Assigning a function to a conserved group of proteins:: the tRNA 3′-processing enzymes
Assigning a function to a conserved group of proteins:: the tRNA 3′-processing enzymes
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DOI：
10.1093/emboj/21.11.2769
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发表时间：
2002-06-03
期刊：
影响因子：
11.4
通讯作者：
Marchfelder, A
中科院分区：
文献类型：
--
作者：
Schiffer, S;Rösch, S;Marchfelder, A
准确的tRNA3‘端成熟对于氨酰化是必不可少的，从而对所有生物体的蛋白质合成都是至关重要的。在这里，我们首次鉴定了tRNA3‘-加工内切酶(RNase Z)的蛋白质和DNA序列。小麦核糖核酸酶Z的纯化鉴定出与其活性相关的43 kDa蛋白。从纯化的蛋白中获得的多肽序列用于鉴定相应的基因。拟南芥和金氏甲烷球菌的同源蛋白的体外表达证实了它们的tRNA3‘-加工活性。这些RNaseZ蛋白属于ELAC1/2蛋白家族和COG1234同源蛋白簇。来自A.thaliana和M.janaschii的RNaseZ酶是这些家族中的第一个成员，现在可以将功能分配给它们。这三个王国中都存在与拟南芥和金线莲的RNase Z酶序列高度相似的蛋白质。
Accurate tRNA 3' end maturation is essential for aminoacylation and thus for protein synthesis in all organisms. Here we report the first identification of protein and DNA sequences for tRNA 3'-processing endonucleases (RNase Z). Purification of RNase Z from wheat identified a 43 kDa protein correlated with the activity. Peptide sequences obtained from the purified protein were used to identify the corresponding gene. In vitro expression of the homologous proteins from Arabidopsis thaliana and Methano coccus janaschii confirmed their tRNA 3'-processing activities. These RNase Z proteins belong to the ELAC1/2 family of proteins and to the cluster of orthologous proteins COG 1234. The RNase Z enzymes from A.thaliana and M.janaschii are the first members of these families to which a function can now be assigned. Proteins with high sequence similarity to the RNase Z enzymes from A.thaliana and M.janaschii are present in all three kingdoms.