Department of Chemistry and Biochemistry, University of Texas, Austin, TX, USA.
RNA Biol. 2010 Nov-Dec;7(6):667-76. doi: 10.4161/rna.7.6.13571. Epub 2010 Nov 1.
RNAs and RNA-protein complexes (RNPs) traverse rugged energy landscapes as they fold to their native structures, and many continue to undergo conformational rearrangements as they function. Due to the inherent stability of local RNA structure, proteins are required to assist with RNA conformational transitions during initial folding and in exchange between functional structures. DEAD-box proteins are superfamily 2 RNA helicases that are ubiquitously involved in RNA-mediated processes. Some of these proteins use an ATP-dependent cycle of conformational changes to disrupt RNA structure nonprocessively, accelerating structural transitions of RNAs and RNPs in a manner that bears a strong resemblance to the activities of certain groups of protein chaperones. This review summarizes recent work using model substrates and tractable self-splicing intron RNAs, which has given new insights into how DEAD-box proteins promote RNA folding steps and conformational transitions, and it summarizes recent progress in identifying sites and mechanisms of DEAD-box protein activity within more complex cellular targets.
RNAs 和 RNA 蛋白复合物 (RNPs) 在折叠成其天然结构时会穿越崎岖的能量景观，并且在它们发挥功能时许多复合物会继续进行构象重排。由于局部 RNA 结构的固有稳定性，在初始折叠和功能结构之间交换时，需要蛋白质来协助 RNA 构象转变。DEAD 盒蛋白是超家族 2 RNA 解旋酶，广泛参与 RNA 介导的过程。这些蛋白质中的一些利用依赖 ATP 的构象变化循环来非渐进地破坏 RNA 结构，以类似于某些蛋白质伴侣组的活性的方式加速 RNA 和 RNP 的结构转变。这篇综述总结了使用模型底物和可处理的自我剪接内含子 RNA 的最新工作，这些工作为 DEAD 盒蛋白如何促进 RNA 折叠步骤和构象转变提供了新的见解，并总结了最近在识别更复杂细胞靶标中 DEAD 盒蛋白活性的位点和机制方面的进展。
