The PPR protein encoded by the LOVASTATIN INSENSITIVE 1 gene is involved in RNA editing at three sites in mitochondria of Arabidopsis thaliana
The PPR protein encoded by the LOVASTATIN INSENSITIVE 1 gene is involved in RNA editing at three sites in mitochondria of Arabidopsis thaliana
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DOI：
10.1111/j.1365-313x.2009.04076.x
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发表时间：
2010-02-01
期刊：
影响因子：
7.2
通讯作者：
Takenaka, Mizuki
中科院分区：
文献类型：
--
作者：
Verbitskiy, Daniil;Zehrmann, Anja;Takenaka, Mizuki
开花植物线粒体中的转录后 RNA 编辑将数百个核苷酸从胞苷改变为尿苷，其中大部分是在 mRNA 中。为了表征植物线粒体中 RNA 编辑所涉及的因素，我们启动了对特定位点 RNA 编辑缺陷的核突变体的筛选。在这里，我们鉴定了核编码基因 MEF11，该基因参与拟南芥中 cox3-422、nad4-124 和 ccb203-344 三个位点的 RNA 编辑。该基因的 T-DNA 插入系先前被表征为显示出对化合物洛伐他汀（类异戊二烯生物合成甲羟戊酸途径的抑制剂）增强的耐受性。这里描述的 mef11-1 突变体对洛伐他汀表现出相似的耐受性。 MEF11 蛋白在位点特异性线粒体 RNA 编辑中的功能的鉴定表明，从线粒体到细胞质的逆行信号传导具有间接影响，从而引起甲羟戊酸途径的改变。编辑位点 cox3-422 和 ccb203-344 各自改变各自蛋白质中保守的氨基酸，而 nad4-124 位点则保持沉默。 mef11-1 突变体中的单个氨基酸变化发生在第二个五肽重复序列中，表明该基序是位点特异性 RNA 编辑所必需的。
Post-transcriptional RNA editing in flowering plant mitochondria alters several hundred nucleotides from cytidine to uridine, mostly in mRNAs. To characterize the factors involved in RNA editing in plant mitochondria, we initiated a screen for nuclear mutants defective in RNA editing at specific sites. Here we identify the nuclear-encoded gene MEF11, which is involved in RNA editing of the three sites cox3-422, nad4-124 and ccb203-344 in Arabidopsis thaliana. A T-DNA insertion line of this gene was previously characterized as showing enhanced tolerance to the compound lovastatin, an inhibitor of the mevalonate pathway of isoprenoid biosynthesis. The mef11-1 mutant described here shows similar tolerance to lovastatin. Identification of the function of the MEF11 protein in site-specific mitochondrial RNA editing suggests indirect effects of retrograde signalling from mitochondria to the cytoplasm to evoke alteration of the mevalonate pathway. The editing sites cox3-422 and ccb203-344 each alter amino acids that are conserved in the respective proteins, while the nad4-124 site is silent. The single amino acid change in the mef11-1 mutant occurs in the second pentatricopeptide repeat, suggesting that this motif is required for site-specific RNA editing.