First Author | Nika K | Year | 2006 |
Journal | Mol Cell Biol | Volume | 26 |
Issue | 5 | Pages | 1806-16 |
PubMed ID | 16479000 | Mgi Jnum | J:106911 |
Mgi Id | MGI:3619764 | Doi | 10.1128/MCB.26.5.1806-1816.2006 |
Citation | Nika K, et al. (2006) Lipid raft targeting of hematopoietic protein tyrosine phosphatase by protein kinase C theta-mediated phosphorylation. Mol Cell Biol 26(5):1806-16 |
abstractText | Protein kinase C theta (PKC theta) is unique among PKC isozymes in its translocation to the center of the immune synapse in T cells and its unique downstream signaling. Here we show that the hematopoietic protein tyrosine phosphatase (HePTP) also accumulates in the immune synapse in a PKC theta-dependent manner upon antigen recognition by T cells and is phosphorylated by PKC theta at Ser-225, which is required for lipid raft translocation. Immune synapse translocation was completely absent in antigen-specific T cells from PKC theta-/- mice. In intact T cells, HePTP-S225A enhanced T-cell receptor (TCR)-induced NFAT/AP-1 transactivation, while the acidic substitution mutant was as efficient as wild-type HePTP. We conclude that HePTP is phosphorylated in the immune synapse by PKC theta and thereby targeted to lipid rafts to temper TCR signaling. This represents a novel mechanism for the active immune synapse recruitment and activation of a phosphatase in TCR signaling. |