Division of Chemistry, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
Sci Rep. 2017 Jul 27;7(1):6695. doi: 10.1038/s41598-017-07050-w.
In this study, by combining nuclear magnetic resonance (NMR), circular dichroism (CD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and gel electrophoresis, we report an unusual topological structure of the RNA G-quadruplex motif formed by human telomere RNA r(UAGGGU) containing 8-bromoguanosine. Results showed that the RNA sequence formed an antiparallel tetramolecular G-quadruplex, in which each pair of diagonal strands run in opposite directions. Furthermore, guanosines were observed both in syn- and anti-conformations. In addition, two of these G-quadruplex subunits were found to be stacking on top of each other, forming a dimeric RNA G-quadruplex. Our findings provide a new insight into the behavior of RNA G-quadruplex structures.
在这项研究中，我们通过结合核磁共振（NMR）、圆二色性（CD）、液相色谱-电喷雾电离-质谱（LC-ESI-MS）和凝胶电泳，报告了一种由人端粒 RNA r（UAGGGU）形成的含有 8-溴鸟嘌呤核苷的 RNA G-四链体基序的异常拓扑结构。结果表明，该 RNA 序列形成了反平行四聚体 G-四链体，其中每对对角链朝相反方向运行。此外，观察到鸟嘌呤处于顺式和反式构象。此外，发现其中两个 G-四链体亚基彼此堆叠，形成二聚体 RNA G-四链体。我们的发现为 RNA G-四链体结构的行为提供了新的见解。
