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Updated: Jun 13, 2026
11:56
A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
The signal network of ascorbate homeostasis
1Institute of Plant Biology, National Taiwan University; Taipei, Taiwan.
Plant Signaling & Behavior
|May 4, 2010
Summary
Methanol stimulates ascorbate production in plants by activating antioxidant pathways. This study proposes a model for how methanol and other apoplastic factors maintain ascorbate homeostasis during plant cell growth.
Area of Science:
- Plant physiology
- Biochemistry
- Cellular signaling
Background:
- Ascorbate (vitamin C) is a vital antioxidant, protecting plant cells from oxidative stress.
- Factors influencing ascorbate levels are known, but methanol's role is less understood.
- Methanol, a pectin byproduct, upregulates ascorbate biosynthesis genes via Smirnoff-Wheeler and galacturonate pathways.
Purpose of the Study:
- To elucidate the signaling network regulating ascorbate homeostasis in plants.
- To investigate the role of methanol and apoplastic factors in ascorbate regulation.
- To propose a working model for methanol-induced ascorbate signaling.
Main Methods:
- Analysis of gene expression related to ascorbate biosynthesis.
- Investigating the role of hydrogen peroxide as a secondary messenger.
- Modeling the signaling network involving apoplastic factors like methanol and oligogalacturonide.
Main Results:
- Methanol enhances ascorbate-biosynthetic gene expression.
- Hydrogen peroxide, a product of methanol detoxification, activates ascorbate-related genes.
- A signaling network model is proposed linking methanol, oligogalacturonide, and ascorbate homeostasis.
Conclusions:
- Methanol acts as a signaling molecule influencing ascorbate levels in plants.
- Hydrogen peroxide mediates methanol's effect on ascorbate gene expression.
- The proposed model provides insights into plant cell response to apoplastic factors.
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