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Carl P. Blobel - One of the best experts on this subject based on the ideXlab platform.
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Role of ADAM17 in endotoxin-induced pulmonary inflammation
European Respiratory Journal, 2011Co-Authors: Daniela Dreymueller, Carl P. Blobel, Franz M. Hess, Christian Martin, Tanja Kogel, Keisuke Horiuchi, Stefan Uhlig, Andreas LudwigAbstract:Acute lung inflammation is associated with enhanced vascular permeability and leukocyte recruitment. Several proinflammatory, soluble and surface-expressed mediators, including TNFα, TNFR1/2, amphiregulin, IL-6R, IL-1R, L-selectin, CX3CL1, and JAMs may become released by the activity of the metalloproteinases ADAM10 and ADAM17. We examined the role of these proteases in vascular permeability and leukocyte transmigration in vitro by pharmacological inhibition and lentiviral-mediated siRNA knockdown of ADAM10 and ADAM17. The in vivo role of these proteases was studied in a murine model of LPS-induced lung injury by pharmacological inhibition. The relevance of ADAM17 was further analyzed by knockout of ADAM17 in endothelial or smooth muscle cells. The BAL protein levels and the wet/dry-ratio served as markers of vascular permeability and edema formation. Cell recruitment to the alveolar space and lung tissue was analyzed by flow cytometry; cytokines were determined by ELISA. In vitro, transmigration of neutrophils to IL-8 through pulmonary endothelial cells was reduced by pharmacological inhibition as well as knockdown of ADAM10 or ADAM17. LPS-mediated induction of permeability was reduced by pharmacological inhibition, but not by ADAM10 knockdown, indicating a predominant role of ADAM17 in the regulation of endothelial permeability. In vivo, LPS challenge increased the wet/dry-ratio as well as the BAL levels of protein, TNFα, IL-6 and leukocytes. All these effects were largely prevented by inhibitor application or by knockout of ADAM17 in smooth muscle or endothelial cells. These results indicate that local ADAM17 is involved in the onset of inflammation and tissue injury during endotoxin-induced lung inflammation.
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ADAM17 is regulated by a rapid and reversible mechanism that controls access to its catalytic site
Journal of Cell Science, 2010Co-Authors: Sylvain Le Gall, Paul Saftig, Karina Reiss, Thorsten Maretzky, Priya D Issuree, Xiaoda Niu, Rama Khokha, Daniel Lundell, Carl P. BlobelAbstract:Protein ectodomain shedding is crucial for cell–cell interactions because it controls the bioavailability of soluble tumor necrosis factor-α (TNFα) and ligands of the epidermal growth factor (EGF) receptor, and the release of many other membrane proteins. Various stimuli can rapidly trigger ectodomain shedding, yet much remains to be learned about the identity of the enzymes that respond to these stimuli and the mechanisms underlying their activation. Here, we demonstrate that the membrane-anchored metalloproteinase ADAM17, but not ADAM10, is the sheddase that rapidly responds to the physiological signaling pathways stimulated by thrombin, EGF, lysophosphatidic acid and TNFα. Stimulation of ADAM17 is swift and quickly reversible, and does not depend on removal of its inhibitory pro-domain by pro-protein convertases, or on dissociation of an endogenous inhibitor, TIMP3. Moreover, activation of ADAM17 by physiological stimuli requires its transmembrane domain, but not its cytoplasmic domain, arguing against inside–out signaling via cytoplasmic phosphorylation as the underlying mechanism. Finally, experiments with the tight binding hydroxamate inhibitor DPC333, used here to probe the accessibility of the active site of ADAM17, demonstrate that this inhibitor can quickly bind to ADAM17 in stimulated, but not quiescent cells. These findings support the concept that activation of ADAM17 involves a rapid and reversible exposure of its catalytic site.
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stimulation of platelet derived growth factor receptor β pdgfrβ activates ADAM17 and promotes metalloproteinase dependent cross talk between the pdgfrβ and epidermal growth factor receptor egfr signaling pathways
Journal of Biological Chemistry, 2010Co-Authors: Karen Mendelson, Carl P. Blobel, Steven Swendeman, Paul SaftigAbstract:Binding of the platelet-derived growth factor (PDGF)-B to its receptor PDGFRβ promotes proliferation, migration, and recruitment of pericytes and smooth muscle cells to endothelial cells, serving to stabilize developing blood vessels. The main goals of this study were to determine whether the extracellular domain of the PDGFRβ can be proteolytically released from cell membranes and, if so, to identify the responsible sheddase and determine whether activation of the PDGFRβ stimulates its shedding and potentially that of other membrane proteins. We found that the PDGFRβ is shed from cells by a metalloproteinase and used loss-of-function experiments to identify ADAM10 as the sheddase responsible for constitutive and ionomycin-stimulated processing of the PDGFRβ. Moreover, we showed that ligand-dependent activation of the PDGFRβ does not trigger its own shedding by ADAM10, but instead it stimulates ADAM17 and shedding of substrates of ADAM17, including tumor necrosis factor α and transforming growth factor α. Finally, we demonstrated that treatment of mouse embryonic fibroblasts with PDGF-B triggers a metalloproteinase-dependent cross-talk between the PDGFRβ and the epidermal growth factor receptor (EGFR)/ERK1/2 signaling axis that is also critical for PDGF-B-stimulated cell migration, most likely via ADAM17-dependent release and activation of ligands of the EGFR. This study identifies the principal sheddase for the PDGFRβ and provides new insights into the mechanism of PDGFRβ-dependent signal transduction and cross-talk with the EGFR.
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vegf a stimulates ADAM17 dependent shedding of vegfr2 and crosstalk between vegfr2 and erk signaling
Circulation Research, 2008Co-Authors: Steven Swendeman, Gisela Weskamp, Keisuke Horiuchi, Karen Mendelson, Urban Deutsch, Peggy Scherle, Andrea T Hooper, Shahin Rafii, Carl P. BlobelAbstract:Vascular endothelial growth factor (VEGF)-A and the VEGF receptors are critical for regulating angiogenesis during development and homeostasis and in pathological conditions, such as cancer and proliferative retinopathies. Most effects of VEGF-A are mediated by the VEGFR2 and its coreceptor, neuropilin (NRP)-1. Here, we show that VEGFR2 is shed from cells by the metalloprotease disintegrin ADAM17, whereas NRP-1 is released by ADAM10. VEGF-A enhances VEGFR2 shedding by ADAM17 but not shedding of NRP-1 by ADAM10. VEGF-A activates ADAM17 via the extracellular signal-regulated kinase (ERK) and mitogen-activated protein kinase pathways, thereby also triggering shedding of other ADAM17 substrates, including tumor necrosis factor alpha, transforming growth factor alpha, heparin-binding epidermal growth factor-like growth factor, and Tie-2. Interestingly, an ADAM17-selective inhibitor shortens the duration of VEGF-A-stimulated ERK phosphorylation in human umbilical vein endothelial cells, providing evidence for an ADAM17-dependent crosstalk between the VEGFR2 and ERK signaling. Targeting the sheddases of VEGFR2 or NRP-1 might offer new opportunities to modulate VEGF-A signaling, an already-established target for treatment of pathological neovascularization.
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metalloproteases regulate t cell proliferation and effector function via lag 3
The EMBO Journal, 2007Co-Authors: Nianyu Li, Kate M Vignali, Bret S E Heale, Karen Forbes, John J. Rossi, Roy A. Black, Dieter Hartmann, Paul Saftig, Yao Wang, Carl P. BlobelAbstract:Tight control of T‐cell proliferation and effector function is essential to ensure an effective but appropriate immune response. Here, we reveal that this is controlled by the metalloprotease‐mediated cleavage of LAG‐3, a negative regulatory protein expressed by all activated T cells. We show that LAG‐3 cleavage is mediated by two transmembrane metalloproteases, ADAM10 and ADAM17, with the activity of both modulated by two distinct T‐cell receptor (TCR) signaling‐dependent mechanisms. ADAM10 mediates constitutive LAG‐3 cleavage but increases ∼12‐fold following T‐cell activation, whereas LAG‐3 shedding by ADAM17 is induced by TCR signaling in a PKCθ‐dependent manner. LAG‐3 must be cleaved from the cell surface to allow for normal T‐cell activation as noncleavable LAG‐3 mutants prevented proliferation and cytokine production. Lastly, ADAM10 knockdown reduced wild‐type but not LAG‐3 −/− T‐cell proliferation. These data demonstrate that LAG‐3 must be cleaved to allow efficient T‐cell proliferation and cytokine production and establish a novel paradigm in which T‐cell expansion and function are regulated by metalloprotease cleavage with LAG‐3 as its sole molecular target.
Paul Saftig - One of the best experts on this subject based on the ideXlab platform.
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230: Unraveling the role of ADAM17 in IL-6 trans-signaling
Cytokine, 2013Co-Authors: Jeanette Schwarz, Paul Saftig, Isabell Yan, Olga Will, Stefan-rose-john, Hans-willi Mittrücker, Athena ChalarisAbstract:IL-6 is a key regulator of immune responses after bacterial infection. IL-6 signaling is mediated via the receptor subunits IL-6R and gp130. The signal transducing subunit gp130 is ubiquitously expressed whereas IL-6R expression is restricted to hepatocytes and some leukocytes. The IL-6R can be cleaved from the cell surface by ADAM proteases. The soluble form of the IL-6R (sIL-6R) has the same IL-6 binding affinity as the membrane-bound receptor. The resulting IL-6/sIL-6R complex activates cells, which only express gp130 on their cell surface, a process called trans-signaling. Thus, IL-6-transsignaling following IL-6R proteolysis essentially renders all cells of the body responsive to IL-6. The proteolytic web controlling IL-6R shedding in vivo under pathophysiological conditions is poorly characterized. Recently, it was demonstrated that human IL-6R is a substrate for the protease ADAM17 in contrast to the murine ADAM17, which is mainly cleaved by ADAM10. However, these data were raised in cell culture systems. We analyzed IL-6R shedding in vivo on leukocytes after infection with Listeria monocytogenes or LPS-challenge of ADAM17 and ADAM10-deficient mice. ADAM17 and ADAM10 knockout mice are not viable. For this reason we generated a hypomorphic ADAM17 mouse model which expresses only 5% of the normal ADAM17 levels. Additionally we use conditional ADAM10 mice with ADAM10 deleted either in monocytes or Tcells. Listeria infection led to massive shedding of the IL-6R on Tcells and inflammatory monocytes. Further we could demonstrate that Listeria -induced IL-6R cleavage is abrogated in hypomorphic ADAM17 ex/ex mice. Additionally we can show that serum levels of sIL-6R are elevated after LPS challenge of wildtype but not ADAM17 ex/ex mice. These results strongly suggest that ADAM17 is the main IL-6R sheddase under pathophysiological conditions. In future experiments we will evaluate the contribution of the protease ADAM10 in mediating IL-6R shedding to uncover the proteolytic steps involved in IL-6 trans-signaling.
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the a disintegrin and metalloproteases adam10 and ADAM17 novel drug targets with therapeutic potential
European Journal of Cell Biology, 2011Co-Authors: Paul Saftig, Karina ReissAbstract:Proteolytic ectodomain release, a process known as "shedding", has been recognised as a key mechanism for regulating the function of a diversity of cell surface proteins. A Disintegrin And Metalloproteinases (ADAMs) have emerged as the major proteinase family that mediates ectodomain shedding. Dysregulation of ectodomain shedding is associated with autoimmune and cardiovascular diseases, neurodegeneration, infection, inflammation and cancer. Therefore, ADAMs are increasingly regarded as attractive targets for novel therapies. ADAM10 and its close relative ADAM17 (TNF-alpha converting enzyme (TACE)) have been studied in particular in the context of ectodomain shedding and have been demonstrated as key molecules in most of the shedding events characterised to date. Whereas the level of expression of ADAM10 may be of importance in cancer and neurodegenerative disorders, ADAM17 mainly coordinates pro- and anti-inflammatory activities during immune response. Despite the high therapeutical potential of ADAM inhibition, all clinical trials using broad-spectrum metalloprotease inhibitors have failed so far. This review will cover the emerging roles of both ADAM10 and ADAM17 in the regulation of major physiological and developmental pathways and will discuss the suitability of specifically modulating the activities of both proteases as a feasible way to inhibit inflammatory states, cancer and neurodegeneration.
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ADAM17 is regulated by a rapid and reversible mechanism that controls access to its catalytic site
Journal of Cell Science, 2010Co-Authors: Sylvain Le Gall, Paul Saftig, Karina Reiss, Thorsten Maretzky, Priya D Issuree, Xiaoda Niu, Rama Khokha, Daniel Lundell, Carl P. BlobelAbstract:Protein ectodomain shedding is crucial for cell–cell interactions because it controls the bioavailability of soluble tumor necrosis factor-α (TNFα) and ligands of the epidermal growth factor (EGF) receptor, and the release of many other membrane proteins. Various stimuli can rapidly trigger ectodomain shedding, yet much remains to be learned about the identity of the enzymes that respond to these stimuli and the mechanisms underlying their activation. Here, we demonstrate that the membrane-anchored metalloproteinase ADAM17, but not ADAM10, is the sheddase that rapidly responds to the physiological signaling pathways stimulated by thrombin, EGF, lysophosphatidic acid and TNFα. Stimulation of ADAM17 is swift and quickly reversible, and does not depend on removal of its inhibitory pro-domain by pro-protein convertases, or on dissociation of an endogenous inhibitor, TIMP3. Moreover, activation of ADAM17 by physiological stimuli requires its transmembrane domain, but not its cytoplasmic domain, arguing against inside–out signaling via cytoplasmic phosphorylation as the underlying mechanism. Finally, experiments with the tight binding hydroxamate inhibitor DPC333, used here to probe the accessibility of the active site of ADAM17, demonstrate that this inhibitor can quickly bind to ADAM17 in stimulated, but not quiescent cells. These findings support the concept that activation of ADAM17 involves a rapid and reversible exposure of its catalytic site.
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stimulation of platelet derived growth factor receptor β pdgfrβ activates ADAM17 and promotes metalloproteinase dependent cross talk between the pdgfrβ and epidermal growth factor receptor egfr signaling pathways
Journal of Biological Chemistry, 2010Co-Authors: Karen Mendelson, Carl P. Blobel, Steven Swendeman, Paul SaftigAbstract:Binding of the platelet-derived growth factor (PDGF)-B to its receptor PDGFRβ promotes proliferation, migration, and recruitment of pericytes and smooth muscle cells to endothelial cells, serving to stabilize developing blood vessels. The main goals of this study were to determine whether the extracellular domain of the PDGFRβ can be proteolytically released from cell membranes and, if so, to identify the responsible sheddase and determine whether activation of the PDGFRβ stimulates its shedding and potentially that of other membrane proteins. We found that the PDGFRβ is shed from cells by a metalloproteinase and used loss-of-function experiments to identify ADAM10 as the sheddase responsible for constitutive and ionomycin-stimulated processing of the PDGFRβ. Moreover, we showed that ligand-dependent activation of the PDGFRβ does not trigger its own shedding by ADAM10, but instead it stimulates ADAM17 and shedding of substrates of ADAM17, including tumor necrosis factor α and transforming growth factor α. Finally, we demonstrated that treatment of mouse embryonic fibroblasts with PDGF-B triggers a metalloproteinase-dependent cross-talk between the PDGFRβ and the epidermal growth factor receptor (EGFR)/ERK1/2 signaling axis that is also critical for PDGF-B-stimulated cell migration, most likely via ADAM17-dependent release and activation of ligands of the EGFR. This study identifies the principal sheddase for the PDGFRβ and provides new insights into the mechanism of PDGFRβ-dependent signal transduction and cross-talk with the EGFR.
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metalloproteases regulate t cell proliferation and effector function via lag 3
The EMBO Journal, 2007Co-Authors: Nianyu Li, Kate M Vignali, Bret S E Heale, Karen Forbes, John J. Rossi, Roy A. Black, Dieter Hartmann, Paul Saftig, Yao Wang, Carl P. BlobelAbstract:Tight control of T‐cell proliferation and effector function is essential to ensure an effective but appropriate immune response. Here, we reveal that this is controlled by the metalloprotease‐mediated cleavage of LAG‐3, a negative regulatory protein expressed by all activated T cells. We show that LAG‐3 cleavage is mediated by two transmembrane metalloproteases, ADAM10 and ADAM17, with the activity of both modulated by two distinct T‐cell receptor (TCR) signaling‐dependent mechanisms. ADAM10 mediates constitutive LAG‐3 cleavage but increases ∼12‐fold following T‐cell activation, whereas LAG‐3 shedding by ADAM17 is induced by TCR signaling in a PKCθ‐dependent manner. LAG‐3 must be cleaved from the cell surface to allow for normal T‐cell activation as noncleavable LAG‐3 mutants prevented proliferation and cytokine production. Lastly, ADAM10 knockdown reduced wild‐type but not LAG‐3 −/− T‐cell proliferation. These data demonstrate that LAG‐3 must be cleaved to allow efficient T‐cell proliferation and cytokine production and establish a novel paradigm in which T‐cell expansion and function are regulated by metalloprotease cleavage with LAG‐3 as its sole molecular target.
Jurgen Scheller - One of the best experts on this subject based on the ideXlab platform.
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human and murine interleukin 23 receptors are novel substrates for a disintegrin and metalloproteases adam10 and ADAM17
Journal of Biological Chemistry, 2016Co-Authors: Manuel Franke, Christoph Garbers, Doreen M Floss, Christoph Beckerpauly, Bjorn Rabe, Jutta Schroder, Niloufar Monhasery, Theresa Ackfeld, Thorben M Hummel, Jurgen SchellerAbstract:IL-23 (interleukin 23) regulates immune responses against pathogens and plays a major role in the differentiation and maintenance of TH17 cells and the development of autoimmune diseases and cancer. The IL-23 receptor (IL-23R) complex consists of the unique IL-23R and the common IL-12 receptor β1 (IL-12Rβ1). Differential splicing generates antagonistic soluble IL-23R (sIL-23R) variants, which might limit IL-23-mediated immune responses. Here, ectodomain shedding of human and murine IL-23R was identified as an alternative pathway for the generation of sIL-23R. Importantly, proteolytically released sIL-23R has IL-23 binding activity. Shedding of IL-23R was induced by stimulation with the phorbol ester phorbol 12-myristate 13-acetate (PMA), but not by ionomycin. PMA-induced shedding was abrogated by an ADAM (A disintegrin and metalloprotease) 10 and 17 selective inhibitor, but not by an ADAM10 selective inhibitor. ADAM17-deficient but not ADAM10-deficient HEK293 cells failed to shed IL-23R after PMA stimulation, demonstrating that ADAM17 but not ADAM10 cleaves the IL-23R. Constitutive shedding was, however, inhibited by an ADAM10 selective inhibitor. Using deletions and specific amino acid residue exchanges, we identified critical determinants of ectodomain shedding within the stalk region of the IL-23R. Finally, interaction studies identified domains 1 and 3 of the IL-23R as the main ADAM17 binding sites. In summary, we describe human and murine IL-23R as novel targets for protein ectodomain shedding by ADAM10 and ADAM17.
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t cell immunoglobulin and mucin domain 2 tim 2 is a target of adam10 mediated ectodomain shedding
FEBS Journal, 2014Co-Authors: Christin Dewitz, Athena Chalaris, Jurgen Scheller, Karina Reiss, Katja Mollerhackbarth, Olga Schweigert, Stefan RosejohnAbstract:T-cell immunoglobulin and mucin domain (TIM)-2 is expressed on activated B cells. Here, we provide evidence that murine TIM-2 is a target of ADAM10-mediated ectodomain shedding, resulting in the generation of a soluble form of TIM-2. We identified ADAM10 but not ADAM17 as the major sheddase of TIM-2, as shown by pharmacological ADAM10 inhibition and with ADAM10-deficient and ADAM17-deficient murine embryonic fibroblasts. Ionomycin-induced or 2′(3′)-O-(4-benzoylbenzoyl) ATP triethylammonium salt-induced shedding of TIM-2 was abrogated by deletion of 10 juxtamembrane amino acids from the stalk region but not by deletion of two further N-terminally located blocks of 10 amino acids, indicating a membrane-proximal cleavage site. TIM-2 lacking the intracellular domain was cleaved after ionomycin or 2′ (3′)-O-(4-benzoylbenzoyl) ATP triethylammonium salt treatment, indicating that this domain was not involved in the regulation of ectodomain shedding. Moreover, TIM-2 shedding was negatively controlled by calmodulin. Shed and soluble TIM-2 interacted with H-ferritin. In summary, we describe TIM-2 as a novel target for ADAM10-mediated ectodomain shedding, and reveal the involvement of ADAM proteases in cellular iron homeostasis.
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a disintegrin and metalloprotease adam 10 and ADAM17 are major sheddases of t cell immunoglobulin and mucin domain 3 tim 3
Journal of Biological Chemistry, 2013Co-Authors: Katja Mollerhackbarth, Christoph Garbers, Stefan Rosejohn, Christin Dewitz, Olga Schweigert, Ahmad Trad, Jurgen SchellerAbstract:T cell immunoglobulin and mucin domain 3 (Tim-3) dampens the response of CD4+ and CD8+ effector T cells via induction of cell death and/or T cell exhaustion and enhances the ability of macrophages to clear pathogens via binding to galectin 9. Here we provide evidence that human Tim-3 is a target of A disintegrin and metalloprotease (ADAM)-mediated ectodomain shedding resulting in a soluble form of Tim-3. We identified ADAM10 and ADAM17 as major sheddases of Tim-3 as shown by ADAM-specific inhibitors and the ADAM10 pro-domain in HEK293 cells and ADAM10/ADAM17-deficient murine embryonic fibroblasts. PMA-induced shedding of Tim-3 was abrogated by deletion of amino acids Glu181–Asp190 of the stalk region and Tim-3 lacking the intracellular domain was not efficiently cleaved after PMA stimulation. Surprisingly, a single lysine residue within the intracellular domain rescues shedding of Tim-3. Shedding of endogenous Tim-3 was found in primary human CD14+ monocytes after PMA and ionomycin stimulation. Importantly, the recently described down-regulation of Tim-3 from Toll-like receptor-activated CD14+ monocytes was caused by ADAM10- and ADAM17-mediated shedding. Inhibition of Tim-3 shedding from lipopolysaccharide-induced monocytes did not influence lipopolysaccharide-induced TNFα and IL-6 but increases IL-12 expression. In summary, we describe Tim-3 as novel target for ADAM-mediated ectodomain shedding and suggest a role of Tim-3 shedding in TLR-mediated immune responses of CD14+ monocytes.
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minimal interleukin 6 il 6 receptor stalk composition for il 6 receptor shedding and il 6 classic signaling
Journal of Biological Chemistry, 2013Co-Authors: Paul Baran, Jurgen Scheller, Rebecca Nitz, Joachim Grotzinger, Christoph GarbersAbstract:Abstract Signaling of the pleiotropic cytokine Interleukin-6 (IL-6) is coordinated by membrane-bound and soluble forms of the IL-6 receptor (IL-6R) in processes called classic and trans-signaling, respectively. The soluble IL-6R is mainly generated by ADAM10- and ADAM17-mediated ectodomain shedding. Little is known about the role of the 52-amino acid-residue-long IL-6R stalk region in shedding and signal transduction. Therefore, we generated and analyzed IL-6R stalk region deletion variants for cleavability and biological activity. Deletion of 10 amino acids of the stalk region surrounding the ADAM17 cleavage site substantially blocked IL-6R proteolysis by ADAM17 but only slightly affected proteolysis by ADAM10. Interestingly, additional deletion of the remaining five juxtamembrane-located amino acids also abrogated ADAM10-mediated IL-6R shedding. Larger deletions within the stalk region, that do not necessarily include the ADAM17 cleavage site, also reduced ADAM10 and ADAM17-mediated IL-6R shedding, questioning the importance of cleavage site recognition. Furthermore, we show that a 22-amino acid-long stalk region is minimally required for IL-6 classic signaling. The gp130 cytokine binding sites are separated from the plasma membrane by ∼96 A. 22 amino acid residues, however, span maximally 83.6 A (3.8 A/amino acid), indicating that the three juxtamembrane fibronectin domains of gp130 are not necessarily elongated but somehow flexed to allow IL-6 classic signaling. Our findings underline a dual role of the IL-6R stalk region in IL-6 signaling. In IL-6 trans-signaling, it regulates proper proteolysis by ADAM10 and ADAM17. In IL-6 classic-signaling, it acts as a spacer to ensure IL-6·IL-6R·gp130 signal complex formation.
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species specificity of adam10 and ADAM17 proteins in interleukin 6 il 6 trans signaling and novel role of adam10 in inducible il 6 receptor shedding
Journal of Biological Chemistry, 2011Co-Authors: Christoph Garbers, Dorte Meyer, Marcia L. Moss, Nathalie Janner, Athena Chalaris, Doreen M Floss, Friedrich Kochnolte, Stefan Rosejohn, Jurgen SchellerAbstract:Hypomorphic ADAM17ex/ex mice showed defects in mucosal regeneration due to inefficient enhanced GFR shedding. ADAM17 is the main sheddase of interleukin-6 receptor (IL-6R) to induce IL-6 trans-signaling. However, serum levels of soluble murine IL-6R were not reduced in ADAM17ex/ex mice, and murine ADAM17 was not the major sheddase of murine IL-6R. Shedding of murine IL-6R by murine ADAM17 was rescued in chimeric murine IL-6R proteins containing any extracellular domain but not the transmembrane and intracellular domain of human IL-6R. Apoptosis is a physiological stimulus of ADAM17-mediated shedding of human IL-6R. Even though apoptosis induced IL-6R shedding in mice, the responsible protease was identified as ADAM10. ADAM10 also was identified as protease responsible for ionomycin-induced shedding of murine and human IL-6R. However, in ADAM10-deficient murine embryonic fibroblasts, compensatory shedding of human IL-6R was mediated by ADAM17, but loss of ADAM10-mediated shedding of murine IL-6R was compensated by an as-yet-unidentified protease. Finally, we identified physiological purinergic P2X7 receptor stimulation as a novel inducer of murine and human IL-6R shedding solely mediated by ADAM10. In conclusion, we describe an unexpected species specificity of ADAM10 and ADAM17 and identified ADAM10 as novel inducible sheddase of IL-6R in mice and humans, which might have consequences for the interpretation of phenotypes from ADAM17- and ADAM10-deficient mice.
Karina Reiss - One of the best experts on this subject based on the ideXlab platform.
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t cell immunoglobulin and mucin domain 2 tim 2 is a target of adam10 mediated ectodomain shedding
FEBS Journal, 2014Co-Authors: Christin Dewitz, Athena Chalaris, Jurgen Scheller, Karina Reiss, Katja Mollerhackbarth, Olga Schweigert, Stefan RosejohnAbstract:T-cell immunoglobulin and mucin domain (TIM)-2 is expressed on activated B cells. Here, we provide evidence that murine TIM-2 is a target of ADAM10-mediated ectodomain shedding, resulting in the generation of a soluble form of TIM-2. We identified ADAM10 but not ADAM17 as the major sheddase of TIM-2, as shown by pharmacological ADAM10 inhibition and with ADAM10-deficient and ADAM17-deficient murine embryonic fibroblasts. Ionomycin-induced or 2′(3′)-O-(4-benzoylbenzoyl) ATP triethylammonium salt-induced shedding of TIM-2 was abrogated by deletion of 10 juxtamembrane amino acids from the stalk region but not by deletion of two further N-terminally located blocks of 10 amino acids, indicating a membrane-proximal cleavage site. TIM-2 lacking the intracellular domain was cleaved after ionomycin or 2′ (3′)-O-(4-benzoylbenzoyl) ATP triethylammonium salt treatment, indicating that this domain was not involved in the regulation of ectodomain shedding. Moreover, TIM-2 shedding was negatively controlled by calmodulin. Shed and soluble TIM-2 interacted with H-ferritin. In summary, we describe TIM-2 as a novel target for ADAM10-mediated ectodomain shedding, and reveal the involvement of ADAM proteases in cellular iron homeostasis.
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unsaturated fatty acids drive disintegrin and metalloproteinase adam dependent cell adhesion proliferation and migration by modulating membrane fluidity
Journal of Biological Chemistry, 2011Co-Authors: Karina Reiss, Isabell Cornelsen, Matthias Husmann, Gerald Gimpl, Sucharit BhakdiAbstract:The disintegrin-metalloproteinases ADAM10 and ADAM17 mediate the release of several cell signaling molecules and cell adhesion molecules such as vascular endothelial cadherin or L-selectin affecting endothelial permeability and leukocyte transmigration. Dysregulation of ADAM activity may contribute to the pathogenesis of vascular diseases, but the mechanisms underlying the control of ADAM functions are still incompletely understood. Atherosclerosis is characterized by lipid plaque formation and local accumulation of unsaturated free fatty acids (FFA). Here, we show that unsaturated FFA increase ADAM-mediated substrate cleavage. We demonstrate that these alterations are not due to genuine changes in enzyme activity, but correlate with changes in membrane fluidity as revealed by measurement of 1,6-diphenyl-1,3,5-hexatriene fluorescence anisotropy and fluorescence recovery after photobleaching analyses. ELISA and immunoblot experiments conducted with granulocytes, endothelial cells, and keratinocytes revealed rapid increase of ectodomain shedding of ADAM10 and ADAM17 substrates upon membrane fluidization. Large amounts of unsaturated FFA may be liberated from cholesteryl esters in LDL that is entrapped in atherosclerotic lesions. Incubation of cells with thus modified LDL resulted in rapid cleavage of ADAM substrates with corresponding functional consequences on cell proliferation, cell migration, and endothelial permeability, events of high significance in atherogenesis. We propose that FFA represent critical regulators of ADAM function that may assume relevance in many biological settings through their influence on mobility of enzyme and substrate in lipid bilayers.
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the a disintegrin and metalloproteases adam10 and ADAM17 novel drug targets with therapeutic potential
European Journal of Cell Biology, 2011Co-Authors: Paul Saftig, Karina ReissAbstract:Proteolytic ectodomain release, a process known as "shedding", has been recognised as a key mechanism for regulating the function of a diversity of cell surface proteins. A Disintegrin And Metalloproteinases (ADAMs) have emerged as the major proteinase family that mediates ectodomain shedding. Dysregulation of ectodomain shedding is associated with autoimmune and cardiovascular diseases, neurodegeneration, infection, inflammation and cancer. Therefore, ADAMs are increasingly regarded as attractive targets for novel therapies. ADAM10 and its close relative ADAM17 (TNF-alpha converting enzyme (TACE)) have been studied in particular in the context of ectodomain shedding and have been demonstrated as key molecules in most of the shedding events characterised to date. Whereas the level of expression of ADAM10 may be of importance in cancer and neurodegenerative disorders, ADAM17 mainly coordinates pro- and anti-inflammatory activities during immune response. Despite the high therapeutical potential of ADAM inhibition, all clinical trials using broad-spectrum metalloprotease inhibitors have failed so far. This review will cover the emerging roles of both ADAM10 and ADAM17 in the regulation of major physiological and developmental pathways and will discuss the suitability of specifically modulating the activities of both proteases as a feasible way to inhibit inflammatory states, cancer and neurodegeneration.
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ADAM17 is regulated by a rapid and reversible mechanism that controls access to its catalytic site
Journal of Cell Science, 2010Co-Authors: Sylvain Le Gall, Paul Saftig, Karina Reiss, Thorsten Maretzky, Priya D Issuree, Xiaoda Niu, Rama Khokha, Daniel Lundell, Carl P. BlobelAbstract:Protein ectodomain shedding is crucial for cell–cell interactions because it controls the bioavailability of soluble tumor necrosis factor-α (TNFα) and ligands of the epidermal growth factor (EGF) receptor, and the release of many other membrane proteins. Various stimuli can rapidly trigger ectodomain shedding, yet much remains to be learned about the identity of the enzymes that respond to these stimuli and the mechanisms underlying their activation. Here, we demonstrate that the membrane-anchored metalloproteinase ADAM17, but not ADAM10, is the sheddase that rapidly responds to the physiological signaling pathways stimulated by thrombin, EGF, lysophosphatidic acid and TNFα. Stimulation of ADAM17 is swift and quickly reversible, and does not depend on removal of its inhibitory pro-domain by pro-protein convertases, or on dissociation of an endogenous inhibitor, TIMP3. Moreover, activation of ADAM17 by physiological stimuli requires its transmembrane domain, but not its cytoplasmic domain, arguing against inside–out signaling via cytoplasmic phosphorylation as the underlying mechanism. Finally, experiments with the tight binding hydroxamate inhibitor DPC333, used here to probe the accessibility of the active site of ADAM17, demonstrate that this inhibitor can quickly bind to ADAM17 in stimulated, but not quiescent cells. These findings support the concept that activation of ADAM17 involves a rapid and reversible exposure of its catalytic site.
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Part-Time α-Secretases: The Functional Biology of ADAM 9, 10 and 17
Current Alzheimer research, 2008Co-Authors: Miriam Deuss, Karina Reiss, Dieter H. HartmannAbstract:Disintegrin metalloproteases of the ADAM family form a large (at present > 40 members in mammals) family of multidomain membrane proteins that in their ectodomain combine a cystein-rich, disintegrin and a zinc metalloprotease domain. Via their metalloprotease domain, ADAMs are often implicated in ectodomain shedding, either to release e.g. growth factors or to initiate further intracellular signalling via regulated intramembrane proteolysis. Mainly based upon overexpression studies in vehicle cells, three of them, ADAMs 9, 10 and 17, have been proposed to act as alpha-secretases for amyloid precursor protein (APP). It is striking thereby that this role has since then remained somewhat ill-defined, as APP processing in ADAM9 deficient neurons is unaltered, and also ADAM10 deficient murine embryonic fibroblasts exhibit at best a highly variable reduction in alpha-secretase activity. However, during the past years, numerous other substrates have been linked to all three sheddases, the cleavage of which in some cases appears to be strikingly more important for the organism than APP processing. Most notably, the perinatally lethal phenotype of ADAM17 knockout mice is dominated by a loss of growth factor shedding, while the even earlier fatal effects of ADAM10 deficiency exhibit key features of disabled Notch signalling and possibly also cadherin processing defects. In this review, we will summarize the published data on the "non-APP" functions of all three ADAMs, the further evaluation of which may be crucial when attempting to treat Alzheimer s Disease by increasing their expression and/or activity. As the knockouts of ADAM10 and ADAM17 are only informative for their roles in (early) development, while a number of recently assigned new substrates play crucial roles in the normal and/or diseased adult organism as well, work on conditional knockout models will be crucial to fully characterize both the full functional portfolio of (candidate) alpha-secretases as well as their clinical relevance, which may go way beyond Alzheimer s Disease.
Gillian Murphy - One of the best experts on this subject based on the ideXlab platform.
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shedding of endogenous interleukin 6 receptor il 6r is governed by a disintegrin and metalloproteinase adam proteases while a full length il 6r isoform localizes to circulating microvesicles
Journal of Biological Chemistry, 2015Co-Authors: Neele Schumacher, Dorte Meyer, Andre Mauermann, Jan Von Der Heyde, Janina Wolf, Jeanette Schwarz, Katharina Knittler, Matthias Michalek, Gillian Murphy, Christoph GarbersAbstract:Generation of the soluble interleukin-6 receptor (sIL-6R) is a prerequisite for pathogenic IL-6 trans-signaling, which constitutes a distinct signaling pathway of the pleiotropic cytokine interleukin-6 (IL-6). Although in vitro experiments using ectopically overexpressed IL-6R and candidate proteases revealed major roles for the metalloproteinases ADAM10 and ADAM17 in IL-6R shedding, the identity of the protease(s) cleaving IL-6R in more physiological settings, or even in vivo, remains unknown. By taking advantage of specific pharmacological inhibitors and primary cells from ADAM-deficient mice we established that endogenous IL-6R of both human and murine origin is shed by ADAM17 in an induced manner, whereas constitutive release of endogenous IL-6R is largely mediated by ADAM10. Although circulating IL-6R levels are altered in various diseases, the origin of blood-borne IL-6R is still poorly understood. It has been shown previously that ADAM17 hypomorphic mice exhibit unaltered levels of serum sIL-6R. Here, by quantification of serum sIL-6R in protease-deficient mice as well as human patients we also excluded ADAM10, ADAM8, neutrophil elastase, cathepsin G, and proteinase 3 from contributing to circulating sIL-6R. Furthermore, we ruled out alternative splicing of the IL-6R mRNA as a potential source of circulating sIL-6R in the mouse. Instead, we found full-length IL-6R on circulating microvesicles, establishing microvesicle release as a novel mechanism for sIL-6R generation.
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Selective inhibition of ADAM12 catalytic activity through engineering of tissue inhibitor of metalloproteinases (TIMP)-2
Biochemical Journal, 2010Co-Authors: Marie Kveiborg, Meng-huee Lee, Jonas Jacobsen, Hideaki Nagase, Ulla M Wewer, Gillian MurphyAbstract:The disintegrin and metalloprotease ADAM12 has important functions in normal physiology as well as in diseases, such as cancer. Little is known about how ADAM12 confers its protumorigenic effect; however, its proteolytic capacity is likely a key component. Thus, selective inhibition of ADAM12 activity may be of great value therapeutically and as an investigative tool to elucidate its mechanisms of actions. We have previously reported the inhibitory profile of tissue inhibitors of metalloproteinases (TIMPs) against ADAM12, demonstrating in addition to TIMP-3, a unique ADAM inhibitory activity of TIMP-2. These findings strongly suggest that it is feasible to design a TIMP mutant selectively inhibiting ADAM12. With this purpose, we characterized the molecular determinants of the ADAM12–TIMP complex formation as compared with known molecular requirements for TIMP-mediated inhibition of ADAM17/TACE. Kinetic analysis using a fluorescent-peptide substrate demonstrated that the molecular interactions of N-terminal domains of TIMPs (N-TIMPs) with ADAM12 and TACE are for the most part comparable, yet revealed striking unique features of TIMP-mediated ADAM12 inhibition. Intriguingly, we found that removal of the AB-loop in N-TIMP-2, which is known to impair its interaction with TACE, resulted in increased affinity to ADAM12. Importantly, using a cell-based epidermal growth factor-shedding assay, we demonstrated for the first time an inhibitory activity of TIMPs against the transmembrane ADAM12-L, verifying the distinctive inhibitory abilities of N-TIMP-2 and engineered N-TIMP-2 mutants in a cellular environment. Together, our findings support the idea that a distinctive ADAM12 inhibitor with future therapeutic potential can be designed.
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The isolated N-terminal domains of TIMP-1 and TIMP-3 are insufficient for ADAM10 inhibition
Biochemical Journal, 2008Co-Authors: Magdalini Rapti, Susan J Atkinson, Meng-huee Lee, Andrew Trim, Marcia Moss, Gillian MurphyAbstract:ADAM10 is a key member of the ADAM family of disintegrin and metalloproteinases which process membrane associated proteins to soluble forms in a process known as 'shedding'. Among the major targets of ADAM10 are Notch, EphrinA2 and CD44. In many cell based studies of shedding the activity of ADAM10 appears to overlap with that of ADAM17 which has a similar active site topology relative to the other proteolytically active ADAMs. The tissue inhibitors of metalloproteinases, TIMPs, have proved useful in the study of ADAM function since TIMP-1 inhibits ADAM10 but not ADAM17, but both enzymes are inhibited by TIMP-3. In this study we show that, in comparison to ADAM17 and the MMPs, the N-terminal domains of TIMPs alone are insufficient for the inhibition of ADAM10.This knowledge could form the basis for the design of directed inhibitors against different metalloproteinases.
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substrate selectivity of epidermal growth factor receptor ligand sheddases and their regulation by phorbol esters and calcium influx
Molecular Biology of the Cell, 2006Co-Authors: Gillian Murphy, Dieter Hartmann, Keisuke Horiuchi, Karina Reiss, Sylvain Le Gall, Marc Schulte, Takafumi Yamaguchi, Yoshiaki Toyama, Paul SaftigAbstract:Signaling via the epidermal growth factor receptor (EGFR), which has critical roles in development and diseases such as cancer, is regulated by proteolytic shedding of its membrane-tethered ligands. Sheddases for EGFR-ligands are therefore key signaling switches in the EGFR pathway. Here, we determined which ADAMs (a disintegrin and metalloprotease) can shed various EGFR-ligands, and we analyzed the regulation of EGFR-ligand shedding by two commonly used stimuli, phorbol esters and calcium influx. Phorbol esters predominantly activate ADAM17, thereby triggering a burst of shedding of EGFR-ligands from a late secretory pathway compartment. Calcium influx stimulates ADAM10, requiring its cytoplasmic domain. However, calcium influx-stimulated shedding of transforming growth factor alpha and amphiregulin does not require ADAM17, even though ADAM17 is essential for phorbol ester-stimulated shedding of these EGFR-ligands. This study provides new insight into the machinery responsible for EGFR-ligand release and thus EGFR signaling and demonstrates that dysregulated EGFR-ligand shedding may be caused by increased expression of constitutively active sheddases or activation of different sheddases by distinct stimuli.
