| Structural highlights
Function
BZLF1_EBVB9 Plays a key role in the switch from latent infection to lytic cycle producing new virions. Acts as a transcription factor, inducing early lytic cycle genes, and as a origin binding protein for genome replication. BZLF1 activates the promoter of another EBV gene (BSLF2+BMLF1).[1] [2] [3] [4] [5]
Publication Abstract from PubMed
In infected cells, Epstein-Barr virus (EBV) alternates between latency and lytic replication. The viral bZIP transcription factor ZEBRA (Zta, BZLF1) regulates this cycle by binding to two classes of ZEBRA response elements (ZREs): CpG-free motifs resembling the consensus AP-1 site recognized by cellular bZIP proteins and CpG-containing motifs that are selectively bound by ZEBRA upon cytosine methylation. We report structural and mutational analysis of ZEBRA bound to a CpG-methylated ZRE (meZRE) from a viral lytic promoter. ZEBRA recognizes the CpG methylation marks through a ZEBRA-specific serine and a methylcytosine-arginine-guanine triad resembling that found in canonical methyl-CpG binding proteins. ZEBRA preferentially binds the meZRE over the AP-1 site but mutating the ZEBRA-specific serine to alanine inverts this selectivity and abrogates viral replication. Our findings elucidate a DNA methylation-dependent switch in ZEBRA's transactivation function that enables ZEBRA to bind AP-1 sites and promote viral latency early during infection and subsequently, under appropriate conditions, to trigger EBV lytic replication by binding meZREs.
Structural basis of DNA methylation-dependent site selectivity of the Epstein-Barr virus lytic switch protein ZEBRA/Zta/BZLF1.,Bernaudat F, Gustems M, Gunther J, Oliva MF, Buschle A, Gobel C, Pagniez P, Lupo J, Signor L, Muller CW, Morand P, Sattler M, Hammerschmidt W, Petosa C Nucleic Acids Res. 2022 Jan 11;50(1):490-511. doi: 10.1093/nar/gkab1183. PMID:34893887[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Packham G, Economou A, Rooney CM, Rowe DT, Farrell PJ. Structure and function of the Epstein-Barr virus BZLF1 protein. J Virol. 1990 May;64(5):2110-6. PMID:2157874
- ↑ Kouzarides T, Packham G, Cook A, Farrell PJ. The BZLF1 protein of EBV has a coiled coil dimerisation domain without a heptad leucine repeat but with homology to the C/EBP leucine zipper. Oncogene. 1991 Feb;6(2):195-204. PMID:1847997
- ↑ Schepers A, Pich D, Hammerschmidt W. A transcription factor with homology to the AP-1 family links RNA transcription and DNA replication in the lytic cycle of Epstein-Barr virus. EMBO J. 1993 Oct;12(10):3921-9. PMID:8404860
- ↑ Wen W, Iwakiri D, Yamamoto K, Maruo S, Kanda T, Takada K. Epstein-Barr virus BZLF1 gene, a switch from latency to lytic infection, is expressed as an immediate-early gene after primary infection of B lymphocytes. J Virol. 2007 Jan;81(2):1037-42. Epub 2006 Nov 1. PMID:17079287 doi:10.1128/JVI.01416-06
- ↑ McDonald CM, Petosa C, Farrell PJ. Interaction of Epstein-Barr virus BZLF1 C-terminal tail structure and core zipper is required for DNA replication but not for promoter transactivation. J Virol. 2009 Apr;83(7):3397-401. doi: 10.1128/JVI.02500-08. Epub 2009 Jan 14. PMID:19144704 doi:10.1128/JVI.02500-08
- ↑ Bernaudat F, Gustems M, Günther J, Oliva MF, Buschle A, Göbel C, Pagniez P, Lupo J, Signor L, Müller CW, Morand P, Sattler M, Hammerschmidt W, Petosa C. Structural basis of DNA methylation-dependent site selectivity of the Epstein-Barr virus lytic switch protein ZEBRA/Zta/BZLF1. Nucleic Acids Res. 2022 Jan 11;50(1):490-511. PMID:34893887 doi:10.1093/nar/gkab1183
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