Linked Life Data

1707924

Source:http://linkedlifedata.com/resource/pubmed/id/1707924

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1991-5-23
pubmed:abstractText
The T cell Ag (Ti-CD3) receptor complex has been proposed to regulate phosphoinositide-specific phospholipase C (PLC) through a cholera toxin (CTX)-sensitive guanine nucleotide-binding (G) protein. In this study, we have used CTX and staurosporine as pharmacologic probes to further define the linkage between the Ti-CD3 receptor and PLC activity in the human T cell line, Jurkat. CTX pretreatment inhibited Ti-CD3 receptor-dependent phosphoinositide hydrolysis and, concomitantly, protein tyrosine kinase activation in intact cells. Studies with electrically permeabilized Jurkat cells revealed that guanosine 5'-(3-O-thio) triphosphate stimulated an increase in PLC activity, that unlike the response to Ti-CD3 receptor ligation, was not affected by cellular pretreatment with CTX. In contrast, the phosphotyrosine phosphatase inhibitors, orthovanadate and molybdate anions, stimulated phosphoinositide hydrolysis in permeabilized cells through a CTX-sensitive mechanism of PLC activation. Additional studies with a known PTK inhibitor, staurosporine, supported the results obtained with CTX. Staurosporine pretreatment inhibited the phosphoinositide hydrolysis induced by anti-CD3 antibodies or phosphotyrosine phosphatase inhibitors, but failed to alter the G protein-dependent PLC activation response to guanosine 5'-(3-O-thio) triphosphate. The results of this study indicate that PLC activity(s) in Jurkat cells are regulated by both G protein- and PTK-dependent coupling mechanisms. However, the differential inhibitory effects of CTX and staurosporine on these PLC activation pathways strongly suggest that a protein tyrosine kinase activation event, rather than a G protein, mediates the functional linkage between the Ti-CD3 receptor and PLC activity in Jurkat cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Alkaloids, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Cholera Toxin, http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Lymphocyte Specific Protein..., http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositols, http://linkedlifedata.com/resource/pubmed/chemical/Phosphoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Phosphotyrosine, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Antigen, T-Cell, http://linkedlifedata.com/resource/pubmed/chemical/Staurosporine, http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases, http://linkedlifedata.com/resource/pubmed/chemical/Tyrosine
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
146
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2889-97
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Signal transduction through the T cell antigen receptor. Activation of phospholipase C through a G protein-independent coupling mechanism.
pubmed:affiliation
Department of Immunology, Mayo Clinic, Rochester, MN 55905.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.