ISOLATION OF A LOCAL TERTIARY FOLDING TRANSITION IN THE CONTEXT OF A GLOBALLY FOLDED RNA

Citation
Gj. Narlikar et D. Herschlag, ISOLATION OF A LOCAL TERTIARY FOLDING TRANSITION IN THE CONTEXT OF A GLOBALLY FOLDED RNA, Nature structural biology, 3(8), 1996, pp. 701-710
Citations number
47
Categorie Soggetti
Biology,"Cell Biology
Journal title
ISSN journal
10728368
Volume
3
Issue
8
Year of publication
1996
Pages
701 - 710
Database
ISI
SICI code
1072-8368(1996)3:8<701:IOALTF>2.0.ZU;2-Q
Abstract
Binding of the Tetrahymena ribozyme's oligonucleotide substrate repres ents a local folding event in the context of a globally folded RNA. Su bstrate binding involves P1 duplex formation with the ribozyme's inter nal guide sequence to give an 'open complex', followed by docking of t he P1 duplex into tertiary interactions to give a 'closed complex'. We have isolated the open complex as a thermodynamically stable species using a site-specific modification and high Na+ concentrations. This h as allowed characterization of P1 docking, which represents a folding transition between local secondary and local tertiary structure. P1 do cking is entropically driven, possibly accompanied by a release of bou nd water molecules. Strategies analogous to those described here can b e used more generally to study local folding events in large structure d RNAs and to explore the structural and energetic landscape for RNA f olding.