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Structural properties and gene-silencing activity of chemically modified DNA-RNA hybrids with parallel orientation.

ABSTRACT: 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.

SUBMITTER: Habibian M

PROVIDER: S-EPMC5829573 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Structural properties and gene-silencing activity of chemically modified DNA-RNA hybrids with parallel orientation.

Habibian Maryam M Yahyaee-Anzahaee Maryam M Lucic Matije M Moroz Elena E Martín-Pintado Nerea N Di Giovanni Logan Dante LD Leroux Jean-Christophe JC Hall Jonathan J González Carlos C Damha Masad J MJ

Nucleic acids research 20180201 4

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, FR ...[more]

PMID: 29373740

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