Premium
Possible target components for the inhibitory effect of N‐ethylmaleimide on the activation of neutrophil NADPH oxidase
Author(s) -
Park JeenWoo,
Park HeeSae,
Lee Su Min
Publication year - 1998
Publication title -
iubmb life
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.132
H-Index - 113
eISSN - 1521-6551
pISSN - 1521-6543
DOI - 10.1080/15216549800203102
Subject(s) - cytosol , nadph oxidase , n ethylmaleimide , chemistry , biochemistry , cell free system , phosphorylation , microbiology and biotechnology , biophysics , enzyme , biology
Potential target components for the inhibitory effect of covalent sulfhydryl‐modifying reagent N‐ethylmaleimide (NEM) on the activation of NADPH oxidase in human neutrophils was studied in a cell‐free system. The capacity of both cytosol and membrane fractions to induce the translocation of cytosolic components and O2‐ generation in the cell‐free activation system was affected by NEM. The phosphorylation of p47phox, which mediates the translocation of cytosolic complex, by protein kinase C was not inhibited by NEM and NEM‐treated p47phox was as effective as untreated p47phox both in the kinase‐dependent and in the amphiphile‐dependent cell‐free activation sysyems. In addition, phosphatidic acid‐dependent phosphorylation of cytosol including p47phox was not affected by NEM. The inhibition of cytosol's capacity to activate NADPH oxidase was partially reversed by an addition of the fraction containing G‐protein rac. Taken together, the data suggest that membrane component cytochrome b558 and cytosolic component rac may be the potential targets for the NEM effect on the activation ofNADPH oxidase.