Back to Search
Start Over
Reduction of oxalate levels in tomato fruit and consequent metabolic remodeling following overexpression of a fungal oxalate decarboxylase.
- Source :
-
Plant physiology [Plant Physiol] 2013 May; Vol. 162 (1), pp. 364-78. Date of Electronic Publication: 2013 Mar 12. - Publication Year :
- 2013
-
Abstract
- The plant metabolite oxalic acid is increasingly recognized as a food toxin with negative effects on human nutrition. Decarboxylative degradation of oxalic acid is catalyzed, in a substrate-specific reaction, by oxalate decarboxylase (OXDC), forming formic acid and carbon dioxide. Attempts to date to reduce oxalic acid levels and to understand the biological significance of OXDC in crop plants have met with little success. To investigate the role of OXDC and the metabolic consequences of oxalate down-regulation in a heterotrophic, oxalic acid-accumulating fruit, we generated transgenic tomato (Solanum lycopersicum) plants expressing an OXDC (FvOXDC) from the fungus Flammulina velutipes specifically in the fruit. These E8.2-OXDC fruit showed up to a 90% reduction in oxalate content, which correlated with concomitant increases in calcium, iron, and citrate. Expression of OXDC affected neither carbon dioxide assimilation rates nor resulted in any detectable morphological differences in the transgenic plants. Comparative proteomic analysis suggested that metabolic remodeling was associated with the decrease in oxalate content in transgenic fruit. Examination of the E8.2-OXDC fruit proteome revealed that OXDC-responsive proteins involved in metabolism and stress responses represented the most substantially up- and down-regulated categories, respectively, in the transgenic fruit, compared with those of wild-type plants. Collectively, our study provides insights into OXDC-regulated metabolic networks and may provide a widely applicable strategy for enhancing crop nutritional value.
- Subjects :
- Carboxy-Lyases metabolism
Down-Regulation
Flammulina enzymology
Fruit genetics
Fruit metabolism
Fungal Proteins genetics
Fungal Proteins metabolism
Gene Expression
Solanum lycopersicum genetics
Solanum lycopersicum growth & development
Organ Specificity
Plant Proteins genetics
Plant Proteins metabolism
Plants, Genetically Modified
Proteomics
Carboxy-Lyases genetics
Flammulina genetics
Solanum lycopersicum metabolism
Plant Proteins isolation & purification
Signal Transduction
Subjects
Details
- Language :
- English
- ISSN :
- 1532-2548
- Volume :
- 162
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- Plant physiology
- Publication Type :
- Academic Journal
- Accession number :
- 23482874
- Full Text :
- https://doi.org/10.1104/pp.112.209197