The mitochondrial transcription termination factor mTERF modulates replication pausing in human mitochondrial DNA.
The mitochondrial transcription termination factor mTERF modulates replication pausing in human mitochondrial DNA.
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DOI：
10.1093/nar/gkm676
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发表时间：
2007
影响因子：
14.9
通讯作者：
Jacobs HT
中科院分区：
文献类型：
--
作者：
Hyvärinen AK;Pohjoismäki JL;Reyes A;Wanrooij S;Yasukawa T;Karhunen PJ;Spelbrink JN;Holt IJ;Jacobs HT
哺乳动物线粒体转录终止因子mTERF与tRNALeu(UUR)基因内的一个位点高亲和力结合，调节从核糖体DNA转录到线粒体DNA主要编码链(MtDNA)其余基因的读取量。凝胶迁移率改变分析(EMSA)和SELEX，使用诱导过表达mTERF的细胞线粒体蛋白提取物，发现了新的、更弱的mTERF结合位点，聚集在mtDNA的几个区域，特别是在主要的非编码区(NCR)。这种体内结合是由mtDNA免疫沉淀支持的。经双向中性琼脂糖凝胶电泳法(2DNAGE)和连接介导的聚合酶链式反应(Lm-PCR)5‘端定位，确定mTERF结合位点为复制暂停位点。停顿强度受mTERF表达水平的调节。MTERF的过表达也影响了基因组中发现mTERF结合的其他区域的复制暂停。这些结果表明，TERF除了在转录中发挥作用外，还在mtDNA复制中发挥作用。我们认为mTERF可以提供一个协调复制和转录复合体通过的系统，类似于其他系统中的复制暂停区结合蛋白，其主要作用是在促进基因组有效表达的同时保障基因组的完整性。
The mammalian mitochondrial transcription termination factor mTERF binds with high affinity to a site within the tRNALeu(UUR) gene and regulates the amount of read through transcription from the ribosomal DNA into the remaining genes of the major coding strand of mitochondrial DNA (mtDNA). Electrophoretic mobility shift assays (EMSA) and SELEX, using mitochondrial protein extracts from cells induced to overexpress mTERF, revealed novel, weaker mTERF-binding sites, clustered in several regions of mtDNA, notably in the major non-coding region (NCR). Such binding in vivo was supported by mtDNA immunoprecipitation. Two-dimensional neutral agarose gel electrophoresis (2DNAGE) and 5′ end mapping by ligation-mediated PCR (LM-PCR) identified the region of the canonical mTERF-binding site as a replication pause site. The strength of pausing was modulated by the expression level of mTERF. mTERF overexpression also affected replication pausing in other regions of the genome in which mTERF binding was found. These results indicate a role for TERF in mtDNA replication, in addition to its role in transcription. We suggest that mTERF could provide a system for coordinating the passage of replication and transcription complexes, analogous with replication pause-region binding proteins in other systems, whose main role is to safeguard the integrity of the genome whilst facilitating its efficient expression.
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影响因子：
16
作者：
Ivessa, AS;Lenzmeier, BA;Zakian, VA
通讯作者：
Zakian, VA
影响因子：
3.5
作者：
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通讯作者：
Jacobs, HT
影响因子：
14.9
作者：
Benguría, A;Hernández, P;Schvartzman, JB
通讯作者：
Schvartzman, JB
影响因子：
4.8
作者：
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通讯作者：
Bastia, D
影响因子：
5.3
作者：
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通讯作者：
CLAYTON, DA