1-s2.0-S2213231721002652-main.pdf 2,28MB
1000 Titel
  • Decreased proteasomal cleavage at nitrotyrosine sites in proteins and peptides
1000 Autor/in
  1. Ott, Christiane |
  2. Tomasina, Florencia |
  3. Campolo, Nicolas |
  4. Bartesaghi, Silvana |
  5. Mastrogiovanni, Mauricio |
  6. Leyva, Alejandro |
  7. Batthyány, Carlos |
  8. Meinl, Walter |
  9. Grune, Tilman |
  10. Radi, Rafael |
1000 Erscheinungsjahr 2021
1000 LeibnizOpen
1000 Publikationstyp
  1. Artikel |
1000 Online veröffentlicht
  • 2021-08-18
1000 Erschienen in
1000 Quellenangabe
  • 46:102106
1000 FRL-Sammlung
1000 Copyrightjahr
  • 2021
1000 Lizenz
1000 Verlagsversion
  • |
  • |
1000 Ergänzendes Material
  • |
1000 Publikationsstatus
1000 Begutachtungsstatus
1000 Sprache der Publikation
1000 Abstract/Summary
  • Removal of moderately oxidized proteins is mainly carried out by the proteasome, while highly modified proteins are no longer degradable. However, in the case of proteins modified by nitration of tyrosine residues to 3-nitrotyrosine (NO2Y), the role of the proteasome remains to be established. For this purpose, degradation assays and mass spectrometry analyses were performed using isolated proteasome and purified fractions of native cytochrome c (Cyt c) and tyrosine nitrated proteoforms (NO2Y74-Cyt c and NO2Y97-Cyt c). While Cyt c treated under mild conditions with hydrogen peroxide was preferentially degraded by the proteasome, NO2Y74- and NO2Y97-Cyt c species did not show an increased degradation rate with respect to native Cyt c. Peptide mapping analysis confirmed a decreased chymotrypsin-like cleavage at C-terminal of NO2Y sites within the protein, with respect to unmodified Y residues. Additionally, studies with the proteasome substrate suc-LLVY-AMC (Y-AMC) and its NO2Y-containing analog, suc-LLVNO2Y-AMC (NO2Y-AMC) were performed, both using isolated 20S-proteasome and astrocytoma cell lysates as the proteasomal source. Comparisons of both substrates showed a significantly decreased proteasome activity towards NO2Y-AMC. Moreover, NO2Y-AMC, but not Y-AMC degradation rates, were largely diminished by increasing the reaction pH, suggesting an inhibitory influence of the additional negative charge contained in NO2Y-AMC secondary to nitration. The mechanism of slowing of proteasome activity in NO2Y-contaning peptides was further substantiated in studies using the phenylalanine and nitro-phenylalanine peptide analog substrates. Finally, degradation rates of Y-AMC and NO2Y-AMC with proteinase K were the same, demonstrating the selective inability of the proteasome to readily cleave at nitrotyrosine sites. Altogether, data indicate that the proteasome has a decreased capability to cleave at C-terminal of NO2Y residues in proteins with respect to the unmodified residues, making this a possible factor that decreases the turnover of oxidized proteins, if they are not unfolded, and facilitating the accumulation of nitrated proteins.
1000 Sacherschließung
lokal Nitrotyrosine
lokal Peroxynitrite
lokal Protein oxidation
lokal Cytochrome c
lokal Proteasome activity
1000 Fächerklassifikation (DDC)
1000 Liste der Beteiligten
1000 Label
1000 Fördernummer
  1. -
1000 Förderprogramm
  1. -
1000 Dateien
  1. Decreased proteasomal cleavage at nitrotyrosine sites in proteins and peptides
1000 Objektart article
1000 Beschrieben durch
1000 @id frl:6432540.rdf
1000 Erstellt am 2022-03-28T09:44:11.983+0200
1000 Erstellt von 317
1000 beschreibt frl:6432540
1000 Bearbeitet von 317
1000 Zuletzt bearbeitet Wed Jul 27 07:16:10 CEST 2022
1000 Objekt bearb. Wed Jul 27 07:16:10 CEST 2022
1000 Vgl. frl:6432540
1000 Oai Id
  1. |
1000 Sichtbarkeit Metadaten public
1000 Sichtbarkeit Daten public
1000 Gegenstand von

View source