Linked Life Data

10893420

Source:http://linkedlifedata.com/resource/pubmed/id/10893420

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
37
pubmed:dateCreated
2000-10-13
pubmed:abstractText
Human neutrophils participate in the host innate immune response, partly mediated by the multicomponent superoxide-generating enzyme NADPH oxidase. A correlation between phosphorylation of cytosolic NADPH oxidase components and enzyme activation has been identified but is not well understood. We previously showed that p22(phox), the small subunit of the membrane-bound oxidase component flavocytochrome b(558), is an in vitro substrate for both a phosphatidic acid-activated kinase and conventional protein kinase C isoforms (Regier, D. S., Waite, K. A., Wallin, R., and McPhail, L. C. (1999) J. Biol. Chem. 274, 36601-36608). Here we show that several neutrophil agonists (phorbol myristate acetate, opsonized zymosan, and N-formyl-methionyl-leucyl-phenylalanine) induce p22(phox) phosphorylation in intact neutrophils. To determine if phospholipase D (PLD) is needed for p22(phox) phosphorylation, cells were pretreated with ethanol, which reduces phosphatidic acid production by PLD in stimulated cells. Phorbol myristate acetate-induced phosphorylation of p22(phox) and NADPH oxidase activity were not reduced by ethanol. In contrast, ethanol reduced both activities when cells were stimulated by N-formyl-methionyl-leucyl-phenylalanine or opsonized zymosan. Varying the time of stimulation with opsonized zymosan showed that the phosphorylation of p22(phox) coincides with NADPH oxidase activation. GF109203X, an inhibitor of protein kinase C and the phosphatidic acid-activated protein kinase, decreased both p22(phox) phosphorylation and NADPH oxidase activity in parallel in opsonized zymosan-stimulated cells. Stimulus-induced phosphorylation of p22(phox) was on Thr residue(s), in agreement with in vitro results. Overall, these data show that NADPH oxidase activity and p22(phox) phosphorylation are correlated and suggest two mechanisms (PLD-dependent and -independent) by which p22(phox) phosphorylation occurs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
28406-12
pubmed:dateRevised
2010-12-3
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Phosphorylation of p22phox is mediated by phospholipase D-dependent and -independent mechanisms. Correlation of NADPH oxidase activity and p22phox phosphorylation.
pubmed:affiliation
Departments of Biochemistry and Medicine, Division of Infectious Diseases, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't