| First Author | Kao H | Year | 2008 |
| Journal | J Immunol | Volume | 181 |
| Issue | 12 | Pages | 8248-57 |
| PubMed ID | 19050241 | Mgi Jnum | J:142079 |
| Mgi Id | MGI:3820367 | Doi | 10.4049/jimmunol.181.12.8248 |
| Citation | Kao H, et al. (2008) Regulated movement of CD4 in and out of the immunological synapse. J Immunol 181(12):8248-57 |
| abstractText | The mechanism underlying the transient accumulation of CD4 at the immunological synapse (IS) and its significance for T cell activation are not understood. To investigate these issues, we mutated a serine phosphorylation site (S408) in the cytoplasmic tail of murine CD4. Preventing phosphorylation of S408 did not block CD4 recruitment to the IS; rather, it blocked the ability of CD4 to leave the IS. Surprisingly, enhanced and prolonged CD4 accumulation at the supramolecular activation cluster in the contact area had no functional consequence for T cell activation, cytokine production, or proliferation. Protein kinase C theta (PKCtheta)-deficient T cells also displayed enhanced and prolonged accumulation of wild-type CD4 at the IS, indicating that theta is the critical PKC isoform involved in CD4 movement. These findings suggest a model wherein recruitment of CD4 to the IS allows its phosphorylation by PKCtheta and subsequent removal from the IS. Thus, an important role for PKCtheta in T cell activation involves its recruitment to the IS, where it phosphorylates specific substrates that help to maintain the dynamism of protein turnover at the IS. |
