WIP is a chaperone for Wiskott-Aldrich syndrome protein (WASP).

Wiskott-Aldrich syndrome protein (WASP) is in a complex with WASP-interacting protein (WIP). WASP levels, but not mRNA levels, were severely diminished in T cells from WIP(-/-) mice and were increased by introduction of WIP in these cells. The WASP binding domain of WIP was shown to protect WASP from degradation by calpain in vitro.

WIP and WASP play complementary roles in T cell homing and chemotaxis to SDF-1alpha.

Homing of lymphocytes to tissues is a biologically important multistep process that involves selectin-dependent rolling, integrin-dependent adhesion and chemokine-directed chemotaxis. The actin cytoskeleton plays a central role in lymphocyte adhesion and motility. Wiskott-Aldrich syndrome protein (WASP), the product of the gene mutated in Wiskott-Aldrich syndrome, and its partner, the Wiskott-Aldrich syndrome protein-interacting protein (WIP), play important roles in actin re-organization in T lymphocytes.