title: A potent 2'-O-methylated RNA-based microRNA inhibitor with unique secondary structures.
abstract: MicroRNAs (miRNAs) are involved in various biological processes and human diseases. The development of strong low-molecular weight inhibitors of specific miRNAs is thus expected to be useful in providing tools for basic research or in generating promising new therapeutic drugs. We have previously described the development of 'Tough Decoy (TuD) RNA' molecules, which achieve the long-term suppression of specific miRNA activity in mammalian cells when expressed from a lentivirus vector. In our current study, we describe new synthetic miRNA inhibitors, designated as S-TuD (Synthetic TuD), which are composed of two fully 2'-O-methylated RNA strands. Each of these strands includes a miRNA-binding site. Following the hybridization of paired strands, the resultant S-TuD forms a secondary structure with two stems, which resembles the corresponding TuD RNA molecule. By analyzing the effects of S-TuD against miR-21, miR-200c, miR-16 and miR-106b, we have elucidated the critical design features of S-TuD molecules that will provide optimum inhibitory effects following transfection into human cell lines. We further show that the inhibitory effects of a single transfection of S-TuD-miR200c are quite long-lasting (>7 days) and induce partial EMT, the full establishment of which requires 11 days when using a lentivirus vector that expresses TuD-miR200c continuously.
authors.affiliation: Division of Host-Parasite Interaction, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Haraguchi
authors.forename: Haruo
authors.initials: H
authors.lastname: Nakano
authors.forename: Takanobu
authors.initials: T
authors.lastname: Tagawa
authors.forename: Tokimitsu
authors.initials: T
authors.lastname: Ohki
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ueno
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Yoshida
authors.forename: Hideo
authors.initials: H
authors.lastname: Iba
mesh_terms: D001665:Binding Sites; D045744:Cell Line, Tumor; D058750:Epithelial-Mesenchymal Transition; D006801:Humans; D035683:MicroRNAs / Q000037:antagonists & inhibitors* / Q000737:chemistry; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D012313:RNA / Q000737:chemistry* / Q000378:metabolism; D014162:Transfection
chemical_list: D035683:MicroRNAs; D012313:RNA