title: Human DNA topoisomerase I-mediated cleavage and recombination of duck hepatitis B virus DNA in vitro.
abstract: In this study, we report that eukaryotic topoisomerase I (top1) can linearize the open circular DNA of duck hepatitis B virus (DHBV). Using synthetic oligonucleotides mimicking the three-strand flap DR1 region of the DHBV genome, we found that top1 cleaves the DNA plus strand in a suicidal manner, which mimics the linearization of the virion DNA. We also report that top1 can cleave the DNA minus strand at specific sites and can linearize the minus strand via a non-homologous recombination reaction. These results are consistent with the possibility that top1 can act as a DNA endo-nuclease and strand transferase and play a role in the circularization, linearization and possibly integration of viral replication intermediates.
authors: Laboratory of Molecular Pharmacology, Building 37, Room 5D02, Division of Basic Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4255, USA.
authors: P
authors: P
authors: Pourquier
authors: A D
authors: AD
authors: Jensen
authors: S S
authors: SS
authors: Gong
authors: Y
authors: Y
authors: Pommier
authors: C E
authors: CE
authors: Rogler
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002645:Chickens; D002874:Chromosome Mapping; D004264:DNA Topoisomerases, Type I / Q000378:metabolism*; D004277:DNA, Single-Stranded; D004279:DNA, Viral / Q000378:metabolism*; D004372:Ducks / Q000821:virology; D015611:Hepatitis B Virus, Duck / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D014407:Tumor Cells, Cultured; D014771:Virion
chemical_list: D004277:DNA, Single-Stranded; D004279:DNA, Viral; D004264:DNA Topoisomerases, Type I