Persistence length changes dramatically as RNA folds.

G Caliskan; C Hyeon; U Perez-Salas; R M Briber; S A Woodson; D Thirumalai

doi:10.1103/physrevlett.95.268303

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Persistence length changes dramatically as RNA folds.

G Caliskan·C Hyeon·U Perez-Salas·R M Briber·S A Woodson·D Thirumalai

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Abstract

We determine the persistence length l(p) for a bacterial group I ribozyme as a function of concentration of monovalent and divalent cations by fitting the distance distribution functions P(r) obtained from small angle x-ray scattering intensity data to the asymptotic form of the calculated P(WLC)(r) for a wormlike chain. The l(p) values change dramatically over a narrow range of Mg(2+) concentration from approximately 21 Angstroms in the unfolded state (U) to approximately 10 Angstroms in the compact (I(C)) and native states. Variations in l(p) with increasing Na(+) concentration are more gradual. In accord with the predictions of polyelectrolyte theory we find l(p) alpha 1/kappa(2) where kappa is the inverse Debye-screening length.

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Computer Simulation Models, Chemical Models, Molecular Nucleic Acid Conformation RNA, Bacterial RNA, Catalytic Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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G Caliskan, C Hyeon, U Perez-Salas, R M Briber, S A Woodson, D Thirumalai. 2005-12-29. Persistence length changes dramatically as RNA folds.. https://doi.org/10.1103/physrevlett.95.268303

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