title: PRMT5 restricts hepatitis B virus replication through epigenetic repression of covalently closed circular DNA transcription and interference with pregenomic RNA encapsidation.
abstract: Chronic hepatitis B virus (HBV) infection remains a major health problem worldwide. The covalently closed circular DNA (cccDNA) minichromosome, which serves as the template for the transcription of viral RNAs, plays a key role in viral persistence. While accumulating evidence suggests that cccDNA transcription is regulated by epigenetic machinery, particularly the acetylation of cccDNA-bound histone 3 (H3) and H4, the potential contributions of histone methylation and related host factors remain obscure. Here, by screening a series of methyltransferases and demethylases, we identified protein arginine methyltransferase 5 (PRMT5) as an effective restrictor of HBV transcription and replication. In cell culture-based models for HBV infection and in liver tissues of patients with chronic HBV infection, we found that symmetric dimethylation of arginine 3 on H4 on cccDNA was a repressive marker of cccDNA transcription and was regulated by PRMT5 depending on its methyltransferase domain. Moreover, PRMT5-triggered symmetric dimethylation of arginine 3 on H4 on the cccDNA minichromosome involved an interaction with the HBV core protein and the Brg1-based human SWI/SNF chromatin remodeler, which resulted in down-regulation of the binding of RNA polymerase II to cccDNA. In addition to the inhibitory effect on cccDNA transcription, PRMT5 inhibited HBV core particle DNA production independently of its methyltransferase activity. Further study revealed that PRMT5 interfered with pregenomic RNA encapsidation by preventing its interaction with viral polymerase protein through binding to the reverse transcriptase-ribonuclease H region of polymerase, which is crucial for the polymerase-pregenomic RNA interaction.
  
  
  
  PRMT5 restricts HBV replication through a two-part mechanism including epigenetic suppression of cccDNA transcription and interference with pregenomic RNA encapsidation; these findings improve the understanding of epigenetic regulation of HBV transcription and host-HBV interaction, thus providing new insights into targeted therapeutic intervention. (Hepatology 2017;66:398-415).
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.|Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Jieliang
authors.initials: J
authors.lastname: Chen
authors.affiliation: Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.affiliation: Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.|Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Yue
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Jiangxia
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Baocun
authors.initials: B
authors.lastname: Li
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Shen
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Bai
authors.affiliation: Institute of Virology, Technische Universität München/Helmholtz Zentrum München, Munich, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Protzer
authors.affiliation: Cancer Research Center of Lyon, INSERM U1052, Lyon, France.
authors.forename: Massimo
authors.initials: M
authors.lastname: Levrero
authors.affiliation: Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Zhenghong
authors.initials: Z
authors.lastname: Yuan
mesh_terms: D001707:Biopsy, Needle; D015139:Blotting, Southern / Q000379:methods; D002478:Cells, Cultured; D004261:DNA Replication / Q000235:genetics*; D004270:DNA, Circular / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D057890:Epigenomics / Q000379:methods; D056945:Hep G2 Cells / Q000166:cytology / Q000378:metabolism; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000235:genetics / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D011484:Protein-Arginine N-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D046509:Tissue Culture Techniques; D014158:Transcription, Genetic / Q000235:genetics*; D019562:Viral Load / Q000235:genetics; D014779:Virus Replication / Q000235:genetics*
chemical_list: D004270:DNA, Circular; D004279:DNA, Viral; C400529:PRMT5 protein, human; D011484:Protein-Arginine N-Methyltransferases