Cheong H K, Cheong C, Lee Y S, Seong B L, Choi B S
Magnetic Resonance Group, Korea Basic Science Institute, Eoun-dong 52, Yusung-gu, Taejon 305-333, Korea.
Nucleic Acids Res. 1999 Mar 1;27(5):1392-7. doi: 10.1093/nar/27.5.1392.
The structure of a 34 nucleotide RNA molecule in solution, which contains the conserved panhandle sequences, was determined by NMR spectroscopy and molecular modeling. The partially double-strandedpanhandle structure of the influenza virus RNA serves to regulate initiation and termination of viral transcription as well as polyadenylation. The panhandle RNA consists of internal loop flanked by short helices. The nucleotides at or near the internal loop are crucial for polymerase binding and transcriptional activity. They show more flexible conformational character than the Watson-Crick base-paired region, especially for the backbone torsion angles of alpha, gamma and delta. Although residues A10 and A12 are stacked in the helix, the phosphodiester backbones are distorted. Residues A12, A13 and G25 show dynamic sugar conformations and the backbone conformations of these nucleotides are flexible. This backbone conformation and its associated flexibility may be important for protein-RNA interactions as well as base-specific interactions.
通过核磁共振光谱法和分子建模确定了溶液中一个含有保守锅柄序列的34个核苷酸的RNA分子的结构。流感病毒RNA的部分双链锅柄结构用于调节病毒转录的起始和终止以及聚腺苷酸化。锅柄RNA由内部环和两侧的短螺旋组成。内部环处或附近的核苷酸对于聚合酶结合和转录活性至关重要。它们表现出比沃森-克里克碱基配对区域更灵活的构象特征，特别是对于α、γ和δ的主链扭转角。尽管A10和A12残基堆积在螺旋中，但磷酸二酯主链发生了扭曲。A12、A13和G25残基表现出动态的糖构象，这些核苷酸的主链构象是灵活的。这种主链构象及其相关的灵活性对于蛋白质-RNA相互作用以及碱基特异性相互作用可能很重要。
