The Thioredoxin-Regulated α-Amylase 3 of Arabidopsis thaliana Is a Target of S-Glutathionylation
| العنوان: | The Thioredoxin-Regulated α-Amylase 3 of Arabidopsis thaliana Is a Target of S-Glutathionylation |
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| المؤلفون: | Francesca Sparla, Diana Santelia, Libero Gurrieri, Luca Distefano, Nicolas Rouhier, Claudia Pirone, Mirko Zaffagnini, Paolo Trost, Daniel Horrer, David Seung |
| المساهمون: | Gurrieri L., Distefano L., Pirone C., Horrer D., Seung D., Zaffagnini M., Rouhier N., Trost P., Santelia D., Sparla F., Università di Bologna [Bologna] (UNIBO), University of Zürich [Zürich] (UZH), Swiss Fed Inst Technol, John Innes Centre, Interactions Arbres-Microorganismes (IAM), Université de Lorraine (UL)-Institut National de la Recherche Agronomique (INRA), Swiss National Science Foundation (SNSF) 31003A_166539 Department of Pharmacy and Biotechnology, University of Bologna, Programma Marco Polo short term fellowship 1883, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Universität Zürich [Zürich] = University of Zurich (UZH), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Santelia, Diana |
| المصدر: | Frontiers in Plant Science, 10 Frontiers in Plant Science Frontiers in Plant Science, Frontiers, 2019, 10, ⟨10.3389/fpls.2019.00993⟩ Frontiers in Plant Science, Vol 10 (2019) Frontiers in Plant Science (10), . (2019) |
| بيانات النشر: | Frontiers Media SA, 2019. |
| سنة النشر: | 2019 |
| مصطلحات موضوعية: | 0106 biological sciences, 0301 basic medicine, REDOX REGULATION, STRESS, [SDV]Life Sciences [q-bio], S-glutathionylation, PROTEIN, STARCH DEGRADATION, Plant Science, lcsh:Plant culture, GLUTAREDOXIN S12, medicine.disease_cause, 01 natural sciences, Redox, GUARD-CELL METABOLISM, MECHANISMS, post-translational redox modifications, 03 medical and health sciences, chemistry.chemical_compound, TRANSITORY STARCH, BREAKDOWN, ASCORBATE, Glutaredoxin, medicine, oxidative stress, lcsh:SB1-1110, S-Glutathionylation, α-amylase 3, Post-translational redox modifications, Disulfide, Cysteine pKa, Thioredoxin, chemistry.chemical_classification, Reactive oxygen species, arabidopsis thaliana, stress oxydatif, glutaredoxin, thioredoxin, Glutathione, 030104 developmental biology, chemistry, Biochemistry, post-translational redox modification, cysteine pKa, glutathionylation, régulation redox, Oxidative stress, disulfide, 010606 plant biology & botany, Cysteine |
| الوصف: | Reactive oxygen species (ROS) are produced in cells as normal cellular metabolic by-products. ROS concentration is normally low, but it increases under stress conditions. To stand ROS exposure, organisms evolved series of responsive mechanisms. One such mechanism is protein S-glutathionylation. S-glutathionylation is a post-translational modification typically occurring in response to oxidative stress, in which a glutathione reacts with cysteinyl residues, protecting them from overoxidation. α-Amylases are glucan hydrolases that cleave α-1,4-glucosidic bonds in starch. The Arabidopsis genome contains three genes encoding α-amylases. The sole chloroplastic member, AtAMY3, is involved in osmotic stress response and stomatal opening and is redox-regulated by thioredoxins. Here we show that AtAMY3 activity was sensitive to ROS, such as H2O2. Treatments with H2O2 inhibited enzyme activity and part of the inhibition was irreversible. However, in the presence of glutathione this irreversible inhibition was prevented through S-glutathionylation. The activity of oxidized AtAMY3 was completely restored by simultaneous reduction by both glutaredoxin (specific for the removal of glutathione-mixed disulfide) and thioredoxin (specific for the reduction of protein disulfide), supporting a possible liaison between both redox modifications. By comparing free cysteine residues between reduced and GSSG-treated AtAMY3 and performing oxidation experiments of Cys-to-Ser variants of AtAMY3 using biotin-conjugated GSSG, we could demonstrate that at least three distinct cysteinyl residues can be oxidized/glutathionylated, among those the two previously identified catalytic cysteines, Cys499 and Cys587. Measuring the pKa values of the catalytic cysteines by alkylation at different pHs and enzyme activity measurement (pKa1 = 5.70 ± 0.28; pKa2 = 7.83 ± 0.12) showed the tendency of one of the two catalytic cysteines to deprotonation, even at physiological pHs, supporting its propensity to undergo redox post-translational modifications. Taking into account previous and present findings, a functional model for redox regulation of AtAMY3 is proposed. Frontiers in Plant Science, 10 ISSN:1664-462X |
| وصف الملف: | application/application/pdf; ELETTRONICO; application/pdf |
| تدمد: | 1664-462X |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f5e8903a402aaaaedd531660ce5e1d57 https://doi.org/10.3389/fpls.2019.00993 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....f5e8903a402aaaaedd531660ce5e1d57 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 1664462X |
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