Sponsor
This project was supported by a research grant from the National Aeronautics and Space Administration (NNG04-GM20G) to N.L. Funding to pay the Open Access publication charges for this article was provided by NASA
Published In
Nucleic Acids Research
Document Type
Article
Publication Date
11-29-2007
Subjects
Catalytic RNA, Oligonucleotides -- Synthesis, RNA-protein interactions
Abstract
RNA oligomers of length 40–60 nt can self-assemble into covalent versions of the Azoarcus group I intron ribozyme. This process requires a series of recombination reactions in which the internal guide sequence of a nascent catalytic complex makes specific interactions with a complement triplet, CAU, in the oligomers. However, if the CAU were mutated, promiscuous self-assembly may be possible, lessening the dependence on a particular set of oligomer sequences. Here, we assayed whether oligomers containing mutations in the CAU triplet could still self-construct Azoarcus ribozymes. The mutations CAC, CAG, CUU and GAU all inhibited self-assembly to some degree, but did not block it completely in 100mM MgCl₂. Oligomers containing the CAC mutation retained the most self-assembly activity, while those containing GAU retained the least, indicating that mutations more 5’ in this triplet are the most deleterious. Self-assembly systems containing additional mutant locations were progressively less functional. Analyses of properly self-assembled ribozymes revealed that, of two recombination mechanisms possible for selfassembly, termed ‘tF2’ and ‘R2F2’, the simpler one-step ‘tF2’ mechanism is utilized when mutations exist. These data suggest that self-assembling systems are more facile than previously believed, and have relevance to the origin of complex ribozymes during the RNA World.
DOI
10.1093/nar/gkm1055
Persistent Identifier
http://archives.pdx.edu/ds/psu/8405
Citation Details
Draper, W.E.; Hayden, E.J.; Lehman, N. (2008). Mechanisms of covalent self-assembly of the Azoarcus ribozyme from four fragment oligonucleotides. Nucleic Acids Research 36:520-531.
Description
Copyright 2007 The Author(s) This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Article originally appeared in Nucleic Acids Research, published by Oxford University Press, and can be found at http://dx.doi.org/10.1093/nar/gkm1055