Waltzing with WASP

Wiskott-Aldrich syndrome (WAS) is an inherited immune deficiency that is ma rked by eczema, bleeding and recurrent infections. The lymphocytes and plat elets of WAS patients display cytoskeletal abnormalities, and their T lymph ocytes show a diminished proliferative response to stimulation through the T-cell receptor-CD3 complex (TCR-CD3). The product of the WAS gene, WAS pro tein (WASP), binds to the small GTPase Cdc42. Small GTPases of the Rho fami ly are crucial for the regulation of the actin-based cytoskeleton. WASP and its relative NWASP might play an important role in regulating the actin cy toskeleton. Since both WASP and NWASP have the potential to bind to multipl e proteins, they might serve as a hub to coordinate the redistribution of m any cellular signals to the actin cytoskeleton. In this review, the authors discuss the possible role of WASP/NWASP and of the newly described protein WIP, which interacts with WASP and NWASP, in coupling signals from the T-c ell receptor to the actin-based cytoskeleton.