Novel modes of RNA editing in mitochondria.
Novel modes of RNA editing in mitochondria.
复制标题
DOI：
10.1093/nar/gkw188
复制
发表时间：
2016-06-02
影响因子：
14.9
通讯作者：
Burger G
中科院分区：
文献类型：
--
作者：
Moreira S;Valach M;Aoulad-Aissa M;Otto C;Burger G
基因结构和表达在diplonemid线粒体是无与伦比的。基因片段化成片段（模块），分别转录，然后将模块转录物连接到连续的RNA上。注意到在模块边界处独特的尿苷插入RNA编辑的一些实例，但其他编辑类型的程度和潜在发生仍然未知。对来自乳头状双螺旋藻线粒体的深层转录组和基因组数据的比较分析揭示了10220个尿苷的转录后插入，但没有其他核苷酸的插入或缺失。此外，我们检测到总共114个取代胞嘧啶尿苷和腺苷肌苷，聚集成异常紧凑的集群。转录本中的肌苷被实验证实。这是第一次报告腺苷到肌苷编辑的mRNA和核糖体RNA在线粒体。在mRNA中，编辑主要导致氨基酸添加和非同义替换;在核糖体RNA中，它允许形成规范的二级结构。两个广泛编辑的成绩单进行了比较，在四个dipleonemid。尿苷插入编辑的模式是严格保守的，而取代编辑有显着分歧，但仍然使双酰亚胺蛋白质更类似于其他真核生物的直系同源物。我们认为，RNA编辑不仅补偿，而且维持，甚至加速，在diplonemid线粒体基因组结构和序列的超快速进化。
Gene structure and expression in diplonemid mitochondria are unparalleled. Genes are fragmented in pieces (modules) that are separately transcribed, followed by the joining of module transcripts to contiguous RNAs. Some instances of unique uridine insertion RNA editing at module boundaries were noted, but the extent and potential occurrence of other editing types remained unknown. Comparative analysis of deep transcriptome and genome data from Diplonema papillatum mitochondria reveals ∼220 post-transcriptional insertions of uridines, but no insertions of other nucleotides nor deletions. In addition, we detect in total 114 substitutions of cytosine by uridine and adenosine by inosine, amassed into unusually compact clusters. Inosines in transcripts were confirmed experimentally. This is the first report of adenosine-to-inosine editing of mRNAs and ribosomal RNAs in mitochondria. In mRNAs, editing causes mostly amino-acid additions and non-synonymous substitutions; in ribosomal RNAs, it permits formation of canonical secondary structures. Two extensively edited transcripts were compared across four diplonemids. The pattern of uridine-insertion editing is strictly conserved, whereas substitution editing has diverged dramatically, but still rendering diplonemid proteins more similar to other eukaryotic orthologs. We posit that RNA editing not only compensates but also sustains, or even accelerates, ultra-rapid evolution of genome structure and sequence in diplonemid mitochondria.