EVIDENCE THAT THE WISKOTT-ALDRICH SYNDROME PROTEIN MAY BE INVOLVED INLYMPHOID-CELL SIGNALING PATHWAYS

Wiskott-Aldrich syndrome is an X-linked combined immunodeficiency affe cting cells of several different hemopoietic lineages, The Wiskott-Ald rich syndrome protein (WASP), which has no homology with any other kno wn protein families, is rich in proline motifs known to contribute to Src homology 3 binding sites. However, its function has not been deter mined, The Tec family of cytoplasmic tyrosine kinases, which include B tk (the X-linked agammaglobulinemia gene), Itk, and Tec, is thought to be involved in lymphoid cell signaling pathways, In this work, we sho w binding of WASP to the Src homology 3 domains of Btk, Itk, Tee, Grb2 , and phospholipase C-gamma, which suggests a function for WASP in lym phoid cell signaling.