meta-Tyrosine induces modification of reactive nitrogen species level, protein nitration and nitrosoglutathione reductase in tomato roots.
A non-protein amino acid (NPAA) - meta-Tyrosine (m-Tyr), is a harmful compound produced by fescue roots. Young (3-4 days old) tomato (Solanum lycopersicum L.) seedlings were supplemented for 24-72 h with m-Tyr (50 or 250 μM) inhibiting root growth by 50 or 100%, without lethal effect. Fluorescence of DAF-FM and APF derivatives was determined to show reactive nitrogen species (RNS) localization and level in roots of tomato plants. m-Tyr-induced restriction of root elongation growth was related to formation of nitrated proteins described as content of 3-nitrotyrosine. Supplementation with m-Tyr enhanced superoxide radicals generation in extracts of tomato roots and stimulated protein nitration. It correlated well to increase of fluorescence of DAF-FM derivatives, and transiently stimulated fluorescence of APF derivatives corresponding respectively to NO and ONOO-formation. Alterations in RNS formation induced by m-Tyr were linked to metabolism of nitrosoglutathione (GSNO). Activity of nitrosoglutatione reductase (GSNOR), catalyzing degradation of GSNO was enhanced by long term plant supplementation with m-Tyr, similarly as protein abundance, while transcripts level were only slightly altered by tested NPAA. We conclude, that although in animal cells m-Tyr is considered as a marker of oxidative stress, its secondary mode of action in tomato plants involves perturbation in RNS formation, alteration in GSNO metabolism and modification of protein nitration level.
Department of Plant Physiology, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland. Electronic address: urszula_krasuska@sggw.pl.
Urszula
U
Krasuska
Department of Plant Physiology, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland. Electronic address: andrzejczakolga5@gmail.com.
Olga
O
Andrzejczak
Department of Plant Physiology, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland. Electronic address: pawel.e.staszek@gmail.com.
Paweł
P
Staszek
Department of Botany, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland. Electronic address: wojciech_borucki@sggw.pl.
Wojciech
W
Borucki
Department of Plant Physiology, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland. Electronic address: agnieszka_gniazdowska@sggw.pl.
Agnieszka
A
Gniazdowska
D000445:Aldehyde Oxidoreductases / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000187:drug effects* / Q000201:enzymology; D018613:Microscopy, Confocal; D009569:Nitric Oxide / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D014443:Tyrosine / Q000737:chemistry / Q000494:pharmacology*
D010940:Plant Proteins; D026361:Reactive Nitrogen Species; D009569:Nitric Oxide; D014443:Tyrosine; C015566:3-tyrosine; D000445:Aldehyde Oxidoreductases; C087006:formaldehyde dehydrogenase, glutathione-independent
GSNOR; Protein nitration; RNS; ROS