The Experts below are selected from a list of 3168 Experts worldwide ranked by ideXlab platform
Tadaomi Takenawa - One of the best experts on this subject based on the ideXlab platform.
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actin dynamics regulated by the balance of neuronal wiskott aldrich Syndrome Protein n wasp and cofilin activities determines the biphasic response of glucose induced insulin secretion
Journal of Biological Chemistry, 2013Co-Authors: Eita Uenishi, Tadaomi Takenawa, Tadao Shibasaki, Harumi Takahashi, Chihiro Seki, Hitomi Hamaguchi, Takao Yasuda, Masato Tatebe, Yutaka Oiso, Susumu SeinoAbstract:Actin dynamics in pancreatic β-cells is involved in insulin secretion. However, the molecular mechanisms of the regulation of actin dynamics by intracellular signals in pancreatic β-cells and its role in phasic insulin secretion are largely unknown. In this study, we elucidate the regulation of actin dynamics by neuronal Wiskott-Aldrich Syndrome Protein (N-WASP) and cofilin in pancreatic β-cells and demonstrate its role in glucose-induced insulin secretion (GIIS). N-WASP, which promotes actin polymerization through activation of the actin nucleation factor Arp2/3 complex, was found to be activated by glucose stimulation in insulin-secreting clonal pancreatic β-cells (MIN6-K8 β-cells). Introduction of a dominant-negative mutant of N-WASP, which lacks G-actin and Arp2/3 complex-binding region VCA, into MIN6-K8 β-cells or knockdown of N-WASP suppressed GIIS, especially the second phase. We also found that cofilin, which severs F-actin in its dephosphorylated (active) form, is converted to the phosphorylated (inactive) form by glucose stimulation in MIN6-K8 β-cells, thereby promoting F-actin remodeling. In addition, the dominant-negative mutant of cofilin, which inhibits activation of endogenous cofilin, or knockdown of cofilin reduced the second phase of GIIS. However, the first phase of GIIS occurs in the G-actin predominant state, in which cofilin activity predominates over N-WASP activity. Thus, actin dynamics regulated by the balance of N-WASP and cofilin activities determines the biphasic response of GIIS.
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the wasp wave Protein network connecting the membrane to the cytoskeleton
Nature Reviews Molecular Cell Biology, 2007Co-Authors: Tadaomi Takenawa, Shiro SuetsuguAbstract:Membrane-binding and membrane-deforming Proteins have emerged as binding partners of the Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins that regulate the actin cytoskeleton. Membrane deformation and cytoskeletal reorganization might be coupled in processes that require alteration of membrane shapes, including endocytosis and membrane protrusion. Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins are scaffolds that link upstream signals to the activation of the ARP2/3 complex, leading to a burst of actin polymerization. ARP2/3-complex-mediated actin polymerization is crucial for the reorganization of the actin cytoskeleton at the cell cortex for processes such as cell movement, vesicular trafficking and pathogen infection. Large families of membrane-binding Proteins were recently found to interact with WASP and WAVE family Proteins, therefore providing a new layer of membrane-dependent regulation of actin polymerization.
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the wasp wave Protein network connecting the membrane to the cytoskeleton
Nature Reviews Molecular Cell Biology, 2007Co-Authors: Tadaomi Takenawa, Shiro SuetsuguAbstract:Membrane-binding and membrane-deforming Proteins have emerged as binding partners of the Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins that regulate the actin cytoskeleton. Membrane deformation and cytoskeletal reorganization might be coupled in processes that require alteration of membrane shapes, including endocytosis and membrane protrusion. Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins are scaffolds that link upstream signals to the activation of the ARP2/3 complex, leading to a burst of actin polymerization. ARP2/3-complex-mediated actin polymerization is crucial for the reorganization of the actin cytoskeleton at the cell cortex for processes such as cell movement, vesicular trafficking and pathogen infection. Large families of membrane-binding Proteins were recently found to interact with WASP and WAVE family Proteins, therefore providing a new layer of membrane-dependent regulation of actin polymerization.
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neural wiskott aldrich Syndrome Protein is recruited to rafts and associates with endophilin a in response to epidermal growth factor
Journal of Biological Chemistry, 2003Co-Authors: Makiko Otsuki, Toshiki Itoh, Tadaomi TakenawaAbstract:Neural Wiskott-Aldrich Syndrome Protein (N-WASP) has been implicated in endocytosis; however, little is known about how it interacts functionally with the endocytic machinery. Sucrose gradient fractionation experiments and immunofluorescence studies with anti-N-WASP antibody revealed that N-WASP is recruited together with clathrin and dynamin, which play essential roles in clathrin-mediated endocytosis, to lipid rafts in an epidermal growth factor (EGF)-dependent manner. Endophilin A (EA) binds to dynamin and plays an essential role in the fission step of clathrin-mediated endocytosis. In the present study, we show that the Src homology 3 (SH3) domain of EA associates with the proline-rich domain of N-WASP and dynamin in vitro. Co-immunoprecipitation assays with anti-N-WASP antibody revealed that EGF induces association of N-WASP with EA. In addition, EA enhances N-WASP-induced actin-related Protein 2/3 (Arp2/3) complex activation in vitro. Immunofluorescence studies revealed that actin accumulates at sites where N-WASP and EA are co-localized after EGF stimulation. Furthermore, studies of overexpression of the SH3 domain of EA indicate that EA may regulate EGF-induced recruitment of N-WASP to lipid rafts. These results suggest that, upon EGF stimulation, N-WASP interacts with EA through its proline-rich domain to induce the fission step of clathrin-mediated endocytosis.
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essential role of neural wiskott aldrich Syndrome Protein in podosome formation and degradation of extracellular matrix in src transformed fibroblasts
Cancer Research, 2002Co-Authors: Kiyohito Mizutani, Hiroaki Miki, Hiroshi Maruta, Tadaomi TakenawaAbstract:Transformation of cells by the src oncogene causes dramatic changes in adhesive structures. In v-src-transformed 3Y1 rat fibroblasts (3Y1-src), there are actin-rich protrusive structures called podosomes by which attachment to the extracellular matrix is thought to occur. In this study, we found that neural Wiskott-Aldrich Syndrome Protein (N-WASP) colocalizes with filamentous actin (F-actin) in podosomes. Expression of dominant-negative mutants of N-WASP, Deltacof N-WASP and DeltaVPH N-WASP, both of which are incapable of activating the Arp2/3 complex, suppressed podosome formation, suggesting that N-WASP is essential in this process. Localization of N-WASP in podosomes appears to be attributable to interaction between N-WASP and the SH3 domain of cortactin. Indeed, microinjection of the cortactin SH3 domain suppressed podosome formation. We also observed that 3Y1-src cells cultured on fibronectin degrade the fibronectin primarily at the podosomes and that the inhibition of podosome formation by Deltacof N-WASP abolishes the fibronectin degradation. These results suggest the importance of N-WASP in podosome formation and extracellular matrix degradation, which are processes thought to underlie the invasive phenotype of 3Y1-src cells.
Daniel D Billadeau - One of the best experts on this subject based on the ideXlab platform.
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dedicator of cytokinesis 8 interacts with talin and wiskott aldrich Syndrome Protein to regulate nk cell cytotoxicity
Journal of Immunology, 2013Co-Authors: Hyoungjun Ham, Sabrice Guerrier, Jung Jin Kim, Renee A Schoon, Erik L Anderson, Michael J Hamann, Zhenkun Lou, Daniel D BilladeauAbstract:Recently, patients with mutations in DOCK8 have been reported to have a combined immunodeficiency characterized by cutaneous viral infections and allergies. NK cells represent a first-line defense against viral infections, suggesting that DOCK8 might participate in NK cell function. In this study, we demonstrate that DOCK8-suppressed human NK cells showed defects in natural cytotoxicity as well as specific activating receptor-mediated NK cytotoxicity. Additionally, compared with control NK cells, NK cells depleted of DOCK8 showed defective conjugate formation, along with decreased polarization of LFA-1, F-actin, and cytolytic granules toward the cytotoxic synapse. Using a proteomic approach, we found that DOCK8 exists in a macromolecular complex with the Wiskott-Aldrich Syndrome Protein, an actin nucleation-promoting factor activated by CDC42, as well as talin, which is required for integrin-mediated adhesion. Taken together, our results demonstrate an important role for DOCK8 in NK cell effector function and provide important new mechanistic insight into how DOCK8 regulates F-actin and integrin-mediated adhesion in immune cells.
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hematopoietic lineage cell specific Protein 1 functions in concert with the wiskott aldrich Syndrome Protein to promote podosome array organization and chemotaxis in dendritic cells
Journal of Immunology, 2011Co-Authors: Deborah Klos A Dehring, Daniel D Billadeau, Fiona Clarke, Brendon G Ricart, Yanping Huang, Timothy S Gomez, Edward K Williamson, Daniel A Hammer, Yair Argon, Janis K BurkhardtAbstract:Dendritic cells (DCs) are professional APCs that reside in peripheral tissues and survey the body for pathogens. Upon activation by inflammatory signals, DCs undergo a maturation process and migrate to lymphoid organs, where they present pathogen-derived Ags to T cells. DC migration depends on tight regulation of the actin cytoskeleton to permit rapid adaptation to environmental cues. We investigated the role of hematopoietic lineage cell-specific Protein 1 (HS1), the hematopoietic homolog of cortactin, in regulating the actin cytoskeleton of murine DCs. HS1 localized to lamellipodial protrusions and podosomes, actin-rich structures associated with adhesion and migration. DCs from HS1(-/-) mice showed aberrant lamellipodial dynamics. Moreover, although these cells formed recognizable podosomes, their podosome arrays were loosely packed and improperly localized within the cell. HS1 interacts with Wiskott-Aldrich Syndrome Protein (WASp), another key actin-regulatory Protein, through mutual binding to WASp-interacting Protein. Comparative analysis of DCs deficient for HS1, WASp or both Proteins revealed unique roles for these Proteins in regulating podosomes with WASp being essential for podosome formation and with HS1 ensuring efficient array organization. WASp recruitment to podosome cores was independent of HS1, whereas HS1 recruitment required Src homology 3 domain-dependent interactions with the WASp/WASp-interacting Protein heterodimer. In migration assays, the phenotypes of HS1- and WASp-deficient DCs were related, but distinct. WASp(-/y) DCs migrating in a chemokine gradient showed a large decrease in velocity and diminished directional persistence. In contrast, HS1(-/-) DCs migrated faster than wild-type cells, but directional persistence was significantly reduced. These studies show that HS1 functions in concert with WASp to fine-tune DC cytoarchitecture and direct cell migration.
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wash and wave actin regulators of the wiskott aldrich Syndrome Protein wasp family are controlled by analogous structurally related complexes
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Timothy S Gomez, Michael K Rosen, Zoltan Metlagel, Junko Umetani, Zbyszek Otwinowski, Daniel D BilladeauAbstract:We recently showed that the Wiskott–Aldrich Syndrome Protein (WASP) family member, WASH, localizes to endosomal subdomains and regulates endocytic vesicle scission in an Arp2/3-dependent manner. Mechanisms regulating WASH activity are unknown. Here we show that WASH functions in cells within a 500 kDa core complex containing Strumpellin, FAM21, KIAA1033 (SWIP), and CCDC53. Although recombinant WASH is constitutively active toward the Arp2/3 complex, the reconstituted core assembly is inhibited, suggesting that it functions in cells to regulate actin dynamics through WASH. FAM21 interacts directly with CAPZ and inhibits its actin-capping activity. Four of the five core components show distant (approximately 15% amino acid sequence identify) but significant structural homology to components of a complex that negatively regulates the WASP family member, WAVE. Moreover, biochemical and electron microscopic analyses show that the WASH and WAVE complexes are structurally similar. Thus, these two distantly related WASP family members are controlled by analogous structurally related mechanisms. Strumpellin is mutated in the human disease hereditary spastic paraplegia, and its link to WASH suggests that misregulation of actin dynamics on endosomes may play a role in this disorder.
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cdc42 and the actin related Protein neural wiskott aldrich Syndrome Protein network mediate cellular invasion by cryptosporidium parvum
Infection and Immunity, 2004Co-Authors: Xian Ming Chen, Daniel D Billadeau, James D Orth, Bing Q Huang, Patrick L. Splinter, Mark A. Mcniven, Nicholas F. LarussoAbstract:Cryptosporidium parvum invasion of epithelial cells involves host cell membrane alterations which require a remodeling of the host cell actin cytoskeleton. In addition, an actin plaque, possibly associated with the dense-band region, forms within the host cytoplasm at the host-parasite interface. Here we show that Cdc42 and RhoA, but not Rac1, members of the Rho family of GTPases, are recruited to the host-parasite interface in an in vitro model of human biliary cryptosporidiosis. Interestingly, activation of Cdc42, but not RhoA, was detected in the infected cells. Neural Wiskott-Aldrich Syndrome Protein (N-WASP) and p34-Arc, actin-regulating downstream effectors of Cdc42, were also recruited to the host-parasite interface. Whereas cellular expression of a constitutively active mutant of Cdc42 promoted C. parvum invasion, overexpression of a dominant negative mutant of Cdc42, or depletion of Cdc42 mRNA by short interfering RNA-mediated gene silencing, inhibited C. parvum invasion. Expression of the WA fragment of N-WASP to block associated actin polymerization also inhibited C. parvum invasion. Moreover, inhibition of host cell Cdc42 activation by dominant negative mutation inhibited C. parvum-associated actin remodeling, membrane protrusion, and dense-band formation. In contrast, treatment of cells with a Rho inhibitor, exoenzyme C3, or cellular overexpression of dominant negative mutants of RhoA and Rac1 had no effect on C. parvum invasion. These data suggest that C. parvum invasion of target epithelia results from the organism's ability to activate a host cell Cdc42 GTPase signaling pathway to induce host cell actin remodeling at the attachment site.
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cdc42 and the actin related Protein neural wiskott aldrich Syndrome Protein network mediate cellular invasion by cryptosporidium parvum
Infection and Immunity, 2004Co-Authors: Xian Ming Chen, Daniel D Billadeau, James D Orth, Bing Q Huang, Patrick L. Splinter, Mark A. Mcniven, Nicholas F. LarussoAbstract:Cryptosporidium parvum invasion of epithelial cells involves host cell membrane alterations which require a remodeling of the host cell actin cytoskeleton. In addition, an actin plaque, possibly associated with the dense-band region, forms within the host cytoplasm at the host-parasite interface. Here we show that Cdc42 and RhoA, but not Rac1, members of the Rho family of GTPases, are recruited to the host-parasite interface in an in vitro model of human biliary cryptosporidiosis. Interestingly, activation of Cdc42, but not RhoA, was detected in the infected cells. Neural Wiskott-Aldrich Syndrome Protein (N-WASP) and p34-Arc, actin-regulating downstream effectors of Cdc42, were also recruited to the host-parasite interface. Whereas cellular expression of a constitutively active mutant of Cdc42 promoted C. parvum invasion, overexpression of a dominant negative mutant of Cdc42, or depletion of Cdc42 mRNA by short interfering RNA-mediated gene silencing, inhibited C. parvum invasion. Expression of the WA fragment of N-WASP to block associated actin polymerization also inhibited C. parvum invasion. Moreover, inhibition of host cell Cdc42 activation by dominant negative mutation inhibited C. parvum-associated actin remodeling, membrane protrusion, and dense-band formation. In contrast, treatment of cells with a Rho inhibitor, exoenzyme C3, or cellular overexpression of dominant negative mutants of RhoA and Rac1 had no effect on C. parvum invasion. These data suggest that C. parvum invasion of target epithelia results from the organism's ability to activate a host cell Cdc42 GTPase signaling pathway to induce host cell actin remodeling at the attachment site.
Shiro Suetsugu - One of the best experts on this subject based on the ideXlab platform.
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the wasp wave Protein network connecting the membrane to the cytoskeleton
Nature Reviews Molecular Cell Biology, 2007Co-Authors: Tadaomi Takenawa, Shiro SuetsuguAbstract:Membrane-binding and membrane-deforming Proteins have emerged as binding partners of the Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins that regulate the actin cytoskeleton. Membrane deformation and cytoskeletal reorganization might be coupled in processes that require alteration of membrane shapes, including endocytosis and membrane protrusion. Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins are scaffolds that link upstream signals to the activation of the ARP2/3 complex, leading to a burst of actin polymerization. ARP2/3-complex-mediated actin polymerization is crucial for the reorganization of the actin cytoskeleton at the cell cortex for processes such as cell movement, vesicular trafficking and pathogen infection. Large families of membrane-binding Proteins were recently found to interact with WASP and WAVE family Proteins, therefore providing a new layer of membrane-dependent regulation of actin polymerization.
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the wasp wave Protein network connecting the membrane to the cytoskeleton
Nature Reviews Molecular Cell Biology, 2007Co-Authors: Tadaomi Takenawa, Shiro SuetsuguAbstract:Membrane-binding and membrane-deforming Proteins have emerged as binding partners of the Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins that regulate the actin cytoskeleton. Membrane deformation and cytoskeletal reorganization might be coupled in processes that require alteration of membrane shapes, including endocytosis and membrane protrusion. Wiskott–Aldrich Syndrome Protein (WASP) and WASP-family verprolin-homologous Protein (WAVE) family Proteins are scaffolds that link upstream signals to the activation of the ARP2/3 complex, leading to a burst of actin polymerization. ARP2/3-complex-mediated actin polymerization is crucial for the reorganization of the actin cytoskeleton at the cell cortex for processes such as cell movement, vesicular trafficking and pathogen infection. Large families of membrane-binding Proteins were recently found to interact with WASP and WAVE family Proteins, therefore providing a new layer of membrane-dependent regulation of actin polymerization.
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identification of another actin related Protein arp 2 3 complex binding site in neural wiskott aldrich Syndrome Protein n wasp that complements actin polymerization induced by the arp2 3 complex activating vca domain of n wasp
Journal of Biological Chemistry, 2001Co-Authors: Shiro Suetsugu, Hiroaki Miki, Tadaomi TakenawaAbstract:Abstract Neural Wiskott-Aldrich Syndrome Protein (N-WASP) is an essential regulator of actin cytoskeleton formation via its association with the actin-related Protein (Arp) 2/3 complex. It is believed that the C-terminal Arp2/3 complex-activating domain (verprolin homology, cofilin homology, andacidic (VCA) or C-terminal region of WASP family Proteins domain) of N-WASP is usually kept masked (autoinhibition) but is opened upon cooperative binding of upstream regulators such as Cdc42 and phosphatidylinositol 4,5-bisphosphate (PIP2). However, the mechanisms of autoinhibition and association with Arp2/3 complex are still unclear. We focused on the acidic region of N-WASP because it is thought to interact with Arp2/3 complex and may be involved in autoinhibition. Partial deletion of acidic residues from the VCA portion alone greatly reduced actin polymerization activity, demonstrating that the acidic region contributes to Arp2/3 complex-mediated actin polymerization. Surprisingly, the same partial deletion of the acidic region in full-length N-WASP led to constitutive activity comparable with the activity seen with the VCA portion. Therefore, the acidic region in full-length N-WASP plays an indispensable role in the formation of the autoinhibited structure. This mutant contains WASP-homology (WH) 1 domain with weak affinity to the Arp2/3 complex, leading to activity in the absence of part of the acidic region. Furthermore, the actin comet formed by the ΔWH1 mutant of N-WASP was much smaller than that of wild-type N-WASP. Partial deletion of acidic residues did not affect actin comet size, indicating the importance of the WH1 domain in actin structure formation. Collectively, the acidic region of N-WASP plays an essential role in Arp2/3 complex activation as well as in the formation of the autoinhibited structure, whereas the WH1 domain complements the activation of the Arp2/3 complex achieved through the VCA portion.
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a novel neural wiskott aldrich Syndrome Protein n wasp binding Protein wish induces arp2 3 complex activation independent of cdc42
Journal of Cell Biology, 2001Co-Authors: Maiko Fukuoka, Shiro Suetsugu, Hiroaki Miki, Kiyoko Fukami, Takeshi Endo, Tadaomi TakenawaAbstract:We identified a novel adaptor Protein that contains a Src homology (SH)3 domain, SH3 binding proline-rich sequences, and a leucine zipper-like motif and termed this Protein WASP interacting SH3 Protein (WISH). WISH is expressed predominantly in neural tissues and testis. It bound Ash/Grb2 through its proline-rich regions and neural Wiskott-Aldrich Syndrome Protein (N-WASP) through its SH3 domain. WISH strongly enhanced N-WASP–induced Arp2/3 complex activation independent of Cdc42 in vitro, resulting in rapid actin polymerization. Furthermore, coexpression of WISH and N-WASP induced marked formation of microspikes in Cos7 cells, even in the absence of stimuli. An N-WASP mutant (H208D) that cannot bind Cdc42 still induced microspike formation when coexpressed with WISH. We also examined the contribution of WISH to a rapid actin polymerization induced by brain extract in vitro. Arp2/3 complex was essential for brain extract–induced rapid actin polymerization. Addition of WISH to extracts increased actin polymerization as Cdc42 did. However, WISH unexpectedly could activate actin polymerization even in N-WASP–depleted extracts. These findings suggest that WISH activates Arp2/3 complex through N-WASP–dependent and –independent pathways without Cdc42, resulting in the rapid actin polymerization required for microspike formation.
Adrian J. Thrasher - One of the best experts on this subject based on the ideXlab platform.
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WASP-mediated regulation of anti-inflammatory macrophages is IL-10 dependent and is critical for intestinal homeostasis
Nature Publishing Group, 2018Co-Authors: Amlan Biswas, Jeremy A Goettel, Dror S. Shouval, Alexandra Griffith, Michael Field, Yu Hui Kang, Liza Konnikova, Erin Janssen, Naresh Singh Redhu, Adrian J. ThrasherAbstract:Deficiency in Wiskott-Aldrich Syndrome Protein (WASP) has been associated with autoimmune colitis, but the underlying mechanism is still unclear. Here the authors show that WASP deficiency is associated with defective WASP/DOCK8 complex formation, altered IL-10 signalling, and impaired anti-inflammatory macrophage functions
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migration, and homing
2016Co-Authors: Lisa Westerberg, Adrian J. Thrasher, Malin Larsson, Samantha J Hardy, Eva SeverinsonAbstract:Wiskott-Aldrich Syndrome Protein deficiency leads to reduced B-cell adhesion
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exacerbated experimental arthritis in wiskott aldrich Syndrome Protein deficiency modulatory role of regulatory b cells
European Journal of Immunology, 2014Co-Authors: Gerben Bouma, Luigi D. Notarangelo, Siobhan O Burns, Dessislava Malinova, Claudia Mauri, Natalie A Carter, Mike Recher, Marsilio Adriani, Adrian J. ThrasherAbstract:Patients deficient in the cytoskeletal regulator Wiskott-Aldrich Syndrome Protein (WASp) are predisposed to varied autoimmunity, suggesting it has an important controlling role in participating cells. IL-10-producing regulatory B (Breg) cells are emerging as important mediators of immunosuppressive activity. In experimental, antigen-induced arthritis WASp-deficient (WASp knockout [WAS KO]) mice developed exacerbated disease associated with decreased Breg cells and regulatory T (Treg) cells, but increased Th17 cells in knee-draining LNs. Arthritic WAS KO mice showed increased serum levels of B-cell-activating factor, while their B cells were unresponsive in terms of B-cell-activating factor induced survival and IL-10 production. Adoptive transfer of WT Breg cells ameliorated arthritis in WAS KO recipients and restored a normal balance of Treg and Th17 cells. Mice with B-cell-restricted WASp deficiency, however, did not develop exacerbated arthritis, despite exhibiting reduced Breg- and Treg-cell numbers during active disease, and Th17 cells were not increased over equivalent WT levels. These findings support a contributory role for defective Breg cells in the development of WAS-related autoimmunity, but demonstrate that functional competence in other regulatory populations can be compensatory. A properly regulated cytoskeleton is therefore important for normal Breg-cell activity and complementation of defects in this lineage is likely to have important therapeutic benefits.
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integrin linked kinase ilk regulates podosome maturation and stability in dendritic cells
The International Journal of Biochemistry & Cell Biology, 2014Co-Authors: Mercedes Griera, Adrian J. Thrasher, Gareth E Jones, Ines M Anton, Inmaculada Banonrodriguez, Ester Martinvillar, Michael P Blundell, Manuel Rodriguezpuyol, Yolanda CalleAbstract:Podosomes are integrin-based adhesions fundamental for stabilisation of the leading lamellae in migrating dendritic cells (DCs) and for extracellular matrix (ECM) degradation. We have previously shown that soluble factors and chemokines such as SDF 1-a trigger podosome initiation whereas integrin ligands promote podosome maturation and stability in DCs. The exact intracellular signalling pathways that regulate the sequential organisation of podosomal components in response to extracellular cues remain largely undetermined. The Wiskott Aldrich Syndrome Protein (WASP) mediates actin polymerisation and the initial recruitment of integrins and associated Proteins in a circular configuration surrounding the core of filamentous actin (F-actin) during podosome initiation. We have now identified integrin linked kinase (ILK) surrounding the podosomal actin core. We report that DC polarisation in response to chemokines and the assembly of actin cores during podosome initiation require PI3K-dependent clustering of the Wiskott Aldrich Syndrome Protein (WASP) in puncta independently of ILK. ILK is essential for the clustering of integrins and associated Proteins leading to podosome maturation and stability that are required for degradation of the subjacent extracellular matrix and the invasive motility of DCs across connective tissue barriers. We conclude that WASP regulates DCs polarisation for migration and initiation of actin polymerisation downstream of PI3K in nascent podosomes. Subsequently, ILK mediates the accumulation of integrin-associated Proteins during podosome maturation and stability for efficient degradation of the subjacent ECM during the invasive migration of DCs.
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tyrosine phosphorylation of wasp promotes calpain mediated podosome disassembly
Haematologica, 2012Co-Authors: Lee Macpherson, Adrian J. Thrasher, Gareth E Jones, James Monypenny, Michael P Blundell, Giles O Cory, Jessica Tomegarcia, Yolanda CalleAbstract:Podosomes are actin-based adhesions involved in migration of cells that have to cross tissue boundaries such as myeloid cells. The Wiskott Aldrich Syndrome Protein regulates de novo actin polymerization during podosome formation and it is cleaved by the protease calpain during podosome disassembly. The mechanisms that may induce the Wiskott Aldrich Syndrome Protein cleavage by calpain remain undetermined. We now report that in myeloid cells, tyrosine phosphorylation of the Wiskott Aldrich Syndrome Protein-tyrosine291 (Human)/tyrosine293 (mouse) not only enhances Wiskott Aldrich Syndrome Protein-mediated actin polymerization but also promotes its calpain-dependent degradation during podosome disassembly. We also show that activation of the Wiskott Aldrich Syndrome Protein leading to podosome formation occurs independently of tyrosine phosphorylation in spleen-derived dendritic cells. We conclude that tyrosine phosphorylation of the Wiskott Aldrich Syndrome Protein integrates dynamics of actin and cell adhesion Proteins during podosome disassembly required for mobilization of myeloid cells during the immune response.
Scott B. Snapper - One of the best experts on this subject based on the ideXlab platform.
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Nuclear Wiskott–Aldrich Syndrome Protein co-regulates T cell factor 1-mediated transcription in T cells
Genome Medicine, 2017Co-Authors: Nikolai V Kuznetsov, Marisa A. P. Baptista, Marton Keszei, Scott B. Snapper, Bader Almuzzaini, Joanna S Kritikou, Mariana M S Oliveira, Piergiorgio Percipalle, Lisa S WesterbergAbstract:Background The Wiskott–Aldrich Syndrome Protein (WASp) family of actin-nucleating factors are present in the cytoplasm and in the nucleus. The role of nuclear WASp for T cell development remains incompletely defined. Methods We performed WASp chromatin immunoprecipitation and deep sequencing (ChIP-seq) in thymocytes and spleen CD4^+ T cells. Results WASp was enriched at genic and intergenic regions and associated with the transcription start sites of Protein-coding genes. Thymocytes and spleen CD4^+ T cells showed 15 common WASp-interacting genes, including the gene encoding T cell factor (TCF)12. WASp KO thymocytes had reduced nuclear TCF12 whereas thymocytes expressing constitutively active WASp^L272P and WASp^I296T had increased nuclear TCF12, suggesting that regulated WASp activity controlled nuclear TCF12. We identify a putative DNA element enriched in WASp ChIP-seq samples identical to a TCF1-binding site and we show that WASp directly interacted with TCF1 in the nucleus. Conclusions These data place nuclear WASp in proximity with TCF1 and TCF12, essential factors for T cell development.
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nuclear wiskott aldrich Syndrome Protein co regulates t cell factor 1 mediated transcription in t cells
Genome Medicine, 2017Co-Authors: Nikolai V Kuznetsov, Marisa A. P. Baptista, Marton Keszei, Scott B. Snapper, Bader Almuzzaini, Joanna S Kritikou, Mariana M S Oliveira, Piergiorgio PercipalleAbstract:The Wiskott–Aldrich Syndrome Protein (WASp) family of actin-nucleating factors are present in the cytoplasm and in the nucleus. The role of nuclear WASp for T cell development remains incompletely defined. We performed WASp chromatin immunoprecipitation and deep sequencing (ChIP-seq) in thymocytes and spleen CD4+ T cells. WASp was enriched at genic and intergenic regions and associated with the transcription start sites of Protein-coding genes. Thymocytes and spleen CD4+ T cells showed 15 common WASp-interacting genes, including the gene encoding T cell factor (TCF)12. WASp KO thymocytes had reduced nuclear TCF12 whereas thymocytes expressing constitutively active WASpL272P and WASpI296T had increased nuclear TCF12, suggesting that regulated WASp activity controlled nuclear TCF12. We identify a putative DNA element enriched in WASp ChIP-seq samples identical to a TCF1-binding site and we show that WASp directly interacted with TCF1 in the nucleus. These data place nuclear WASp in proximity with TCF1 and TCF12, essential factors for T cell development.
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neuronal wiskott aldrich Syndrome Protein regulates tgf β1 mediated lung vascular permeability
The FASEB Journal, 2016Co-Authors: Brant M Wagener, Scott B. Snapper, Anni Zheng, Xueke Zhao, Pulin Che, Angela Brandon, Naseem Anjum, Judy Creighton, Junlin Guan, Qimei HanAbstract:TGF-β1 induces an increase in paracellular permeability and actin stress fiber formation in lung microvascular endothelial and alveolar epithelial cells via small Rho GTPase. The molecular mechanism involved is not fully understood. Neuronal Wiskott-Aldrich Syndrome Protein (N-WASP) has an essential role in actin structure dynamics. We hypothesized that N-WASP plays a critical role in these TGF-β1-induced responses. In these cell monolayers, we demonstrated that N-WASP down-regulation by short hairpin RNA prevented TGF-β1-mediated disruption of the cortical actin structure, actin stress filament formation, and increased permeability. Furthermore, N-WASP down-regulation blocked TGF-β1 activation mediated by IL-1β in alveolar epithelial cells, which requires actin stress fiber formation. Control short hairpin RNA had no effect on these TGF-β1-induced responses. TGF-β1-induced phosphorylation of Y256 of N-WASP via activation of small Rho GTPase and focal adhesion kinase mediates TGF-β1-induced paracellular permeability and actin cytoskeleton dynamics. In vivo, compared with controls, N-WASP down-regulation increases survival and prevents lung edema in mice induced by bleomycin exposure-a lung injury model in which TGF-β1 plays a critical role. Our data indicate that N-WASP plays a crucial role in the development of TGF-β1-mediated acute lung injury by promoting pulmonary edema via regulation of actin cytoskeleton dynamics.-Wagener, B. M., Hu, M., Zheng, A., Zhao, X., Che, P., Brandon, A., Anjum, N., Snapper, S., Creighton, J., Guan, J.-L., Han, Q., Cai, G.-Q., Han, X., Pittet, J.-F., Ding, Q. Neuronal Wiskott-Aldrich Syndrome Protein regulates TGF-β1-mediated lung vascular permeability.
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neural wiskott aldrich Syndrome Protein modulates wnt signaling and is required for hair follicle cycling in mice
Journal of Clinical Investigation, 2010Co-Authors: Anna Lyubimova, John J Garber, Geeta Upadhyay, Andrey A Sharov, Florentina Anastasoaie, Vijay Yajnik, George Cotsarelis, Gian Paolo Dotto, Vladimir A Botchkarev, Scott B. SnapperAbstract:The Rho family GTPases Cdc42 and Rac1 are critical regulators of the actin cytoskeleton and are essential for skin and hair function. Wiskott-Aldrich Syndrome family Proteins act downstream of these GTPases, controlling actin assembly and cytoskeletal reorganization, but their role in epithelial cells has not been characterized in vivo. Here, we used a conditional knockout approach to assess the role of neural Wiskott-Aldrich Syndrome Protein (N-WASP), the ubiquitously expressed Wiskott-Aldrich Syndrome-like (WASL) Protein, in mouse skin. We found that N-WASP deficiency in mouse skin led to severe alopecia, epidermal hyperproliferation, and ulceration, without obvious effects on epidermal differentiation and wound healing. Further analysis revealed that the observed alopecia was likely the result of a progressive and ultimately nearly complete block in hair follicle (HF) cycling by 5 months of age. N-WASP deficiency also led to abnormal proliferation of skin progenitor cells, resulting in their depletion over time. Furthermore, N-WASP deficiency in vitro and in vivo correlated with decreased GSK-3beta phosphorylation, decreased nuclear localization of beta-catenin in follicular keratinocytes, and decreased Wnt-dependent transcription. Our results indicate a critical role for N-WASP in skin function and HF cycling and identify a link between N-WASP and Wnt signaling. We therefore propose that N-WASP acts as a positive regulator of beta-catenin-dependent transcription, modulating differentiation of HF progenitor cells.
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lymphocyte dependent and th2 cytokine associated colitis in mice deficient in wiskott aldrich Syndrome Protein
Gastroenterology, 2007Co-Authors: Deanna D Nguyen, Michel H. Maillard, Cathryn R Nagler, Atul K Bhan, Vinicius Cotta De Almeida, Emiko Mizoguchi, Christoph Klein, Ivan J Fuss, Atsushi Mizoguchi, Scott B. SnapperAbstract:Background & Aims: Controversy exists as to whether patients with inflammatory bowel disease have an underlying immunodeficiency. We have focused on a murine model of the Wiskott-Aldrich Syndrome, an immunodeficiency in which autoimmunity can manifest in the form of an inflammatory bowel disease-like illness. Wiskott-Aldrich Syndrome Protein (WASP) deficiency in mice results in similar clinical features. Herein, we characterized the colitis in WASP-deficient mice. Methods: WASP-deficient mice were followed clinically and histologically. Immunologic studies were performed to determine the pathogenic cell population(s), the predominant cytokine expression pattern, and the role of cytokine(s) in colitis pathogenesis. Results: All WASP-deficient mice develop colitis by 6 months of age. Lymphocytes are required for disease induction, and CD4+ T cells from WASP-deficient mice are sufficient to induce disease in lymphocyte-deficient hosts. Lamina propria preparations from WASP-deficient mice demonstrated elevations in interferon-γ, interleukin (IL)-4, and IL-13 levels but decreased IL-6 and no difference in IL-17 expression in comparison with wild-type controls. Treatment with neutralizing antibody to IL-4, but not to interferon-γ, abrogated colitis development. However, mice deficient in both WASP and IL-4 showed no difference in histologic colitis scores at 24 weeks of age compared with WASP-deficient mice. Conclusions: These results demonstrate a critical role for lymphocytes and a relative T helper 2 cytokine predominance in the colitis associated with WASP-deficient mice. This is the only model of colitis with elevated T helper 2 cytokines and aberrant natural regulatory T cell function and is unique in having a human disease counterpart with similar defects.
