title: Padlock oligonucleotides for duplex DNA based on sequence-specific triple helix formation.
abstract: An oligonucleotide was circularized around double-stranded DNA thanks to triple helix formation. Short oligonucleotides are known to be able to form DNA triple helices by binding into the DNA major groove at an oligopurine.oligopyrimidine sequence. After sequence-specific recognition of a double-stranded DNA target through triple helix formation, the ends of the triplex-forming oligonucleotide were joined through the action of T4 DNA ligase, thus creating a circular DNA molecule catenated to the plasmid containing the target sequence. The labeling of the double-stranded DNA sequence has been carried out without any chemical or enzymatic modification of this sequence. These "padlock" oligonucleotides provide a tool to attach a noncovalent tag in an irreversible way to supercoiled plasmid or other double-stranded DNAs. Such a complex may find applications in the development of new techniques for duplex DNA detection or plasmid delivery methods for gene therapy.
authors.affiliation: Laboratoire de Biophysique, Muséum National d'Histoire Naturelle, Institut National de la Santé et de la Recherche Médicale Unité 201, Centre National de la Recherche Scientifique, 43, rue Cuvier, 75231 Paris, France. escude@mnhn.fr
authors.forename: C
authors.initials: C
authors.lastname: Escudé
authors.forename: T
authors.initials: T
authors.lastname: Garestier
authors.forename: C
authors.initials: C
authors.lastname: Hélène
mesh_terms: D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000737:chemistry / Q000235:genetics*; D004270:DNA, Circular / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D051379:Mice; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000737:chemistry / Q000235:genetics*; D010957:Plasmids; D011944:Receptors, Androgen / Q000235:genetics
chemical_list: D004270:DNA, Circular; D009841:Oligonucleotides; D011944:Receptors, Androgen; C051802:triplex DNA; D004247:DNA