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The solution structural ensembles of RNA kink-turn motifs and their protein complexes.

ABSTRACT: With the growing number of crystal structures of RNA and RNA-protein complexes, a critical next step is understanding the dynamic solution behavior of these entities in terms of conformational ensembles and energy landscapes. To this end, we have used X-ray scattering interferometry (XSI) to probe the ubiquitous RNA kink-turn motif and its complexes with the canonical kink-turn binding protein L7Ae. XSI revealed that the folded kink-turn is best described as a restricted conformational ensemble. The ions present in solution alter the nature of this ensemble, and protein binding can perturb the kink-turn ensemble without collapsing it to a unique state. This study demonstrates how XSI can reveal structural and ensemble properties of RNAs and RNA-protein complexes and uncovers the behavior of an important RNA-protein motif. This type of information will be necessary to understand, predict and engineer the behavior and function of RNAs and their protein complexes.

SUBMITTER: Shi X

PROVIDER: S-EPMC4755865 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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The solution structural ensembles of RNA kink-turn motifs and their protein complexes.

Shi Xuesong X Huang Lin L Lilley David M J DM Harbury Pehr B PB Herschlag Daniel D

Nature chemical biology 20160104 3

With the growing number of crystal structures of RNA and RNA-protein complexes, a critical next step is understanding the dynamic solution behavior of these entities in terms of conformational ensembles and energy landscapes. To this end, we have used X-ray scattering interferometry (XSI) to probe the ubiquitous RNA kink-turn motif and its complexes with the canonical kink-turn binding protein L7Ae. XSI revealed that the folded kink-turn is best described as a restricted conformational ensemble. ...[more]

PMID: 26727239

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