Overexpression of the WRKY transcription factor gene NtWRKY65 enhances salt tolerance in tobacco (Nicotiana tabacum)

• Published in: BMC plant biology Vol. 24; no. 1; p. 326
• Main Authors: Zhang, Xiaoquan, Zhang, Yaxuan, Li, Man, Jia, Hongfang, Wei, Fengjie, Xia, Zongliang, Zhang, Xuelin, Chang, Jianbo, Wang, Zhaojun
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 24.04.2024; BioMed Central; BMC
• Subjects: Abiotic stress; Analysis; antioxidant enzymes; Antioxidants; auxins; cell wall components; Cell walls; Cellular stress response; chlorophyll; Cultivars; Detoxification; Diseases and pests; Electrolyte leakage; Environmental aspects; Enzymatic activity; Enzyme activity; Enzymes; family; Gene expression; Gene Expression Regulation, Plant; Genes; Genetic aspects; genetically modified organisms; Growth; Leaf area; Leaves; malondialdehyde; metabolism; Nicotiana - genetics; Nicotiana - physiology; Nicotiana tabacum; NtWRKY65; Osmotic stress; Oxidants; Oxidizing agents; Phosphorylation; Physiology; Plant growth; Plant Proteins - genetics; Plant Proteins - metabolism; Plants, Genetically Modified - genetics; protein phosphorylation; Proteins; Salinity; Salinity effects; Salinity tolerance; Salt; salt stress; Salt stress (Botany); Salt tolerance; Salt Tolerance - genetics; sequence analysis; Signal transduction; Sodium chloride; stress response; stress tolerance; Tobacco; Tobacco (Plant); Tobacco plants; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; transcriptional activation; Transgenic plants; WRKY family transcription factor; Yeast; China; WRKY family transcription factor; Salt tolerance; NtWRKY65; Tobacco plants
• DOI: 10.1186/s12870-024-04966-0
• ISSN: 1471-2229

Salt stress severely inhibits plant growth, and the WRKY family transcription factors play important roles in salt stress resistance. In this study, we aimed to characterize the role of tobacco (Nicotiana tabacum) NtWRKY65 transcription factor gene in salinity tolerance. This study characterized the role of tobacco (Nicotiana tabacum) NtWRKY65 transcription factor gene in salinity tolerance using four NtWRKY65 overexpression lines. NtWRKY65 is localized to the nucleus, has transactivation activity, and is upregulated by NaCl treatment. Salinity treatment resulted in the overexpressing transgenic tobacco lines generating significantly longer roots, with larger leaf area, higher fresh weight, and greater chlorophyll content than those of wild type (WT) plants. Moreover, the overexpressing lines showed elevated antioxidant enzyme activity, reduced malondialdehyde content, and leaf electrolyte leakage. In addition, the Na content significantly decreased, and the K /Na ratio was increased in the NtWRKY65 overexpression lines compared to those in the WT. These results suggest that NtWRKY65 overexpression enhances salinity tolerance in transgenic plants. RNA-Seq analysis of the NtWRKY65 overexpressing and WT plants revealed that NtWRKY65 might regulate the expression of genes involved in the salt stress response, including cell wall component metabolism, osmotic stress response, cellular oxidant detoxification, protein phosphorylation, and the auxin signaling pathway. These results were consistent with the morphological and physiological data. These findings indicate that NtWRKY65 overexpression confers enhanced salinity tolerance. Our results indicated that NtWRKY65 is a critical regulator of salinity tolerance in tobacco plants.