title: Kinetic study of the binding of triplex-forming oligonucleotides containing partial cationic modifications to double-stranded DNA.
abstract: Several triplex-forming oligonucleotides (TFOs) partially modified with 2'-O-(2-aminoethyl)- or 2'-O-(2-guanidinoethyl)-nucleotides were synthesized and their association rate constants (kon) with double-stranded DNA were estimated by UV spectrophotometry. Introduction of cationic modifications in the 5'-region of the TFOs significantly increased the kon values compared to that of natural TFO, while no enhancement in the rate of triplex DNA formation was observed when the modifications were in the middle and at the 3'-region. The kon value of a TFO with three adjacent cationic modifications at the 5'-region was found to be 3.4 times larger than that of a natural one. These results provide useful information for overcoming the inherent sluggishness of triplex DNA formation.
authors.affiliation: Graduate School of Phamaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita 565-0871, Japan. Electronic address: hari@phs.osaka-u.ac.jp.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Hari
authors.affiliation: Graduate School of Phamaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita 565-0871, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Ijitsu
authors.affiliation: Graduate School of Phamaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita 565-0871, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Akabane-Nakata
authors.affiliation: Graduate School of Phamaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita 565-0871, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Yoshida
authors.affiliation: Graduate School of Phamaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita 565-0871, Japan. Electronic address: obika@phs.osaka-u.ac.jp.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Obika
mesh_terms: D001665:Binding Sites; D002412:Cations / Q000737:chemistry; D004247:DNA / Q000138:chemical synthesis / Q000737:chemistry*; D007700:Kinetics; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000737:chemistry*
chemical_list: D002412:Cations; D009841:Oligonucleotides; C051802:triplex DNA; D004247:DNA
keywords: Kinetic studies; Modified nucleotides; Oligonucleotides; Triplex DNA; Triplex-forming oligonucleotides