Hydrogen sulfide and protein persulfidation in plant stress signaling

Hydrogen sulfide (H2S) is increasingly recognized as a crucial signaling molecule in plants that plays key roles in regulating physiological processes and enhancing stress tolerance. This review provides an updated summary of H2S signaling in plant stress responses, and discusses its uptake from external environmental sources, its endogenous biosynthesis, and its broader functions in stress adaptation. We summarize the impact of H2S on plants under various stress conditions and review the mechanisms through which it mediates signaling functions, with a particular focus on H2S-mediated protein persulfidation. In addition, we provide an overview of the current understanding of protein persulfidation in regulating physiological processes and stress responses in plants, offering both a general discussion of its effects under different stress conditions and specific examples to highlight its significance. Finally, we review recent proteomic studies on protein persulfidation in plants, comparing the identified persulfidated proteins across studies and highlighting shared biological processes and pathways. This review aims to consolidate our current understanding of H2S signaling and its roles as mediated by protein persulfidation in plants, while also offering insights to inspire future research in this rapidly evolving field.