Ivanov Sergei, Alekseev Yakov, Bertrand Jean-Remi, Malvy Claude, Gottikh Marina B
Belozersky Institute of Physico-Chemical Biology and Department of Chemistry, Moscow State University, Moscow 119899, Russia.
Nucleic Acids Res. 2003 Jul 15;31(14):4256-63. doi: 10.1093/nar/gkg443.
Hybridization properties of oligodeoxyxylonucleotides (OXNs) built from pyrimidine monomers with an inverted 3'-OH group of the furanose have been studied using the gel mobility shift, UV melting and circular dichroism (CD) spectroscopy methods. Pyrimidine OXNs form triple helices with complementary purine RNA in which one OXN is parallel and another is antiparallel with respect to the RNA target. Surprisingly, no duplex formation between the pyrimidine OXNs and purine RNAs is detected. The modified triplexes are stable at pH 7. Their thermal stability depends on the number of C(G-C) triplets and, for G-rich RNA sequences, it is comparable with the stability of native DNA-RNA duplexes. The CD spectra of triplexes formed by OXNs with purine RNA targets are similar to spectra of A-type helices. A pyrimidine OXN having a clamp structure efficiently inhibits reverse transcription of murine pim-1 mRNA in vitro mediated by the Mo-MuLV reverse transcriptase.
利用凝胶迁移率变动分析、紫外熔解和圆二色光谱法研究了由具有呋喃糖3'-OH基团倒置的嘧啶单体构建的寡聚脱氧木糖核苷酸（OXN）的杂交特性。嘧啶OXN与互补嘌呤RNA形成三链螺旋，其中一个OXN相对于RNA靶标是平行的，另一个是反平行的。令人惊讶的是，未检测到嘧啶OXN与嘌呤RNA之间形成双链体。修饰的三链体在pH 7时稳定。它们的热稳定性取决于C（G-C）三联体的数量，对于富含G的RNA序列，其与天然DNA-RNA双链体的稳定性相当。由OXN与嘌呤RNA靶标形成的三链体的圆二色光谱类似于A型螺旋的光谱。具有钳夹结构的嘧啶OXN在体外能有效抑制莫洛尼鼠白血病病毒（Mo-MuLV）逆转录酶介导的小鼠pim-1 mRNA的逆转录。
