GmNAC06, a NAC domain transcription factor enhances salt stress tolerance in soybean

Abstract

Key message We found GmNAC06 plays an important role in salt stress responses through the phenotypic, physiological and molecular analyses of OE, VC, and Mutant composite soybean. Abstract Salinization affects 20% of all cultivated land worldwide because of the high salinity of irrigation water and the excessive use of water, and this amount is increasing daily. NAC (NAM, ATAF, and CUC) have been found to be involved in salt stress. In this study, a soybean NAC gene, GmNAC06 (Glyma06g21020.1), was cloned and functionally characterized. The results of expression analysis suggested that salt stress could influence the expression level of GmNAC06. The subcellular localization analysis results suggested that GmNAC06 may function as a transcription factor. Under salt stress, the overexpression technology combined with CRISPR-Cas9 system found that GmNAC06 could cause the accumulation of proline and glycine betaine to alleviate or avoid the negative effects of ROS; similarly, it could control the Na+/K+ ratios in hairy roots to maintain ionic homeostasis. The fresh weight of the transgenic hairy roots and the histochemical ROS staining of wild leaves suggested that transgenic hairy roots influence the function of wild leaves under salt stress conditions. Moreover, the expression levels of GmUBC2 and GmHKT1 were higher in the GmNAC06 hairy roots than in the control. Thus, the overexpression of GmNAC06 in hairy roots notably causes an entire composite plant to exhibit salt tolerance. The phenotype of composite soybean plants and transgenic Arabidopsis plants suggest that GmNAC06 plays a role in response to salt stress and could be useful in generating salt tolerant transgenic crops.

Genome-Wide Identification of NAC Transcription Factor Family in Juglans mandshurica and Their Expression Analysis during the Fruit Development and Ripening

“…A large number of NAC-encoding genes have been identified and confirmed in various plants for their role in regulating wood formation [14], leaf senescence [15], fruit development [16,17], and flower morphogenesis [18,19]. Furthermore, NAC TFs also are involved in various biotic and abiotic stress responses in many plants such as Populus tomentosa [20], Arabidopsis thaliana [21], Oryza sativa [22,23], Glycine max [24], Arachis hypogaea [25], and Xanthoceras sorbifolia [26]. The overexpression of many NAC genes increases stress tolerance in plants.…”

Next-Generation Breeding Strategies for Climate-Ready Crops

“…The study indicated a direct function of the OsNAC041 gene under salt stress and can offer an excellent potential to target other NAC genes for rice-resistant breeding (Bo et al, 2019 ). Similarly, another NAC gene GmNAC06 was targeted by using CRISPR/Cas9-based gene editing and overexpression technology in soybean, and the results demonstrated that the GmNAC06 gene improved the salinity tolerance by alleviating ROS effects, accumulating glycine betaine and proline, and maintaining ionic homeostasis (Li et al, 2021 ).…”

AvNAC030, a NAC Domain Transcription Factor, Enhances Salt Stress Tolerance in Kiwifruit

“…After overexpression of OoNAC72 in Arabidopsis thaliana, Guan et al found that transgenic plants carry out osmotic regulation and remove ROS after salt stress so as to reduce peroxidation damage [31]. Li et al used gene editing combined with genetic transformation and other molecular biology techniques and found that GmNAC06 could reduce the content of ROS in plants through the accumulation of osmotic mediating substances, thereby increasing the salt tolerance of plants [32].…”