Linked Life Data

1331759

Source:http://linkedlifedata.com/resource/pubmed/id/1331759

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1992-12-9
pubmed:abstractText
Agonist binding to guanine nucleotide-binding protein (G protein)-coupled receptors in membranes of myeloid differentiated human leukemia (HL-60) cells is inhibited by guanine nucleotides, most potently by the GTP analog guanosine 5'-(gamma-thio)triphosphate (GTP gamma S). In order to study whether GTP gamma S formed locally from adenosine 5'-(gamma-thio)triphosphate (ATP gamma S) and GDP by nucleoside diphosphokinase has any advantage over exogenously added GTP gamma S in binding to and activating G proteins, regulation of complement component 5a (C5a) binding to its receptors, as well as formation of GTP gamma S, was studied in membranes of HL-60 cells. GTP gamma S added to HL-60 membranes potently inhibited binding of 125I-C5a (IC50 about 3 nM), an effect not influenced by addition of either GDP or ATP gamma S. When HL-60 membranes were incubated with the combination of ATP gamma S and GDP, a marked potentiation (up to 300-fold) of the inhibition caused by either GDP or ATP gamma S alone was observed. By measuring nucleoside diphosphokinase-catalyzed formation of GTP gamma S and inhibition of 125I-C5a binding in the presence of GDP and ATP gamma S under identical assay conditions, it was found that formed GTP gamma S inhibited binding of 125I-C5a with an IC50 value of about 0.3 nM, thus being about 10-fold more potent than exogenously added GTP gamma S. These data suggest that the GTP gamma S-forming nucleoside diphosphokinase is closely associated with the C5a receptor-G protein complex and channels the formed GTP gamma S into the G protein.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
731-5
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Evidence for nucleoside diphosphokinase-dependent channeling of guanosine 5'-(gamma-thio)triphosphate to guanine nucleotide-binding proteins.
pubmed:affiliation
Institut für Pharmakologie, Universität GH Essen, FRG.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't