Perbandt M, Nolte A, Lorenz S, Bald R, Betzel C, Erdmann V A
Institut für Biochemie, Freie Universität Berlin, Germany.
FEBS Lett. 1998 Jun 12;429(2):211-5. doi: 10.1016/s0014-5793(98)00436-0.
The synthetic RNA fragment 5'-CUGGGCGG(GCGA)CCGCCUGG (nucleotides in parentheses indicate the loop region) corresponds to the natural sequence of domain E from nucleotides 79-97 of the Thermus flavus 5S rRNA including a hairpin loop. The RNA structure determined at 3.0 A and refined to an R-value of 24.1% also represents the first X-ray structure GNRA tetraloop. The loop is in distinctly different conformation from other GNRA tetraloops analyzed by NMR. The conformation of the two molecules in the asymmetric unit is influenced and stabilized by specific intermolecular contacts. The structural features presented here give evidence for the ability of RNA molecules to adapt to specific environments.
合成的RNA片段5'-CUGGGCGG(GCGA)CCGCCUGG（括号中的核苷酸表示环区）对应于嗜热栖热菌5S rRNA中E结构域79至97位核苷酸的天然序列，包括一个发夹环。在3.0埃分辨率下测定并精修至R值为24.1%的RNA结构也代表了首个X射线晶体结构的GNRA四环。该环与通过核磁共振分析的其他GNRA四环具有明显不同的构象。不对称单元中两个分子的构象受到特定分子间相互作用的影响并得以稳定。此处呈现的结构特征证明了RNA分子适应特定环境的能力。
