Zhang Li, Yao Lei, Zhang Ning, Yang Jiangwei, Zhu Xi, Tang Xun, Calderón-Urrea Alejandro, Si Huaijun
Gansu Provincial Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Genetic and Germplasm Enhancement, Gansu Agricultural University, Lanzhou, China.
College of Life Science and Technology, Gansu Agricultural University, Lanzhou, China.
Front Plant Sci. 2018 Mar 29;9:383. doi: 10.3389/fpls.2018.00383. eCollection 2018.
The NAC designation is derived from petunia () gene () and genes and (), which belongs to the family of plant-specific transcription factors (TFs), and plays important role in plant development processes, such as response to biotic and abiotic stress, and hormone signaling. MicroRNAs (miRNAs) are a class of small, non-coding endogenous RNAs which play versatile and significant role in plant stress response and development via negatively affecting gene expression at a post-transcriptional level. Here, we showed that Stu-mi164 had a complementary sequence in the CDS sequence of potato NAC TFs, and that NAC expression exhibited significant differences under osmotic stress. We measured expression levels of the Stu-mi164 target gene between control and PEG-treated plants using real-time PCR, and the results demonstrated that they had inverse relationship. We suggested that Stu-miR164 might drive overexpression of gene under osmotic stress in potato. To confirm the regulation of NAC TFs by Stu-mi164, we developed transgenic plants, using -mediated transformation, of the potato cultivars "Gannongshu 2" and "Kexin 3" overexpressing the Stu-mi164 or the TF . Real-time PCR analysis of transgenic potato plants under osmotic (PEG) stress, showed that potato plants overexpressing Stu-mi164 had reduced expression of and their osmotic resistance decreased. Furthermore, these plants had low number of lateral roots although the same length as the control. Our findings support the regulatory role of Stu-miRNAs in controlling plant response to osmotic stress via .
NAC命名源自矮牵牛（）基因（）以及基因和（），它属于植物特异性转录因子（TFs）家族，在植物发育过程中发挥重要作用，如对生物和非生物胁迫的响应以及激素信号传导。微小RNA（miRNAs）是一类小的非编码内源性RNA，通过在转录后水平上负向影响基因表达，在植物胁迫响应和发育中发挥多种重要作用。在此，我们表明Stu-mi164在马铃薯NAC转录因子的CDS序列中有互补序列，并且NAC表达在渗透胁迫下表现出显著差异。我们使用实时PCR测量了对照植物和PEG处理植物之间Stu-mi164靶基因的表达水平，结果表明它们呈负相关。我们推测Stu-miR164可能在马铃薯渗透胁迫下驱动基因的过表达。为了证实Stu-mi164对NAC转录因子的调控作用，我们利用介导的转化方法培育了过表达Stu-mi164或转录因子的马铃薯品种“甘农薯2号”和“克新3号”的转基因植物。对渗透（PEG）胁迫下的转基因马铃薯植株进行实时PCR分析表明，过表达Stu-mi164的马铃薯植株的表达降低，其抗渗性下降。此外，这些植株的侧根数量较少，尽管长度与对照相同。我们的研究结果支持了Stu-miRNAs通过调控植物对渗透胁迫的响应。
