title: Specificity for 3',5'-linked substrates in RNA-catalyzed RNA polymerization.
abstract: The finding that ribozymes can catalyze RNA chain elongation has led to the proposal that an early self-replicating system could have consisted of RNA alone. In such a chain elongation reaction, the Tetrahymena ribozyme was found to select 3',5'-linked substrates from a pool that contained a large molar excess of 2',5'-linked dinucleotides. The enzyme neither reacted with nor was inhibited by 2',5' phosphodiester linkages. The ability to exclude incorrectly linked substrates would have conferred an important selective advantage to a primordial RNA molecule with RNA replicase activity.
authors: Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309-0347.
authors: B
authors: B
authors: Young
authors: T R
authors: TR
authors: Cech
mesh_terms: D000818:Animals; D012313:RNA / Q000378:metabolism*; D012322:RNA Precursors / Q000378:metabolism; D016337:RNA, Catalytic; D012335:RNA, Ribosomal / Q000378:metabolism*; D012324:RNA-Dependent RNA Polymerase / Q000378:metabolism; D012641:Selection, Genetic; D013379:Substrate Specificity; D013768:Tetrahymena / Q000201:enzymology / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D012322:RNA Precursors; D016337:RNA, Catalytic; D012335:RNA, Ribosomal; D012313:RNA; D012324:RNA-Dependent RNA Polymerase