T cell antigen-receptor signal transduction

During the past year, major progress has been made in understanding proxima l TCR signal-transduction events. Cbl has been identified as a negative reg ulator of kinases from the ZAP-70/Syk family. Studies on. LAT, SLP-76, Itk and Vav have revealed their role in the activation of Ras and phospholipase -C gamma 1-Ca2+ signalling pathways, TCR-induced cytoskeletal changes invol ve signalling through SLP-76-Vav-Nck to activate effecters of the Rho-famil y of GTPases. Finally, glycolipid-enriched microdomains play a crucial role in T cell activation.