Carbonylation of the cytoskeletal protein actin leads to aggregate formation.
Protein carbonylation is a common feature in cells exposed to oxidants, leading to protein dysfunction and protein aggregates. Actin, which is involved in manifold cellular processes, is a sensitive target protein to this oxidative modification. T-cell proteins have been widely described to be sensitive targets to oxidative modifications. The aim of this work was to test whether the formation of protein aggregates contributes to the impaired proliferation of Jurkat cells after oxidative stress and to test whether actin as a major oxidation-prone cytoskeletal protein is an integral part of such protein aggregates. We used Jurkat cells, an established T-cell model, showing the formation of actin aggregates along with the decrease of proteasome activity. The presence of these protein aggregates inhibits Jurkat proliferation even under conditions not influencing viability. As a conclusion, we propose that an oxidative environment leads to actin aggregates contributing to T-cell cellular functional impairment.
Departamento de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, 4200-319, Portugal.
Jose Pedro
JP
Castro
Christiane
C
Ott
Tobias
T
Jung
Tilman
T
Grune
Henrique
H
Almeida
D000199:Actins / Q000378:metabolism*; D059447:Cell Cycle Checkpoints; D049109:Cell Proliferation; D002470:Cell Survival; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D019169:Jurkat Cells; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D050050:Protein Carbonylation; D055550:Protein Stability; D021381:Protein Transport; D013601:T-Lymphocytes / Q000378:metabolism / Q000502:physiology
D000199:Actins; D016877:Oxidants; D006861:Hydrogen Peroxide; D046988:Proteasome Endopeptidase Complex