RNA PROCESSING FACTOR 5 is required for efficient 5 cleavage at a processing site conserved in RNAs of three different mitochondrial genes in Arabidopsis thaliana
RNA PROCESSING FACTOR 5 is required for efficient 5 cleavage at a processing site conserved in RNAs of three different mitochondrial genes in Arabidopsis thaliana
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DOI：
10.1111/tpj.12143
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发表时间：
2013-05-01
期刊：
影响因子：
7.2
通讯作者：
Binder, Stefan
中科院分区：
文献类型：
--
作者：
Hauler, Aron;Jonietz, Christian;Binder, Stefan
许多线粒体转录物的5端是转录后产生的。最近，我们在拟南芥中鉴定了3个不同线粒体mRNA末端成熟所需的RNA加工因子。所有这些因子都是五肽重复蛋白（PPRPs），与育性恢复因子（RF）高度相似，可挽救不同物种细胞质雄性不育系的雄性育性。因此，我们提出了这些RF样PPRP在线粒体5加工中的一般作用。我们现在鉴定了RNA加工因子5，一种未归类为RF样蛋白的PPRP，它是nad6和atp9 mRNA以及26S rRNA有效成熟所必需的。这些RNA的前体分子共享保守的序列元件，相对于成熟的5mRNA末端大约在50至+9位的范围内，表明这些序列是加工所需的顺式元件的至少一部分。RPF 5的敲除对atp9 mRNA的5个加工只有中等影响，而成熟的nad 6 mRNA和26S rRNA的产生在突变体中几乎完全被废除。后者导致总26S rRNA种类减少50%，导致大rRNA和18S rRNA之间的不平衡。尽管这些严重的变化，RNA水平和26S和18S rRNA之间的比例，线粒体蛋白水平似乎是不变的突变体，而种子发芽能力显着降低。
The 5 ends of many mitochondrial transcripts are generated post-transcriptionally. Recently, we identified three RNA PROCESSING FACTORs required for 5 end maturation of different mitochondrial mRNAs in Arabidopsis thaliana. All of these factors are pentatricopeptide repeat proteins (PPRPs), highly similar to RESTORERs OF FERTILTY (RF), that rescue male fertility in cytoplasmic male-sterile lines from different species. Therefore, we suggested a general role of these RF-like PPRPs in mitochondrial 5 processing. We now identified RNA PROCESSING FACTOR 5, a PPRP not classified as an RF-like protein, required for the efficient 5 maturation of the nad6 and atp9 mRNAs as well as 26S rRNA. The precursor molecules of these RNAs share conserved sequence elements, approximately ranging from positions 50 to +9 relative to mature 5 mRNA termini, suggesting these sequences to be at least part of the cis elements required for processing. The knockout of RPF5 has only a moderate influence on 5 processing of atp9 mRNA, whereas the generation of the mature nad6 mRNA and 26S rRNA is almost completely abolished in the mutant. The latter leads to a 50% decrease of total 26S rRNA species, resulting in an imbalance between the large rRNA and 18S rRNA. Despite these severe changes in RNA levels and in the proportion between the 26S and 18S rRNAs, mitochondrial protein levels appear to be unaltered in the mutant, whereas seed germination capacity is markedly reduced.