RNA editing in kinetoplastid mitochondria.
RNA editing in kinetoplastid mitochondria.
复制标题
动质体线粒体中的 RNA 编辑。
DOI：
10.1096/fasebj.7.1.8422975
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Pollard,VW
中科院分区：
文献类型：
--
作者：
Hajduk,SL;Harris,ME;Pollard,VW
动质体原生动物线粒体中的RNA编辑导致mrna中尿苷残基的转录后添加和删除。mrna的编辑可以导致线粒体翻译起始密码子的形成，在RNA水平上纠正框架移位的基因，并且在广泛编辑的mrna中，形成完整的阅读框。着丝质体RNA编辑需要来自两个或多个单独转录基因的遗传信息汇集在一起，形成成熟的、编辑过的mRNA。在mRNA中正确插入或删除尿苷所需的信息存在于称为引导rna （gRNAs）的小线粒体转录本中。mrna的编辑似乎与一种称为编辑体的高分子量复合物有关，该复合物含有特定的grna、未编辑的mrna和蛋白质。编辑可能是一个两步的过程，首先是在编辑位点破坏磷酸二酯键，然后形成一个嵌合分子，gRNA共价连接到mRNA的3 ‘部分的5 ’端。嵌合体是通过将mRNA的5 ‘端重新连接到mRNA的3 ’部分，并在连接点添加或删除尿苷来解决的。对RNA编辑的生化机制提出了两种模型。第一个是酶促级联的切割和连接，而另一个支持连续的转酯反应。编辑着丝质体线粒体的明显功能需要是可翻译mrna的形成。编辑的进化起源和编辑在调节线粒体基因表达中的作用远不太清楚。- Hajduk， S. L, Harris， M. E, Pollard， V. W.着丝质体线粒体中的RNA编辑。中华医学杂志[j] .7: 54‐63；1993.
RNA editing in the mitochondrion of kinetoplastid protozoa results in the posttranscriptional addition and deletion of uridine residues in mRNAs. Editing of mRNAs can lead to the formation of initiation codons for mitochondrial translation, the correction of frame‐shifted genes at the RNA level, and in extensively edited mRNAs, the formation of complete reading frames. Kinetoplastid RNA editing requires that genetic information from two or more separately transcribed genes be brought together to form the mature, edited mRNA. The information necessary for the proper insertion or deletion of uridines in the mRNA is present in small mitochondrial transcripts termed guide RNAs (gRNAs). Editing of mRNAs appears to be associated with a high molecular weight complex, called the editosome, containing specific gRNAs, unedited mRNAs, and proteins. Editing is likely a two‐step process involving first the breakage of a phosphodiester bond at the editing site and formation of a chimeric molecule with a gRNA covalently joined to the 5′ end of the 3′ portion of an mRNA. The chimera is resolved by the rejoining of the 5′ end of the mRNA to the 3′ portion of the mRNA with the addition or deletion of a uridine at the junction point. Two models are proposed for the biochemical mechanism of RNA editing. The first is an enzymatic cascade of cleavage and ligation while the other supports successive rounds of transesterification. The obvious functional necessity for editing in kinetoplastid mitochondria is the formation of translatable mRNAs. Far less clear is the evolutionary origin of editing and the role editing plays in regulating mitochondrial gene expression.— Hajduk, S. L., Harris, M. E., and Pollard, V. W. RNA editing in kinetoplastid mitochondria.FASEB J.7: 54‐63; 1993.