Dataset Information

CccDNA Surrogate MC-HBV-Based Screen Identifies Cohesin Complex as a Novel HBV Restriction Factor.

ABSTRACT:

Background & aims

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV), existing as a stable minichromosome in the hepatocyte, is responsible for persistent HBV infection. Maintenance and sustained replication of cccDNA require its interaction with both viral and host proteins. However, the cccDNA-interacting host factors that limit HBV replication remain elusive.

Methods

Minicircle HBV (MC-HBV), a recombinant cccDNA, was constructed based on chimeric intron and minicircle DNA technology. By mass spectrometry based on pull-down with biotinylated MC-HBV, the cccDNA-hepatocyte interaction profile was mapped. HBV replication was assessed in different cell models that support cccDNA formation.

Results

MC-HBV supports persistent HBV replication and mimics the cccDNA minichromosome. The MC-HBV-based screen identified cohesin complex as a cccDNA binding host factor, leading to reduced HBV replication. Mechanistically, with the help of CCCTC-binding factor (CTCF), which has specific binding sites on cccDNA, cohesin loads on cccDNA and reshapes cccDNA confirmation to prevent RNA polymerase II enrichment. Interestingly, HBV X protein transcriptionally reduces structural maintenance of chromosomes complex expression to partially relieve the inhibitory role of the cohesin complex on HBV replication.

Conclusions

Our data not only provide a feasible approach to explore cccDNA-binding factors, but also identify cohesin/CTCF complex as a critical host restriction factor for cccDNA-driven HBV replication. These findings provide a novel insight into cccDNA-host interaction and targeted therapeutic intervention for HBV infection.

SUBMITTER: Wu Z

PROVIDER: S-EPMC9579331 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

cccDNA Surrogate MC-HBV-Based Screen Identifies Cohesin Complex as a Novel HBV Restriction Factor.

Wu Zhuanchang Z Wang Liyuan L Wang Xin X Sun Yang Y Li Haoran H Zhang Zhaoying Z Ren Caiyue C Zhang Xiaohui X Li Shuangjie S Lu Jinghui J Xu Leiqi L Yue Xuetian X Hong Yue Y Li Qiang Q Zhu Haizhen H Gong Yaoqin Y Gao Chengjiang C Hu Huili H Gao Lifen L Liang Xiaohong X Ma Chunhong C

Cellular and molecular gastroenterology and hepatology 20220817 6

<h4>Background & aims</h4>Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV), existing as a stable minichromosome in the hepatocyte, is responsible for persistent HBV infection. Maintenance and sustained replication of cccDNA require its interaction with both viral and host proteins. However, the cccDNA-interacting host factors that limit HBV replication remain elusive.<h4>Methods</h4>Minicircle HBV (MC-HBV), a recombinant cccDNA, was constructed based on chimeric intron and mini ...[more]

PMID: 35987451

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