EBNA2 Drives Formation of New Chromosome Binding Sites and Target Genes for B-Cell Master Regulatory Transcription Factors RBP-jκ and EBF1

• Published in: PLoS pathogens 2016, Vol.12 (1), p.e1005339
• Main Authors: Lu, Fang, Chen, Horng-Shen, Kossenkov, Andrew V, DeWispeleare, Karen, Won, Kyoung-Jae, Lieberman, Paul M
• Format: Article
• Language: English
• Subjects: B-Lymphocytes - virology; Blotting, Western; Cell Transformation, Viral - genetics; Chromatin Immunoprecipitation; Epstein-Barr Virus Nuclear Antigens - genetics; Gene Expression Regulation, Viral - genetics; High-Throughput Nucleotide Sequencing; Humans; Immunoglobulin J Recombination Signal Sequence-Binding Protein - genetics; Oligonucleotide Array Sequence Analysis; Polymerase Chain Reaction; Trans-Activators - genetics; Viral Proteins - genetics
• ISSN: 1553-7374; 1553-7366; 1553-7374
• DOI: 10.1371/journal.ppat.1005339

Epstein-Barr Virus (EBV) transforms resting B-lymphocytes into proliferating lymphoblasts to establish latent infections that can give rise to malignancies. We show here that EBV-encoded transcriptional regulator EBNA2 drives the cooperative and combinatorial genome-wide binding of two master regulators of B-cell fate, namely EBF1 and RBP-jκ. Previous studies suggest that these B-cell factors are statically bound to target gene promoters. In contrast, we found that EBNA2 induces the formation of new binding for both RBP-jκ and EBF1, many of which are in close physical proximity in the cellular and viral genome. These newly induced binding sites co-occupied by EBNA2-EBF1-RBP-jκ correlate strongly with transcriptional activation of linked genes that are important for B-lymphoblast function. Conditional expression or repression of EBNA2 leads to a rapid alteration in RBP-jκ and EBF1 binding. Biochemical and shRNA depletion studies provide evidence for cooperative assembly at co-occupied sites. These findings reveal that EBNA2 facilitate combinatorial interactions to induce new patterns of transcription factor occupancy and gene programming necessary to drive B-lymphoblast growth and survival.