Jiang Yanjuan, Qiu Yuping, Hu Yanru, Yu Diqiu
Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences Kunming, China.
National Plateau Wetlands Research Center, Southwest Forestry University Kunming, China.
Front Plant Sci. 2016 Feb 11;7:145. doi: 10.3389/fpls.2016.00145. eCollection 2016.
Drought stress is a severe environmental factor that greatly restricts plant distribution and crop production. Recently, we have found that overexpressing AtWRKY57 enhanced drought tolerance in Arabidopsis thaliana. In this study, we further reported that the Arabidopsis WRKY57 transcription factor was able to confer drought tolerance to transgenic rice (Oryza sativa) plants. The enhanced drought tolerance of transgenic rice was resulted from the lower water loss rates, cell death, malondialdehyde contents and relative electrolyte leakage while a higher proline content and reactive oxygen species-scavenging enzyme activities was observed during stress conditions. Moreover, further investigation revealed that the expression levels of several stress-responsive genes were up-regulated in drought-tolerant transgenic rice plants, compared with those in wild-type plants. In addition to the drought tolerance, the AtWRKY57 over-expressing plants also had enhanced salt and PEG stress tolerances. Taken together, our study indicates that over-expressing AtWRKY57 in rice improved not only drought tolerance but also salt and PEG tolerance, demonstrating its potential role in crop improvement.
干旱胁迫是一种严重的环境因素，极大地限制了植物的分布和作物产量。最近，我们发现过表达AtWRKY57可增强拟南芥的耐旱性。在本研究中，我们进一步报道，拟南芥WRKY57转录因子能够赋予转基因水稻植株耐旱性。转基因水稻耐旱性增强的原因是水分流失率、细胞死亡、丙二醛含量和相对电解质渗漏较低，而在胁迫条件下脯氨酸含量较高且活性氧清除酶活性较高。此外，进一步研究表明，与野生型植株相比，耐旱转基因水稻植株中几个胁迫响应基因的表达水平上调。除了耐旱性外，过表达AtWRKY57的植株还具有增强的耐盐性和耐PEG胁迫性。综上所述，我们的研究表明，在水稻中过表达AtWRKY57不仅提高了耐旱性，还提高了耐盐性和耐PEG胁迫性，证明了其在作物改良中的潜在作用。
