College of Life Sciences, Liaoning Normal University, Key Laboratory of Plant Biotechnology of Liaoning Province, Dalian 116081, PR China.
Gene. 2014 Jun 15;543(2):190-7. doi: 10.1016/j.gene.2014.04.025. Epub 2014 Apr 16.
The plant-specific NAC (NAM, ATAF1/2, and CUC) transcription factors have diverse roles in plant development and stress responses. In this study, a stress-responsive NAC gene, SlNAC2, was isolated and characterized from high-throughput Solexa sequencing of Suaeda liaotungensis. SlNAC2 showed high similarity to other NACs, especially ATAF subgroup members. Transcripts of SlNAC2 appeared in many Suaeda tissues including leaves, stems and roots. In particular, SlNAC2 was strongly expressed in leaves. Expression analysis showed that SlNAC2 was highly induced during salt and low temperature stress in leaves. Subcellular localization showed that the SlNAC2 protein localized to the nucleus. A transactivation assay in yeast demonstrated that SlNAC2 activated the expression of a reporter gene. To test its function, SlNAC2 was transformed into Arabidopsis under the control of the CaMV-35S promoter. Functional analysis showed that its overexpression resulted in enhanced tolerance to salinity stress. Therefore, SlNAC2 is a multifunctional regulatory factor in plants, and might be a good candidate gene for genetic improvement to produce stress tolerant plants.
植物特异性 NAC（NAM、ATAF1/2 和 CUC）转录因子在植物发育和应激反应中具有多种作用。本研究从高通量 Solexa 测序的辽东碱蓬中分离和鉴定了一个应激响应 NAC 基因 SlNAC2。SlNAC2 与其他 NAC 基因具有高度相似性，特别是 ATAF 亚组成员。SlNAC2 的转录本出现在许多辽东碱蓬组织中，包括叶片、茎和根。特别是，SlNAC2 在叶片中强烈表达。表达分析表明，SlNAC2 在叶片中对盐和低温胁迫高度诱导。亚细胞定位表明 SlNAC2 蛋白定位于细胞核。酵母中转激活测定表明 SlNAC2 激活报告基因的表达。为了测试其功能，SlNAC2 在 CaMV-35S 启动子的控制下被转化为拟南芥。功能分析表明，其过表达导致对盐胁迫的耐受性增强。因此，SlNAC2 是植物中一种多功能调节因子，可能是遗传改良产生耐胁迫植物的候选基因。
