scholarly journals Inhibitory Effect of Epstein-Barr Virus Gene-Ebna1 on Human Tnfrp55 Gene Expression

2012 ◽  
Vol 56 (3) ◽  
pp. 271-274
Author(s):  
Joanna Krzowska-Firych ◽  
Hanna Fota-Markowska ◽  
Barbara Marzec-Kotarska ◽  
Roma Modrzewska ◽  
Jacek Wojcierowski
Keyword(s):  
Gene Expression ◽  
Epstein Barr Virus ◽  
Human Peripheral Blood ◽  
Rnase Protection Assay ◽  
Inhibitory Effect ◽  
Gene Encoding ◽  
Rnase Protection ◽  
Barr Virus ◽  
Epstein Barr ◽  
Ebna1 Gene

Abstract The aim of the study was to assess the expression of TNFRp55 mRNA and to examine if the antisense inhibition of Epstein-Barr virus (EBV) encoded EBNA1 gene product alters the expression of gene encoding TNFRp55 in lymphoblastoid cell line (LCL). The experiment was performed on LCL derived from EBV infected human peripheral blood B lymphocytes. The lymphocytes were isolated and cultured. RNA was isolated and examined according to the RNase protection assay. The hybridisation was done with HCR-4 probe. RNA was quantified by densitometry and presented in extinction units. The level of expression was calculated with TotaILab software programme. The results of the study suggest that EBV gene, responsible for the synthesis of EBNA1 protein, has an inhibitory effect on human TNFRp55 gene expression in LCL.

scholarly journals Direct and Indirect Regulation of Cytokine and Cell Cycle Proteins by EBNA-2 during Epstein-Barr Virus Infection

2001 ◽  
Vol 75 (8) ◽  
pp. 3537-3546 ◽  
Author(s):  
Lindsay C. Spender ◽  
Georgina H. Cornish ◽  
Benjamin Rowland ◽  
Bettina Kempkes ◽  
Paul J. Farrell
Keyword(s):  
Cell Cycle ◽  
Epstein Barr Virus ◽  
Transient Transfection ◽  
Cyclin D2 ◽  
Transient Transfection Assay ◽  
Rnase Protection ◽  
Barr Virus ◽  
Tnf Α ◽  
Epstein Barr ◽  
Transfection Assay

ABSTRACT We have studied the pathways of regulation of cytokine and cell cycle control proteins during infection of human B lymphocytes by Epstein-Barr virus (EBV). Among 30 cytokine RNAs analyzed by the RNase protection assay, tumor necrosis factor alpha (TNF-α), granulocyte colony-stimulating factor, lymphotoxin (LT), and LTβ were found to be regulated within 20 h of EBV infection of primary B cells. Similar results were obtained using the estrogen-regulated EBNA-2 cell line EREB2.5, in which RNAs for LT and TNF-α were induced within 6 h of activation of EBNA-2. Expression of Notch also caused an induction of TNF-α RNA. The induction of TNF-α RNA by EBNA-2 was indirect, and constitutive expression of either LMP-1 or c-myc proteins did not substitute for EBNA-2 in induction of TNF-α RNA. Cyclin D2 is also an indirect target of EBNA-2-mediated transactivation. EBNA-2 was found to activate the cyclin D2 promoter in a transient-transfection assay. A mutant of EBNA-2 that does not bind RBP-Jκ retained some activity in this assay, and activation did not depend on the presence of B-cell-specific factors. Deletion analysis of the cyclin D2 promoter revealed that removal of sequences containing E-box c-myc consensus DNA binding sequences did not reduce EBNA-2-mediated activation of the cyclin D2 promoter in the transient-transfection assay. The results indicate that cytokines are an early target of EBNA-2 and that EBNA-2 can regulate cyclin D2 transcription in EBV-infected cells by mechanisms additional to the c-myc pathway.

scholarly journals Epstein-Barr Virus miR-BART6-3p Inhibits the RIG-I Pathway

2017 ◽  
Vol 9 (6) ◽  
pp. 574-586 ◽  
Author(s):  
Yuanjun Lu ◽  
Zailong Qin ◽  
Jia Wang ◽  
Xiang Zheng ◽  
Jianhong Lu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Epstein Barr Virus ◽  
Type I ◽  
Receptor Signaling ◽  
Viral Pathogen ◽  
Infection Period ◽  
Barr Virus ◽  
Ebv Infection ◽  
Epstein Barr

Recognition of viral pathogen-associated molecular patterns by pattern recognition receptors (PRRs) is the first step in the initiation of a host innate immune response. As a PRR, RIG-I detects either viral RNA or replication transcripts. Avoiding RIG-I recognition is a strategy employed by viruses for immune evasion. Epstein-Barr virus (EBV) infects the majority of the human population worldwide. During the latent infection period there are only a few EBV proteins expressed, whereas EBV-encoded microRNAs, such as BART microRNAs, are highly expressed. BART microRNAs regulate both EBV and the host's gene expression, modulating virus proliferation and the immune response. Here, through gene expression profiling, we found that EBV miR-BART6-3ps inhibited genes of RIG-I-like receptor signaling and the type I interferon (IFN) response. We demonstrated that miR-BART6-3p rather than other BARTs specifically suppressed RIG-I-like receptor signaling-mediated IFN-β production. RNA-seq was used to analyze the global transcriptome change upon EBV infection and miR-BART6-3p mimics transfection, which revealed that EBV infection-triggered immune response signaling can be repressed by miR-BART6-3p overexpression. Furthermore, miR-BART6-3p inhibited the EBV-triggered IFN-β response and facilitated EBV infection through targeting the 3′UTR of RIG-I mRNA. These findings provide new insights into the mechanism underlying the strategies employed by EBV to evade immune surveillance.

scholarly journals Identification of potential hot spots in the carboxy-terminal part of the Epstein-Barr virus (EBV) BNLF-1 gene in both malignant and benign EBV-associated diseases: high frequency of a 30-bp deletion in Malaysian and Danish peripheral T-cell lymphomas

Blood ◽  
1994 ◽  
Vol 84 (12) ◽  
pp. 4053-4060 ◽  
Author(s):  
K Sandvej ◽  
SC Peh ◽  
BS Andresen ◽  
G Pallesen
Keyword(s):  
T Cell ◽  
Hot Spots ◽  
Epstein Barr Virus ◽  
Terminal Part ◽  
Gene Encoding ◽  
Single Base ◽  
Barr Virus ◽  
T Cell Lymphomas ◽  
Epstein Barr ◽  
Peripheral T Cell Lymphomas

In this study, we have sequenced the C-terminal part of the Epstein- Barr virus (EBV)-BNLF-1 gene encoding for the latent membrane protein-1 from tissues of EBV-positive Danish Hodgkin's disease (HD) and of Danish and Malaysian peripheral T-cell lymphomas (PTLs) and from tonsils of Danish infectious mononucleosis (IM). Our study showed that some of the 7 single-base mutations and the 30-bp deletion previously detected between codons of amino acid 322 and 366 in the BNLF-1 gene of the nasopharyngeal carcinoma cell line CAO were present in all Malaysian PTLs and in 60% of the Danish PTLs. In HD and the IM cases, the mutations were present in about 30%. The 30-bp deletion and the single base mutations occurred independently, and mutations were detectable in the majority of EBV type B-positive cases. These findings suggest that the 30-bp deletion and the 7 single-base mutations in the C-terminal part of the CAO-BNLF-1 gene do not characterize a new EBV type A substrain. Rather, some of the positions of single base mutations and the 30-bp deletion are hot spots that may have mutated independently through the evolution of EBV strains.

Epstein-Barr Virus Gene Expression in Lymphomas Induced by the Virus in the Cottontop Tamarin

1989 ◽  
pp. 141-144
Author(s):  
S. Finerty ◽  
L. S. Young ◽  
L. Brooks ◽  
F. T. Scullion ◽  
A. B. Rickinson ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epstein Barr Virus ◽  
Virus Gene ◽  
Barr Virus ◽  
Virus Gene Expression ◽  
Epstein Barr

scholarly journals Epstein-Barr Virus Facilitates Expression of KLF14 by Regulating the Cooperative Binding of the E2F-Rb-HDAC Complex in Latent Infection

2020 ◽  
Vol 94 (22) ◽  
Author(s):  
Yonggang Pei ◽  
Josiah Hiu-yuen Wong ◽  
Hem Chandra Jha ◽  
Tian Tian ◽  
Zhi Wei ◽  
...  
Keyword(s):  
Gene Expression ◽  
Human Population ◽  
Regulatory Networks ◽  
Epstein Barr Virus ◽  
Latent Infection ◽  
Human Tumor ◽  
Barr Virus ◽  
Repressor Complex ◽  
Tumor Virus ◽  
Epstein Barr

ABSTRACT Epstein-Barr virus (EBV) was discovered as the first human tumor virus more than 50 years ago. EBV infects more than 90% of the human population worldwide and is associated with numerous hematologic malignancies and epithelial malignancies. EBV establishes latent infection in B cells, which is the typical program seen in lymphomagenesis. Understanding EBV-mediated transcription regulatory networks is one of the current challenges that will uncover new insights into the mechanism of viral-mediated lymphomagenesis. Here, we describe the regulatory profiles of several cellular factors (E2F6, E2F1, Rb, HDAC1, and HDAC2) together with EBV latent nuclear antigens using next-generation sequencing (NGS) analysis. Our results show that the E2F-Rb-HDAC complex exhibits similar distributions in genomic regions of EBV-positive cells and is associated with oncogenic super-enhancers involving long-range regulatory regions. Furthermore, EBV latent antigens cooperatively hijack this complex to bind at KLFs gene loci and facilitate KLF14 gene expression in lymphoblastoid cell lines (LCLs). These results demonstrate that EBV latent antigens can function as master regulators of this multisubunit repressor complex (E2F-Rb-HDAC) to reverse its suppressive activities and facilitate downstream gene expression that can contribute to viral-induced lymphomagenesis. These results provide novel insights into targets for the development of new therapeutic interventions for treating EBV-associated lymphomas. IMPORTANCE Epstein-Barr virus (EBV), as the first human tumor virus, infects more than 90% of the human population worldwide and is associated with numerous human cancers. Exploring EBV-mediated transcription regulatory networks is critical to understand viral-associated lymphomagenesis. However, the detailed mechanism is not fully explored. Now we describe the regulatory profiles of the E2F-Rb-HDAC complex together with EBV latent antigens, and we found that EBV latent antigens cooperatively facilitate KLF14 expression by antagonizing this multisubunit repressor complex in EBV-positive cells. This provides potential therapeutic targets for the treatment of EBV-associated cancers.

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