Over-Expression of a Maize N -Acetylglutamate Kinase Gene ( ZmNAGK ) Improves Drought Tolerance in Tobacco

• Published in: Frontiers in plant science Vol. 9; p. 1902
• Main Authors: Liu, Weijuan, Xiang, Yang, Zhang, Xiaoyun, Han, Gaoqiang, Sun, Xiujuan, Sheng, Yu, Yan, Jingwei, Scheller, Henrik Vibe, Zhang, Aying
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 04.01.2019; Frontiers Media S.A
• Subjects: abiotic stress; arginine; drought stress; ENVIRONMENTAL SCIENCES; Plant Science; tobacco; ZmNAGK; NO; ZmNAGK; tobacco; arginine; drought stress; abiotic stress
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2018.01902

Water deficit is a key limiting factor that affects the growth, development and productivity of crops. It is vital to understand the mechanisms by which plants respond to drought stress. Here an -acetylglutamate kinase gene, , was cloned from maize ( ). was expressed at high levels in maize leaves and at lower levels in root, stem, female flower and male flower. The expression of was significantly induced by PEG, NaCl, ABA, brassinosteroid and H O . The ectopic expression of in tobacco resulted in higher tolerance to drought compared to plants transformed with empty vector. Further physiological analysis revealed that overexpression of could enhance the activities of antioxidant defense enzymes, and decrease malondialdehyde content and leakage of electrolyte in tobacco under drought stress. Moreover, the transgenic tobacco accumulated more arginine and nitric oxide (NO) than control plants under drought stress. In addition, the transgenic tobaccos activated drought responses faster than vector-transformed plants. These results indicate that can play a vital role in enhancing drought tolerance by likely affecting the arginine and NO accumulation, and could be involved in different strategies in response to drought stress.