TaNAC29, a NAC transcription factor from wheat, enhances salt and drought tolerance in transgenic Arabidopsis. Issue 1 (December 2015)

• Record Type: Journal Article
• Authors: Huang, Quanjun; Wang, Yan; Li, Bin; Chang, Junli; Chen, Mingjie; Li, Kexiu; Yang, Guangxiao; He, Guangyuan
• Is Part Of: BMC plant biology. Volume 15:Issue 1(2015)
• Page Start: 1
• Page End: 15
• Publication Date: 2015-12
• Subjects: Wheat -- Arabidopsis -- NAC -- TaNAC29 -- Abiotic stress -- ABA-hypersensitive; Plant molecular biology -- Periodicals; Botany -- Periodicals; 580.5
• DOI: 10.1186/s12870-015-0644-9
• Languages: English
• ISSNs: 1471-2229

Abstract

Abstract Background NAC (NAM, ATAF, and CUC) transcription factors play important roles in plant biological processes, including phytohormone homeostasis, plant development, and in responses to various environmental stresses. Methods TaNAC29 was introduced intoArabidopsis using theAgrobacterium tumefaciens -mediated floral dipping method.TaNAC29 -overexpression plants were subjected to salt and drought stresses for examining gene functions. To investigate tolerant mechanisms involved in the salt and drought responses, expression of related marker genes analyses were conducted, and related physiological indices were also measured. Expressions of genes were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Results A novel NAC transcription factor gene, designatedTaNAC29, was isolated from bread wheat (Triticum aestivum ). Sequence alignment suggested thatTaNAC29 might be located on chromosome 2BS. TaNAC29 was localized to the nucleus in wheat protoplasts, and proved to have transcriptional activation activities in yeast.TaNAC29 was expressed at a higher level in the leaves, and expression levels were much higher in senescent leaves, indicating thatTaNAC29 might be involved in the senescence process.TaNAC29 transcripts were increased following treatments with salt, PEG6000, H2 O2, and abscisic acid (ABA). To examineTaNAC29 function, transgenicArabidopsis plants overexpressingTaNAC29 were generated. Germination and root length assays of transgenic plants demonstrated thatTaNAC29 overexpression plants had enhanced tolerances to high salinity and dehydration, and exhibited an ABA-hypersensitive response. When grown in the greenhouse, TaNAC29 -overexpression plants showed the same tolerance response to salt and drought stresses at both the vegetative and reproductive period, and had delayed bolting and flowering in the reproductive period. Moreover, TaNAC29 overexpression plants accumulated lesser malondialdehyde (MDA), H2 O2, while had higher superoxide dismutase (SOD) and catalase (CAT) activities under high salinity and/or dehydration stress. Conclusions Our results demonstrate thatTaNAC29 plays important roles in the senescence process and response to salt and drought stresses. ABA signal pathway and antioxidant enzyme systems are involved in TaNAC29-mediated stress tolerance mechanisms.