Department of Genetics, Darmstadt University of Technology, Germany.
Annu Rev Microbiol. 2012;66:65-82. doi: 10.1146/annurev-micro-092611-150150.
RNA editing describes a chemically diverse set of biomolecular reactions in which the nucleotide sequence of RNA molecules is altered. Editing reactions have been identified in many organisms and frequently contribute to the maturation of organellar transcripts. A special editing reaction has evolved within the mitochondria of the kinetoplastid protozoa. The process is characterized by the insertion and deletion of uridine nucleotides into otherwise nontranslatable messenger RNAs. Kinetoplastid RNA editing involves an exclusive class of small, noncoding RNAs known as guide RNAs. Furthermore, a unique molecular machinery, the editosome, catalyzes the process. Editosomes are megadalton multienzyme assemblies that provide a catalytic surface for the individual steps of the reaction cycle. Here I review the current mechanistic understanding and molecular inventory of kinetoplastid RNA editing and the editosome machinery. Special emphasis is placed on the molecular morphology of the editing complex in order to correlate structural features with functional characteristics.
RNA 编辑描述了一系列化学多样性的生物分子反应，其中 RNA 分子的核苷酸序列发生了改变。编辑反应已在许多生物中被鉴定出来，并且经常有助于细胞器转录物的成熟。一种特殊的编辑反应在动基体原生动物的线粒体中进化而来。该过程的特征是将尿嘧啶核苷酸插入到原本不可翻译的信使 RNA 中。动基体 RNA 编辑涉及一类独特的小非编码 RNA，称为指导 RNA。此外，一种独特的分子机制，即编辑体，催化了这一过程。编辑体是兆道尔顿的多酶复合物，为反应循环的各个步骤提供了催化表面。在这里，我回顾了动基体 RNA 编辑和编辑体机制的当前机制理解和分子清单。特别强调编辑复合物的分子形态，以便将结构特征与功能特征相关联。
