The OsGSK1–OsBZR3–OsJAZ4 module integrates nitrate signaling with brassinosteroid and jasmonic acid crosstalk to drive cell wall remodeling for salt recovery in rice

Abstract

Salinity stress severely limits rice productivity. Understanding how crops sustain growth during prolonged salt stress is therefore of critical importance. Here, we demonstrate that a brassinosteroid (BR)–jasmonic acid (JA) signaling network integrates nitrate signals to remodel root cell walls and promote salt recovery in rice ( Oryza sativa ). The GSK3-like kinase OsGSK1 interacts with and phosphorylates the transcription factor BRASSINAZOLE-RESISTANT 3 (OsBZR3), which negatively regulates root growth recovery and seedling survival under prolonged salt stress. OsBZR3 fine-tunes root cell wall thickening and compositional remodeling, as well as the nitrate response in rice under salt stress. Notably, high nitrate supply represses the salt-stress-induced phosphorylation of OsBZR3 by OsGSK1. OsBZR3 acts upstream of the JA signaling repressor Jasmonate ZIM-domain 4 (OsJAZ4) by directly binding to its promoter region. The OsGSK1–OsBZR3 module regulates OsJAZ4 activity to orchestrate the expression of downstream cell wall remodeling genes under salt stress. Our findings establish the OsGSK1–OsBZR3–OsJAZ4 module as a potential hub integrating nitrate and hormonal signals under prolonged salt stress and identify novel key genetic targets for breeding salt-resilient crops, thus advancing sustainable agricultural practices.