Open AccessThe immediate activator of the NADPH oxidase is arachidonate not phosphorylation
Author(s) -
HENDERSON Lydia M.,
MOULE S. Kelly,
CHAPPELL J. Brian
Publication year - 1993
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1993.tb19882.x
Subject(s) - nadph oxidase , superoxide , staurosporine , phosphorylation , protein kinase c , chemistry , activator (genetics) , protein phosphorylation , protein kinase a , biochemistry , microbiology and biotechnology , signal transduction , oxidase test , kinase , phospholipase a2 , phorbol , biology , enzyme , receptor
Superoxide generation is rapidly triggered following the addition of a stimulus to neutrophils. The signal‐transduction pathway culminates in the activation of protein kinase C, whose phosphorylation of a protein component is considered to activate the oxidase. Arachidonate stimulated the oxidase in a concentration‐dependent manner but, unlike phorbol‐12‐myristate‐13‐acetate (PMA), was not inhibited by staurosporine, a protein kinase inhibitor. Increase protein phosphorylation, apparent with PMA, was not observed when superoxide generation was triggered by arachidonate. Inhibitors of phospholipase A 2 inhibit the PMA activation of the oxidase. Therefore, we propose that arachidonate and not phosphorylation is the immediate stimulus for superoxide generation.