1
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Singh S, Hämäläinen RH. The Roles of Cystatin B in the Brain and Pathophysiological Mechanisms of Progressive Myoclonic Epilepsy Type 1. Cells 2024; 13:170. [PMID: 38247861 PMCID: PMC10814315 DOI: 10.3390/cells13020170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/03/2024] [Accepted: 01/15/2024] [Indexed: 01/23/2024] Open
Abstract
Progressive myoclonic epilepsy type 1 (EPM1) is an autosomal recessive disorder, also known as Unverricht-Lundborg disease (ULD). EPM1 patients suffer from photo-sensitive seizures, stimulus-sensitive myoclonus, nocturnal myoclonic seizures, ataxia and dysarthria. In addition, cerebral ataxia and impaired GABAergic inhibition are typically present. EPM1 is caused by mutations in the Cystatin B gene (CSTB). The CSTB protein functions as an intracellular thiol protease inhibitor and inhibits Cathepsin function. It also plays a crucial role in brain development and regulates various functions in neurons beyond maintaining cellular proteostasis. These include controlling cell proliferation and differentiation, synaptic functions and protection against oxidative stress, likely through regulation of mitochondrial function. Depending on the differentiation stage and status of neurons, the protein localizes either to the cytoplasm, nucleus, lysosomes or mitochondria. Further, CSTB can also be secreted to the extracellular matrix for interneuron rearrangement and migration. In this review, we will review the various functions of CSTB in the brain and discuss the putative pathophysiological mechanism underlying EPM1.
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Affiliation(s)
| | - Riikka H. Hämäläinen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland;
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2
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Contini C, Serrao S, Manconi B, Olianas A, Iavarone F, Guadalupi G, Messana I, Castagnola M, Masullo C, Bizzarro A, Turck CW, Maccarrone G, Cabras T. Characterization of Cystatin B Interactome in Saliva from Healthy Elderly and Alzheimer’s Disease Patients. Life (Basel) 2023; 13:life13030748. [PMID: 36983903 PMCID: PMC10054399 DOI: 10.3390/life13030748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/27/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
Cystatin B is a small, multifunctional protein involved in the regulation of inflammation, innate immune response, and neuronal protection and found highly abundant in the brains of patients with Alzheimer’s disease (AD). Recently, our study demonstrated a significant association between the level of salivary cystatin B and AD. Since the protein is able to establish protein-protein interaction (PPI) in different contexts and aggregation-prone proteins and the PPI networks are relevant for AD pathogenesis, and due to the relevance of finding new AD markers in peripheral biofluids, we thought it was interesting to study the possible involvement of cystatin B in PPIs in saliva and to evaluate differences and similarities between AD and age-matched elderly healthy controls (HC). For this purpose, we applied a co-immunoprecipitation procedure and a bottom-up proteomics analysis to purify, identify, and quantify cystatin B interactors. Results demonstrated for the first time the existence of a salivary cystatin B-linked multi-protein complex composed by 82 interactors and largely expressed in the body. Interactors are involved in neutrophil activation, antimicrobial activity, modulation of the cytoskeleton and extra-cellular matrix (ECM), and glucose metabolism. Preliminary quantitative data showed significantly lower levels of triosophosphate isomerase 1 and higher levels of mucin 7, BPI, and matrix Gla protein in AD with respect to HC, suggesting implications associated with AD of altered glucose metabolism, antibacterial activities, and calcification-associated processes. Data are available via ProteomeXchange with identifiers PXD039286 and PXD030679.
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Affiliation(s)
- Cristina Contini
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
| | - Simone Serrao
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
| | - Barbara Manconi
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
- Correspondence:
| | - Alessandra Olianas
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
| | - Federica Iavarone
- Department of Basic Biotechnological Sciences, Intensive and Perioperative Clinics, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Policlinico Universitario “A. Gemelli” Foundation IRCCS, 00168 Rome, Italy
| | - Giulia Guadalupi
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
| | - Irene Messana
- Istituto di Scienze e Tecnologie Chimiche “Giulio Natta”, Consiglio Nazionale delle Ricerche, 00168 Rome, Italy
| | - Massimo Castagnola
- Proteomics Laboratory, European Center for Brain Research, (IRCCS) Santa Lucia Foundation, 00168 Rome, Italy
| | - Carlo Masullo
- Department of Neuroscience, Neurology Section, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | | | - Christoph W. Turck
- Proteomics and Biomarkers, Max Planck Institute of Psychiatry, 80804 Munich, Germany
| | - Giuseppina Maccarrone
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, 80804 Munich, Germany
| | - Tiziana Cabras
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
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3
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Žerovnik E. Human stefin B: from its structure, folding, and aggregation to its function in health and disease. Front Mol Neurosci 2022; 15:1009976. [PMID: 36340691 PMCID: PMC9634419 DOI: 10.3389/fnmol.2022.1009976] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 09/01/2022] [Indexed: 01/11/2024] Open
Abstract
Mutations in the gene for human stefin B (cystatin B) cause progressive myoclonic epilepsy type 1 (EPM1), a neurodegenerative disorder. The most common change is dodecamer repeats in the promoter region of the gene, though missense and frameshift mutations also appear. Human stefin B primarily acts as a cysteine cathepsin inhibitor, and it also exhibits alternative functions. It plays a protective role against oxidative stress, likely via reducing mitochondrial damage and thus generating fewer mitochondrial reactive oxygen species (ROS). Accordingly, lack of stefin B results in increased inflammation and NLRP3 inflammasome activation, producing more ROS. The protein is cytosolic but also has an important role in the nucleus, where it prevents cleavage of the N terminal part of histone 3 by inhibiting cathepsins L and B and thus regulates transcription and cell cycle. Furthermore, it has been shown that stefin B is oligomeric in cells and that it has a specific role in the physiology of the synapse and in vesicular transport. On the basis of my research team's data on the structure, folding, and aggregation of stefin B, we have proposed that it might regulate proteostasis, possessing a chaperone-like function. In this review, I synthesize these observations and derive some conclusions on possible sources of EPM1 pathology. The interaction partners of stefin B and other gene mutations leading to EPM1-like pathology are discussed and common pathways are pinpointed.
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Affiliation(s)
- Eva Žerovnik
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
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4
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Extracellular alpha-synuclein: Sensors, receptors, and responses. Neurobiol Dis 2022; 168:105696. [DOI: 10.1016/j.nbd.2022.105696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 02/28/2022] [Accepted: 03/15/2022] [Indexed: 11/19/2022] Open
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5
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Jahić Mujkić A, Tušek Žnidarič M, Berbić S, Žerovnik E. Synergy of the Inhibitory Action of Polyphenols Plus Vitamin C on Amyloid Fibril Formation: Case Study of Human Stefin B. Antioxidants (Basel) 2021; 10:1471. [PMID: 34573102 PMCID: PMC8464686 DOI: 10.3390/antiox10091471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 12/06/2022] Open
Abstract
In order to study how polyphenols and vitamin C (vitC) together affect protein aggregation to amyloid fibrils, we performed similar in vitro studies as before using stefin B as a model and a potentially amyloid-forming protein (it aggregates upon overexpression, under stressful conditions and some progressive myoclonus epilepsy of tape 1-EPM1-missense mutations). In addition to the chosen polyphenol, this time, we added a proven antioxidant concentration of 0.5 mM vitC into the fibrillation mixture and varied concentrations of resveratrol, quercetin, and curcumin. Synergy with vitC was observed with curcumin and quercetin.
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Affiliation(s)
- Alma Jahić Mujkić
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
- Department of Biochemistry, Faculty of Pharmacy, University of Tuzla, Univerzitetska 1, 75000 Tuzla, Bosnia and Herzegovina; (A.J.M.); (S.B.)
| | - Magda Tušek Žnidarič
- Department of Biotechnology and Systems Biology, National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia;
| | - Selma Berbić
- Department of Biochemistry, Faculty of Pharmacy, University of Tuzla, Univerzitetska 1, 75000 Tuzla, Bosnia and Herzegovina; (A.J.M.); (S.B.)
| | - Eva Žerovnik
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia
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6
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Di Matteo F, Pipicelli F, Kyrousi C, Tovecci I, Penna E, Crispino M, Chambery A, Russo R, Ayo-Martin AC, Giordano M, Hoffmann A, Ciusani E, Canafoglia L, Götz M, Di Giaimo R, Cappello S. Cystatin B is essential for proliferation and interneuron migration in individuals with EPM1 epilepsy. EMBO Mol Med 2020; 12:e11419. [PMID: 32378798 PMCID: PMC7278547 DOI: 10.15252/emmm.201911419] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 12/18/2022] Open
Abstract
Progressive myoclonus epilepsy (PME) of Unverricht–Lundborg type (EPM1) is an autosomal recessive neurodegenerative disorder with the highest incidence of PME worldwide. Mutations in the gene encoding cystatin B (CSTB) are the primary genetic cause of EPM1. Here, we investigate the role of CSTB during neurogenesis in vivo in the developing mouse brain and in vitro in human cerebral organoids (hCOs) derived from EPM1 patients. We find that CSTB (but not one of its pathological variants) is secreted into the mouse cerebral spinal fluid and the conditioned media from hCOs. In embryonic mouse brain, we find that functional CSTB influences progenitors’ proliferation and modulates neuronal distribution by attracting interneurons to the site of secretion via cell‐non‐autonomous mechanisms. Similarly, in patient‐derived hCOs, low levels of functional CSTB result in an alteration of progenitor's proliferation, premature differentiation, and changes in interneurons migration. Secretion and extracellular matrix organization are the biological processes particularly affected as suggested by a proteomic analysis in patients’ hCOs. Overall, our study sheds new light on the cellular mechanisms underlying the development of EPM1.
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Affiliation(s)
- Francesco Di Matteo
- Max Planck Institute of Psychiatry, Munich, Germany.,International Max Planck Research School for Translational Psychiatry (IMPRS-TP), Munich, Germany
| | - Fabrizia Pipicelli
- Max Planck Institute of Psychiatry, Munich, Germany.,International Max Planck Research School for Translational Psychiatry (IMPRS-TP), Munich, Germany
| | | | - Isabella Tovecci
- Max Planck Institute of Psychiatry, Munich, Germany.,Department of Biology, University Federico II, Naples, Italy
| | - Eduardo Penna
- Department of Biology, University Federico II, Naples, Italy
| | | | - Angela Chambery
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy
| | - Rosita Russo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy
| | - Ane Cristina Ayo-Martin
- Max Planck Institute of Psychiatry, Munich, Germany.,International Max Planck Research School for Translational Psychiatry (IMPRS-TP), Munich, Germany
| | | | | | - Emilio Ciusani
- Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | | | - Magdalena Götz
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universitaet (LMU), Planegg/Martinsried, Germany.,Helmholtz Center Munich, Biomedical Center (BMC), Institute of Stem Cell Research, Planegg/Martinsried, Germany.,SyNergy Excellence Cluster, Munich, Germany
| | - Rossella Di Giaimo
- Max Planck Institute of Psychiatry, Munich, Germany.,Department of Biology, University Federico II, Naples, Italy
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7
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Žerovnik E. Possible Mechanisms by which Stefin B could Regulate Proteostasis and Oxidative Stress. Cells 2019; 8:E70. [PMID: 30669344 PMCID: PMC6357131 DOI: 10.3390/cells8010070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/19/2018] [Accepted: 01/09/2019] [Indexed: 01/19/2023] Open
Abstract
Human stefin B is a protease inhibitor from the family of cystatins. It was reported that it forms oligomers in cells. We have shown that it has a role in cell's response to misfolded proteins. We also have shown that its oligomers bind amyloid-beta (Aβ). Here, we discuss ways, how stefin B could reduce build-up of protein aggregates by other proteins and consequently reduces ROS and, how this might be connected to autophagy. When overexpressed, stefin B forms protein aggregates itself and these protein aggregates induce autophagy. Similarly, cystatin C was shown to bind Aβ and to induce autophagy. It is also suggested how more knowledge about the role of stefin B in a cell's response to misfolded proteins could be used to modulate progressive myoclonus epilepsy of type 1 EPM1 disease.
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Affiliation(s)
- Eva Žerovnik
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
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8
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Stoka V, Turk V, Turk B. Lysosomal cathepsins and their regulation in aging and neurodegeneration. Ageing Res Rev 2016; 32:22-37. [PMID: 27125852 DOI: 10.1016/j.arr.2016.04.010] [Citation(s) in RCA: 223] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 04/12/2016] [Accepted: 04/23/2016] [Indexed: 02/07/2023]
Abstract
Lysosomes and lysosomal hydrolases, including the cathepsins, have been shown to change their properties with aging brain a long time ago, although their function was not really understood. The first biochemical and clinical studies were followed by a major expansion in the last 20 years with the development of animal disease models and new approaches leading to a major advancement of understanding of the role of physiological and degenerative processes in the brain at the molecular level. This includes the understanding of the major role of autophagy and the cathepsins in a number of diseases, including its critical role in the neuronal ceroid lipofuscinosis. Similarly, cathepsins and some other lysosomal proteases were shown to have important roles in processing and/or degradation of several important neuronal proteins, thereby having either neuroprotective or harmful roles. In this review, we discuss lysosomal cathepsins and their regulation with the focus on cysteine cathepsins and their endogenous inhibitors, as well as their role in several neurodegenerative diseases.
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Affiliation(s)
- Veronika Stoka
- Department of Biochemistry and Molecular and Structural Biology, J. Stefan Institute, Jamova 39, Sl-1000 Ljubljana, Slovenia; J. Stefan International Postgraduate School, Jamova 39, Sl-1000 Ljubljana, Slovenia.
| | - Vito Turk
- Department of Biochemistry and Molecular and Structural Biology, J. Stefan Institute, Jamova 39, Sl-1000 Ljubljana, Slovenia; J. Stefan International Postgraduate School, Jamova 39, Sl-1000 Ljubljana, Slovenia
| | - Boris Turk
- Department of Biochemistry and Molecular and Structural Biology, J. Stefan Institute, Jamova 39, Sl-1000 Ljubljana, Slovenia; Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, Sl-1000 Ljubljana, Slovenia; Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Sl-1000 Ljubljana, Slovenia.
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9
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Žerovnik E. Putative alternative functions of human stefin B (cystatin B): binding to amyloid-beta, membranes, and copper. J Mol Recognit 2016; 30. [PMID: 27577977 DOI: 10.1002/jmr.2562] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/17/2022]
Abstract
We describe studies performed thus far on stefin B from the family of cystatins as a model protein for folding and amyloid fibril formation studies. We also briefly mention our studies on aggregation of some of the missense EPM1 mutants of stefin B in cells, which mimic additional pathological traits (gain in toxic function) in selected patients with EPM1 disease. We collected data on the reported interactors of stefin B and discuss several hypotheses of possible cytosolic alternative functions.
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Affiliation(s)
- Eva Žerovnik
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia.,CipKeBip-Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Ljubljana, Slovenia
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10
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Davis PJ, Holmes D, Waltho JP, Staniforth RA. Limited Proteolysis Reveals That Amyloids from the 3D Domain-Swapping Cystatin B Have a Non-Native β-Sheet Topology. J Mol Biol 2015; 427:2418-2434. [DOI: 10.1016/j.jmb.2015.05.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 05/08/2015] [Accepted: 05/15/2015] [Indexed: 01/21/2023]
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11
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Gain in toxic function of stefin B EPM1 mutants aggregates: Correlation between cell death, aggregate number/size and oxidative stress. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:2089-99. [DOI: 10.1016/j.bbamcr.2014.05.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 05/28/2014] [Accepted: 05/29/2014] [Indexed: 11/19/2022]
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12
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Polajnar M, Zavašnik-Bergant T, Škerget K, Vizovišek M, Vidmar R, Fonović M, Kopitar-Jerala N, Petrovič U, Navarro S, Ventura S, Žerovnik E. Human stefin B role in cell's response to misfolded proteins and autophagy. PLoS One 2014; 9:e102500. [PMID: 25047918 PMCID: PMC4105463 DOI: 10.1371/journal.pone.0102500] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 06/18/2014] [Indexed: 11/30/2022] Open
Abstract
Alternative functions, apart from cathepsins inhibition, are being discovered for stefin B. Here, we investigate its role in vesicular trafficking and autophagy. Astrocytes isolated from stefin B knock-out (KO) mice exhibited an increased level of protein aggregates scattered throughout the cytoplasm. Addition of stefin B monomers or small oligomers to the cell medium reverted this phenotype, as imaged by confocal microscopy. To monitor the identity of proteins embedded within aggregates in wild type (wt) and KO cells, the insoluble cell lysate fractions were isolated and analyzed by mass spectrometry. Chaperones, tubulins, dyneins, and proteosomal components were detected in the insoluble fraction of wt cells but not in KO aggregates. In contrast, the insoluble fraction of KO cells exhibited increased levels of apolipoprotein E, fibronectin, clusterin, major prion protein, and serpins H1 and I2 and some proteins of lysosomal origin, such as cathepsin D and CD63, relative to wt astrocytes. Analysis of autophagy activity demonstrated that this pathway was less functional in KO astrocytes. In addition, synthetic dosage lethality (SDL) gene interactions analysis in Saccharomyces cerevisiae expressing human stefin B suggests a role in transport of vesicles and vacuoles These activities would contribute, directly or indirectly to completion of autophagy in wt astrocytes and would account for the accumulation of protein aggregates in KO cells, since autophagy is a key pathway for the clearance of intracellular protein aggregates.
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Affiliation(s)
- Mira Polajnar
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Tina Zavašnik-Bergant
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Katja Škerget
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Department of Molecular and Biomedical Science, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Matej Vizovišek
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Robert Vidmar
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Marko Fonović
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Nataša Kopitar-Jerala
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Uroš Petrovič
- Department of Molecular and Biomedical Science, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Susanna Navarro
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Spain
| | - Salvador Ventura
- Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Spain
| | - Eva Žerovnik
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
- CipKeBip - Center of Excellence for integrated approaches in chemistry and biology of proteins, Ljubljana, Slovenia
- * E-mail:
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13
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Rispoli A, Cipollini E, Catania S, Di Giaimo R, Pulice G, van Houte S, Sparla F, Dal Piaz F, Roncarati D, Trost P, Melli M. Insights in progressive myoclonus epilepsy: HSP70 promotes cystatin B polymerization. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2591-9. [DOI: 10.1016/j.bbapap.2013.09.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 09/16/2013] [Accepted: 09/17/2013] [Indexed: 12/15/2022]
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14
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Cystatin B and SOD1: Protein–Protein Interaction and Possible Relation to Neurodegeneration. Cell Mol Neurobiol 2013; 34:205-13. [DOI: 10.1007/s10571-013-0004-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 11/06/2013] [Indexed: 12/15/2022]
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15
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The role of initial oligomers in amyloid fibril formation by human stefin B. Int J Mol Sci 2013; 14:18362-84. [PMID: 24013380 PMCID: PMC3794784 DOI: 10.3390/ijms140918362] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 02/03/2023] Open
Abstract
Oligomers are commonly observed intermediates at the initial stages of amyloid fibril formation. They are toxic to neurons and cause decrease in neural transmission and long-term potentiation. We describe an in vitro study of the initial steps in amyloid fibril formation by human stefin B, which proved to be a good model system. Due to relative stability of the initial oligomers of stefin B, electrospray ionization mass spectrometry (ESI MS) could be applied in addition to size exclusion chromatography (SEC). These two techniques enabled us to separate and detect distinguished oligomers from the monomers: dimers, trimers, tetramers, up to decamers. The amyloid fibril formation process was followed at different pH and temperatures, including such conditions where the process was slow enough to detect the initial oligomeric species at the very beginning of the lag phase and those at the end of the lag phase. Taking into account the results of the lower-order oligomers transformations early in the process, we were able to propose an improved model for the stefin B fibril formation.
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16
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Polajnar M, Ceru S, Kopitar-Jerala N, Zerovnik E. Human stefin B normal and patho-physiological role: molecular and cellular aspects of amyloid-type aggregation of certain EPM1 mutants. Front Mol Neurosci 2012; 5:88. [PMID: 22936898 PMCID: PMC3426797 DOI: 10.3389/fnmol.2012.00088] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Accepted: 08/03/2012] [Indexed: 11/24/2022] Open
Abstract
Epilepsies are characterized by abnormal electrophysiological activity of the brain. Among various types of inherited epilepsies different epilepsy syndromes, among them progressive myoclonus epilepsies with features of ataxia and neurodegeneration, are counted. The progressive myoclonus epilepsy of type 1 (EPM1), also known as Unverricht-Lundborg disease presents with features of cerebellar atrophy and increased oxidative stress. It has been found that EPM1 is caused by mutations in human cystatin B gene (human stefin B). We first describe the role of protein aggregation in other neurodegenerative conditions. Protein aggregates appear intraneurally but are also excreted, such as is the case with senile plaques of amyloid-β (Aβ) that accumulate in the brain parenchyma and vessel walls. A common characteristic of such diseases is the change of the protein conformation toward β secondary structure that accounts for the strong tendency of such proteins to aggregate and form amyloid fibrils. Second, we describe the patho-physiology of EPM1 and the normal and aberrant roles of stefin B in a mouse model of the disease. Furthermore, we discuss how the increased protein aggregation observed with some of the mutants of human stefin B may relate to the neurodegeneration that occurs in rare EPM1 patients. Our hypothesis (Ceru et al., 2005) states that some of the EPM1 mutants of human stefin B may undergo aggregation in neural cells, thus gaining additional toxic function (apart from loss of normal function). Our in vitro experiments thus far have confirmed that four mutants undergo increased aggregation relative to the wild-type protein. It has been shown that the R68X mutant forms amyloid-fibrils very rapidly, even at neutral pH and forms perinuclear inclusions, whereas the G4R mutant exhibits a prolonged lag phase, during which the toxic prefibrillar aggregates accumulate and are scattered more diffusely over the cytoplasm. Initial experiments on the G50E and Q71P missense EPM1 mutants are described.
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Affiliation(s)
- Mira Polajnar
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute Ljubljana, Slovenia
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Anderluh G, Zerovnik E. Pore formation by human stefin B in its native and oligomeric states and the consequent amyloid induced toxicity. Front Mol Neurosci 2012; 5:85. [PMID: 22876218 PMCID: PMC3410518 DOI: 10.3389/fnmol.2012.00085] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 07/17/2012] [Indexed: 11/13/2022] Open
Abstract
It is well documented that amyloid forming peptides and proteins interact with membranes and that this correlates with cytotoxicity. To introduce the theme we give a brief description of some amyloidogenic proteins and note their similarities with pore forming toxins (PFTs) and cell penetrating peptides. Human stefin B, a member of the family of cystatins, is an amyloidogenic protein in vitro. This review describes our studies of the interaction of stefin B oligomers and prefibrillar aggregates with model membranes leading to pore formation. We have studied the interaction between human stefin B and artificial membranes of various compositions. We also have prepared distinct sizes and morphologies of stefin B prefibrillar states and assessed their toxicity. Furthermore, we have measured electrical currents through pores formed by stefin B prefibrillar oligomers in a planar lipid bilayer setup. We finally discuss the possible functional and pathological significance of such pores formed by human stefin B.
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Brault V, Martin B, Costet N, Bizot JC, Hérault Y. Characterization of PTZ-induced seizure susceptibility in a down syndrome mouse model that overexpresses CSTB. PLoS One 2011; 6:e27845. [PMID: 22140471 PMCID: PMC3227573 DOI: 10.1371/journal.pone.0027845] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 10/26/2011] [Indexed: 12/27/2022] Open
Abstract
Down syndrome (DS) is a complex genetic syndrome characterized by intellectual disability, dysmorphism and variable additional physiological traits. Current research progress has begun to decipher the neural mechanisms underlying cognitive impairment, leading to new therapeutic perspectives. Pentylenetetrazol (PTZ) has recently been found to have positive effects on learning and memory capacities of a DS mouse model and is foreseen to treat DS patients. But PTZ is also known to be a convulsant drug at higher dose and DS persons are more prone to epileptic seizures than the general population. This raises concerns over what long-term effects of treatment might be in the DS population. The cause of increased propensity for epilepsy in the DS population and which Hsa21 gene(s) are implicated remain unknown. Among Hsa21 candidate genes in epilepsy, CSTB, coding for the cystein protease inhibitor cystatin B, is involved in progressive myoclonus epilepsy and ataxia in both mice and human. Thus we aim to evaluate the effect of an increase in Cstb gene dosage on spontaneous epileptic activity and susceptibility to PTZ-induced seizure. To this end we generated a new mouse model trisomic for Cstb by homologous recombination. We verified that increasing copy number of Cstb from Trisomy (Ts) to Tetrasomy (Tt) was driving overexpression of the gene in the brain, we checked transgenic animals for presence of locomotor activity and electroencephalogram (EEG) abnormalities characteristic of myoclonic epilepsy and we tested if those animals were prone to PTZ-induced seizure. Overall, the results of the analysis shows that an increase in Cstb does not induce any spontaneous epileptic activity and neither increase or decrease the propensity of Ts and Tt mice to myoclonic seizures suggesting that Ctsb dosage should not interfere with PTZ-treatment.
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Affiliation(s)
- Véronique Brault
- Department of Translational Medicine and Neurogenetics, Institut de Génétique Biologie Moléculaire et Cellulaire (IGBMC), Inserm U596, CNRS UMR7104, Université de Strasbourg, Illkirch, France
| | - Benoît Martin
- Inserm U642, Rennes, France
- Laboratoire Traitement du Signal et de l'Image, Université de Rennes 1, Rennes, France
| | - Nathalie Costet
- Inserm U642, Rennes, France
- Laboratoire Traitement du Signal et de l'Image, Université de Rennes 1, Rennes, France
| | | | - Yann Hérault
- Department of Translational Medicine and Neurogenetics, Institut de Génétique Biologie Moléculaire et Cellulaire (IGBMC), Inserm U596, CNRS UMR7104, Université de Strasbourg, Illkirch, France
- Transgenese et Archivage Animaux Modèles, TAAM, CNRS, UPS44, Orléans, France
- Institut Français Clinique de la Souris, GIE CERBM, Illkirch, France
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Polajnar M, Žerovnik E. Impaired autophagy: a link between neurodegenerative diseases and progressive myoclonus epilepsies. Trends Mol Med 2011; 17:293-300. [DOI: 10.1016/j.molmed.2011.02.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 02/22/2011] [Accepted: 02/25/2011] [Indexed: 01/29/2023]
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Yang DS, Stavrides P, Mohan PS, Kaushik S, Kumar A, Ohno M, Schmidt SD, Wesson D, Bandyopadhyay U, Jiang Y, Pawlik M, Peterhoff CM, Yang AJ, Wilson DA, St George-Hyslop P, Westaway D, Mathews PM, Levy E, Cuervo AM, Nixon RA. Reversal of autophagy dysfunction in the TgCRND8 mouse model of Alzheimer's disease ameliorates amyloid pathologies and memory deficits. ACTA ACUST UNITED AC 2011; 134:258-77. [PMID: 21186265 DOI: 10.1093/brain/awq341] [Citation(s) in RCA: 333] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Autophagy, a major degradative pathway for proteins and organelles, is essential for survival of mature neurons. Extensive autophagic-lysosomal pathology in Alzheimer's disease brain contributes to Alzheimer's disease pathogenesis, although the underlying mechanisms are not well understood. Here, we identified and characterized marked intraneuronal amyloid-β peptide/amyloid and lysosomal system pathology in the Alzheimer's disease mouse model TgCRND8 similar to that previously described in Alzheimer's disease brains. We further establish that the basis for these pathologies involves defective proteolytic clearance of neuronal autophagic substrates including amyloid-β peptide. To establish the pathogenic significance of these abnormalities, we enhanced lysosomal cathepsin activities and rates of autophagic protein turnover in TgCRND8 mice by genetically deleting cystatin B, an endogenous inhibitor of lysosomal cysteine proteases. Cystatin B deletion rescued autophagic-lysosomal pathology, reduced abnormal accumulations of amyloid-β peptide, ubiquitinated proteins and other autophagic substrates within autolysosomes/lysosomes and reduced intraneuronal amyloid-β peptide. The amelioration of lysosomal function in TgCRND8 markedly decreased extracellular amyloid deposition and total brain amyloid-β peptide 40 and 42 levels, and prevented the development of deficits of learning and memory in fear conditioning and olfactory habituation tests. Our findings support the pathogenic significance of autophagic-lysosomal dysfunction in Alzheimer's disease and indicate the potential value of restoring normal autophagy as an innovative therapeutic strategy for Alzheimer's disease.
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Affiliation(s)
- Dun-Sheng Yang
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY 10962, USA.
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Taler-Verčič A, Zerovnik E. Binding of amyloid peptides to domain-swapped dimers of other amyloid-forming proteins may prevent their neurotoxicity. Bioessays 2010; 32:1020-4. [PMID: 21086533 DOI: 10.1002/bies.201000079] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ajda Taler-Verčič
- Department of Biochemistry, Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
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Zerovnik E, Staniforth RA, Turk D. Amyloid fibril formation by human stefins: Structure, mechanism & putative functions. Biochimie 2010; 92:1597-607. [PMID: 20685229 DOI: 10.1016/j.biochi.2010.05.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 05/20/2010] [Indexed: 11/26/2022]
Abstract
Many questions in the field of protein aggregation to amyloid fibrils remain open. In this review we describe predominantly in vitro studies of oligomerization and amyloid fibril formation by human stefins A and B. In human stefin B amyloidogenesis in vitro we have observed some general and many specific properties of its prefibrillar oligomers and amyloid fibrils. One characteristic feature in common to stefins and cystatins (and possibly some other amyloid proteins) is domain-swapping. In addition to solution structure of the domain-swapped dimer of stefin A, we recently have determined 3D structure of stefin B tetramer, which proved to be composed from two domain-swapped dimers, whose interaction occurs by a proline switch in the loop surrounding the conserved Pro 74. Studying the mechanism of fibril formation by stefin B, we found that the nucleation and fibril elongation reactions have energies of activation (E(a)'s) in the range of proline isomerisation, strongly indicating importance of the Pro at site 74 and/or other prolines in the sequence. Correlation between toxicity of the prefibrillar oligomers and their interaction with acidic phospholipids was demonstrated. Stefin B was shown to interact with amyloid-beta peptide of Alzheimer's disease in an oligomer specific manner, both in vitro and in the cells. It also has been shown that endogenous stefin B (with E at site 31) but especially the EPM1 mutant R68X and Y31-stefin B variant, and to a lesser extent EPM1 mutant G4R, are prone to form aggregates in cells.
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Affiliation(s)
- Eva Zerovnik
- Department of Biochemistry, Molecular and Structural Biology, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
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Intracellular aggregation of human stefin B: confocal and electron microscopy study. Biol Cell 2010; 102:319-34. [PMID: 20078424 DOI: 10.1042/bc20090163] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Protein aggregation is a major contributor to the pathogenic mechanisms of human neurodegenerative diseases. Mutations in the CSTB (cystatin B) gene [StB (stefin B)] cause EPM1 (progressive myoclonus epilepsy of type 1), an epilepsy syndrome with features of neurodegeneration and increased oxidative stress. Oligomerization and aggregation of StB in mammalian cells have recently been reported. It has also been observed that StB is overexpressed after seizures and in certain neurodegenerative conditions, which could potentially lead to its aggregation. Human StB proved to be a good model system to study amyloid fibril formation in vitro and, as we show here, to study protein aggregation in cells. RESULTS Endogenous human StB formed smaller, occasional cytoplasmic aggregates and chemical inhibition of the UPS (ubiquitin-proteasome system) led to an increase in the amount of the endogenous protein and also increased its aggregation. Further, we characterized both the untagged and T-Sapphire-tagged StB on overexpression in mammalian cells. Compared with wild-type StB, the EPM1 missense mutant (G4R), the aggregate-prone EPM1 mutant (R68X) and the Y31 StB variant (both tagged and untagged) formed larger cytosolic and often perinuclear aggregates accompanied by cytoskeletal reorganization. Non-homogeneous morphology of these large aggregates was revealed using TEM (transmission electron microscopy) with StB detected by immunogold labelling. StB-positive cytoplasmic aggregates were partially co-localized with ubiquitin, proteasome subunits S20 and S26 and components of microfilament and microtubular cytoskeleton using confocal microscopy. StB aggregates also co-localized with LC3 and the protein adaptor p62, markers of autophagy. Flow cytometry showed that protein aggregation was associated with reduced cell viability. CONCLUSIONS We have shown that endogenous StB aggregates within cells, and that aggregation is increased upon protein overexpression or proteasome inhibition. From confocal and TEM analyses, we conclude that aggregates of StB show some of the molecular characteristics of aggresomes and may be eliminated from the cell by autophagy. Intracellular StB aggregation shows a negative correlation with cell survival.
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Skerget K, Taler-Vercic A, Bavdek A, Hodnik V, Ceru S, Tusek-Znidaric M, Kumm T, Pitsi D, Pompe-Novak M, Palumaa P, Soriano S, Kopitar-Jerala N, Turk V, Anderluh G, Zerovnik E. Interaction between oligomers of stefin B and amyloid-beta in vitro and in cells. J Biol Chem 2009; 285:3201-10. [PMID: 19955183 DOI: 10.1074/jbc.m109.024620] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To contribute to the question of the putative role of cystatins in Alzheimer disease and in neuroprotection in general, we studied the interaction between human stefin B (cystatin B) and amyloid-beta-(1-40) peptide (Abeta). Using surface plasmon resonance and electrospray mass spectrometry we were able to show a direct interaction between the two proteins. As an interesting new fact, we show that stefin B binding to Abeta is oligomer specific. The dimers and tetramers of stefin B, which bind Abeta, are domain-swapped as judged from structural studies. Consistent with the binding results, the same oligomers of stefin B inhibit Abeta fibril formation. When expressed in cultured cells, stefin B co-localizes with Abeta intracellular inclusions. It also co-immunoprecipitates with the APP fragment containing the Abeta epitope. Thus, stefin B is another APP/Abeta-binding protein in vitro and likely in cells.
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Affiliation(s)
- Katja Skerget
- Department of Biochemistry, Molecular and Structural Biology, JoZef Stefan Institute, Jamova 39, Slovenia
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