We report on a 6 year old patient with an unusual clinical presentation of WAS and oligoclonal proliferation of TCR+ large granular lymphocytes (LGL). Flow cytometry demonstrated two distinct populations of lymphocytes with strongly decreased (WASP-) or normal expression levels of WASP (WASP+), respectively. Molecular analysis confirmed a splice site mutation in intron 2 of the WASP gene in the...

N-WASP regulates the actin cytoskeleton through activation of the Arp2/3 complex. N-WASP localizes at the cell periphery, where it controls actin polymerization downstream of signal molecules such as adapter proteins, Cdc42, Src family kinases, and phosphoinositides. N-WASP also localizes in the nucleus; however, the role of N-WASP in the nucleus is unclear. Here, we show that localization of N...

Neural Wiskott-Aldrich syndrome protein (N-WASP) regulates reorganization of the actin cytoskeleton through activation of the Arp2/3 complex. Here, we show that heat shock protein 90 (HSP90) regulates N-WASP-induced actin polymerization in cooperation with phosphorylation of N-WASP. HSP90 binds directly to N-WASP, but binding alone does not affect the rate of N-WASP/Arp2/3 complex-induced in vi...

Aims. We present the discovery and characterisation of the exoplanets WASP-113b and WASP-114b by the WASP survey, SOPHIE and CORALIE. Methods. The planetary nature of the systems was established by performing follow-up photometric and spectroscopic observations. The follow-up data were combined with the WASP-photometry and analysed with an MCMC code to obtain system parameters. Results. The hos...

Chemotactic migration of macrophages is critical for the recruitment of leukocytes to inflamed tissues. Macrophages use a specialized adhesive structure called a podosome to migrate. Podosome formation requires the Wiskott-Aldrich syndrome protein (WASP), which is a product of the gene defective in an X-linked inherited immunodeficiency disorder, the Wiskott-Aldrich syndrome. Macrophages from W...

Wiskott-Aldrich syndrome, an inherited blood cell disorder due to mutations of the X-chromosome gene WASP (Wiskott-Aldrich syndrome protein), was characterized originally by thrombocytopenia, immunodeficiency, and eczema. Whereas platelet dysfunction is severe and consistent, immune defects are clinically variable, ranging from negligible to life threatening. To understand this heterogeneity, w...

Although T cell dysfunction and lymphopenia are key features of immunodeficient patients with the Wiskott-Aldrich syndrome and Wiskott-Aldrich syndrome protein (WASP)-deficient mice, T cell development appears relatively normal. We hypothesized that N-WASP, a ubiquitously expressed homologue of WASP, may serve a redundant function with WASP. To examine the unique and redundant activities of WAS...

Arp2/3 complex is believed to induce de novo nucleation of actin filaments at the edge of motile cells downstream of WASp family proteins. In this study, the signaling pathways leading to Arp2/3 complex activation, actin assembly, and shape change were investigated in platelets isolated from patients with Wiskott-Aldrich Syndrome (WAS), that is, who lack WASp, and in WASp-deficient mouse platel...

Wiskott-Aldrich syndrome protein (WASP) plays important roles in TCR signaling. In transgenic (Tg) mice, over-expression of the WASP N-terminal region (exons 1-5) including the enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) homology 1 (EVH1) domain and anti-WASP-EVH1 single-chain variable fragment (scFv) intracellular expressed antibodies (intrabodies) impairs IL-2 production in activ...

Arp2/3 complex is believed to induce de novo nucleation of actin filaments at the edge of motile cells downstream of WASp family proteins. In this study, the signaling pathways leading to Arp2/3 complex activation, actin assembly, and shape change were investigated in platelets isolated from patients with Wiskott-Aldrich Syndrome (WAS), that is, who lack WASp, and in WASp-deficient mouse platel...