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Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells
The T cell surface molecule CD28 can provide costimulatory signals that permit the full activation of T cells. Here we demonstrate that stimulation of CD28, either by B7, its natural ligand, or by the anti- CD28 monoclonal antibody 9.3, induces an association between CD28 and phosphatidylinositol 3-...
Formato: | Texto |
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Lenguaje: | English |
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The Rockefeller University Press
1994
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2191424/ https://www.ncbi.nlm.nih.gov/pubmed/7509360 |
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collection | PubMed |
description | The T cell surface molecule CD28 can provide costimulatory signals that permit the full activation of T cells. Here we demonstrate that stimulation of CD28, either by B7, its natural ligand, or by the anti- CD28 monoclonal antibody 9.3, induces an association between CD28 and phosphatidylinositol 3-kinase (PI3-K) in Jurkat T cells, raising the possibility that an interaction with PI3-K contributes to CD28-mediated signaling. To examine the mechanism of the association, we synthesized tyrosine-phosphorylated oligopeptides corresponding to each of the four tyrosines in the CD28 cytoplasmic domain. When added to lysates of B7- stimulated Jurkat cells, the oligopeptide corresponding to Tyr 173 inhibits the coimmunoprecipitation of PI3-K with CD28; the other oligopeptides have no effect. Tyr 173 is contained within the sequence YMNM, a motif that is also found in the platelet-derived growth factor receptor and that, when phosphorylated, forms a high affinity binding site for the p85 subunit of PI3-K. These observations suggest that phosphorylation of Tyr 173 may mediate the interaction between CD28 and PI3-K. However, because CD28 is not known to be phosphorylated, it remains possible that CD28 interacts with PI3-K through a mechanism independent of tyrosine phosphorylation. |
format | Text |
id | pubmed-2191424 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1994 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21914242008-04-16 Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells J Exp Med Articles The T cell surface molecule CD28 can provide costimulatory signals that permit the full activation of T cells. Here we demonstrate that stimulation of CD28, either by B7, its natural ligand, or by the anti- CD28 monoclonal antibody 9.3, induces an association between CD28 and phosphatidylinositol 3-kinase (PI3-K) in Jurkat T cells, raising the possibility that an interaction with PI3-K contributes to CD28-mediated signaling. To examine the mechanism of the association, we synthesized tyrosine-phosphorylated oligopeptides corresponding to each of the four tyrosines in the CD28 cytoplasmic domain. When added to lysates of B7- stimulated Jurkat cells, the oligopeptide corresponding to Tyr 173 inhibits the coimmunoprecipitation of PI3-K with CD28; the other oligopeptides have no effect. Tyr 173 is contained within the sequence YMNM, a motif that is also found in the platelet-derived growth factor receptor and that, when phosphorylated, forms a high affinity binding site for the p85 subunit of PI3-K. These observations suggest that phosphorylation of Tyr 173 may mediate the interaction between CD28 and PI3-K. However, because CD28 is not known to be phosphorylated, it remains possible that CD28 interacts with PI3-K through a mechanism independent of tyrosine phosphorylation. The Rockefeller University Press 1994-03-01 /pmc/articles/PMC2191424/ /pubmed/7509360 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Articles Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells |
title | Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells |
title_full | Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells |
title_fullStr | Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells |
title_full_unstemmed | Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells |
title_short | Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells |
title_sort | stimulation of cd28 triggers an association between cd28 and phosphatidylinositol 3-kinase in jurkat t cells |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2191424/ https://www.ncbi.nlm.nih.gov/pubmed/7509360 |