title: DNA-binding activity of rat DNA topoisomerase II α C-terminal domain contributes to efficient DNA catenation in vitro.
abstract: DNA topoisomerase IIα (topo IIα) is an essential enzyme for resolution of DNA topologies arising in DNA metabolic reactions. In proliferating cells, topo II activities of DNA catenation or decatenation are required for condensation of chromosomes and segregation of chromatids. Recent studies suggest that the C-terminal domain (CTD) of human topo IIα is required for localization to mitotic chromosomes. Here, we show that the CTD of topo IIα is also associated with efficient DNA catenation in vitro, based on comparison of wild-type (WT) rat topo IIα and its deletion mutants. Unlike WT, the CTD truncated mutant (ΔCTD) lacked linear DNA binding activity, but could bind to negatively supercoiled DNA similarly to WT. The CTD alone showed linear DNA-binding activity. ΔCTD mediated formation of a DNA catenane in the presence of polyethylene glycol, which enhances macromolecular association. These results indicate that DNA-binding activity in the CTD of topo IIα concentrates the enzyme in the vicinity of condensed DNA and allows topo IIα to efficiently form a DNA catenane.
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan and kawanos@dbc.ous.ac.jp.
authors.forename: Shinji
authors.initials: S
authors.lastname: Kawano
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan and.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan and.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Okada
authors.affiliation: Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Sano
authors.affiliation: Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Tsutsui
authors.affiliation: Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Kimiko M
authors.initials: KM
authors.lastname: Tsutsui
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan and.
authors.forename: Shogo
authors.initials: S
authors.lastname: Ikeda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000951:Antigens, Neoplasm / Q000737:chemistry* / Q000235:genetics; D004250:DNA Topoisomerases, Type II / Q000737:chemistry* / Q000235:genetics; D043864:DNA, Catenated / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D011092:Polyethylene Glycols / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D051381:Rats; D017384:Sequence Deletion
chemical_list: D000951:Antigens, Neoplasm; D043864:DNA, Catenated; D004268:DNA-Binding Proteins; D011092:Polyethylene Glycols; D004250:DNA Topoisomerases, Type II
keywords: C-terminal domain; DNA-binding; catenation; topoisomerase II; α isoform