The integration of environmental and developmental cues into coherent physiological responses is fundamental to plant survival. Reactive oxygen, nitrogen, and sulfur species (ROS/RNS/RSS) are now recognized as essential signaling molecules, not merely cytotoxic byproducts. Their specificity is largely achieved through reversible, site-specific cysteine oxidative post-translational modifications (Cys-OxiPTMs), which constitute a dynamic and sophisticated "redox code". This review provides a systematic synthesis of the current landscape of Cys-OxiPTMs in plants, bridging chemistry, hormone biology, agronomy, detection, and engineering. The chemical and enzymatic basis of major Cys-OxiPTMs is detailed, along with a discussion of how their spatiotemporal interplay orchestrates signaling specificity. A critical examination is then presented on how these modifications decode and integrate plant hormone signaling networks to regulate key agronomic traits. Cutting-edge proteomic technologies that have revolutionized the identification of redox-sensitive cysteines are also evaluated. Finally, forward-looking strategies to "write" the redox code are explored. By moving the field from descriptive cataloging to predictive "redox breeding," this review establishes a foundational framework for manipulating Cys-OxiPTMs to develop climate-resilient, high-yielding crops for sustainable agriculture.
Dan Zhao, Feifei Huang, Haimiao Zhang et al.· Journal of genetics and geno...· 0 citations
Redox regulation plays an important role in plant stress responses. Our previous study revealed that rice GLUTATHIONE PEROXIDASE 1 (GPX1) acts as a redox sensor and transducer and promotes osmotic stress tolerance by transfer of cytosolic oxidative signals to transcription factor BASIC LEUCINE ZIPPER 68 (bZIP68). However, the mechanisms governing GPX1 activity and nuclear localization remain unclear. Here, we show that osmotic stress increases GPX1 acetylation. Peroxidase activity and subcellular localization assay indicated that the effects of acetylation on GPX1 function are site-specific, as the acetylation of K94 and K121 enhances GPX1 enzymatic activity, whereas the C-terminal K159/K162/K163 cluster is required for its nuclear translocation. Transgenic complementation and physiological assays confirmed that substitution of K159/K162/K163 sites into arginine abolished GPX1-mediated osmotic stress tolerance and the activation of bZIP68 target genes. Furthermore, we discovered that HISTONE DEACETYLASE 15 (HDA15) interacts with and deacetylates GPX1. HDA15-mediated deacetylation reduced enzymatic activity, nuclear translocation and subsequently the interaction with bZIP68 of GPX1. Accordingly, HDA15-overexpressing rice showed greater membrane damage, weaker induction of bZIP68-regulated genes and increased sensitivity to osmotic stress. These results identify HDA15-mediated GPX1 deacetylation as a negative regulatory mechanism that connects redox enzyme activity, protein localization and stress-responsive transcription in rice.
Fengchao Zhai, Xiaoyun Ma, Wenge Li et al.· International Journal of Mol...· 0 citations