Redox regulation of NADP-malate dehydrogenase is vital for land plants under fluctuating light environment
Open Access
- 2 February 2021
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 118 (6)
- https://doi.org/10.1073/pnas.2016903118
Abstract
Many enzymes involved in photosynthesis possess highly conserved cysteine residues that serve as redox switches in chloroplasts. These redox switches function to activate or deactivate enzymes during light-dark transitions and have the function of fine-tuning their activities according to the intensity of light. Accordingly, many studies on chloroplast redox regulation have been conducted under the hypothesis that “fine regulation of the activities of these enzymes is crucial for efficient photosynthesis.” However, the impact of the regulatory system on plant metabolism is still unclear. To test this hypothesis, we here studied the impact of the ablation of a redox switch in chloroplast NADP-malate dehydrogenase (MDH). By genome editing, we generated a mutant plant whose MDH lacks one of its redox switches and is active even in dark conditions. Although NADPH consumption by MDH in the dark is expected to be harmful to plant growth, the mutant line did not show any phenotypic differences under standard long-day conditions. In contrast, the mutant line showed severe growth retardation under short-day or fluctuating light conditions. These results indicate that thiol-switch redox regulation of MDH activity is crucial for maintaining NADPH homeostasis in chloroplasts under these conditions.Keywords
Funding Information
- MEXT | Japan Society for the Promotion of Science (16H06556)
- MEXT | Japan Society for the Promotion of Science (19H03241)
- Deutsche Forschungsgemeinschaft (390686111)
This publication has 68 references indexed in Scilit:
- Redox regulation of the Calvin–Benson cycle: something old, something newFrontiers in Plant Science, 2013
- Overexpression of chloroplast NADPH-dependent thioredoxin reductase in Arabidopsis enhances leaf growth and elucidates in vivo function of reductase and thioredoxin domainsFrontiers in Plant Science, 2013
- Multiple strategies to prevent oxidative stress in Arabidopsis plants lacking the malate valve enzyme NADP-malate dehydrogenaseJournal of Experimental Botany, 2011
- Single Cystathionine β-Synthase Domain–Containing Proteins Modulate Development by Regulating the Thioredoxin System in ArabidopsisTHE PLANT CELL ONLINE, 2011
- Effects of AOX1a Deficiency on Plant Growth, Gene Expression of Respiratory Components and Metabolic Profile Under Low-Nitrogen Stress in Arabidopsis thalianaPlant and Cell Physiology, 2010
- Production and Scavenging of Reactive Oxygen Species in Chloroplasts and Their FunctionsPlant Physiology, 2006
- Determination of the Regulatory Disulfide Bonds of NADP-Dependent Malate Dehydrogenase from Pisum sativum by Site-Directed MutagenesisBiological Chemistry, 1997
- Direct evidence for the different roles of the N‐ and C‐terminal regulatory disulfides of sorghum leaf NADP‐malate dehydrogenase in its activation by reduced thioredoxinFEBS Letters, 1996
- A thioredoxin‐independent fully active NADP‐malate dehydrogenase obtained by site‐directed mutagenesisFEBS Letters, 1993
- Role of Light in the Regulation of Chloroplast EnzymesAnnual Review of Plant Physiology, 1980