The Role and Transcriptional Regulatory Mechanism of Rice OsGSTF5 in the Metabolism of Pretilachlor under Fenclorim Induction

Fenclorim (Fen), an herbicide safener, mitigates pretilachlor (Pre)-induced phytotoxicity in rice, although its molecular mechanism remains unclear. Previous studies have shown that Fen significantly induces <i>OsGSTF5</i> expression. This study revealed via molecular docking and in vitro assays that the OsGSTF5 protein binds to and metabolizes Pre. Unlike the wild-type plants, the <i>OsGSTF5</i>-overexpressing lines presented Pre tolerance. Cloning the <i>OsGSTF5</i> promoter (2.0 kb) identified a Fen-responsive cis-element (-1100 to -1500 bp). Yeast one-hybrid screening revealed that four transcription factors (EIL, AP2/ERF, DBB, and C2H2 families) bind the promoter, as validated by dual-luciferase and qRT-PCR assays. The research results establish a Fen (safener)-mediated detoxification network with <i>OsGSTF5</i> as the core, promoting our understanding of herbicide action mechanisms. Additionally, for the first time, this study clarifies the inductive regulatory mechanism of safeners in rice.