Involvement of non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase in response to oxidative stress

• Published in: Journal of plant physiology Vol. 165; no. 4; pp. 456 - 461
• Main Authors: Bustos, Diego M., Bustamante, Claudia A., Iglesias, Alberto A.
• Format: Journal Article
• Language: English
• Published: Jena Elsevier GmbH 13.03.2008; Elsevier
• Subjects: Biological and medical sciences; Enzyme Stability - drug effects; Enzymes; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Enzymologic - drug effects; Gene Expression Regulation, Plant - drug effects; Glyceraldehyde-3-Phosphate Dehydrogenases - genetics; Glyceraldehyde-3-Phosphate Dehydrogenases - metabolism; Hydrogen Peroxide - pharmacology; Metabolism; NP-Ga3PDHase activity; Oxidants - pharmacology; Oxidative stress; Oxidative Stress - drug effects; Paraquat - pharmacology; Phosphorylation - drug effects; Plant physiology and development; Protein stability; RNA, Messenger - genetics; RNA, Messenger - metabolism; Seedlings - drug effects; Seedlings - enzymology; Triticum - drug effects; Triticum - enzymology; Triticum - genetics; Zea mays - drug effects; Zea mays - enzymology; Zea mays - genetics; Oxidative stress; NP-Ga3PDHase activity; Protein stability
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2007.06.005

Glyceraldehyde-3-phosphate dehydrogenases catalyze key steps in energy and reducing power partitioning in cells of higher plants. Because non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase (NP-Ga3PDHase) is involved in the production of reductive power (NADPH) in the cytosol, its behavior under oxidative stress conditions was analyzed. The specific activity of the enzyme was found to increase up to 2-fold after oxidative conditions imposed by methylviologen in wheat and maize seedlings. Under moderate oxidant concentration, lack of mRNA induction was observed. The increase in specific activity would thus be a consequence of a significant stability of NP-Ga3PDHase. Our results suggest that the enzyme could be modified by oxidation of cysteine residues, but formation of disulfide bridges is dependent on levels of divalent cations and 14-3-3 proteins. The latter differential effect could be critical to relatively maintain energy and reductant levels in the cytoplasm of plant cells under oxidative stress.