title: Quadruplex structures of RNA 14-mer, r(GGAGGUUUUGGAGG) and DNA 14-mer, d(GGAGGTTTTGGAGG).
abstract: We have determined solution structure of r (GGAGGUUUUGGAGG) (R14) by NMR; the RNA 14-mer forms an intra-strand parallel quadruplex with a G-tetrad and a hexad, in which a G-tetrad core is augmented by association of two A residues. The quadruplex further forms a dimer through stacking interaction between the hexads. We also synthesized the corresponding DNA 14-mer, d (GGAGGTTTTGGAGG) (D14), and examined its properties and structure by CD, gel electrophoresis, and NMR. The CD and gel electrophoretic studies suggest that D14 forms a quadruplex entirely different from that of R14 in the presence of K+ ions; two molecules of D14 form a quadruplex containing antiparalle strands and diagonal loops. The NMR study also gave the results that are consistent with such structure: alternate glycosidic conformation, 5'G(syn)-G(anti)3', and characteristic chemical shift data.
authors.affiliation: Department of Environment and Natural Sciences, Graduate School of Environment and Information Sciences, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama, 240-8501, Japan.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kugimiya
authors.forename: Akimasa
authors.initials: A
authors.lastname: Matsugami
authors.forename: Masato
authors.initials: M
authors.lastname: Katahira
authors.forename: Seiichi
authors.initials: S
authors.lastname: Uesugi
mesh_terms: D001483:Base Sequence; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D012313:RNA / Q000737:chemistry*
chemical_list: D012313:RNA; D004247:DNA