Glutathione-mediated reversibility of covalent modification of ubiquitin carboxyl-terminal hydrolase L1 by 1,2-naphthoquinone through Cys152, but not Lys4
• Exposure of SH-SY5Y cells to 1,2-NQ caused covalent modification of UCH-L1. • UCH-L1 undergoes arylation by 1,2-NQ, thereby decreasing its activity. • UCH-L1 Cys152 arylation by 1,2-NQ is reversible via GSH-mediated S-transarylation. • Lys4 modification in UCH-L1 by 1,2-NQ is irreversible by GSH.
