Genetic Engineering with Tropical Fern Enzyme Improves Stress Tolerance, Yield, and Quality of Crops
Overexpression of glutaredoxin in crop plants appears to improve stress tolerance and reduce yield loss due to abiotic stress factors such as drought and high temperature. Drought and temperature extremes can severely limit plant growth and crop productivity, an increasingly important issue as global warming leads to more adverse climate events. Across the United States in 2014, eight weather and climate disasters exceeded $1 billion in costs per event. Little progress has been made in breeding stress-tolerant plants due to the complex nature of plant metabolic adaptations to drought and high temperature stress. Researchers at the University of Florida have developed genetically engineered plants with an enzyme from the tropical fern Pteris vittata. This enzyme functions at high temperatures and efficiently reduces damage produced by reactive oxygen species that result from abiotic stress, and as a result plants expressing this enzyme suffer less yield loss under adverse conditions.
Genetically engineered crop plants with increased resistance to heat stress and other abiotic stressors
- Provides some protection against abiotic stressors such as drought, and heat , increasing stress tolerance in crops and decreasing agricultural losses
- Potentially maintains farm profitability in era of increasingly limited, more costly water supplies and rising global temperatures
High temperatures and drought result in the production of reactive oxygen species, causing injury to plants by oxidative stress. Oxidative stress is combated by glutaredoxins, which are enzymes within plants that protect specific proteins. Because of possible connections between glutaredoxins and abiotic stress tolerance, University of Florida researchers evaluated the high temperature stress tolerance of transgenic plants expressing an enzyme in the tropical fern Pteris vittata, PvGrx5. PvGrx5 is a novel glutaredoxin and plays a role in whole-plant thermotolerance. By protecting certain proteins from oxidative damage via glutaredoxin expression, researchers were able to alter the function of several proteins allowing for heat tolerance in plants. Arabidopsis and rice plants expressing the PvGrx5 displayed improved tolerance to high temperature stress. This study provides the first evidence for the role of a glutaredoxin in high temperature stress tolerance in plants.