Functional and Applied Genomics Laboratory, National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi, 110067, India.
Planta. 2013 Nov;238(5):871-84. doi: 10.1007/s00425-013-1940-y. Epub 2013 Aug 6.
Glutaredoxins (GRXs) are the ubiquitous oxidoreductase enzymes, which play an important role in defense against various stresses. Here, we report the role of a CC-type GRX gene from rice, OsGRX8, in abiotic stress tolerance. OsGRX8 protein was found to be localized in nucleus and cytosol and its gene expression is induced by various stress conditions and plant hormone auxin. The over-expression of OsGRX8 in Arabidopsis plants conferred reduced sensitivity to auxin and stress hormone, abscisic acid. In addition, the transgenic Arabidopsis plants exhibited enhanced tolerance to various abiotic stresses, including salinity, osmotic and oxidative stress. Further, the transgenic RNAi rice plants exhibited increased susceptibility to various abiotic stresses, which further confirmed the role of OsGRX8 in abiotic stress responses. The microarray data analysis revealed that expression of a large number of auxin-responsive, known stress-associated and transcription factor encoding genes was altered in GRX transgenic Arabidopsis plants in response to exogenous auxin and stress conditions as compared to wild-type plants. Altogether, these findings suggest the role of OsGRX8 in regulating abiotic stress response and may be used to engineer stress tolerance in crop plants.
谷氧还蛋白（GRXs）是普遍存在的氧化还原酶，在抵御各种胁迫方面发挥着重要作用。在这里，我们报告了一种来自水稻的 CC 型 GRX 基因 OsGRX8 在非生物胁迫耐受性中的作用。发现 OsGRX8 蛋白定位于细胞核和细胞质中，其基因表达受各种胁迫条件和植物激素生长素的诱导。在拟南芥植物中过表达 OsGRX8 赋予了对生长素和应激激素脱落酸的敏感性降低。此外，转基因拟南芥植物表现出对各种非生物胁迫的耐受性增强，包括盐胁迫、渗透胁迫和氧化胁迫。此外，转基因 RNAi 水稻植物对各种非生物胁迫的敏感性增加，这进一步证实了 OsGRX8 在非生物胁迫反应中的作用。微阵列数据分析显示，与野生型植物相比，GRX 转基因拟南芥植物中外源生长素和应激条件下大量生长素应答、已知应激相关和转录因子编码基因的表达发生改变。总之，这些发现表明 OsGRX8 在调节非生物胁迫反应中的作用，并可用于工程作物的胁迫耐受性。
