Two interacting PPR proteins are major Arabidopsis editing factors in plastid and mitochondria
Two interacting PPR proteins are major Arabidopsis editing factors in plastid and mitochondria
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DOI：
10.1073/pnas.1705780114
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发表时间：
2017-08-15
影响因子：
11.1
通讯作者：
Lurin, Claire
中科院分区：
文献类型：
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作者：
Guillaumot, Damien;Lopez-Obando, Mauricio;Lurin, Claire
RNA编辑是在陆地植物细胞器基因表达过程中将数百种胞嘧啶转化为尿氨酸。五肽重复(PPR)蛋白是这种转录后RNA修饰的核心。即使PPR蛋白定义了编辑位点，相同或另一种PPR蛋白的dyw结构域也被认为催化了脱氨基作用。为了深入了解细胞器RNA编辑体，我们对质膜叶绿体生物发生19(CLB19)PPR编辑因子进行了串联亲和纯化。两个针对线粒体和叶绿体的PPR蛋白被确定为CLB19的潜在合作伙伴。这两种蛋白质，一种P型PPR和一个小的PPR-Dyw亚家族的成员，被证明在酵母中相互作用。插入突变导致胚胎致死，这可以通过胚胎特异性互补来挽救。对这些互补植物的转录组分析表明，这两个细胞器都存在主要的编辑缺陷，具有很高的PPR类型特异性，表明这两个蛋白是E+型PPR编辑小体的核心成员。
RNA editing is converting hundreds of cytosines into uridines during organelle gene expression of land plants. The pentatricopeptide repeat (PPR) proteins are at the core of this posttranscriptional RNA modification. Even if a PPR protein defines the editing site, a DYW domain of the same or another PPR protein is believed to catalyze the deamination. To give insight into the organelle RNA editosome, we performed tandem affinity purification of the plastidial CHLOROPLAST BIOGENESIS 19 (CLB19) PPR editing factor. Two PPR proteins, dually targeted to mitochondria and chloroplasts, were identified as potential partners of CLB19. These two proteins, a P-type PPR and a member of a small PPR-DYW subfamily, were shown to interact in yeast. Insertional mutations resulted in embryo lethality that could be rescued by embryo-specific complementation. A transcriptome analysis of these complemented plants showed major editing defects in both organelles with a very high PPR type specificity, indicating that the two proteins are core members of E+-type PPR editosomes.