WIP Background Information Mutations in the Wiskott-Aldrich syndrome protein (WASP) often result in mmunodeficiency due to abnormal T cell and B cell activation. The 503 amino acid WAS-interacting protein (WIP) contains a number of domains implicated in actin-binding and several putative src homology-binding domains. The first 100 amino acids of WASP interact with amino acids 377-503 of WIP and the majority of pathogenic mutations associated with WAS occur within the first 100 amino acids of WASP. The gene encoding human WIP maps to chromosome 2p23.3-q24.3. Overexpression of WIP in the human B cell line BJAB increases F-actin content and cerebriform projections. While both WIP and Vav cooperate in the regulation of NF-AT/AP-1 gene transcription, the WIP-WASP complex is required for activation of NF-AT/AP-1 necessary for proper T cell function. A dysfunctional WIP-WASP complex may be implicated in the immunodeficient phenotype in WAS.
