Genomic-scale identification of host genes regulated by EBV during lytic cycle [ChIP-Seq]
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE58245 | GEO | 2015/03/18
SECONDARY ACCESSION(S): PRJNA251726
REPOSITORIES: GEO
Similar Datasets
Project description:Infection of resting primary B-lymphocytes by Epstein Barr virus (EBV) generates a population of cells that are effectively immortal. This represents the first step in the establishment of life-long viral latency in vivo and generates precursors that can develop into the lymphoid malignancies. However, virus spread requires a switch from latency to the lytic replication cycle, a process orchestrated by the virally encoded protein Zta, an AP1-like transcription factor that interacts with a 7 base-pair DNA sequence element. As Zta has the potential to reprogram the patterns of gene expression in the host cell, we undertook global transcriptome analyses (RNA sequencing) in a Burkitts lymphoma derived cell line in which the Zta is expressed from an inducible promoter, mimicking the switch from latency to lytic cycle. We identified 2,263 host genes whose expression levels were altered. In parallel, we performed chromatin precipitation and next-generation DNA sequencing (ChIP-Seq) to identify genes that are direct targets of Zta. Integrating these data sets revealed 277 host genes that appear to be directly regulated by Zta. Surprisingly, the frequency and distribution of the Zta binding peaks suggests that Zta regulates host genes through long-range enhancers, with a median distance of 25.8kb from the transcriptional start site, rather than equivalents of the promoter elements through which Zta regulates viral genes.
2015-03-18 | GSE57732 | GEO
Project description:The human gamma herpesvirus Epstein-Barr virus, infects most adults and is an important contributor to the development of many types of cancer. Essential contributions of viral genes to replication are known but the potential contributions of cell genes to viral replication are less well delineated. A key player is the viral protein Zta (BZLF1, ZEBRA, Z). This sequence-specific DNA-binding protein can disrupt viral latency by driving the transcription of target genes and by interacting with the EBV lytic origin of replication. Here we used an unbiased approach to identify the Zta-interactome in cells derived from a Burkitt’s lymphoma. Isolating Zta and associated proteins from Burkitt’s lymphoma cells undergoing EBV replication, followed by Tandem Mass Tag (TMT) mass spectrometry resulted in the identification of forty-four viral and cellular proteins in the Zta interactome. Of these two were known targets of Zta. The association of Zta with Hsc70 and the contribution that Hsc70 plays to EBV replication mirrors a contribution from HSP70 family members to the replication of other herpesviruses. Conversely, the association of Zta with NFATc2 has no known parallels for other herpesviruses. Zta attenuates the activity of an NFAT-dependent promoter, which shows a potential for dampening the expression of genes regulated by calcium-dependent signal transduction. Indeed, Zta has the ability to affect a feed-back loop limiting its own expression, which would aid viral replication by preventing the toxic effects of Zta overexpression.
2019-06-06 | PXD013727 | Pride
Project description:Epstein-Barr virus (EBV) is present in a state of latency in infected memory B-cells and EBV-associated lymphoid and epithelial cancers. Cell stimulation or differentiation of infected B-cells and epithelial cells induces reactivation to the lytic replication cycle. In each cell type, the EBV transcription and replication factor Zta (BZLF1, EB1) plays a role in mediating the lytic cycle of EBV. Zta is a transcription factor that interacts directly with Zta response elements (ZREs) within viral and cellular genomes. Here we undertake chromatin-precipitation coupled to DNA-sequencing (ChIP-Seq) of Zta-associated DNA from cancer-derived epithelial cells. The analysis identified over 14,000 Zta-binding sites in the cellular genome. We assessed the impact of lytic cycle reactivation on changes in gene expression for a panel of Zta-associated cellular genes. Finally, we compared the Zta-binding sites identified in this study with those previously identified in B-cells and reveal substantial conservation in genes associated with Zta-binding sites.
2021-02-20 | GSE83354 | GEO
Project description:Lytic activation from latency is a key transition point in the life cycle of herpesviruses. Epstein-Barr virus (EBV) is a human herpesvirus that can cause lymphomas, epithelial cancers, and other diseases, most of which require the lytic cycle. While the lytic cycle of EBV can be triggered by chemicals and immunologic ligands, the lytic cascade is only activated when expression of the EBV latency-to-lytic switch protein ZEBRA is turned on. ZEBRA then transcriptionally activates other EBV genes and together with some of those gene products ensures completion of the lytic cycle. However, not every latently-infected cell exposed to a lytic trigger turns expression of ZEBRA on, resulting in responsive and refractory subpopulations. What governs this dichotomy? By examining the nascent transcriptome following exposure to a lytic trigger, we find that several cellular genes are transcriptionally upregulated temporally upstream of ZEBRA. These genes regulate lytic susceptibility to variable degrees in latently-infected cells that respond to mechanistically distinct lytic triggers. While increased expression of these cellular genes defines a pro-lytic state, such upregulation also runs counter to the well-known mechanism of viral nuclease-mediated host shut-off that is activated downstream of ZEBRA. Furthermore, a subset of upregulated cellular genes is transcriptionally repressed downstream of ZEBRA, indicating an additional mode of virus-mediated host shut-off through transcriptional repression. Thus, increased transcription of a set of host genes contributes to a pro-lytic state that allows a subpopulation of cells to support the EBV lytic cycle.
2020-01-13 | GSE141220 | GEO
Project description:The Epstein-Barr virus (EBV) switches between latent and lytic phases in hosts that are important in developing related diseases. However, the underlying mechanism of how the viral latent-lytic switch is controlled and how EBV itself mediates this regulation remains largely unknown. This study identified the upregulated histone acetyl reader bromodomain-containing protein 7 (BRD7) during EBV latent infection. Based on the ChIP-sequencing of endogenous BRD7 in Burkitt lymphoma cells, we found that EBV drove BRD7 to regulate cellular and viral genomic loci, including the transcriptional activation of c-Myc, a recently reported regulator of EBV latency. Additionally, EBV-mediated BRD7 signals enriched around the FUSE site in chromosome 8, and the enhancer LOC108348026 in the lgH locus, which might activate the c-Myc alleles. Mechanically, EBV-encoded nuclear antigen 1 (EBNA1) bound and recruited BRD7 to colocalize at promotor regions of the related genes, thus serving as cofactors for the maintenance of viral latency. Moreover, the disruption of BRD7 decreased the c-Myc expression, induced the BZLF1 expression, and reactivated the lytic cycle. Our findings reveal the unique role of BRD7 hijacked by EBV in maintaining the viral latency state via chromatin remodeling. The study paved the way for understanding the new molecular mechanism of EBV-induced chromatin remodeling and latent-lytic switch regulation, providing novel therapeutic candidate targets for EBV persistent infection. With establishing persistent infection in most human hosts, EBV is usually at a latent infection state. How the viral latency is maintained in cells remains largely unknown. c-Myc was recently reported to act as a controller of the lytic switch, while whether and how EBV regulates it remains to be explored. Here, we identified that BRD7 is involved in controlling EBV latency. We found that EBV-mediated BRD7 was enriched in both the normal promoter regions and the translocation alleles of c-Myc, and the disruption of BRD7 decreased c-Myc expression to reactivate the lytic cycle. We also demonstrated that EBV-encoded EBNA1 bound to and regulated BRD7. Therefore, we reveal a novel mechanism by which EBV can regulate its infection state by hijacking host BRD7 to target c-Myc. Our findings will help future therapeutic intervention strategies of EBV infection and pathogenesis.
2022-05-14 | GSE202701 | GEO
Project description:A new actor of HCMV latency is unveiled, where KAP1 protein binds to viral genome to recruit SetDB1 and trigger H3K9 trimethylation. A switch of phosphorylation state mediated by mTOR leads to lytic replication, opening new approaches to curtail CMV infection but also to purge the virus from organ transplants.
2015-03-18 | GSE53271 | GEO
Project description:Epstein-Barr virus (EBV) Rta is a latent-lytic molecular switch evolutionarily conserved in all gamma-herpesviruses. In previous studies, doxycycline-inducible Rta was shown to potently produce an irreversible G1 arrest followed by cellular senescence in 293 cells. Here, we demonstrate that in this system the inducible Rta not only reactivates resident genome of EBV but also that of Kaposi’s sarcoma-associated herpesvirus (KSHV), to similar efficiency. However, Rta-induced senescence program was terminated by the robust viral lytic cycle replication that eventually caused cell death. Furthermore, prior to the abrupt expression of immediate-early protein (EBV BZLF1 or KSHV RTA), Rta simultaneously down-regulates cell cycle activators (c-Myc, CDK6, CCND2) and up-regulates senescence-related genes (p21, 14-3-3s). Since Rta is a viral immediate-early transcriptional activator, it is envisioned that during the initial stage of viral reactivation, Rta may engage to modulate the host transcriptome, to halt cell cycle progression, and to maintain an ideal environment for manufacturing infectious virions. Refer to individual Series. This SuperSeries is composed of the following subset Series: GSE24585: Expression profiling of host genes modulated by Epstein-Barr virus (EBV) Rta in HEK293 cells GSE24586: Expression profiling of host genes modulated by Epstein-Barr virus Rta in nasopharyngeal carcinoma cells
2011-03-31 | E-GEOD-24587 | biostudies-arrayexpress
Project description:Enhancers play indispensable roles in cell proliferation and survival through spatiotemporally regulating gene transcription. In addition, active enhancers and super-enhancers often produce noncoding enhancer RNAs (eRNAs) that precisely control RNA polymerase II activity. Kaposi’s sarcoma-associated herpesvirus (KSHV) is a human oncogenic gamma-2 herpesvirus that causes Kaposi’s sarcoma and lymphoproliferative diseases of B-cell origin such as primary effusion lymphoma (PEL). It is well characterized that KSHV utilizes host epigenetic and nuclear machineries to control the switch between two life cycles, latency and lytic replication. However, how KSHV impacts the host epigenome at different stages of viral life cycle is not well understood. Using the analysis of global run-on sequencing (GRO-seq) and chromatin-immunoprecipitation sequencing (ChIP-seq), we profiled the dynamics of host transcriptional regulatory elements during latency and lytic replication of KSHV-infected PEL cells. This study showed that a number of critical host genes for KSHV latency, including MYC proto-oncogene, were under the control of super-enhancers and eRNAs that were globally repressed upon viral reactivation. A combination of circular chromosome conformation capture combined with sequencing (4C-seq), GRO-seq and ChIP-seq indicated that the eRNA-expressing super-enhance regions were located at downstream of the MYC gene in KSHV-infected PELs. Treatment of an epigenetic drug to block enhancer function or shRNA-mediated depletion of the eRNA expression significantly reduced MYC mRNA expression in KSHV-infected PELs. Finally, while cellular IRF4 acted upon the eRNAs and super-enhancers for MYC expression during latency, the KSHV viral IRF4 repressed cellular IRF4 expression upon reactivation, decreasing MYC expression and thereby, facilitating lytic replication. Taken together, these data suggest that KSHV acts as an epigenetic driver that modifies host epigenomic status by effectively regulating enhancer function upon reactivation.
2020-03-17 | GSE147063 | GEO
Project description:Chromatin-organizing factors, like CTCF and cohesins, have been implicated in the control of complex viral regulatory programs. We investigated the role of CTCF and cohesin in the control of the latent to lytic switch for Kaposi's Sarcoma-Associated Herpesvirus (KSHV). We found that cohesin subunits, but not CTCF, were required for the repression of KSHV immediate early gene transcription. Depletion of cohesin subunits Rad21, SMC1, or SMC3 resulted in lytic cycle gene transcription and viral DNA replication. In contrast, depletion of CTCF failed to induce lytic transcription or DNA replication. ChiP-Seq analysis revealed that cohesins and CTCF bound to several sites within the immediate early control regions for ORF50 and more distal 5' sites that also regulate the divergently transcribed ORF45-46-47 gene cluster. Rad21 depletion led to a robust increase in ORF45 and ORF47 transcripts, with similar kinetics to that observed with chemical induction by sodium butyrate. During latency, the chromatin between the ORF45 and ORF50 transcription start sites was enriched in histone H3K4me3 with elevated H3K9ac at the ORF45 promoter and elevated H3K27me3 at the ORF50 promoter. A paused form of RNA pol II was loosely associated with the ORF45 promoter region during latency, but was converted to an active elongating form upon reactivation induced by Rad21 depletion. Butyrate-induced transcription of ORF45 and ORF47 was resistant to cyclohexamide, suggesting that these genes have immediate early features similar to ORF50. Butyrate-treatment caused the rapid dissociation of cohesins and loss of CTCF binding at the immediate early gene locus, suggesting that cohesins may be a direct target of butyrate-mediated lytic induction. Our findings implicate cohesins as a major repressor of KSHV lytic gene activation, and function coordinately with CTCF to regulate the switch between latent and lytic gene activity. Study of chromatin-organizing factors, like CTCF and cohesins.
2012-06-02 | E-GEOD-38411 | biostudies-arrayexpress
Project description:Abstract: The transcriptional program associated with herpesvirus latency and the viral genes regulating entry into and exit from latency are poorly understood and controversial. Here, we developed and validated a targeted enrichment platform and conducted large-scale transcriptome analyses of human cytomegalovirus (HCMV) infection. We used both an experimental hematopoietic cell model of latency, and cells from naturally infected, healthy human subjects (clinical) to define the breadth of viral genes expressed. The viral transcriptome derived from experimental infection was highly correlated with that from clinical infection, validating our experimental latency model. These transcriptomes revealed a broader profile of gene expression during infection in hematopoietic cells than previously appreciated. Further, using recombinant viruses that establish a non-reactivating, latent-like or replicative infection in CD34+ hematopoietic progenitors (HPCs), we defined classes of low to moderately expressed genes that are differentially regulated in latent vs. replicative states of infection. Most of these genes have yet to be studied in depth. By contrast, genes that were highly expressed, were expressed similarly in both latent and replicative infection. From these findings, a model emerges whereby low or moderately expressed genes may have the greatest impact on regulating the switch between viral latency and replication. The core set of viral genes expressed in natural infection and differentially regulated depending on the pattern of infection provides novel insight into the HCMV transcriptome associated with latency in the host and a resource for investigating new virus-host interactions underlying persistence. Significance: Herpesviruses have an extraordinarily complex relationship with their host, persisting for the lifetime of the host by way of a latent infection. Reactivation of replication is associated with significant disease risk, particularly in immunocompromised individuals. We characterize in depth transcriptional profiles of HCMV latency. We show that a broad and concordant viral transcriptome is found in both an experimental model of latency and in asymptomatically infected individuals. We further define genes that are differentially regulated during latent and replicative states- candidates for key regulators controlling the switch between latency and reactivation. This work will help understand the persistence of complex DNA viruses and provides a path towards developing antiviral strategies to control herpesvirus entry into and exit from latency.
2017-12-04 | GSE99823 | GEO