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Hepatitis B is caused by hepatitis B virus (HBV), and persistent HBV infection is a global public health problem, with 257 million people as HBV chronic carriers. Viral covalently closed circular DNA (cccDNA) is a key factor to establish persistent infection in infected hepatocytes. Current antiviral therapies have no direct impact on pre-existing cccDNA reservoir, which can be assembled into minichromosome by hijacking host factors. Understanding the mechanisms of epigenetic regulation in cccDNA minichromosome is crucial to develop new therapy on cccDNA, an attractive target for HBV cure. This review summarizes the current advances in epigenetic regulation of cccDNA minichromosome, which might provide clues to novel druggable targets to cure hepatitis B by either silencing or eliminating cccDNA reservoir.

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Epigenetic regulation of covalently closed circular DNA minichromosome in hepatitis B virus infection

Show Author's information Zhaoning Wang1,2Weiwei Wang2Lanfeng Wang2( )
School of Life Sciences, Shanghai University, Shanghai 200444, China
The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China


Hepatitis B is caused by hepatitis B virus (HBV), and persistent HBV infection is a global public health problem, with 257 million people as HBV chronic carriers. Viral covalently closed circular DNA (cccDNA) is a key factor to establish persistent infection in infected hepatocytes. Current antiviral therapies have no direct impact on pre-existing cccDNA reservoir, which can be assembled into minichromosome by hijacking host factors. Understanding the mechanisms of epigenetic regulation in cccDNA minichromosome is crucial to develop new therapy on cccDNA, an attractive target for HBV cure. This review summarizes the current advances in epigenetic regulation of cccDNA minichromosome, which might provide clues to novel druggable targets to cure hepatitis B by either silencing or eliminating cccDNA reservoir.

Keywords: HBV, Epigenetic regulation, cccDNA, Minichromosome


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Publication history
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Publication history

Received: 17 April 2020
Accepted: 25 May 2020
Published: 25 July 2020
Issue date: August 2020


© The Author(s) 2020



We thank Prof. Yu Wei (Institut Pasteur of Shanghai, CAS) for her constructive comment. We apologize to scientists in this field, whose publications were not cited due to space limit. This work was supported by the Strategic Priority Research Program of CAS (XDB29010205), the National Key R&D Program of China (2018YFA0507303, 2018YFC1200701), and National Natural Science Foundation of China (31770816).

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