Genome-wide analysis of histone methylation reveals chromatin state-based regulation of host cellular gene expression induced by hepatitis B viruses (DGE dataset)

Hepatitis B virus (HBV) is a hepatotropic virus that can regulate many host cellular gene expressions participating in the HBV life cycle, liver inflammation and hepatocellular injury. However, the underlying mechanism of differential gene expression is not understood. We report here a genome-wide analysis of histone methylation on two histone H3 lysine residues (H3K4me3 and H3K27me3) and gene expression profiles in HepG2 and HepG2.2.15 cells. We found that specific correlation exists between gene expression and the amounts of H3K4me3 (positive correlation) and H3K27me3 (negative correlation) across the gene body. These correlations displayed three distinct modes (repressive, active and poised), reflecting different functions of these genes in the HBV life cycle, liver inflammation and hepatocellular injury. Furthermore, a permissive chromatin state of each gene was established by a combination of different histone modifications. Our findings reveal a complex regulation by histone methylation in differential gene expression and suggest that histone methylation may be responsible for the HBV life cycle, liver inflammation and hepatocellular injury induced by HBV. Overall design: A large-scale analysis of gene expression of 2 different cell types (HepG2, HepG2.2.15) using a digital gene expression (DGE) tag profiling approach.

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Tian Y, Ni D, Yang W, Zhang Y, Zhao K, Song J, Mao Q, Tian Z, van Velkinburgh JC, Yang D, Wu Y, Ni B