Fecha de publicación: -- Fuente: PubMed "rice" Plant Physiol Biochem. 2026 Nov 6;240:111939. doi: 10.1016/j.plaphy.2026.111939. Online ahead of print.ABSTRACTSoil salinity severely limits plant growth and productivity through osmotic stress, ion toxicity, and excessive accumulation of reactive oxygen species (ROS). Although TIFY proteins regulate plant responses to environmental stresses, their roles in salt tolerance in foxtail millet (Setaria italica) remain poorly understood. Here, we characterized SiTIFY9 (Seita.9G51810) through phylogenetic analysis, expression profiling, subcellular localization, transcriptional activation assays, stable overexpression, physiological measurements, and transcriptome sequencing. SiTIFY9 clustered with rice OsTIFY11a/OsJAZ9, localized predominantly to the nucleus, and exhibited no autonomous transcriptional activation activity in yeast. Under salt stress, SiTIFY9-overexpressing plants showed reduced hydrogen peroxide and malondialdehyde accumulation, increased catalase and peroxidase activities, and enhanced proline accumulation compared with wild-type plants. Overexpression also restricted Na+ accumulation, promoted K+ retention, and increased the K+/Na+ ratio, indicating improved ionic homeostasis. Transcriptome analysis revealed extensive transcriptional changes associated with stress responses, redox regulation, ion transport, phenylpropanoid biosynthesis, carbohydrate metabolism, and secondary metabolism. RT-qPCR further confirmed altered expression of genes involved in ion transport, osmoprotection, transcriptional regulation, and stress defense. Independently, SiTIFY9-overexpressing plants flowered 14-16 days earlier than wild-type plants under non-saline conditions, suggesting an additional role in flowering-time regulation. Collectively, these findings demonstrate that SiTIFY9 overexpression enhances salt tolerance by improving antioxidant defense, osmotic adjustment, and ionic homeostasis, accompanied by transcriptional reprogramming of stress-responsive pathways. Furthermore, its association with earlier flowering suggests a potential developmental function. This study identifies SiTIFY9 as a promising candidate for further investigation of salt-stress tolerance and flowering-time regulation in foxtail millet.PMID:43000025 | DOI:10.1016/j.plaphy.2026.111939