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Wu Q, Li S, Zhang X, Dong N. Type II Transmembrane Serine Proteases as Modulators in Adipose Tissue Phenotype and Function. Biomedicines 2023; 11:1794. [PMID: 37509434 PMCID: PMC10376093 DOI: 10.3390/biomedicines11071794] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 07/30/2023] Open
Abstract
Adipose tissue is a crucial organ in energy metabolism and thermoregulation. Adipose tissue phenotype is controlled by various signaling mechanisms under pathophysiological conditions. Type II transmembrane serine proteases (TTSPs) are a group of trypsin-like enzymes anchoring on the cell surface. These proteases act in diverse tissues to regulate physiological processes, such as food digestion, salt-water balance, iron metabolism, epithelial integrity, and auditory nerve development. More recently, several members of the TTSP family, namely, hepsin, matriptase-2, and corin, have been shown to play a role in regulating lipid metabolism, adipose tissue phenotype, and thermogenesis, via direct growth factor activation or indirect hormonal mechanisms. In mice, hepsin deficiency increases adipose browning and protects from high-fat diet-induced hyperglycemia, hyperlipidemia, and obesity. Similarly, matriptase-2 deficiency increases fat lipolysis and reduces obesity and hepatic steatosis in high-fat diet-fed mice. In contrast, corin deficiency increases white adipose weights and cell sizes, suppresses adipocyte browning and thermogenic responses, and causes cold intolerance in mice. These findings highlight an important role of TTSPs in modifying cellular phenotype and function in adipose tissue. In this review, we provide a brief description about TTSPs and discuss recent findings regarding the role of hepsin, matriptase-2, and corin in regulating adipose tissue phenotype, energy metabolism, and thermogenic responses.
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Affiliation(s)
- Qingyu Wu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou 215123, China
| | - Shuo Li
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Xianrui Zhang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou 215123, China
| | - Ningzheng Dong
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou 215123, China
- NHC Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, Soochow University, Suzhou 215006, China
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Heri Suselo Y, Indarto D, Wasita B, Hartono H. Alkaloid Fraction of Mirabilis jalapa Linn. Flowers Has Low Cytotoxicity and Increases Iron Absorption through Erythropoietin-Matriptase-2-Hepcidin pathway in Iron Deficiency Hepatocarcinoma Cell Model. Saudi J Biol Sci 2022; 30:103508. [DOI: 10.1016/j.sjbs.2022.103508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 10/25/2022] [Accepted: 11/11/2022] [Indexed: 11/19/2022] Open
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3
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Zhang Y, Sun S, Du C, Hu K, Zhang C, Liu M, Wu Q, Dong N. Transmembrane serine protease TMPRSS2 implicated in SARS-CoV-2 infection is autoactivated intracellularly and requires N-glycosylation for regulation. J Biol Chem 2022; 298:102643. [PMID: 36309092 PMCID: PMC9598255 DOI: 10.1016/j.jbc.2022.102643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/19/2022] [Accepted: 10/20/2022] [Indexed: 01/07/2023] Open
Abstract
Transmembrane protease serine 2 (TMPRSS2) is a membrane-bound protease expressed in many human epithelial tissues, including the airway and lung. TMPRSS2-mediated cleavage of viral spike protein is a key mechanism in severe acute respiratory syndrome coronavirus 2 activation and host cell entry. To date, the cellular mechanisms that regulate TMPRSS2 activity and cell surface expression are not fully characterized. In this study, we examined two major post-translational events, zymogen activation and N-glycosylation, in human TMPRSS2. In experiments with human embryonic kidney 293, bronchial epithelial 16HBE, and lung alveolar epithelial A549 cells, we found that TMPRSS2 was activated via intracellular autocatalysis and that this process was blocked in the presence of hepatocyte growth factor activator inhibitors 1 and 2. By glycosidase digestion and site-directed mutagenesis, we showed that human TMPRSS2 was N-glycosylated. N-glycosylation at an evolutionarily conserved site in the scavenger receptor cysteine-rich domain was required for calnexin-assisted protein folding in the endoplasmic reticulum and subsequent intracellular trafficking, zymogen activation, and cell surface expression. Moreover, we showed that TMPRSS2 cleaved severe acute respiratory syndrome coronavirus 2 spike protein intracellularly in human embryonic kidney 293 cells. These results provide new insights into the cellular mechanism in regulating TMPRSS2 biosynthesis and function. Our findings should help to understand the role of TMPRSS2 in major respiratory viral diseases.
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Affiliation(s)
- Yikai Zhang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China
| | - Shijin Sun
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China
| | - Chunyu Du
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China,NHC Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Kaixuan Hu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China,NHC Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Ce Zhang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China
| | - Meng Liu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China
| | - Qingyu Wu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China,For correspondence: Qingyu Wu; Ningzheng Dong
| | - Ningzheng Dong
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Suzhou Medical College, Soochow University, Suzhou, China,NHC Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China,For correspondence: Qingyu Wu; Ningzheng Dong
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4
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Martin CE, Murray AS, Mackinder JR, Sala-Hamrick KE, Flynn MG, Lundgren JG, Varela FA, List K. TMPRSS13 zymogen activation, surface localization, and shedding is regulated by proteolytic cleavage within the non-catalytic stem region. Biol Chem 2022; 403:969-982. [PMID: 35796294 PMCID: PMC10642292 DOI: 10.1515/hsz-2022-0129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/24/2022] [Indexed: 12/21/2022]
Abstract
TMPRSS13 is a member of the type II transmembrane serine protease (TTSP) family. Here we characterize a novel post-translational mechanism important for TMPRSS13 function: proteolytic cleavage within the extracellular TMPRSS13 stem region located between the transmembrane domain and the first site of N-linked glycosylation at asparagine (N)-250 in the scavenger receptor cysteine rich (SRCR) domain. Importantly, the catalytic competence of TMPRSS13 is essential for stem region cleavage, suggesting an autonomous mechanism of action. Site-directed mutagenesis of the 10 basic amino acids (four arginine and six lysine residues) in this region abrogated zymogen activation and catalytic activity of TMPRSS13, as well as phosphorylation, cell surface expression, and shedding. Mutation analysis of individual arginine residues identified R223, a residue located between the low-density lipoprotein receptor class A domain and the SRCR domain, as important for stem region cleavage. Mutation of R223 causes a reduction in the aforementioned functional processing steps of TMPRSS13. These data provide further insight into the roles of different post-translational modifications as regulators of the function and localization of TMPRSS13. Additionally, the data suggest the presence of complex interconnected regulatory mechanisms that may serve to ensure the proper levels of cell-surface and pericellular TMPRSS13-mediated proteolysis under homeostatic conditions.
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Affiliation(s)
- Carly E. Martin
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Oncology, Wayne State University, Detroit, MI, 48202, USA
| | - Andrew S. Murray
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Oncology, Wayne State University, Detroit, MI, 48202, USA
- Division of Hematological Malignancies and Cellular Therapy, Duke University, Durham, NC, 27708, USA
| | - Jacob R. Mackinder
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT, 05405, USA
| | - Kimberley E. Sala-Hamrick
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Environmental Sciences, University of Michigan School of Public Health, Ann Arbor, MI, 48109, USA
| | - Michael G. Flynn
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
| | - Joseph G. Lundgren
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Oncology, Wayne State University, Detroit, MI, 48202, USA
| | - Fausto A. Varela
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Karin List
- Department of Pharmacology, Wayne State University, Detroit, MI, 48202, USA
- Department of Oncology, Wayne State University, Detroit, MI, 48202, USA
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5
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Pelc LA, Koester SK, Kukla CR, Chen Z, Di Cera E. The active site region plays a critical role in Na + binding to thrombin. J Biol Chem 2022; 298:101458. [PMID: 34861239 PMCID: PMC8695361 DOI: 10.1016/j.jbc.2021.101458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/24/2021] [Accepted: 11/26/2021] [Indexed: 11/23/2022] Open
Abstract
The catalytic activity of thrombin and other enzymes of the blood coagulation and complement cascades is enhanced significantly by binding of Na+ to a site >15 Å away from the catalytic residue S195, buried within the 180 and 220 loops that also contribute to the primary specificity of the enzyme. Rapid kinetics support a binding mechanism of conformational selection where the Na+-binding site is in equilibrium between open (N) and closed (N∗) forms and the cation binds selectively to the N form. Allosteric transduction of this binding step produces enhanced catalytic activity. Molecular details on how Na+ gains access to this site and communicates allosterically with the active site remain poorly defined. In this study, we show that the rate of the N∗→N transition is strongly correlated with the analogous E∗→E transition that governs the interaction of synthetic and physiologic substrates with the active site. This correlation supports the active site as the likely point of entry for Na+ to its binding site. Mutagenesis and structural data rule out an alternative path through the pore defined by the 180 and 220 loops. We suggest that the active site communicates allosterically with the Na+ site through a network of H-bonded water molecules that embeds the primary specificity pocket. Perturbation of the mobility of S195 and its H-bonding capabilities alters interaction with this network and influences the kinetics of Na+ binding and allosteric transduction. These findings have general mechanistic relevance for Na+-activated proteases and allosteric enzymes.
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Affiliation(s)
- Leslie A Pelc
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Sarah K Koester
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Cassandra R Kukla
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Zhiwei Chen
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Enrico Di Cera
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA.
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6
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Function and regulation of corin in physiology and disease. Biochem Soc Trans 2021; 48:1905-1916. [PMID: 33125488 DOI: 10.1042/bst20190760] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/19/2020] [Accepted: 09/22/2020] [Indexed: 02/07/2023]
Abstract
Atrial natriuretic peptide (ANP) is of major importance in the maintenance of electrolyte balance and normal blood pressure. Reduced plasma ANP levels are associated with the increased risk of cardiovascular disease. Corin is a type II transmembrane serine protease that converts the ANP precursor to mature ANP. Corin deficiency prevents ANP generation and alters electrolyte and body fluid homeostasis. Corin is synthesized as a zymogen that is proteolytically activated on the cell surface. Factors that disrupt corin folding, intracellular trafficking, cell surface expression, and zymogen activation are expected to impair corin function. To date, CORIN variants that reduce corin activity have been identified in hypertensive patients. In addition to the heart, corin expression has been detected in non-cardiac tissues, where corin and ANP participate in diverse physiological processes. In this review, we summarize the current knowledge in corin biosynthesis and post-translational modifications. We also discuss tissue-specific corin expression and function in physiology and disease.
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7
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Li S, Wang L, Sun S, Wu Q. Hepsin: a multifunctional transmembrane serine protease in pathobiology. FEBS J 2020; 288:5252-5264. [PMID: 33300264 DOI: 10.1111/febs.15663] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/30/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022]
Abstract
Cell membrane-bound serine proteases are important in the maintenance of physiological homeostasis. Hepsin is a type II transmembrane serine protease highly expressed in the liver. Recent studies indicate that hepsin activates prohepatocyte growth factor in the liver to enhance Met signaling, thereby regulating glucose, lipid, and protein metabolism. In addition, hepsin functions in nonhepatic tissues, including the adipose tissue, kidney, and inner ear, to regulate adipocyte differentiation, urinary protein processing, and auditory function, respectively. In mouse models, hepsin deficiency lowers blood glucose, lipid, and protein levels, impairs uromodulin assembly in renal epithelial cells, and causes hearing loss. Elevated hepsin expression has also been found in many cancers. As a type II transmembrane protease, cell surface expression and zymogen activation are essential for hepsin activity. In this review, we discuss the current knowledge regarding hepsin biosynthesis, activation, and functions in pathobiology.
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Affiliation(s)
- Shuo Li
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, OH, USA
| | - Lina Wang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
| | - Shijin Sun
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
| | - Qingyu Wu
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, OH, USA.,Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
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8
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Zhang C, Zhang Y, Zhang S, Wang Z, Sun S, Liu M, Chen Y, Dong N, Wu Q. Intracellular autoactivation of TMPRSS11A, an airway epithelial transmembrane serine protease. J Biol Chem 2020; 295:12686-12696. [PMID: 32675285 PMCID: PMC7476710 DOI: 10.1074/jbc.ra120.014525] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/14/2020] [Indexed: 12/26/2022] Open
Abstract
Type II transmembrane serine proteases (TTSPs) are a group of enzymes participating in diverse biological processes. Some members of the TTSP family are implicated in viral infection. TMPRSS11A is a TTSP expressed on the surface of airway epithelial cells, which has been shown to cleave and activate spike proteins of the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome coronaviruses (CoVs). In this study, we examined the mechanism underlying the activation cleavage of TMPRSS11A that converts the one-chain zymogen to a two-chain enzyme. By expression in human embryonic kidney 293, esophageal EC9706, and lung epithelial A549 and 16HBE cells, Western blotting, and site-directed mutagenesis, we found that the activation cleavage of human TMPRSS11A was mediated by autocatalysis. Moreover, we found that TMPRSS11A activation cleavage occurred before the protein reached the cell surface, as indicated by studies with trypsin digestion to remove cell surface proteins, treatment with cell organelle-disturbing agents to block intracellular protein trafficking, and analysis of a soluble form of TMPRSS11A without the transmembrane domain. We also showed that TMPRSS11A was able to cleave the SARS-CoV-2 spike protein. These results reveal an intracellular autocleavage mechanism in TMPRSS11A zymogen activation, which differs from the extracellular zymogen activation reported in other TTSPs. These findings provide new insights into the diverse mechanisms in regulating TTSP activation.
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Affiliation(s)
- Ce Zhang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
| | - Yikai Zhang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China.,MOH Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Shengnan Zhang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China.,MOH Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhiting Wang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
| | - Shijin Sun
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China.,MOH Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Meng Liu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
| | - Yue Chen
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China
| | - Ningzheng Dong
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China .,MOH Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Qingyu Wu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Prevention, Soochow University, Suzhou, China .,Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
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9
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Lemke C, Christmann J, Yin J, Alonso JM, Serrano E, Chioua M, Ismaili L, Martínez-Grau MA, Beadle CD, Vetman T, Dato FM, Bartz U, Elsinghorst PW, Pietsch M, Müller CE, Iriepa I, Wille T, Marco-Contelles J, Gütschow M. Chromenones as Multineurotargeting Inhibitors of Human Enzymes. ACS OMEGA 2019; 4:22161-22168. [PMID: 31891098 PMCID: PMC6933783 DOI: 10.1021/acsomega.9b03409] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/21/2019] [Indexed: 06/01/2023]
Abstract
The complex nature of multifactorial diseases, such as Morbus Alzheimer, has produced a strong need to design multitarget-directed ligands to address the involved complementary pathways. We performed a purposive structural modification of a tetratarget small-molecule, that is contilisant, and generated a combinatorial library of 28 substituted chromen-4-ones. The compounds comprise a basic moiety which is linker-connected to the 6-position of the heterocyclic chromenone core. The syntheses were accomplished by Mitsunobu- or Williamson-type ether formations. The resulting library members were evaluated at a panel of seven human enzymes, all of which being involved in the pathophysiology of neurodegeneration. A concomitant inhibition of human acetylcholinesterase and human monoamine oxidase B, with IC50 values of 5.58 and 7.20 μM, respectively, was achieved with the dual-target 6-(4-(piperidin-1-yl)butoxy)-4H-chromen-4-one (7).
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Affiliation(s)
- Carina Lemke
- Pharmaceutical
Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Joscha Christmann
- Bundeswehr
Institute of Pharmacology and Toxicology, Neuherbergstraße 11, 80937 München, Germany
| | - Jiafei Yin
- Pharmaceutical
Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - José M. Alonso
- Laboratory
of Medicinal Chemistry, IQOG, CSIC, C/Juan de la Cierva 3, 28006 Madrid, Spain
| | - Estefanía Serrano
- Laboratory
of Medicinal Chemistry, IQOG, CSIC, C/Juan de la Cierva 3, 28006 Madrid, Spain
| | - Mourad Chioua
- Laboratory
of Medicinal Chemistry, IQOG, CSIC, C/Juan de la Cierva 3, 28006 Madrid, Spain
| | - Lhassane Ismaili
- Neurosciences
intégratives et cliniques EA 481, Pôle de Chimie Organique
et Thérapeutique, Univ. Bourgogne
Franche-Comté, UFR Santé, 19, rue Ambroise Paré, 25000 Besançon, France
| | | | - Christopher D. Beadle
- Lilly Research
Centre, Eli Lilly & Company, Erl Wood Manor,
Windlesham, Surrey GU20 6PH, U.K.
| | - Tatiana Vetman
- Lilly
Research Laboratories, Eli Lilly & Company, Indianapolis 46285, Indiana, United States
| | - Florian M. Dato
- Institute
II of Pharmacology, Center of Pharmacology, Medical Faculty, University of Cologne, Gleueler Strasse 24, 50931 Cologne, Germany
| | - Ulrike Bartz
- Department
of Natural Sciences, University of Applied
Sciences Bonn-Rhein-Sieg, von-Liebig-Strasse 20, 53359 Rheinbach, Germany
| | - Paul W. Elsinghorst
- Pharmaceutical
Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
- Central
Institute of the Bundeswehr Medical Service Munich, Ingolstädter Landstraße
102, 85748 Garching, Germany
| | - Markus Pietsch
- Institute
II of Pharmacology, Center of Pharmacology, Medical Faculty, University of Cologne, Gleueler Strasse 24, 50931 Cologne, Germany
| | - Christa E. Müller
- Pharmaceutical
Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Isabel Iriepa
- Department of Organic and Inorganic Chemistry, University of Alcalá, Ctra. Madrid-Barcelona, Km. 33,6, 28871 Alcalá de Henares, Madrid, Spain
| | - Timo Wille
- Bundeswehr
Institute of Pharmacology and Toxicology, Neuherbergstraße 11, 80937 München, Germany
| | - José Marco-Contelles
- Laboratory
of Medicinal Chemistry, IQOG, CSIC, C/Juan de la Cierva 3, 28006 Madrid, Spain
| | - Michael Gütschow
- Pharmaceutical
Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
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10
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Béliveau F, Tarkar A, Dion SP, Désilets A, Ghinet MG, Boudreault PL, St-Georges C, Marsault É, Paone D, Collins J, Macphee CH, Campobasso N, Groy A, Cottom J, Ouellette M, Pope AJ, Leduc R. Discovery and Development of TMPRSS6 Inhibitors Modulating Hepcidin Levels in Human Hepatocytes. Cell Chem Biol 2019; 26:1559-1572.e9. [DOI: 10.1016/j.chembiol.2019.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 06/06/2019] [Accepted: 09/03/2019] [Indexed: 02/06/2023]
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11
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Autoactivation and calpain-1-mediated shedding of hepsin in human hepatoma cells. Biochem J 2019; 476:2355-2369. [DOI: 10.1042/bcj20190375] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/06/2019] [Accepted: 08/08/2019] [Indexed: 01/19/2023]
Abstract
AbstractHepsin is a transmembrane serine protease implicated in many biological processes, including hepatocyte growth, urinary protein secretion, auditory nerve development, and cancer metastasis. Zymogen activation is critical for hepsin function. To date, how hepsin is activated and regulated in cells remains an enigma. In this study, we conducted site-directed mutagenesis, cell expression, plasma membrane protein labeling, trypsin digestion, Western blotting, and flow cytometry experiments in human hepatoma HepG2 cells, where hepsin was originally discovered, and SMMC-7721 cells. Our results show that hepsin is activated by autocatalysis on the cell surface but not intracellularly. Moreover, we show that hepsin undergoes ectodomain shedding. In the conditioned medium from HepG2 and SMMC-7721 cells, we detected a soluble fragment comprising nearly the entire extracellular region of hepsin. By testing protease inhibitors, gene knockdown, and site-directed mutagenesis, we identified calpain-1 as a primary protease that acted extracellularly to cleave Tyr52 in the juxtamembrane space of hepsin. These results provide new insights into the biochemical and cellular mechanisms that regulate hepsin expression and activity.
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12
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Residues W215, E217 and E192 control the allosteric E*-E equilibrium of thrombin. Sci Rep 2019; 9:12304. [PMID: 31444378 PMCID: PMC6707225 DOI: 10.1038/s41598-019-48839-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/13/2019] [Indexed: 01/07/2023] Open
Abstract
A pre-existing, allosteric equilibrium between closed (E*) and open (E) conformations of the active site influences the level of activity in the trypsin fold and defines ligand binding according to the mechanism of conformational selection. Using the clotting protease thrombin as a model system, we investigate the molecular determinants of the E*-E equilibrium through rapid kinetics and X-ray structural biology. The equilibrium is controlled by three residues positioned around the active site. W215 on the 215-217 segment defining the west wall of the active site controls the rate of transition from E to E* through hydrophobic interaction with F227. E192 on the opposite 190-193 segment defining the east wall of the active site controls the rate of transition from E* to E through electrostatic repulsion of E217. The side chain of E217 acts as a lever that moves the entire 215-217 segment in the E*-E equilibrium. Removal of this side chain converts binding to the active site to a simple lock-and-key mechanism and freezes the conformation in a state intermediate between E* and E. These findings reveal a simple framework to understand the molecular basis of a key allosteric property of the trypsin fold.
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13
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Mao P, Wortham AM, Enns CA, Zhang AS. The catalytic, stem, and transmembrane portions of matriptase-2 are required for suppressing the expression of the iron-regulatory hormone hepcidin. J Biol Chem 2018; 294:2060-2073. [PMID: 30559294 DOI: 10.1074/jbc.ra118.006468] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/13/2018] [Indexed: 12/21/2022] Open
Abstract
Matriptase-2 (MT2) is a type-II transmembrane, trypsin-like serine protease that is predominantly expressed in the liver. It is a key suppressor for the expression of hepatic hepcidin, an iron-regulatory hormone that is induced via the bone morphogenetic protein signaling pathway. A current model predicts that MT2 suppresses hepcidin expression by cleaving multiple components of the induction pathway. MT2 is synthesized as a zymogen that undergoes autocleavage for activation and shedding. However, the biologically active form of MT2 and, importantly, the contributions of different MT2 domains to its function are largely unknown. Here we examined the activities of truncated MT2 that were generated by site-directed mutagenesis or Gibson assembly master mix, and found that the stem region of MT2 determines the specificity and efficacy for substrate cleavage. The transmembrane domain allowed MT2 activation after reaching the plasma membrane, and the cytoplasmic domain facilitated these processes. Further in vivo rescue studies indicated that the entire extracellular and transmembrane domains of MT2 are required to correct the low-hemoglobin, low-serum iron, and high-hepcidin status in MT2 -/- mice. Unlike in cell lines, no autocleavage of MT2 was detected in vivo in the liver, implying that MT2 may also function independently of its proteolytic activity. In conjunction with our previous studies implicating the cytoplasmic domain as an intracellular iron sensor, these observations reveal the importance of each MT2 domain for MT2-mediated substrate cleavage and for its biological function.
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Affiliation(s)
- Peizhong Mao
- From the Department of Cell, Developmental, and Cancer Biology, Oregon Health & Science University, Portland, Oregon 97239
| | - Aaron M Wortham
- From the Department of Cell, Developmental, and Cancer Biology, Oregon Health & Science University, Portland, Oregon 97239
| | - Caroline A Enns
- From the Department of Cell, Developmental, and Cancer Biology, Oregon Health & Science University, Portland, Oregon 97239
| | - An-Sheng Zhang
- From the Department of Cell, Developmental, and Cancer Biology, Oregon Health & Science University, Portland, Oregon 97239
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14
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Abstract
Matriptase-2 (MT2) is a membrane-anchored proteolytic enzyme. It acts as the proteolytic key regulator in human iron homeostasis. A high expression level can lead to iron overload diseases, whereas mutations in the gene encoding MT2, TMPRSS6, may result in various forms of iron deficiency anemia. Recently, MT2 has been reported as a positive prognostic factor in breast and prostate cancers. However, the exact functions of MT2 in various pathophysiological conditions are still not fully understood. In this review, we describe the synthetic tools designed and synthesized to regulate or monitor MT2 proteolytic activity and present the latest knowledge about the role of MT2 in iron homeostasis and cancer.
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15
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Yu R, Han X, Zhang X, Wang Y, Wang T. Circulating soluble corin as a potential biomarker for cardiovascular diseases: A translational review. Clin Chim Acta 2018; 485:106-112. [DOI: 10.1016/j.cca.2018.06.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/22/2018] [Accepted: 06/22/2018] [Indexed: 12/14/2022]
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16
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Mangold M, Gütschow M, Stirnberg M. A Short Peptide Inhibitor as an Activity-Based Probe for Matriptase-2. Pharmaceuticals (Basel) 2018; 11:ph11020049. [PMID: 29883401 PMCID: PMC6027297 DOI: 10.3390/ph11020049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 12/19/2022] Open
Abstract
Matriptase-2 is a type II transmembrane serine protease and a key regulator of systemic iron homeostasis. Since the activation mechanism and several features of the physiological role of matriptase-2 are not fully understood, there is strong need for analytical tools to perform tasks such as distinguishing active and inactive matriptase-2. For this purpose we present a short biotinylated peptide derivative with a chloromethyl ketone group, biotin-RQRR-CMK, as an activity-based probe for matriptase-2. Biotin-RQRR-CMK was kinetically characterized and exhibited a second-order rate constant of inactivation (kinac/Ki) of 10,800 M−1 s−1 towards the matriptase-2 activity in the supernatant of transfected human embryonic kidney (HEK) cells. Biotin-RQRR-CMK was able to label active matriptase-2, as visualized in western blot experiments. Pretreatment with aprotinin, an active-site directed inhibitor of serine proteases, protected matriptase-2 from the reaction with biotin-RQRR-CMK.
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Affiliation(s)
- Martin Mangold
- Pharmaceutical Chemistry I, Pharmaceutical Institute, University of Bonn, Bonn 53113, Germany.
| | - Michael Gütschow
- Pharmaceutical Chemistry I, Pharmaceutical Institute, University of Bonn, Bonn 53113, Germany.
| | - Marit Stirnberg
- Pharmaceutical Chemistry I, Pharmaceutical Institute, University of Bonn, Bonn 53113, Germany.
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17
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Dion SP, Béliveau F, Désilets A, Ghinet MG, Leduc R. Transcriptome analysis reveals TMPRSS6 isoforms with distinct functionalities. J Cell Mol Med 2018; 22:2498-2509. [PMID: 29441715 PMCID: PMC5867103 DOI: 10.1111/jcmm.13562] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 01/10/2018] [Indexed: 11/30/2022] Open
Abstract
TMPRSS6 (matriptase-2) is a type II transmembrane serine protease involved in iron homoeostasis. At the cell surface of hepatocytes, TMPRSS6 cleaves haemojuvelin (HJV) and regulates the BMP/SMAD signalling pathway leading to production of hepcidin, a key regulator of iron absorption. Although four TMPRSS6 human isoforms and three mice Tmprss6 isoforms are annotated in databases (Ensembl and RefSeq), their relative expression or activity has not been studied. Analyses of RNA-seq data and RT-PCR from human tissues reveal that TMPRSS6 isoform 1 (TMPRSS6-1) and 3 are mostly expressed in human testis while TMPRSS6-2 and TMPRSS6-4 are the main transcripts expressed in human liver, testis and pituitary. Furthermore, we confirm the existence and analyse the relative expression of three annotated mice Tmprss6 isoforms. Using heterologous expression in HEK293 and Hep3B cells, we show that all human TMPRSS6 isoforms reach the cell surface but only TMPRSS6-1 undergoes internalization. Moreover, truncated TMPRSS6-3 or catalytically altered TMPRSS6-4 interact with HJV and prevent its cleavage by TMPRSS6-2, suggesting their potential role as dominant negative isoforms. Taken together, our results highlight the importance of understanding the precise function of each TMPRSS6 isoforms both in human and in mouse.
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Affiliation(s)
- Sébastien P. Dion
- Department of Pharmacology‐PhysiologyFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
- Institut de Pharmacologie de SherbrookeFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
| | - François Béliveau
- Department of Pharmacology‐PhysiologyFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
- Institut de Pharmacologie de SherbrookeFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
| | - Antoine Désilets
- Department of Pharmacology‐PhysiologyFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
- Institut de Pharmacologie de SherbrookeFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
| | - Mariana Gabriela Ghinet
- Department of Pharmacology‐PhysiologyFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
- Institut de Pharmacologie de SherbrookeFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
| | - Richard Leduc
- Department of Pharmacology‐PhysiologyFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
- Institut de Pharmacologie de SherbrookeFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQCCanada
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18
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Chakraborty P, Acquasaliente L, Pelc LA, Di Cera E. Interplay between conformational selection and zymogen activation. Sci Rep 2018; 8:4080. [PMID: 29511224 PMCID: PMC5840343 DOI: 10.1038/s41598-018-21728-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 02/09/2018] [Indexed: 11/09/2022] Open
Abstract
Trypsin-like proteases are synthesized as zymogens and activated through a mechanism that folds the active site for efficient binding and catalysis. Ligand binding to the active site is therefore a valuable source of information on the changes that accompany zymogen activation. Using the physiologically relevant transition of the clotting zymogen prothrombin to the mature protease thrombin, we show that the mechanism of ligand recognition follows selection within a pre-existing ensemble of conformations with the active site accessible (E) or inaccessible (E*) to binding. Prothrombin exists mainly in the E* conformational ensemble and conversion to thrombin produces two dominant changes: a progressive shift toward the E conformational ensemble triggered by removal of the auxiliary domains upon cleavage at R271 and a drastic drop of the rate of ligand dissociation from the active site triggered by cleavage at R320. Together, these effects produce a significant (700-fold) increase in binding affinity. Limited proteolysis reveals how the E*-E equilibrium shifts during prothrombin activation and influences exposure of the sites of cleavage at R271 and R320. These new findings on the molecular underpinnings of prothrombin activation are relevant to other zymogens with modular assembly involved in blood coagulation, complement and fibrinolysis.
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Affiliation(s)
- Pradipta Chakraborty
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, 63104, USA
| | - Laura Acquasaliente
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, 63104, USA
| | - Leslie A Pelc
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, 63104, USA
| | - Enrico Di Cera
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, 63104, USA.
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19
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Böttcher-Friebertshäuser E, Garten W, Klenk HD. Membrane-Anchored Serine Proteases: Host Cell Factors in Proteolytic Activation of Viral Glycoproteins. ACTIVATION OF VIRUSES BY HOST PROTEASES 2018. [PMCID: PMC7122464 DOI: 10.1007/978-3-319-75474-1_8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Over one third of all known proteolytic enzymes are serine proteases. Among these, the trypsin-like serine proteases comprise one of the best characterized subfamilies due to their essential roles in blood coagulation, food digestion, fibrinolysis, or immunity. Trypsin-like serine proteases possess primary substrate specificity for basic amino acids. Most of the well-characterized trypsin-like proteases such as trypsin, plasmin, or urokinase are soluble proteases that are secreted into the extracellular environment. At the turn of the millennium, a number of novel trypsin-like serine proteases have been identified that are anchored in the cell membrane, either by a transmembrane domain at the N- or C-terminus or via a glycosylphosphatidylinositol (GPI) linkage. Meanwhile more than 20 membrane-anchored serine proteases (MASPs) have been identified in human and mouse, and some of them have emerged as key regulators of mammalian development and homeostasis. Thus, the MASP corin and TMPRSS6/matriptase-2 have been demonstrated to be the activators of the atrial natriuretic peptide (ANP) and key regulator of hepcidin expression, respectively. Furthermore, MASPs have been recognized as host cell factors activating respiratory viruses including influenza virus as well as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses. In particular, transmembrane protease serine S1 member 2 (TMPRSS2) has been shown to be essential for proteolytic activation and consequently spread and pathogenesis of a number of influenza A viruses in mice and as a factor associated with severe influenza virus infection in humans. This review gives an overview on the physiological functions of the fascinating and rapidly evolving group of MASPs and a summary of the current knowledge on their role in proteolytic activation of viral fusion proteins.
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Affiliation(s)
| | - Wolfgang Garten
- 0000 0004 1936 9756grid.10253.35Institut für Virologie, Philipps Universität, Marburg, Germany
| | - Hans Dieter Klenk
- 0000 0004 1936 9756grid.10253.35Institut für Virologie, Philipps-Universität, Marburg, Germany
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20
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Chen S, Wang H, Li H, Zhang Y, Wu Q. Functional analysis of corin protein domains required for PCSK6-mediated activation. Int J Biochem Cell Biol 2017; 94:31-39. [PMID: 29180304 DOI: 10.1016/j.biocel.2017.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/20/2017] [Accepted: 11/24/2017] [Indexed: 02/08/2023]
Abstract
Atrial natriuretic peptide (ANP) is a cardiac hormone essential for normal blood pressure and cardiac function. Corin is a transmembrane serine protease that activates ANP. Recently, we identified proprotein convertase subtilisin/kexin-6 (PCSK6), also called PACE4, as the long-sought corin activator. Both corin and PCSK6 are expressed in cardiomyocytes, but corin activation occurs only on the cell surface. It remains unknown if cell membrane association is needed for PCSK6 to activate corin. Here we expressed corin deletion mutants in HEK293 cells to analyze the domain structures required for PCSK6-mediated activation. Our results show that soluble corin lacking the transmembrane domain was activated by PCSK6 in the conditioned medium but not intracellularly. Recombinant PCSK6 also activated the soluble corin under cell-free conditions. Moreover, PCSK6-mediated corin activation was not enhanced by cell membrane fractions. These results indicate that cell membrane association is unnecessary for PCSK6 to activate corin. Experiments with monensin that blocks PCSK6 secretion and immunostaining indicated that the soluble corin and PCSK6 were secreted via different intracellular pathways, which may explain the lack of corin activation inside the cell. We also found that the protein domains in the corin pro-peptide region were dispensable for PCSK6-mediated activation and that addition of heparan sulfate and chondroitin sulfate or treatment with heparinase or chondroitinase did not alter corin activation by PCSK6 in HEK293 cells. Together, our results provide important insights into the molecular and cellular mechanisms underlying PCSK6-mediated corin activation that is critical for cardiovascular homeostasis.
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Affiliation(s)
- Shenghan Chen
- From the Human Aging Research Institute and School of Life Science, Nanchang University, Nanchang, China; The Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - Hao Wang
- The Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - Heng Li
- From the Human Aging Research Institute and School of Life Science, Nanchang University, Nanchang, China
| | - Yue Zhang
- The Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Qingyu Wu
- The Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA; The Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China.
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21
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Beckmann AM, Glebov K, Walter J, Merkel O, Mangold M, Schmidt F, Becker-Pauly C, Gütschow M, Stirnberg M. The intact Kunitz domain protects the amyloid precursor protein from being processed by matriptase-2. Biol Chem 2017; 397:777-90. [PMID: 27078672 DOI: 10.1515/hsz-2015-0263] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 04/11/2016] [Indexed: 11/15/2022]
Abstract
Proteolytic processing of the amyloid precursor protein (APP) leads to amyloid-β (Aβ) peptides. So far, the mechanism of APP processing is insufficiently characterized at the molecular level. Whereas the knowledge of Aβ generation by several proteases has been expanded, the contribution of the Kunitz-type protease inhibitor domain (KPI) present in two major APP isoforms to the complex proteolytic processing of APP is poorly understood. In this study, we have identified KPI-containing APP as a very potent, slow-binding inhibitor for the membrane-bound proteolytic regulator of iron homeostasis matriptase-2 by forming stable complexes with its target protease in HEK cells. Inhibition and complex formation depend on the intact KPI domain. By inhibiting matriptase-2, KPI-containing APP is protected from matriptase-2-mediated proteolysis within the Aβ region, thus preventing the generation of N-terminally truncated Aβ.
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22
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Protease Inhibitors in the Interstitial Space. Protein Sci 2016. [DOI: 10.1201/9781315374307-10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Proteolysis in the Interstitium. Protein Sci 2016. [DOI: 10.1201/9781315374307-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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24
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Beckmann AM, Gilberg E, Gattner S, Huang TL, Vanden Eynde JJ, Mayence A, Bajorath J, Stirnberg M, Gütschow M. Evaluation of bisbenzamidines as inhibitors for matriptase-2. Bioorg Med Chem Lett 2016; 26:3741-5. [DOI: 10.1016/j.bmcl.2016.05.071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 05/24/2016] [Accepted: 05/25/2016] [Indexed: 10/21/2022]
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25
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Häußler D, Mangold M, Furtmann N, Braune A, Blaut M, Bajorath J, Stirnberg M, Gütschow M. Phosphono Bisbenzguanidines as Irreversible Dipeptidomimetic Inhibitors and Activity-Based Probes of Matriptase-2. Chemistry 2016; 22:8525-35. [DOI: 10.1002/chem.201600206] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Indexed: 12/15/2022]
Affiliation(s)
- Daniela Häußler
- Pharmaceutical Institute; Pharmaceutical Chemistry I; University of Bonn; An der Immenburg 4 53121 Bonn Germany
| | - Martin Mangold
- Pharmaceutical Institute; Pharmaceutical Chemistry I; University of Bonn; An der Immenburg 4 53121 Bonn Germany
| | - Norbert Furtmann
- Pharmaceutical Institute; Pharmaceutical Chemistry I; University of Bonn; An der Immenburg 4 53121 Bonn Germany
- Department of Life Science Informatics, B-IT; LIMES Program Unit Chemical Biology and Medicinal Chemistry; University of Bonn; Dahlmannstrasse 2 53113 Bonn Germany
| | - Annett Braune
- Department of Gastrointestinal Microbiology; German Institute of Human Nutrition Potsdam-Rehbruecke; Arthur-Scheunert-Allee 114-116 14558 Nuthetal Germany
| | - Michael Blaut
- Department of Gastrointestinal Microbiology; German Institute of Human Nutrition Potsdam-Rehbruecke; Arthur-Scheunert-Allee 114-116 14558 Nuthetal Germany
| | - Jürgen Bajorath
- Department of Life Science Informatics, B-IT; LIMES Program Unit Chemical Biology and Medicinal Chemistry; University of Bonn; Dahlmannstrasse 2 53113 Bonn Germany
| | - Marit Stirnberg
- Pharmaceutical Institute; Pharmaceutical Chemistry I; University of Bonn; An der Immenburg 4 53121 Bonn Germany
| | - Michael Gütschow
- Pharmaceutical Institute; Pharmaceutical Chemistry I; University of Bonn; An der Immenburg 4 53121 Bonn Germany
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26
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Beckmann AM, Maurer E, Lülsdorff V, Wilms A, Furtmann N, Bajorath J, Gütschow M, Stirnberg M. En Route to New Therapeutic Options for Iron Overload Diseases: Matriptase-2 as a Target for Kunitz-Type Inhibitors. Chembiochem 2016; 17:595-604. [PMID: 26762582 DOI: 10.1002/cbic.201500651] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Indexed: 02/04/2023]
Abstract
The cell-surface serine protease matriptase-2 is a critical stimulator of iron absorption by negatively regulating hepcidin, the key hormone of iron homeostasis. Thus, it has attracted much attention as a target in primary and secondary iron overload diseases. Here, we have characterised Kunitz-type inhibitors hepatocyte growth factor activator inhibitor 1 (HAI-1) and HAI-2 as powerful, slow-binding matriptase-2 inhibitors. The binding modes of the matriptase-2-HAI complexes were suggested by molecular modelling. Different assays, including cell-free and cell-based measurements of matriptase-2 activity, determination of inhibition constants and evaluation of matriptase-2 inhibition by analysis of downstream effects in human liver cells, demonstrated that matriptase-2 is an excellent target for Kunitz inhibitors. In particular, HAI-2 is considered a promising scaffold for the design of potent and selective matriptase-2 inhibitors.
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Affiliation(s)
| | - Eva Maurer
- Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany
| | - Verena Lülsdorff
- Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany
| | - Annika Wilms
- Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany
| | - Norbert Furtmann
- Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany.,Department of Life Science Informatics, B-IT, LIMES Program Unit Chemical Biology and Medicinal Chemistry, University of Bonn, Dahlmannstrasse 2, 53113, Bonn, Germany
| | - Jürgen Bajorath
- Department of Life Science Informatics, B-IT, LIMES Program Unit Chemical Biology and Medicinal Chemistry, University of Bonn, Dahlmannstrasse 2, 53113, Bonn, Germany
| | - Michael Gütschow
- Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany
| | - Marit Stirnberg
- Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany.
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27
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3,1-Benzothiazines, 1,4-Benzodioxines and 1,4-Benzoxazines as Inhibitors of Matriptase-2: Outcome of a Focused Screening Approach. Pharmaceuticals (Basel) 2016; 9:ph9010002. [PMID: 26771619 PMCID: PMC4812366 DOI: 10.3390/ph9010002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 01/05/2016] [Accepted: 01/07/2016] [Indexed: 12/30/2022] Open
Abstract
The liver enzyme matriptase-2 is a multi-domain, transmembrane serine protease with an extracellular, C-terminal catalytic domain. Synthetic low-molecular weight inhibitors of matriptase-2 have potential as therapeutics to treat iron overload syndromes, in particular in patients with β-thalassemia. A sub-library of 64 compounds was screened for matriptase-2 inhibition and several active compounds were identified. (S)-Ethyl 2-(benzyl(3-((4-carbamidoylphenoxy)methyl)-2,3-dihydrobenzo[b][1,4]dioxin-6-yl)amino)-2-oxoacetate ((S)-12) showed an IC50 value of less than 10 µM. Structure-activity relationships were discussed and proposals to design new matriptase-2 inhibitors were made.
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28
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Furtmann N, Häußler D, Scheidt T, Stirnberg M, Steinmetzer T, Bajorath J, Gütschow M. Limiting the Number of Potential Binding Modes by Introducing Symmetry into Ligands: Structure-Based Design of Inhibitors for Trypsin-Like Serine Proteases. Chemistry 2015; 22:610-25. [DOI: 10.1002/chem.201503534] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Indexed: 12/18/2022]
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29
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Häußler D, Scheidt T, Stirnberg M, Steinmetzer T, Gütschow M. A Bisbenzamidine Phosphonate as a Janus-faced Inhibitor for Trypsin-like Serine Proteases. ChemMedChem 2015; 10:1641-6. [PMID: 26306030 DOI: 10.1002/cmdc.201500319] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Indexed: 12/19/2022]
Abstract
A hybrid approach was applied for the design of an inhibitor of trypsin-like serine proteases. Compound 16 [(R,R)- and (R,S)-diphenyl (4-(1-(4-amidinobenzylamino)-1-oxo-3-phenylpropan-2-ylcarbamoyl)phenylamino)(4-amidinophenyl)methylphosphonate hydrochloride], prepared in a convergent synthetic procedure, possesses a phosphonate warhead prone to react with the active site serine residue in a covalent, irreversible manner. Each of the two benzamidine moieties of 16 can potentially be accommodated in the S1 pocket of the target enzyme, but only the benzamidine close to the phosphonate group would then promote an irreversible interaction. The Janus-faced inhibitor 16 was evaluated against several serine proteases and caused a pronounced inactivation of human thrombin with a second-order rate constant (kinac /Ki) of 59 500 M(-1) s(-1). With human matriptase, 16 showed preference for a reversible mode of inhibition (IC50 =2.6 μM) as indicated by linear progress curves and enzyme reactivation.
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Affiliation(s)
- Daniela Häußler
- Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn (Germany)
| | - Tamara Scheidt
- Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn (Germany)
| | - Marit Stirnberg
- Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn (Germany)
| | - Torsten Steinmetzer
- Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032 Marburg (Germany)
| | - Michael Gütschow
- Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn (Germany).
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30
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Metalloprotease meprin β is activated by transmembrane serine protease matriptase-2 at the cell surface thereby enhancing APP shedding. Biochem J 2015; 470:91-103. [DOI: 10.1042/bj20141417] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 06/15/2015] [Indexed: 01/16/2023]
Abstract
Metalloprotease meprin β is a sheddase of transmembrane proteins. We identified serine protease matriptase-2 (MT2) as a specific activator of meprin β at the cell surface. This provides mechanistic insight for the regulation of meprin β activity and demonstrates clear differences in proenzyme activation.
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31
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Vogt AD, Chakraborty P, Di Cera E. Kinetic dissection of the pre-existing conformational equilibrium in the trypsin fold. J Biol Chem 2015. [PMID: 26216877 DOI: 10.1074/jbc.m115.675538] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Structural biology has recently documented the conformational plasticity of the trypsin fold for both the protease and zymogen in terms of a pre-existing equilibrium between closed (E*) and open (E) forms of the active site region. How such plasticity is manifested in solution and affects ligand recognition by the protease and zymogen is poorly understood in quantitative terms. Here we dissect the E*-E equilibrium with stopped-flow kinetics in the presence of excess ligand or macromolecule. Using the clotting protease thrombin and its zymogen precursor prethrombin-2 as relevant models we resolve the relative distribution of the E* and E forms and the underlying kinetic rates for their interconversion. In the case of thrombin, the E* and E forms are distributed in a 1:4 ratio and interconvert on a time scale of 45 ms. In the case of prethrombin-2, the equilibrium is shifted strongly (10:1 ratio) in favor of the closed E* form and unfolds over a faster time scale of 4.5 ms. The distribution of E* and E forms observed for thrombin and prethrombin-2 indicates that zymogen activation is linked to a significant shift in the pre-existing equilibrium between closed and open conformations that facilitates ligand binding to the active site. These findings broaden our mechanistic understanding of how conformational transitions control ligand recognition by thrombin and its zymogen precursor prethrombin-2 and have direct relevance to other members of the trypsin fold.
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Affiliation(s)
- Austin D Vogt
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
| | - Pradipta Chakraborty
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
| | - Enrico Di Cera
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
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Gitlin A, Dębowski D, Karna N, Łęgowska A, Stirnberg M, Gütschow M, Rolka K. Inhibitors of Matriptase-2 Based on the Trypsin Inhibitor SFTI-1. Chembiochem 2015; 16:1601-7. [DOI: 10.1002/cbic.201500200] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Indexed: 12/12/2022]
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Zhao N, Nizzi CP, Anderson SA, Wang J, Ueno A, Tsukamoto H, Eisenstein RS, Enns CA, Zhang AS. Low intracellular iron increases the stability of matriptase-2. J Biol Chem 2014; 290:4432-46. [PMID: 25550162 DOI: 10.1074/jbc.m114.611913] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Matriptase-2 (MT2) is a type II transmembrane serine protease that is predominantly expressed in hepatocytes. It suppresses the expression of hepatic hepcidin, an iron regulatory hormone, by cleaving membrane hemojuvelin into an inactive form. Hemojuvelin is a bone morphogenetic protein (BMP) co-receptor. Here, we report that MT2 is up-regulated under iron deprivation. In HepG2 cells stably expressing the coding sequence of the MT2 gene, TMPRSS6, incubation with apo-transferrin or the membrane-impermeable iron chelator, deferoxamine mesylate salt, was able to increase MT2 levels. This increase did not result from the inhibition of MT2 shedding from the cells. Rather, studies using a membrane-permeable iron chelator, salicylaldehyde isonicotinoyl hydrazone, revealed that depletion of cellular iron was able to decrease the degradation of MT2 independently of internalization. We found that lack of the putative endocytosis motif in its cytoplasmic domain largely abolished the sensitivity of MT2 to iron depletion. Neither acute nor chronic iron deficiency was able to alter the association of Tmprss6 mRNA with polyribosomes in the liver of rats indicating a lack of translational regulation by low iron levels. Studies in mice showed that Tmprss6 mRNA was not regulated by iron nor the BMP-mediated signaling with no evident correlation with either Bmp6 mRNA or Id1 mRNA, a target of BMP signaling. These results suggest that regulation of MT2 occurs at the level of protein degradation rather than by changes in the rate of internalization and translational or transcriptional mechanisms and that the cytoplasmic domain of MT2 is necessary for its regulation.
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Affiliation(s)
- Ningning Zhao
- From the Department of Cell and Developmental Biology, Oregon Health and Science University, Portland, Oregon 97239
| | - Christopher P Nizzi
- the Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Sheila A Anderson
- the Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Jiaohong Wang
- the Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, and
| | - Akiko Ueno
- the Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, and
| | - Hidekazu Tsukamoto
- the Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, and the Department of Veteran Affairs, Greater Los Angeles Healthcare System, Los Angeles, California 90073
| | - Richard S Eisenstein
- the Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Caroline A Enns
- From the Department of Cell and Developmental Biology, Oregon Health and Science University, Portland, Oregon 97239
| | - An-Sheng Zhang
- From the Department of Cell and Developmental Biology, Oregon Health and Science University, Portland, Oregon 97239,
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Barré O, Dufour A, Eckhard U, Kappelhoff R, Béliveau F, Leduc R, Overall CM. Cleavage specificity analysis of six type II transmembrane serine proteases (TTSPs) using PICS with proteome-derived peptide libraries. PLoS One 2014; 9:e105984. [PMID: 25211023 PMCID: PMC4161349 DOI: 10.1371/journal.pone.0105984] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/31/2014] [Indexed: 01/08/2023] Open
Abstract
Background Type II transmembrane serine proteases (TTSPs) are a family of cell membrane tethered serine proteases with unclear roles as their cleavage site specificities and substrate degradomes have not been fully elucidated. Indeed just 52 cleavage sites are annotated in MEROPS, the database of proteases, their substrates and inhibitors. Methodology/Principal Finding To profile the active site specificities of the TTSPs, we applied Proteomic Identification of protease Cleavage Sites (PICS). Human proteome-derived database searchable peptide libraries were assayed with six human TTSPs (matriptase, matriptase-2, matriptase-3, HAT, DESC and hepsin) to simultaneously determine sequence preferences on the N-terminal non-prime (P) and C-terminal prime (P’) sides of the scissile bond. Prime-side cleavage products were isolated following biotinylation and identified by tandem mass spectrometry. The corresponding non-prime side sequences were derived from human proteome databases using bioinformatics. Sequencing of 2,405 individual cleaved peptides allowed for the development of the family consensus protease cleavage site specificity revealing a strong specificity for arginine in the P1 position and surprisingly a lysine in P1′ position. TTSP cleavage between R↓K was confirmed using synthetic peptides. By parsing through known substrates and known structures of TTSP catalytic domains, and by modeling the remainder, structural explanations for this strong specificity were derived. Conclusions Degradomics analysis of 2,405 cleavage sites revealed a similar and characteristic TTSP family specificity at the P1 and P1′ positions for arginine and lysine in unfolded peptides. The prime side is important for cleavage specificity, thus making these proteases unusual within the tryptic-enzyme class that generally has overriding non-prime side specificity.
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Affiliation(s)
- Olivier Barré
- Centre for Blood Research, Department of Oral Biological & Medical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Antoine Dufour
- Centre for Blood Research, Department of Oral Biological & Medical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Ulrich Eckhard
- Centre for Blood Research, Department of Oral Biological & Medical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Reinhild Kappelhoff
- Centre for Blood Research, Department of Oral Biological & Medical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - François Béliveau
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Richard Leduc
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Christopher M. Overall
- Centre for Blood Research, Department of Oral Biological & Medical Sciences, University of British Columbia, Vancouver, BC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
- * E-mail:
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Abstract
Iron deficiency anemia is a common global problem whose etiology is typically attributed to acquired inadequate dietary intake and/or chronic blood loss. However, in several kindreds multiple family members are affected with iron deficiency anemia that is unresponsive to oral iron supplementation and only partially responsive to parenteral iron therapy. The discovery that many of these cases harbor mutations in the TMPRSS6 gene led to the recognition that they represent a single clinical entity: iron-refractory iron deficiency anemia (IRIDA). This article reviews clinical features of IRIDA, recent genetic studies, and insights this disorder provides into the regulation of systemic iron homeostasis.
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Jiang J, Yang J, Feng P, Zuo B, Dong N, Wu Q, He Y. N-glycosylation is required for matriptase-2 autoactivation and ectodomain shedding. J Biol Chem 2014; 289:19500-7. [PMID: 24867957 DOI: 10.1074/jbc.m114.555110] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Matriptase-2 is a hepatic membrane serine protease that regulates iron homeostasis. Defects in matriptase-2 cause iron deficiency anemia. In cells, matriptase-2 is synthesized as a zymogen. To date, how matriptase-2 expression and activation are regulated remains poorly understood. Here we expressed human matriptase-2 in HEK293 and hepatic BEL-7402, SMMC-7721, and QGY-7703 cells. By labeling cell surface proteins and Western analysis, we examined matriptase-2 cell surface expression, zymogen activation, and ectodomain shedding. Our results show that matriptase-2 was activated on the cell surface but not intracellularly. Activated matriptase-2 underwent ectodomain shedding, producing soluble fragments in the conditioned medium. By testing inactive mutants, R576A and S762A, we found that matriptase-2 activation and shedding were mediated by its own catalytic activity and that the one-chain form of matriptase-2 had little activity in ectodomain shedding. We made additional matriptase-2 mutants, N136Q, N184Q, N216Q, N338Q, N433Q, N453Q, and N518Q, in which each of the predicted N-glycosylation sites was mutated. All of these mutants were expressed on the cell surface. However, mutants N216Q, N453Q, and N518Q, but not the other mutants, had impaired zymogen activation and ectodomain shedding. Our results indicate that N-glycans at specific sites are critical for matriptase-2 activation. Together, these data provide new insights into the cell surface expression, zymogen activation, and ectodomain shedding of matriptase-2.
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Affiliation(s)
- Jiang Jiang
- From the Cyrus Tang Hematology Center and Ministry of Education Engineering Center of Hematological Disease, the Department of Clinic Laboratories, the Second Affiliated Hospital
| | - Jianfeng Yang
- From the Cyrus Tang Hematology Center and Ministry of Education Engineering Center of Hematological Disease
| | - Ping Feng
- the Department of Clinic Laboratories, the Second Affiliated Hospital
| | - Bin Zuo
- From the Cyrus Tang Hematology Center and Ministry of Education Engineering Center of Hematological Disease
| | - Ningzheng Dong
- From the Cyrus Tang Hematology Center and Ministry of Education Engineering Center of Hematological Disease, the Ministry of Health Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital, and the Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215006, China and
| | - Qingyu Wu
- From the Cyrus Tang Hematology Center and Ministry of Education Engineering Center of Hematological Disease, the Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215006, China and the Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Yang He
- From the Cyrus Tang Hematology Center and Ministry of Education Engineering Center of Hematological Disease, the Ministry of Health Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital, and the Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215006, China and
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37
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Wysocka M, Gruba N, Miecznikowska A, Popow-Stellmaszyk J, Gütschow M, Stirnberg M, Furtmann N, Bajorath J, Lesner A, Rolka K. Substrate specificity of human matriptase-2. Biochimie 2014; 97:121-7. [DOI: 10.1016/j.biochi.2013.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/01/2013] [Indexed: 01/22/2023]
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38
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De Falco L, Sanchez M, Silvestri L, Kannengiesser C, Muckenthaler MU, Iolascon A, Gouya L, Camaschella C, Beaumont C. Iron refractory iron deficiency anemia. Haematologica 2013; 98:845-53. [PMID: 23729726 DOI: 10.3324/haematol.2012.075515] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Iron refractory iron deficiency anemia is a hereditary recessive anemia due to a defect in the TMPRSS6 gene encoding Matriptase-2. This protein is a transmembrane serine protease that plays an essential role in down-regulating hepcidin, the key regulator of iron homeostasis. Hallmarks of this disease are microcytic hypochromic anemia, low transferrin saturation and normal/high serum hepcidin values. The anemia appears in the post-natal period, although in some cases it is only diagnosed in adulthood. The disease is refractory to oral iron treatment but shows a slow response to intravenous iron injections and partial correction of the anemia. To date, 40 different Matriptase-2 mutations have been reported, affecting all the functional domains of the large ectodomain of the protein. In vitro experiments on transfected cells suggest that Matriptase-2 cleaves Hemojuvelin, a major regulator of hepcidin expression and that this function is altered in this genetic form of anemia. In contrast to the low/undetectable hepcidin levels observed in acquired iron deficiency, in patients with Matriptase-2 deficiency, serum hepcidin is inappropriately high for the low iron status and accounts for the absent/delayed response to oral iron treatment. A challenge for the clinicians and pediatricians is the recognition of the disorder among iron deficiency and other microcytic anemias commonly found in pediatric patients. The current treatment of iron refractory iron deficiency anemia is based on parenteral iron administration; in the future, manipulation of the hepcidin pathway with the aim of suppressing it might become an alternative therapeutic approach.
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Barranco-Medina S, Pozzi N, Vogt AD, Di Cera E. Histone H4 promotes prothrombin autoactivation. J Biol Chem 2013; 288:35749-57. [PMID: 24178300 DOI: 10.1074/jbc.m113.509786] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Recent studies have documented the ability of prothrombin to spontaneously convert to the mature protease thrombin when Arg-320 becomes exposed to solvent for proteolytic attack upon mutation of residues in the activation domain. Whether prothrombin autoactivation occurs in the wild-type under conditions relevant to physiology remains unknown. Here, we report that binding of histone H4 to prothrombin under physiological conditions generates thrombin by autoactivation. The effect is abrogated by mutation of the catalytic Ser-525 and requires the presence of the Gla domain. Fluorescence titrations document direct binding of histone H4 to prothrombin with an affinity in the low nm range. Stopped flow data and luminescence resonance energy transfer measurements indicate that the binding mechanism obeys conformational selection. Among the two conformations of prothrombin, collapsed and fully extended, histone H4 binds selectively to the collapsed form and induces a transition toward a new conformation where the distance between Ser-101 in kringle-1 and Ser-210 in kringle-2 increases by 13 Å. These findings confirm the molecular plasticity of prothrombin emerged from recent structural studies and suggest that different conformations of the inter-kringle linker domain determine the functional behavior of prothrombin. The results also broaden our mechanistic understanding of the prothrombotic phenotype observed during cellular damage due to the release of histones in the blood stream. Prothrombin autoactivation induced by histone H4 emerges as a mechanism of pathophysiological relevance through which thrombin is generated independently of activation of the coagulation cascade.
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Affiliation(s)
- Sergio Barranco-Medina
- From the Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
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40
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Hepatocyte growth factor activator inhibitor type 2 (HAI-2) modulates hepcidin expression by inhibiting the cell surface protease matriptase-2. Biochem J 2013; 450:583-93. [PMID: 23293962 DOI: 10.1042/bj20121518] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Matriptase-2, a recently identified cell surface protease, is the key enzyme of iron homoeostasis modulating the expression of the liver peptide hormone hepcidin. HAI (hepatocyte growth factor activator inhibitor) types 1 and 2 (HAI-1 and HAI-2 respectively) have been shown to inhibit the close homologue, i.e. matriptase. By co-expressing matriptase-2 and the inhibitor HAI-2 we have identified HAI-2 displaying high inhibitory potential against matriptase-2 at the cell surface as well as in conditioned medium. Accordingly, complex formation between matriptase-2 and HAI-2 was demonstrated by isolation of the complex via immobilizing either HAI-2 or matriptase-2 from lysates and conditioned medium of co-expressing cells. Furthermore, HAI-2 indirectly influences the expression of the hepcidin-encoding gene HAMP. The inhibitor abrogates the matriptase-2-mediated suppression of HAMP expression, presumably by inhibiting the supposed potential of matriptase-2 to cleave membrane-bound HJV (haemojuvelin). Taken together, the results of the present study have characterized HAI-2 as an inhibitor of matriptase-2 that modulates the synthesis of hepcidin and provides new insights into the regulatory mechanism of iron homoeostasis, with clinical importance for a treatment of iron overload diseases.
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41
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Pozzi N, Chen Z, Zapata F, Niu W, Barranco-Medina S, Pelc LA, Di Cera E. Autoactivation of thrombin precursors. J Biol Chem 2013; 288:11601-10. [PMID: 23467412 DOI: 10.1074/jbc.m113.451542] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Trypsin-like proteases are synthesized as inactive zymogens and convert to the mature form upon activation by specific enzymes, often assisted by cofactors. Central to this paradigm is that the zymogen does not convert spontaneously to the mature enzyme, which in turn does not feed back to activate its zymogen form. In the blood, the zymogens prothrombin and prethrombin-2 require the prothrombinase complex to be converted to the mature protease thrombin, which is unable to activate prothrombin or prethrombin-2. Here, we show that replacement of key residues within the activation domain causes these zymogens to spontaneously convert to thrombin. The conversion is started by the zymogen itself, which is capable of binding ligands at the active site, and is abrogated by inactivation of the catalytic residue Ser-195. The product of autoactivation is functionally and structurally equivalent to wild-type thrombin. Zymogen autoactivation is explained by conformational selection, a basic property of the trypsin fold uncovered by structural and rapid kinetics studies. Both the zymogen and protease undergo a pre-existing equilibrium between active and inactive forms. The equilibrium regulates catalytic activity in the protease and has the potential to unleash activity in the zymogen to produce autoactivation. A new strategy emerges for the facile production of enzymes through zymogen autoactivation that is broadly applicable to trypsin-like proteases of biotechnological and clinical interest.
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Affiliation(s)
- Nicola Pozzi
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, USA
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42
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Active site mapping of trypsin, thrombin and matriptase-2 by sulfamoyl benzamidines. Bioorg Med Chem 2012; 20:6489-505. [DOI: 10.1016/j.bmc.2012.08.042] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 08/16/2012] [Indexed: 12/16/2022]
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43
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Guillem F, Kannengiesser C, Oudin C, Lenoir A, Matak P, Donadieu J, Isidor B, Méchinaud F, Aguilar-Martinez P, Beaumont C, Vaulont S, Grandchamp B, Nicolas G. Inactive matriptase-2 mutants found in IRIDA patients still repress hepcidin in a transfection assay despite having lost their serine protease activity. Hum Mutat 2012; 33:1388-96. [PMID: 22581667 DOI: 10.1002/humu.22116] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 05/02/2012] [Indexed: 12/21/2022]
Abstract
Mutations of the TMPRSS6 gene, which encodes Matriptase-2, are responsible for iron-refractory iron-deficiency anemia. Matriptase-2 is a transmembrane protease that downregulates hepcidin expression. We report one frameshift (p.Ala605ProfsX8) and four novel missense mutations (p.Glu114Lys, p.Leu235Pro, p.Tyr418Cys, p.Pro765Ala) found in IRIDA patients. These mutations lead to changes in both the catalytic and noncatalytic domains of Matriptase-2. Analyses of the mutant proteins revealed a reduction of autoactivating cleavage and the loss of N-Boc-Gln-Ala-Arg-p-nitroanilide hydrolysis. This resulted either from a direct modification of the active site or from the lack of the autocatalytic cleavage that transforms the zymogen into an active protease. In a previously described transfection assay measuring the ability of Matriptase-2 to repress the hepcidin gene (HAMP) promoter, all mutants retained some, if not all, of their transcriptional repression activity. This suggests that caution is called for in interpreting the repression assay in assessing the functional relevance of Matriptase-2 substitutions. We propose that Matriptase-2 activity should be measured directly in the cell medium of transfected cells using the chromogenic substrate. This simple test can be used to determine whether a sequence variation leading to an amino acid substitution is functionally relevant or not.
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44
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Corin in clinical laboratory diagnostics. Clin Chim Acta 2011; 413:378-83. [PMID: 22093942 DOI: 10.1016/j.cca.2011.10.032] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 10/21/2011] [Accepted: 10/25/2011] [Indexed: 12/11/2022]
Abstract
Corin is a transmembrane serine protease identified in the heart, where it converts natriuretic peptides from inactive precursors to mature active forms. Studies in animal models and patients with hypertension and heart disease demonstrate that corin is critical in maintaining normal blood pressure and cardiac function. Like many proteolytic enzymes, corin expression and activity are regulated. Cell biology experiments indicate that transcriptional control, intracellular protein trafficking, cell surface targeting, zymogen activation and ectodomain shedding are important mechanisms in regulating corin expression and activity in the heart. More recently, soluble corin was detected in human blood and its levels were found to be reduced in patients with heart failure (HF). These findings indicate that corin deficiency may be involved in the pathogenesis of HF and suggest that soluble corin may be used as a biomarker for the disease. In this review, we describe the function and regulation of corin and discuss recent studies of soluble corin in human blood and its potential use as a biomarker for HF.
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45
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Maurer E, Sisay MT, Stirnberg M, Steinmetzer T, Bajorath J, Gütschow M. Insights into matriptase-2 substrate binding and inhibition mechanisms by analyzing active-site-mutated variants. ChemMedChem 2011; 7:68-72. [PMID: 21919209 DOI: 10.1002/cmdc.201100350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Indexed: 02/04/2023]
Affiliation(s)
- Eva Maurer
- Pharmazeutisches Institut, Universität Bonn, Bonn, Germany
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46
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Antalis TM, Bugge TH, Wu Q. Membrane-anchored serine proteases in health and disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 99:1-50. [PMID: 21238933 PMCID: PMC3697097 DOI: 10.1016/b978-0-12-385504-6.00001-4] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Serine proteases of the trypsin-like family have long been recognized to be critical effectors of biological processes as diverse as digestion, blood coagulation, fibrinolysis, and immunity. In recent years, a subgroup of these enzymes has been identified that are anchored directly to plasma membranes, either by a carboxy-terminal transmembrane domain (Type I), an amino-terminal transmembrane domain with a cytoplasmic extension (Type II or TTSP), or through a glycosylphosphatidylinositol (GPI) linkage. Recent biochemical, cellular, and in vivo analyses have now established that membrane-anchored serine proteases are key pericellular contributors to processes vital for development and the maintenance of homeostasis. This chapter reviews our current knowledge of the biological and physiological functions of these proteases, their molecular substrates, and their contributions to disease.
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Affiliation(s)
- Toni M Antalis
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, Maryland, USA
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47
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Béliveau F, Brulé C, Désilets A, Zimmerman B, Laporte SA, Lavoie CL, Leduc R. Essential role of endocytosis of the type II transmembrane serine protease TMPRSS6 in regulating its functionality. J Biol Chem 2011; 286:29035-29043. [PMID: 21724843 DOI: 10.1074/jbc.m111.223461] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The type II transmembrane serine protease TMPRSS6 (also known as matriptase-2) controls iron homeostasis through its negative regulation of expression of hepcidin, a key hormone involved in iron metabolism. Upstream of the hepcidin-regulated signaling pathway, TMPRSS6 cleaves its target substrate hemojuvelin (HJV) at the plasma membrane, but the dynamics of the cell-surface expression of the protease have not been addressed. Here, we report that TMPRSS6 undergoes constitutive internalization in transfected HEK293 cells and in two human hepatic cell lines, HepG2 and primary hepatocytes, both of which express TMPRSS6 endogenously. Cell surface-labeled TMPRSS6 was internalized and was detected in clathrin- and AP-2-positive vesicles via a dynamin-dependent pathway. The endocytosed TMPRSS6 next transited in early endosomes and then to lysosomes. Internalization of TMPRSS6 is dependent on specific residues within its N-terminal cytoplasmic domain, as site-directed mutagenesis of these residues abrogated internalization and maintained the enzyme at the cell surface. Cells coexpressing these mutants and HJV produced significantly decreased levels of hepcidin compared with wild-type TMPRSS6 due to the sustained cleavage of HJV at the cell surface by TMPRSS6 mutants. Our results underscore for the first time the importance of TMPRSS6 trafficking at the plasma membrane in the regulation of hepcidin expression, an event that is essential for iron homeostasis.
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Affiliation(s)
- François Béliveau
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Cédric Brulé
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Antoine Désilets
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Brandon Zimmerman
- Departments of Medicine and Pharmacology & Therapeutics, McGill University Health Center Research Institute, McGill University, Montreal H3A 1A1, Canada
| | - Stéphane A Laporte
- Departments of Medicine and Pharmacology & Therapeutics, McGill University Health Center Research Institute, McGill University, Montreal H3A 1A1, Canada
| | - Christine L Lavoie
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Richard Leduc
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.
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Abstract
Mutations in transmembrane protease, serine 6 (TMPRSS6), encoding matriptase-2, are responsible for the familial anemia disorder iron-refractory iron deficiency anemia (IRIDA). Patients with IRIDA have inappropriately elevated levels of the iron regulatory hormone hepcidin, suggesting that TMPRSS6 is involved in negatively regulating hepcidin expression. Hepcidin is positively regulated by iron via the bone morphogenetic protein (BMP)-SMAD signaling pathway. In this study, we investigated whether BMP6 and iron also regulate TMPRSS6 expression. Here we demonstrate that, in vitro, treatment with BMP6 stimulates TMPRSS6 expression at the mRNA and protein levels and leads to an increase in matriptase-2 activity. Moreover, we identify that inhibitor of DNA binding 1 is the key element of the BMP-SMAD pathway to regulate TMPRSS6 expression in response to BMP6 treatment. Finally, we show that, in mice, Tmprss6 mRNA expression is stimulated by chronic iron treatment or BMP6 injection and is blocked by injection of neutralizing antibody against BMP6. Our results indicate that BMP6 and iron not only induce hepcidin expression but also induce TMPRSS6, a negative regulator of hepcidin expression. Modulation of TMPRSS6 expression could serve as a negative feedback inhibitor to avoid excessive hepcidin increases by iron to help maintain tight homeostatic balance of systemic iron levels.
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Jiang J, Wu S, Wang W, Chen S, Peng J, Zhang X, Wu Q. Ectodomain shedding and autocleavage of the cardiac membrane protease corin. J Biol Chem 2011; 286:10066-72. [PMID: 21288900 PMCID: PMC3060458 DOI: 10.1074/jbc.m110.185082] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 01/21/2011] [Indexed: 11/06/2022] Open
Abstract
Corin is a cardiac membrane protease that activates natriuretic peptides. It is unknown how corin function is regulated. Recently, soluble corin was detected in human plasma, suggesting that corin may be shed from cardiomyocytes. Here we examined soluble corin production and activity and determined the proteolytic enzymes responsible for corin cleavage. We expressed human corin in HEK 293 cells and detected three soluble fragments of ∼180, ∼160, and ∼100 kDa, respectively, in the cultured medium by Western blot analysis. All three fragments were derived from activated corin molecules. Similar results were obtained in HL-1 cardiomyocytes. Using protease inhibitors, ionomycin and phorbol myristate acetate stimulation, small interfering RNA knockdown, and site-directed mutagenesis, we found that ADAM10 was primarily responsible for shedding corin in its juxtamembrane region to release the ∼180-kDa fragment, corresponding to the near-entire extracellular region. In contrast, the ∼160- and ∼100-kDa fragments were from corin autocleavage at Arg-164 in frizzled 1 domain and Arg-427 in LDL receptor 5 domain, respectively. In functional studies, the ∼180-kDa fragment activated atrial natriuretic peptide, whereas the ∼160- and ∼100-kDa fragments did not. Our data indicate that ADAM-mediated shedding and corin autocleavage are important mechanisms regulating corin function and preventing excessive, potentially hazardous, proteolytic activities in the heart.
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Affiliation(s)
- Jingjing Jiang
- From the Department of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195 and
- the Department of Pharmacology, Shandong University Medical School, Jinan 250012, China, and
| | - Shannon Wu
- From the Department of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195 and
| | - Wei Wang
- From the Department of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195 and
| | - Shenghan Chen
- From the Department of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195 and
| | - Jianhao Peng
- From the Department of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195 and
| | - Xiumei Zhang
- the Department of Pharmacology, Shandong University Medical School, Jinan 250012, China, and
| | - Qingyu Wu
- From the Department of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195 and
- the Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital, Soochow University, Suzhou 215123, China
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50
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Rousselet E, Benjannet S, Marcinkiewicz E, Asselin MC, Lazure C, Seidah NG. Proprotein convertase PC7 enhances the activation of the EGF receptor pathway through processing of the EGF precursor. J Biol Chem 2011; 286:9185-95. [PMID: 21209099 DOI: 10.1074/jbc.m110.189936] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Although the processing profile of the membrane-bound epidermal growth factor precursor (pro-EGF) is tissue-specific, it has not been investigated at the cellular level nor have the cognate proteinases been defined. Among the proprotein convertases (PCs), only the membrane-bound PC7, the most ancient and conserved basic amino acid-specific PC family member, induces the processing of pro-EGF into an ∼115-kDa transmembrane form (EGF-115) at an unusual VHPR(290)↓A motif. Because site-directed mutagenesis revealed that Arg(290) is not critical, the generation of EGF-115 by PC7 is likely indirect. This was confirmed by testing a wide range of protease inhibitors, which revealed that the production of EGF-115 is most probably achieved via the activation by PC7 of a latent serine and/or cysteine protease(s). EGF-115 is more abundant at the cell surface than pro-EGF and is associated with a stronger EGF receptor (EGFR) activation, as evidenced by higher levels of phosphorylated ERK1/2. This suggests that the generation of EGF-115 represents a regulatory mechanism of juxtacrine EGFR activation. Thus, PC7 is distinct from the other PCs in its ability to enhance the activation of the cell surface EGFR.
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Affiliation(s)
- Estelle Rousselet
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, Montreal, Quebec H2W 1R7, Canada
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