Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-2-11
pubmed:abstractText
Priming of polymorphonuclear leukocyte responses to chemoattractants by TNF plays an important role in host defenses and inflammatory responses. TNF-induced priming is associated with an 80% increase in the membrane density of G alpha(i2) protein that is coupled to chemoattractant receptors. The present study examines the hypothesis that TNF stimulates increased synthesis of alpha(i2). Within 10 min of addition, TNF stimulated a significant increase in total cellular G alpha(i2), as determined by pertussis toxin-catalyzed ADP ribosylation, which was blocked by the translation inhibitor cycloheximide. Immunoprecipitation of biosynthetically labeled alpha(i2) showed that TNF increased alpha(i2) synthesis by about 20% at 10 min. Nuclear run-ons showed no change in alpha(i2) mRNA synthesis in TNF-treated cells; however, steady state alpha(i2) mRNA levels were reduced following a 10-min exposure to TNF. Pretreatment with cycloheximide prevented the TNF-induced reduction in steady state alpha(i2) mRNA levels. Therefore, TNF stimulates alpha(i2) protein synthesis and mRNA degradation in the same time frame as priming. The increased alpha(i2) synthesis results from increased translation, not transcription, of alpha(i2) mRNA. Simultaneous G alpha(i2) protein synthesis and mRNA degradation provide a mechanism by which TNF priming is associated with a rapid, self-limiting increase in G protein expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
158
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
913-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
TNF translationally modulates the expression of G1 protein alpha(i2) subunits in human polymorphonuclear leukocytes.
pubmed:affiliation
Department of Medicine, University of Louisville Health Sciences Center, Veterans' Affairs Medical Center, KY 40206, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't