WAS Gene

The WAS gene (WASP stands for "Wiskott-Aldrich Syndrome Protein) is a protein-coding gene located on chromosome Xp11.23. WASP is an effector protein for Rho-type GTPases that regulates actin filament reorganization via its interaction with the Arp2/3 complex. It is important for efficient actin polymerization. The WAS protein is a possible regulator of lymphocyte and platelet function. It mediates actin filament reorganization and actin pedestal formation upon infection with pathogenic bacteria. In addition to its role in the cytoplasmic cytoskeleton, it also promotes actin polymerization in the nucleus, thereby regulating gene transcription and repair of damaged DNA. Furthermore, the encoded protein promotes repair by homologous recombination (HR) in response to DNA damage by promoting actin polymerization in the nucleus.

The Wiskott-Aldrich syndrome (WAS) family proteins share a similar domain structure and are involved in relaying signals from cell surface receptors to the actin cytoskeleton. The presence of a number of different motifs suggests that they are regulated by a number of different stimuli and interact with multiple proteins. Recent studies have shown that these proteins are directly or indirectly associated with the small GTPase Cdc42, which is known to regulate actin filament formation, and the cytoskeleton organizing complex Arp2/3.

X-linked recessive mutations in the WAS gene are associated with Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome is based on a rare is characterized by dysregulation of the immune system and microthrombocytopenia. The WAS gene product is a cytoplasmic protein expressed exclusively in hematopoietic cells that exhibit signaling and cytoskeletal abnormalities in WAS patients. A transcript variant has been described that arises from alternative use of the promoter and contains a different 5'-UTR sequence, but the full length of this sequence is not known.

Related signaling pathways include regulation of actin dynamics for phagocytic cup formation and remodeling of the cytoskeleton Regulation of the actin cytoskeleton by Rho GTPases.

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