English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/190170
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


2-Cys peroxiredoxins participate in the oxidation of chloroplast enzymes in the dark

AuthorsOjeda, Valle; Pérez-Ruiz, Juan Manuel ; Cejudo, Francisco Javier
Enzyme oxidation
Hydrogen peroxide
Issue Date5-Nov-2018
CitationMolecular Plant 11(11): 1377-1388 (2018)
AbstractMost redox-regulated chloroplast enzymes are reduced during the day and oxidized during the night. While the reduction mechanism of light-dependent enzymes is well known, the mechanism mediating their oxidation in the dark remains unknown. The thiol-dependent peroxidases, 2-Cys peroxiredoxins (Prxs), play a key role in light-dependent reduction of chloroplast enzymes. Prxs transfer reducing equivalents of thiols to hydrogen peroxide, suggesting the participation of these peroxidases in enzyme oxidation in the dark. Here, we have addressed this issue by analyzing the redox state of well-known redox-regulated chloroplast enzymes in response to darkness in Arabidopsis thaliana mutants deficient in chloroplast-localized Prxs (2-Cys Prxs A and B, Prx IIE, and Prx Q). Mutant plants lacking 2-Cys Prxs A and B, and plants overexpressing NADPH-dependent thioredoxin (Trx) reductase C showed delayed oxidation of chloroplast enzymes in the dark. In contrast, the deficiencies of Prx IIE or Prx Q exerted no effect. In vitro assays allowed the reconstitution of the pathway of reducing equivalents from reduced fructose 1,6-bisphosphatase to hydrogen peroxide mediated by Trxs and 2-Cys Prxs. Taken together, these results suggest that 2-Cys Prxs participate in the short-term oxidation of chloroplast enzymes in the dark. Chloroplast biosynthetic enzymes that are reduced in the light become rapidly oxidized in the dark. Here, we show that enzyme oxidation occurs by the transfer of thiol-reducing equivalents via Trxs and 2-Cys Prxs, but not Prx Q nor Prx IIE, to hydrogen peroxide, which thus acts as the final sink for reducing power from stromal enzymes.
Publisher version (URL)https://doi.org/10.1016/j.molp.2018.09.005
Appears in Collections:(IBVF) Artículos
Files in This Item:
File Description SizeFormat 
2-Cys_peroxiredoxins_participate_oxidation_chloroplast_enzymes_dark.pdf1,39 MBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.