Phosphorylation of Epstein-Barr virus ZEBRA protein at its casein kinase 2 sites mediates its ability to repress activation of a viral lytic cycle late gene by Rta.

Viral Lytic Cycle Late Gene by Rta Mediates Its Ability To Repress Activation ZEBRA Protein at Its Casein Kinase 2 Sites Phosphorylation of Epstein-Barr Virus

Lytic cycle switches of oncogenic human gammaherpesviruses.

The seminal experiments of George and Eva Klein helped to define the two life cycles of Epstein-Barr Virus (EBV), namely latency and lytic or productive infection. Their laboratories described latent nuclear antigens expressed during latency and discovered several chemicals that activated the viral lytic cycle. The mechanism of the switch between latency and the lytic cycle of EBV and Kaposi's ...

Serine-173 of the Epstein-Barr virus ZEBRA protein is required for DNA binding and is a target for casein kinase II phosphorylation.

An Epstein-Barr virus-encoded protein, ZEBRA, mediates the switch from latency to the viral lytic life cycle. ZEBRA's domain structure and DNA binding specificity resemble that of cellular transcriptional activators such as c-Fos/c-Jun. We show that ZEBRA, like c-Jun, is phosphorylated by casein kinase II (CKII). The principal site of phosphorylation is serine-173 (S173), five amino acids upstr...

The Epstein-Barr virus Rta protein activates lytic cycle genes and can disrupt latency in B lymphocytes.

The transition of Epstein-Barr virus (EBV) from latency into the lytic cycle is associated with the expression of two immediate-early viral genes, BZLF1 and BRLF1. Overexpression of ZEBRA, the product of BZLF1, is sufficient to disrupt latency in B lymphocytes and epithelial cells by stimulating expression of lytic cycle genes, including BRLF1. The BRLF1 product Rta functions as a transcription...

Autostimulation of the Epstein-Barr virus BRLF1 promoter is mediated through consensus Sp1 and Sp3 binding sites.

As an essential step in the lytic cascade, the Rta homologues of gammaherpesviruses all activate their own expression. Consistent with this biologic function, the Epstein-Barr virus (EBV) Rta protein powerfully stimulates the promoter of its own gene, Rp, in EBV-positive B cells in transient-transfection reporter-based assays. We analyzed the activity of RpCAT in response to Rta by deletional a...