Linked Life Data

9973466

Source:http://linkedlifedata.com/resource/pubmed/id/9973466

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-4-13
pubmed:abstractText
The cytoplasmic domain of CD28 contains four tyrosine residues. Because signal transduction by CD28 appears to involve its tyrosine phosphorylation, we determined sites of CD28 tyrosine phosphorylation using mutants of mouse CD28 that retained tyrosine at one position, with the remaining three positions mutated to phenylalanine. When expressed in Jurkat cells and stimulated by mAb, only the mutants with tyrosine at position 170 or 188 were tyrosine phosphorylated. Phosphorylation of Tyr170 recruits phosphatidylinositol 3-kinase to CD28. Tyr188 has not been associated with any specific signaling event, but we found that ligation of CD28 by the natural ligand B7.2 also induced phosphorylation of Tyr188, suggesting that this event is of physiological importance. Consistent with that possibility, mutation of Tyr188 to phenylalanine severely impaired the ability of mouse CD28 to deliver a costimulus for the expression of CD69 and the production of IL-2. The functional consequences of the mutation of Tyr188 were unique; mutation of the other three tyrosines, individually or in combination, did not impair costimulation. Therefore, of the four CD28 tyrosine residues only Tyr188 is required for signaling in Jurkat cells, suggesting that its phosphorylation is a key event in the costimulation of T cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
162
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1966-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Identification of tyrosine phosphorylation sites in the CD28 cytoplasmic domain and their role in the costimulation of Jurkat T cells.
pubmed:affiliation
Department of Medicine, Rosalind Russell Research Laboratory, San Francisco General Hospital, University of California 94143, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't