Nascent transcriptomics reveal cellular pro-lytic factors upregulated upstream of the latency-to-lytic switch protein of Epstein-Barr virus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA592709 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR10564907.fastq.gz | Fastqsanger.gz | |||
| SRR10564908.fastq.gz | Fastqsanger.gz | |||
| SRR10564909.fastq.gz | Fastqsanger.gz | |||
| SRR10564910.fastq.gz | Fastqsanger.gz | |||
| SRR10564911.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 18 |
Similar Datasets
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:Epstein-Barr virus (EBV) has a lifelong latency period after initial infection. Rarely, however, when the EBV immediate early gene BZLF1 is expressed by a specific stimulus, the virus switches to the lytic cycle to produce progeny viruses. We found that EBV infection reduced levels of various ceramide species in gastric cancer cells. As ceramide is a bioactive lipid implicated in the infection of various viruses, we assessed the effect of ceramide on the EBV lytic cycle. Treatment with C6-ceramide (C6-Cer) induced an increase in the endogenous ceramide pool and increased production of the viral product as well as BZLF1 expression. Treatment with the ceramidase inhibitor ceranib-2 induced EBV lytic replication with an increase in the endogenous ceramide pool. The glucosylceramide synthase inhibitor Genz-123346 inhibited C6-Cer-induced lytic replication. C6-Cer induced ERK1/2 and CREB phosphorylation, c-JUN expression, and accumulation of the autophagosome marker LC3B. Treatment with MEK1/2 inhibitor U0126 or autophagy initiation inhibitor 3-MA suppressed C6-Cer-induced EBV lytic replication. In contrast, the autophagosome-lysosome fusion inhibitor chloroquine induced BZLF1 expression. Transfection with siCREB reduced ERK1/2 phosphorylation and C6-Cer-induced BZLF1 expression. On the other hand, siJUN transfection did not affect BZLF1 expression. Our results show that increased endogenous ceramide and glycosyl ceramide (GlyCer) following C6-Cer treatment induce EBV lytic replication in gastric cancer cells via ERK1/2 and CREB phosphorylation and autophagosome accumulation.
2023-12-20 | MTBLS7649 | MetaboLights
Project description:Previously, we identified Syncytin1 to be expressed in human B cells and enhance EBV ability to undergo lytic replication. To gain mechanistic insight, we performed liquid chromatography tandem mass spectrometry (LC-MS/MS) on tryptic peptides from immunoprecipitated FLAG-tagged Syncytin-1 in latently infected EBV+ Burkitt lymphoma cells. This revealed a number of cellular proteins as potential Syncytin-1 interacting partners during latency and/or during the lytic phase as well as two EBV lytic phase proteins, the viral protein kinase and LF2, a negative regulator of EBV lytic gene transcription. We now find that Syncytin1 reduces the association between LF2 and the EBV replication and transcription activator to promote EBV lytic gene expression.
2023-05-15 | MSV000091949 | MassIVE
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:Our appreciation for the extent of Epstein Barr virus (EBV) transcriptome complexity continues to grow through findings of EBV encoded microRNAs, new long non-coding RNAs, and hundreds of new polyadenylated lytic transcripts. Here we report an additional layer to the EBV transcriptome through the identification of a repertoire of latent and lytic viral circRNAs. Utilizing RNase R-sequencing with cell models representing latency types I, II, and III, we identified circRNAs expressed from the latency Cp promoter involving backsplicing from the W1 and W2 exons to the C1 exon, from the EBNA BamHI U exon, and from the latency long-non-coding RPMS1 locus. We also identified circRNAs expressed during reactivation including an exon 8-to-2 backspliced LMP2 transcript and a highly expressed circRNA derived from the BHLF1 gene. Altogether we identified over 30 EBV circRNA candidates and validated and determined the structural features, expression profiles and nuclear-cytoplasmic distributions of several prominent viral circRNAs. Further, we show that two RPMS1 circRNAs are expressed in stomach cancer specimens. This study increases the known EBV latency and lytic transcriptome repertoires to include viral circRNAs and provides an essential foundation for investigations into the functions of this new class of EBV transcripts in EBV biology and disease.
2018-07-12 | GSE116675 | GEO
Project description:The Epstein-Barr virus (EBV) employs lytic replication to facilitate viral propagation and pathogenesis; however, the regulatory mechanisms governing this process remain incompletely elucidated. Here, we identify LMP2A-IT1, a novel 276-nt RNA derived from the first intron of the LMP2A gene. This transcript directly interacts with the nuclear export factor exportin 5 (XPO5) and exhibits predominant cytoplasmic localization. Functionally, LMP2A-IT1 expression is markedly upregulated during EBV lytic reactivation and subsequently amplifies viral gene expression and DNA replication—a phenomenon further supported by the positive correlation between LMP2A-IT1 levels and EBV DNA copy numbers in human nasopharyngeal carcinoma tissues. Mechanistically, cytoplasmic LMP2A-IT1 likely activates inflammatory response, thereby upregulating the immediate-early transactivators BZLF1 and BRLF1 to initiate the EBV lytic cycle. Our study establishes LMP2A-IT1 as a novel EBV-encoded RNA and reveals its function as a key positive feedback regulator of EBV lytic replication. These findings provide new insights into EBV replication dynamics and underscore the functional significance of viral RNAs in EBV biology.
2026-02-24 | GSE320354 | GEO
Project description:The Epstein Barr virus (EBV) is a human gammaherpesvirus which infects over 90% of the global population and is associated with lymphoid and epithelioid cancers. After infection, EBV enters a latent state in B-cells where the viral genome persists as a nuclear episome maintained by expression of a small number of latency-associated viral proteins. The lytic viral proteins, required for DNA replication and virion production, are silenced by cellular epigenetic mechanisms. The immediate-early lytic gene BZLF1 is the most important target for transcriptional repression, as its expression triggers the entire lytic cascade. To gain insight into the factors restricting BZLF1 expression, we used the PICh method of locus specific proteomics (Proteomics of Isolated Chromatin segments) to identify proteins which occupy BZLF1 promoter DNA. We show that the nucleosome remodeler CHD4 and components of the Polycomb complex PRC1 are novel repressors of BZLF1 and that both are required to prevent spontaneous lytic reactivation in Burkitt lymphoma cells. We also reveal a marked, cell wide loss of the PRC1 histone mark (H2AK119Ub) during the lytic cycle which is dependent on immediate-early and early lytic gene expression. A proteomic analysis of Burkitt lymphoma cells containing lytic EBV identified upregulation of human de-ubiquitinase USP17 as a candidate for H2AK119Ub removal. Our study demonstrates the power of proteomic approaches to identify repressors of EBV reactivation and provides new insight into how EBV manipulates epigenetic mechanisms during the lytic cycle.
2026-02-11 | PXD068122 | Pride
Project description:We have previously shown that the Epstein-Barr virus (EBV) likely encodes hundreds of viral long non-coding RNAs (vlncRNAs) that are expressed during reactivation. Here we show that the EBV latency origin of replication (oriP) is transcribed bi-directionally during reactivation and that both leftward (oriPtLs) and rightward transcripts (oriPtRs) are largely localized in the nucleus. While the oriPtLs are most likely non-coding, at least some of the oriPtRs contain the BCRF1/vIL10 open reading frame. Nonetheless, oriPtR transcripts with long 5’UTRs may partially serve non-coding functions. Both oriPtL and oriPtR transcripts are expressed with late kinetics and their expression is inhibited by phosphonoacetic acid. RNA-seq analysis showed that oriPtLs and oriPtRs exhibited extensive “hyper-editing” at their Family of Repeat (FR) regions. RNA secondary structure prediction revealed that the FR region of both oriPtLs and oriPtRs may form large evolutionarily conserved and thermodynamically stable hairpins. The double-stranded RNA-binding protein and RNA-editing enzyme ADAR was found to bind to oriPtLs, likely facilitating editing of the FR hairpin. Further, the multifunctional paraspeckle protein, NONO, was found to bind to oriPt transcripts suggesting that oriPts interacts with the paraspeckle-based innate anti-viral immune pathway. Knock-down and ectopic expression of oriPtLs showed that it contributes to global viral lytic gene expression and viral DNA replication. Together, these results show that these new vlncRNAs interact with cellular innate immune pathways and that they help facilitate progression of the viral lytic cascade. RNA-seq analysis for oriPtL knockdown and overexpression experiments
2015-05-21 | E-GEOD-68122 | biostudies-arrayexpress
Project description: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 post-translationally 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 could ultimately contribute to an EBV-specific treatment strategy for AIDS-related or post-transplant lymphomas.
2018-06-27 | GSE115829 | 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 activated only when expression of the EBV latent-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 on the expression of ZEBRA, 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 various degrees in latently infected cells that respond to mechanistically distinct lytic triggers. While increased expression of these cellular genes defines a prolytic state, such upregulation also runs counter to the well-known mechanism of viral-nuclease-mediated host shutoff that is activated downstream of ZEBRA. Furthermore, a subset of upregulated cellular genes is transcriptionally repressed temporally downstream of ZEBRA, indicating an additional mode of virus-mediated host shutoff through transcriptional repression. Thus, increased transcription of a set of host genes contributes to a prolytic state that allows a subpopulation of cells to support the EBV lytic cycle.IMPORTANCE Transition from latency to the lytic phase is necessary for herpesvirus-mediated pathology as well as viral spread and persistence in the population at large. Yet, viral genomes in only some cells in a population of latently infected cells respond to lytic triggers, resulting in subpopulations of responsive/lytic and refractory cells. Our investigations into this partially permissive phenotype of the herpesvirus Epstein-Barr virus (EBV) indicate that upon exposure to lytic triggers, certain cellular genes are transcriptionally upregulated, while viral latency genes are downregulated ahead of expression of the viral latent-to-lytic switch protein. These cellular genes contribute to lytic susceptibility to various degrees. Apart from indicating that there may be a cellular "prolytic" state, our findings indicate that (i) early transcriptional upregulation of cellular genes counters the well-known viral-nuclease-mediated host shutoff and (ii) subsequent transcriptional downregulation of a subset of early upregulated cellular genes is a previously undescribed mode of host shutoff.
| S-EPMC7081890 | biostudies-literature