CEP290 is Associated With Chromatin Accessibility of Hepatitis B virus cccDNA.

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) serves as a stable nuclear template for viral transcription, yet the mechanisms controlling its chromatin accessibility remain poorly understood. Here, we performed single-cell assay for transposase-accessible chromatin sequencing (ATAC-seq) in HBV-infected human hepatocytes to profile cccDNA chromatin states. We identified discrete closed regions within cccDNA, while a subset of cells exhibited open chromatin at these loci, accompanied by elevated CEP290 (centrosomal protein 290) and several additional genes. Functional studies using CRISPR/Cas9-mediated knockdown or CRISPR-based transcriptional activation demonstrated that CEP290 positively regulates cccDNA and total HBV DNA levels. Combining CEP290 knockdown with entecavir or HBV-targeting siRNA further reduced cccDNA, although complete elimination was not achieved. Bulk ATAC-seq demonstrated that CEP290 influences chromatin accessibility at selected cccDNA regions and affects host genomic loci. Taken together, our findings suggest that CEP290, along with other gene candidates identified from regions of sporadically opened cccDNA chromatin, may influence HBV cccDNA regulation and viral replication. These results illustrate that single-cell chromatin profiling can reveal host factors potentially involved in HBV persistence.