Zhang Jiaxin, Movahedi Ali, Sang Ming, Wei Zhiheng, Xu Junjie, Wang Xiaoli, Wu Xiaolong, Wang Mengyang, Yin Tongming, Zhuge Qiang
Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing 210037, China.
Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing 210037, China.
Plant Physiol Biochem. 2017 Aug;117:61-74. doi: 10.1016/j.plaphy.2017.05.019. Epub 2017 May 31.
Nucleoside diphosphate kinases (NDPKs) are multifunctional proteins that regulate a variety of eukaryotic cellular activities, including cell proliferation, development, and differentiation. NDPK2 regulates the expression of antioxidant genes in plants. In a previous study, the Arabidopsis thaliana NDPK2 gene (AtNDPK2) was found to be associated with HO-mediated mitogen-activated protein kinase signaling in Arabidopsis thaliana. Proteins from transgenic plants overexpressing AtNDPK2 showed higher levels of autophosphorylation and NDPK activity and lower levels of reactive oxygen species (ROS) than those of wild-type (WT) plants. Therefore, constitutive overexpression of AtNDPK2 in Arabidopsis plants conferred enhanced tolerance to multiple environmental stresses that elicit ROS accumulation in situ. In this study, we cloned the Populus trichocarpa NDPK2 gene and analyzed its molecular structure and function. We generated and evaluated transgenic poplar plants expressing the PtNDPK2 gene under the control of the 35S promoter to achieve enhanced tolerance to various abiotic stresses. Transgenic poplar plants showed enhanced tolerance to salt and drought stress at the whole-plant level. The transgenic poplar plants showed significantly greater tolerance to 200 mM NaCl and drought stresses than WT poplar plants. In addition, the transgenic plants exhibited better growth due to increased expression of auxin-related indole acetic acid genes under normal growth conditions compared with WT plants. Our results suggest that induction of PtNDPK2 overexpression in poplars will be useful for increasing biomass production in the presence of various abiotic stresses.
核苷二磷酸激酶（NDPKs）是多功能蛋白质，可调节多种真核细胞活动，包括细胞增殖、发育和分化。NDPK2调节植物中抗氧化基因的表达。在先前的一项研究中，发现拟南芥NDPK2基因（AtNDPK2）与拟南芥中HO介导的丝裂原活化蛋白激酶信号传导有关。与野生型（WT）植物相比，过表达AtNDPK2的转基因植物中的蛋白质显示出更高水平的自磷酸化和NDPK活性以及更低水平的活性氧（ROS）。因此，拟南芥植物中AtNDPK2的组成型过表达赋予了对多种环境胁迫的增强耐受性，这些胁迫会原位引发ROS积累。在本研究中，我们克隆了毛果杨NDPK2基因并分析了其分子结构和功能。我们生成并评估了在35S启动子控制下表达PtNDPK2基因的转基因杨树植物，以实现对各种非生物胁迫的增强耐受性。转基因杨树植物在全株水平上表现出对盐和干旱胁迫的增强耐受性。转基因杨树植物对200 mM NaCl和干旱胁迫的耐受性明显高于WT杨树植物。此外，与WT植物相比，转基因植物在正常生长条件下由于生长素相关的吲哚乙酸基因表达增加而表现出更好的生长。我们的结果表明，在杨树中诱导PtNDPK2过表达将有助于在存在各种非生物胁迫的情况下增加生物量产量。
