IDR1 links chloroplast redox control to sustained drought tolerance: a stage-resolved transcriptomic study

Drought stress is one of the major environmental factors limiting rice productivity. The heterotrimeric G-protein \u03b1 subunit IDR1 (RGA1) has been implicated in multiple abiotic stress responses, yet its stage-specific regulatory roles under drought remain unclear. Here, we performed stage-resolved transcriptomic analyses using rice leaves collected at two defined drought stages, early and mid, distinguished by visible leaf rolling degree, from idr1-1 and wild-type IAPAR9 plants with three biological replicates per treatment. Differentially expressed genes (DEGs) were identified and integrated through overlap-based analysis to prioritize IDR1-associated drought-responsive components. Functional enrichment revealed that overlap-derived genes were preferentially associated with chloroplast organization, photosynthetic electron transport, and redox-related processes, with stronger enrichment at the mid-stage drought stage.