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Glycolysis dominates over photorespiration in governing oxalate accumulation in rice.
Wei Yu1, Peixin Yuan1, Guanling Li1
1Guangdong Provincial Key Laboratory for the Development Biology and Environmental Adaptation of Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China.
Plant Physiology
|June 12, 2026
Summary
Plant oxalate accumulation is driven by glycolysis, not photorespiration. Nitrate and nitrite reduction, along with specific organic acids, influence oxalate levels in rice, with NAD/NADH playing a regulatory role.
Area of Science:
- Plant biochemistry
- Metabolic regulation
- Molecular genetics
Background:
- Oxalate is a key plant metabolite with diverse functions.
- Its biosynthesis and regulation in plants are not fully understood.
Purpose of the Study:
- To elucidate the mechanisms of oxalate accumulation in rice.
- To investigate the roles of nitrate/nitrite reduction and glycolysis in oxalate synthesis.
Main Methods:
- Utilized CRISPR-Cas9 gene editing to create rice mutants for nitrate reductase (NR) and nitrite reductase (NiR).
- Performed various chemical treatments, transcriptomic, and metabolomic analyses.
- Investigated the effects of glycolytic intermediates and inhibitors.
Main Results:
- NR and NiR mutants showed significantly reduced oxalate levels, restored by nitrite and nitrate respectively.
- Glycolysis intermediates and inhibitors confirmed glycolysis drives oxalate synthesis.
- Oxalate levels correlated positively with glycolytic and TCA cycle gene expression and metabolites.
Conclusions:
- Oxalate accumulation in rice is closely linked to glycolysis.
- Nitrate and nitrite reduction, but not ammonium assimilation, modulate oxalate levels.
- Photorespiration indirectly impacts oxalate accumulation via glycerate and glycolysis.
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