The C2H2-Type Zinc Finger Protein OsZFP179 Positively Regulates Cadmium Tolerance by Transcriptionally Activating OsGSTU19 in Rice

Abstract

Cadmium (Cd) contamination threatens rice quality and food safety. Although C2H2-type zinc finger proteins (ZFPs) regulate abiotic stress responses, their roles in rice Cd detoxification are largely unknown. Here, we show that OsZFP179 positively regulates Cd tolerance. OsZFP179 is Cd-inducible and nuclear-localized. Its loss-of-function mutants display Cd hypersensitivity, reduced Cd accumulation, and increased oxidative damage, while complementation restores the wild-type phenotype. Transcriptome analysis reveals that Cd-induced expression of OsGSTU19, a glutathione S-transferase gene, depends on OsZFP179. Mechanistically, OsZFP179 directly binds AG-rich motifs in the OsGSTU19 promoter to activate its transcription, as supported by ChIP-qPCR, EMSA, Y1H, and dual-luciferase assays. Importantly, OsGSTU19 overexpression rescues the Cd-sensitive phenotype of oszfp179. Together, our findings establish the OsZFP179–OsGSTU19 module as a novel pathway enhancing Cd tolerance in rice, offering potential targets for breeding low-Cd varieties.