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Influence of C-5 halogenation of uridines on hairpin versus duplex RNA folding.

ABSTRACT: Halogenation of bases is a widespread method used for solving crystal structures of nucleic acids. However, this modification may have important consequences on RNA folding and thus on the success of crystallization. We have used a combination of UV thermal melting, steady-state fluorescence, X-ray crystallography, and gel electrophoresis techniques to study the influence of uridine halogenation (bromination or iodination) on the RNA folding. The HIV-1 Dimerization Initiation Site is an RNA hairpin that can adopt an alternative duplex conformation and was used as a model. We have shown that, unexpectedly, the RNA hairpin/duplex ratio is strongly dependent not only on the presence but also on the position of halogenation.

SUBMITTER: Ennifar E

PROVIDER: S-EPMC1950758 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Influence of C-5 halogenation of uridines on hairpin versus duplex RNA folding.

Ennifar Eric E Bernacchi Serena S Wolff Philippe P Dumas Philippe P

RNA (New York, N.Y.) 20070713 9

Halogenation of bases is a widespread method used for solving crystal structures of nucleic acids. However, this modification may have important consequences on RNA folding and thus on the success of crystallization. We have used a combination of UV thermal melting, steady-state fluorescence, X-ray crystallography, and gel electrophoresis techniques to study the influence of uridine halogenation (bromination or iodination) on the RNA folding. The HIV-1 Dimerization Initiation Site is an RNA hair ...[more]

PMID: 17630326

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