TaGATA5 acts as a positive regulator of drought tolerance in wheat.

Abstract

Drought poses a serious challenge to global crop production. Identifying drought tolerance genes underpins the breeding of drought-resilient crop varieties. GATA transcription factors (TFs) are recognized as crucial modulators of plant abiotic stress responses, yet their specific functions in common wheat remain largely unexplored. In this study, we identified the TF TaGATA5, which encodes a protein containing a conserved ZnF_GATA domain across plant species. The expression of TaGATA5 was markedly induced by PEG, NaCl, and abscisic acid (ABA) treatments in wheat. Subcellular localization analysis showed that TaGATA5 was localized to the nucleus, and transactivation assays demonstrated its transcriptional activation ability. Compared with wild-type controls, TaGATA5 transgenic plants displayed improved growth performance and higher survival rates under drought stress by reducing water loss and maintaining higher relative water content. Moreover, TaGATA5 overexpression reduced reactive oxygen species (ROS) accumulation and malondialdehyde (MDA) content, accompanied by increased superoxide dismutase (SOD) activity. Conversely, TaGATA5 knockout mutants showed compromised drought tolerance, characterized by reduced growth performance, increased water loss, and lower survival rates. Yeast two-hybrid screening identified TaCOP9-2A as an interacting partner of TaGATA5. Both TaGATA5 and TaCOP9-2A function as positive regulators of drought tolerance. Notably, no negative effects on yield-related traits were observed in TaGATA5 transgenic plants under greenhouse conditions. Collectively, our findings elucidate the biological function of TaGATA5 in the wheat drought stress response and provide a valuable genetic resource for breeding drought-tolerant wheat varieties.