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Murray-Nerger LA, Lozano C, Burton EM, Liao Y, Ungerleider NA, Guo R, Gewurz BE. The nucleic acid binding protein SFPQ represses EBV lytic reactivation by promoting histone H1 expression. Nat Commun 2024; 15:4156. [PMID: 38755141 PMCID: PMC11099029 DOI: 10.1038/s41467-024-48333-x] [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: 10/24/2023] [Accepted: 04/29/2024] [Indexed: 05/18/2024] Open
Abstract
Epstein-Barr virus (EBV) uses a biphasic lifecycle of latency and lytic reactivation to infect >95% of adults worldwide. Despite its central role in EBV persistence and oncogenesis, much remains unknown about how EBV latency is maintained. We used a human genome-wide CRISPR/Cas9 screen to identify that the nuclear protein SFPQ was critical for latency. SFPQ supported expression of linker histone H1, which stabilizes nucleosomes and regulates nuclear architecture, but has not been previously implicated in EBV gene regulation. H1 occupied latent EBV genomes, including the immediate early gene BZLF1 promoter. Upon reactivation, SFPQ was sequestered into sub-nuclear puncta, and EBV genomic H1 occupancy diminished. Enforced H1 expression blocked EBV reactivation upon SFPQ knockout, confirming it as necessary downstream of SFPQ. SFPQ knockout triggered reactivation of EBV in B and epithelial cells, as well as of Kaposi's sarcoma-associated herpesvirus in B cells, suggesting a conserved gamma-herpesvirus role. These findings highlight SFPQ as a major regulator of H1 expression and EBV latency.
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Affiliation(s)
- Laura A Murray-Nerger
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA, 02115, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Program in Virology, Boston, MA, 02115, USA
- Center for Integrated Solutions to Infectious Diseases, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
| | - Clarisel Lozano
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA, 02115, USA
| | - Eric M Burton
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA, 02115, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Program in Virology, Boston, MA, 02115, USA
- Center for Integrated Solutions to Infectious Diseases, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
| | - Yifei Liao
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA, 02115, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Program in Virology, Boston, MA, 02115, USA
- Center for Integrated Solutions to Infectious Diseases, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA
| | | | - Rui Guo
- Department of Molecular Biology and Microbiology, Tufts University, Medford, MA, 02155, USA
| | - Benjamin E Gewurz
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA, 02115, USA.
- Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA.
- Harvard Program in Virology, Boston, MA, 02115, USA.
- Center for Integrated Solutions to Infectious Diseases, Broad Institute of Harvard and MIT, Cambridge, MA, 02142, USA.
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2
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Torne AS, Robertson ES. Epigenetic Mechanisms in Latent Epstein-Barr Virus Infection and Associated Cancers. Cancers (Basel) 2024; 16:991. [PMID: 38473352 PMCID: PMC10931536 DOI: 10.3390/cancers16050991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 02/25/2024] [Accepted: 02/25/2024] [Indexed: 03/14/2024] Open
Abstract
The Epstein-Barr Virus (EBV) is a double-stranded DNA-based human tumor virus that was first isolated in 1964 from lymphoma biopsies. Since its initial discovery, EBV has been identified as a major contributor to numerous cancers and chronic autoimmune disorders. The virus is particularly efficient at infecting B-cells but can also infect epithelial cells, utilizing an array of epigenetic strategies to establish long-term latent infection. The association with histone modifications, alteration of DNA methylation patterns in host and viral genomes, and microRNA targeting of host cell factors are core epigenetic strategies that drive interactions between host and virus, which are necessary for viral persistence and progression of EBV-associated diseases. Therefore, understanding epigenetic regulation and its role in post-entry viral dynamics is an elusive area of EBV research. Here, we present current outlooks of EBV epigenetic regulation as it pertains to viral interactions with its host during latent infection and its propensity to induce tumorigenesis. We review the important epigenetic regulators of EBV latency and explore how the strategies involved during latent infection drive differential epigenetic profiles and host-virus interactions in EBV-associated cancers.
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Affiliation(s)
| | - Erle S. Robertson
- Tumor Virology Program, Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA;
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Kong IY, Giulino-Roth L. Targeting latent viral infection in EBV-associated lymphomas. Front Immunol 2024; 15:1342455. [PMID: 38464537 PMCID: PMC10920267 DOI: 10.3389/fimmu.2024.1342455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 02/05/2024] [Indexed: 03/12/2024] Open
Abstract
Epstein-Barr virus (EBV) contributes to the development of a significant subset of human lymphomas. As a herpes virus, EBV can transition between a lytic state which is required to establish infection and a latent state where a limited number of viral antigens are expressed which allows infected cells to escape immune surveillance. Three broad latency programs have been described which are defined by the expression of viral proteins RNA, with latency I being the most restrictive expressing only EBV nuclear antigen 1 (EBNA1) and EBV-encoded small RNAs (EBERs) and latency III expressing the full panel of latent viral genes including the latent membrane proteins 1 and 2 (LMP1/2), and EBNA 2, 3, and leader protein (LP) which induce a robust T-cell response. The therapeutic use of EBV-specific T-cells has advanced the treatment of EBV-associated lymphoma, however this approach is only effective against EBV-associated lymphomas that express the latency II or III program. Latency I tumors such as Burkitt lymphoma (BL) and a subset of diffuse large B-cell lymphomas (DLBCL) evade the host immune response to EBV and are resistant to EBV-specific T-cell therapies. Thus, strategies for inducing a switch from the latency I to the latency II or III program in EBV+ tumors are being investigated as mechanisms to sensitize tumors to T-cell mediated killing. Here, we review what is known about the establishment and regulation of latency in EBV infected B-cells, the role of EBV-specific T-cells in lymphoma, and strategies to convert latency I tumors to latency II/III.
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Indari O, Ghosh S, Bal AS, James A, Garg M, Mishra A, Karmodiya K, Jha HC. Awakening the sleeping giant: Epstein-Barr virus reactivation by biological agents. Pathog Dis 2024; 82:ftae002. [PMID: 38281067 PMCID: PMC10901609 DOI: 10.1093/femspd/ftae002] [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: 03/27/2023] [Revised: 01/16/2024] [Accepted: 01/25/2024] [Indexed: 01/29/2024] Open
Abstract
Epstein-Barr virus (EBV) may cause harm in immunocompromised conditions or on stress stimuli. Various chemical agents have been utilized to induce the lytic cycle in EBV-infected cells. However, apart from chemical agents and external stress stimuli, certain infectious agents may reactivate the EBV. In addition, the acute infection of other pathogens may provide suitable conditions for EBV to thrive more and planting the roots for EBV-associated pathologies. Various bacteria such as periodontal pathogens like Aggregatibacter, Helicobacter pylori, etc. have shown to induce EBV reactivation either by triggering host cells directly or indirectly. Viruses such as Human simplex virus-1 (HSV) induce EBV reactivation by HSV US3 kinase while other viruses such as HIV, hepatitis virus, and even novel SARS-CoV-2 have also been reported to cause EBV reactivation. The eukaryotic pathogens such as Plasmodium falciparum and Aspergillus flavus can also reactivate EBV either by surface protein interaction or as an impact of aflatoxin, respectively. To highlight the underexplored niche of EBV reactivation by biological agents, we have comprehensively presented the related information in this review. This may help to shedding the light on the research gaps as well as to unveil yet unexplored mechanisms of EBV reactivation.
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Affiliation(s)
- Omkar Indari
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol Campus, Simrol, Indore 453552, India
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, United States
| | - Subhrojyoti Ghosh
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol Campus, Simrol, Indore 453552, India
| | - Adhiraj Singh Bal
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol Campus, Simrol, Indore 453552, India
| | - Ajay James
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol Campus, Simrol, Indore 453552, India
| | - Mehek Garg
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol Campus, Simrol, Indore 453552, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Krishanpal Karmodiya
- Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pune 411008, India
| | - Hem Chandra Jha
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol Campus, Simrol, Indore 453552, India
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5
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Ward BJH, Prasai K, Schaal DL, Wang J, Scott RS. A distinct isoform of lymphoid enhancer binding factor 1 (LEF1) epigenetically restricts EBV reactivation to maintain viral latency. PLoS Pathog 2023; 19:e1011873. [PMID: 38113273 PMCID: PMC10763950 DOI: 10.1371/journal.ppat.1011873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 01/03/2024] [Accepted: 11/29/2023] [Indexed: 12/21/2023] Open
Abstract
As a human tumor virus, EBV is present as a latent infection in its associated malignancies where genetic and epigenetic changes have been shown to impede cellular differentiation and viral reactivation. We reported previously that levels of the Wnt signaling effector, lymphoid enhancer binding factor 1 (LEF1) increased following EBV epithelial infection and an epigenetic reprogramming event was maintained even after loss of the viral genome. Elevated LEF1 levels are also observed in nasopharyngeal carcinoma and Burkitt lymphoma. To determine the role played by LEF1 in the EBV life cycle, we used in silico analysis of EBV type 1 and 2 genomes to identify over 20 Wnt-response elements, which suggests that LEF1 may bind directly to the EBV genome and regulate the viral life cycle. Using CUT&RUN-seq, LEF1 was shown to bind the latent EBV genome at various sites encoding viral lytic products that included the immediate early transactivator BZLF1 and viral primase BSLF1 genes. The LEF1 gene encodes various long and short protein isoforms. siRNA depletion of specific LEF1 isoforms revealed that the alternative-promoter derived isoform with an N-terminal truncation (ΔN LEF1) transcriptionally repressed lytic genes associated with LEF1 binding. In addition, forced expression of the ΔN LEF1 isoform antagonized EBV reactivation. As LEF1 repression requires histone deacetylase activity through either recruitment of or direct intrinsic histone deacetylase activity, siRNA depletion of LEF1 resulted in increased histone 3 lysine 9 and lysine 27 acetylation at LEF1 binding sites and across the EBV genome. Taken together, these results indicate a novel role for LEF1 in maintaining EBV latency and restriction viral reactivation via repressive chromatin remodeling of critical lytic cycle factors.
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Affiliation(s)
- B. J. H. Ward
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
| | - Kanchanjunga Prasai
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
| | - Danielle L. Schaal
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
| | - Jian Wang
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
| | - Rona S. Scott
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana, United States of America
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6
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Caruso LB, Maestri D, Tempera I. Three-Dimensional Chromatin Structure of the EBV Genome: A Crucial Factor in Viral Infection. Viruses 2023; 15:1088. [PMID: 37243174 PMCID: PMC10222312 DOI: 10.3390/v15051088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/19/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Epstein-Barr Virus (EBV) is a human gamma-herpesvirus that is widespread worldwide. To this day, about 200,000 cancer cases per year are attributed to EBV infection. EBV is capable of infecting both B cells and epithelial cells. Upon entry, viral DNA reaches the nucleus and undergoes a process of circularization and chromatinization and establishes a latent lifelong infection in host cells. There are different types of latency all characterized by different expressions of latent viral genes correlated with a different three-dimensional architecture of the viral genome. There are multiple factors involved in the regulation and maintenance of this three-dimensional organization, such as CTCF, PARP1, MYC and Nuclear Lamina, emphasizing its central role in latency maintenance.
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Affiliation(s)
| | - Davide Maestri
- The Wistar Institute, Philadelphia, PA 19104, USA; (L.B.C.); (D.M.)
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
| | - Italo Tempera
- The Wistar Institute, Philadelphia, PA 19104, USA; (L.B.C.); (D.M.)
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7
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Caruso LB, Guo R, Keith K, Madzo J, Maestri D, Boyle S, Wasserman J, Kossenkov A, Gewurz BE, Tempera I. The nuclear lamina binds the EBV genome during latency and regulates viral gene expression. PLoS Pathog 2022; 18:e1010400. [PMID: 35421198 PMCID: PMC9009669 DOI: 10.1371/journal.ppat.1010400] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 02/26/2022] [Indexed: 12/30/2022] Open
Abstract
The Epstein Barr virus (EBV) infects almost 95% of the population worldwide. While typically asymptomatic, EBV latent infection is associated with several malignancies of epithelial and lymphoid origin in immunocompromised individuals. In latently infected cells, the EBV genome persists as a chromatinized episome that expresses a limited set of viral genes in different patterns, referred to as latency types, which coincide with varying stages of infection and various malignancies. We have previously demonstrated that latency types correlate with differences in the composition and structure of the EBV episome. Several cellular factors, including the nuclear lamina, regulate chromatin composition and architecture. While the interaction of the viral genome with the nuclear lamina has been studied in the context of EBV lytic reactivation, the role of the nuclear lamina in controlling EBV latency has not been investigated. Here, we report that the nuclear lamina is an essential epigenetic regulator of the EBV episome. We observed that in B cells, EBV infection affects the composition of the nuclear lamina by inducing the expression of lamin A/C, but only in EBV+ cells expressing the Type III latency program. Using ChIP-Seq, we determined that lamin B1 and lamin A/C bind the EBV genome, and their binding correlates with deposition of the histone repressive mark H3K9me2. By RNA-Seq, we observed that knock-out of lamin A/C in B cells alters EBV gene expression. Our data indicate that the interaction between lamins and the EBV episome contributes to the epigenetic control of viral gene expression during latency, suggesting a restrictive function of the nuclear lamina as part of the host response against viral DNA entry into the nucleus. Epstein-Barr virus (EBV) is a common herpesvirus that establishes a lifelong latent infection in a small fraction of B cells of the infected individuals. In most cases, EBV infection is asymptomatic; however, especially in the context of immune suppression, EBV latent infection is associated with several malignancies. In EBV+ cancer cells, latent viral gene expression plays an essential role in sustaining the cancer phenotype. We and others have established that epigenetic modifications of the viral genome are critical to regulating EBV gene expression during latency. Understanding how the EBV genome is epigenetically regulated during latent infection may help identify new specific therapeutic targets for treating EBV+ malignancies. The nuclear lamina is involved in regulating the composition and structure of the cellular chromatin. In the present study, we determined that the nuclear lamina binds the EBV genome during latency, influencing viral gene expression. Depleting one component of the nuclear lamina, lamin A/C, increased the expression of latent EBV genes associated with cellular proliferation, indicating that the binding of the nuclear lamina with the viral genome is essential to control viral gene expression in infected cells. Our data show for the first time that the nuclear lamina may be involved in the cellular response against EBV infection by restricting viral gene expression.
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Affiliation(s)
| | - Rui Guo
- Division of Infectious Diseases, Brigham & Women's Hospital, Boston, Massachusetts, United States of America.,Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America.,Broad Institute of Harvard and MIT, Cambridge, Massachusetts, United States of America
| | - Kelsey Keith
- The Coriell Institute for Medical Research, Camden, New Jersey, United States of America
| | - Jozef Madzo
- The Coriell Institute for Medical Research, Camden, New Jersey, United States of America
| | - Davide Maestri
- The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Sarah Boyle
- The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Jason Wasserman
- The Fels Cancer Institute for Personalized Medicine, School of Medicine Temple University, Philadelphia, Pennsylvania, United States of America
| | - Andrew Kossenkov
- The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Benjamin E Gewurz
- Division of Infectious Diseases, Brigham & Women's Hospital, Boston, Massachusetts, United States of America.,Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America.,Broad Institute of Harvard and MIT, Cambridge, Massachusetts, United States of America
| | - Italo Tempera
- The Wistar Institute, Philadelphia, Pennsylvania, United States of America
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8
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Molecular Basis of Epstein-Barr Virus Latency Establishment and Lytic Reactivation. Viruses 2021; 13:v13122344. [PMID: 34960613 PMCID: PMC8706188 DOI: 10.3390/v13122344] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/20/2021] [Accepted: 11/22/2021] [Indexed: 12/27/2022] Open
Abstract
Epstein–Barr virus (EBV) is a causative agent of infectious mononucleosis and several types of cancer. Like other herpesviruses, it establishes an asymptomatic, life-long latent infection, with occasional reactivation and shedding of progeny viruses. During latency, EBV expresses a small number of viral genes, and exists as an episome in the host–cell nucleus. Expression patterns of latency genes are dependent on the cell type, time after infection, and milieu of the cell (e.g., germinal center or peripheral blood). Upon lytic induction, expression of the viral immediate-early genes, BZLF1 and BRLF1, are induced, followed by early gene expression, viral DNA replication, late gene expression, and maturation and egress of progeny virions. Furthermore, EBV reactivation involves more than just progeny production. The EBV life cycle is regulated by signal transduction, transcription factors, promoter sequences, epigenetics, and the 3D structure of the genome. In this article, the molecular basis of EBV latency establishment and reactivation is summarized.
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9
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Epstein-Barr Virus Episome Physically Interacts with Active Regions of the Host Genome in Lymphoblastoid Cells. J Virol 2020; 94:JVI.01390-20. [PMID: 32999023 DOI: 10.1128/jvi.01390-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/22/2020] [Indexed: 12/22/2022] Open
Abstract
The Epstein-Barr virus (EBV) episome is known to interact with the three-dimensional structure of the human genome in infected cells. However, the exact locations of these interactions and their potential functional consequences remain unclear. Recently, high-resolution chromatin conformation capture (Hi-C) assays in lymphoblastoid cells have become available, enabling us to precisely map the contacts between the EBV episome(s) and the human host genome. Using available Hi-C data at a 10-kb resolution, we have identified 15,000 reproducible contacts between EBV episome(s) and the human genome. These contacts are highly enriched in chromatin regions denoted by typical or super enhancers and active markers, including histone H3K27ac and H3K4me1. Additionally, these contacts are highly enriched at loci bound by host transcription factors that regulate B cell growth (e.g., IKZF1 and RUNX3), factors that enhance cell proliferation (e.g., HDGF), or factors that promote viral replication (e.g., NBS1 and NFIC). EBV contacts show nearly 2-fold enrichment in host regions bound by EBV nuclear antigen 2 (EBNA2) and EBNA3 transcription factors. Circular chromosome conformation capture followed by sequencing (4C-seq) using the EBV origin of plasmid replication (oriP) as a "bait" in lymphoblastoid cells further confirmed contacts with active chromatin regions. Collectively, our analysis supports interactions between EBV episome(s) and active regions of the human genome in lymphoblastoid cells.IMPORTANCE EBV is associated with ∼200,000 cancers each year. In vitro, EBV can transform primary human B lymphocytes into immortalized cell lines. EBV-encoded proteins, along with noncoding RNAs and microRNAs, hijack cellular proteins and pathways to control cell growth. EBV nuclear proteins usurp normal transcriptional programs to activate the expression of key oncogenes, including MYC, to provide a proliferation signal. EBV nuclear antigens also repress CDKN2A to suppress senescence. EBV membrane protein activates NF-κB to provide survival signals. EBV genomes are maintained by EBNA1, which tethers EBV episomes to the host chromosomes during mitosis. However, little is known about where EBV episomes are located in interphase cells. In interphase cells, EBV promoters drive the expression of latency genes, while oriP functions as an enhancer for these promoters. In this study, integrative analyses of published lymphoblastoid cell line (LCL) Hi-C data and our 4C-seq experiments position EBV episomes to host genomes with active epigenetic marks. These contact points were significantly enriched for super enhancers. The close proximity of EBV episomes and the super enhancers that are enriched for transcription cofactors or mediators in lymphoblasts may benefit EBV gene expression, suggesting a novel mechanism of transcriptional activation.
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10
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Bojagora A, Saridakis V. USP7 manipulation by viral proteins. Virus Res 2020; 286:198076. [DOI: 10.1016/j.virusres.2020.198076] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 05/14/2020] [Accepted: 06/24/2020] [Indexed: 01/27/2023]
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11
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Guo R, Jiang C, Zhang Y, Govande A, Trudeau SJ, Chen F, Fry CJ, Puri R, Wolinsky E, Schineller M, Frost TC, Gebre M, Zhao B, Giulino-Roth L, Doench JG, Teng M, Gewurz BE. MYC Controls the Epstein-Barr Virus Lytic Switch. Mol Cell 2020; 78:653-669.e8. [PMID: 32315601 DOI: 10.1016/j.molcel.2020.03.025] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/14/2020] [Accepted: 03/16/2020] [Indexed: 12/12/2022]
Abstract
Epstein-Barr virus (EBV) is associated with multiple human malignancies. To evade immune detection, EBV switches between latent and lytic programs. How viral latency is maintained in tumors or in memory B cells, the reservoir for lifelong EBV infection, remains incompletely understood. To gain insights, we performed a human genome-wide CRISPR/Cas9 screen in Burkitt lymphoma B cells. Our analyses identified a network of host factors that repress lytic reactivation, centered on the transcription factor MYC, including cohesins, FACT, STAGA, and Mediator. Depletion of MYC or factors important for MYC expression reactivated the lytic cycle, including in Burkitt xenografts. MYC bound the EBV genome origin of lytic replication and suppressed its looping to the lytic cycle initiator BZLF1 promoter. Notably, MYC abundance decreases with plasma cell differentiation, a key lytic reactivation trigger. Our results suggest that EBV senses MYC abundance as a readout of B cell state and highlights Burkitt latency reversal therapeutic targets.
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Affiliation(s)
- Rui Guo
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Chang Jiang
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Yuchen Zhang
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Apurva Govande
- Harvard Graduate Program in Virology, Boston, MA 02115, USA
| | - Stephen J Trudeau
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Fang Chen
- Cell Signaling Technology, Inc., Danvers, MA 01923, USA
| | | | - Rishi Puri
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Emma Wolinsky
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Molly Schineller
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Thomas C Frost
- Harvard Graduate Program in Virology, Boston, MA 02115, USA
| | - Makda Gebre
- Harvard Graduate Program in Virology, Boston, MA 02115, USA
| | - Bo Zhao
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Lisa Giulino-Roth
- Division of Pediatric Hematology/Oncology, Weill Cornell Medical College, New York, NY 10065, USA
| | - John G Doench
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Mingxiang Teng
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA.
| | - Benjamin E Gewurz
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Harvard Graduate Program in Virology, Boston, MA 02115, USA.
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12
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Fernandes Q, Gupta I, Vranic S, Al Moustafa AE. Human Papillomaviruses and Epstein-Barr Virus Interactions in Colorectal Cancer: A Brief Review. Pathogens 2020; 9:pathogens9040300. [PMID: 32325943 PMCID: PMC7238043 DOI: 10.3390/pathogens9040300] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/05/2020] [Accepted: 04/07/2020] [Indexed: 02/06/2023] Open
Abstract
Human papillomaviruses (HPVs) and the Epstein-Barr virus (EBV) are the most common oncoviruses, contributing to approximately 10%-15% of all malignancies. Oncoproteins of high-risk HPVs (E5 and E6/E7), as well as EBV (LMP1, LMP2A and EBNA1), play a principal role in the onset and progression of several human carcinomas, including head and neck, cervical and colorectal. Oncoproteins of high-risk HPVs and EBV can cooperate to initiate and/or enhance epithelial-mesenchymal transition (EMT) events, which represents one of the hallmarks of cancer progression and metastasis. Although the role of these oncoviruses in several cancers is well established, their role in the pathogenesis of colorectal cancer is still nascent. This review presents an overview of the most recent advances related to the presence and role of high-risk HPVs and EBV in colorectal cancer, with an emphasis on their cooperation in colorectal carcinogenesis.
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Affiliation(s)
- Queenie Fernandes
- College of Medicine, QU Health, Qatar University, Doha 2713, Qatar; (Q.F.); (I.G.)
- Biomedical Research Centre, Qatar University, Doha 2713, Qatar
| | - Ishita Gupta
- College of Medicine, QU Health, Qatar University, Doha 2713, Qatar; (Q.F.); (I.G.)
- Biomedical Research Centre, Qatar University, Doha 2713, Qatar
| | - Semir Vranic
- College of Medicine, QU Health, Qatar University, Doha 2713, Qatar; (Q.F.); (I.G.)
- Correspondence: (S.V.); (A.-E.A.M.); Tel.:+974-4403-7873 (S.V.); +974-4403-7817 (A.-E.A.M.)
| | - Ala-Eddin Al Moustafa
- College of Medicine, QU Health, Qatar University, Doha 2713, Qatar; (Q.F.); (I.G.)
- Biomedical Research Centre, Qatar University, Doha 2713, Qatar
- Correspondence: (S.V.); (A.-E.A.M.); Tel.:+974-4403-7873 (S.V.); +974-4403-7817 (A.-E.A.M.)
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13
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Buschle A, Hammerschmidt W. Epigenetic lifestyle of Epstein-Barr virus. Semin Immunopathol 2020; 42:131-142. [PMID: 32232535 PMCID: PMC7174264 DOI: 10.1007/s00281-020-00792-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 02/14/2020] [Indexed: 12/13/2022]
Abstract
Epstein-Barr virus (EBV) is a model of herpesvirus latency and epigenetic changes. The virus preferentially infects human B-lymphocytes (and also other cell types) but does not turn them straight into virus factories. Instead, it establishes a strictly latent infection in them and concomitantly induces the activation and proliferation of infected B cells. How the virus establishes latency in its target cells is only partially understood, but its latent state has been studied intensively by many. During latency, several copies of the viral genome are maintained as minichromosomes in the nucleus. In latently infected cells, most viral genes are epigenetically repressed by cellular chromatin constituents and DNA methylation, but certain EBV genes are spared and remain expressed to support the latent state of the virus in its host cell. Latency is not a dead end, but the virus can escape from this state and reactivate. Reactivation is a coordinated process that requires the removal of repressive chromatin components and a gain in accessibility for viral and cellular factors and machines to support the entire transcriptional program of EBV's ensuing lytic phase. We have a detailed picture of the initiating events of EBV's lytic phase, which are orchestrated by a single viral protein - BZLF1. Its induced expression can lead to the expression of all lytic viral proteins, but initially it fosters the non-licensed amplification of viral DNA that is incorporated into preformed capsids. In the virions, the viral DNA is free of histones and lacks methylated cytosine residues which are lost during lytic DNA amplification. This review provides an overview of EBV's dynamic epigenetic changes, which are an integral part of its ingenious lifestyle in human host cells.
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Affiliation(s)
- Alexander Buschle
- Research Unit Gene Vectors, Helmholtz Zentrum München, German Research Center for Environmental Health and German Centre for Infection Research (DZIF), Partner site Munich, Marchioninistr. 25, D-81377, Munich, Germany
| | - Wolfgang Hammerschmidt
- Research Unit Gene Vectors, Helmholtz Zentrum München, German Research Center for Environmental Health and German Centre for Infection Research (DZIF), Partner site Munich, Marchioninistr. 25, D-81377, Munich, Germany.
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14
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Protein inhibitor of activated STAT1 (PIAS1) inhibits IRF8 activation of Epstein-Barr virus lytic gene expression. Virology 2019; 540:75-87. [PMID: 31743858 DOI: 10.1016/j.virol.2019.11.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 11/08/2019] [Accepted: 11/09/2019] [Indexed: 11/23/2022]
Abstract
Epstein-Barr virus (EBV), a major human oncogenic pathogen, establishes life-long persistent infections. In latently infected B lymphocytes, the virus persists as an episome in the nucleus. Periodic reactivation of latent virus is controlled by both viral and cellular factors. Our recent studies showed that interferon regulatory factor 8 (IRF8) is required for EBV lytic reactivation while protein inhibitor of activated STAT1 (PIAS1) functions as an EBV restriction factor to block viral reactivation. Here, we show that IRF8 directly binds to the EBV genome and regulates EBV lytic gene expression together with PU.1 and EBV transactivator RTA. Furthermore, our study reveals that PIAS1 antagonizes IRF8/PU.1-mediated lytic gene activation through binding to and inhibiting IRF8. Together, our study establishes IRF8 as a transcriptional activator in promoting EBV reactivation and defines PIAS1 as an inhibitor of IRF8 to limit lytic gene expression.
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15
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Chakravorty S, Yan B, Wang C, Wang L, Quaid JT, Lin CF, Briggs SD, Majumder J, Canaria DA, Chauss D, Chopra G, Olson MR, Zhao B, Afzali B, Kazemian M. Integrated Pan-Cancer Map of EBV-Associated Neoplasms Reveals Functional Host-Virus Interactions. Cancer Res 2019; 79:6010-6023. [PMID: 31481499 DOI: 10.1158/0008-5472.can-19-0615] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 06/24/2019] [Accepted: 08/27/2019] [Indexed: 12/20/2022]
Abstract
Epstein-Barr virus (EBV) is a complex oncogenic symbiont. The molecular mechanisms governing EBV carcinogenesis remain elusive and the functional interactions between virus and host cells are incompletely defined. Here we present a comprehensive map of the host cell-pathogen interactome in EBV-associated cancers. We systematically analyzed RNA sequencing from >1,000 patients with 15 different cancer types, comparing virus and host factors of EBV+ to EBV- tissues. EBV preferentially integrated at highly accessible regions of the cancer genome, with significant enrichment in super-enhancer architecture. Twelve EBV transcripts, including LMP1 and LMP2, correlated inversely with EBV reactivation signature. Overexpression of these genes significantly suppressed viral reactivation, consistent with a "virostatic" function. In cancer samples, hundreds of novel frequent missense and nonsense variations in virostatic genes were identified, and variant genes failed to regulate their viral and cellular targets in cancer. For example, one-third of patients with EBV+ NK/T-cell lymphoma carried two novel nonsense variants (Q322X, G342X) of LMP1 and both variant proteins failed to restrict viral reactivation, confirming loss of virostatic function. Host cell transcriptional changes in response to EBV infection classified tumors into two molecular subtypes based on patterns of IFN signature genes and immune checkpoint markers, such as PD-L1 and IDO1. Overall, these findings uncover novel points of interaction between a common oncovirus and the human genome and identify novel regulatory nodes and druggable targets for individualized EBV and cancer-specific therapies. SIGNIFICANCE: This study provides a comprehensive map of the host cell-pathogen interactome in EBV+ malignancies.See related commentary by Mbulaiteye and Prokunina-Olsson, p. 5917.
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Affiliation(s)
| | - Bingyu Yan
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Chong Wang
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Luopin Wang
- Department of Computer Science, Purdue University, West Lafayette, Indiana
| | | | - Chin Fang Lin
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, Indiana
| | - Scott D Briggs
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Joydeb Majumder
- Department of Chemistry, Purdue University, West Lafayette, Indiana
| | - D Alejandro Canaria
- Department of Biological Science, Purdue University, West Lafayette, Indiana
| | - Daniel Chauss
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland
| | - Gaurav Chopra
- Department of Chemistry, Purdue University, West Lafayette, Indiana
| | - Matthew R Olson
- Department of Biological Science, Purdue University, West Lafayette, Indiana
| | - Bo Zhao
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Behdad Afzali
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland
| | - Majid Kazemian
- Department of Biochemistry, Purdue University, West Lafayette, Indiana. .,Department of Computer Science, Purdue University, West Lafayette, Indiana
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16
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Barros SP, Hefni E, Nepomuceno R, Offenbacher S, North K. Targeting epigenetic mechanisms in periodontal diseases. Periodontol 2000 2019; 78:174-184. [PMID: 30198133 DOI: 10.1111/prd.12231] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Epigenetic factors are heritable genome modifications that potentially impact gene transcription, contributing to disease states. Epigenetic marks play an important role in chronic inflammatory conditions, as observed in periodontal diseases, by allowing microbial persistence or by permitting microbial insult to play a role in the so-called 'hit-and-run' infectious mechanism, leading to lasting pathogen interference with the host genome. Epigenetics also affects the health sciences by providing a dynamic mechanistic framework to explain the way in which environmental and behavioral factors interact with the genome to alter disease risk. In this article we review current knowledge of epigenome regulation in light of the multifactorial nature of periodontal diseases. We discuss epigenetic tagging in identified genes, and consider the potential implications of epigenetic changes on host-microbiome dynamics in chronic inflammatory states and in response to environmental stressors. The most recent advances in genomic technologies have placed us in a position to analyze interaction effects (eg, between periodontal disease and type 2 diabetes mellitus), which can be investigated through epigenome-wide association analysis. Finally, because of the individualized traits of epigenetic biomarkers, pharmacoepigenomic perspectives are also considered as potentially novel therapeutic approaches for improving periodontal disease status.
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Affiliation(s)
- Silvana P Barros
- Department of Periodontology, University of North Carolina, Chapel Hil, NC, USA
| | - Eman Hefni
- Department of Periodontology, School of Dentistry, Umm Al Qura University, Makkah, Saudi Arabia
| | - Rafael Nepomuceno
- Department of Periodontology, University of North Carolina, Chapel Hil, NC, USA
| | - Steven Offenbacher
- Department of Periodontology, University of North Carolina, Chapel Hil, NC, USA
| | - Kari North
- Department of Epidemiology and Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, NC, USA
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17
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Elevated SUV39H2 attributes to the progression of nasopharyngeal carcinoma via regulation of NRIP1. Biochem Biophys Res Commun 2019; 510:290-295. [PMID: 30709585 DOI: 10.1016/j.bbrc.2019.01.092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 01/18/2019] [Indexed: 01/02/2023]
Abstract
Nasopharyngeal carcinoma (NPC) is a prevalent tumor in southern China and southeast Asia. Recent studies have demonstrated that viral infection, somatic genetic changes, and epigenetic changes synergistically contribute to NPC pathogenesis. Genome-wide studies show that epigenetic aberrations likely drive nasopharyngeal carcinoma development and progression. This work is aimed at investigating the effect of histone methyltransferase SUV39H2 in NPC. The elevated expression of SUV39H2 in NPC is observed by analyzing GSE53819 and GSE12452 downloaded from the Gene Expression Omnibus (GEO) database. SUV39H2 knockdown inhibits NPC proliferation and induces the apoptosis of cancer cells. At last, RNaseq analysis identifies a variety of SUV39H2 downstream genes related with cancer, in which, NRIP1 is identified as a critical downstream target of SUV39H2 in NPC. Taken together, these findings provide a theoretical basis for understating the biological roles of SUV39H2 in NPC.
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18
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Ismail AM, Lee JS, Lee JY, Singh G, Dyer DW, Seto D, Chodosh J, Rajaiya J. Adenoviromics: Mining the Human Adenovirus Species D Genome. Front Microbiol 2018; 9:2178. [PMID: 30254627 PMCID: PMC6141750 DOI: 10.3389/fmicb.2018.02178] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 08/24/2018] [Indexed: 12/19/2022] Open
Abstract
Human adenovirus (HAdV) infections cause disease world-wide. Whole genome sequencing has now distinguished 90 distinct genotypes in 7 species (A-G). Over half of these 90 HAdVs fall within species D, with essentially all of the HAdV-D whole genome sequences generated in the last decade. Herein, we describe recent new findings made possible by mining of this expanded genome database, and propose future directions to elucidate new functional elements and new functions for previously known viral components.
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Affiliation(s)
- Ashrafali M Ismail
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Ji Sun Lee
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Jeong Yoon Lee
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States.,Molecular Virology Laboratory, Korea Zoonosis Research Institute, Jeonbuk National University, Jeonju, South Korea
| | - Gurdeep Singh
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - David W Dyer
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Donald Seto
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VI, United States
| | - James Chodosh
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Jaya Rajaiya
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
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19
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PARP1 Stabilizes CTCF Binding and Chromatin Structure To Maintain Epstein-Barr Virus Latency Type. J Virol 2018; 92:JVI.00755-18. [PMID: 29976663 PMCID: PMC6146685 DOI: 10.1128/jvi.00755-18] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/26/2018] [Indexed: 12/14/2022] Open
Abstract
EBV is a human gammaherpesvirus that infects more than 95% of individuals worldwide. Upon infection, EBV circularizes as an episome and establishes a chronic, latent infection in B cells. In doing so, the virus utilizes host cell machinery to regulate and maintain the viral genome. In otherwise healthy individuals, EBV infection is typically nonpathological; however, latent infection is potentially oncogenic and is responsible for 1% of human cancers. During latent infection, EBV expresses specific sets of proteins according to the given latency type, each of which is associated with specific types of cancers. For example, type III latency, in which the virus expresses its full repertoire of latent proteins, is characteristic of AIDS-associated and posttransplant lymphomas associated with EBV infection. Understanding how viral latency type is regulated at the chromatin level may reveal potential targets for EBV-specific pharmacological intervention in EBV-associated cancers. Epstein Barr virus (EBV) is a potentially oncogenic gammaherpesvirus that establishes a chronic, latent infection in memory B cells. The EBV genome persists in infected host cells as a chromatinized episome and is subject to chromatin-mediated regulation. Binding of the host insulator protein CTCF to the EBV genome has an established role in maintaining viral latency type. CTCF is posttranslationally modified by the host enzyme PARP1. PARP1, or poly(ADP-ribose) polymerase 1, catalyzes the transfer of a poly(ADP-ribose) (PAR) moiety from NAD+ onto acceptor proteins, including itself, histone proteins, and CTCF. PARylation of CTCF by PARP1 can affect CTCF's insulator activity, DNA binding capacity, and ability to form chromatin loops. Both PARP1 and CTCF have been implicated in the regulation of EBV latency and lytic reactivation. Thus, we predicted that pharmacological inhibition with PARP1 inhibitors would affect EBV latency type through a chromatin-specific mechanism. Here, we show that PARP1 and CTCF colocalize at specific sites throughout the EBV genome and provide evidence to suggest that PARP1 acts to stabilize CTCF binding and maintain the open chromatin landscape at the active Cp promoter during type III latency. Further, PARP1 activity is important in maintaining latency type-specific viral gene expression. The data presented here provide a rationale for the use of PARP inhibitors in the treatment of EBV-associated cancers exhibiting type III latency and ultimately could contribute to an EBV-specific treatment strategy for AIDS-related or posttransplant lymphomas. IMPORTANCE EBV is a human gammaherpesvirus that infects more than 95% of individuals worldwide. Upon infection, EBV circularizes as an episome and establishes a chronic, latent infection in B cells. In doing so, the virus utilizes host cell machinery to regulate and maintain the viral genome. In otherwise healthy individuals, EBV infection is typically nonpathological; however, latent infection is potentially oncogenic and is responsible for 1% of human cancers. During latent infection, EBV expresses specific sets of proteins according to the given latency type, each of which is associated with specific types of cancers. For example, type III latency, in which the virus expresses its full repertoire of latent proteins, is characteristic of AIDS-associated and posttransplant lymphomas associated with EBV infection. Understanding how viral latency type is regulated at the chromatin level may reveal potential targets for EBV-specific pharmacological intervention in EBV-associated cancers.
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20
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Almohammed R, Osborn K, Ramasubramanyan S, Perez-Fernandez IBN, Godfrey A, Mancini EJ, Sinclair AJ. Mechanism of activation of the BNLF2a immune evasion gene of Epstein-Barr virus by Zta. J Gen Virol 2018; 99:805-817. [PMID: 29580369 PMCID: PMC6096924 DOI: 10.1099/jgv.0.001056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The human gamma herpes virus Epstein–Barr virus (EBV) exploits multiple routes to evade the cellular immune response. During the EBV lytic replication cycle, viral proteins are expressed that provide excellent targets for recognition by cytotoxic T cells. This is countered by the viral BNLF2a gene. In B cells during latency, where BNLF2a is not expressed, we show that its regulatory region is embedded in repressive chromatin. The expression of BNLF2a mirrors the expression of a viral lytic cycle transcriptional regulator, Zta (BZLF1, EB1, ZEBRA), in B cells and we propose that Zta plays a role in up-regulating BNLF2a. In cells undergoing EBV lytic replication, we identified two distinct regions of interaction of Zta with the chromatin-associated BNLF2a promoter. We identify five potential Zta-response elements (ZREs) in the promoter that are highly conserved between virus isolates. Zta binds to these elements in vitro and activates the expression of the BNLF2a promoter in both epithelial and B cells. We also found redundancy amongst the ZREs. The EBV genome undergoes a biphasic DNA methylation cycle during its infection cycle. One of the ZREs contains an integral CpG motif. We show that this can be DNA methylated during EBV latency and that both Zta binding and promoter activation are enhanced by its methylation. In summary, we find that the BNLF2a promoter is directly targeted by Zta and that DNA methylation within the proximal ZRE aids activation. The implications for regulation of this key viral gene during the reactivation of EBV from latency are discussed.
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Affiliation(s)
- Rajaei Almohammed
- School of Life Sciences, University of Sussex, Brighton, East Sussex, UK.,Present address: Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Kay Osborn
- School of Life Sciences, University of Sussex, Brighton, East Sussex, UK
| | - Sharada Ramasubramanyan
- School of Life Sciences, University of Sussex, Brighton, East Sussex, UK.,Present address: RS Mehta Jain Department of Biochemistry and Cell Biology, Vision Research Foundation, Sankara Nethralaya, Chennai, India
| | | | - Anja Godfrey
- School of Life Sciences, University of Sussex, Brighton, East Sussex, UK
| | - Erika J Mancini
- School of Life Sciences, University of Sussex, Brighton, East Sussex, UK
| | - Alison J Sinclair
- School of Life Sciences, University of Sussex, Brighton, East Sussex, UK
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21
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Oncogenic Epstein-Barr virus recruits Nm23-H1 to regulate chromatin modifiers. J Transl Med 2018; 98:258-268. [PMID: 29035376 PMCID: PMC6053075 DOI: 10.1038/labinvest.2017.112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/03/2017] [Accepted: 08/16/2017] [Indexed: 12/17/2022] Open
Abstract
In cancer progression, metastasis is a major cause of poor survival of patients and can be targeted for therapeutic interventions. The first discovered metastatic-suppressor Nm23-H1 possesses nucleoside diphosphate kinase, histidine kinase, and DNase activity as a broad-spectrum enzyme. Recent advances in cancer metastasis have opened new ways for the development of therapeutic molecular approaches. In this review, we provide a summary of the current understanding of Nm23/NDPKs in the context of viral oncogenesis. We also focused on Nm23-H1-mediated cellular events with an emphasis on chromatin modifications. How Nm23-H1 modulates the activities of chromatin modifiers through interaction with Epstein-Barr virus-encoded oncogenic antigens and related crosstalks are discussed in the context of other oncogenic viruses. We also described the current understanding of the cellular and viral interactions of Nm23-H1 and their reference to transcription regulation and metastasis. Further, we summarized the recent therapeutic approaches targeting Nm23 and its potential links to pathways that can be exploited by oncogenic viruses.
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22
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Balakrishnan L, Milavetz B. Epigenetic Regulation of Viral Biological Processes. Viruses 2017; 9:v9110346. [PMID: 29149060 PMCID: PMC5707553 DOI: 10.3390/v9110346] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 11/13/2017] [Accepted: 11/15/2017] [Indexed: 12/21/2022] Open
Abstract
It is increasingly clear that DNA viruses exploit cellular epigenetic processes to control their life cycles during infection. This review will address epigenetic regulation in members of the polyomaviruses, adenoviruses, human papillomaviruses, hepatitis B, and herpes viruses. For each type of virus, what is known about the roles of DNA methylation, histone modifications, nucleosome positioning, and regulatory RNA in epigenetic regulation of the virus infection will be discussed. The mechanisms used by certain viruses to dysregulate the host cell through manipulation of epigenetic processes and the role of cellular cofactors such as BRD4 that are known to be involved in epigenetic regulation of host cell pathways will also be covered. Specifically, this review will focus on the role of epigenetic regulation in maintaining viral episomes through the generation of chromatin, temporally controlling transcription from viral genes during the course of an infection, regulating latency and the switch to a lytic infection, and global dysregulation of cellular function.
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Affiliation(s)
- Lata Balakrishnan
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA.
| | - Barry Milavetz
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58203, USA.
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23
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Funata S, Matsusaka K, Yamanaka R, Yamamoto S, Okabe A, Fukuyo M, Aburatani H, Fukayama M, Kaneda A. Histone modification alteration coordinated with acquisition of promoter DNA methylation during Epstein-Barr virus infection. Oncotarget 2017; 8:55265-55279. [PMID: 28903418 PMCID: PMC5589657 DOI: 10.18632/oncotarget.19423] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 07/11/2017] [Indexed: 12/23/2022] Open
Abstract
Aberrant DNA hypermethylation is a major epigenetic mechanism to inactivate tumor suppressor genes in cancer. Epstein-Barr virus positive gastric cancer is the most frequently hypermethylated tumor among human malignancies. Herein, we performed comprehensive analysis of epigenomic alteration during EBV infection, by Infinium HumanMethylation 450K BeadChip for DNA methylation and ChIP-sequencing for histone modification alteration during EBV infection into gastric cancer cell line MKN7. Among 7,775 genes with increased DNA methylation in promoter regions, roughly half were “DNA methylation-sensitive” genes, which acquired DNA methylation in the whole promoter regions and thus were repressed. These included anti-oncogenic genes, e.g. CDKN2A. The other half were “DNA methylation-resistant” genes, where DNA methylation is acquired in the surrounding of promoter regions, but unmethylated status is protected in the vicinity of transcription start site. These genes thereby retained gene expression, and included DNA repair genes. Histone modification was altered dynamically and coordinately with DNA methylation alteration. DNA methylation-sensitive genes significantly correlated with loss of H3K27me3 pre-marks or decrease of active histone marks, H3K4me3 and H3K27ac. Apoptosis-related genes were significantly enriched in these epigenetically repressed genes. Gain of active histone marks significantly correlated with DNA methylation-resistant genes. Genes related to mitotic cell cycle and DNA repair were significantly enriched in these epigenetically activated genes. Our data show that orchestrated epigenetic alterations are important in gene regulation during EBV infection, and histone modification status in promoter regions significantly associated with acquisition of de novo DNA methylation or protection of unmethylated status at transcription start site.
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Affiliation(s)
- Sayaka Funata
- Department of Molecular Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan.,Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Keisuke Matsusaka
- Department of Molecular Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Ryota Yamanaka
- Genome Science Division, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Shogo Yamamoto
- Genome Science Division, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Atsushi Okabe
- Department of Molecular Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Masaki Fukuyo
- Department of Molecular Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Hiroyuki Aburatani
- Genome Science Division, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Masashi Fukayama
- Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Atsushi Kaneda
- Department of Molecular Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan
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24
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Human Herpesvirus 6B Induces Hypomethylation on Chromosome 17p13.3, Correlating with Increased Gene Expression and Virus Integration. J Virol 2017; 91:JVI.02105-16. [PMID: 28298607 DOI: 10.1128/jvi.02105-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 03/03/2017] [Indexed: 12/21/2022] Open
Abstract
Human herpesvirus 6B (HHV-6B) is a neurotropic betaherpesvirus that achieves latency by integrating its genome into host cell chromosomes. Several viruses can induce epigenetic modifications in their host cells, but no study has investigated the epigenetic modifications induced by HHV-6B. This study analyzed methylation with an Illumina 450K array, comparing HHV-6B-infected and uninfected Molt-3 T cells 3 days postinfection. Bisulfite pyrosequencing was used to validate the Illumina results and to investigate methylation over time in vitro Expression of genes was investigated using quantitative PCR (qPCR), and virus integration was investigated with PCR. A total of 406 CpG sites showed a significant HHV-6B-induced change in methylation in vitro Remarkably, 86% (351/406) of these CpGs were located <1 Mb from chromosomal ends and were all hypomethylated in virus-infected cells. This was most evident at chromosome 17p13.3, where HHV-6B had induced CpG hypomethylation after 2 days of infection, possibly through TET2, which was found to be upregulated by the virus. In addition, virus-induced cytosine hydroxymethylation was observed. Genes located in the hypomethylated region at 17p13.3 showed significantly upregulated expression in HHV-6B-infected cells. A temporal experiment revealed HHV-6B integration in Molt-3 cell DNA 3 days after infection. The telomere at 17p has repeatedly been described as an integration site for HHV-6B, and we show for the first time that HHV-6B induces hypomethylation in this region during acute infection, which may play a role in the integration process, possibly by making the DNA more accessible.IMPORTANCE The ability to establish latency in the host is a hallmark of herpesviruses, but the mechanisms differ. Human herpesvirus 6B (HHV-6B) is known to establish latency through integration of its genome into the telomeric regions of host cells, with the ability to reactivate. Our study is the first to show that HHV-6B specifically induces hypomethylated regions close to the telomeres and that integrating viruses may use the host methylation machinery to facilitate their integration process. The results from this study contribute to knowledge of HHV-6B biology and virus-host interaction. This in turn will lead to further progress in our understanding of the underlying mechanisms by which HHV-6B contributes to pathological processes and may have important implications in both disease prevention and treatment.
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Lupey-Green LN, Moquin SA, Martin KA, McDevitt SM, Hulse M, Caruso LB, Pomerantz RT, Miranda JL, Tempera I. PARP1 restricts Epstein Barr Virus lytic reactivation by binding the BZLF1 promoter. Virology 2017; 507:220-230. [PMID: 28456021 PMCID: PMC5521201 DOI: 10.1016/j.virol.2017.04.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 03/14/2017] [Accepted: 04/06/2017] [Indexed: 12/12/2022]
Abstract
The Epstein Barr virus (EBV) genome persists in infected host cells as a chromatinized episome and is subject to chromatin-mediated regulation. Binding of the host insulator protein CTCF to the EBV genome has an established role in maintaining viral latency type, and in other herpesviruses, loss of CTCF binding at specific regions correlates with viral reactivation. Here, we demonstrate that binding of PARP1, an important cofactor of CTCF, at the BZLF1 lytic switch promoter restricts EBV reactivation. Knockdown of PARP1 in the Akata-EBV cell line significantly increases viral copy number and lytic protein expression. Interestingly, CTCF knockdown has no effect on viral reactivation, and CTCF binding across the EBV genome is largely unchanged following reactivation. Moreover, EBV reactivation attenuates PARP activity, and Zta expression alone is sufficient to decrease PARP activity. Here we demonstrate a restrictive function of PARP1 in EBV lytic reactivation.
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Affiliation(s)
- Lena N Lupey-Green
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Stephanie A Moquin
- Gladstone Institute of Virology and Immunology, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Kayla A Martin
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Shane M McDevitt
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Michael Hulse
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Lisa B Caruso
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Richard T Pomerantz
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Jj L Miranda
- Gladstone Institute of Virology and Immunology, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Italo Tempera
- Fels Institute for Cancer Research & Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA.
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Gibeault RL, Conn KL, Bildersheim MD, Schang LM. An Essential Viral Transcription Activator Modulates Chromatin Dynamics. PLoS Pathog 2016; 12:e1005842. [PMID: 27575707 PMCID: PMC5004865 DOI: 10.1371/journal.ppat.1005842] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 08/03/2016] [Indexed: 12/02/2022] Open
Abstract
Although ICP4 is the only essential transcription activator of herpes simplex virus 1 (HSV-1), its mechanisms of action are still only partially understood. We and others propose a model in which HSV-1 genomes are chromatinized as a cellular defense to inhibit HSV-1 transcription. To counteract silencing, HSV-1 would have evolved proteins that prevent or destabilize chromatinization to activate transcription. These proteins should act as HSV-1 transcription activators. We have shown that HSV-1 genomes are organized in highly dynamic nucleosomes and that histone dynamics increase in cells infected with wild type HSV-1. We now show that whereas HSV-1 mutants encoding no functional ICP0 or VP16 partially enhanced histone dynamics, mutants encoding no functional ICP4 did so only minimally. Transient expression of ICP4 was sufficient to enhance histone dynamics in the absence of other HSV-1 proteins or HSV-1 DNA. The dynamics of H3.1 were increased in cells expressing ICP4 to a greater extent than those of H3.3. The dynamics of H2B were increased in cells expressing ICP4, whereas those of canonical H2A were not. ICP4 preferentially targets silencing H3.1 and may also target the silencing H2A variants. In infected cells, histone dynamics were increased in the viral replication compartments, where ICP4 localizes. These results suggest a mechanism whereby ICP4 activates transcription by disrupting, or preventing the formation of, stable silencing nucleosomes on HSV-1 genomes. The nuclear-replicating DNA viruses of the family herpesviridae cause a variety of diseases. Eight herpesviruses infect humans. Three of them, including herpes simplex virus 1 (HSV-1), belong to the alpha-herpesvirus sub-family. Viruses in this family have the fastest replication cycles of all herpesviruses, producing acute symptoms. During lytic infection, the genomes of HSV-1 associate with histones in more dynamic chromatin than those of the beta- and gamma- herpesviruses. The transcription activator ICP4 is conserved only among alpha-herpesviruses. Although ICP4 is essential, relatively little is known about its mechanisms of action. We have shown that histone dynamics are enhanced in HSV-1 lytically infected cells. Here we show that HSV-1 mutants in ICP4 are deficient in their ability to enhance histone dynamics. ICP4 was sufficient to enhance histone dynamics in the absence of other HSV-1 proteins or DNA. The dynamics of histones were greater in the viral replication compartments, where ICP4 localizes, than in the cellular chromatin. ICP4 may thus mobilize histones away from HSV-1 genomes to activate transcription. Such a mechanism of transcription activation would result in the highly dynamic nature of the viral chromatin and the fast replication cycles, and the acute pathologies, of the alpha-herpesviruses.
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Affiliation(s)
- Rebecca L. Gibeault
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Kristen L. Conn
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | | | - Luis M. Schang
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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HCF1 and OCT2 Cooperate with EBNA1 To Enhance OriP-Dependent Transcription and Episome Maintenance of Latent Epstein-Barr Virus. J Virol 2016; 90:5353-5367. [PMID: 27009953 PMCID: PMC4934754 DOI: 10.1128/jvi.00239-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/11/2016] [Indexed: 12/14/2022] Open
Abstract
Epstein-Barr virus (EBV) establishes latent infections as multicopy episomes with complex patterns of viral gene transcription and chromatin structure. The EBV origin of plasmid replication (OriP) has been implicated as a critical control element for viral transcription, as well as viral DNA replication and episome maintenance. Here, we examine cellular factors that bind OriP and regulate histone modification, transcription regulation, and episome maintenance. We found that OriP is enriched for histone H3 lysine 4 (H3K4) methylation in multiple cell types and latency types. Host cell factor 1 (HCF1), a component of the mixed-lineage leukemia (MLL) histone methyltransferase complex, and transcription factor OCT2 (octamer-binding transcription factor 2) bound cooperatively with EBNA1 (Epstein-Barr virus nuclear antigen 1) at OriP. Depletion of OCT2 or HCF1 deregulated latency transcription and histone modifications at OriP, as well as the OriP-regulated latency type-dependent C promoter (Cp) and Q promoter (Qp). HCF1 depletion led to a loss of histone H3K4me3 (trimethylation of histone H3 at lysine 4) and H3 acetylation at Cp in type III latency and Qp in type I latency, as well as an increase in heterochromatic H3K9me3 at these sites. HCF1 depletion resulted in the loss of EBV episomes from Burkitt's lymphoma cells with type I latency and reactivation from lymphoblastoid cells (LCLs) with type III latency. These findings indicate that HCF1 and OCT2 function at OriP to regulate viral transcription, histone modifications, and episome maintenance. As HCF1 is best known for its function in herpes simplex virus 1 (HSV-1) immediate early gene transcription, our findings suggest that EBV latency transcription shares unexpected features with HSV gene regulation. IMPORTANCE EBV latency is associated with several human cancers. Viral latent cycle gene expression is regulated by the epigenetic control of the OriP enhancer region. Here, we show that cellular factors OCT2 and HCF1 bind OriP in association with EBNA1 to maintain elevated histone H3K4me3 and transcriptional enhancer function. HCF1 is known as a transcriptional coactivator of herpes simplex virus (HSV) immediate early (IE) transcription, suggesting that OriP enhancer shares aspects of HSV IE transcription control.
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Shi Y, Peng SL, Yang LF, Chen X, Tao YG, Cao Y. Co-infection of Epstein-Barr virus and human papillomavirus in human tumorigenesis. CHINESE JOURNAL OF CANCER 2016; 35:16. [PMID: 26801987 PMCID: PMC4724123 DOI: 10.1186/s40880-016-0079-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 08/07/2015] [Indexed: 12/17/2022]
Abstract
Viral infections contribute to approximately 12% of cancers worldwide, with the vast majority occurring in developing countries and areas. Two DNA viruses, Epstein-Barr virus (EBV) and human papillomavirus (HPV), are associated with 38% of all virus-associated cancers. The probability of one patient infected with these two distinct types of viruses is increasing. Here, we summarize the co-infection of EBV and HPV in human malignancies and address the possible mechanisms for the co-infection of EBV and HPV during tumorigenesis.
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Affiliation(s)
- Ying Shi
- Cancer Research Institute, Central South University, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis, National Health and Family Planning Commission, Changsha, 410078, Hunan, P. R. China.
| | - Song-Ling Peng
- Cancer Research Institute, Central South University, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis, National Health and Family Planning Commission, Changsha, 410078, Hunan, P. R. China.
| | - Li-Fang Yang
- Cancer Research Institute, Central South University, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis, National Health and Family Planning Commission, Changsha, 410078, Hunan, P. R. China.
| | - Xue Chen
- Cancer Research Institute, Central South University, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis, National Health and Family Planning Commission, Changsha, 410078, Hunan, P. R. China.
| | - Yong-Guang Tao
- Cancer Research Institute, Central South University, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis, National Health and Family Planning Commission, Changsha, 410078, Hunan, P. R. China.
| | - Ya Cao
- Cancer Research Institute, Central South University, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha, 410078, Hunan, P. R. China.
- Key Laboratory of Carcinogenesis, National Health and Family Planning Commission, Changsha, 410078, Hunan, P. R. China.
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Epigenetic Alterations in Epstein-Barr Virus-Associated Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 879:39-69. [DOI: 10.1007/978-3-319-24738-0_3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Abstract
DNA tumor viruses including members of the polyomavirus, adenovirus, papillomavirus, and herpes virus families are presently the subject of intense interest with respect to the role that epigenetics plays in control of the virus life cycle and the transformation of a normal cell to a cancer cell. To date, these studies have primarily focused on the role of histone modification, nucleosome location, and DNA methylation in regulating the biological consequences of infection. Using a wide variety of strategies and techniques ranging from simple ChIP to ChIP-chip and ChIP-seq to identify histone modifications, nuclease digestion to genome wide next generation sequencing to identify nucleosome location, and bisulfite treatment to MeDIP to identify DNA methylation sites, the epigenetic regulation of these viruses is slowly becoming better understood. While the viruses may differ in significant ways from each other and cellular chromatin, the role of epigenetics appears to be relatively similar. Within the viral genome nucleosomes are organized for the expression of appropriate genes with relevant histone modifications particularly histone acetylation. DNA methylation occurs as part of the typical gene silencing during latent infection by herpesviruses. In the simple tumor viruses like the polyomaviruses, adenoviruses, and papillomaviruses, transformation of the cell occurs via integration of the virus genome such that the virus's normal regulation is disrupted. This results in the unregulated expression of critical viral genes capable of redirecting cellular gene expression. The redirected cellular expression is a consequence of either indirect epigenetic regulation where cellular signaling or transcriptional dysregulation occurs or direct epigenetic regulation where epigenetic cofactors such as histone deacetylases are targeted. In the more complex herpersviruses transformation is a consequence of the expression of the viral latency proteins and RNAs which again can have either a direct or indirect effect on epigenetic regulation of cellular expression. Nevertheless, many questions still remain with respect to the specific mechanisms underlying epigenetic regulation of the viruses and transformation.
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Niller HH, Tarnai Z, Decsi G, Zsedényi A, Bánáti F, Minarovits J. Role of epigenetics in EBV regulation and pathogenesis. Future Microbiol 2015; 9:747-56. [PMID: 25046522 DOI: 10.2217/fmb.14.41] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epigenetic modifications of the viral and host cell genomes regularly occur in EBV-associated lymphomas and carcinomas. The cell type-dependent usage of latent EBV promoters is determined by the cellular epigenetic machinery. Viral oncoproteins interact with the very same epigenetic regulators and alter the cellular epigenotype and gene-expression pattern: there are common gene sets hypermethylated in both EBV-positive and EBV-negative neoplasms of different histological types. A group of hypermethylated promoters may represent, however, a unique EBV-associated epigenetic signature in EBV-positive gastric carcinomas. By contrast, EBV-immortalized B-lymphoblastoid cell lines are characterized by genome-wide demethylation and loss and rearrangement of heterochromatic histone marks. Early steps of EBV infection may also contribute to reprogramming of the cellular epigenome.
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Affiliation(s)
- Hans Helmut Niller
- Department of Microbiology & Hygiene, University of Regensburg, Franz-Josef-Strauss Allee 11, D-93053 Regensburg, Germany
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Tierney RJ, Nagra J, Rowe M, Bell AI, Rickinson AB. The Epstein-Barr virus BamHI C promoter is not essential for B cell immortalization in vitro, but it greatly enhances B cell growth transformation. J Virol 2015; 89:2483-93. [PMID: 25540367 PMCID: PMC4325715 DOI: 10.1128/jvi.03300-14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 12/08/2014] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Epstein-Barr virus (EBV) infection of B cells leads to the sequential activation of two viral promoters, Wp and Cp, resulting in the expression of six EBV nuclear antigens (EBNAs) and the viral Bcl2 homologue BHRF1. The viral transactivator EBNA2 is required for this switch from Wp to Cp usage during the initial stages of infection. EBNA2-dependent Cp transcription is mediated by the EBNA2 response element (E2RE), a region that contains at least two binding sites for cellular factors; one of these sites, CBF1, interacts with RBP-JK, which then recruits EBNA2 to the transcription initiation complex. Here we demonstrate that the B cell-specific transcription factor BSAP/Pax5 binds to a second site, CBF2, in the E2RE. Deletion of the E2RE in the context of a recombinant virus greatly diminished levels of Cp-initiated transcripts during the initial stages of infection but did not affect the levels of Wp-initiated transcripts or EBNA mRNAs. Consistent with this finding, viruses deleted for the E2RE were not markedly impaired in their ability to induce B cell transformation in vitro. In contrast, a larger deletion of the entire Cp region did reduce EBNA mRNA levels early after infection and subsequently almost completely ablated lymphoblastoid cell line (LCL) outgrowth. Notably, however, rare LCLs could be established following infection with Cp-deleted viruses, and these were indistinguishable from wild-type-derived LCLs in terms of steady-state EBV gene transcription. These data indicate that, unlike Wp, Cp is dispensable for the virus' growth-transforming activity. IMPORTANCE Epstein-Barr virus (EBV), a B lymphotropic herpesvirus etiologically linked to several B cell malignancies, efficiently induces B cell proliferation leading to the outgrowth of lymphoblastoid cell lines (LCLs). The initial stages of this growth-transforming infection are characterized by the sequential activation of two viral promoters, Wp and Cp, both of which appear to be preferentially active in target B cells. In this work, we have investigated the importance of Cp activity in initiating B cell proliferation and maintaining LCL growth. Using recombinant viruses, we demonstrate that while Cp is not essential for LCL outgrowth in vitro, it enhances transformation efficiency by >100-fold. We also show that Cp, like Wp, interacts with the B cell-specific activator protein BSAP/Pax5. We suggest that EBV has evolved this two-promoter system to ensure efficient colonization of the host B cell system in vivo.
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Affiliation(s)
- Rosemary J Tierney
- School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jasdeep Nagra
- School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Martin Rowe
- School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Andrew I Bell
- School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Alan B Rickinson
- School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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Abstract
EBV latent infection is characterized by a highly restricted pattern of viral gene expression. EBV can establish latent infections in multiple different tissue types with remarkable variation and plasticity in viral transcription and replication. During latency, the viral genome persists as a multi-copy episome, a non-integrated-closed circular DNA with nucleosome structure similar to cellular chromosomes. Chromatin assembly and histone modifications contribute to the regulation of viral gene expression, DNA replication, and episome persistence during latency. This review focuses on how EBV latency is regulated by chromatin and its associated processes.
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Abstract
The diversity of regulatory genetic variants and their mechanisms of action reflect the complexity and context-specificity of gene regulation. Regulatory variants are important in human disease and defining such variants and establishing mechanism is crucial to the interpretation of disease-association studies. This review describes approaches for identifying and functionally characterizing regulatory variants, illustrated using examples from common diseases. Insights from recent advances in resolving the functional epigenomic regulatory landscape in which variants act are highlighted, showing how this has enabled functional annotation of variants and the generation of hypotheses about mechanism of action. The utility of quantitative trait mapping at the transcript, protein and metabolite level to define association of specific genes with particular variants and further inform disease associations are reviewed. Establishing mechanism of action is an essential step in resolving functional regulatory variants, and this review describes how this is being facilitated by new methods for analyzing allele-specific expression, mapping chromatin interactions and advances in genome editing. Finally, integrative approaches are discussed together with examples highlighting how defining the mechanism of action of regulatory variants and identifying specific modulated genes can maximize the translational utility of genome-wide association studies to understand the pathogenesis of diseases and discover new drug targets or opportunities to repurpose existing drugs to treat them.
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Affiliation(s)
- Julian Charles Knight
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN UK
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35
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Niller HH, Szenthe K, Minarovits J. Epstein-Barr virus-host cell interactions: an epigenetic dialog? Front Genet 2014; 5:367. [PMID: 25400657 PMCID: PMC4212275 DOI: 10.3389/fgene.2014.00367] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/02/2014] [Indexed: 12/23/2022] Open
Abstract
Here, we wish to highlight the genetic exchange and epigenetic interactions between Epstein–Barr virus (EBV) and its host. EBV is associated with diverse lymphoid and epithelial malignancies. Their molecular pathogenesis is accompanied by epigenetic alterations which are distinct for each of them. While lymphoblastoid cell lines derived from B cells transformed by EBV in vitro are characterized by a massive demethylation and euchromatinization of the viral and cellular genomes, the primarily malignant lymphoid tumor Burkitt’s lymphoma and the epithelial tumors nasopharyngeal carcinoma and EBV-associated gastric carcinoma are characterized by hypermethylation of a multitude of cellular tumor suppressor gene loci and of the viral genomes. In some cases, the viral latency and oncoproteins including the latent membrane proteins LMP1 and LMP2A and several nuclear antigens affect the level of cellular DNA methyltransferases or interact with the histone modifying machinery. Specific molecular mechanisms of the epigenetic dialog between virus and host cell remain to be elucidated.
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Affiliation(s)
- Hans H Niller
- Institute of Medical Microbiology and Hygiene, University of Regensburg , Regensburg, Germany
| | - Kalman Szenthe
- RT-Europe Nonprofit Research Ltd, Mosonmagyaróvár , Hungary
| | - Janos Minarovits
- Department of Oral Biology and Experimental Dental Research, Faculty of Dentistry, University of Szeged , Szeged, Hungary
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Mortazavi H, Baharvand M, Movahhedian A, Mohammadi M, Khodadoustan A. Xerostomia due to systemic disease: a review of 20 conditions and mechanisms. Ann Med Health Sci Res 2014; 4:503-10. [PMID: 25221694 PMCID: PMC4160670 DOI: 10.4103/2141-9248.139284] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Xerostomia is a common complaint of nearly half of the elderly population and about one-fifth of younger adults. It causes several signs and symptoms, and compromise oral functions and health-related quality-of-life. Multiple reasons are proposed to describe the etiology of xerostomia such as local factors, psychogenic factors, and systemic diseases. In order to manage xerostomia effectively, identification of the main causality is mandatory. The aim of this review was to present systemic diseases leading to xerostomia with their mechanisms of action. We used various general search engines and specialized databases such as Google, Google Scholar, Yahoo, PubMed, PubMed Central, MedLine Plus, Medknow, EBSCO, ScienceDirect, Scopus, WebMD, EMBASE, and authorized textbooks to find relevant topics by means of Medical Subject Headings keywords such as "xerostomia," "hyposalivations," "mouth dryness," "disease," and "systemic." We appraised 97 English-language articles published over the last 40 years in both medical and dental journals including reviews, meta-analysis, original papers, and case reports. Upon compilation of relevant data, it was concluded that autoimmune diseases most frequently involve salivary glands and cause xerostomia followed by diabetes mellitus, renal failure, and graft-versus-host disease. Moreover, the underlying mechanisms of systemic disease-related xerostomia are: autoimmunity, infiltration of immunocompetent cells, granuloma formation, fibrosis and dehydration, deposition of proteinaceous substances, bacterial infection, and side-effects of medications.
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Affiliation(s)
- H Mortazavi
- Department of Oral and Maxillofacial Medicine, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - M Baharvand
- Department of Oral and Maxillofacial Medicine, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - A Movahhedian
- Dental Student, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - M Mohammadi
- Dental Student, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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37
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Bordi I, Ricigliano VAG, Umeton R, Ristori G, Grassi F, Crisanti A, Sutera A, Salvetti M. Noise in multiple sclerosis: unwanted and necessary. Ann Clin Transl Neurol 2014; 1:502-11. [PMID: 25356421 PMCID: PMC4184780 DOI: 10.1002/acn3.72] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/12/2014] [Accepted: 05/17/2014] [Indexed: 12/25/2022] Open
Abstract
As our knowledge about the etiology of multiple sclerosis (MS) increases, deterministic paradigms appear insufficient to describe the pathogenesis of the disease, and the impression is that stochastic phenomena (i.e. random events not necessarily resulting in disease in all individuals) may contribute to the development of MS. However, sources and mechanisms of stochastic behavior have not been investigated and there is no proposed framework to incorporate nondeterministic processes into disease biology. In this report, we will first describe analogies between physics of nonlinear systems and cell biology, showing how small-scale random perturbations can impact on large-scale phenomena, including cell function. We will then review growing and solid evidence showing that stochastic gene expression (or gene expression “noise”) can be a driver of phenotypic variation. Moreover, we will describe new methods that open unprecedented opportunities for the study of such phenomena in patients and the impact of this information on our understanding of MS course and therapy.
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Affiliation(s)
- Isabella Bordi
- Department of Physics, Sapienza University of Rome Rome, Italy
| | - Vito A G Ricigliano
- Neurology and Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), Centre for Experimental Neurological Therapies (CENTERS), Sapienza University of Rome Rome, Italy ; Neuroimmunology Unit, Fondazione Santa Lucia, (I.R.C.C.S.) Rome, Italy
| | - Renato Umeton
- Neurology and Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), Centre for Experimental Neurological Therapies (CENTERS), Sapienza University of Rome Rome, Italy
| | - Giovanni Ristori
- Neurology and Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), Centre for Experimental Neurological Therapies (CENTERS), Sapienza University of Rome Rome, Italy
| | - Francesca Grassi
- Department of Physiology and Pharmacology, Sapienza University of Rome Rome, Italy
| | - Andrea Crisanti
- Department of Physics, Sapienza University of Rome Rome, Italy
| | - Alfonso Sutera
- Department of Physics, Sapienza University of Rome Rome, Italy
| | - Marco Salvetti
- Neurology and Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), Centre for Experimental Neurological Therapies (CENTERS), Sapienza University of Rome Rome, Italy
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Tempera I, Lieberman PM. Epigenetic regulation of EBV persistence and oncogenesis. Semin Cancer Biol 2014; 26:22-9. [PMID: 24468737 DOI: 10.1016/j.semcancer.2014.01.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 12/30/2013] [Accepted: 01/09/2014] [Indexed: 12/29/2022]
Abstract
Epigenetic mechanisms play a fundamental role in generating diverse and heritable patterns of viral and cellular gene expression. Epstein-Barr virus (EBV) can adopt a variety of gene expression programs that are necessary for long-term viral persistence and latency in multiple host-cell types and conditions. The latent viral genomes assemble into chromatin structures with different histone and DNA modifications patterns that control viral gene expression. Variations in nucleosome organization and chromatin conformations can also influence gene expression by coordinating physical interactions between different regulatory elements. The viral-encoded and host-cell factors that control these epigenetic features are beginning to be understood at the genome-wide level. These epigenetic regulators can also influence viral pathogenesis by expanding tissue tropism, evading immune detection, and driving host-cell carcinogenesis. Here, we review some of the recent findings and perspectives on how the EBV epigenome plays a central role in viral latency and viral-associated carcinogenesis.
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Affiliation(s)
- Italo Tempera
- The Fels Institute, Department of Microbiology and Immunology, Temple School of Medicine, Philadelphia, PA 19140, United States.
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Catez F, Rousseau A, Labetoulle M, Lomonte P. Detection of the genome and transcripts of a persistent DNA virus in neuronal tissues by fluorescent in situ hybridization combined with immunostaining. J Vis Exp 2014:e51091. [PMID: 24514006 DOI: 10.3791/51091] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Single cell codetection of a gene, its RNA product and cellular regulatory proteins is critical to study gene expression regulation. This is a challenge in the field of virology; in particular for nuclear-replicating persistent DNA viruses that involve animal models for their study. Herpes simplex virus type 1 (HSV-1) establishes a life-long latent infection in peripheral neurons. Latent virus serves as reservoir, from which it reactivates and induces a new herpetic episode. The cell biology of HSV-1 latency remains poorly understood, in part due to the lack of methods to detect HSV-1 genomes in situ in animal models. We describe a DNA-fluorescent in situ hybridization (FISH) approach efficiently detecting low-copy viral genomes within sections of neuronal tissues from infected animal models. The method relies on heat-based antigen unmasking, and directly labeled home-made DNA probes, or commercially available probes. We developed a triple staining approach, combining DNA-FISH with RNA-FISH and immunofluorescence, using peroxidase based signal amplification to accommodate each staining requirement. A major improvement is the ability to obtain, within 10 µm tissue sections, low-background signals that can be imaged at high resolution by confocal microscopy and wide-field conventional epifluorescence. Additionally, the triple staining worked with a wide range of antibodies directed against cellular and viral proteins. The complete protocol takes 2.5 days to accommodate antibody and probe penetration within the tissue.
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Affiliation(s)
- Frédéric Catez
- Virus and Centromere Team, Centre de Génétique et Physiologie Moléculaire et Cellulaire, CNRS UMR 5534
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Abstract
The human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) establish long-term latent infections associated with diverse human cancers. Viral oncogenesis depends on the ability of the latent viral genome to persist in host nuclei as episomes that express a restricted yet dynamic pattern of viral genes. Multiple epigenetic events control viral episome generation and maintenance. This Review highlights some of the recent findings on the role of chromatin assembly, histone and DNA modifications, and higher-order chromosome structures that enable gammaherpesviruses to establish stable latent infections that mediate viral pathogenesis.
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