Abstract
We previously used in vitro selection to identify the 7S11 deoxyribozyme, which catalyzes formation of 2′,5′-branched RNA using a branch-site adenosine nucleophile and a 5′-triphosphate electrophile. An unanswered question is whether the use of branch-site adenosine is inherently preferred or a chance event during the particular selection experiment. Here we have found that deoxyribozymes newly selected to use uridine as the branch-site RNA nucleotide in a structural context that resembles natural RNA splicing instead prefer a branch-site adenosine, although adenosine was never available during the selection itself. Our results support a chemical basis for nature's choice of the branch-site nucleotide, which is almost always adenosine in group II introns and the spliceosome.
Original language | English (US) |
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Pages (from-to) | 2767-2771 |
Number of pages | 5 |
Journal | Biochemistry |
Volume | 45 |
Issue number | 9 |
DOIs | |
State | Published - Mar 7 2006 |
ASJC Scopus subject areas
- Biochemistry