Molecular and genetic insights into T cell antigen receptor signal transduction

The T cell response to antigen is initiated by the TCR through its ability to regulate the phosphorylation of tyrosine residues of critical intracellular molecules. The TCR uses a modular system in which sequence motifs, ARAMs, within the ζ and CD3 chains to communicate with intracellular PTKs. These PTK interact with the TCR in a sequential and coordinated manner. This rather complex modular system may have evolved to insure that all requirement of the signalling mechanism are met before a response is initiated. Mistakes could result in autoimmunity. It is likely that the general features of this system will reflect the events involved in B cell antigen receptor and IgE Fc receptor signal transduction since ARAMs as well as Src and Syk/ZAP-70 family members are used in these systems as well.