Nucleotides in 16S rRNA protected by the association of 30 S and 50 S ribosomal subunits
Nucleotides in 16S rRNA protected by the association of 30 S and 50 S ribosomal subunits
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DOI：
10.1006/jmbi.1998.2242
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发表时间：
1999-01-08
影响因子：
5.6
通讯作者：
Noller, HF
中科院分区：
文献类型：
--
作者：
Merryman, C;Moazed, D;Noller, HF
我们已经研究了30 S亚基与50 S亚基的16 S rRNA的相互作用，使用一系列化学探针，监测RNA碱基和骨架的可及性。所述探针包括1-环己基-3-甲基-2-（三氟甲基）苯甲酸酯。（2 -吗啉乙基）碳二亚胺甲基对甲苯磺酸盐（CMCT;探测N-3处的U和N-1处的G），焦碳酸二乙酯（DEPC;至N-7处的探针A），硫酸二甲酯（DMS;在N-1处探测A，在N-3处探测C），（以探测N-1和N-2处的G）、由游离Fe（II）-EDTA产生的羟基自由基（以探测骨架核糖基团）和Pb（II）。通过探针RNA的引物延伸鉴定反应位点。这些亚基的结合保护了16 S rRNA的11个核苷酸的碱基和90多个核苷酸的核糖基团。受碱基特异性探针保护的核苷酸通常彼此相邻，并被糖-磷酸骨架保护所包围;因此，用不同探针获得的结果相互证实。大多数受保护的核苷酸存在于位置250、700、790、900和1408-1495周围的五个延伸茎环结构中。这些区域位于亚基的平台和底部，在重建的电子显微照片中可见的亚基间桥的一般附近。我们的研究结果提供了一个广泛的地图的核苷酸在16 S rRNA可能参与亚基-亚基相互作用。(C)北京：科学出版社.
We have studied the interaction of 16 S rRNA in 30 S subunits with 50 S subunits using a series of chemical probes that monitor the accessibility of the RNA bases and backbone. The probes include 1-cyclohexyl-3-(2 -morpholinoethyl) carbodiimide metho-p-toluene sulfonate (CMCT; to probe U at N-3 and G at N-1), diethylpyrocarbonate (DEPC; to probe A at N-7), dimethyl sulfate (DMS; to probe A at N-1, and C at N-3), kethoxal (to probe G at N-1 and N-2), hydroxyl radicals generated by free Fe(II)-EDTA (to probe the backbone ribose groups) and Pb(II). The sites of reaction were identified by primer extension of the probed RNA. Association of the subunits protects the bases of 11 nucleotides and the ribose groups of over 90 nucleotides of 16 S rRNA. The nucleotides protected from the base-specific probes are often adjacent to one another and surrounded by sugar-phosphate backbone protections; thus, the results obtained with the different probes confirmed each other. Most of the protected nucleotides occur in five extended-stem-loop structures around positions 250, 700, 790, 900, and 1408-1495. These regions are located in the platform and bottom of the subunit in the general vicinity of inter-subunit bridges that are visible in reconstructed electron micrographs. Our results provide an extensive map of the nucleotides in 16 S rRNA that are likely to be involved in subunit-subunit interactions. (C) 1999 Academic Press.