title: Single-Molecule Manipulation of the Duplex Formation and Dissociation at the G-Quadruplex/i-Motif Site in the DNA Nanostructure.
abstract: We demonstrate the single-molecule operation and observation of the formation and resolution of double-stranded DNA (dsDNA) containing a G-quadruplex (GQ) forming and counterpart i-motif forming sequence in the DNA nanostructure. Sequential manipulation of DNA strands in the DNA frame was performed to prepare a topologically controlled GQ/i-motif dsDNA. Using strand displacement and the addition and removal of K(+), the topologically controlled GQ/i-motif dsDNA in the DNA frame was obtained in high yield. The dsDNA was resolved into the single-stranded DNA, GQ, and i-motif by the addition of K(+) and operation in acidic conditions. The dissociation of the dsDNA under the GQ and i-motif formation condition was monitored by high-speed atomic force microscopy. The results indicate that the dsDNA containing the GQ- and i-motif sequence is effectively dissolved when the duplex is helically loosened in the DNA nanoscaffold.
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida-ushinomiyacho, Sakyo-ku, Kyoto 606-8501, Japan.|CREST , Japan Science and Technology Corporation (JST), Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Endo
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.|College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University , Wuhan, Hubei 430072, People's Republic of China.
authors.forename: Xiwen
authors.initials: X
authors.lastname: Xing
authors.affiliation: College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University , Wuhan, Hubei 430072, People's Republic of China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Emura
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Kumi
authors.initials: K
authors.lastname: Hidaka
authors.affiliation: Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University , Bangkok 10330, Thailand.
authors.forename: Bodin
authors.initials: B
authors.lastname: Tuesuwan
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida-ushinomiyacho, Sakyo-ku, Kyoto 606-8501, Japan.|Department of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.|CREST , Japan Science and Technology Corporation (JST), Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sugiyama
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry*; D054856:G-Quadruplexes; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology; D011188:Potassium / Q000737:chemistry*
chemical_list: D004277:DNA, Single-Stranded; D004247:DNA; D011188:Potassium
keywords: DNA origami; G-quadruplex; high-speed AFM; i-motif; single-molecule observation