Epstein-Barr Virus episome physically interacts with active regions of the host genome in lymphoblastoid cells
Epstein-Barr virus (EBV) episome is known to interact with the three-dimensional structure of human genome in infected cells. However, the exact locations of these interactions and their potential functional consequences remain unclear. Recently the high-resolution chromatin interaction capture (Hi-C) assays in lymphoblastoid cells have become available enabling us to precisely map the contacts between the EBV episome(s) and the human host genome. Using available Hi-C data at 10kb resolution, we have identified nearly 15000 reproducible contacts between EBV episome and human genome. These contacts are highly enriched in chromatin regions denoted by typical or super enhancers and active marks including histone H3 K27ac, K4me1, K79me2 and K4me2. Additionally, these contacts are highly enriched at loci bound by host transcription factors that regulate B cell growth (e.g. IKZF1 and RUNX3), factors that enhance cell proliferation (e.g. HDGF) or factors that promote viral replication (e.g. NBS1 and NFIC). EBV contacts show nearly two-fold enrichment in host regions bound by EBV EBNA2 and EBNA3B transcription factors. Chromosome conformation capture coupled with sequencing (4C-seq) using the EBV oriP as a “bait” loci in lymphoblastoid cells further confirmed contact with active chromatin regions. Collectively, our analysis supports the interaction between EBV episome(s) and active regions of human genome in lymphoblastoid cells. Overall design: Epstein-Barr virus (EBV) genomes persist in latently infected cells as extrachromosomal molecules that attach to host chromosomes through a viral encoded sequence-specific DNA binding protein. We employed circular chromosome conformation capture (4C) analysis to identify genomewide associations between EBV episomes and host chromosomes.