Laboratoire de Chimie Genetique, Universite de Strasbourg and C.N.R.S., Faculte de Pharmacie, 67401 Illkirch, France.
J Am Chem Soc. 2009 Dec 16;131(49):17730-1. doi: 10.1021/ja908017e.
siRNA-mediated gene silencing requires intracellular delivery of the nucleic acid. We have developed a carrierless molecular approach that follows the same cell entry route as cationic supramolecular complexes, yet should avoid the extracellular barriers encountered by nanoparticles. Cationic oligospermine-oligonucleotide conjugates (ZNAs, for Zip Nucleic Acids) were synthesized stepwise on an oligonucleotide synthesizer using a DMT-spermine phosphoramidite derivative. They were shown to enter cells and have access to the cytoplasm, provided their formal charge ratio N/P was >1.5. Cationic siRNAs that fulfilled this condition were shown to achieve selective inhibition of luciferase gene expression in the submicromolar concentration range in constitutively luciferase-expressing cells.
siRNA 介导的基因沉默需要将核酸递送到细胞内。我们开发了一种无载体的分子方法，该方法遵循与阳离子超分子复合物相同的细胞进入途径，但应避免纳米颗粒遇到的细胞外屏障。阳离子寡聚多胺-寡核苷酸缀合物（ZNAs，用于 Zip 核酸）是在寡核苷酸合成仪上使用 DMT-多胺磷酸酰胺衍生物逐步合成的。结果表明，只要其形式电荷比 N/P 大于 1.5，它们就能够进入细胞并进入细胞质。符合此条件的阳离子 siRNA 被证明能够在组成型表达荧光素酶的细胞中以亚微摩尔浓度范围选择性抑制荧光素酶基因表达。
