The basic leucine zipper transcription factor TabZIP156 interacts with jasmonate ZIM-domain protein TaJAZ3-2A to regulate drought response in wheat.

Drought represents a major abiotic factor that restricts crop yields worldwide. Previous studies have demonstrated that the wheat bZIP transcription factor TabZIP156 plays a vital role in enhancing drought tolerance. However, the drought tolerance mechanism of TabZIP156 in wheat remains unclear. In this study, TaJAZ3-2A was identified as an interactor of TabZIP156 through yeast two-hybrid screening. This interaction was confirmed in vivo using luciferase complementation imaging (LCI) and bimolecular fluorescence complementation, and further validated in vitro by GST pull-down experiments. The LCI assays showed that the C-terminal domain of TabZIP156 interacted with the N-terminal domain of TaJAZ3-2A. Transcription level analysis revealed that TaJAZ3-2A was predominantly expressed in roots, and exhibited significant response to PEG 6000-induced drought, ABA, and MeJA stress. Subcellular localization analysis showed that TaJAZ3-2A was localized to the nucleus. Functional studies revealed that TaJAZ3-2A overexpressing Arabidopsis displayed reduced drought tolerance. Conversely, virus-induced gene silencing of TaJAZ3-2A in wheat showed enhanced drought tolerance and upregulated key stress-responsive and antioxidant-related genes. Moreover, the dual-luciferase assays showed that TaJAZ3-2A and TabZIP156 mutually antagonize each other in regulating the expression levels of TaP5CS, TaDREB1A, and TaPOD. In conclusion, these findings provide novel mechanistic insights into the role of TabZIP156 in wheat drought tolerance and establish a theoretical foundation for the development of drought-tolerant wheat cultivars.