title: AtTGA4, a bZIP transcription factor, confers drought resistance by enhancing nitrate transport and assimilation in Arabidopsis thaliana.
abstract: To cope with environmental stress caused by global climate change and excessive nitrogen application, it is important to improve water and nitrogen use efficiencies in crop plants. It has been reported that higher nitrogen uptake could alleviate the damaging impact of drought stress. However, there is scant evidence to explain how nitrogen uptake affects drought resistance. In this study we observed that bZIP transcription factor AtTGA4 (TGACG motif-binding factor 4) was induced by both drought and low nitrogen stresses, and that overexpression of AtTGA4 simultaneously improved drought resistance and reduced nitrogen starvation in Arabidopsis. Following drought stress there were higher nitrogen and proline contents in transgenic AtTGA4 plants than in wild type controls, and activity of the key enzyme nitrite reductase (NIR) involved in nitrate assimilation processes was also higher. Expressions of the high-affinity nitrate transporter genes NRT2.1 and NRT2.2 and nitrate reductase genes NIA1 and NIA2 in transgenic plants were all higher than in wild type indicating that higher levels of nitrate transport and assimilation activity contributed to enhanced drought resistance of AtTGA4 transgenic plants. Thus genetic transformation with AtTGA4 may provide a new approach to simultaneously improve crop tolerance to drought and low nitrogen stresses.
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Guizhou Institute of Prataculture, Guizhou Academy of Agricultural Sciences, Guiyang, Guizhou 550006, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhong
authors.affiliation: College of Life Sciences, Northwest A&F University, Yangling, Shanxi 712100, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Chen
authors.affiliation: College of Life Sciences, Northwest A&F University, Yangling, Shanxi 712100, China.
authors.forename: Donghong
authors.initials: D
authors.lastname: Min
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Li
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Zhaoshi
authors.initials: Z
authors.lastname: Xu
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Liancheng
authors.initials: L
authors.lastname: Li
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address: chenming02@caas.cn.
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Youzhi
authors.initials: Y
authors.lastname: Ma
mesh_terms: D027321:Anion Transport Proteins / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism*; D057231:Climate Change; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D000091285:Nitrate Transporters; D009566:Nitrates / Q000378:metabolism*; D009572:Nitrite Reductases / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D013312:Stress, Physiological
chemical_list: D027321:Anion Transport Proteins; D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D000091285:Nitrate Transporters; D009566:Nitrates; D009572:Nitrite Reductases; C477335:NRT2.1 protein, Arabidopsis; C493954:NRT2.2 protein, Arabidopsis; C000588818:TGA4 protein, Arabidopsis
keywords: Arabidopsis thaliana; Drought stress; Low nitrogen stress; Nitrogen absorption; Transcription factor