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Updated: Nov 29, 2025
11:56
A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
13.7K
Ascorbate inactivates the oxygen-evolving complex in prolonged darkness.
Anna Podmaniczki1,2, Valéria Nagy1, André Vidal-Meireles1
1Institute of Plant Biology, Biological Research Centre, Szeged, Hungary.
Physiologia Plantarum
|November 20, 2020
Summary
Vitamin C (Ascorbate) plays a role in plant stress. This study shows Ascorbate may negatively impact oxygen-evolving complexes during dark-induced leaf senescence in Arabidopsis.
Area of Science:
- Plant Physiology
- Molecular Biology
- Biochemistry
Background:
- Ascorbate (vitamin C) is crucial for plant development and stress response.
- Dark-induced leaf senescence involves complex physiological changes.
- Oxygen-evolving complexes (OEC) are vital for photosynthesis.
Purpose of the Study:
- To investigate the role of Ascorbate in dark-induced leaf senescence.
- To understand Ascorbate's effect on oxygen-evolving complexes under prolonged darkness.
- To elucidate the mechanisms by which Ascorbate influences OEC inactivation.
Main Methods:
- Arabidopsis thaliana as a model organism.
- Analysis of Ascorbate-deficient (vtc2-4) and OEC subunit mutants (psbo1, psbr).
- Fast chlorophyll a fluorescence and thermoluminescence measurements.
Main Results:
- Ascorbate deficiency attenuated OEC inactivation during dark treatment.
- A psbo1 knockout mutant showed aggravated photosynthetic decline in darkness.
- Ascorbate appears to over-reduce the Mn-complex, leading to OEC inactivation and subunit dissociation.
Conclusions:
- Ascorbate can negatively impact OEC function during prolonged darkness.
- Plant Ascorbate levels and localization are critical for cellular processes.
- This study highlights a novel regulatory role of vitamin C in plant stress response.
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