Promoter targeted histone acetylation of chromatinized parvoviral genome is essential for infrection progress

The association of host histones with parvoviral DNA is poorly understood. We analyzed the chromatinization and histone acetylation of canine parvovirus DNA during infection by confocal imaging and in situ proximity ligation assay combined with chromatin immunoprecipitation and high-throughput sequencing. We found that at late infection parvovirus replication bodies were rich in histones bearing modifications characteristic of transcriptionally active chromatin, i.e. histone H3 lysine acetylation (H3K27ac). The H3K27ac, in particular, was located in close proximity to the viral DNA-binding protein NS1. Importantly, our results show for the first time that in the chromatinized parvoviral genome, particularly the two viral promoters were rich in H3K27ac. Histone acetyltransferase (HAT) inhibitorefficiently interfered with expression of viral proteins and infection progress. Altogether, our data suggest that acetylation of histones on parvoviral DNA is essential for viral gene expression and completion of viral life cycle. Examination of H3K27 acetylation in CPV infected and non-infected NLFK (Norden laboratory feline kidney) cells. Please note that the result in this study, considering the sequencing, is the fact that the viral genome is chromatinized. Processed data in this case would be the aligned read percentages in control cells (of which 0% aligns to parvoviral genome) and infected cells (of which ~9% only aligns to parvoviral genome and not to the cat genome), which is basically the output of the read aligner software without further processing steps (no peaks or regions were identified for the associated publication). Therefore no processed data was provided, and an exception to GEO processed data requirement was made.