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Updated: May 12, 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
Regulation of ascorbic acid synthesis in plants
Juan Wang1, Zhijin Zhang, Rongfeng Huang
1Biotechnology Research Institute; Chinese Academy of Agricultural Sciences; Beijing, PR China.
Plant Signaling & Behavior
|April 23, 2013
Summary
Ascorbic acid (AsA) synthesis in plants is regulated at multiple levels. Key enzymes like VTC1 are controlled by transcription factors and protein degradation, impacting plant growth and stress response.
Area of Science:
- Plant Biochemistry
- Molecular Biology
- Plant Physiology
Background:
- Ascorbic acid (AsA) is a vital antioxidant crucial for plant growth and development.
- Understanding the regulation of AsA synthesis and metabolism is essential but remains incomplete.
- AsA levels are influenced by both de novo synthesis and recycling of its oxidized form.
Purpose of the Study:
- To elucidate the regulatory mechanisms governing AsA synthesis and metabolism in Arabidopsis.
- To integrate existing knowledge with recent findings on transcriptional and post-transcriptional regulation of AsA pathways.
Main Methods:
- Review of existing literature and recent experimental evidence.
- Analysis of transcriptional regulation by Arabidopsis ERF98 on VTC1 gene expression.
- Investigation of post-transcriptional regulation involving COP9 signalosome (CSN) subunit CSN5B and VTC1 interaction.
Main Results:
- Ascorbic acid synthesis is modulated by both transcriptional and post-transcriptional controls in Arabidopsis.
- Arabidopsis ERF98 activates VTC1 gene expression, enhancing AsA content and salt stress response.
- CSN5B interacts with VTC1, promoting its degradation in the dark to regulate diurnal AsA level changes.
Conclusions:
- Plant ascorbic acid synthesis is finely tuned through complex regulatory networks.
- Transcriptional activation and protein degradation represent key mechanisms controlling AsA biosynthesis.
- Further research into these regulatory pathways will enhance our understanding of plant antioxidant systems.
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