Redox regulation of peroxiredoxin and proteinases by ascorbate and thiols during pea root nodule senescence.
Redox factors contributing to nodule senescence were studied in pea. The abundance of the nodule cytosolic peroxiredoxin but not the mitochondrial peroxiredoxin protein was modulated by ascorbate. In contrast to redox-active antioxidants such as ascorbate and cytosolic peroxiredoxin that decreased during nodule development, maximal extractable nodule proteinase activity increased progressively as the nodules aged. Cathepsin-like activities were constant throughout development but serine and cysteine proteinase activities increased during senescence. Senescence-induced cysteine proteinase activity was inhibited by cysteine, dithiotreitol, or E-64. Senescence-dependent decreases in redox-active factors, particularly ascorbate and peroxiredoxin favour decreased redox-mediated inactivation of cysteine proteinases.
Groten
Karin
K
Crop Performance and Improvement Division, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK.
Dutilleul
Christelle
C
van Heerden
Philippus D R
PD
Vanacker
Hélène
H
Bernard
Stéphanie
S
Finkemeier
Iris
I
Dietz
Karl-Josef
KJ
Foyer
Christine H
CH
D000975:Antioxidants / Q000378:metabolism; D001205:Ascorbic Acid / Q000378:metabolism; D002403:Cathepsins / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000378:metabolism; D010084:Oxidation-Reduction; D018532:Pisum sativum / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism*; D010544:Peroxidases / Q000378:metabolism*; D054464:Peroxiredoxins; D018517:Plant Roots / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013997:Time Factors
D000975:Antioxidants; D013438:Sulfhydryl Compounds; D010544:Peroxidases; D054464:Peroxiredoxins; D002403:Cathepsins; D010447:Peptide Hydrolases; D003546:Cysteine Endopeptidases; D001205:Ascorbic Acid