Biotechnology Research Institute of Chinese Academy of Agricultural Sciences, No. 12 Zhong Guan Cun South Street, Beijing 100081, China.
Gene. 2013 Jun 1;521(2):265-73. doi: 10.1016/j.gene.2013.03.068. Epub 2013 Mar 29.
NAC transcription factors are plant-specific and play an important role in responses to biotic and abiotic stresses. Populus euphratica is a salt-tolerant tree species growing in semi-arid saline areas. A stress responsive gene was successfully isolated from this species and named PeNAC1. The isolated cDNA encoded a protein containing a conserved NAC domain that belonged to the ATAF subgroup of the NAC protein family. The protein was localized to the nucleus and its C-terminus had transcriptional activation activity. Northern hybridization showed that its expression was strongly induced by drought and salt stress, but only slightly induced by ABA treatment in P. euphratica. Transgenic Arabidopsis overexpressing PeNAC1 showed enhanced tolerance to salt stress, with lower Na(+)/K(+) ratios in the roots and leaves, and significantly inhibited expression levels of AtHKT1. Our results suggest that PeNAC1 plays a role in the plant response to salt stress by regulating Na(+)/K(+) homeostasis.
NAC 转录因子是植物特有的，在生物和非生物胁迫响应中发挥重要作用。胡杨是一种生长在半干旱盐渍地区的耐盐树种。本研究从该物种中成功分离出一个胁迫响应基因，并将其命名为 PeNAC1。该分离的 cDNA 编码的蛋白含有一个保守的 NAC 结构域，属于 NAC 蛋白家族的 ATAF 亚组。该蛋白定位于细胞核，其 C 端具有转录激活活性。Northern 杂交显示，其表达受干旱和盐胁迫强烈诱导，但在 P. euphratica 中仅受 ABA 处理轻微诱导。过表达 PeNAC1 的转基因拟南芥对盐胁迫表现出增强的耐受性，根和叶中的 Na(+)/K(+) 比值较低，AtHKT1 的表达水平显著受到抑制。我们的结果表明，PeNAC1 通过调节 Na(+)/K(+) 稳态在植物对盐胁迫的响应中发挥作用。
