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Rapid compaction during RNA folding.

ABSTRACT: We have used small angle x-ray scattering and computer simulations with a coarse-grained model to provide a time-resolved picture of the global folding process of the Tetrahymena group I RNA over a time window of more than five orders of magnitude. A substantial phase of compaction is observed on the low millisecond timescale, and the overall compaction and global shape changes are largely complete within one second, earlier than any known tertiary contacts are formed. This finding indicates that the RNA forms a nonspecifically collapsed intermediate and then searches for its tertiary contacts within a highly restricted subset of conformational space. The collapsed intermediate early in folding of this RNA is grossly akin to molten globule intermediates in protein folding.

SUBMITTER: Russell R

PROVIDER: S-EPMC123637 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature

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Rapid compaction during RNA folding.

Russell Rick R Millett Ian S IS Tate Mark W MW Kwok Lisa W LW Nakatani Bradley B Gruner Sol M SM Mochrie Simon G J SG Pande Vijay V Doniach Sebastian S Herschlag Daniel D Pollack Lois L

Proceedings of the National Academy of Sciences of the United States of America 20020401 7

We have used small angle x-ray scattering and computer simulations with a coarse-grained model to provide a time-resolved picture of the global folding process of the Tetrahymena group I RNA over a time window of more than five orders of magnitude. A substantial phase of compaction is observed on the low millisecond timescale, and the overall compaction and global shape changes are largely complete within one second, earlier than any known tertiary contacts are formed. This finding indicates tha ...[more]

PMID: 11929997

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