNA) transcription, pre-rRNA processing, and ribosome maturation. The impact of HIV-1 infection on genes involved in ribosome biogenesis was further validated in primary CD4+ T cells. Moreover, we provided evidence by Northern Blot experiments, that host pre-rRNA processing in Jurkat cells might be perturbed during HIV-1 infection, thus strengthening the hypothesis of a crosstalk between nucleolar functions and viral pathogenesis.
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Affiliation(s)
- Claudia L. Kleinman
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital and Department of Human Genetics, McGill University, 3755 Côte Ste-Catherine Road, Montréal, Quebec, H3T 1E2, Canada
| | - Margherita Doria
- Laboratory of Immunoinfectivology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Elisa Orecchini
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Erica Giuliani
- Laboratory of Immunoinfectivology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Silvia Galardi
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Nicolas De Jay
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital and Department of Human Genetics, McGill University, 3755 Côte Ste-Catherine Road, Montréal, Quebec, H3T 1E2, Canada
| | - Alessandro Michienzi
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
- * E-mail:
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Salvetti A, Greco A. Viruses and the nucleolus: the fatal attraction. Biochim Biophys Acta Mol Basis Dis 2013; 1842:840-7. [PMID: 24378568 PMCID: PMC7135015 DOI: 10.1016/j.bbadis.2013.12.010] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/05/2013] [Accepted: 12/09/2013] [Indexed: 12/13/2022]
Abstract
Viruses are small obligatory parasites and as a consequence, they have developed sophisticated strategies to exploit the host cell's functions to create an environment that favors their own replication. A common feature of most – if not all – families of human and non-human viruses concerns their interaction with the nucleolus. The nucleolus is a multifunctional nuclear domain, which, in addition to its well-known role in ribosome biogenesis, plays several crucial other functions. Viral infection induces important nucleolar alterations. Indeed, during viral infection numerous viral components localize in nucleoli, while various host nucleolar proteins are redistributed in other cell compartments or are modified, and non-nucleolar cellular proteins reach the nucleolus. This review highlights the interactions reported between the nucleolus and some human or animal viral families able to establish a latent or productive infection, selected on the basis of their known interactions with the nucleolus and the nucleolar activities, and their links with virus replication and/or pathogenesis. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease. Most viruses interact with the nucleolus that plays a major role in virus life cycle. Virus/nucleolus interaction is crucial for virus replication and pathogenesis. Role of nucleoli in the infection with selected RNA viruses and herpes viruses
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Affiliation(s)
- Anna Salvetti
- Centre International de Recherche en Infectiologie (CIRI, International Center for Infectiology Research), Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 Allée d'Italie, 69365 Lyon CEDEX, France; LabEx Ecofect, Université de Lyon, 69007 Lyon, France.
| | - Anna Greco
- Centre International de Recherche en Infectiologie (CIRI, International Center for Infectiology Research), Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 Allée d'Italie, 69365 Lyon CEDEX, France; LabEx Ecofect, Université de Lyon, 69007 Lyon, France.
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Affiliation(s)
- Mark O. J. Olson
- Dept. Biochemistry, University of Mississippi Medical Center, North State St. 2500, Jackson, 39216 Mississippi USA
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Enhanced sensitivity of nucleoli in human proliferating cells to inhibition of protein synthesis with anisomycin. Bull Exp Biol Med 2011; 150:258-62. [PMID: 21240386 DOI: 10.1007/s10517-010-1118-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We describe the reaction of nuclei in cultured human cells from different tissues to inhibition of total protein synthesis with anisomycin - ribotoxin, which is now considered as a potential antitumor drug. It was shown that nucleoli in sensitive cells demonstrate typical reaction: under the action of the inhibitor, labile nucleolar protein, a component of RNA polymerase I transcription complex (previously called A3 antigen), rapidly migrates from the nucleolus to numerous discrete foci in the nucleoplasm. These changes are specific for translation suppression and are not induced by other influences on the cells. Migration of A3 antigen into the nucleoplasm manifests primarily in cells at the stage of DNA replication and is absent in resting cells. These results suggest that localization of A3 antigen can be a marker of artificial suppression of translation in proliferating human cells in vitro.
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Abstract
Recent advances in proteomics have been combined with traditional methods for isolation of nucleoli from mammalian and plant cells. This approach has confirmed the growing body of data showing a wide role for the nucleolus in eukaryotic cell biology beyond ribosome generation into many areas of cell function from regulation of the cell cycle, modulation of the cell stress response to innate immune responses. This has been reflected in the growing body of evidence that viruses specifically target the nucleolus by sequestering cellular nucleolar proteins or by targeting viral proteins to the nucleolus in order to maximise viral replication. This review covers those key areas and looks at the latest approaches using high‐throughput quantitative proteomics of the nucleolus in virus infected cells to gain an insight into the role of this fascinating compartment in viral infection.
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Affiliation(s)
- Julian A Hiscox
- Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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Lymberopoulos MH, Bourget A, Ben Abdeljelil N, Pearson A. Involvement of the UL24 protein in herpes simplex virus 1-induced dispersal of B23 and in nuclear egress. Virology 2011; 412:341-8. [PMID: 21316727 DOI: 10.1016/j.virol.2011.01.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 11/10/2010] [Accepted: 01/17/2011] [Indexed: 10/18/2022]
Abstract
UL24 of herpes simplex virus 1 (HSV-1) is widely conserved within the Herpesviridae family. Herein, we tested the hypothesis that UL24, which we have previously shown to induce the redistribution of nucleolin, also affects the localization of the nucleolar protein B23. We found that HSV-1-induced dispersal of B23 was dependent on UL24. The conserved N-terminal portion of UL24 was sufficient to induce the redistribution of B23 in transient transfection assays. Mutational analysis revealed that the endonuclease motif of UL24 was important for B23 dispersal in both transfected and infected cells. Nucleolar protein relocalization during HSV-1 infection was also observed in non-immortalized cells. Analysis of infected cells by electron microscopy revealed a decrease in the ratio of cytoplasmic versus nuclear viral particles in cells infected with a UL24-deficient strain compared to KOS-infected cells. Our results suggest that UL24 promotes nuclear egress of nucleocapsids during HSV-1 infection, possibly though effects on nucleoli.
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Affiliation(s)
- Maria H Lymberopoulos
- INRS-Institut Armand-Frappier, Université du Québec, 531 boul. des Prairies, Laval, Québec H7V 1B7, Canada
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Relocalization of upstream binding factor to viral replication compartments is UL24 independent and follows the onset of herpes simplex virus 1 DNA synthesis. J Virol 2010; 84:4810-5. [PMID: 20147409 DOI: 10.1128/jvi.02437-09] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Herpes simplex virus 1 (HSV-1) induces relocalization of several nucleolar proteins. We have found that, as for fibrillarin, the HSV-1-induced redistribution of two RNA polymerase I components, upstream binding factor (UBF) and RPA194, was independent of the viral protein UL24, which affects nucleolin localization. Nevertheless, the kinetics and sites of redistribution for fibrillarin and UBF differed. Interestingly, UBF remained associated with RPA194 during infection. Although UBF is redistributed to viral replication compartments during infection, we did not detect foci of UBF at early sites of viral DNA synthesis, suggesting that it may not be directly involved in this process at early times.
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Strang BL, Boulant S, Coen DM. Nucleolin associates with the human cytomegalovirus DNA polymerase accessory subunit UL44 and is necessary for efficient viral replication. J Virol 2010; 84:1771-84. [PMID: 20007282 PMCID: PMC2812382 DOI: 10.1128/jvi.01510-09] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Accepted: 11/23/2009] [Indexed: 01/04/2023] Open
Abstract
In the eukaryotic cell, DNA replication entails the interaction of multiple proteins with the DNA polymerase processivity factor PCNA. As the structure of the presumptive human cytomegalovirus (HCMV) DNA polymerase processivity factor UL44 is highly homologous to that of PCNA, we hypothesized that UL44 also interacts with numerous proteins. To investigate this possibility, recombinant HCMV expressing FLAG-tagged UL44 was generated and used to immunoprecipitate UL44 and associated proteins from infected cell lysates. Unexpectedly, nucleolin, a major protein component of the nucleolus, was identified among these proteins by mass spectrometry and Western blotting. The association of nucleolin and UL44 in infected cell lysate was confirmed by reciprocal coimmunoprecipitation in the presence and absence of nuclease. Western blotting and immunofluorescence assays demonstrated that the level of nucleolin increases during infection and that nucleolin becomes distributed throughout the nucleus. Furthermore, the colocalization of nucleolin and UL44 in infected cell nuclei was observed by immunofluorescence assays. Assays of HCMV-infected cells treated with small interfering RNA (siRNA) targeting nucleolin mRNA indicated that nucleolin was required for efficient virus production, viral DNA synthesis, and the expression of a late viral protein, with a correlation between the efficacy of knockdown and the effect on virus replication. In contrast, the level of neither global protein synthesis nor the replication of an unrelated virus (reovirus) was reduced in siRNA-treated cells. Taken together, our results indicate an association of nucleolin and UL44 in HCMV-infected cells and a role for nucleolin in viral DNA synthesis.
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Affiliation(s)
- Blair L. Strang
- Department of Biological Chemistry and Molecular Pharmacology, Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115
| | - Steeve Boulant
- Department of Biological Chemistry and Molecular Pharmacology, Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115
| | - Donald M. Coen
- Department of Biological Chemistry and Molecular Pharmacology, Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115
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Lam YW, Evans VC, Heesom KJ, Lamond AI, Matthews DA. Proteomics analysis of the nucleolus in adenovirus-infected cells. Mol Cell Proteomics 2009; 9:117-30. [PMID: 19812395 PMCID: PMC2808258 DOI: 10.1074/mcp.m900338-mcp200] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Adenoviruses replicate primarily in the host cell nucleus, and it is well
established that adenovirus infection affects the structure and function of host
cell nucleoli in addition to coding for a number of nucleolar targeted viral
proteins. Here we used unbiased proteomics methods, including high throughput
mass spectrometry coupled with stable isotope labeling by amino acids in cell
culture (SILAC) and traditional two-dimensional gel electrophoresis, to identify
quantitative changes in the protein composition of the nucleolus during
adenovirus infection. Two-dimensional gel analysis revealed changes in six
proteins. By contrast, SILAC-based approaches identified 351 proteins with 24
proteins showing at least a 2-fold change after infection. Of those, four were
previously reported to have aberrant localization and/or functional relevance
during adenovirus infection. In total, 15 proteins identified as changing in
amount by proteomics methods were examined in infected cells using confocal
microscopy. Eleven of these proteins showed altered patterns of localization in
adenovirus-infected cells. Comparing our data with the effects of actinomycin D
on the nucleolar proteome revealed that adenovirus infection apparently
specifically targets a relatively small subset of nucleolar antigens at the time
point examined.
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Affiliation(s)
- Yun W Lam
- Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong, China
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Abstract
Viruses are intracellular pathogens that have to usurp some of the cellular machineries to provide an optimal environment for their own replication. An increasing number of reports reveal that many viruses induce modifications of nuclear substructures including nucleoli, whether they replicate or not in the nucleus of infected cells. Indeed, during infection of cells with various types of human viruses, nucleoli undergo important morphological modifications. A large number of viral components traffic to and from the nucleolus where they interact with different cellular and/or viral factors, numerous host nucleolar proteins are redistributed in other cell compartments or are modified and some cellular proteins are delocalised in the nucleolus of infected cells. Well‐documented studies have established that several of these nucleolar modifications play a role in some steps of the viral cycle, and also in fundamental cellular pathways. The nucleolus itself is the place where several essential steps of the viral cycle take place. In other cases, viruses divert host nucleolar proteins from their known functions in order to exert new unexpected role(s). Copyright © 2009 John Wiley & Sons, Ltd.
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Affiliation(s)
- Anna Greco
- Université de Lyon, Lyon F-69003, France.
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