WRKY13 Enhances Cadmium Tolerance by Promoting and Hydrogen Sulfide Production.

Hydrogen sulfide (HS), a plant gasotransmitter, functions in the plant response to cadmium (Cd) stress, implying a role for cysteine desulfhydrase in producing HS in this process. Whether () acts in the plant Cd response remains to be identified, and if it does, how is regulated in this process is also unknown. Here, we report that -mediated HS production enhances plant Cd tolerance in Arabidopsis (). When subjected to Cd stress, a mutant accumulated more Cd and reactive oxygen species and showed increased Cd sensitivity, whereas transgenic lines overexpressing had decreased Cd and reactive oxygen species levels and were more tolerant to Cd stress compared with wild-type plants. Furthermore, the expression of was stimulated by Cd stress, and this up-regulation was mediated by a Cd-induced transcription factor, WRKY13, which bound to the promoter. Consistently, the higher Cd sensitivity of the mutant was rescued by the overexpression of Together, our results demonstrate that Cd-induced WRKY13 activates expression to increase the production of HS, leading to higher Cd tolerance in plants.