title: SiRNAs conjugated with aromatic compounds induce RISC-mediated antisense strand selection and strong gene-silencing activity.
abstract: Short interference RNA (siRNA) is a powerful tool for suppressing gene expression in mammalian cells. In this study, we focused on the development of siRNAs conjugated with aromatic compounds in order to improve the potency of RNAi and thus to overcome several problems with siRNAs, such as cellular delivery and nuclease stability. The siRNAs conjugated with phenyl, hydroxyphenyl, naphthyl, and pyrenyl derivatives showed strong resistance to nuclease degradation, and were thermodynamically stable compared with unmodified siRNA. A high level of membrane permeability in HeLa cells was also observed. Moreover, these siRNAs exhibited enhanced RNAi efficacy, which exceeded that of locked nucleic acid (LNA)-modified siRNAs, against exogenous Renilla luciferase in HeLa cells. In particular, abundant cytoplasmic localization and strong gene-silencing efficacy were found in the siRNAs conjugated with phenyl and hydroxyphenyl derivatives. The novel siRNAs conjugated with aromatic compounds are promising candidates for a new generation of modified siRNAs that can solve many of the problems associated with RNAi technology.
authors.affiliation: Faculty of Pharmacy, Yasuda Women's University, 6-13-1 Yasuhigashi, Asaminami-ku, Hiroshima 731-0153, Japan. kubo-t@yasuda-u.ac.jp
authors.forename: Takanori
authors.initials: T
authors.lastname: Kubo
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Yanagihara
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Takei
authors.forename: Keichiro
authors.initials: K
authors.lastname: Mihara
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Sato
authors.forename: Toshio
authors.initials: T
authors.lastname: Seyama
mesh_terms: D006367:HeLa Cells; D006801:Humans; D006841:Hydrocarbons, Aromatic / Q000737:chemistry / Q000494:pharmacology*; D049410:Luciferases, Renilla / Q000235:genetics; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000737:chemistry / Q000494:pharmacology*; D034743:RNA-Induced Silencing Complex / Q000378:metabolism*
chemical_list: D006841:Hydrocarbons, Aromatic; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex; D049410:Luciferases, Renilla