Protein tyrosine nitration in pea roots during development and senescence.
Protein tyrosine nitration is a post-translational modification mediated by reactive nitrogen species (RNS) that is associated with nitro-oxidative damage. No information about this process is available in relation to higher plants during development and senescence. Using pea plants at different developmental stages (ranging from 8 to 71 days), tyrosine nitration in the main organs (roots, stems, leaves, flowers, and fruits) was analysed using immunological and proteomic approaches. In the roots of 71-day-old senescent plants, nitroproteome analysis enabled the identification a total of 16 nitrotyrosine-immunopositive proteins. Among the proteins identified, NADP-isocitrate dehydrogenase (ICDH), an enzyme involved in the carbon and nitrogen metabolism, redox regulation, and responses to oxidative stress, was selected to evaluate the effect of nitration. NADP-ICDH activity fell by 75% during senescence. Analysis showed that peroxynitrite inhibits recombinant cytosolic NADP-ICDH activity through a process of nitration. Of the 12 tyrosines present in this enzyme, mass spectrometric analysis of nitrated recombinant cytosolic NADP-ICDH enabled this study to identify the Tyr392 as exclusively nitrated by peroxynitrite. The data as a whole reveal that protein tyrosine nitration is a nitric oxide-derived PTM prevalent throughout root development and intensifies during senescence.
Department of Biochemistry, Molecular and Cellular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain.
Juan C
JC
Begara-Morales
Mounira
M
Chaki
Beatriz
B
Sánchez-Calvo
Capilla
C
Mata-Pérez
Marina
M
Leterrier
José M
JM
Palma
Juan B
JB
Barroso
Francisco J
FJ
Corpas
D016923:Cell Death; D003600:Cytosol / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D057075:Enzyme Assays; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism; D018613:Microscopy, Confocal; D009569:Nitric Oxide / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D018532:Pisum sativum / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D030421:Peroxynitrous Acid / Q000378:metabolism; D018517:Plant Roots / Q000201:enzymology / Q000378:metabolism*; D018547:Plant Stems / Q000201:enzymology / Q000378:metabolism; D020543:Proteome / Q000032:analysis / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors; D014443:Tyrosine / Q000378:metabolism*
D007527:Isoenzymes; D020543:Proteome; D030421:Peroxynitrous Acid; D009569:Nitric Oxide; D014443:Tyrosine; D007521:Isocitrate Dehydrogenase; C039355:isocitrate dehydrogenase (NADP+); D013482:Superoxide Dismutase