Abstract This study investigated the synthesis and properties of 4′-C-guanidinomethyl-2′-O-methyluridine and RNAs containing the analog. Thermal and thermodynamic stabilities of double-stranded RNAs (dsRNAs) containing the nucleoside analog were examined. It was found that although the analog decreased the thermal and thermodynamic stabilities of dsRNA, it had base-discrimination ability. The 4′-C-guanidinomethyl modification increased stability of RNAs in a buffer containing serum. Furthermore, small interference RNAs incorporating one analog at the passenger strand still preserved their RNA interference activities. It was suggested that the 4′-guanidinomethyl modification significantly improved cell membrane permeability of RNA. Thus, 4′-C-guanidinomethyl-2′-O-methyl analogs may be useful in improving the properties of therapeutic siRNA molecules.

中文翻译：

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4'-C-胍基甲基-2'-O-甲基修饰的RNA寡聚体的合成与表征

摘要 本研究研究了 4'-C-胍基甲基-2'-O-甲基尿苷和含有该类似物的 RNA 的合成和性质。检查了含有核苷类似物的双链 RNA (dsRNA) 的热和热力学稳定性。发现虽然类似物降低了dsRNA的热稳定性和热力学稳定性，但它具有碱基区分能力。4'-C-胍基甲基修饰增加了含有血清的缓冲液中 RNA 的稳定性。此外，在过客链上掺入一种类似物的小干扰 RNA 仍保留其 RNA 干扰活性。表明 4'-胍基甲基修饰显着提高了 RNA 的细胞膜通透性。因此，