General deoxyribozyme-catalyzed synthesis of native 3 '-5 ' RNA linkages

Department of Chemistry, University of Illinois, Urbana-Champaign, Urbana, Illinois, United States
Journal of the American Chemical Society (Impact Factor: 11.44). 10/2005; 127(38):13124-5. DOI: 10.1021/ja0533702
Source: PubMed

ABSTRACT An elusive goal for nucleic acid enzymology has been deoxyribozymes that ligate RNA rapidly, sequence-generally, with formation of native 3'-5' linkages, and in preparatively useful yield. Using in vitro selection, we have identified Mg2+- and Zn2+-dependent deoxyribozymes that simultaneously fulfill all four of these criteria. The new deoxyribozymes operate under practical incubation conditions and have modest RNA substrate sequence requirements, specifically D downward arrowRA for 9DB1 and A downward arrowR for 7DE5 (D = A, G, or U; R = A or G). These requirements are comparable to those of deoxyribozymes such as 10-23 and 8-17, which are already widely used as biochemical tools for RNA cleavage. We anticipate that the 9DB1 and 7DE5 deoxyribozymes will find immediate practical application for RNA ligation.

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