QUANTITATIVE STRUCTURAL-ANALYSIS OF EUKARYOTIC RIBOSOMAL-RNA BY SCANNING-TRANSMISSION ELECTRON-MICROSCOPY
QUANTITATIVE STRUCTURAL-ANALYSIS OF EUKARYOTIC RIBOSOMAL-RNA BY SCANNING-TRANSMISSION ELECTRON-MICROSCOPY
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DOI：
10.1073/pnas.82.17.5598
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发表时间：
1985-01-01
影响因子：
11.1
通讯作者：
BOUBLIK, M
中科院分区：
文献类型：
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作者：
OOSTERGETEL, GT;WALL, JS;BOUBLIK, M
从幼仓鼠肾细胞中分离的28 S核糖体RNA的构象进行了研究，通过扫描透射电子显微镜（STEM）和圆二色性光谱建立的条件下，未染色的冻干rRNA的STEM图像是一个有意义的代表性的溶液中的rRNA的构象。我们已经确定了在各种缓冲条件下的28 S rRNA的构象，分子质量，质量分布，和单个分子内的多核苷酸链的数量，和表观回转半径。28 S rRNA分子在水中高度延伸，并随着离子强度的增加而变得紧密。然而，即使在“重构缓冲液”（30 mM Tris/HCl/20 mM MgCl 2/360 mM KCl，pH 7.6）中，致密性也没有达到rRNA分子在结构上与60 S核糖体亚基相似的状态。我们的方法在核酸和核酸-蛋白质相互作用的高分辨率结构研究中具有广泛的应用。
The conformation of 28S ribosomal RNA isolated from baby hamster kidney cells was studied by scanning transmission electron microscopy (STEM) and circular dichroic spectroscopy to establish the conditions under which STEM images of unstained freeze-dried rRNA are a meaningful representation of the conformation of rRNA in solution. We have determined the conformation of 28S rRNA under various buffer conditions, the molecular mass, the mass distribution, and the number of polynucleotide strands within the individual molecules, and the apparent radii of gyration. The 28S rRNA molecule is highly extended in water and becomes compact with increasing ionic strength. However, even in the "reconstitution buffer" (30 mM Tris/HCl/20 mM MgCl2/360 mM KCl, pH 7.6) the compactness does not reach a state in which the rRNA molecule appears structurally similar to the 60S ribosomal subunit. Our approach has a broad application in high-resolution structural studies of nucleic acids and nucleic acid-protein interactions.