Protein activation of a ribozyme: the role of bacterial RNase P protein
Protein activation of a ribozyme: the role of bacterial RNase P protein
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DOI：
10.1038/sj.emboj.7600805
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发表时间：
2005-10-05
期刊：
影响因子：
11.4
通讯作者：
Pace, NR
中科院分区：
文献类型：
--
作者：
Buck, AH;Dalby, AB;Pace, NR
细菌核糖核酸酶 P (RNase P) 属于一类利用 RNA 和蛋白质来执行基本细胞功能的酶。细菌 RNase P 蛋白是体内激活细菌 RNase P RNA 所必需的，但之前的研究对其具体功能得出了相互矛盾的结论。在这里，我们使用生物化学和生物物理技术来检查大肠杆菌和枯草芽孢杆菌 RNase P 中该蛋白质的所有拟议功能。我们证明，大肠杆菌蛋白质（而不是枯草芽孢杆菌蛋白质）稳定了 RNase P RNA 的整体结构，尽管这两种蛋白质在不同程度上影响全酶二聚体形成和前体 tRNA 识别。通过将复合物中的每种蛋白质与其同源和非同源 RNA 进行比较，我们发现两种类型的全酶之间的差异主要在于 RNA，而不是各自的蛋白质成分。我们的结果调和了之前关于该蛋白质的作用的相互矛盾的结论，并支持了一个模型，即该蛋白质激活表现出多种全酶特性的局部 RNA 结构。
Bacterial ribonuclease P ( RNase P) belongs to a class of enzymes that utilize both RNAs and proteins to perform essential cellular functions. The bacterial RNase P protein is required to activate bacterial RNase P RNA in vivo, but previous studies have yielded contradictory conclusions regarding its specific functions. Here, we use biochemical and biophysical techniques to examine all of the proposed functions of the protein in both Escherichia coli and Bacillus subtilis RNase P. We demonstrate that the E. coli protein, but not the B. subtilis protein, stabilizes the global structure of RNase P RNA, although both proteins influence holoenzyme dimer formation and precursor tRNA recognition to different extents. By comparing each protein in complex with its cognate and noncognate RNA, we show that differences between the two types of holoenzymes reside primarily in the RNA and not the protein components of each. Our results reconcile previous contradictory conclusions regarding the role of the protein and support a model where the protein activates local RNA structures that manifest multiple holoenzyme properties.