TdNF-YA2A-1transcription factor confers salt and osmotic stress tolerance in tobacco through regulation of the antioxidant defense system.

NF-YA1 (nuclear factor Y, subunit A1) is a key transcription factor that participates in the regulation of plant growth and stress responses. In plants, NF-YA proteins are encoded by multigene families and play crucial roles in controlling gene expression related to development, metabolism, and adaptation to environmental constraints. Therefore, NF-YA transcription factors are considered promising targets for improving plant tolerance to abiotic stress. In our previous study, we demonstrated that TdNF-YA2A-1 transcripts from durum wheat are induced by various abiotic stressors, and that heterologous expression of this gene enhances stress tolerance in yeast. Herein, we functionally investigated its role in transgenic tobacco. RT-qPCR analysis demonstrated that TdNF-YA2A-1 expression was differentially regulated in durum wheat tissues subjected to salt (150  mM NaCl), osmotic (10% PEG 8000), and oxidative (10 µM H₂O₂) stresses. Transgenic TdNFY-YA2A-1-overexpressing tobacco lines exhibited enhanced tolerance to both salt and osmotic stress relative with non-transgenic (NT) plants. This enhanced tolerance was correlated with a reduction in oxidative damage and the upregulation of several stress-responsive genes involved in antioxidant defense and stress signaling. Taken together, our results suggest that TdNF-YA2A-1 is a promising candidate gene for developing crops with improved tolerance to salt and osmotic stresses.