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Mays CE, Trinh THT, Telling G, Kang HE, Ryou C. Endoproteolysis of cellular prion protein by plasmin hinders propagation of prions. Front Mol Neurosci 2022; 15:990136. [PMID: 36117913 PMCID: PMC9478470 DOI: 10.3389/fnmol.2022.990136] [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: 07/09/2022] [Accepted: 08/15/2022] [Indexed: 01/21/2023] Open
Abstract
Many questions surround the underlying mechanism for the differential metabolic processing observed for the prion protein (PrP) in healthy and prion-infected mammals. Foremost, the physiological α-cleavage of PrP interrupts a region critical for both toxicity and conversion of cellular PrP (PrP C ) into its misfolded pathogenic isoform (PrP Sc ) by generating a glycosylphosphatidylinositol (GPI)-anchored C1 fragment. During prion diseases, alternative β-cleavage of PrP becomes prominent, producing a GPI-anchored C2 fragment with this particular region intact. It remains unexplored whether physical up-regulation of α-cleavage can inhibit disease progression. Furthermore, several pieces of evidence indicate that a disintegrin and metalloproteinase (ADAM) 10 and ADAM17 play a much smaller role in the α-cleavage of PrP C than originally believed, thus presenting the need to identify the primary protease(s) responsible. For this purpose, we characterized the ability of plasmin to perform PrP α-cleavage. Then, we conducted functional assays using protein misfolding cyclic amplification (PMCA) and prion-infected cell lines to clarify the role of plasmin-mediated α-cleavage during prion propagation. Here, we demonstrated an inhibitory role of plasmin for PrP Sc formation through PrP α-cleavage that increased C1 fragments resulting in reduced prion conversion compared with non-treated PMCA and cell cultures. The reduction of prion infectious titer in the bioassay of plasmin-treated PMCA material also supported the inhibitory role of plasmin on PrP Sc replication. Our results suggest that plasmin-mediated endoproteolytic cleavage of PrP may be an important event to prevent prion propagation.
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Affiliation(s)
- Charles E. Mays
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Trang H. T. Trinh
- Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, South Korea,Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, South Korea
| | - Glenn Telling
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY, United States,Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States,Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Hae-Eun Kang
- Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States,Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States,Reference Laboratory for Chronic Wasting Disease (CWD), Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon, South Korea,Hae-Eun Kang,
| | - Chongsuk Ryou
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY, United States,Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, South Korea,Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, South Korea,Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States,*Correspondence: Chongsuk Ryou,
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2
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Zattoni M, Mearelli M, Vanni S, Colini Baldeschi A, Tran TH, Ferracin C, Catania M, Moda F, Di Fede G, Giaccone G, Tagliavini F, Zanusso G, Ironside JW, Ferrer I, Legname G. Serpin Signatures in Prion and Alzheimer's Diseases. Mol Neurobiol 2022; 59:3778-3799. [PMID: 35416570 PMCID: PMC9148297 DOI: 10.1007/s12035-022-02817-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/26/2022] [Indexed: 12/17/2022]
Abstract
Serpins represent the most broadly distributed superfamily of proteases inhibitors. They contribute to a variety of physiological functions and any alteration of the serpin-protease equilibrium can lead to severe consequences. SERPINA3 dysregulation has been associated with Alzheimer's disease (AD) and prion diseases. In this study, we investigated the differential expression of serpin superfamily members in neurodegenerative diseases. SERPIN expression was analyzed in human frontal cortex samples from cases of sporadic Creutzfeldt-Jakob disease (sCJD), patients at early stages of AD-related pathology, and age-matched controls not affected by neurodegenerative disorders. In addition, we studied whether Serpin expression was dysregulated in two animal models of prion disease and AD.Our analysis revealed that, besides the already observed upregulation of SERPINA3 in patients with prion disease and AD, SERPINB1, SERPINB6, SERPING1, SERPINH1, and SERPINI1 were dysregulated in sCJD individuals compared to controls, while only SERPINB1 was upregulated in AD patients. Furthermore, we analyzed whether other serpin members were differentially expressed in prion-infected mice compared to controls and, together with SerpinA3n, SerpinF2 increased levels were observed. Interestingly, SerpinA3n transcript and protein were upregulated in a mouse model of AD. The SERPINA3/SerpinA3nincreased anti-protease activity found in post-mortem brain tissue of AD and prion disease samples suggest its involvement in the neurodegenerative processes. A SERPINA3/SerpinA3n role in neurodegenerative disease-related protein aggregation was further corroborated by in vitro SerpinA3n-dependent prion accumulation changes. Our results indicate SERPINA3/SerpinA3n is a potential therapeutic target for the treatment of prion and prion-like neurodegenerative diseases.
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Affiliation(s)
- Marco Zattoni
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy
| | - Marika Mearelli
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy.,German Center for Neurodegenerative Diseases (DZNE), 72076, Tübingen, Germany
| | - Silvia Vanni
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy.,Osteoncology Unit, Bioscience Laboratory, IRCCS Istituto Romagnolo Per Lo Studio Dei Tumori (IRST) "Dino Amadori", 47014, Meldola, Italy
| | - Arianna Colini Baldeschi
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy.,Institute of Biomedicine, Department of Pathology and Experimental Therapeutics, Bellvitge University Hospital-IDIBELL, Barcelona, Spain
| | - Thanh Hoa Tran
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy.,VN-UK Institute for Research and Executive Education, The University of Danang, Da Nang, Vietnam
| | - Chiara Ferracin
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy
| | - Marcella Catania
- Division of Neurology 5 and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fabio Moda
- Division of Neurology 5 and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Giuseppe Di Fede
- Division of Neurology 5 and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Giorgio Giaccone
- Division of Neurology 5 and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fabrizio Tagliavini
- Scientific Directorate, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Gianluigi Zanusso
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - James W Ironside
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Isidre Ferrer
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Hospitalet de Llobregat, Spain.,Institute of Biomedical Research of Bellvitge (IDIBELL), Hospitalet de Llobregat, Spain.,Biomedical Research Network Center of Neurodegenerative Diseases (CIBERNED), Hospitalet de Llobregat, Spain
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy.
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3
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Mattei V, Manganelli V, Martellucci S, Capozzi A, Mantuano E, Longo A, Ferri A, Garofalo T, Sorice M, Misasi R. A multimolecular signaling complex including PrP C and LRP1 is strictly dependent on lipid rafts and is essential for the function of tissue plasminogen activator. J Neurochem 2019; 152:468-481. [PMID: 31602645 DOI: 10.1111/jnc.14891] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/04/2019] [Accepted: 10/07/2019] [Indexed: 12/17/2022]
Abstract
Prion protein (PrPC ) localizes stably in lipid rafts microdomains and is able to recruit downstream signal transduction pathways by the interaction with promiscuous partners. Other proteins have the ability to occasionally be recruited to these specialized membrane areas, within multimolecular complexes. Among these, we highlight the presence of the low-density lipoprotein receptor-related protein 1 (LRP1), which was found localized transiently in lipid rafts, suggesting a different function of this receptor that through lipid raft becomes able to activate a signal transduction pathway triggered by specific ligands, including Tissue plasminogen activator (tPA). Since it has been reported that PrPC participates in the tPA-mediated plasminogen activation, in this study, we describe the role of lipid rafts in the recruitment and activation of downstream signal transduction pathways mediated by the interaction among tPA, PrPC and LRP1 in human neuroblastoma SK-N-BE2 cell line. Co-immunoprecipitation analysis reveals a consistent association between PrPC and GM1, as well as between LRP1 and GM1, indicating the existence of a glycosphingolipid-enriched multimolecular complex. In our cell model, knocking-down PrPC by siRNA impairs ERK phosphorylation induced by tPA. Moreover the alteration of the lipidic milieu of lipid rafts, perturbing the physical/functional interaction between PrPC and LRP1, inhibits this response. We show that LRP1 and PrPC , following tPA stimulation, may function as a system associated with lipid rafts, involved in receptor-mediated neuritogenic pathway. We suggest this as a multimolecular signaling complex, whose activity depends strictly on the integrity of lipid raft and is involved in the neuritogenic signaling.
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Affiliation(s)
- Vincenzo Mattei
- Biomedicine and Advanced Technologies Rieti Center, Sabina Universitas, Rieti, Italy.,Department of Experimental Medicine, Sapienza University, Rome, Italy
| | | | - Stefano Martellucci
- Biomedicine and Advanced Technologies Rieti Center, Sabina Universitas, Rieti, Italy.,Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Antonella Capozzi
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Elisabetta Mantuano
- Department of Experimental Medicine, Sapienza University, Rome, Italy.,Department of Pathology, University of California at San Diego, La Jolla, CA, USA
| | - Agostina Longo
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Alberto Ferri
- Institute of Cell Biology and Neurobiology, CNR, Rome, Italy.,Fondazione Santa Lucia IRCCS, c/o CERC, Rome, Italy
| | - Tina Garofalo
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Maurizio Sorice
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Roberta Misasi
- Department of Experimental Medicine, Sapienza University, Rome, Italy
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Abstract
The biochemical essence of prion replication is the molecular multiplication of the disease-associated misfolded isoform of prion protein (PrP), termed PrPSc, in a nucleic acid-free manner. PrP(Sc) is generated by the protein misfolding process facilitated by conformational conversion of the host-encoded cellular PrP to PrP(Sc). Evidence suggests that an auxiliary factor may play a role in PrP(Sc) propagation. We and others previously discovered that plasminogen interacts with PrP, while its functional role for PrPSc propagation remained undetermined. In our recent in vitro PrP conversion study, we showed that plasminogen substantially stimulates PrP(Sc) propagation in a concentration-dependent manner by accelerating the rate of PrP(Sc) generation, while depletion of plasminogen, destabilization of its structure, and interference with the PrP-plasminogen interaction hinder PrP(Sc) propagation. Further investigation in cell culture models confirmed an increase of PrP(Sc) formation by plasminogen. Although molecular basis of the observed activity for plasminogen remain to be addressed, our results demonstrate that plasminogen is the first cellular protein auxiliary factor proven to stimulate PrP(Sc) propagation.
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Affiliation(s)
- Charles E Mays
- Department of Microbiology, Immunology and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, KY, USA
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5
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Mays CE, Ryou C. Plasminogen stimulates propagation of protease‐resistant prion protein
in vitro. FASEB J 2010. [DOI: 10.1096/fj.10.163600] [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]
Affiliation(s)
- Charles E. Mays
- Sanders‐Brown Center on AgingDepartment of MicrobiologyImmunology and Molecular GeneticsUniversity of Kentucky College of Medicine Lexington Kentucky USA
| | - Chongsuk Ryou
- Sanders‐Brown Center on AgingDepartment of MicrobiologyImmunology and Molecular GeneticsUniversity of Kentucky College of Medicine Lexington Kentucky USA
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6
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Mays CE, Ryou C. Plasminogen stimulates propagation of protease-resistant prion protein in vitro. FASEB J 2010; 24:5102-12. [PMID: 20732953 DOI: 10.1096/fj.10-163600] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To clarify the role of plasminogen as a cofactor for prion propagation, we conducted functional assays using a cell-free prion protein (PrP) conversion assay termed protein misfolding cyclic amplification (PMCA) and prion-infected cell lines. Here, we report that plasminogen stimulates propagation of the protease-resistant scrapie PrP (PrP(Sc)). Compared to control PMCA conducted without plasminogen, addition of plasminogen in PMCA using wild-type brain material significantly increased PrP conversion, with an EC(50) = ∼56 nM. PrP conversion in PMCA was substantially less efficient with plasminogen-deficient brain material than with wild-type material. The activity stimulating PrP conversion was specific for plasminogen and conserved in its kringle domains. Such activity was abrogated by modification of plasminogen structure and interference of PrP-plasminogen interaction. Kinetic analysis of PrP(Sc) generation demonstrated that the presence of plasminogen in PMCA enhanced the PrP(Sc) production rate to ∼0.97 U/μl/h and reduced turnover time to ∼1 h compared to those (∼0.4 U/μl/h and ∼2.5 h) obtained without supplementation. Furthermore, as observed in PMCA, plasminogen and kringles promoted PrP(Sc) propagation in ScN2a and Elk 21(+) cells. Our results demonstrate that plasminogen functions in stimulating conversion processes and represents the first cellular protein cofactor that enhances the hypothetical mechanism of prion propagation.
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Affiliation(s)
- Charles E Mays
- Sanders-Brown Center on Aging and Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, Lexington, Kentucky, USA
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7
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Cunningham O, Campion S, Perry VH, Murray C, Sidenius N, Docagne F, Cunningham C. Microglia and the urokinase plasminogen activator receptor/uPA system in innate brain inflammation. Glia 2010; 57:1802-14. [PMID: 19459212 PMCID: PMC2816357 DOI: 10.1002/glia.20892] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The urokinase plasminogen activator (uPA) receptor (uPAR) is a GPI-linked cell surface protein that facilitates focused plasmin proteolytic activity at the cell surface. uPAR has been detected in macrophages infiltrating the central nervous system (CNS) and soluble uPAR has been detected in the cerebrospinal fluid during a number of CNS pathologies. However, its expression by resident microglial cells in vivo remains uncertain. In this work, we aimed to elucidate the murine CNS expression of uPAR and uPA as well as that of tissue plasminogen activator and plasminogen activator inhibitor 1 (PAI-1) during insults generating distinct and well-characterized inflammatory responses; acute intracerebral lipopolysaccharide (LPS), acute kainate-induced neurodegeneration, and chronic neurodegeneration induced by prion disease inoculation. All three insults induced marked expression of uPAR at both mRNA and protein level compared to controls (naïve, saline, or control inoculum-injected). uPAR expression was microglial in all cases. Conversely, uPA transcription and activity was only markedly increased during chronic neurodegeneration. Dissociation of uPA and uPAR levels in acute challenges is suggestive of additional proteolysis-independent roles for uPAR. PAI-1 was most highly expressed upon LPS challenge, whereas tissue plasminogen activator mRNA was constitutively present and less responsive to all insults studied. These data are novel and suggest much wider involvement of the uPAR/uPA system in CNS function and pathology than previously supposed.
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Hatcher K, Zheng J, Chen SG. Cryptic peptides of the kringle domains preferentially bind to disease-associated prion protein. J Alzheimers Dis 2009; 16:421-31. [PMID: 19221431 DOI: 10.3233/jad-2009-0980] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Prion diseases are a group of fatal neurodegenerative disorders characterized by the accumulation of a misfolded form (PrP(Sc)) of the cellular prion protein (PrP(C)) in the brains of affected individuals. The conversion of PrP(C) to PrP(Sc) is thought to involve a change in protein conformation from a normal, primarily alpha-helical structure into a beta-sheet conformer. Few proteins have been identified that differentially interact with the two forms of PrP. It has been reported that plasminogen binds to PrP(Sc) from a variety of prion phenotypes. We have examined potential motifs within the kringle region that may be responsible for binding to PrP. We synthesized 12-15-mer peptides that contain small, repetitive stretches of amino acid residues found within the kringle domains of plasminogen. These synthetic peptides were found to capture PrP(Sc) from the brain homogenates of bovine spongiform encephalopathy affected cattle, chronic wasting disease affected elk, experimental scrapie of hamsters and that of subjects affected by Creutzfeldt-Jakob disease, without binding to PrP(C) in unaffected controls. Therefore, we have identified critical peptide motifs that may be important for protein-protein interactions in prion disease pathogenesis. The ability of these synthetic peptides to bind preferentially to PrP(Sc) suggests a potential application in the diagnosis of prion diseases.
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Affiliation(s)
- Kristen Hatcher
- Department of Pathology and National Prion Disease Pathology Surveillance Center, Case Western Reserve University, Cleveland, OH 44106, USA
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Maas C, Schiks B, Strangi RD, Hackeng TM, Bouma BN, Gebbink MFBG, Bouma B. Identification of fibronectin type I domains as amyloid-binding modules on tissue-type plasminogen activator and three homologs. Amyloid 2008; 15:166-80. [PMID: 18925455 DOI: 10.1080/13506120802193498] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The serine protease tissue-type plasminogen activator (tPA), a key enzyme in hemostasis, is activated by protein aggregates with amyloid-like properties. tPA is implicated in various pathologies, including amyloidoses. A major task is to further elucidate the mechanisms of amyloid pathology. We here show that the fibronectin type I domain of tPA mediates the interaction with amyloid protein aggregates. We found that in contrast to full-length tPA, a deletion-mutant of tPA, lacking the first three N-terminal domains (including the fibronectin type I domain), fails to activate in response to amyloid protein aggregates. Using recombinantly produced domains of tPA in direct binding assays, we subsequently mapped the amyloid-binding region to the fibronectin type I domain. This domain co-localized with congophilic plaques in brain sections from patients with Alzheimer's disease. Fibronectin type I domains from homologous proteases factor XII, hepatocyte growth factor activator and from the extracellular matrix protein fibronectin also bound to aggregated amyloidogenic peptides. Finally, we demonstrated that the isolated fibronectin type I domain inhibits amyloid-induced aggregation of blood platelets. The identification of the fibronectin type I domain as an amyloid-binding module provides new insights into the (patho-) physiological role of tPA and the homologous proteins which may offer new targets for intervention in amyloid pathology.
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Affiliation(s)
- Coen Maas
- Department of Clinical Chemistry and Haematology, University Medical Center Utrecht and Institute for Biomembranes, P O Box 85500, Utrecht, The Netherlands
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10
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Role of the plasminogen activation system in extracellular matrix degradation processes in normal or pathological conditions in sheep. Small Rumin Res 2008. [DOI: 10.1016/j.smallrumres.2007.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Affiliation(s)
- P Hammarström
- IFM-Department of Chemistry, Linköping University, SE-581 83 Linköping, Sweden.
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12
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Barnewitz K, Maringer M, Mitteregger G, Giese A, Bertsch U, Kretzschmar HA. Unaltered prion protein cleavage in plasminogen-deficient mice. Neuroreport 2006; 17:527-30. [PMID: 16543819 DOI: 10.1097/01.wnr.0000209003.55728.ac] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In normal brains and cultured cells, cellular prion protein (PrP) is partially found as N-terminally truncated fragments, designated C1 and C2. The cleavage of recombinant PrP to a fragment corresponding to C1 can be mediated by the protease plasmin (Pln) in vitro, suggesting that plasmin might be responsible for the generation of the C1 fragment in vivo as well. The cleavage pattern of PrP found in both brain lysates and other tissues of plasminogen knock-out mice, however, is unaltered. The presence of C1 fragment in homogenates from plasminogen-deficient mice in a comparable ratio with full-length PrP as can be found in wild-type animals indicates that other proteases in addition to plasmin are responsible for PrP cleavage in vivo.
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Affiliation(s)
- Kathrin Barnewitz
- Center for Neuropathology and Prion Research, Ludwig Maximilians University, Munich, Germany
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