Crystal structure of a bulged RNA tetraplex at 1.1 Å resolution:: Implications for a novel binding site in RNA tetraplex
Crystal structure of a bulged RNA tetraplex at 1.1 Å resolution:: Implications for a novel binding site in RNA tetraplex
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DOI：
10.1016/j.str.2003.09.017
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发表时间：
2003-11-01
期刊：
影响因子：
5.7
通讯作者：
Sundaralingam, M
中科院分区：
文献类型：
--
作者：
Pan, BC;Xiong, Y;Sundaralingam, M
凸起是RNA中一个重要的结构基序，在RNA-蛋白质相互作用和RNA-RNA相互作用中可以作为识别和相互作用的位点。在这里，我们报道了1.1埃分辨率的膨胀的RNA四链的第一个晶体结构。六聚体r(U)(BR)DG)r(UGGU)形成一个平行的四链，尿苷被鸟嘌呤夹在中间凸出。膨胀的尿苷采用糖苷构象，其O2和N3原子面向外，是有效的识别和相互作用部位。凸起的形成既加宽了沟槽宽度，又改变了沟槽5‘侧的氢键模式。然而，凸起不会在四链结构中造成任何弯曲或扭曲。本研究证明了尿苷和鸟嘌呤在形成四链结构方面的显著差异。此外，还观察到G(Syn)四分体和G(ANT)四分体。它们在凹槽中表现出相同的碱基配对模式和相似的C1‘-C1’距离，但不同的氢键模式。
Bulges are an important structural motif in RNA and can be used as recognition and interaction sites in RNA-protein interaction and RNA-RNA interaction. Here we report the first crystal structure of a bulged RNA tetraplex at 1.1 Angstrom resolution. The hexamer r(U)(Br)dG) r(UGGU) forms a parallel tetraplex with the uridine sandwiched by guanines bulging out. The bulged uridine adopts the syn glycosidic conformation and its O2 and N3 atoms face outwards, serving as an effective recognition and interaction site. The bulge formation both widens the groove width and changes the groove hydrogen-bonding pattern on its 5' side. However, the bulge does not make any bends or kinks in the tetraplex structure. The present study demonstrates the dramatic difference between uridine and guanine in forming tetraplex structure. In addition, both G(syn) tetrad and G(antt) tetrad have been observed. They display the same base-pairing pattern and similar C1'-C1' distance but different hydrogen-bonding patterns in the groove.