Molecular insights into drought tolerance in wheat through in-silico genome-wide analysis of DREB1 transcription factor and peroxidase interactions
Lubaba Komal, Atif Kamran, Summera Jahan, Waheed Akram, Manzer H. Siddiqui, Saud Alamri, Muhammad Zeeshan Shakir
Abstract
Wheat (Triticum aestivum) is a staple food crop providing essential nutrition to global population. However, water scarcity and increasing drought stress, because of climate change, threaten its productivity. Oxidative stress increases the production of reactive oxygen species (ROS) due to drought which damages the plant cellular metabolism. Plants counteract this by regulating the transcription of enzymes like catalases, peroxidases, and superoxide dismutase. This research investigated activated biochar's (AB) role on wheat cultivars under deficit irrigation. Activated biochar significantly reduced lipid peroxidation (27-56%) while increasing antioxidant activities (40-60%) under low irrigation as compared to the control (no biochar), suggesting its potential to improve drought resilience. Peroxidase, for presenting significantly higher antioxidant activity, was selected as a key enzyme for molecular docking. Protein-protein interactions between the DREB1 transcription factor and peroxidase, supported by hydrogen bonding, electrostatic interactions, and hydrophobic forces, highlighted the role of biochar mediated peroxidase in oxidative stress response. This interaction highlighted the role of DREB1 in drought resilience, presenting a range of protein sizes, isoelectric points, and stability indices across TaDREB proteins in the wheat genome. Subcellular localization analysis demonstrated that most TaDREB genes, particularly DREB1, are active in the nucleus. At the same time, some are localized to chloroplasts and mitochondria, suggesting diverse roles in stress response and energy metabolism. Phylogenetic analysis grouped DREB genes from wheat (TaDREB), maize (ZmDREB), and Arabidopsis (AtDREB), indicating conserved evolutionary functions across monocot and dicot species. Motif and domain prediction revealed conserved AP2 domains across TaDREB genes, emphasizing their structural and functional conservation, which likely evolved through gene expansion to enhance stress tolerance. These findings are crucial for understanding biochemical attributes of drought responsive transcription factors and their interactive response with antioxidants, which can further help in gene editing technology.