PeSTZ1, a C2H2-type zinc finger transcription factor from Populus euphratica, enhances freezing tolerance through modulation of ROS scavenging by directly regulating PeAPX2
PeSTZ1, a C2H2-type zinc finger transcription factor from Populus euphratica, enhances freezing tolerance through modulation of ROS scavenging by directly regulating PeAPX2
复制标题
PeSTZ1 是一种来自胡杨的 C2H2 型锌指转录因子，通过直接调节 PeAPX2 调节 ROS 清除来增强耐冻性
DOI：
10.1111/pbi.13130
复制
发表时间：
2019-11-01
影响因子：
13.8
通讯作者：
Xia, Xinli
中科院分区：
文献类型：
--
作者：
He, Fang;Li, Hui-Guang;Xia, Xinli
在本研究中，PeSTZ 1，半胱氨酸-2/组氨酸-2-型锌指转录因子，分离自沙漠白杨，胡杨，这是一个模式的压力适应系统的树木。PeSTZ 1优先在幼茎中表达，并在低温和冷冻处理期间显著上调。PeSTZ 1定位于细胞核，并特异性结合到PeAPX 2启动子。为了研究PeSTZ 1的潜在功能，我们在已知对胁迫敏感的84 K杨杂交种（银白杨x腺白杨）中过表达它。在冰冻胁迫下，转基因杨树比野生型杨树保持更高的光合活性，消耗更多的多余光能（以热的形式）。因此，PeSTZ 1作为转录激活因子发挥作用，以增强抗冻性而不牺牲生长。在冷冻胁迫下，PeSTZ 1作用于抗坏血酸过氧化物酶2（PeAPX 2）的上游，并通过结合其启动子直接调节其表达。活化的PeAPX 2促进细胞溶质APX，其在冷胁迫下清除活性氧（ROS）。PeSTZ 1可能与C-重复结合因子平行作用，调节冷调节基因表达。此外，PeSTZ 1上调通过激活抗氧化系统减少丙二醛和ROS积累。综上所述，这些结果表明，在84 K白杨中过表达PeSTZ 1通过直接调节PeAPX 2的表达来调节ROS清除，从而增强抗冻性。
In the present study, PeSTZ1, a cysteine-2/histidine-2-type zinc finger transcription factor, was isolated from the desert poplar, Populus euphratica, which serves as a model stress adaptation system for trees. PeSTZ1 was preferentially expressed in the young stems and was significantly up-regulated during chilling and freezing treatments. PeSTZ1 was localized to the nucleus and bound specifically to the PeAPX2 promoter. To examine the potential functions of PeSTZ1, we overexpressed it in poplar 84K hybrids (Populus alba x Populus glandulosa), which are known to be stress-sensitive. Upon exposure to freezing stress, transgenic poplars maintained higher photosynthetic activity and dissipated more excess light energy (in the form of heat) than wild-type poplars. Thus, PeSTZ1 functions as a transcription activator to enhance freezing tolerance without sacrificing growth. Under freezing stress, PeSTZ1 acts upstream of ASCORBATE PEROXIDASE2 (PeAPX2) and directly regulates its expression by binding to its promoter. Activated PeAPX2 promotes cytosolic APX that scavenges reactive oxygen species (ROS) under cold stress. PeSTZ1 may operate in parallel with C-REPEAT-BINDING FACTORS to regulate COLD-REGULATED gene expression. Moreover, PeSTZ1 up-regulation reduces malondialdehyde and ROS accumulation by activating the antioxidant system. Taken together, these results suggested that overexpressing PeSTZ1 in 84K poplar enhances freezing tolerance through the modulation of ROS scavenging via the direct regulation of PeAPX2 expression.