The role of host DNA ligases in hepadnavirus covalently closed circular DNA formation
| Autor: | Elena S. Kim, Soujuan Wang, Dawei Cai, Ailong Huang, Bidisha Mitra, Hu Zhang, Jie-Li Hu, Ran Yan, Quanxin Long, Yuanjie Liu, Haitao Guo, Alexander Marchetti |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
DNA Repair Artificial Gene Amplification and Extension Hepadnaviridae LIG1 Biochemistry Polymerase Chain Reaction Electrophoretic Blotting Ligases DNA Ligase ATP Gene Knockout Techniques chemistry.chemical_compound Poly-ADP-Ribose Binding Proteins DNA extraction lcsh:QH301-705.5 Gel Electrophoresis chemistry.chemical_classification Chemistry Hep G2 Cells cccDNA Enzymes 3. Good health Cell biology Nucleic acids Gene Knockdown Techniques Host-Pathogen Interactions Hepadnavirus DNA Circular Metabolic Networks and Pathways Research Article lcsh:Immunologic diseases. Allergy Hepatitis B virus DNA Ligases DNA repair Immunology Molecular Probe Techniques DNA construction DNA replication Research and Analysis Methods Microbiology Cell Line Electrophoretic Techniques 03 medical and health sciences Extraction techniques Virology Genetics Humans Molecular Biology Techniques Molecular Biology DNA ligase Biology and life sciences Proteins DNA HEK293 Cells 030104 developmental biology lcsh:Biology (General) Plasmid Construction DNA Viral Enzymology Hepatocytes Parasitology lcsh:RC581-607 Southern Blot |
| Zdroj: | PLoS Pathogens, Vol 13, Iss 12, p e1006784 (2017) PLoS Pathogens |
| ISSN: | 1553-7374 1553-7366 |
| Popis: | Hepadnavirus covalently closed circular (ccc) DNA is the bona fide viral transcription template, which plays a pivotal role in viral infection and persistence. Upon infection, the non-replicative cccDNA is converted from the incoming and de novo synthesized viral genomic relaxed circular (rc) DNA, presumably through employment of the host cell’s DNA repair mechanisms in the nucleus. The conversion of rcDNA into cccDNA requires preparation of the extremities at the nick/gap regions of rcDNA for strand ligation. After screening 107 cellular DNA repair genes, we herein report that the cellular DNA ligase (LIG) 1 and 3 play a critical role in cccDNA formation. Ligase inhibitors or functional knock down/out of LIG1/3 significantly reduced cccDNA production in an in vitro cccDNA formation assay, and in cccDNA-producing cells without direct effect on viral core DNA replication. In addition, transcomplementation of LIG1/3 in the corresponding knock-out or knock-down cells was able to restore cccDNA formation. Furthermore, LIG4, a component in non-homologous end joining DNA repair apparatus, was found to be responsible for cccDNA formation from the viral double stranded linear (dsl) DNA, but not rcDNA. In conclusion, we demonstrate that hepadnaviruses utilize the whole spectrum of host DNA ligases for cccDNA formation, which sheds light on a coherent molecular pathway of cccDNA biosynthesis, as well as the development of novel antiviral strategies for treatment of hepatitis B. Author summary Hepadnavirus cccDNA is the persistent form of viral genome, and in terms of human hepatitis B virus (HBV), cccDNA is the basis for viral rebound after the cessation of therapy, as well as the elusiveness of a cure with current medications. Therefore, the elucidation of molecular mechanism of cccDNA formation will aid HBV research at both basic and medical levels. In this study, we screened a total of 107 cellular DNA repair genes and identified DNA ligase 1 and 3 as key factors for cccDNA formation from viral relaxed (open) circular DNA. In addition, we found that the cellular DNA ligase 4 is responsible for converting viral double-stranded linear DNA into cccDNA. Our study further confirmed the involvement of host DNA repair machinery in cccDNA formation, and may reveal new antiviral targets for treatment of hepatitis B in future. |
| Databáze: | OpenAIRE |
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