Hydrogen Sulfide in the Oxidative Stress Response of Plants: Crosstalk with Reactive Oxygen Species

Growing evidence suggests that exposure of plants to unfavorable environments leads to the accumulation of hydrogen sulfide (H₂S) and reactive oxygen species (ROS). H₂S interacts with the ROS-mediated oxidative stress response network at multiple levels. Therefore, it is essential to elucidate the mechanisms by which H₂S and ROS interact. The molecular mechanism of action by H₂S relies on the post-translational modification of the cysteine sulfur group (-SH), known as persulfidation. H₂S cannot react directly with -SH, but it can react with oxidized cysteine residues, and this oxidation process is induced by H₂O₂. Evidently, ROS is involved in the signaling pathway of H₂S and plays a significant role. In this review, we summarize the role of H₂S-mediated post-translational modification mechanisms in oxidative stress responses. Moreover, the mechanism of interaction between H₂S and ROS in the regulation of redox reactions is focused upon, and the positive cooperative role of H₂S and ROS is elucidated. Subsequently, based on the existing evidence and clues, we propose some potential problems and new clues to be explored, which are crucial for the development of the crosstalk mechanism of H₂S and ROS in plants.