Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A 0B8, Canada.
Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
Nucleic Acids Res. 2018 Feb 28;46(4):1614-1623. doi: 10.1093/nar/gky024.
We report, herein, a new class of RNAi trigger molecules based on the unconventional parallel hybridization of two oligonucleotide chains. We have prepared and studied several parallel stranded (ps) duplexes, in which the parallel orientation is achieved through incorporation of isoguanine and isocytosine to form reverse Watson-Crick base pairs in ps-DNA:DNA, ps-DNA:RNA, ps-(DNA-2'F-ANA):RNA, and ps-DNA:2'F-RNA duplexes. The formation of these duplexes was confirmed by UV melting experiments, FRET and CD studies. In addition, NMR structural studies were conducted on a ps-DNA:RNA hybrid for the first time. Finally, we provide evidence for the unprecedented finding that ps-DNA:RNA and ps-DNA:2'F-RNA hybrids can engage the RNAi pathway to silence gene expression in vitro.
我们在此报告了一类新的 RNAi 触发分子，它们基于两条寡核苷酸链的非常规平行杂交。我们已经制备并研究了几种平行链（ps）双链体，其中平行取向是通过掺入异鸟嘌呤和异胞嘧啶在 ps-DNA:DNA、ps-DNA:RNA、ps-(DNA-2'F-ANA):RNA 和 ps-DNA:2'F-RNA 双链体中形成反向 Watson-Crick 碱基对来实现的。通过 UV 熔融实验、FRET 和 CD 研究证实了这些双链体的形成。此外，首次对 ps-DNA:RNA 杂交体进行了 NMR 结构研究。最后，我们提供了证据，证明了前所未有的发现，即 ps-DNA:RNA 和 ps-DNA:2'F-RNA 杂交体可以通过 RNAi 途径在体外沉默基因表达。
