Transcription of mammalian messenger RNAs by a nuclear RNA polymerase of mitochondrial origin
Transcription of mammalian messenger RNAs by a nuclear RNA polymerase of mitochondrial origin
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DOI：
10.1038/nature03848
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发表时间：
2005-08-04
期刊：
影响因子：
64.8
通讯作者：
Chumakov, PM
中科院分区：
文献类型：
--
作者：
Kravchenko, JE;Rogozin, IB;Chumakov, PM
真核基因的转录由三种核RNA聚合酶执行，其中RNA聚合酶II被认为是唯一负责合成信使RNAs1的酶。在这里，我们证明了在人类和啮齿动物中，一些mRNAs的转录是由一种先前未知的单多肽核RNA聚合酶(spRNAP-IV)介导的。SpRNAP-IV由线粒体RNA聚合酶基因(POLRMT)的另一种转录本表达。SpRNAP-IV缺乏线粒体RNA聚合酶的262个氨基酸末端氨基酸，包括线粒体靶向信号，并定位于细胞核。SpRNAP-IV转录对RNA多聚酶II抑制剂α-Amanitin具有抗性，但对POLRMT基因特有的短干扰RNA敏感。SpRNAP-IV的启动子与RNA聚合酶II使用的启动子有很大的不同，不对转录增强子反应，包含一个共同的功能序列基序。
Transcription of eukaryotic genes is performed by three nuclear RNA polymerases, of which RNA polymerase II is thought to be solely responsible for the synthesis of messenger RNAs1. Here we show that transcription of some mRNAs in humans and rodents is mediated by a previously unknown single-polypeptide nuclear RNA polymerase (spRNAP-IV). spRNAP-IV is expressed from an alternative transcript of the mitochondrial RNA polymerase gene (POLRMT). The spRNAP-IV lacks 262 amino-terminal amino acids of mitochondrial RNA polymerase, including the mitochondrial-targeting signal, and localizes to the nucleus. Transcription by spRNAP-IV is resistant to the RNA polymease II inhibitor alpha-amanitin but is sensitive to short interfering RNA specific for the POLRMT gene. The promoters for spRNAP-IV differ substantially from those used by RNA polymerase II, do not respond to transcriptional enhancers and contain a common functional sequence motif.