title: Solution structure of an unusually stable RNA tetraplex containing G- and U-quartet structures.
abstract: A model for the solution structure of an RNA tetraplex, (rUGGGGU)4, has been obtained by two-dimensional NMR spectroscopy and molecular dynamics. The molecule is parallel stranded and Hoogsteen base-paired in 50 mM KCl, and it is so stable that three of its six imino protons have exchange half-lives measured in days at 40 degrees C. The tetraplex is stabilized by base stacking and by the hydrogen bonds in four G quartets and at least one U quartet. This is the first indication of the existence of U-quartet structures of which we are aware.
authors.affiliation: Department of Chemistry, Yale University, New Haven, Connecticut 06511.
authors.forename: C
authors.initials: C
authors.lastname: Cheong
authors.forename: P B
authors.initials: PB
authors.lastname: Moore
mesh_terms: D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D009690:Nucleic Acid Conformation; D009843:Oligoribonucleotides / Q000737:chemistry*; D012313:RNA / Q000737:chemistry / Q000648:ultrastructure; D012996:Solutions
chemical_list: D009843:Oligoribonucleotides; D012996:Solutions; D012313:RNA