Shi Xuesong, Huang Lin, Lilley David M J, Harbury Pehr B, Herschlag Daniel
Department of Biochemistry, Stanford University, Stanford, California, USA.
Nucleic Acid Structure Research Group, School of Life Sciences, University of Dundee, Dundee, UK.
Nat Chem Biol. 2016 Mar;12(3):146-52. doi: 10.1038/nchembio.1997. Epub 2016 Jan 4.
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.
随着RNA及RNA-蛋白质复合物晶体结构数量的不断增加，关键的下一步是从构象集合和能量景观的角度理解这些实体的动态溶液行为。为此，我们使用X射线散射干涉术（XSI）来探测普遍存在的RNA扭结转角基序及其与典型扭结转角结合蛋白L7Ae的复合物。XSI表明，折叠后的扭结转角最好描述为一个受限的构象集合。溶液中存在的离子改变了这个集合的性质，蛋白质结合可以扰动扭结转角集合而不会使其坍缩到一个独特的状态。这项研究展示了XSI如何揭示RNA和RNA-蛋白质复合物的结构和集合性质，并揭示了一个重要的RNA-蛋白质基序的行为。这类信息对于理解、预测和设计RNA及其蛋白质复合物的行为和功能是必要的。
