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Thomas R, Yang X. Semaphorins in immune cell function, inflammatory and infectious diseases. CURRENT RESEARCH IN IMMUNOLOGY 2023; 4:100060. [PMID: 37645659 PMCID: PMC10461194 DOI: 10.1016/j.crimmu.2023.100060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 05/08/2023] [Accepted: 05/14/2023] [Indexed: 08/31/2023] Open
Abstract
The Semaphorin family is a group of proteins studied broadly for their functions in nervous systems. They consist of eight subfamilies ubiquitously expressed in vertebrates, invertebrates, and viruses and exist in membrane-bound or secreted forms. Emerging evidence indicates the relevance of semaphorins outside the nervous system, including angiogenesis, cardiogenesis, osteoclastogenesis, tumour progression, and, more recently, the immune system. This review provides a broad overview of current knowledge on the role of semaphorins in the immune system, particularly its involvement in inflammatory and infectious diseases, including chlamydial infections.
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Affiliation(s)
- Rony Thomas
- Department of Immunology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Xi Yang
- Department of Immunology, University of Manitoba, Winnipeg, Manitoba, Canada
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Yang R, Meyer AS, Droujinine IA, Udeshi ND, Hu Y, Guo J, McMahon JA, Carey DK, Xu C, Fang Q, Sha J, Qin S, Rocco D, Wohlschlegel J, Ting AY, Carr SA, Perrimon N, McMahon AP. A genetic model for in vivo proximity labelling of the mammalian secretome. Open Biol 2022; 12:220149. [PMID: 35946312 PMCID: PMC9364151 DOI: 10.1098/rsob.220149] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Organ functions are highly specialized and interdependent. Secreted factors regulate organ development and mediate homeostasis through serum trafficking and inter-organ communication. Enzyme-catalysed proximity labelling enables the identification of proteins within a specific cellular compartment. Here, we report a BirA*G3 mouse strain that enables CRE-dependent promiscuous biotinylation of proteins trafficking through the endoplasmic reticulum. When broadly activated throughout the mouse, widespread labelling of proteins was observed within the secretory pathway. Streptavidin affinity purification and peptide mapping by quantitative mass spectrometry (MS) proteomics revealed organ-specific secretory profiles and serum trafficking. As expected, secretory proteomes were highly enriched for signal peptide-containing proteins, highlighting both conventional and non-conventional secretory processes, and ectodomain shedding. Lower-abundance proteins with hormone-like properties were recovered and validated using orthogonal approaches. Hepatocyte-specific activation of BirA*G3 highlighted liver-specific biotinylated secretome profiles. The BirA*G3 mouse model demonstrates enhanced labelling efficiency and tissue specificity over viral transduction approaches and will facilitate a deeper understanding of secretory protein interplay in development, and in healthy and diseased adult states.
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Affiliation(s)
- Rui Yang
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA, USA,Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA, USA
| | - Amanda S. Meyer
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA, USA,Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA, USA
| | | | | | - Yanhui Hu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Jinjin Guo
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA, USA,Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA, USA
| | - Jill A. McMahon
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA, USA,Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA, USA
| | | | - Charles Xu
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Qiao Fang
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada, M5S 3E1
| | - Jihui Sha
- Department of Biological Chemistry, Geffen School of Medicine at UCLA, University of California, Los Angeles, Los Angeles, CA, USA
| | - Shishang Qin
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing, People's Republic of China
| | - David Rocco
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - James Wohlschlegel
- Department of Biological Chemistry, Geffen School of Medicine at UCLA, University of California, Los Angeles, Los Angeles, CA, USA
| | - Alice Y. Ting
- Chan Zuckerberg Biohub, San Francisco, CA, USA,Departments of Genetics, Biology, and Chemistry, Stanford University, Stanford, CA, USA
| | | | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA,Howard Hughes Medical Institute, Boston, MA, USA
| | - Andrew P. McMahon
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA, USA,Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA, USA
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Constitutive and Regulated Shedding of Soluble FGF Receptors Releases Biologically Active Inhibitors of FGF-2. Int J Mol Sci 2021; 22:ijms22052712. [PMID: 33800200 PMCID: PMC7962449 DOI: 10.3390/ijms22052712] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/22/2021] [Accepted: 03/02/2021] [Indexed: 12/03/2022] Open
Abstract
The identification of soluble fibroblast growth factor (FGF) receptors in blood and the extracellular matrix has led to the prediction that these proteins modulate the diverse biological activities of the FGF family of ligands in vivo. A recent structural characterization of the soluble FGF receptors revealed that they are primarily generated by proteolytic cleavage of the FGFR-1 ectodomain. Efforts to examine their biological properties are now focused on understanding the functional consequences of FGFR-1 ectodomain shedding and how the shedding event is regulated. We have purified an FGFR-1 ectodomain that is constitutively cleaved from the full-length FGFR-1(IIIc) receptor and released into conditioned media. This shed receptor binds FGF-2; inhibits FGF-2-induced cellular proliferation; and competes with high affinity, cell surface FGF receptors for ligand binding. FGFR-1 ectodomain shedding downregulates the number of high affinity receptors from the cell surface. The shedding mechanism is regulated by ligand binding and by activators of PKC, and the two signaling pathways appear to be independent of each other. Deletions and substitutions at the proposed cleavage site of FGFR-1 do not prevent ectodomain shedding. Broad spectrum inhibitors of matrix metalloproteases decrease FGFR-1 ectodomain shedding, suggesting that the enzyme responsible for constitutive, ligand-activated, and protein kinase C-activated shedding is a matrix metalloprotease. In summary, shedding of the FGFR-1 ectodomain is a highly regulated event, sharing many features with a common system that governs the release of diverse membrane proteins from the cell surface. Most importantly, the FGFR ectodomains are biologically active after shedding and are capable of functioning as inhibitors of FGF-2.
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Esch A, Masiarz A, Mossner S, Moll JM, Grötzinger J, Schröder J, Scheller J, Floss DM. Deciphering site 3 interactions of interleukin 12 and interleukin 23 with their cognate murine and human receptors. J Biol Chem 2020; 295:10478-10492. [PMID: 32518162 DOI: 10.1074/jbc.ra120.013935] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/03/2020] [Indexed: 01/04/2023] Open
Abstract
Interleukin (IL)-12 and IL-23 belong to the IL-12 type family and are composite cytokines, consisting of the common β subunit p40 and the specific cytokine α subunit p35 and p19, respectively. IL-12 signals via the IL-12Rβ1·IL-12Rβ2 receptor complex, and IL-23 uses also IL-12Rβ1 but engages IL-23R as second receptor. Importantly, binding of IL-12 and IL-23 to IL-12Rβ1 is mediated by p40, and binding to IL-12Rβ2 and IL-23R is mediated by p35 and p19, respectively. Previously, we have identified a W157A substitution at site 3 of murine IL-23p19 that abrogates binding to murine IL-23R. Here, we demonstrate that the analogous Y185R site 3 substitution in murine and Y189R site 3 substitution in human IL-12p35 abolishes binding to IL-12Rβ2 in a cross-species manner. Although Trp157 is conserved between murine and human IL-23p19 (Trp156 in the human ortholog), the site 3 W156A substitution in hIL-23p19 did not affect signaling of cells expressing human IL-12Rβ1 and IL-23R, suggesting that the interface of murine IL-23p19 required for binding to IL-23R is different from that in the human ortholog. Hence, we introduced additional hIL-23p19 substitutions within its binding interface to hIL-23R and found that the combined site 3 substitutions of W156A and L160E, which become buried at the complex interface, disrupt binding of hIL-23p19 to hIL-23R. In summary, we have identified substitutions in IL-12p35 and IL-23p19 that disrupt binding to their cognate receptors IL-12Rβ2 and IL-23R in a murine/human cross-species manner.
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Affiliation(s)
- Alessandra Esch
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Anna Masiarz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Sofie Mossner
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Jens M Moll
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Joachim Grötzinger
- Institute of Biochemistry, Medical Faculty, Christian Albrechts University, Kiel, Germany
| | - Jutta Schröder
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Doreen M Floss
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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Synthetic Deletion of the Interleukin 23 Receptor (IL-23R) Stalk Region Led to Autonomous IL-23R Homodimerization and Activation. Mol Cell Biol 2017. [PMID: 28630278 DOI: 10.1128/mcb.00014-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Interleukin 23 (IL-23) regulates the development of TH17 cells, which are important for antimicrobial and antifungal responses and autoimmune and chronic inflammatory diseases. IL-23-induced Jak/STAT signaling is mediated via the heterodimeric IL-23 receptor (IL-23R)-IL-12 receptor β1 (IL-12Rβ1) complex. The typical signal-transducing receptor of the IL-6/IL-12 family contains three extracellular-membrane-proximal fibronectin type III (FNIII) domains, which are not involved in cytokine binding but are mandatory for signal transduction. In place of FNIII-type domains, IL-23R has a structurally undefined stalk. We hypothesized that the IL-23R stalk acts as a spacer to position the cytokine binding domains at a defined distance from the plasma membrane to enable signal transduction. Minor deletions of the murine, but not of the human, IL-23R stalk resulted in unresponsiveness to IL-23. Complete deletion of the human IL-23R stalk and the extended murine IL-23R stalk, including a 20-amino-acid-long duplication of domain 3, however, induced ligand-independent, autonomous receptor activation, as determined by STAT3 phosphorylation and cell proliferation. Ligand-independent, autonomous activity was caused by IL-23R homodimers and was independent of IL-12Rβ1. Our data show that deletion of the stalk results in biologically active IL-23R homodimers, thereby creating an as-yet-undescribed receptor complex of the IL-6/IL-12 cytokine family.
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Semaphorin 7A as a potential immune regulator and promising therapeutic target in rheumatoid arthritis. Arthritis Res Ther 2017; 19:10. [PMID: 28109308 PMCID: PMC5251212 DOI: 10.1186/s13075-016-1217-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 12/30/2016] [Indexed: 12/23/2022] Open
Abstract
Background Semaphorin 7A (Sema7A) is expressed by several different classes of lymphoid and myeloid cells and is a potent immunomodulator. We examined the role of Sema7A in modulating cellular immune responses and to provide experimental data validating the therapeutic potential of Sema7A in rheumatoid arthritis (RA). Methods Soluble Sema7A (sSema7A) levels in the serum and synovial fluid from patients with RA or osteoarthritis, as well as cytokine secretions, were analyzed with an enzyme-linked immunosorbent assay. The cell surface levels and transcripts of Sema7A were evaluated in T cells and monocytes from patients with RA. The effect of Sema7A on the functions of primary T cells isolated from the peripheral blood of healthy donors was observed. Detection of the activation of the signal mediator focal adhesion kinase was performed by Western blotting. Shedding of sSema7A was evaluated in monocytes. The introduction of anti-Sema7A antibody to mice with collagen-induced arthritis (CIA) was observed in vivo. Results Upregulation of sSema7A levels in both the serum and synovial fluid of patients with RA was correlated with disease activity markers. sSema7A markedly increased Th1/Th17 cytokine secretion and induced evident upregulation of T-bet and retinoic acid receptor-related orphan nuclear receptor γt levels in T cells. Cell surface Sema7A was cleaved by a disintegrin and metalloprotease 17 (ADAM17) in monocytes. Interleukin-6 and tumor necrosis factor-α stimulated ADAM17 secretion in synovial macrophages. Blocking of β1-integrin abrogated the Sema7A-mediated cytokine secretion. Treatment with an anti-Sema7A antibody significantly attenuated CIA. Conclusions These findings indicate that Sema7A as a potent activator of T cells and monocytes in the immune response contributes to the inflammation and progression of RA, suggesting its therapeutic potential in the treatment of RA.
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Proteolytic Origin of the Soluble Human IL-6R In Vivo and a Decisive Role of N-Glycosylation. PLoS Biol 2017; 15:e2000080. [PMID: 28060820 PMCID: PMC5218472 DOI: 10.1371/journal.pbio.2000080] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 12/08/2016] [Indexed: 12/15/2022] Open
Abstract
Signaling of the cytokine interleukin-6 (IL-6) via its soluble IL-6 receptor (sIL-6R) is responsible for the proinflammatory properties of IL-6 and constitutes an attractive therapeutic target, but how the sIL-6R is generated in vivo remains largely unclear. Here, we use liquid chromatography–mass spectrometry to identify an sIL-6R form in human serum that originates from proteolytic cleavage, map its cleavage site between Pro-355 and Val-356, and determine the occupancy of all O- and N-glycosylation sites of the human sIL-6R. The metalloprotease a disintegrin and metalloproteinase 17 (ADAM17) uses this cleavage site in vitro, and mutation of Val-356 is sufficient to completely abrogate IL-6R proteolysis. N- and O-glycosylation were dispensable for signaling of the IL-6R, but proteolysis was orchestrated by an N- and O-glycosylated sequon near the cleavage site and an N-glycan exosite in domain D1. Proteolysis of an IL-6R completely devoid of glycans is significantly impaired. Thus, glycosylation is an important regulator for sIL-6R generation. Interleukin-6 (IL-6) is a cytokine secreted by our body upon infection or trauma to stimulate the immune system response. IL-6 is partially responsible for fever and triggers inflammation in many diseases. It activates its target cells via the membrane-bound IL-6 receptor (IL-6R), and soluble forms of this receptor (sIL-6R) are present in high amounts in the serum of healthy individuals and mediate the inflammatory response in all cells of the human body. However, it remains unclear how the soluble form of this cytokine is generated in humans. In this study, we isolate sIL-6R from human serum and show that the majority is produced via cleavage of the membrane-bound IL-6R by a protease. We identify the exact cleavage site and find that it is identical to a cleavage site used by the metalloprotease ADAM17. We further show that glycosylation, a post-transcriptional modification, is dispensable for the transport and biological function of IL-6R and map the occupancy of all O- and N-glycosylation sites. However, we find that only a single N-glycan is critically involved in the regulation of proteolysis by ADAM17 and conclude that glycosylation is an important regulator for sIL-6R generation.
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Floss DM, Klöcker T, Schröder J, Lamertz L, Mrotzek S, Strobl B, Hermanns H, Scheller J. Defining the functional binding sites of interleukin 12 receptor β1 and interleukin 23 receptor to Janus kinases. Mol Biol Cell 2016; 27:2301-16. [PMID: 27193299 PMCID: PMC4945146 DOI: 10.1091/mbc.e14-12-1645] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 05/13/2016] [Indexed: 01/14/2023] Open
Abstract
Stimulation of cells with the IL-12–type cytokine IL-12 or IL-23 results in activation of receptor-associated Janus kinases (Jak) and phosphorylation of STAT proteins in target cells. Functional association of IL 12Rβ1 with tyrosine kinase 2 and IL-23R with Jak2 is mandatory for IL-12 and/or IL-23 signaling. The interleukin (IL)-12–type cytokines IL-12 and IL-23 are involved in T-helper (Th) 1 and Th17 immunity, respectively. They share the IL-12 receptor β1 (IL-12Rβ1) as one component of their receptor signaling complexes, with IL-12Rβ2 as second receptor for IL-12 and IL-23R for IL-23 signal transduction. Stimulation with IL-12 and IL-23 results in activation of receptor-associated Janus kinases (Jak) and phosphorylation of STAT proteins in target cells. The Janus kinase tyrosine kinase (Tyk) 2 associates with IL-12Rβ1, whereas Jak2 binds to IL-23R and also to IL-12Rβ2. Receptor association of Jak2 is mediated by Box1 and Box2 motifs located within the intracellular domain of the receptor chains. Here we define the Box1 and Box2 motifs in IL-12Rβ1 and an unusual Jak2-binding site in IL-23R by the use of deletion and site-directed mutagenesis. Our data show that nonfunctional box motifs abolish IL-12– and IL-23–induced STAT3 phosphorylation and cytokine-dependent proliferation of Ba/F3 cells. Coimmunoprecipitation of Tyk2 by IL-12Rβ1 and Jak2 by IL‑23R supported these findings. In addition, our data demonstrate that association of Jak2 with IL-23R is mandatory for IL-12 and/or IL-23 signaling, whereas Tyk2 seems to be dispensable.
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Affiliation(s)
- Doreen M Floss
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
| | - Tobias Klöcker
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
| | - Jutta Schröder
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
| | - Larissa Lamertz
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
| | - Simone Mrotzek
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
| | - Birgit Strobl
- Institute of Animal Breeding and Genetics/Biomodels Austria, University of Veterinary Medicine, A-1210 Vienna, Austria
| | - Heike Hermanns
- Medical Clinic II, Division of Hepatology, University Hospital Würzburg, D-97080 Würzburg, Germany
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, D-40225 Düsseldorf, Germany
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Schröder J, Moll JM, Baran P, Grötzinger J, Scheller J, Floss DM. Non-canonical interleukin 23 receptor complex assembly: p40 protein recruits interleukin 12 receptor β1 via site II and induces p19/interleukin 23 receptor interaction via site III. J Biol Chem 2014; 290:359-70. [PMID: 25371211 DOI: 10.1074/jbc.m114.617597] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
IL-23, composed of the cytokine subunit p19 and the soluble α receptor subunit p40, binds to a receptor complex consisting of the IL-23 receptor (IL-23R) and the IL-12 receptor β1 (IL-12Rβ1). Complex formation was hypothesized to follow the "site I-II-III" architectural paradigm, with site I of p19 being required for binding to p40, whereas sites II and III of p19 mediate binding to IL-12Rβ1 and IL-23R, respectively. Here we show that the binding mode of p19 to p40 and of p19 to IL-23R follow the canonical site I and III paradigm but that interaction of IL-23 to IL-12Rβ1 is independent of site II in p19. Instead, binding of IL-23 to the cytokine binding module of IL-12Rβ1 is mediated by domains 1 and 2 of p40 via corresponding site II amino acids of IL-12Rβ1. Moreover, domains 2 and 3 of p40 were sufficient for complex formation with p19 and to induce binding of p19 to IL-23R. The Fc-tagged fusion protein of p40_D2D3/p19 did, however, not act as a competitive IL-23 antagonist but, at higher concentrations, induced proliferation via IL-23R but independent of IL-12Rβ1. On the basis of our experimental validation, we propose a non-canonical topology of the IL-23·IL-23R·IL-12Rβ1 complex. Furthermore, our data help to explain why p40 is an antagonist of IL-23 and IL-12 signaling and show that site II of p19 is dispensable for IL-23 signaling.
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Affiliation(s)
- Jutta Schröder
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany and
| | - Jens M Moll
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany and
| | - Paul Baran
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany and
| | - Joachim Grötzinger
- the Institute of Biochemistry, Medical Faculty, Christian Albrechts University, 24098 Kiel, Germany
| | - Jürgen Scheller
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany and
| | - Doreen M Floss
- From the Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany and
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Chen Q, Zhang W, Ran H, Feng L, Yan H, Mu X, Han Y, Liu W, Xia G, Wang C. PKCδ and θ possibly mediate FSH-induced mouse oocyte maturation via NOX-ROS-TACE cascade signaling pathway. PLoS One 2014; 9:e111423. [PMID: 25350560 PMCID: PMC4211700 DOI: 10.1371/journal.pone.0111423] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 09/25/2014] [Indexed: 01/28/2023] Open
Abstract
In mammals, gonadotropins stimulate oocyte maturation via the epidermal growth factor (EGF) network, and the protein kinase C (PKC) signaling pathway mediates this process. Tumor necrosis factor-α converting enzyme (TACE) is an important protein responding to PKC activation. However, the detailed signaling cascade between PKC and TACE in follicle-stimulating hormone (FSH)-induced oocyte maturation in vitro remains unclear. In this study, we found that rottlerin (mallotoxin, MTX), the inhibitor of PKC δ and θ, blocked FSH-induced maturation of mouse cumulus-oocyte complexes (COCs) in vitro. We further clarified the relationship between two molecules downstream of PKC δ and θ and TACE in COCs: nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) and its products, reactive oxygen species (ROS). We proved that the respective inhibitors of NOX, ROS and TACE could block FSH-stimulated oocyte maturation dose-dependently, but these inhibitory effects could be reversed partially by amphiregulin (Areg), an EGF family member. Notably, inhibition of PKC δ and θ prevented FSH-induced translocation of two cytosolic components of NOX, p47phox and p67phox, to the plasma membrane in cumulus cells. Moreover, FSH-induced TACE activity in cumulus cells was decreased markedly by inhibition of NOX and ROS. In conclusion, PKC δ and θ possibly mediate FSH-induced meiotic resumption in mouse COCs via NOX-ROS-TACE signaling pathway.
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Affiliation(s)
- Qian Chen
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Wenqiang Zhang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Hao Ran
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Lizhao Feng
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Hao Yan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Xinyi Mu
- Department of histology and embryology, Chongqing medical university, Chongqing, People’s Republic of China
| | - Yingying Han
- College of biological sciences and technology, Beijing Forestry University, Beijing, People’s Republic of China
| | - Wei Liu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Guoliang Xia
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
| | - Chao Wang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People’s Republic of China
- * E-mail:
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Wolf J, Rose-John S, Garbers C. Interleukin-6 and its receptors: a highly regulated and dynamic system. Cytokine 2014; 70:11-20. [PMID: 24986424 DOI: 10.1016/j.cyto.2014.05.024] [Citation(s) in RCA: 317] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 05/24/2014] [Indexed: 01/13/2023]
Abstract
Interleukin-6 (IL-6) is a multifunctional cytokine with well-defined pro- and anti-inflammatory properties. Although only small amounts in the picogram range can be detected in healthy humans, IL-6 expression is highly and transiently up-regulated in nearly all pathophysiological states. IL-6 induces intracellular signaling pathways after binding to its membrane-bound receptor (IL-6R), which is only expressed on hepatocytes and certain subpopulations of leukocytes (classic signaling). Transduction of the signal is mediated by the membrane-bound β-receptor glycoprotein 130 (gp130). In a second pathway, named trans-signaling, IL-6 binds to soluble forms of the IL-6R (sIL-6R), and this agonistic IL-6/sIL-6R complexes can in principle activate all cells due to the uniform expression of gp130. Importantly, several soluble forms of gp130 (sgp130) are found in the human blood, which are considered to be the natural inhibitors of IL-6 trans-signaling. Most pro-inflammatory roles of IL-6 have been attributed to the trans-signaling pathway, whereas anti-inflammatory and regenerative signaling, including the anti-bacterial acute phase response of the liver, is mediated by IL-6 classic signaling. In this simplistic view, only a minority of cell types expresses the IL-6R and is therefore responsive for IL-6 classic signaling, whereas gp130 is ubiquitously expressed throughout the human body. However, several reports point towards a much more complex situation. A plethora of factors, including proteases, cytokines, chemical drugs, and intracellular signaling pathways, are able to modulate the cellular expression of the membrane-bound and soluble forms of IL-6R and gp130. In this review, we summarize current knowledge of regulatory mechanisms that control and regulate the dynamic expression of IL-6 and its two receptors.
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Affiliation(s)
- Janina Wolf
- Institute of Biochemistry, Kiel University, Olshausenstrasse 40, Kiel, Germany
| | - Stefan Rose-John
- Institute of Biochemistry, Kiel University, Olshausenstrasse 40, Kiel, Germany.
| | - Christoph Garbers
- Institute of Biochemistry, Kiel University, Olshausenstrasse 40, Kiel, Germany.
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Zhang C, Zheng L, Nurnberg J, Vacari BM, Zhou J, Wang Y. Cleavage of pro-tumor necrosis factor alpha by ADAM metallopeptidase domain 17: a fluorescence-based protease assay cleaves its natural protein substrate. Anal Biochem 2013; 445:14-9. [PMID: 24096196 DOI: 10.1016/j.ab.2013.09.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/19/2013] [Accepted: 09/23/2013] [Indexed: 12/20/2022]
Abstract
A fluorescence-based Adam 17 activity assay that cleaves pro-tumor necrosis factor alpha (pro-TNFα) protein substrate has been developed. The key to the assay was site-specific labeling of a fluorescence dye to the N-terminal end of the substrate protein, which was achieved by the protein ligation method. The protease cleavage reaction was monitored by fluorescence polarization. This homogeneous assay allows reaction progress to be recorded kinetically in real time. The results were validated by gel electrophoresis and high-performance liquid chromatography. As expected, the reaction could be inhibited by an ADAM metallopeptidase domain 17 (Adam 17) active site inhibitor. Interestingly, the reaction rate of pro-TNFα cleavage by Adam 17 was also reduced by a small molecule binding to pro-TNFα protein, the substrate of the reaction. This small molecule, however, did not affect the activity of Adam 17 to its peptide substrate. These results demonstrate that this natural protein substrate-based fluorescent assay was able to identify the inhibitor binding to substrate protein in addition to that binding to the protease itself. Comparing this protein substrate with a short peptide substrate, the activity of Adam 17 showed different pH profiles. With pro-TNFα the optimal pH was approximately 7.4, whereas with the peptide substrate the optimal pH was higher than 9.0.
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13
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Floss DM, Mrotzek S, Klöcker T, Schröder J, Grötzinger J, Rose-John S, Scheller J. Identification of canonical tyrosine-dependent and non-canonical tyrosine-independent STAT3 activation sites in the intracellular domain of the interleukin 23 receptor. J Biol Chem 2013; 288:19386-400. [PMID: 23673666 DOI: 10.1074/jbc.m112.432153] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Signaling of interleukin 23 (IL-23) via the IL-23 receptor (IL-23R) and the shared IL-12 receptor β1 (IL-12Rβ1) controls innate and adaptive immune responses and is involved in the differentiation and expansion of IL-17-producing CD4(+) T helper (TH17) cells. Activation of signal transducer and activator of transcription 3 (STAT3) appears to be the major signaling pathway of IL-23, and STAT binding sites were predicted in the IL-23R but not in the IL-12Rβ1 chain. Using site-directed mutagenesis and deletion variants of the murine and human IL-23R, we showed that the predicted STAT binding sites (pYXXQ; including Tyr-504 and Tyr-626 in murine IL-23R and Tyr-484 and Tyr-611 in human IL-23R) mediated STAT3 activation. Furthermore, we identified two uncommon STAT3 binding/activation sites within the murine IL-23R. First, the murine IL-23R carried the Y(542)PNFQ sequence, which acts as an unusual Src homology 2 (SH2) domain-binding protein activation site of STAT3. Second, we identified a non-canonical, phosphotyrosine-independent STAT3 activation motif within the IL-23R. A third predicted site, Tyr-416 in murine and Tyr-397 in human IL-23R, is involved in the activation of PI3K/Akt and the MAPK pathway leading to STAT3-independent proliferation of Ba/F3 cells upon stimulation with IL-23. In contrast to IL-6-induced short term STAT3 phosphorylation, cellular activation by IL-23 resulted in a slower but long term STAT3 phosphorylation, indicating that the IL-23R might not be a major target of negative feedback inhibition by suppressor of cytokine signaling (SOCS) proteins. In summary, we characterized IL-23-dependent signal transduction with a focus on STAT3 phosphorylation and identified canonical tyrosine-dependent and non-canonical tyrosine-independent STAT3 activation sites in the IL-23R.
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Affiliation(s)
- Doreen M Floss
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf 40225, Germany
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Baran P, Nitz R, Grötzinger J, Scheller J, Garbers C. Minimal interleukin 6 (IL-6) receptor stalk composition for IL-6 receptor shedding and IL-6 classic signaling. J Biol Chem 2013; 288:14756-68. [PMID: 23564454 DOI: 10.1074/jbc.m113.466169] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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 Å. 22 amino acid residues, however, span maximally 83.6 Å (3.8 Å/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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Affiliation(s)
- Paul Baran
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany
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15
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Jagged-1 juxtamembrane region: biochemical characterization and cleavage by ADAM17 (TACE) catalytic domain. Biochem Biophys Res Commun 2013; 432:666-71. [PMID: 23416080 DOI: 10.1016/j.bbrc.2013.02.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 02/06/2013] [Indexed: 12/19/2022]
Abstract
Ectodomain shedding of membrane receptors and ligands carried out by ADAMs (A disintegrin and metalloprotease) plays a major role in several signaling pathways, including Notch. The grounds of substrate recognition, however, are poorly understood. We demonstrate that a recombinant protein corresponding to the juxtamembrane region of Jagged-1, one of the Notch ligands, behaves as a structured module and is cleaved by ADAM17 catalytic domain at E1054. A short synthetic peptide is cleaved at the same site but at a much higher rate, implying that the structure of the cleavage site in the native protein is a key determinant for substrate recognition. We also show that an Alagille syndrome-associated mutation near E1054 increases the cleavage rate, which suggests that this mutation may lead to an unbalance in Notch signaling due to a higher level of Jagged-1 shedding.
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Abstract
Interleukin-6 (IL-6) is a cytokine which is involved in many inflammatory processes and in the development of cancer. In addition, IL-6 has been shown to be important for the induction of hepatic acute-phase proteins, for the regeneration of the liver and for the stimulation of B-cells. IL-6 binds to a transmembrane IL-6 receptor (IL-6R), which is present on hepatocytes and some leukocytes. The complex of IL-6 and IL-6R associates with a second protein, gp130, which is expressed on all cells of the body. Since neither IL-6 nor IL-6R has a measurable affinity for gp130, cells, which do not express IL-6R, are not responsive to the cytokine IL-6. It could be shown, however, that a naturally occurring soluble IL-6R (sIL-6R) in complex with IL-6 can bind to gp130 on cells with no IL-6R expression. Therefore, cells shedding the sIL-6R render cells, which only express gp130, responsive to the cytokine. This process has been called trans-signaling. In the present chapter, we summarize the known activities of IL-6 with a special emphasis on regenerative activities, which often depend on the sIL-6R. A designer cytokine called Hyper-IL-6, which is a fusion protein of IL-6 and the sIL-6R, can mimic IL-6 trans-signaling responses in vitro and in vivo with considerably higher efficacy than the combination of the natural proteins IL-6 and sIL-6R. We present recent examples from animal models in which the therapeutic potential of Hyper-IL-6 has been evaluated. We propose that Hyper-IL-6 can be used to induce potent regeneration responses in liver, kidney, and other tissues and therefore will be a novel therapeutic approach in regenerative medicine.
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Affiliation(s)
- Eithan Galun
- Goldyne Savad Inst. of Gene Therapy, Hadassah Hebrew University Hospital, Jerusalem, Israel
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17
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Evans SF, Irmady K, Ostrow K, Kim T, Nykjaer A, Saftig P, Blobel C, Hempstead BL. Neuronal brain-derived neurotrophic factor is synthesized in excess, with levels regulated by sortilin-mediated trafficking and lysosomal degradation. J Biol Chem 2011; 286:29556-67. [PMID: 21730062 DOI: 10.1074/jbc.m111.219675] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) regulates neuronal differentiation, synaptic plasticity, and morphology, and modest changes in BDNF levels results in complex behavioral phenotypes. BDNF levels and intracellular localization in neurons are regulated by multiple mechanisms, including use of distinct promoters, mRNA and protein transport, and regulated cleavage of proBDNF to mature BDNF. Sortilin is an intracellular chaperone that binds to the prodomain of BDNF to traffic it to the regulated secretory pathway. However, sortilin binds to numerous ligands and plays a major role in mannose 6-phosphate receptor-independent transport of lysosomal hydrolases utilizing motifs in the intracellular domain that mediate trafficking from the Golgi and late endosomes. Sortilin is modified by ectodomain shedding, although the biological implications of this are not known. Here we demonstrate that ADAM10 is the preferred protease to cleave sortilin in the extracellular stalk region, to release the ligand binding sortilin ectodomain from the transmembrane and cytoplasmic domains. We identify sortilin shedding at the cell surface and in an intracellular compartment. Both sortilin and BDNF are trafficked to and degraded by the lysosome in neurons, and this is dependent upon the sortilin cytoplasmic tail. Indeed, expression of the sortilin ectodomain, which corresponds to the domain released after shedding, impairs lysosomal targeting and degradation of BDNF. These findings characterize the regulation of sortilin shedding and identify a novel mechanism by which sortilin ectodomain shedding acts as a regulatory switch for delivery of BDNF to the secretory pathway or to the lysosome, thus modulating the bioavailability of endogenous BDNF.
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Affiliation(s)
- Sarah Felice Evans
- Graduate Program in Neuroscience, Weill Medical College of Cornell University, New York, New York 10065, USA
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18
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Overexpression of a splice variant of oncostatin M receptor beta in human esophageal squamous carcinoma. Cell Oncol (Dordr) 2011; 34:177-87. [DOI: 10.1007/s13402-011-0011-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2011] [Indexed: 10/18/2022] Open
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Loppnow H, Buerke M, Werdan K, Rose-John S. Contribution of vascular cell-derived cytokines to innate and inflammatory pathways in atherogenesis. J Cell Mol Med 2011; 15:484-500. [PMID: 21199323 PMCID: PMC3922371 DOI: 10.1111/j.1582-4934.2010.01245.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Accepted: 12/21/2010] [Indexed: 01/22/2023] Open
Abstract
Inflammation is a central element of atherogenesis. Innate pathways contribute to vascular inflammation. However, the initial molecular process(es) starting atherogenesis remain elusive. The various risk factors, represented by particular compounds (activators), may cause altered cellular functions in the endothelium (e.g. vascular endothelial cell activation or -dysfunction), in invading cells (e.g. inflammatory mediator production) or in local vessel wall cells (e.g. inflammatory mediators, migration), thereby triggering the innate inflammatory process. The cellular components of innate immunology include granulocytes, natural killer cells and monocytes. Among the molecular innate constituents are innate molecules, such as the toll-like receptors or innate cytokines. Interleukin-1 (IL-1) and IL-6 are among the innate cytokines. Cytokines are potent activators of a great number of cellular functions relevant to maintain or commove homeostasis of the vessel wall. Within the vessel wall, vascular smooth muscle cells (SMCs) can significantly contribute to the cytokine-dependent inflammatory network by: (i) production of cytokines, (ii) response to cytokines and (iii) cytokine-mediated interaction with invading leucocytes. The cytokines IL-1 and IL-6 are involved in SMC-leucocyte interaction. The IL-6 effects are proposed to be mediated by trans-signalling. Dysregulated cellular functions resulting from dysregulated cytokine production may be the cause of cell accumulation, subsequent low-density lipoprotein accumulation and deposition of extracellular matrix (ECM). The deposition of ECM, increased accumulation of leucocytes and altered levels of inflammatory mediators may constitute an 'innate-immunovascular-memory' resulting in an ever-growing response to anew invasion. Thus, SMC-fostered inflammation, promoted by invading innate cells, may be a potent component for development and acceleration of atherosclerosis.
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Affiliation(s)
- Harald Loppnow
- Department of Internal Medicine III, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.
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20
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Mück C, Herndler-Brandstetter D, Micutkova L, Grubeck-Loebenstein B, Jansen-Dürr P. Two functionally distinct isoforms of TL1A (TNFSF15) generated by differential ectodomain shedding. J Gerontol A Biol Sci Med Sci 2010; 65:1165-80. [PMID: 20675618 PMCID: PMC2954241 DOI: 10.1093/gerona/glq129] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tumor necrosis factor–like cytokine 1A (TL1A) is expressed in endothelial cells and contributes to T-cell activation, via an extracellular fragment TL1AL72-L251, generated by ectodomain shedding. Fragments of TL1A, referred to as vascular endothelial growth inhibitor, were found to induce growth arrest and apoptosis in endothelial cells; however, the underlying mechanisms remained obscure. Here, we show that full-length TL1A is the major detectable gene product in both human umbilical vein endothelial cells and circulating endothelial progenitor cells. TL1A expression was significantly enhanced in senescent circulating endothelial progenitor cells, and knockdown of TL1A partially reverted senescence. TL1A overexpression induced premature senescence in both circulating endothelial progenitor cells and human umbilical vein endothelial cells. We also identified a novel extracellular fragment of TL1A, TL1AV84-L251, resulting from differential ectodomain shedding, which induced growth arrest and apoptosis in human umbilical vein endothelial cells. These findings suggest that TL1A is involved in the regulation of endothelial cell senescence, via a novel fragment produced by differential ectodomain shedding.
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Affiliation(s)
- Christoph Mück
- Department of Molecular and Cell Biology, Institute for Biomedical Aging Research, Austrian Academy of Sciences, Innsbruck, Austria
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21
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Knüpfer H, Preiss R. Serum interleukin-6 levels in colorectal cancer patients--a summary of published results. Int J Colorectal Dis 2010; 25:135-40. [PMID: 19898853 DOI: 10.1007/s00384-009-0818-8] [Citation(s) in RCA: 215] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/09/2009] [Indexed: 02/04/2023]
Abstract
INTRODUCTION It is now clear that inflammation and cancer initiation and progression are linked. Interleukin-6 (IL-6) is a pleiotropic inflammatory cytokine with described cancer stimulatory and also cancer inhibitory properties. The study's aim was to assess the potential of circulating IL-6 as a prognostic indicator in colorectal cancer. MATERIALS AND METHODS A literature search was conducted using PubMed, restricted to articles published in English language. We compared published results in regard to differences in IL-6 levels between healthy controls and colon cancer patients (seven published results), between patients with increasing tumor stages (eight published results), between patients with differences in tumor size (four published results), and between patients with and without liver (three published results) or lung metastasis (one published result). Furthermore, we reviewed the literature in regard to the possible correlation of IL-6 levels with survival time (five published results) and correlation of IL-6 levels and lymph node involvement (three published results). RESULTS Concerning colon tumors, results are consistent. Colon cancer patients reveal higher serum IL-6 levels than healthy controls. Furthermore, higher IL-6 levels are associated with increasing tumor stages and tumor size, with metastasis and decreased survival. CONCLUSION Therefore, circulating IL-6 might be prognostic indicator in colorectal cancer.
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Affiliation(s)
- Heike Knüpfer
- Institute of Clinical Pharmacology, University of Leipzig, Härtelstrasse 16-18, 04107 Leipzig, Germany.
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22
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Active-site determinants of substrate recognition by the metalloproteinases TACE and ADAM10. Biochem J 2009; 424:79-88. [PMID: 19715556 DOI: 10.1042/bj20090549] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The metalloproteinases TACE [tumour necrosis factor alpha-converting enzyme; also known as ADAM17 (a disintegrin and metalloproteinase 17)] and ADAM10 are the primary enzymes responsible for catalysing release of membrane-anchored proteins from the cell surface in metazoan organisms. Although the repertoire of protein substrates for these two proteases is partially overlapping, each one appears to target a subset of unique proteins in vivo. The mechanisms by which the two proteases achieve specificity for particular substrates are not completely understood. We have used peptide libraries to define the cleavage site selectivity of TACE and ADAM10. The two proteases have distinct primary sequence requirements at multiple positions surrounding the cleavage site in their substrates, which allowed us to generate peptide substrates that are highly specific for each of these proteases. The major difference between the two protease specificities maps to the P1' position (immediately downstream of the cleavage site) of the substrate. At this position, TACE is selective for smaller aliphatic residues, whereas ADAM10 can accommodate aromatic amino acids. Using mutagenesis we identified three residues in the S1' pockets of these enzymes that dramatically influence specificity for both peptide and protein substrates. Our results suggest that substrate selectivity of TACE and ADAM10 can be at least partly rationalized by specific features of their active sites.
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Cytokine signalling via gp130 in gastric cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:1623-33. [PMID: 19665497 DOI: 10.1016/j.bbamcr.2009.07.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 07/29/2009] [Accepted: 07/30/2009] [Indexed: 12/17/2022]
Abstract
Cytokine signalling pathways that depend on gp130 are dysregulated in several epithelial cancers including gastric cancer. It has been established that blockade of SHP2 activation of MAPK signalling results in hyperactivation of STAT3 resulting in increased cell proliferation, angiogenesis, inflammation and inhibition of both immunocyte and epithelial cell apoptosis. Additionally, key genes regulated downstream of gp130 via MAPK activation such as the stomach-specific tumor suppressor gene tff1 are suppressed, contributing to the oncogenic outcome. The main cytokine driver of gp130 signalling in the stomach is IL-11, with IL-6 having little activity in the antral stomach in which most pathology initiates. IL-11 is up-regulated in both mouse and human gastric cancer and in pre-neoplastic mucosa. A characteristic gene signature specifically associated with IL-11 drive has been observed, although the prognostic value of the signature has not yet been assessed. Infection of human or mouse stomach with Helicobacter pylori, especially that expressing the CagA cytotoxin, produces constitutive MAPK activation, but also activated STAT3 and increases IL-11 expression. The possibility of designing and utilising small molecule inhibitors of either IL-11 or STAT3 activation may be worthwhile in developing new cancer therapeutics.
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Abstract
The ADAMs (a disintegrin and metalloproteinase) are a fascinating family of transmembrane and secreted proteins with important roles in regulating cell phenotype via their effects on cell adhesion, migration, proteolysis and signalling. Though all ADAMs contain metalloproteinase domains, in humans only 13 of the 21 genes in the family encode functional proteases, indicating that at least for the other eight members, protein–protein interactions are critical aspects of their biological functions. The functional ADAM metalloproteinases are involved in “ectodomain shedding” of diverse growth factors, cytokines, receptors and adhesion molecules. The archetypal activity is shown by ADAM-17 (tumour necrosis factor-α convertase, TACE), which is the principal protease involved in the activation of pro-TNF-α, but whose sheddase functions cover a broad range of cell surface molecules. In particular, ADAM-17 is required for generation of the active forms of Epidermal Growth Factor Receptor (EGFR) ligands, and its function is essential for the development of epithelial tissues. Several other ADAMs have important sheddase functions in particular tissue contexts. Another major family member, ADAM-10, is a principal player in signalling via the Notch and Eph/ephrin pathways. For a growing number of substrates, foremost among them being Notch, cleavage by ADAM sheddases is essential for their subsequent “regulated intramembrane proteolysis” (RIP), which generates cleaved intracellular domains that translocate to the nucleus and regulate gene transcription. Several ADAMs play roles in spermatogenesis and sperm function, potentially by effecting maturation of sperm and their adhesion and migration in the uterus. Other non-catalytic ADAMs function in the CNS via effects on guidance mechanisms. The ADAM family are thus fundamental to many control processes in development and homeostasis, and unsurprisingly they are also linked to pathological states when their functions are dysregulated, including cancer, cardiovascular disease, asthma, Alzheimer’s disease. This review will provide an overview of current knowledge of the human ADAMs, discussing their structure, function, regulation and disease involvement.
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Affiliation(s)
- Dylan R Edwards
- Biomedical Research Centre, School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
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25
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Zhang Z, Humphreys BD, Bonventre JV. Shedding of the urinary biomarker kidney injury molecule-1 (KIM-1) is regulated by MAP kinases and juxtamembrane region. J Am Soc Nephrol 2008; 18:2704-14. [PMID: 17898236 DOI: 10.1681/asn.2007030325] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Kidney injury molecule-1 (KIM-1) is markedly upregulated in renal proximal tubule cells by stimuli that promote dedifferentiation, including ischemic or toxic injury, as well as in cases of tubulointerstitial disease, polycystic kidney disease, and renal cell carcinoma. Structurally, KIM-1 possesses a single transmembrane domain and undergoes membrane-proximal cleavage, which leads to the release of soluble KIM-1 ectodomain into the urine. Urinary KIM-1 ectodomain is a promising sensitive and specific biomarker for acute kidney injury in humans, and therefore it is important to determine what regulates KIM-1 shedding. We found that constitutive cleavage of KIM-1 is mediated by ERK activation, and that cleavage is accelerated by p38 MAP kinase activation. After cleavage, a 14-kD membrane-bound fragment of KIM-1, which contains two highly conserved tyrosine residues, was tyrosine-phosphorylated. Mutagenesis studies demonstrated that the juxtamembrane secondary structure, not the primary amino acid sequence, was critical to the cleavage of KIM-1.
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Affiliation(s)
- Zhiwei Zhang
- Renal Division, Brigham and Women's Hospital, Department of Medicine, Harvard Medical School, and Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Boston, Massachusetts, USA
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Hundhausen C, Schulte A, Schulz B, Andrzejewski MG, Schwarz N, von Hundelshausen P, Winter U, Paliga K, Reiss K, Saftig P, Weber C, Ludwig A. Regulated shedding of transmembrane chemokines by the disintegrin and metalloproteinase 10 facilitates detachment of adherent leukocytes. THE JOURNAL OF IMMUNOLOGY 2007; 178:8064-72. [PMID: 17548644 DOI: 10.4049/jimmunol.178.12.8064] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CX3CL1 (fractalkine) and CXCL16 are unique members of the chemokine family because they occur not only as soluble, but also as membrane-bound molecules. Expressed as type I transmembrane proteins, the ectodomain of both chemokines can be proteolytically cleaved from the cell surface, a process known as shedding. Our previous studies showed that the disintegrin and metalloproteinase 10 (ADAM10) mediates the largest proportion of constitutive CX3CL1 and CXCL16 shedding, but is not involved in the phorbolester-induced release of the soluble chemokines (inducible shedding). In this study, we introduce the calcium-ionophore ionomycin as a novel, very rapid, and efficient inducer of CX3CL1 and CXCL16 shedding. By transfection in COS-7 cells and ADAM10-deficient murine embryonic fibroblasts combined with the use of selective metalloproteinase inhibitors, we demonstrate that the inducible generation of soluble forms of these chemokines is dependent on ADAM10 activity. Analysis of the C-terminal cleavage fragments remaining in the cell membrane reveals multiple cleavage sites used by ADAM10, one of which is preferentially used upon stimulation with ionomycin. In adhesion studies with CX3CL1-expressing ECV-304 cells and cytokine-stimulated endothelial cells, we demonstrate that induced CX3CL1 shedding leads to the release of bound monocytic cell lines and PBMC from their cellular substrate. These data provide evidence for an inducible release mechanism via ADAM10 potentially important for leukocyte diapedesis.
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Rose-John S, Schooltink H. Cytokines are a therapeutic target for the prevention of inflammation-induced cancers. RECENT RESULTS IN CANCER RESEARCH. FORTSCHRITTE DER KREBSFORSCHUNG. PROGRES DANS LES RECHERCHES SUR LE CANCER 2007; 174:57-66. [PMID: 17302185 DOI: 10.1007/978-3-540-37696-5_5] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Interleukin-6 (IL-6) is an inflammatory cytokine with a well-documented role in cancer. The cytokine binds to a membrane-bound IL-6 receptor (IL-6R) and this complex associates with two molecules of the signal transducing protein gp130, initiating intracellular signaling. Whereas gp130 is expressed on all cells of the body, the IL-6R is only found on some cells, mainly hepatocytes and several leukocytes. Cells, which only express gp130 and no IL-6R, cannot respond to IL-6. We have shown that the IL-6R exists as a soluble protein generated by limited proteolysis of the membrane-bound receptor or by translation from an alternatively spliced mRNA. The complex of soluble IL-6R (sIL-6R) and IL-6 can bind to gp130 on cells that lack the membrane-bound IL-6R and trigger gp130 signaling. We have named this process trans-signaling. We review data that show that IL-6 uses classical signaling via the membrane-bound receptor and trans-signaling via the soluble receptor in physiological and pathophysiological situations. We have developed designer cytokines, which specifically enhance or inhibit IL-6 trans-signaling. These designer cytokines have been shown to be extremely useful in therapeutic applications such as blockade of chronic inflammation and cancer.
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Affiliation(s)
- Stefan Rose-John
- Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, Germany
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Lin M, Rose-John S, Grötzinger J, Conrad U, Scheller J. Functional expression of a biologically active fragment of soluble gp130 as an ELP-fusion protein in transgenic plants: purification via inverse transition cycling. Biochem J 2006; 398:577-83. [PMID: 16716147 PMCID: PMC1559449 DOI: 10.1042/bj20060544] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Revised: 05/22/2006] [Accepted: 05/23/2006] [Indexed: 11/17/2022]
Abstract
In murine models of Crohn's disease, rheumatoid arthritis and colon cancer, IL-6 (interleukin-6) signalling via the sIL-6R (soluble IL-6 receptor; termed IL-6 trans-signalling) has been shown to promote the pathology associated with these conditions. These detrimental activities can, however, be selectively blocked by soluble forms of the gp130 (glycoprotein 130) receptor. Although sgp130 (soluble gp130) therefore represents a viable therapeutic modality for the treatment of these conditions, the mass manufacture of such biologics is often expensive. The advent of molecular farming has, however, provided an extremely cost-effective strategy for the engineering of recombinant proteins. Here, we describe the expression and production of a biologically active sgp130 variant that is expressed in transgenic tobacco plants as an ELP (elastin-like peptide)-fusion protein (mini-gp130-ELP). Mini-gp130-ELP consists of the first three domains of gp130 (Ig-like domain and cytokine binding module) fused to 100 repeats of ELP. Expression of mini-gp130-ELP did not affect the growth rate or morphology of the transgenic plants, and purification was achieved using inverse transition cycling. This approach led to an overall yield of 141 microg of purified protein per g of fresh leaf weight. The purified mini-gp130-ELP specifically inhibited sIL-6R-mediated trans-signalling as measured by binding to the IL-6-sIL-6R complex and through its ability to block sIL-6R-mediated activation of STAT3 (signal transducer and activator of transcription 3) phosphorylation and proliferation in human hepatoma cells and murine pre-B-cells. Consequently, the present study validates the potential application of molecular farming in transgenic tobacco plants as a strategy for the expression and purification of therapeutically advantageous biologics such as sgp130.
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Key Words
- cytokine
- elastin-like peptide (elp)
- glycoprotein 130 (gp130)
- inverse transition cycling
- interleukin-6 (il-6)
- tobacco
- camv, cauliflower mosaic virus
- cntf, ciliary neurotrophic factor
- dmem, dulbecco's modified eagle's medium
- ebna, epstein–barr nuclear antigen
- ecl, enhanced chemiluminescence
- elp, elastin-like peptide
- er, endoplasmic reticulum
- fcs, foetal calf serum
- gp130, glycoprotein 130
- hek-293 cell, human embryonic kidney cell
- il, interleukin
- lif, leukaemia inhibitory factor
- mab, monoclonal antibody
- osm, oncostatin m
- sgp130, soluble gp130
- il-6r, il-6 receptor
- sil-6r, soluble il-6r
- stat, signal transducer and activator of transcription
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Affiliation(s)
- Meng Lin
- *Biochemisches Institut, Christian-Albrechts Universität zu Kiel, Olshausenstr. 40, D-24098 Kiel, Germany
| | - Stefan Rose-John
- *Biochemisches Institut, Christian-Albrechts Universität zu Kiel, Olshausenstr. 40, D-24098 Kiel, Germany
| | - Joachim Grötzinger
- *Biochemisches Institut, Christian-Albrechts Universität zu Kiel, Olshausenstr. 40, D-24098 Kiel, Germany
| | - Udo Conrad
- †Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung Gatersleben (IPK), Corrensstrasse 3, D-06466 Gatersleben, Germany
| | - Jürgen Scheller
- *Biochemisches Institut, Christian-Albrechts Universität zu Kiel, Olshausenstr. 40, D-24098 Kiel, Germany
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Tellier E, Canault M, Rebsomen L, Bonardo B, Juhan-Vague I, Nalbone G, Peiretti F. The shedding activity of ADAM17 is sequestered in lipid rafts. Exp Cell Res 2006; 312:3969-80. [PMID: 17010968 DOI: 10.1016/j.yexcr.2006.08.027] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Revised: 08/28/2006] [Accepted: 08/31/2006] [Indexed: 11/24/2022]
Abstract
The tumor necrosis factor-alpha (TNF) converting enzyme (ADAM17) is a metalloprotease-disintegrin responsible for the cleavage of several biologically active transmembrane proteins. However, the substrate specificity of ADAM17 and the regulation of its shedding activity are still poorly understood. Here, we report that during its transport through the Golgi apparatus, ADAM17 is included in cholesterol-rich membrane microdomains (lipid rafts) where its prodomain is cleaved by furin. Consequently, ADAM17 shedding activity is sequestered in lipid rafts, which is confirmed by the fact that metalloproteinase inhibition increases the proportion of ADAM17 substrates (TNF and its receptors TNFR1 and TNFR2) in lipid rafts. Membrane cholesterol depletion increases the ADAM17-dependent shedding of these substrates demonstrating the importance of lipid rafts in the control of this process. Furthermore, ADAM17 substrates are present in different proportions in lipid rafts, suggesting that the entry of each of these substrates in these particular membrane microdomains is specifically regulated. Our data support the idea that one of the mechanisms regulating ADAM17 substrate cleavage involves protein partitioning in lipid rafts.
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Abstract
Interleukin-6 (IL-6) is a cytokine, which plays an important role in many chronic inflammatory diseases. IL-6 belongs to a family of 10 cytokines, which all act via receptor complexes containing the cytokine receptor subunit gp130. On cells, IL-6 first binds to a specific membrane-bound IL-6R and the complex of IL-6 and IL-6R interacts with gp130 leading to signal initiation. Whereas gp130 is widely expressed throughout the body, the IL-6R is only found on some cells including hepatocytes and some leucocytes. A soluble form of the IL-6R is an agonist capable of transmitting signals through interaction with the gp130 protein. In vivo, the IL-6/soluble IL-6R complex stimulates several types of target cells, which are unresponsive to IL-6 alone, as they do not express the membrane-bound IL-6R. We have named this process trans-signalling. We provided evidence that a soluble form of the IL-6 family signalling receptor subunit gp130 is the natural inhibitor of IL-6 trans-signalling responses. We showed that in chronic inflammatory diseases such as inflammatory bowel disease, peritonitis, rheumatoid arthritis, asthma as well as in colon cancer, IL-6 trans-signalling is critically involved in the maintenance of the disease state. Moreover, in all these animal models, the progression of the disease can be interrupted by specifically interfering with IL-6 trans-signalling using recombinant-soluble gp130Fc protein. The pathophysiologic mechanisms by which the IL-6/soluble IL-6R complex perpetuates the inflammatory state are discussed.
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Affiliation(s)
- J Scheller
- Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
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31
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Rose-John S. Designer Cytokines for Human Haematopoietic Progenitor Cell Expansion: Impact for Tissue Regeneration. Stem Cells 2006. [DOI: 10.1007/3-540-31265-x_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Jones SA, Richards PJ, Scheller J, Rose-John S. IL-6 transsignaling: the in vivo consequences. J Interferon Cytokine Res 2005; 25:241-53. [PMID: 15871661 DOI: 10.1089/jir.2005.25.241] [Citation(s) in RCA: 190] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cytokine receptors exist in membrane-bound and soluble forms. They bind their ligands with comparable affinity. Although most soluble receptors are antagonists because they compete with their membrane counterparts for their ligands, some soluble receptors are agonists. In this case, on target cells, the complex of cytokine and soluble cytokine receptor binds to a second receptor subunit and initiates intracellular signal transduction. The soluble receptors of the interleukin-6 (IL-6) family of cytokines--soluble IL-6 receptor (sIL-6R), sIL-11R, and soluble ciliary neurotrophic factor receptor (sCNTFR)--are agonists. In vivo, the IL-6/sIL-6R complex stimulates several types of target cells not stimulated by IL-6 alone, as they do not express the membrane- bound IL-6R. This process has been named transsignaling. We have shown recently that in several chronic inflammatory diseases, such as chronic inflammatory bowl disease, peritonitis, and rheumatoid arthritis, as well as in colon cancer, transsignaling via the sIL-6R complexed to IL-6 is a crucial point in the maintenance of the disease. The mechanism by which the IL-6/sIL-6R complex regulates the inflammatory or neoplastic state is discussed.
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Affiliation(s)
- Simon A Jones
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3US, Wales, UK
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Volchkov VE, Volchkova VA, Dolnik O, Feldmann H, Klenk HD. Polymorphism of Filovirus Glycoproteins. Adv Virus Res 2005; 64:359-81. [PMID: 16139600 DOI: 10.1016/s0065-3527(05)64011-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Viktor E Volchkov
- Biologie des Filovirus, Claude Bernard University Lyon, INSERM U412 69365 Lyon, France
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von Messling V, Milosevic D, Devaux P, Cattaneo R. Canine distemper virus and measles virus fusion glycoprotein trimers: partial membrane-proximal ectodomain cleavage enhances function. J Virol 2004; 78:7894-903. [PMID: 15254162 PMCID: PMC446110 DOI: 10.1128/jvi.78.15.7894-7903.2004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The trimeric fusion (F) glycoproteins of morbilliviruses are activated by furin cleavage of the precursor F(0) into the F(1) and F(2) subunits. Here we show that an additional membrane-proximal cleavage occurs and modulates F protein function. We initially observed that the ectodomain of approximately one in three measles virus (MV) F proteins is cleaved proximal to the membrane. Processing occurs after cleavage activation of the precursor F(0) into the F(1) and F(2) subunits, producing F(1a) and F(1b) fragments that are incorporated in viral particles. We also detected the F(1b) fragment, including the transmembrane domain and cytoplasmic tail, in cells expressing the canine distemper virus (CDV) or mumps virus F protein. Six membrane-proximal amino acids are necessary for efficient CDV F(1a/b) cleavage. These six amino acids can be exchanged with the corresponding MV F protein residues of different sequence without compromising function. Thus, structural elements of different sequence are functionally exchangeable. Finally, we showed that the alteration of a block of membrane-proximal amino acids results in diminished fusion activity in the context of a recombinant CDV. We envisage that selective loss of the membrane anchor in the external subunits of circularly arranged F protein trimers may disengage them from pulling the membrane centrifugally, thereby facilitating fusion pore formation.
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Affiliation(s)
- Veronika von Messling
- Molecular Medicine Program, Mayo Clinic, College of Medicine, Rochester, MN 55905, USA
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35
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Dolnik O, Volchkova V, Garten W, Carbonnelle C, Becker S, Kahnt J, Ströher U, Klenk HD, Volchkov V. Ectodomain shedding of the glycoprotein GP of Ebola virus. EMBO J 2004; 23:2175-84. [PMID: 15103332 PMCID: PMC424403 DOI: 10.1038/sj.emboj.7600219] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2003] [Accepted: 04/02/2004] [Indexed: 01/08/2023] Open
Abstract
In this study, release of abundant amounts of the Ebola virus (EBOV) surface glycoprotein GP in a soluble form from virus-infected cells was investigated. We demonstrate that the mechanism responsible for the release of GP is ectodomain shedding mediated by cellular sheddases. Proteolytic cleavage taking place at amino-acid position D637 removes the transmembrane anchor and liberates complexes consisting of GP1 and truncated GP2 (GP(2delta)) subunits from the cell surface. We show that tumor necrosis factor alpha-converting enzyme (TACE), a member of the ADAM family of zinc-dependent metalloproteases, is involved in EBOV GP shedding. This finding shows for the first time that virus-encoded surface glycoproteins are substrates for ADAMs. Furthermore, we provide evidence that shed GP is present in significant amounts in the blood of virus-infected animals and that it may play an important role in the pathogenesis of infection by efficiently blocking the activity of virus-neutralizing antibodies.
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Affiliation(s)
- Olga Dolnik
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
- Filovirus Laboratory, University Claude Bernard Lyon-1, INSERM U412, IFR128, Lyon, France
| | - Valentina Volchkova
- Filovirus Laboratory, University Claude Bernard Lyon-1, INSERM U412, IFR128, Lyon, France
| | - Wolfgang Garten
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
| | - Caroline Carbonnelle
- Filovirus Laboratory, University Claude Bernard Lyon-1, INSERM U412, IFR128, Lyon, France
| | - Stephan Becker
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
| | - Jörg Kahnt
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany
| | - Ute Ströher
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
| | - Hans-Dieter Klenk
- Institut für Virologie, Philipps-Universität Marburg, Marburg, Germany
| | - Viktor Volchkov
- Filovirus Laboratory, University Claude Bernard Lyon-1, INSERM U412, IFR128, Lyon, France
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Affiliation(s)
- Joaquín Arribas
- Laboratori de Recerca Oncològica, Servei d'Oncologia Mèdica, Hospital Universitari Vall d'Hebron, Barcelona 08035, Spain
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37
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Rose-John S. Coordination of interleukin-6 biology by membrane bound and soluble receptors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 495:145-51. [PMID: 11774558 DOI: 10.1007/978-1-4615-0685-0_19] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- S Rose-John
- Department of Biochemistry, Christian-Albrechts-Universität zu Kiel, Oslhausenstr. 40, D-24098 Kiel, Germany
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38
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Pang S, Chubb AJ, Schwager SL, Ehlers MR, Sturrock ED, Hooper NM. Roles of the juxtamembrane and extracellular domains of angiotensin-converting enzyme in ectodomain shedding. Biochem J 2001; 358:185-92. [PMID: 11485566 PMCID: PMC1222046 DOI: 10.1042/0264-6021:3580185] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Angiotensin-converting enzyme (ACE) is one of a growing number of integral membrane proteins that is shed from the cell surface through proteolytic cleavage by a secretase. To investigate the requirements for ectodomain shedding, we replaced the glycosylphosphatidylinositol addition sequence in membrane dipeptidase (MDP) - a membrane protein that is not shed - with the juxtamembrane stalk, transmembrane (TM) and cytosolic domains of ACE. The resulting construct, MDP-STM(ACE), was targeted to the cell surface in a glycosylated and enzymically active form, and was shed into the medium. The site of cleavage in MDP-STM(ACE) was identified by MS as the Arg(374)-Ser(375) bond, corresponding to the Arg(1203)-Ser(1204) secretase cleavage site in somatic ACE. The release of MDP-STM(ACE) and ACE from the cells was inhibited in an identical manner by batimastat and two other hydroxamic acid-based zinc metallosecretase inhibitors. In contrast, a construct lacking the juxtamembrane stalk, MDP-TM(ACE), although expressed at the cell surface in an enzymically active form, was not shed, implying that the juxtamembrane stalk is the critical determinant of shedding. However, an additional construct, ACEDeltaC, in which the N-terminal domain of somatic ACE was fused to the stalk, TM and cytosolic domains, was also not shed, despite the presence of a cleavable stalk, implying that in contrast with the C-terminal domain, the N-terminal domain lacks a signal required for shedding. These data are discussed in the context of two classes of secretases that differ in their requirements for recognition of substrate proteins.
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Affiliation(s)
- S Pang
- Proteolysis Research Group, School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
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