RNAs can mimic the information storage, replication and catalysis functions of DNAs and proteins, providing physical evidence for the widely accepted RNA world hypothesis that RNA alone constitutes earlier life forms. However, the currently found molecular chaperones for correcting RNA folding are proteins, which poses a question on whether RNA itself can avoid misfolding in the absence of proteins. Here, we report two examples that RNA/ssDNA strands can serve as molecular chaperones to assist the folding of RNA/ssDNA structures with complex intramolecular interactions. We found that these RNA chaperones can disrupt the misfolded double-hairpin structures, assisting them to refold into native single-hairpin structures, which is a typical catalytical assembly called catassembly. The refolding rate was increased by at least three orders of magnitude. The identification that RNA can function as molecular chaperone for RNA folding may expand our understanding on RNA molecular chaperone and provides clues to rational design of catassembler.

RNA可以模拟DNA和蛋白质的信息存储，复制和催化功能，从而为广泛接受的RNA世界假说提供物理证据，该假说仅由RNA构成较早的生命形式。然而，目前发现的用于校正RNA折叠的分子伴侣是蛋白质，这提出了一个问题，即RNA本身是否可以避免在缺乏蛋白质的情况下发生错误折叠。在这里，我们报告两个例子，RNA / ssDNA链可以充当分子伴侣，以协助RNA / ssDNA结构的折叠与复杂的分子内相互作用。我们发现这些RNA分子伴侣可以破坏错折叠的双发夹结构，帮助它们重新折叠成天然的单发夹结构，这是一种典型的催化装配，称为catassembly。重折叠速度至少增加了三个数量级。