摘要
盐胁迫能够加速草坪草的黄化,影响草坪的坪观质量。植物中的NAC转录因子在盐胁迫条件下发挥着重要作用,参与胁迫响应,而在日本结缕草(Zoysia japonica)中还鲜有NAC转录因子的功能研究。本研究对转ZjNAC3基因(GenBank登录号:MT254544)的YPH500酵母菌株进行盐敏感性检测,初步判定ZjNAC3在盐胁迫下具有负调节酵母细胞生长的作用;对过表达ZjNAC3基因的拟南芥(Arabidopsis thaliana)株系进行盐处理,发现150 mmol·L^(−1) NaCl处理7 d后转基因植株的生长明显弱于野生型(wild type,WT),脯氨酸含量、丙二醛含量、细胞膜透性均显著高于WT(P<0.05),而叶绿素、可溶性糖含量显著低于WT(P<0.05);AtNHX1基因的表达量显著低于WT(P<0.05),表明过表达ZjNAC3基因降低了拟南芥植株的耐盐性。分析认为ZjNAC3通过减弱渗透调节、增加细胞受损和降低将Na+隔离到液泡的作用,从而使得转基因拟南芥植株表现出盐敏感的性状。本研究揭示了ZjNAC3是一个负调控植物耐盐性的重要基因,为之后探究NAC转录因子调控日本结缕草的耐盐性及其机理奠定了基础。
Salt stress can accelerate the rate of yellowing and affect the overall value of turfgrass.Although NAC transcription factors have been reported to play important roles in plant salt tolerance,only a few studies have described the functional characterization of NAC genes in Zoysia japonica.In this study,we used yeast strain YPH500 transformed with the ZjNAC3 gene to evaluate the contribution of this gene to salt stress tolerance.Our preliminary data determined that ZjNAC3 negatively regulates yeast cell growth during salt stress with this being further confirmed in a transgenic Arabidopsis thaliana treated with salt.Our analysis showed that the growth of these transgenic plants was significantly weaker than wildtype(WT)plants after 7 days of treatment with 150 mmol·L^(−1) NaCl.Proline,MDA content,and cell membrane permeability were also all significantly higher in ZjNAC3−overexpressing lines than in WT(P<0.05),whereas chlorophyll and soluble sugar content was decreased in transgenic plants(P<0.05).In addition,the expression of AtNHX1 in the transgenic lines was significantly lower than that in WT plants(P<0.05).Taken together,these data indicate that the overexpression of the ZjNAC3 gene decreases salt tolerance in Arabidopsis plants.It is thus rational to deduce that the decline in osmotic regulation,severe cell damage,and weakened ability to isolate Na+into vacuoles all contribute to the salt-sensitive phenotype of these transgenic Arabidopsis plants.This study revealed that ZjNAC3 is an important gene regulating salt stress tolerance and lays the foundation for the future exploration of NAC transcription factors in Zoysia japonica.
作者
姜红岩
范希峰
温海峰
韩朝
滕文军
滕珂
尹淑霞
JIANG Hongyan;FAN Xifeng;WEN Haifeng;HAN Chao;TENG Wenjun;TENG Ke;YIN Shuxia(Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China;School of Grassland Science,Beijing Forestry University,Beijing 100083,China)
出处
《草业科学》
CAS
CSCD
北大核心
2021年第9期1706-1714,共9页
Pratacultural Science
基金
国家自然科学基金(31901397)
北京市自然科学基金(6204039)
北京市农林科学院创新能力建设专项(KJCX20210431)。
关键词
日本结缕草
NAC转录因子
转基因拟南芥
转基因酵母
盐胁迫
渗透调节
基因表达
Zoysia japonica
NAC transcription factor
transgenic Arabidopsis thaliana
transgenic yeast
salt stress
osmotic adjustment
gene expression
