Cyclic AMP-responsive element-dependent activation of Epstein-Barr virus zebra promoter by human herpesvirus 6.
We have recently shown that infection of Epstein-Barr virus (EBV) genome-positive B cells by human herpesvirus 6 (HHV-6) results in the expression of the immediate-early EBV Zebra gene, followed by virus replication (L. Flamand, I. Stefanescu, D. V. Ablashi, and J. Menezes, J. Virol. 67:6768-6777, 1993). Here we show that HHV-6 upregulates Zebra gene transcription through a cyclic AMP-responsive element (CRE) located within the Zebra promoter (Zp). Using human B- or T-cell lines transfected with ZpCat reporter gene constructs, we demonstrate that a region designated the ZII domain of Zp is the target of HHV-6 transactivation. Mutation of the consensus AP-1/CRE site within ZII abolished the inducibility of Zp by HHV-6, whereas positioning of the ZII domain upstream of the beta-globin minimal promoter conferred responsiveness following HHV-6 infection. Binding of these factors to ZII was prevented by oligonucleotides containing CRE but not by AP-1 consensus sequences. Antibodies against CRE-binding (CREB) protein but not against c-Fos or c-Jun were able to supershift the DNA-protein complex, identifying the nature of the transcription factor which binds to ZII as a member of the CREB family of proteins. Finally, transfection of CREB protein and protein kinase A expression vectors were found to activate Zp in Jurkat cells, suggesting that phosphorylated form of CREB protein can play a determining role in the EBV reactivation process.
Flamand
L
L
Laboratory of Immunovirology, University of Montreal, Quebec, Canada.
Menezes
J
J
D001402:B-Lymphocytes / Q000166:cytology / Q000821:virology; D001483:Base Sequence; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D004279:DNA, Viral; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015967:Gene Expression Regulation, Viral; D015654:Herpesvirus 6, Human / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D019384:Nucleic Acid Synthesis Inhibitors; D010746:Phosphonoacetic Acid / Q000494:pharmacology; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger; D012367:RNA, Viral; D013601:T-Lymphocytes / Q000166:cytology / Q000821:virology; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism; D015533:Transcriptional Activation; D014764:Viral Proteins
C063676:BZLF1 protein, Herpesvirus 4, Human; D017362:Cyclic AMP Response Element-Binding Protein; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D019384:Nucleic Acid Synthesis Inhibitors; D012333:RNA, Messenger; D012367:RNA, Viral; D015534:Trans-Activators; D018808:Transcription Factor AP-1; D014764:Viral Proteins; D010746:Phosphonoacetic Acid