title: Inhibition of HIV-1 replication by a two-strand system (FTFOs) targeted to the polypurine tract.
abstract: Reverse transcription of HIV-1 vRNA into the double-stranded DNA provirus involves initiation of plus-strand DNA synthesis at the polypurine tract (PPT) by reverse transcriptase (RT). The PPT is highly conserved among the known human immunodeficiency virus (HIV-1) strains and is a possible target for triplex formation. We show the effects of triple-helix formation by assays of primer extension inhibition in vitro, using a two-strand system (foldback triplex-forming oligonucleotides (FTFOs)) targeted to the PPT of HIV-1. The two-stranded composition of a triple-helix is thermodynamically and kinetically superior to the three-strand system. The FTFOs inhibited the RT activity in a sequence-specific manner, i.e. the triplex actually formed at the PPT and blocked the RT. The FTFOs containing the phosphorothioate groups at the antisense sequences showed greater 3'-exonuclease resistance. In HIV-1-infected MOLT-4 cells, the FTFOs containing the phosphorothioate groups at the antisense sequence sites and guanosine rich parts within the third Hoogsteen base-pairing sequence inhibit the replication of HIV-1 more effectively than the antisense oligonucleotides, indicating sequence-specific inhibition of HIV-1 replication.
authors.affiliation: Department of Industrial Chemistry, Chiba Institute of Technology, Narashino, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hiratou
authors.forename: S
authors.initials: S
authors.lastname: Tsukahara
authors.forename: N
authors.initials: N
authors.lastname: Miyano-Kurosaki
authors.forename: K
authors.initials: K
authors.lastname: Takai
authors.forename: N
authors.initials: N
authors.lastname: Yamamoto
authors.forename: H
authors.initials: H
authors.lastname: Takaku
mesh_terms: D019380:Anti-HIV Agents / Q000737:chemistry / Q000494:pharmacology; D001483:Base Sequence; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors; D015497:HIV-1 / Q000187:drug effects*; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000737:chemistry* / Q000494:pharmacology*; D016376:Oligonucleotides, Antisense / Q000737:chemistry / Q000494:pharmacology*; D011687:Purines / Q000737:chemistry; D018894:Reverse Transcriptase Inhibitors / Q000737:chemistry / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects / Q000821:virology; D013873:Thionucleotides / Q000737:chemistry / Q000494:pharmacology; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D019380:Anti-HIV Agents; D009841:Oligonucleotides; D016376:Oligonucleotides, Antisense; D011687:Purines; D018894:Reverse Transcriptase Inhibitors; D013873:Thionucleotides; D054303:HIV Reverse Transcriptase