Nuclear DNA-binding Proteins Determined by the Epstein-Barr Virus-related Simian Lymphotropic Herpesviruses H. gorilla, H. pan, H. pongo and H. papio

The human gamma-herpesviruses Epstein–Barr virus (EBV) (HHV-4) and Kaposi’s sarcoma-associated herpesvirus (KSHV) (HHV-8) are responsible for a number of diseases, including various types of cancer. Epstein–Barr nuclear antigen 1 (EBNA1) from EBV and latency-associated nuclear antigen (LANA) from KSHV are viral-encoded DNA-binding proteins that are essential for the replication and maintenance of their respective viral genomes during latent, oncogenic infection. As such, EBNA1 and LANA are attractive targets for the development of small-molecule inhibitors. To this end, we performed a biophysical screen of EBNA1 and LANA using a fragment library by saturation transfer difference (STD)–NMR spectroscopy and surface plasmon resonance (SPR). We identified and validated a number of unique fragment hits that bind to EBNA1 or LANA. We also determined the high-resolution crystal structure of one fragment bound to EBNA1. Results from this screening cascade provide new chemical starting points for the further development of potent inhibitors for this class of viral proteins.

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A Major DNA Binding Protein Encoded by BALF2 Open Reading Frame of Epstein–Barr Virus (EBV) Forms a Complex with Other EBV DNA-Binding Proteins: DNAase, EA-D, and DNA Polymerase

Virology ◽

10.1006/viro.1997.8891 ◽

1997 ◽

Vol 239 (2) ◽

pp. 285-295 ◽

Cited By ~ 29

Author(s):

Yué Zeng ◽

Jaap Middeldorp ◽

Jean-Jacques Madjar ◽

Tadamasa Ooka

Keyword(s):

Dna Binding ◽

Dna Polymerase ◽

Epstein Barr Virus ◽

Dna Binding Protein ◽

Dna Binding Proteins ◽

Open Reading Frame ◽

Reading Frame ◽

Barr Virus ◽

Ebv Dna ◽

Epstein Barr

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Solubilization of the Epstein-Barr virus-determined nuclear antigen and its characterization as a DNA-binding protein.

Journal of Virology ◽

10.1128/jvi.22.1.1-8.1977 ◽

1977 ◽

Vol 22 (1) ◽

pp. 1-8 ◽

Cited By ~ 47

Author(s):

J Luka ◽

W Siegert ◽

G Klein

Keyword(s):

Dna Binding ◽

Epstein Barr Virus ◽

Binding Protein ◽

Dna Binding Protein ◽

Nuclear Antigen ◽

Barr Virus ◽

Epstein Barr

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DNA-binding-defective mutants of the Epstein-Barr virus lytic switch activator Zta transactivate with altered specificities

Molecular and Cellular Biology ◽

10.1128/mcb.14.5.3041-3052.1994 ◽

1994 ◽

Vol 14 (5) ◽

pp. 3041-3052

Author(s):

E K Flemington ◽

J P Lytle ◽

C Cayrol ◽

A M Borras ◽

S H Speck

Keyword(s):

Dna Binding ◽

Epstein Barr Virus ◽

Lytic Cycle ◽

Promoter Elements ◽

Barr Virus ◽

Binding Forms ◽

Viral Genes ◽

Direct Binding ◽

Epstein Barr ◽

Necessary And Sufficient

The Epstein-Barr virus BRLF1 and BZLF1 genes are the first viral genes transcribed upon induction of the viral lytic cycle. The protein products of both genes (referred to here as Rta and Zta, respectively) activate expression of other viral genes, thereby initiating the lytic cascade. Among the viral antigens expressed upon induction of the lytic cycle, however, Zta is unique in its ability to disrupt viral latency; expression of the BZLF1 gene is both necessary and sufficient for triggering the viral lytic cascade. We have previously shown that Zta can activate its own promoter (Zp), through binding to two Zta recognition sequences (ZIIIA and ZIIIB). Here we describe mutant Zta proteins that do not bind DNA (referred to as Zta DNA-binding mutants [Zdbm]) but retain the ability to transactivate Zp. Consistent with the inability of these mutants to bind DNA, transactivation of Zp by Zdbm is not dependent on the Zta recognition sequences. Instead, transactivation by Zdbm is dependent upon promoter elements that bind cellular factors. An examination of other viral and cellular promoters identified promoters that are weakly responsive or unresponsive to Zdbm. An analysis of a panel of artificial promoters containing one copy of various promoter elements demonstrated a specificity for Zdbm activation that is distinct from that of Zta. These results suggest that non-DNA-binding forms of some transactivators retain the ability to transactivate specific target promoters without direct binding to DNA.

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Synergistic action of interleukin-6 and glucocorticoids is mediated by the interleukin-6 response element of the rat alpha 2 macroglobulin gene

Molecular and Cellular Biology ◽

10.1128/mcb.12.5.2282-2294.1992 ◽

1992 ◽

Vol 12 (5) ◽

pp. 2282-2294

Author(s):

G M Hocke ◽

D Barry ◽

G H Fey

Keyword(s):

Dna Binding ◽

Acute Phase ◽

Interleukin 6 ◽

Binding Proteins ◽

Nuclear Dna ◽

Acute Phase Proteins ◽

Dna Binding Proteins ◽

Human Hepatoma Cells ◽

Response Element ◽

Multiple Copies

One class of genes coding for the acute-phase proteins (acute-phase genes) is induced by interleukin 6 (IL-6) through the human transcription factor NF-IL-6 and its rat homolog IL-6-DBP/LAP. A second class, represented by the rat alpha 2 macroglobulin gene, utilizes a different IL-6 response element (IL-6-RE) and different DNA-binding proteins interacting with this element, the so-called IL-6-RE binding proteins (IL-6 RE-BPs). Human Hep3B and HepG2 hepatoma, U266 myeloma, and CESS lymphoblastoid cells contain IL-6 RE-BPs that form complexes, with the IL-6-RE, with gel mobilities indistinguishable from those of the corresponding complexes of rat liver cells. The ability to form these complexes was induced by IL-6 in human hepatoma cells with a maximum reached after 4 h and required ongoing protein synthesis. Multiple copies of an 18-bp element containing the IL-6-RE core were sufficient to confer both induction by IL-6 and a synergistic induction by IL-6 plus glucocorticoids to minimal promoters. The synergism was blocked by the receptor antagonist RU486 and thus was dependent on the glucocorticoid receptor (GR). However, the 18-bp element contained no consensus GR-binding site, and recombinant GR did not bind at this sequence. Therefore, the synergism was probably achieved by an indirect effect of a glucocorticoid-activated intermediate gene on the IL-6 RE-BPs. The rat IL-6 RE-BP had a molecular weight of 102 +/- 10 kDa and was thus distinct from NF-IL-6 and IL-6-DBP/LAP. Therefore, IL-6 must activate two different classes of liver acute-phase genes through at least two different nuclear DNA-binding proteins: NF-IL-6/IL-6-DBP/LAP and the IL-6 RE-BP.

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Epstein–Barr virus induces a distinct form of DNA-bound STAT1 compared with that found in interferon-stimulated B lymphocytes

Journal of General Virology ◽

10.1099/vir.0.82741-0 ◽

2007 ◽

Vol 88 (7) ◽

pp. 1876-1886 ◽

Cited By ~ 13

Author(s):

James McLaren ◽

Martin Rowe ◽

Paul Brennan

Keyword(s):

Dna Binding ◽

Epstein Barr Virus ◽

Lymphoblastoid Cell Lines ◽

Distinct Form ◽

Post Translational Modifications ◽

Constitutive Activation ◽

Barr Virus ◽

Molecular Identity ◽

Infected Cells ◽

Epstein Barr

Since ‘constitutive activation’ of STAT1 was first described in Epstein–Barr virus (EBV)-immortalized lymphoblastoid cell lines (LCLs), there has been controversy regarding the molecular identity of the STAT1 DNA-binding complex found in these cells. The post-translational modifications of STAT1 in LCLs have been analysed and an LMP1-induced STAT1 DNA-binding complex, different from that generated by alpha interferon (IFN) stimulation and not involving tyrosine phosphorylation, is demonstrated. STAT1 is serine-phosphorylated downstream of PI3K and MEK in LCLs and this modification restricts IFN-stimulated STAT1–DNA binding. These data suggest that EBV induces a distinct form of DNA-bound STAT1 in virus-infected cells.

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