The synthesis and the impact of a disulfide bridge between 2′-O-positions of two adjacent nucleotides in an RNA duplex and in the loop of RNA hairpins are reported. The incorporation of this 2′,2′-disulfide (S–S) bridge enabled thermal and enzymatic stabilization of the hairpin depending on its position in the loop. The influence of the disulfide bridge on RNA folding was studied at the HIV Dimerization Initiation Site (DIS) as an RNA sequence model. We have shown that this S–S bridge locked the hairpin form, whereas the extended duplex form was generated after the reduction of the disulfide bond in the presence of tris(2-carboxyethyl)phosphine or glutathione. Thus, the S–S bridge can be useful for understanding RNA folding; an RNA molecular beacon locked by an S–S bridge was also investigated as a sensor for the detection of glutathione.

中文翻译：

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2'，2'-二硫键桥接的二核苷酸构象锁定RNA发夹†

2'- O之间二硫键的合成及其影响报道了RNA双链体和RNA发夹环中两个相邻核苷酸的位置。这种2'，2'-二硫键（S–S）的结合可根据发夹在环中的位置实现发夹的热稳定和酶促稳定。在HIV二聚化起始位点（DIS）作为RNA序列模型研究了二硫键对RNA折叠的影响。我们已经表明，这条S–S桥锁定了发夹形式，而扩展的双链形式是在三（2-羧乙基）膦或谷胱甘肽存在下二硫键还原后生成的。因此，S–S桥对理解RNA折叠很有用。还研究了通过S–S桥锁定的RNA分子信标作为谷胱甘肽检测的传感器。