S-Nitrosation of Arabidopsis thaliana Protein Tyrosine Phosphatase 1 Prevents Its Irreversible Oxidation by Hydrogen Peroxide

Abstract

Tyrosine-specific protein tyrosine phosphatases (Tyr-specific PTPases) are key signaling enzymes catalyzing the removal of the phosphate group from phosphorylated tyrosine residues on target proteins. This post-translational modification notably allows the regulation of mitogen-activated protein kinase (MAPK) cascades during defense reactions. Arabidopsis thaliana protein tyrosine phosphatase 1 (AtPTP1), the only Tyr-specific PTPase present in this plant, acts as a repressor of H2O2 production and regulates the activity of MPK3/MPK6 MAPKs by direct dephosphorylation. Here, we report that recombinant histidine (His)-AtPTP1 protein activity is directly inhibited by H2O2 and nitric oxide (NO) exogenous treatments. The effects of NO are exerted by S-nitrosation, i.e., the formation of a covalent bond between NO and a reduced cysteine residue. This post-translational modification targets the catalytic cysteine C265 and could protect the AtPTP1 protein from its irreversible oxidation by H2O2. This mechanism of protection could be a conserved mechanism in plant PTPases.

MAPK activity and MAP kinase phosphatase 2 (AtMKP2) protein stability under altered glutathione homeostasis inArabidopsis thaliana

“…The highly conserved catalytic domain suggests, that such modifications may take place in plant proteins as well, but they have not been described for the subfamily of plant dual specificity MAPK phosphatases yet (Bheri et al, 2021). However, Arabidopsis thaliana protein tyrosine phosphatase 1 (AtPTP1), the only Tyr-specific PTPase present in this plant was shown to be directly inhibited by H 2 O 2 and can be protected by S-nitrosation on its catalytic cysteine (Nicolas-Francès et al, 2022). Even though MKP2 seems to be a rather long-lived protein, our experiments show, that the severe stress does impact MKP2 stability, and replacement of catalytic cysteine with serine residue causes even more pronounced degradation.…”

H2O2, NO, and H2S networks during root development and signalling under physiological and challenging environments: Beneficial or toxic?

“…An example is the S-nitrosothiol thionitrous acid (HSNO) as cellular redox regulation, which is generated by the interaction between NO and H 2 S (Antoniou et al, 2020;Kashfi et al, 2015;Marcolongo et al, 2019). Insights into the nature of the interaction between NO and ROS have been critically analyzed by several researchers in the recent past (Del Castello et al, 2019;Groß et al, 2013;Nicolas-Francès et al, 2022;Scheler et al, 2013). NO-ROS interactions might exhibit synergistic and antagonistic interactions in plant metabolic pathways and physiological responses (Del Castello et al, 2019, Innocenti et al, 2007, Zhou et al, 2005.…”

“…H 2 O 2 acts as a local and long-distance-systemic signalling molecule in plant organs occurring in the range of 50-5.000 nM g −1 FW (Fichman & Mittler, 2020;Fraudentali et al, 2020;Niu & Liao, 2016;Zhu et al, 2015). The direct interaction of NO and NO-derived molecules can mediate protein posttranslational modifications (PTMs), mainly S-nitrosation and tyrosine nitration, and modulate key enzymes of the ROS metabolism (Begara-Morales et al, 2013a, 2013bChaki et al, 2015;Gupta et al, 2020;Kohli et al, 2019;Palma et al, 2020).…”

“…This finding was accompanied by the lower APX activity, modulating H 2 O 2 homoeostasis in rice roots. NO and H 2 O 2 are known to be generated under similar situations of stressful environments where the formation of both biomolecules share similar kinetics (Niu & Liao, 2016). Oxalate oxidase analysis in maize plants performed through EM-imaging and enzyme staining demonstrated that apoplastic H 2 O 2 production regulates cell division and primary root elongation in the apical root growth zone of maize plants raised under normal and water stress conditions (Voothuluru and Sharp, 2013;Voothuluru et al, 2020).…”

Redox post-translational modifications and their interplay in plant abiotic stress tolerance

“…PTP1 presents a Cys catalytic residue, Cys265, whose irreversible overoxidation induced by H 2 O 2 inhibits its activity. However, Cys265 may suffer S-nitrosylation, induced by NO·, in a mechanism by which it protects the catalytic residue from overoxidation and consequent enzymatic inactivation ( Nicolas-Francès et al., 2022 ).…”