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Real-time multidimensional NMR follows RNA folding with second resolution.

ABSTRACT: Conformational transitions and structural rearrangements are central to the function of many RNAs yet remain poorly understood. We have used ultrafast multidimensional NMR techniques to monitor the adenine-induced folding of an adenine-sensing riboswitch in real time, with nucleotide-resolved resolution. By following changes in 2D spectra at rates of approximately 0.5 Hz, we identify distinct steps associated with the ligand-induced folding of the riboswitch. Following recognition of the ligand, long range loop-loop interactions form and are then progressively stabilized before the formation of a fully stable complex over approximately 2-3 minutes. The application of these ultrafast multidimensional NMR methods provides the opportunity to determine the structure of RNA folding intermediates and conformational trajectories.

SUBMITTER: Lee MK

PROVIDER: S-EPMC2889053 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Real-time multidimensional NMR follows RNA folding with second resolution.

Lee Mi-Kyung MK Gal Maayan M Frydman Lucio L Varani Gabriele G

Proceedings of the National Academy of Sciences of the United States of America 20100503 20

Conformational transitions and structural rearrangements are central to the function of many RNAs yet remain poorly understood. We have used ultrafast multidimensional NMR techniques to monitor the adenine-induced folding of an adenine-sensing riboswitch in real time, with nucleotide-resolved resolution. By following changes in 2D spectra at rates of approximately 0.5 Hz, we identify distinct steps associated with the ligand-induced folding of the riboswitch. Following recognition of the ligand, ...[more]

PMID: 20439766

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