The Wiskott-Aldrich syndrome: disordered actin dynamics in haematopoietic cells

The Wiskott-Aldrich syndrome protein (WASp) is a member of a unique family whose members share similar domain structures and are responsible for the t ransduction of signals from the cell membrane to the actin cytoskeleton. Fo r WASp, the interactions with Rho family GTPases and the cytoskeletal organ ising complex Arp2/3 are critical to these functions, which when disturbed translate into abnormalities of haematopoietic cell signaling, polarisation , migration and phagocytosis. This review discusses the evidence for regula tion of highly dynamic cytoskeletal structures by WASp and the consequences of disturbed function on some of these processes.