title: Stable triple helices formed by oligonucleotide N3'-->P5' phosphoramidates inhibit transcription elongation.
abstract: Oligonucleotide analogs with N3'-->P5' phosphoramidate linkages bind to the major groove of double-helical DNA at specific oligopurine.oligopyrimidine sequences. These triple-helical complexes are much more stable than those formed by oligonucleotides with natural phosphodiester linkages. Oligonucleotide phosphoramidates containing thymine and cytosine or thymine, cytosine, and guanine bind strongly to the polypurine tract of human immunodeficiency virus proviral DNA under physiological conditions. Site-specific cleavage by the Dra I restriction enzyme at the 5' end of the polypurine sequence was inhibited by triplex formation. A eukaryotic transcription assay was used to investigate the effect of oligophosphoramidate binding to the polypurine tract sequence on transcription of the type 1 human immunodeficiency virus nef gene under the control of a cytomegalovirus promoter. An efficient arrest of RNA polymerase II was observed at the specific triplex site at submicromolar concentrations.
authors.affiliation: Laboratoire de Biophysique, Muséum National d'Histoire Naturelle, Institut National de la Santé et de la Recherche Médicale, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Escudé
authors.forename: C
authors.initials: C
authors.lastname: Giovannangeli
authors.forename: J S
authors.initials: JS
authors.lastname: Sun
authors.forename: D H
authors.initials: DH
authors.lastname: Lloyd
authors.forename: J K
authors.initials: JK
authors.lastname: Chen
authors.forename: S M
authors.initials: SM
authors.lastname: Gryaznov
authors.forename: T
authors.initials: T
authors.lastname: Garestier
authors.forename: C
authors.initials: C
authors.lastname: Hélène
mesh_terms: D000577:Amides; D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology*; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003587:Cytomegalovirus / Q000235:genetics; D004247:DNA / Q000737:chemistry; D015754:Genes, nef; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry / Q000494:pharmacology*; D010756:Phosphoric Acids; D011401:Promoter Regions, Genetic; D013816:Thermodynamics; D014158:Transcription, Genetic / Q000187:drug effects*
chemical_list: D000577:Amides; D000998:Antiviral Agents; D009838:Oligodeoxyribonucleotides; D010756:Phosphoric Acids; D004247:DNA; C011067:phosphoramidic acid