Wounding induces a peroxisomal <scp>H<sub>2</sub>O<sub>2</sub></scp> decrease via glycolate oxidase‐catalase switch dependent on glutamate receptor‐like channel‐supported Ca<sup>2+</sup> signaling in plants
Xiangyang Li, Linru Chen, Xiaoyue Zeng, Kaixin Wu, Jiayu Huang, Mengmeng Liao, Yue Xi, Guohui Zhu, Xiuying Zeng, Xuewen Hou, Zhisheng Zhang, Xinxiang Peng
Abstract
SUMMARY Sensing of environmental challenges, such as mechanical injury, by a single plant tissue results in the activation of systemic signaling, which attunes the plant's physiology and morphology for better survival and reproduction. As key signals, both calcium ions (Ca 2+ ) and hydrogen peroxide (H 2 O 2 ) interplay with each other to mediate plant systemic signaling. However, the mechanisms underlying Ca 2+ ‐H 2 O 2 crosstalk are not fully revealed. Our previous study showed that the interaction between glycolate oxidase and catalase, key enzymes of photorespiration, serves as a molecular switch (GC switch) to dynamically modulate photorespiratory H 2 O 2 fluctuations via metabolic channeling. In this study, we further demonstrate that local wounding induces a rapid shift of the GC switch to a more interactive state in systemic leaves, resulting in a sharp decrease in peroxisomal H 2 O 2 levels, in contrast to a simultaneous outburst of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase‐derived apoplastic H 2 O 2 . Moreover, the systemic response of the two processes depends on the transmission of Ca 2+ signaling, mediated by glutamate‐receptor‐like Ca 2+ channels 3.3 and 3.6. Mechanistically, by direct binding and/or indirect mediation by some potential biochemical sensors, peroxisomal Ca 2+ regulates the GC switch states in situ , leading to changes in H 2 O 2 levels. Our findings provide new insights into the functions of photorespiratory H 2 O 2 in plant systemic acclimation and an optimized systemic H 2 O 2 signaling via spatiotemporal interplay between the GC switch and NADPH oxidases.