The Pentratricopeptide Repeat Protein Pigment-Defective Mutant2 is Involved in the Regulation of Chloroplast Development and Chloroplast Gene Expression in Arabidopsis
The Pentratricopeptide Repeat Protein Pigment-Defective Mutant2 is Involved in the Regulation of Chloroplast Development and Chloroplast Gene Expression in Arabidopsis
复制标题
五肽重复蛋白色素缺陷突变体2参与拟南芥叶绿体发育和叶绿体基因表达的调节。
DOI：
10.1093/pcp/pcx004
复制
发表时间：
2017-04-01
影响因子：
4.9
通讯作者：
Xiao, Jianwei
中科院分区：
文献类型：
--
作者：
Du, Liang;Zhang, Jian;Xiao, Jianwei
功能叶绿体的发育是植物自养生长发育所必需的，它由一系列核编码的辅助蛋白因子辅助。为了了解叶绿体发育的分子机制，我们分离并鉴定了一个色素缺陷突变体pdm2及其相应的杂色RNA干扰(RNAi)系。序列分析表明，PDM2编码一个属于P亚群的五肽重复蛋白。共聚焦显微镜分析和免疫印迹分析表明，PDM2定位于基质中。在RNAi植物中，与蛋白质相关的光合作用严重受损。此外，对叶绿体基因转录谱的分析表明，在RNAi植物中，叶绿体编码的聚合酶依赖的转录水平显著降低，而核编码的聚合酶依赖的转录水平上升。此外，PDM2通过直接与多个细胞器RNA编辑因子2(MORF2)和MORF9相互作用，影响大多数编辑位点的质体RNA编辑效率。因此，我们的结果表明，PDM2可能参与了叶绿体正常发育所需的叶绿体基因表达的调节。
The development of functional chloroplasts, which is assisted by a series of nuclear-encoded auxiliary protein factors, is essential for plant autotrophic growth and development. To understand the molecular mechanisms underlying chloroplast development, we isolated and characterized a pigment-defective mutant, pdm2, and its corresponding variegated RNA interference (RNAi) lines in Arabidopsis. Sequence analysis revealed that PDM2 encodes a pentatricopeptide repeat protein that belongs to the P subgroup. Confocal microscopic analysis and immunoblotting of the chloroplast protein fraction showed that PDM2 was located in the stroma. In RNAi plants, protein-related photosynthesis was severely compromised. Furthermore, analysis of the transcript profile of chloroplast genes revealed that plastid-encoded polymerase-dependent transcript levels were markedly reduced, while nuclear-encoded polymerase-dependent transcript levels were increased, in RNAi plants. In addition, PDM2 affects plastid RNA editing efficiency in most editing sites, apparently by directly interacting with multiple organellar RNA editing factor 2 (MORF2) and MORF9. Thus, our results demonstrate that PDM2 is probably involved in the regulation of plastid gene expression required for normal chloroplast development.