T. C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD, USA.
RNA Biol. 2010 Nov-Dec;7(6):677-86. doi: 10.4161/rna.7.6.13615. Epub 2010 Nov 1.
Many non-coding RNAs fold into complex three-dimensional structures, yet the self-assembly of RNA structure is hampered by mispairing, weak tertiary interactions, electrostatic barriers, and the frequent requirement that the 5' and 3' ends of the transcript interact. This rugged free energy landscape for RNA folding means that some RNA molecules in a population rapidly form their native structure, while many others become kinetically trapped in misfolded conformations. Transient binding of RNA chaperone proteins destabilize misfolded intermediates and lower the transition states between conformations, producing a smoother landscape that increases the rate of folding and the probability that a molecule will find the native structure. DEAD-box proteins couple the chemical potential of ATP hydrolysis with repetitive cycles of RNA binding and release, expanding the range of conditions under which they can refold RNA structures.
许多非编码 RNA 折叠成复杂的三维结构，但 RNA 结构的自组装受到错配、弱三级相互作用、静电障碍以及转录本的 5' 和 3' 末端相互作用的频繁要求的阻碍。RNA 折叠的这种崎岖不平的自由能景观意味着群体中的一些 RNA 分子迅速形成其天然结构，而许多其他 RNA 分子在动力学上被困在错误折叠的构象中。RNA 分子伴侣蛋白的瞬时结合使错误折叠的中间体失稳，并降低构象之间的转变状态，产生更平滑的景观，从而提高折叠速度和分子找到天然结构的概率。DEAD 盒蛋白将 ATP 水解的化学势与 RNA 结合和释放的重复循环偶联起来，扩大了它们能够重折叠 RNA 结构的条件范围。
