Adaptor proteins in lymphocyte activation.

Adaptor proteins are unique, as they contain modular domains and lack intrinsic enzymatic activity. These proteins are scaffolds for the organization of macromolecular complexes and they recruit other proteins for correct localization during molecular signal transduction. Numerous recent advances have been made through the elucidation of new adaptor proteins and the recognition of novel functions for previously identified molecules. In addition, the roles of adaptors in both the positive and negative regulation of lymphocyte activation have been further clarified.