Examination of the Dimerization States of the Single-stranded RNA Recognition Protein Pentatricopeptide Repeat 10 (PPR10)
Examination of the Dimerization States of the Single-stranded RNA Recognition Protein Pentatricopeptide Repeat 10 (PPR10)
复制标题
检查单链 RNA 识别蛋白五肽重复序列 10 (PPR10) 的二聚化状态。
DOI：
10.1074/jbc.m114.575472
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发表时间：
2014-11-07
影响因子：
4.8
通讯作者：
Yan, Nieng
中科院分区：
文献类型：
--
作者：
Li, Quanxiu;Yan, Chuangye;Yan, Nieng
五肽重复序列（PPR）蛋白，特别是丰富的质体和线粒体的被子植物，包括大量的序列特异性RNA结合蛋白，参与细胞器RNA代谢的各个方面。PPR蛋白含有多个串联重复序列，并且每个重复序列可以以模块化方式通过残基2、5和35特异性地识别RNA碱基。玉米叶绿体中PPR10的晶体结构在18个核苷酸的psaJ RNA元件存在和不存在的情况下都表现出二聚体的存在。然而，以前的生化分析表明，单体移动的PPR10 RNA结合。在这份报告中，我们表明，PPR10的氨基末端部分决定PPR10的二聚化状态。在PPR10的重复10内半胱氨酸至丝氨酸的单个氨基酸改变进一步驱动PPR10的二聚化。PPR 10二聚化的决定因素的生物化学阐明可能提供一个重要的基础，以了解PPR蛋白的工作机制，其背后的各种生理功能。
Pentatricopeptide repeat (PPR) proteins, particularly abundant in plastids and mitochrondria of angiosperms, include a large number of sequence-specific RNA binding proteins that are involved in diverse aspects of organelle RNA metabolisms. PPR proteins contain multiple tandom repeats, and each repeat can specifically recognize a RNA base through residues 2, 5, and 35 in a modular fashion. The crystal structure of PPR10 from maize chloroplast exhibits dimeric existence both in the absence and presence of the 18-nucleotide psaJ RNA element. However, previous biochemical analysis suggested a monomeric shift of PPR10 upon RNA binding. In this report, we show that the amino-terminal segments of PPR10 determine the dimerization state of PPR10. A single amino acid alteration of cysteine to serine within repeat 10 of PPR10 further drives dimerization of PPR10. The biochemical elucidation of the determinants for PPR10 dimerization may provide an important foundation to understand the working mechanisms of PPR proteins underlying their diverse physiological functions.