Laboratory of Plant Molecular Genetics, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Gene. 2010 Apr 1;454(1-2):39-46. doi: 10.1016/j.gene.2010.01.008. Epub 2010 Feb 1.
C-to-U RNA editing (i.e., alteration of a C in the genomic sequence to U in the transcript) has been confirmed widely in angiosperm organellar genomes. During the C-to-U RNA editing event, incomplete edited transcripts have been observed at many sites in the steady-state mRNA population (partial editing). Here, by using coexpression analysis and the surveillance of whole editing status on the mitochondrial genome, we have revealed that a pentatricopeptide repeat (PPR) protein classified into the P subfamily (PPR596) has site-specific influence on the efficiency of C-to-U RNA editing events at partial editing sites on the Arabidopsis thaliana mitochondrial genome. Previous works have revealed that PPR proteins classified into the PLS subfamily containing the E or E and DYW motif are involved in RNA editing as trans-factors; they are believed to recruit deaminase at editing sites. In contrast with the mutant analyses of PLS-subfamily PPR proteins, the editing efficiency at rps3eU1344SS was revealed to be significantly increased in ppr596 mutants. Our study implies P-subfamily PPR protein is involved in the control of the degree of partial editing.
C 到 U 的 RNA 编辑（即将基因组序列中的 C 改变为转录本中的 U）已在被子植物细胞器基因组中得到广泛证实。在 C 到 U 的 RNA 编辑事件中，在稳定态 mRNA 群体中的许多位点观察到不完全编辑的转录本（部分编辑）。在这里，我们通过共表达分析和对线粒体基因组的整体编辑状态的监测，揭示了一种五肽重复（PPR）蛋白被分类为 P 亚家族（PPR596），对拟南芥线粒体基因组部分编辑位点的 C 到 U 的 RNA 编辑事件的效率具有特定的影响。先前的工作表明，被分类为含有 E 或 E 和 DYW 基序的 PLS 亚家族的 PPR 蛋白作为转因子参与 RNA 编辑；它们被认为可以在编辑位点募集脱氨酶。与 PLS 亚家族 PPR 蛋白的突变分析相反，在 ppr596 突变体中，rps3eU1344SS 的编辑效率显著增加。我们的研究表明，P 亚家族 PPR 蛋白参与控制部分编辑的程度。
