Neural Wiskott-Aldrich syndrome protein, WASL, WASP
Members of the Wiskott-Aldrich sydrome protein (WASP) family regulate the formation of actin-based cell structures in many cell types. These proteins contain C-terminal actin-binding domains that can stimulate actin polymerization. WASP is expressed primarily in hematopoietic cells, while its homolog N-WASP is widely expressed. These proteins have 48% identity in human with higher homology in the functional regions of these proteins. Phosphorylation at serine and tyrosine residues regulates the activity of both proteins. WASP is tyrosine phosphorylated at tyrosine 291 after antigen receptor activation in B-cells and collagen stimulation of platelets. Phosphorylation of the analogous site in N-WASP (Tyr-256) stimulates its activity, reduces nuclear N-WASP, and is required for neurite extension.
