PvPR10-3 Expression Confers Salt Stress Tolerance in Arabidopsis and Interferes with Jasmonic Acid and ABA Signaling

Salt stress is a major abiotic factor limiting crop productivity worldwide, as it disrupts plant growth, metabolism, and survival. In this study, we report that the genes PvPR10-2 and PvPR10-3 were significantly up-regulated in bean leaves and stems in response to combined salt and jasmonic acid (NaCl-JA) treatment. Foliar application of JA with salt induced physiological alterations, including stem growth inhibition, H₂O₂ accumulation, and activation of antioxidant enzymes. To investigate the role of PvPR10-3 in response to salt and phytohormones, we introduced this gene into Arabidopsis and found that its heterologous expression conferred salt tolerance to the transgenic lines. Interestingly, exogenous JA contributed to salt tolerance by reducing H₂O₂ levels, inducing ROS-scavenging enzymes, and promoting the accumulation of phenolic compounds and ABA. Furthermore, gene expression analysis of the transgenic lines revealed that PvPR10-3 expression under NaCl-JA stress is associated with the induction of JA-related genes like MYC2, JAZ2, JAZ11, and JAZ12, as well as SA-responsive genes, like ALD1 and TGA2, and two ABA-independent components DREB2A and ERD1, suggesting potential coordination between JA, ABA, and SA signaling in salt stress response. Additionally, key flowering regulators (FT, GI) were upregulated in transgenic lines under NaCl-JA treatment, suggesting a previously unexplored link between salt tolerance pathways and the regulation of flowering time. Taken together, our findings suggest a role of PvPR10-3 in enhancing salt stress tolerance and the involvement of exogenous JA in tolerance potentially by modulating ROS balance, hormone-associated gene expression, and protective secondary metabolites.