NO- and H2S-derived post-translational modifications and stress resilience.

Nitric oxide (NO) and hydrogen sulfide (H2S) have emerged as key gaseous signaling molecules in plants, playing central roles in regulating responses to a myriad of abiotic stresses. A major mechanism through which these molecules exert their effects is via post-translational modifications (PTMs) of proteins, including tyrosine nitration, S-nitrosation, and persulfidation. The last two correspond to redox-based modifications (oxiPTMs) that can rapidly and reversibly alter protein activity, stability, localization, and interactions, thereby enabling dynamic cellular reprogramming under stress conditions. Recent advances have highlighted the intricate crosstalk between NO- and H2S-mediated PTMs, revealing a complex regulatory network that fine-tunes stress signaling pathways and enhances plant resilience. Understanding how these modifications integrate environmental cues with cellular and subcellular responses provides new insights into the molecular basis of stress tolerance and offers potential strategies for improving crop performance under adverse conditions.