title: Tertiary structure around the guanosine-binding site of the Tetrahymena ribozyme.
abstract: A cleavage reagent directed to the active site of the Tetrahymena catalytic RNA was synthesized by derivatization of the guanosine substrate with a metal chelator. When complexed with iron(II), this reagent cleaved the RNA in five regions. Cleavage at adenosine 207, which is far from the guanosine-binding site in the primary and secondary structure, provides a constraint for the higher order folding of the RNA. This cleavage site constitutes physical evidence for a key feature of the Michel-Westhof model. Targeting a reactive entity to a specific site should be generally useful for determining proximity within folded RNA molecules or ribonucleoprotein complexes.
authors.affiliation: Howard Hughes Medical Institute, Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309-0215.
authors.forename: J F
authors.initials: JF
authors.lastname: Wang
authors.forename: T R
authors.initials: TR
authors.lastname: Cech
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D004492:Edetic Acid / Q000378:metabolism; D005609:Free Radicals; D006151:Guanosine / Q000378:metabolism*; D006157:Guanosine Monophosphate / Q000378:metabolism; D007501:Iron / Q000378:metabolism; D007502:Iron Chelating Agents / Q000378:metabolism; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D004369:Pentetic Acid / Q000378:metabolism; D016337:RNA, Catalytic / Q000737:chemistry* / Q000378:metabolism; D013768:Tetrahymena / Q000737:chemistry*
chemical_list: D005609:Free Radicals; D007502:Iron Chelating Agents; D016337:RNA, Catalytic; D006151:Guanosine; D004369:Pentetic Acid; D006157:Guanosine Monophosphate; D004492:Edetic Acid; D007501:Iron