title: Binding and dissociation of human topoisomerase I with hairpin-loop RNAs: implications for the regulation of HIV-1 replication.
abstract: Cellular topoisomerase I has been reported to be present in retroviral particles and to enhance viral cDNA synthesis; however, the mechanisms involved remain unknown. In the present study, it has been demonstrated that human topoisomerase I combines with a stem-loop RNA and that the bound topoisomerase I can be dissociated from RNA substrates in the presence of ATP. In addition, in vitro cleaved synthetic RNA bound by topoisomerase I is subsequently relegated when the topoisomerase I is dissociated by ATP. A mechanism is proposed in which human topoisomerase I is carried into virions and regulates the repair of genomic RNA by its ligation activity.
authors.affiliation: Department of Pathology, National Institute of Infectious Diseases, Toyama 1-23-1, Shinjuku-ku, Tokyo 162-8640, Japan. htakahas@nih.go.jp
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Takahashi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Sawa
authors.forename: Hideki
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Tetsutaro
authors.initials: T
authors.lastname: Sata
authors.forename: William
authors.initials: W
authors.lastname: Hall
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kurata
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers; D004261:DNA Replication; D004264:DNA Topoisomerases, Type I / Q000737:chemistry* / Q000378:metabolism*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012367:RNA, Viral / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D014158:Transcription, Genetic; D014771:Virion / Q000201:enzymology / Q000235:genetics; D014779:Virus Replication / Q000502:physiology*
chemical_list: D017931:DNA Primers; D012367:RNA, Viral; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D004264:DNA Topoisomerases, Type I