Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 2 de 2
Filter
Add more filters











Database
Type of study
Language
Publication year range
1.
Antioxidants (Basel) ; 9(5)2020 May 16.
Article in English | MEDLINE | ID: mdl-32429369

ABSTRACT

Dehydroascorbate reductases (DHARs) are important enzymes that reconvert the dehydroascorbic acid (DHA) into ascorbic acid (ASC). They are involved in the plant response to oxidative stress, such as that induced by the mycotoxin beauvericin (BEA). Tomato plants were treated with 50 µM of BEA; the main antioxidant compounds and enzymes were evaluated. DHARs were analyzed in the presence of different electron donors by native and denaturing electrophoresis as well as by western blot and mass spectrometry to identify a novel induced protein with DHAR activity. Kinetic parameters for dehydroascorbate (DHA) and glutathione (GSH) were also determined. The novel DHAR was induced after BEA treatment. It was GSH-dependent and possessed lower affinity to DHA and GSH than the classical DHARs. Interestingly, the mass spectrometry analysis of the main band appearing on sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) revealed a chloroplast sedoheptulose 1,7-bisphosphatase, a key enzyme of the Calvin cycle, and a chloroplast mRNA-binding protein, suggesting that the DHA reducing capacity could be a side activity or the novel DHAR could be part of a protein complex. These results shed new light on the ascorbate-glutathione regulation network under oxidative stress and may represent a new way to increase the plant antioxidant defense system, plant nutraceutical value, and the health benefits of plant consumption.

2.
J Plant Physiol ; 200: 53-61, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-27340858

ABSTRACT

Fusarium verticillioides is a fungal pathogen of maize that causes ear rot and contaminates the grains with fumonisin mycotoxins. Breeding for resistance to Fusarium emerged as the most economic and environmentally safe strategy; therefore the discovery of resistant sources and effective molecular markers are a priority. Ears of resistant (CO441 and CO433) and susceptible (CO354 and CO389) maize lines were inoculated with F. verticillioides and the expression of pathogenesis-related (PR) genes (PR1, PR5, PRm3, PRm6) and genes that protect from oxidative stress (peroxidase, catalase, superoxide dismutase and ascorbate peroxidase) were evaluated in the kernels at 72h post inoculation. In addition, the oxidation level and the enzymatic activity of ascorbate-glutathione cycle, catalase, superoxide dismutase and cytosolic and wall peroxidases were investigated. The uninoculated kernels of the resistant lines showed higher gene expression and enzymatic activities, highlighting the key role of constitutive resistance in limiting pathogen attack. In contrast, the susceptible lines activated defensive genes only after pathogen inoculation, resulting in increased levels of H2O2 and lipid peroxidation, as well as lower enzymatic activities. The constitutive defenses observed in this study from seed could be profitably exploited to develop markers to speed up conventional breeding programs in the selection of resistant genotypes.


Subject(s)
Antioxidants/metabolism , Disease Resistance , Fusarium/physiology , Plant Diseases/immunology , Plant Diseases/microbiology , Plant Proteins/metabolism , Zea mays/enzymology , Zea mays/microbiology , Disease Resistance/genetics , Fusarium/growth & development , Gene Dosage , Gene Expression Profiling , Gene Expression Regulation, Plant , Genes, Plant , Genotype , Hydrogen Peroxide/metabolism , Malondialdehyde/metabolism , Oxidative Stress/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Zea mays/genetics , Zea mays/immunology
SELECTION OF CITATIONS
SEARCH DETAIL