title: Modulation of highly ordered structures of human telomeric sequence by cationic copolymers.
abstract: Human telomeric DNA, d(GGGTTA)n, tends to adopt complex intramolecular G-quadruplex structure in solution. The sequence folds into G-quadruplex with the antiparallel orientation in the presence of sodium ions, while antiparallel and parallel conformations were coexisted in solution containing relatively high concentration of potassium ions. Here, we describe that cationic comb-type copolymer, poly(l-lysine)-graft-dextran (PLL-g-Dex), triggers selective folding of d[GGG(TTAGGG)3] into G-quadruplex with the parallel orientation. The parallel G-quadruplex formed in the presence of the copolymer has the melting temperature > 90 degrees C, including strong stabilization effect of the copolymer.
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori, Yokohama 226-8501, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Makita
authors.forename: Arihiro
authors.initials: A
authors.lastname: Kano
authors.forename: Asako
authors.initials: A
authors.lastname: Yamayoshi
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Akaike
authors.forename: Atsushi
authors.initials: A
authors.lastname: Maruyama
mesh_terms: D001483:Base Sequence; D002412:Cations / Q000737:chemistry; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D003911:Dextrans / Q000737:chemistry*; D054856:G-Quadruplexes; D006147:Guanine / Q000737:chemistry; D006801:Humans; D011107:Polylysine / Q000031:analogs & derivatives* / Q000737:chemistry; D012091:Repetitive Sequences, Nucleic Acid; D016615:Telomere / Q000737:chemistry*
chemical_list: D002412:Cations; D003911:Dextrans; C113090:poly(lysine)-graft-dextran; D011107:Polylysine; D006147:Guanine; D004247:DNA