title: Inhibition of translation by small RNA-stabilized mRNA structures in human cells.
abstract: RNA-mediated gene regulation and expression are critically dependent on both nucleic acid architecture and recognition. We present a novel mechanism for the regulation of gene expression through direct RNA-RNA interactions between small RNA and mRNA in human cells. Using mRNA reporters containing G-rich sequences in the 5'-untranslated region (5'-UTR), in the coding region, or both, we showed that G-rich small RNAs bind to the reporter mRNAs and form an intermolecular RNA G-quadruplex that can inhibit gene translation in living cells. Using a combination of circular dichroism (CD) and RNase footprinting in vitro, we found that the intermolecular G-quadruplexes show a parallel G-quadruplex structure. We next investigated whether the intermolecular G-quadruplex is present in living cells. Employing the fluorophore-labeled probes, we found that two G-rich RNA molecules form an intermolecular G-quadruplex structure in living cells. These results extend the concept of small RNA-mediated expression and suggest an important role for such RNA structures in the inhibition of mRNA translation.
authors: Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan.
authors: Kenichiro
authors: K
authors: Ito
authors: Sou
authors: S
authors: Go
authors: Makoto
authors: M
authors: Komiyama
authors: Yan
authors: Y
authors: Xu
mesh_terms: D005434:Flow Cytometry; D054856:G-Quadruplexes; D005786:Gene Expression Regulation; D006367:HeLa Cells; D006801:Humans; D009690:Nucleic Acid Conformation; D012313:RNA / Q000737:chemistry*; D012333:RNA, Messenger / Q000737:chemistry* / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D012313:RNA