Sochacka E, Czerwinska G, Guenther R, Cain R, Agris P F, Malkiewicz A
Institute of Organic Chemistry, Technical University of Lódz, Poland.
Nucleosides Nucleotides Nucleic Acids. 2000 Mar;19(3):515-31. doi: 10.1080/15257770008035004.
The phosphoramidites of 6-methyluridine and 5,6-dimethyluridine were synthesized and the modified uridines site-selectively incorporated into heptadecamers corresponding in sequence to the yeast tRNA(Phe) anticodon and TpsiC domains. The oligoribonucleotides were characterized by NMR, MALDI-TOF MS and UV-monitored thermal denaturations. The 6-methylated uridines retained the syn conformation at the polymer level and in each sequence location destabilized the RNAs compared to that of the unmodified RNA. The decrease in RNA duplex stability is predictable. However, loss of stability when the modified uridine is in a loop is sequence context dependent, and can not, at this time, be predicted from the location in the loop.
合成了6-甲基尿苷和5,6-二甲基尿苷的亚磷酰胺，并将修饰的尿苷位点选择性地掺入到与酵母tRNA(Phe)反密码子和TpsiC结构域序列对应的十七聚体中。通过核磁共振、基质辅助激光解吸电离飞行时间质谱和紫外监测热变性对寡核糖核苷酸进行了表征。6-甲基化的尿苷在聚合物水平上保持了顺式构象，并且在每个序列位置上，与未修饰的RNA相比，使RNA不稳定。RNA双链稳定性的降低是可预测的。然而，当修饰的尿苷处于环中时稳定性的丧失取决于序列上下文，目前无法从环中的位置进行预测。
