title: A nanostructure made of a bacterial noncoding RNA.
abstract: Natural RNAs, unlike many proteins, have never been reported to form extended nanostructures, despite their wide variety of cellular functions. This is all the more striking, as synthetic DNA and RNA forming large nanostructures have long been successfully designed. Here, we show that DsrA, a 87-nt noncoding RNA of Escherichia coli, self-assembles into a hierarchy of nanostructures through antisense interactions of three contiguous self-complementary regions. Yet, the extended nanostructures, observed using atomic force microscopy (AFM) and fluorescence microscopy, are easily disrupted into >100 nm long helical bundles of DsrA filaments, including hundreds of DsrA monomers, and are surprisingly resistant to heat and urea denaturation. Molecular modeling demonstrates that this structural switch of DsrA nanostructures into filament bundles results from the relaxation of stored torsional constraints and suggests possible implications for DsrA regulatory function.
authors.affiliation: Institut Curie, Research Division, CNRS UMR 168, Paris 75248, France.
authors.forename: Bastien
authors.initials: B
authors.lastname: Cayrol
authors.forename: Claude
authors.initials: C
authors.lastname: Nogues
authors.forename: Alexandre
authors.initials: A
authors.lastname: Dawid
authors.forename: Irit
authors.initials: I
authors.lastname: Sagi
authors.forename: Pascal
authors.initials: P
authors.lastname: Silberzan
authors.forename: Hervé
authors.initials: H
authors.lastname: Isambert
mesh_terms: D001483:Base Sequence; D018625:Microscopy, Atomic Force; D008969:Molecular Sequence Data; D049329:Nanostructures; D009690:Nucleic Acid Conformation; D012329:RNA, Bacterial / Q000737:chemistry*; D022661:RNA, Untranslated / Q000737:chemistry*
chemical_list: D012329:RNA, Bacterial; D022661:RNA, Untranslated