Nuclear Overhauser experiments at 500 MHz on the downfield proton spectra of 5S ribonucleic acid and its complex with ribosomal protein L25.
Nuclear Overhauser experiments at 500 MHz on the downfield proton spectra of 5S ribonucleic acid and its complex with ribosomal protein L25.
复制标题
核 Overhauser 在 500 MHz 下对 5S 核糖核酸及其与核糖体蛋白 L25 的复合物的低场质子光谱进行实验。
DOI：
10.1021/bi00280a005
复制
发表时间：
1983
期刊：
影响因子：
2.9
通讯作者：
Moore,PB
中科院分区：
文献类型：
--
作者：
Kime,MJ;Moore,PB
M. J. Kime和P. B.摩尔 * 摘要：使用核Overhauser方法在500 MHz下检查了大肠杆菌5S RNA的低场（9-15 ppm）质子谱。数据证实分子内存在末端和原核环螺旋[Fox，GE，& Woese，CR（1975）Nature（伦敦）256，505-506]。在分子的第三环中检测到非常少的稳定的双螺旋结构，所述第三环包含碱基12-68。当向系统中加入蛋白质L25时，5S RNA的低场光谱以高度特异性的方式被扰动。十多年来，核磁共振（NMR）技术一直被用来研究RNA的结构和性质[综述见Kearns & Shulman（1974）; Kearns，1976，1977; Reid & Hurd，1977; Schimmel & Red-field，1980; Reid，1981]，tRNA一直是这项工作的主题，但5S RNA，下一个更大的丰富RNA种类，也受到了关注（Wong埃塔尔，1972; Kearns & Wong，1974; Burns等人，1980; Luoma等人，1980; Salemink等人，1981年）。核酸质子的一部分，来自耶鲁大学化学系，纽黑文，康涅狄格06511。1983年1月3日接收，1983年3月4日收到修订稿。这项研究得到了美国国立卫生研究院（AI-09167）的资助（PBM）。MJK是北约/SERC博士后研究员。在由国家科学基金会（CHE-7916210）支持的东北地区NMR设施中进行NMR光谱学。表明5S RNA上L25的结合位点包括原核环螺旋，但不包括末端茎螺旋。L25和由碱基1-11、69-87和89-120组成的5S RNA片段之间形成的类似复合物显示出完全相同的光谱变化。在这些复合物的光谱中出现了许多低场共振，这些复合物在游离RNA中没有对应物，这表明蛋白质稳定了新的RNA结构。有一些迹象表明蛋白质-核酸核奥弗豪泽效应。特别感兴趣的光谱是低场区（9-15 ppm），其中氢键碱基对亚氨基质子共振。最近已经开发了基于核奥弗豪泽效应（NOE）的用于识别小核酸的低场共振的强有力的方法（约翰斯顿和雷德菲尔德，1978，1981;桑切斯等人，1980; Roy & Redfield，1981; Hare & Reid，1982 a，B; Roy等人，1982年）。很明显，在某些情况下，转移RNA光谱的归属问题将很快得到解决。
M. J. Kime and P. B. Moore* abstract: The downfield (9-15 ppm) proton spectrum of Escherichia cotí 5S RNA has been examined at 500 MHz by using nuclear Overhauser methods. The data confirm the existence of the terminal and procaryotic loop helices within the molecule [Fox, GE, & Woese, CR (1975) Nature {London) 256, 505-506]. Very little stable, double-helical structure is detectable in the third loop of the molecule, the one comprising bases 12-68. The downfield spectrum of 5S RNA is perturbed in a highly specific manner upon addition of protein L25 to the system. The changes seen strongly i^^ oton nuclear magnetic resonance (NMR) techniques have been used to study the structure and properties of RNAs for over a decade [for review see Kearns & Shulman (1974); Kearns, 1976, 1977; Reid & Hurd, 1977; Schimmel & Red-field, 1980; Reid, 1981], The tRNAs have been the subject of much of this work, but 5S RNA, the next larger abundant RNA species, has also received attention (Wong etal., 1972; Kearns & Wong, 1974; Burns et al., 1980; Luoma et al., 1980; Salemink et al., 1981). The portion of a nucleic acid proton tFrom the Department of Chemistry, Yale University, New Haven, Connecticut 06511. Received January 3, 1983·, revised manuscript received March 4, 1983. This research was supported by a grant (to PBM) from the National Institutes of Health (AI-09167). MJK is a NATO/SERC postdoctoral fellow. NMR spectroscopy was done at the Northeast Regional NMR Facility which is supported by the Na-tional Science Foundation (CHE-7916210). suggest that the binding site for L25 on 5S RNA includes the procaryotic loop helix, but not the terminal stem helix. Similar complexes formed between L25 and the 5S RNA fragment consisting of bases 1-11, 69-87, and 89-120 show exactly the same spectral alterations. A number of downfield resonances appear in the spectra of these complexes which have no counterparts in the free RNA, suggesting the stabilization of new RNA structures by the protein. There are some indications of protein-nucleicacid nuclear Overhauser effects. spectrum of particularinterest is the downfield region (9-15 ppm) where hydrogen-bonded base pair imino protons reso-nate. Powerful methodshave been developed lately for as-signing the downfield resonances of small nucleic acids based on the nuclear Overhauser effect (NOE)(Johnston & Red-field, 1978, 1981; Sanchez et al., 1980; Roy & Redfield, 1981; Hare & Reid, 1982a, b; Roy et al., 1982). It is clear that the problem of the assignment of the spectra of tRNAs will soon be solved in several cases.