title: RNA tertiary structure mediation by adenosine platforms.
abstract: The crystal structure of a group I intron domain reveals an unexpected motif that mediates both intra- and intermolecular interactions. At three separate locations in the 160-nucleotide domain, adjacent adenosines in the sequence lie side-by-side and form a pseudo-base pair within a helix. This adenosine platform opens the minor groove for base stacking or base pairing with nucleotides from a noncontiguous RNA strand. The platform motif has a distinctive chemical modification signature that may enable its detection in other structured RNAs. The ability of this motif to facilitate higher order folding provides one explanation for the abundance of adenosine residues in internal loops of many RNAs.
authors.affiliation: Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Cate
authors.forename: A R
authors.initials: AR
authors.lastname: Gooding
authors.forename: E
authors.initials: E
authors.lastname: Podell
authors.forename: K
authors.initials: K
authors.lastname: Zhou
authors.forename: B L
authors.initials: BL
authors.lastname: Golden
authors.forename: A A
authors.initials: AA
authors.lastname: Szewczak
authors.forename: C E
authors.initials: CE
authors.lastname: Kundrot
authors.forename: T R
authors.initials: TR
authors.lastname: Cech
authors.forename: J A
authors.initials: JA
authors.lastname: Doudna
mesh_terms: D000241:Adenosine / Q000737:chemistry*; D000818:Animals; D001482:Base Composition; D006860:Hydrogen Bonding; D007438:Introns; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D016337:RNA, Catalytic / Q000737:chemistry*; D016053:RNA, Protozoan / Q000737:chemistry*; D016808:Tetrahymena thermophila / Q000235:genetics
chemical_list: D016337:RNA, Catalytic; D016053:RNA, Protozoan; D000241:Adenosine