Dang Y L, Martin N C
Department of Biochemistry, University of Louisville, Kentucky 40292.
J Biol Chem. 1993 Sep 15;268(26):19791-6.
We report here the sequence of the RPM2 gene which codes for the 105-kDa protein previously purified from the mitochondria of Saccharomyces cerevisiae and shown by genetic techniques to be required for mitochondrial RNase P activity. The sequence predicts a primary translation product of 1202 residues with a molecular mass of 139 kDa and no obvious sequence similarity to any known protein in the data bases. There are 122 amino-terminal amino acids predicted by the gene that are not found in the purified protein, some of which may play a role in mitochondrial targeting of the protein. Antibodies raised against a trpE-105-kDa fusion protein recognize a 105-kDa protein in wild-type cells but not in cells carrying a disruption of the RMP2 gene. Immune, but not preimmune serum, immunoprecipitates the RNase P RNA and the mitochondrial RNase P activity. Thus, the 105-kDa protein forms a complex with RNase P RNA and is required for RNase P activity as predicted for a bona fide subunit of the enzyme.
我们在此报告RPM2基因的序列，该基因编码先前从酿酒酵母线粒体中纯化出的105 kDa蛋白质，并且通过遗传技术表明它是线粒体核糖核酸酶P（RNase P）活性所必需的。该序列预测出一个由1202个残基组成的初级翻译产物，分子量为139 kDa，并且与数据库中任何已知蛋白质均无明显的序列相似性。该基因预测有122个氨基末端氨基酸在纯化的蛋白质中未被发现，其中一些可能在该蛋白质的线粒体靶向中发挥作用。针对trpE-105 kDa融合蛋白产生的抗体可识别野生型细胞中的105 kDa蛋白质，但不能识别携带RMP2基因破坏的细胞中的该蛋白质。免疫血清而非免疫前血清可免疫沉淀RNase P RNA和线粒体RNase P活性。因此，105 kDa蛋白质与RNase P RNA形成复合物，并且如该酶的真正亚基所预测的那样，是RNase P活性所必需的。
