OsMSRA4.1 and OsMSRB1.1, two rice plastidial methionine sulfoxide reductases, are involved in abiotic stress responses
OsMSRA4.1 and OsMSRB1.1, two rice plastidial methionine sulfoxide reductases, are involved in abiotic stress responses
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OsMSRA4.1 和 OsMSRB1.1 是两种水稻质体甲硫氨酸亚砜还原酶，参与非生物胁迫反应
DOI：
10.1007/s00425-009-0934-2
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发表时间：
2009-06-01
期刊：
影响因子：
4.3
通讯作者：
Chu, Chengcai
中科院分区：
文献类型：
--
作者：
Guo, Xiaoli;Wu, Yaorong;Chu, Chengcai
在蛋白质中，蛋氨酸残基对氧化特别敏感，形成S-和r -蛋氨酸亚砜非对映异构体，这两种蛋氨酸亚砜可以被两种类型的蛋氨酸亚砜还原酶MSRA和MSRB特异性逆转。在此之前，我们已经从巴西旱稻（Oryza sativa L. cv.）的nacl处理根系中鉴定出一个编码MSR的基因。（Wu et al. in Plant Sci 168:847-853, 2005）。Blast数据库分析表明，水稻中至少存在4个MSRA和3个MSRB同源基因，选择其中的OsMSRA4.1和OsMSRB1.1进行功能分析。表达分析表明，OsMSRA4.1和OsMSRB1.1均在各器官中组成性表达，并可受各种应激条件诱导表达。亚细胞定位和体外活性分析表明，这两种OsMSR蛋白都能靶向叶绿体并具有MSR活性。酵母中OsMSRA4.1或OsMSRB1.1的过表达增强了细胞对氧化应激的抗性。此外，过表达osmsra4.1的转基因水稻植株在盐处理下也表现出更高的生存能力。我们的研究结果提供了osmsr参与植物胁迫反应的遗传证据。
In proteins, methionine residues are especially sensitive to oxidation, leading to the formation of S- and R-methionine sulfoxide diastereoisomers, and these two methionine sulfoxides can be specifically reversed by two types of methionine sulfoxide reductases (MSRs), MSRA and MSRB. Previously, we have identified a gene encoding a putative MSR from NaCl-treated roots of Brazilian upland rice (Oryza sativa L. cv. IAPAR 9) via subtractive suppression hybridization (Wu et al. in Plant Sci 168:847-853, 2005). Blast database analysis indicated that at least four MSRA and three MSRB orthologs exist in rice, and two of them, OsMSRA4.1 and OsMSRB1.1, were selected for further functional analysis. Expression analysis showed that both OsMSRA4.1 and OsMSRB1.1 are constitutively expressed in all organs and can be induced by various stress conditions. Subcellular localization and in vitro activity assay revealed that both OsMSR proteins are targeted to the chloroplast and have MSR activity. Overexpression of either OsMSRA4.1 or OsMSRB1.1 in yeast enhanced cellular resistance to oxidative stress. In addition, OsMSRA4.1-overexpressing transgenic rice plants also showed enhanced viability under salt treatment. Our results provide genetic evidence of the involvement of OsMSRs in the plant stress responses.