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Bharadwaj AG, Okura GC, Woods JW, Allen EA, Miller VA, Kempster E, Hancock MA, Gujar S, Slibinskas R, Waisman DM. Identification and characterization of calreticulin as a novel plasminogen receptor. J Biol Chem 2024; 300:105465. [PMID: 37979915 PMCID: PMC10770727 DOI: 10.1016/j.jbc.2023.105465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 10/22/2023] [Accepted: 11/06/2023] [Indexed: 11/20/2023] Open
Abstract
Calreticulin (CRT) was originally identified as a key calcium-binding protein of the endoplasmic reticulum. Subsequently, CRT was shown to possess multiple intracellular functions, including roles in calcium homeostasis and protein folding. Recently, several extracellular functions have been identified for CRT, including roles in cancer cell invasion and phagocytosis of apoptotic and cancer cells by macrophages. In the current report, we uncover a novel function for extracellular CRT and report that CRT functions as a plasminogen-binding receptor that regulates the conversion of plasminogen to plasmin. We show that human recombinant or bovine tissue-derived CRT dramatically stimulated the conversion of plasminogen to plasmin by tissue plasminogen activator or urokinase-type plasminogen activator. Surface plasmon resonance analysis revealed that CRT-bound plasminogen (KD = 1.8 μM) with moderate affinity. Plasminogen binding and activation by CRT were inhibited by ε-aminocaproic acid, suggesting that an internal lysine residue of CRT interacts with plasminogen. We subsequently show that clinically relevant CRT variants (lacking four or eight lysines in carboxyl-terminal region) exhibited decreased plasminogen activation. Furthermore, CRT-deficient fibroblasts generated 90% less plasmin and CRT-depleted MDA MB 231 cells also demonstrated a significant reduction in plasmin generation. Moreover, treatment of fibroblasts with mitoxantrone dramatically stimulated plasmin generation by WT but not CRT-deficient fibroblasts. Our results suggest that CRT is an important cellular plasminogen regulatory protein. Given that CRT can empower cells with plasmin proteolytic activity, this discovery may provide new mechanistic insight into the established role of CRT in cancer.
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Affiliation(s)
- Alamelu G Bharadwaj
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada; Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Gillian C Okura
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - John W Woods
- Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Erica A Allen
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Victoria A Miller
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Emma Kempster
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Mark A Hancock
- McGill SPR-MS Facility, McGill University, Montréal, Québec, Canada
| | - Shashi Gujar
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Rimantas Slibinskas
- Life Sciences Center, Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | - David M Waisman
- Departments of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada; Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.
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Lu A, Pallero MA, Owusu BY, Borovjagin AV, Lei W, Sanders PW, Murphy-Ullrich JE. Calreticulin is important for the development of renal fibrosis and dysfunction in diabetic nephropathy. Matrix Biol Plus 2020; 8:100034. [PMID: 33543033 PMCID: PMC7852315 DOI: 10.1016/j.mbplus.2020.100034] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/13/2020] [Accepted: 03/20/2020] [Indexed: 12/14/2022] Open
Abstract
Previously, our lab showed that the endoplasmic reticulum (ER) and calcium regulatory protein, calreticulin (CRT), is important for collagen transcription, secretion, and assembly into the extracellular matrix (ECM) and that ER CRT is critical for TGF-β stimulation of type I collagen transcription through stimulation of ER calcium release and NFAT activation. Diabetes is the leading cause of end stage renal disease. TGF-β is a key factor in the pathogenesis of diabetic nephropathy. However, the role of calreticulin (Calr) in fibrosis of diabetic nephropathy has not been investigated. In current work, we used both in vitro and in vivo approaches to assess the role of ER CRT in TGF-β and glucose stimulated ECM production by renal tubule cells and in diabetic mice. Knockdown of CALR by siRNA in a human proximal tubular cell line (HK-2) showed reduced induction of soluble collagen when stimulated by TGF-β or high glucose as compared to control cells, as well as a reduction in fibronectin and collagen IV transcript levels. CRT protein is increased in kidneys of mice made diabetic with streptozotocin and subjected to uninephrectomy to accelerate renal tubular injury as compared to controls. We used renal-targeted ultrasound delivery of Cre-recombinase plasmid to knockdown specifically CRT expression in the remaining kidney of uninephrectomized Calr fl/fl mice with streptozotocin-induced diabetes. This approach reduced CRT expression in the kidney, primarily in the tubular epithelium, by 30-55%, which persisted over the course of the studies. Renal function as measured by the urinary albumin/creatinine ratio was improved in the mice with knockdown of CRT as compared to diabetic mice injected with saline or subjected to ultrasound and injected with control GFP plasmid. PAS staining of kidneys and immunohistochemical analyses of collagen types I and IV show reduced glomerular and tubulointerstitial fibrosis. Renal sections from diabetic mice with CRT knockdown showed reduced nuclear NFAT in renal tubules and treatment of diabetic mice with 11R-VIVIT, an NFAT inhibitor, reduced proteinuria and renal fibrosis. These studies identify ER CRT as an important regulator of TGF-β stimulated ECM production in the diabetic kidney, potentially through regulation of NFAT-dependent ECM transcription.
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Key Words
- 4-PBA, 4-phenylbutyrate
- CRT, calreticulin
- Calreticulin
- Collagen
- Diabetic nephropathy
- ECM, extracellular matrix
- EMT, epithelial to mesenchymal transition
- ER, endoplasmic reticulum
- Fibrosis
- GRP78, glucose related protein 78
- MB/US, microbubble/ultrasound
- NFAT
- NFAT, nuclear factor of activated T cells
- PAS, Periodic Acid-Schiff
- STZ, streptozotocin
- TGF-β, transforming growth factor-β
- UPR, unfolded protein response
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Affiliation(s)
- Ailing Lu
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294-0019, USA
| | - Manuel A. Pallero
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294-0019, USA
| | - Benjamin Y. Owusu
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294-0019, USA
| | - Anton V. Borovjagin
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294-0019, USA
| | - Weiqi Lei
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294-0019, USA
| | - Paul W. Sanders
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294-0019, USA
- Department of Veterans Affairs Medical Center, Birmingham, AL 35233, USA
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Kotian V, Sarmah D, Kaur H, Kesharwani R, Verma G, Mounica L, Veeresh P, Kalia K, Borah A, Wang X, Dave KR, Yavagal DR, Bhattacharya P. Evolving Evidence of Calreticulin as a Pharmacological Target in Neurological Disorders. ACS Chem Neurosci 2019; 10:2629-2646. [PMID: 31017385 DOI: 10.1021/acschemneuro.9b00158] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Calreticulin (CALR), a lectin-like ER chaperone, was initially known only for its housekeeping function, but today it is recognized for many versatile roles in different compartments of a cell. Apart from canonical roles in protein folding and calcium homeostasis, it performs a variety of noncanonical roles, mostly in CNS development. In the past, studies have linked Calreticulin with various other biological components which are detrimental in deciding the fate of neurons. Many neurological disorders that differ in their etiology are commonly associated with aberrant levels of Calreticulin, that lead to modulation of apoptosis and phagocytosis, and impact on transcriptional pathways, impairment in proteostatis, and calcium imbalances. Such multifaceted properties of Calreticulin are the reason why it has been implicated in vital roles of the nervous system in recent years. Hence, understanding its role in the physiology of neurons would help to unearth its involvement in the spectrum of neurological disorders. This Review aims toward exploring the interplay of Calreticulin in neurological disorders which would aid in targeting Calreticulin for developing novel neurotherapeutics.
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Affiliation(s)
- Vignesh Kotian
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Deepaneeta Sarmah
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Harpreet Kaur
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Radhika Kesharwani
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Geetesh Verma
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Leela Mounica
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Pabbala Veeresh
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Kiran Kalia
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Anupom Borah
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam 788011, India
| | - Xin Wang
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Kunjan R. Dave
- Department of Neurology, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
| | - Dileep R. Yavagal
- Department of Neurology and Neurosurgery, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
| | - Pallab Bhattacharya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat 382355, India
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Owusu BY, Zimmerman KA, Murphy-Ullrich JE. The role of the endoplasmic reticulum protein calreticulin in mediating TGF-β-stimulated extracellular matrix production in fibrotic disease. J Cell Commun Signal 2017; 12:289-299. [PMID: 29080087 DOI: 10.1007/s12079-017-0426-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 12/11/2022] Open
Abstract
Endoplasmic reticulum (ER) stress is a key factor contributing to fibrotic disease. Although ER stress is a short-term adaptive response, with chronic stimulation, it can activate pathways leading to fibrosis. ER stress can induce TGF-β signaling, a central driver of extracellular matrix production in fibrosis. This review will discuss the role of an ER protein, calreticulin (CRT), which has both chaperone and calcium regulatory functions, in fibrosis. CRT expression is upregulated in multiple different fibrotic diseases. The roles of CRT in regulation of fibronectin extracellular matrix assembly, extracellular matrix transcription, and collagen secretion and processing into the extracellular matrix will be discussed. Evidence for the importance of CRT in ER calcium release and NFAT activation downstream of TGF-β signaling will be presented. Finally, we will summarize evidence from animal models in which CRT expression is genetically reduced or experimentally downregulated in targeted tissues of adult animals and discuss how these models define a key role for CRT in fibrotic diseases.
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Affiliation(s)
- Benjamin Y Owusu
- Department of Pathology, University of Alabama at Birmingham, G001A Volker Hall, Birmingham, AL, 35294, USA
| | - Kurt A Zimmerman
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Joanne E Murphy-Ullrich
- Department of Pathology, University of Alabama at Birmingham, G001A Volker Hall, Birmingham, AL, 35294, USA. .,Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
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5
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Migliaccio AR, Uversky VN. Dissecting physical structure of calreticulin, an intrinsically disordered Ca 2+-buffering chaperone from endoplasmic reticulum. J Biomol Struct Dyn 2017; 36:1617-1636. [PMID: 28504081 DOI: 10.1080/07391102.2017.1330224] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Calreticulin (CALR) is a Ca2+ binding multifunctional protein that mostly resides in the endoplasmic reticulum (ER) and plays a number of important roles in various physiological and pathological processes. Although the major functions ascribed to CALR are controlling the Ca2+ homeostasis in ER and acting as a lectin-like ER chaperon for many glycoproteins, this moonlighting protein can be found in various cellular compartments where it has many non-ER functions. To shed more light on the mechanisms underlying polyfunctionality of this moonlighting protein that can be found in different cellular compartments and that possesses a wide spectrum of unrelated biological activities, being able to interact with Ca2+ (and potentially other metal ions), RNA, oligosaccharides, and numerous proteins, we used a set of experimental and computational tools to evaluate the intrinsic disorder status of CALR and the role of calcium binding on structural properties and conformational stability of the full-length CALR and its isolated P- and C-domains.
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Affiliation(s)
- Anna Rita Migliaccio
- a Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai (ISMMS) , New York , NY , USA.,b Department of Biomedical and Neuromotorial Sciences , Alma Mater University , Bologna , Italy
| | - Vladimir N Uversky
- c Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute , Morsani College of Medicine, University of South Florida , Tampa , FL , USA.,d Laboratory of New Methods in Biology , Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
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6
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Sánchez D, Gregor P, Čurila K, Hoffmanová I, Hábová V, Tučková L, Tlaskalová-Hogenová H. Anti-calreticulin antibodies and calreticulin in sera of patients diagnosed with dilated or hypertrophic cardiomyopathy. Autoimmunity 2016; 49:554-562. [PMID: 27689957 DOI: 10.1080/08916934.2016.1214822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Distinct cellular level of the Ca2+-binding chaperone calreticulin (CRT) is essential for correct embryonal cardiac development and postnatal function. However, CRT is also a potential autoantigen eliciting formation of antibodies (Ab), whose role is not yet clarified. Immunization with CRT leads to cardiac injury, while overexpression of CRT in cardiomyocytes induces dilated cardiomyopathy (DCM) in animals. Hence, we analysed levels of anti-CRT Ab and calreticulin in the sera of patients with idiopatic DCM and hypertrophic cardiomyopathy (HCM). ELISA and immunoblot using human recombinant CRT and Pepscan with synthetic, overlapping decapeptides of CRT were used to detect anti-CRT Ab. Serum CRT concentration was tested by ELISA. Significantly increased levels of anti-CRT Ab of isotypes IgA (p < 0.001) and IgG (p < 0.05) were found in patients with both DCM (12/34 seropositive for IgA, 7/34 for IgG) and HCM (13/38 seropositive for IgA, 11/38 for IgG) against healthy controls (2/79 for IgA, 1/79 for IgG). Titration analysis in seropositive DCM and HCM patients documented anti-CRT Ab detected at 1/1600 dilution for IgG and 1/800 for IgA (and IgA1) and at least at 1/200 dilution for IgA2, IgG1, IgG2 and IgG3. Pepscan identified immunogenic CRT epitopes recognized by IgA and IgG Ab of these patients. Significantly increased levels of CRT relative to healthy controls were found in sera of patients with HCM (p < 0.01, 5/19). These data extend the knowledge of seroprevalence of anti-CRT Ab and CRT, and suggest possible involvement of autoimmune mechanisms directed to CRT in some forms of cardiomyopathies, which are clinically heterogeneous.
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Affiliation(s)
- Daniel Sánchez
- a Laboratory of Cellular and Molecular Immunology , Institute of Microbiology v.v.i, Czech Academy of Sciences , Prague , Czech Republic
| | - Pavel Gregor
- b Cardiocenter, Department of Cardiology, Third Faculty of Medicine, Charles University in Prague and University Hospital Královské Vinohrady , Prague , Czech Republic , and
| | - Karol Čurila
- b Cardiocenter, Department of Cardiology, Third Faculty of Medicine, Charles University in Prague and University Hospital Královské Vinohrady , Prague , Czech Republic , and
| | - Iva Hoffmanová
- c Second Department of Internal Medicine, Third Faculty of Medicine, Charles University in Prague and University Hospital Královské Vinohrady , Prague , Czech Republic
| | - Věra Hábová
- a Laboratory of Cellular and Molecular Immunology , Institute of Microbiology v.v.i, Czech Academy of Sciences , Prague , Czech Republic
| | - Ludmila Tučková
- a Laboratory of Cellular and Molecular Immunology , Institute of Microbiology v.v.i, Czech Academy of Sciences , Prague , Czech Republic
| | - Helena Tlaskalová-Hogenová
- a Laboratory of Cellular and Molecular Immunology , Institute of Microbiology v.v.i, Czech Academy of Sciences , Prague , Czech Republic
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7
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Functional roles of calreticulin in cancer biology. BIOMED RESEARCH INTERNATIONAL 2015; 2015:526524. [PMID: 25918716 PMCID: PMC4396016 DOI: 10.1155/2015/526524] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/04/2015] [Accepted: 03/05/2015] [Indexed: 11/17/2022]
Abstract
Calreticulin is a highly conserved endoplasmic reticulum chaperone protein which participates in various cellular processes. It was first identified as a Ca2+-binding protein in 1974. Accumulated evidences indicate that calreticulin has great impacts for the development of different cancers and the effect of calreticulin on tumor formation and progression may depend on cell types and clinical stages. Cell surface calreticulin is considered as an “eat-me” signal and promotes phagocytic uptake of cancer cells by immune system. Moreover, several reports reveal that manipulation of calreticulin levels profoundly affects cancer cell proliferation and angiogenesis as well as differentiation. In addition to immunogenicity and tumorigenesis, interactions between calreticulin and integrins have been described during cell adhesion, which is an essential process for cancer metastasis. Integrins are heterodimeric transmembrane receptors which connect extracellular matrix and intracellular cytoskeleton and trigger inside-out or outside-in signaling transduction. More and more evidences reveal that proteins binding to integrins might affect integrin-cytoskeleton interaction and therefore influence ability of cell adhesion. Here, we reviewed the biological roles of calreticulin and summarized the potential mechanisms of calreticulin in regulating mRNA stability and therefore contributed to cancer metastasis.
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Ishii K, Hamamoto H, Sekimizu K. Paralytic peptide: an insect cytokine that mediates innate immunity. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2015; 88:18-30. [PMID: 25521626 DOI: 10.1002/arch.21215] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Host animals combat invading pathogens by activating various immune responses. Modulation of the immune pathways by cytokines is critical for efficient pathogen elimination. Insects and mammals possess common innate immune systems, and individual immune pathways have been intensively studied over the last two decades. Relatively less attention, however, has been focused on the functions of cytokines in insect innate immunity. Here, we summarize our recent findings from studies of the insect cytokine, paralytic peptide, in the silkworm Bombyx mori. The content of this report was presented at the First Asian Invertebrate Immunity Symposium. Acute activation of paralytic peptide occurs via proteolysis after stimulation with the cell wall components of pathogens, leading to the induction of a wide range of cellular and humoral immune responses. The pathogenic bacterium Serratia marcescens suppresses paralytic peptide-dependent immune activation, which impairs host resistance. Studies of insect cytokines will broaden our understanding of the basic mechanisms underlying the interaction between host innate immunity and pathogenic agents.
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Affiliation(s)
- Kenichi Ishii
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
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Dar MA, Wahiduzzaman, Islam A, Hassan MI, Ahmad F. Purification and characterization of calreticulin: a Ca²⁺-binding chaperone from sheep kidney. Appl Biochem Biotechnol 2014; 174:1771-83. [PMID: 25149453 DOI: 10.1007/s12010-014-1150-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/14/2014] [Indexed: 01/02/2023]
Abstract
Calreticulin (CRT) is a molecular chaperone with a molecular mass of 46 kDa present in the endoplasmic reticulum (ER). This protein is primarily involved in the regulation of intracellular Ca(2+) homeostasis and Ca(2+) storage in the ER. CRT also plays a significant role in autoimmunity and cancer. This protein contains three distinct structural domains with specialized functions. Here, we are reporting a simple procedure for the purification of CRT from mammalian kidney. To isolate CRT, sheep kidney was crushed and kept for 12 h in the extraction buffer. The lysate was centrifuged, and supernatant was precipitated by ammonium sulphate. The precipitate of 90 % ammonium sulphate was extensively dialyzed and loaded on DEAE-Hi-Trap FF and Mono Q chromatography columns. The purity of CRT was confirmed by SDS-PAGE. Finally, the protein was identified by matrix-assisted laser desorption/ionization time of flight. The purified protein was further characterized for secondary structural elements using the far-UV circular dichroism measurements. Our purification procedure is fast and simple with high yield.
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Affiliation(s)
- Mohammad Aasif Dar
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, 110025, India
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Kuang XL, Liu F, Chen H, Li Y, Liu Y, Xiao J, Shan G, Li M, Snider BJ, Qu J, Barger SW, Wu S. Reductions of the components of the calreticulin/calnexin quality-control system by proteasome inhibitors and their relevance in a rodent model of Parkinson's disease. J Neurosci Res 2014; 92:1319-29. [PMID: 24860980 DOI: 10.1002/jnr.23413] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 04/16/2014] [Accepted: 04/19/2014] [Indexed: 12/14/2022]
Abstract
Evidence indicates that the ubiquitin-proteasome system and the endoplasmic retculum (ER) quality-control system work in concert to ensure that proteins are correctly folded in the ER and that misfolded proteins are retrotransported to the cytosol for degradation by proteasomes. Dysfunction of either system results in developmental abnormalities and even death in animals. This study investigates whether and how proteasome inhibition impacts the components of the calreticulin (CRT)/calnexin (CNX) glycoprotein folding machinery, a typical ER protein quality-control system, in the context of early neuronal injury. Here we report that proteasome inhibitor treatments, at nonlethal levels, reduced protein levels of CRT and ERp57 but not of CNX. These treatments increased protein levels of CRT in culture media, an effect blocked by brefeldin A, an inhibitor of protein trafficking; by contrast, ERp57 was not detected in culture media. Knockdown of CRT levels alone increased the vulnerability of SH-SY5Y, a neuronal cell line, to 6-hydroxydopamine (6-OHDA) toxicity. In a rat model of Parkinson's disease, intrastriatal 6-OHDA lesions resulted in decreased levels of CRT and ERp57 in the midbrain. These findings suggest that reduction of the components of CRT/CNX glycoprotein quality-control system may play a role in neuronal injury in Parkinson's disease and other neurodegenerative disorders associated with dysfunction of the ubiquitin-proteasome system.
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Affiliation(s)
- Xiu-Li Kuang
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, People's Republic of China
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11
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Czarnowski A, Papp S, Szaraz P, Opas M. Calreticulin affects cell adhesiveness through differential phosphorylation of insulin receptor substrate-1. Cell Mol Biol Lett 2014; 19:77-97. [PMID: 24470116 PMCID: PMC6275655 DOI: 10.2478/s11658-014-0181-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 01/20/2014] [Indexed: 11/21/2022] Open
Abstract
Cellular adhesion to the underlying substratum is regulated through numerous signaling pathways. It has been suggested that insulin receptor substrate 1 (IRS-1) is involved in some of these pathways, via association with and activation of transmembrane integrins. Calreticulin, as an important endoplasmic reticulum-resident, calcium-binding protein with a chaperone function, plays an obvious role in proteomic expression. Our previous work showed that calreticulin mediates cell adhesion not only by affecting protein expression but also by affecting the state of regulatory protein phosphorylation, such as that of c-src. Here, we demonstrate that calreticulin affects the abundance of IRS-1 such that the absence of calreticulin is paralleled by a decrease in IRS-1 levels and the unregulated overexpression of calreticulin is accompanied by an increase in IRS-1 levels. These changes in the abundance of calreticulin and IRS-1 are accompanied by changes in cell-substratum adhesiveness and phosphorylation, such that increases in the expression of calreticulin and IRS-1 are paralleled by an increase in focal contact-based cell-substratum adhesiveness, and a decrease in the expression of these proteins brings about a decrease in cell-substratum adhesiveness. Wild type and calreticulin-null mouse embryonic fibroblasts (MEFs) were cultured and the IRS-1 isoform profile was assessed. Differences in morphology and motility were also quantified. While no substantial differences in the speed of locomotion were found, the directionality of cell movement was greatly promoted by the presence of calreticulin. Calreticulin expression was also found to have a dramatic effect on the phosphorylation state of serine 636 of IRS-1, such that phosphorylation of IRS-1 on serine 636 increased radically in the absence of calreticulin. Most importantly, treatment of cells with the RhoA/ROCK inhibitor, Y-27632, which among its many effects also inhibited serine 636 phosphorylation of IRS-1, had profound effects on cell-substratum adhesion, in that it suppressed focal contacts, induced extensive close contacts, and increased the strength of adhesion. The latter effect, while counterintuitive, can be explained by the close contacts comprising labile bonds but in large numbers. In addition, the lability of bonds in close contacts would permit fast locomotion. An interesting and novel finding is that Y-27632 treatment of MEFs releases them from contact inhibition of locomotion, as evidenced by the invasion of a cell's underside by the thin lamellae and filopodia of a cell in close apposition.
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Affiliation(s)
- Arthur Czarnowski
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario Canada M5S 1A8
| | - Sylvia Papp
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario Canada M5S 1A8
| | - Peter Szaraz
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario Canada M5S 1A8
| | - Michal Opas
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario Canada M5S 1A8
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King’s College Circle, Medical Sciences Building, room 6326, Toronto, Ontario M5S 1A8 Canada
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Disrupted WNT Signaling in Mouse Embryonic Stem Cells in the Absence of Calreticulin. Stem Cell Rev Rep 2014; 10:191-206. [DOI: 10.1007/s12015-013-9488-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Ishii K, Adachi T, Hamamoto H, Sekimizu K. Serratia marcescens suppresses host cellular immunity via the production of an adhesion-inhibitory factor against immunosurveillance cells. J Biol Chem 2014; 289:5876-88. [PMID: 24398686 DOI: 10.1074/jbc.m113.544536] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Injection of a culture supernatant of Serratia marcescens into the bloodstream of the silkworm Bombyx mori increased the number of freely circulating immunosurveillance cells (hemocytes). Using a bioassay with live silkworms, serralysin metalloprotease was purified from the culture supernatant and identified as the factor responsible for this activity. Serralysin inhibited the in vitro attachment of both silkworm hemocytes and murine peritoneal macrophages. Incubation of silkworm hemocytes or murine macrophages with serralysin resulted in degradation of the cellular immune factor BmSPH-1 or calreticulin, respectively. Furthermore, serralysin suppressed in vitro phagocytosis of bacteria by hemocytes and in vivo bacterial clearance in silkworms. Disruption of the ser gene in S. marcescens attenuated its host killing ability in silkworms and mice. These findings suggest that serralysin metalloprotease secreted by S. marcescens suppresses cellular immunity by decreasing the adhesive properties of immunosurveillance cells, thereby contributing to bacterial pathogenesis.
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Affiliation(s)
- Kenichi Ishii
- From the Laboratory of Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033, Japan
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14
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Knight DK, Stutchbury R, Imruck D, Halfpap C, Lin S, Langbein U, Gillies ER, Mittler S, Mequanint K. Focal contact formation of vascular smooth muscle cells on Langmuir-Blodgett and solvent-cast films of biodegradable poly(ester amide)s. ACS APPLIED MATERIALS & INTERFACES 2012; 4:1303-1312. [PMID: 22324781 DOI: 10.1021/am201582q] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The ability of biomaterials to support the adhesion of cells is a necessary condition for their use in scaffold-guided tissue engineering. Waveguide evanescent field fluorescence (WEFF) microscopy is a relatively new microscopic technique that allows the number of cell adhesions to a waveguide surface be measured by imaging the interfacial contact region between the cells and their substratum. In this work, the adhesion of human coronary artery smooth muscle cells (HCASMCs) to ultrathin films (20 nm) of poly(ester amide)s (PEAs) prepared by Langmuir-Blodgett (LB) technology on waveguides was investigated and compared with conventional vinculin immunostaining on solvent cast PEA films. Cell culture was conducted both in the presence and absence of serum to evaluate the effect of nonspecific protein adsorption that mediates cell adhesion. WEFF microscopy analyses revealed that the cationic PEA enhanced the number of attachment sites compared with the control waveguides regardless of the culture medium. Although differences in cell adhesions between different PEAs were suggested by the results, no statistically significant differences were found. Similar results were observed with presently and previously reported vinculin immunostaining studies, further validating the use of WEFF microscopy to quantify cell adhesions. Moreover, the focal adhesions of the HCASMCs to the PEA surfaces indicate these PEAs can promote integrin signaling, which is vital in cell survival, migration, and proliferation, and ultimately in scaffold-guided vascular tissue engineering.
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Affiliation(s)
- Darryl K Knight
- Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, Ontario, Canada
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15
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Papp S, Fadel MP, Opas M. Dissecting focal adhesions in cells differentially expressing calreticulin: a microscopy study. Biol Cell 2012; 99:389-402. [PMID: 17373910 DOI: 10.1042/bc20060105] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND INFORMATION Our previous studies have shown that calreticulin, a Ca2+-binding chaperone located in the endoplasmic reticulum, affects cell-substratum adhesions via the induction of vinculin and N-cadherin. Cells overexpressing calreticulin contain more vinculin than low expressers and make abundant contacts with the substratum. However, cells that express low levels of calreticulin exhibit a weak adhesive phenotype and make few, if any, focal adhesions. To date, the identity of the types of focal adhesions made by calreticulin overexpressing and low expressing cells has not been dissected. RESULTS The results of the present study show that calreticulin affects fibronectin matrix assembly in L fibroblast cell lines that differentially express the protein, and that these cells also differ profoundly in focal adhesion formation. Although the calreticulin overexpressing cells generate numerous interference-reflection-microscopy-dark, vinculin- and paxillin-containing classical focal contacts, as well as some fibrillar adhesions, the cells expressing low levels of calreticulin generate only a few weak focal adhesions. The fibronectin receptor was found to be clustered in calreticulin overexpressing cells, but diffusely distributed over the cell surface in low expressing cells. Plating L fibroblasts on fibronectin-coated substrata induced extensive spreading in all cell lines tested. However, although calreticulin overexpressing cells were induced to form classical vinculin-rich focal contacts, the low calreticulin expressing cells overcame their weak adhesive phenotype by induction of many tensin-rich fibrillar adhesions, thus compensating for the low level of vinculin in these cells. CONCLUSIONS We propose that calreticulin affects fibronectin production and, thereby, assembly, and it indirectly influences the formation and/or stability of focal contacts and fibrillar adhesions, both of which are instrumental in matrix assembly and remodelling.
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Affiliation(s)
- Sylvia Papp
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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16
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Lu YC, Chen CN, Wang B, Hsu WM, Chen ST, Chang KJ, Chang CC, Lee H. Changes in tumor growth and metastatic capacities of J82 human bladder cancer cells suppressed by down-regulation of calreticulin expression. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:1425-33. [PMID: 21723245 DOI: 10.1016/j.ajpath.2011.05.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 04/20/2011] [Accepted: 05/12/2011] [Indexed: 10/18/2022]
Abstract
Bladder cancer is a common urothelial cancer. Through proteomic approaches, calreticulin (CRT) was identified and proposed as a urinary marker for bladder cancer. CRT is a multifunctional molecular chaperone that regulates various cellular functions such as Ca(2+) homeostasis and cell adhesion. CRT is overexpressed in various cancers, but its mechanism of action in the development of bladder tumors remains unclear. We generated J82 bladder cancer cells lines that either stably overexpressed or knocked down CRT to investigate the physiological effects of CRT on bladder tumors. Compared with the transfected control vector cells, the knockdown of CRT suppressed cell proliferation, migration, and attachment, whereas overexpression of CRT enhanced cell migration and attachment. We further demonstrated that the phosphorylation status of focal adhesion kinase and paxillin, important regulators of the focal adhesion complex, was also regulated in these cells. In contrast, phosphorylation of Src, a protein tyrosine kinase reported to be affected by CRT, was not significantly different between the control and CRT-RNAi groups. Most importantly, we observed that tumors derived from J82 CRT-RNAi cells were significantly smaller and had fewer metastatic sites in the lung and liver in vivo than did transfected control vector cells. In conclusion, our results suggest that alteration of CRT expression levels might affect bladder cancer progression in vitro and in vivo.
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Affiliation(s)
- Yi-Chien Lu
- Institute of Zoology, National Taiwan University, Taipei, Taiwan
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17
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Abstract
Ca2+ is a universal signalling molecule that affects a variety of cellular processes including cardiac development. The majority of intracellular Ca2+ is stored in the endoplasmic and sarcoplasmic reticulum of muscle and non-muscle cells. Calreticulin is a well studied Ca2+-buffering protein in the endoplasmic reticulum, and calreticulin deficiency is embryonic lethal due to impaired cardiac development. Despite calsequestrin being the most abundant Ca2+-buffering protein in the sarcoplasmic reticulum, viability is maintained in embryos without calsequestrin and normal Ca2+ release and contractile function is observed. The Ca2+ homeostasis regulated by the endoplasmic and sarcoplasmic reticulum is critical for the development and proper function of the heart.
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Affiliation(s)
- Dukgyu Lee
- Department of Biochemistry, School of Molecular and Systems Medicine, University of Alberta, Edmonton, Alberta, Canada T6G2H7
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18
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Van Duyn Graham L, Sweetwyne MT, Pallero MA, Murphy-Ullrich JE. Intracellular calreticulin regulates multiple steps in fibrillar collagen expression, trafficking, and processing into the extracellular matrix. J Biol Chem 2010; 285:7067-78. [PMID: 20044481 PMCID: PMC2844156 DOI: 10.1074/jbc.m109.006841] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 12/29/2009] [Indexed: 12/19/2022] Open
Abstract
Calreticulin (CRT), a chaperone and Ca(2+) regulator, enhances wound healing, and its expression correlates with fibrosis in animal models, suggesting that CRT regulates production of the extracellular matrix. However, direct regulation of collagen matrix by CRT has not been previously demonstrated. We investigated the role of CRT in the regulation of fibrillar collagen expression, secretion, processing, and deposition in the extracellular matrix by fibroblasts. Mouse embryonic fibroblasts deficient in CRT (CRT(-/-) MEFs) have reduced transcript levels of fibrillar collagen I and III and less soluble collagen as compared with wild type MEFs. Correspondingly, fibroblasts engineered to overexpress CRT have increased collagen type I transcript and protein. Collagen expression appears to be regulated by endoplasmic reticulum (ER) calcium levels and intracellular CRT, because thapsigargin treatment reduced collagen expression, whereas addition of exogenous recombinant CRT had no effect. CRT(-/-) MEFs exhibited increased ER retention of collagen, and collagen and CRT were co-immunoprecipitated from isolated cell lysates, suggesting that CRT is important for trafficking of collagen through the ER. CRT(-/-) MEFs also have reduced type I procollagen processing and deposition into the extracellular matrix. The reduced collagen matrix deposition is partly a consequence of reduced fibronectin matrix formation in the CRT-deficient cells. Together, these data show that CRT complexes with collagen in cells and that CRT plays critical roles at multiple stages of collagen expression and processing. These data identify CRT as an important regulator of collagen and suggest that intracellular CRT signaling plays an important role in tissue remodeling and fibrosis.
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Affiliation(s)
| | - Mariya T. Sweetwyne
- Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
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19
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Szabo E, Feng T, Dziak E, Opas M. Cell adhesion and spreading affect adipogenesis from embryonic stem cells: the role of calreticulin. Stem Cells 2009; 27:2092-102. [PMID: 19544411 DOI: 10.1002/stem.137] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Calreticulin is an endoplasmic reticulum-resident multifunctional protein, which has been shown to influence numerous cellular processes, including cell adhesion. In this study, we characterized the adhesive properties of embryonic stem cells (ESCs) lacking calreticulin and showed that adipogenesis from ESCs is directly and reciprocally controlled by the adhesive status of a cell, which in turn is modulated by calreticulin. Calreticulin-deficient ESCs are not only highly adipogenic but also show elevated calmodulin/CaMKII signaling and poor adhesiveness compared with the wild-type ESCs. Calreticulin deficiency leads to a disorganized cytoskeleton and low levels of focal adhesion-related proteins, such as vinculin, paxillin, and phosphorylated focal adhesion kinase, which cause limited focal adhesion formation and limited fibronectin deposition. Moreover, differentiation on nonadhesive substrata, which hinder cell spreading, promoted adipogenesis in the wild-type ESCs that normally have low adipogenic potential, causing a decrease in focal adhesion protein expression and an increase in calmodulin/CaMKII signaling. In contrast, inhibition of CaMKII effectively increased focal adhesion protein levels and inhibited adipogenesis in calreticulin-deficient ESCs, causing them to behave like the low adipogenic, wild-type ESCs. Thus, the adipogenic potential of ESCs is proportional to their calmodulin/CaMKII activity but is inversely related to their focal adhesion protein levels and degree of adhesiveness/spreading.
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Affiliation(s)
- Eva Szabo
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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20
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Villagomez M, Szabo E, Podcheko A, Feng T, Papp S, Opas M. Calreticulin and focal-contact-dependent adhesion. Biochem Cell Biol 2009; 87:545-56. [PMID: 19767819 DOI: 10.1139/o09-016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cell adhesion is regulated by a variety of Ca2+-regulated pathways that depend on Ca2+-binding proteins. One such protein is calreticulin, an ER-resident protein. Calreticulin signalling from within the ER can affect processes outside the ER, such as expression of several adhesion-related genes, most notably vinculin and fibronectin. In addition, changes in the expression level of calreticulin strongly affect tyrosine phosphorylation of cellular proteins, which is known to affect many adhesion-related functions. While calreticulin has been localized to cellular compartments other than the ER, it appears that only the ER-resident calreticulin affects focal-contact-dependent adhesion. In contrast, calreticulin residing outside the ER may be involved in contact disassembly and other adhesion phenomena. Here, we review the role of calreticulin in focal contact initiation, stabilization, and turnover. We propose that calreticulin may regulate cell-substratum adhesion by participating in an "ER-to-nucleus" signalling and in parallel "ER-to-cell surface" signalling based on posttranslational events.
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Affiliation(s)
- Maria Villagomez
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King's College Circle, Medical Sciences Building, Toronto, ON M5S 1A8, Canada
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21
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Alur M, Nguyen MM, Eggener SE, Jiang F, Dadras SS, Stern J, Kimm S, Roehl K, Kozlowski J, Pins M, Michalak M, Dhir R, Wang Z. Suppressive roles of calreticulin in prostate cancer growth and metastasis. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 175:882-90. [PMID: 19608864 DOI: 10.2353/ajpath.2009.080417] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Calreticulin is an essential, multifunctional Ca(2+)-binding protein that participates in the regulation of intracellular Ca(2+) homeostasis, cell adhesion, and chaperoning. Calreticulin is abundantly expressed and regulated by androgens in prostate epithelial cells. Given the importance of both calreticulin in multiple essential cellular activities and androgens in prostate cancer, we investigated the possibility of a role for calreticulin in prostate cancer progression. Immunohistochemistry revealed the down-regulation of calreticulin in a subset of human prostate cancer specimens. Prostate cancer cells overexpressing exogenous calreticulin produced fewer colonies in both monolayer culture and soft agar. Furthermore, calreticulin overexpression also inhibited tumor growth in the orthotopic PC3 xenograft tumor model and macroscopic lung metastasis in the rat Dunning AT3.1 prostate tumor model. To address the potential mechanism of calreticulin suppression of prostate cancer, we generated calreticulin mutants with different functional domains deleted. The calreticulin mutants containing the P-domain, which binds to other endoplasmic reticulum chaperone proteins, were sufficient for the suppression of PC3 growth in colony formation assays. Overall, our data support the hypothesis that calreticulin inhibits growth and/or metastasis of prostate cancer cells and that this suppression requires the P-domain.
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Affiliation(s)
- Mahesh Alur
- Department of Urology, University of Pittsburgh, 5200 Centre Ave., Shadyside Medical Center, Suite G40, Pittsburgh, PA 15232, USA
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22
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Michalak M, Groenendyk J, Szabo E, Gold L, Opas M. Calreticulin, a multi-process calcium-buffering chaperone of the endoplasmic reticulum. Biochem J 2009; 417:651-666. [DOI: 10.1042/bj20081847] [Citation(s) in RCA: 528] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Calreticulin is an ER (endoplasmic reticulum) luminal Ca2+-buffering chaperone. The protein is involved in regulation of intracellular Ca2+ homoeostasis and ER Ca2+ capacity. The protein impacts on store-operated Ca2+ influx and influences Ca2+-dependent transcriptional pathways during embryonic development. Calreticulin is also involved in the folding of newly synthesized proteins and glycoproteins and, together with calnexin (an integral ER membrane chaperone similar to calreticulin) and ERp57 [ER protein of 57 kDa; a PDI (protein disulfide-isomerase)-like ER-resident protein], constitutes the ‘calreticulin/calnexin cycle’ that is responsible for folding and quality control of newly synthesized glycoproteins. In recent years, calreticulin has been implicated to play a role in many biological systems, including functions inside and outside the ER, indicating that the protein is a multi-process molecule. Regulation of Ca2+ homoeostasis and ER Ca2+ buffering by calreticulin might be the key to explain its multi-process property.
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Affiliation(s)
- Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2H7
| | - Jody Groenendyk
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2H7
| | - Eva Szabo
- Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada, M5S 1A8
| | - Leslie I. Gold
- Departments of Medicine and Pathology, New York University School of Medicine, New York, NY 10016, U.S.A
| | - Michal Opas
- Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada, M5S 1A8
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23
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Nanney LB, Woodrell CD, Greives MR, Cardwell NL, Pollins AC, Bancroft TA, Chesser A, Michalak M, Rahman M, Siebert JW, Gold LI. Calreticulin enhances porcine wound repair by diverse biological effects. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 173:610-30. [PMID: 18753412 DOI: 10.2353/ajpath.2008.071027] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Extracellular functions of the endoplasmic reticulum chaperone protein calreticulin (CRT) are emerging. Here we show novel roles for exogenous CRT in both cutaneous wound healing and diverse processes associated with repair. Compared with platelet-derived growth factor-BB-treated controls, topical application of CRT to porcine excisional wounds enhanced the rate of wound re-epithelialization. In both normal and steroid-impaired pigs, CRT increased granulation tissue formation. Immunohistochemical analyses of the wounds 5 and 10 days after injury revealed marked up-regulation of transforming growth factor-beta3 (a key regulator of wound healing), a threefold increase in macrophage influx, and an increase in the cellular proliferation of basal keratinocytes of the new epidermis and of cells of the neodermis. In vitro studies confirmed that CRT induced a greater than twofold increase in the cellular proliferation of primary human keratinocytes, fibroblasts, and microvascular endothelial cells (with 100 pg/ml, 100 ng/ml, and 1.0 pg/ml, respectively). Moreover, using a scratch plate assay, CRT maximally induced the cellular migration of keratinocytes and fibroblasts (with 10 pg/ml and 1 ng/ml, respectively). In addition, CRT induced concentration-dependent migration of keratinocytes, fibroblasts macrophages, and monocytes in chamber assays. These in vitro bioactivities provide mechanistic support for the positive biological effects of CRT observed on both the epidermis and dermis of wounds in vivo, underscoring a significant role for CRT in the repair of cutaneous wounds.
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Affiliation(s)
- Lillian B Nanney
- Department of Plastic Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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24
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Szabo E, Qiu Y, Baksh S, Michalak M, Opas M. Calreticulin inhibits commitment to adipocyte differentiation. ACTA ACUST UNITED AC 2008; 182:103-16. [PMID: 18606846 PMCID: PMC2447897 DOI: 10.1083/jcb.200712078] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Calreticulin, an endoplasmic reticulum (ER) resident protein, affects many critical cellular functions, including protein folding and calcium homeostasis. Using embryonic stem cells and 3T3-L1 preadipocytes, we show that calreticulin modulates adipogenesis. We find that calreticulin-deficient cells show increased potency for adipogenesis when compared with wild-type or calreticulin-overexpressing cells. In the highly adipogenic crt−/− cells, the ER lumenal calcium concentration was reduced. Increasing the ER lumenal calcium concentration led to a decrease in adipogenesis. In calreticulin-deficient cells, the calmodulin–Ca2+/calmodulin-dependent protein kinase II (CaMKII) pathway was up-regulated, and inhibition of CaMKII reduced adipogenesis. Calreticulin inhibits adipogenesis via a negative feedback mechanism whereby the expression of calreticulin is initially up-regulated by peroxisome proliferator–activated receptor γ (PPARγ). This abundance of calreticulin subsequently negatively regulates the expression of PPARγ, lipoprotein lipase, CCAAT enhancer–binding protein α, and aP2. Thus, calreticulin appears to function as a Ca2+-dependent molecular switch that regulates commitment to adipocyte differentiation by preventing the expression and transcriptional activation of critical proadipogenic transcription factors.
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Affiliation(s)
- Eva Szabo
- Department of Laboratory Medicine and Pathobiology, Institute of Medical Sciences, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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25
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Papp S, Szabo E, Kim H, McCulloch CA, Opas M. Kinase-dependent adhesion to fibronectin: Regulation by calreticulin. Exp Cell Res 2008; 314:1313-26. [DOI: 10.1016/j.yexcr.2008.01.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 12/11/2007] [Accepted: 01/07/2008] [Indexed: 11/17/2022]
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26
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Zoeller JJ, Iozzo RV. Proteomic profiling of endorepellin angiostatic activity on human endothelial cells. Proteome Sci 2008; 6:7. [PMID: 18269764 PMCID: PMC2275231 DOI: 10.1186/1477-5956-6-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Accepted: 02/12/2008] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Endorepellin, the C-terminal domain V of the heparan sulfate proteoglycan perlecan, exhibits powerful and targeted anti-angiogenic activity on endothelial cells. To identify proteins involved with endorepellin anti-angiogenic action, we performed an extensive comparative proteomic analysis between vehicle- and endorepellin-treated human endothelial cells. RESULTS Proteomic analysis of endorepellin influence on human umbilical vein endothelial cells identified five differentially expressed proteins, three of which (beta-actin, calreticulin, and chaperonin/Hsp60) were down-regulated and two of which (vimentin and the beta subunit of prolyl 4-hydroxylase also known as protein disulfide isomerase) were up-regulated in response to endorepellin treatment-and associated with a fold change (endorepellin/control) = 0.75 and >/= 2.00, and a statistically significant p-value as determined by Student's t test. CONCLUSION The proteins identified represent potential target areas involved with endorepellin anti-angiogenic mechanism of action. Further elucidation as such will ultimately provide useful in utilizing endorepellin as an anti-angiogenic therapy in humans.
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Affiliation(s)
- Jason J Zoeller
- Department of Pathology, Anatomy and Cell Biology, and the Cancer Cell Biology and Signalling Program, Kimmel Cancer Center, 1020 Locust Street, Room 249 JAH, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Renato V Iozzo
- Department of Pathology, Anatomy and Cell Biology, and the Cancer Cell Biology and Signalling Program, Kimmel Cancer Center, 1020 Locust Street, Room 249 JAH, Thomas Jefferson University, Philadelphia, PA, 19107, USA
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27
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Szabo E, Papp S, Opas M. Differential calreticulin expression affects focal contacts via the calmodulin/CaMK II pathway. J Cell Physiol 2007; 213:269-77. [PMID: 17516550 DOI: 10.1002/jcp.21122] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Calreticulin is an ER calcium-storage protein, which influences gene expression and cell adhesion. In this study, we analysed the differences in adhesive properties of calreticulin under- and overexpressing fibroblasts in relation to the calmodulin- and calcium/calmodulin-dependent kinase II (CaMK II)-dependent signalling pathways. Cells stably underexpressing calreticulin had elevated expression of calmodulin, activated CaMK II, activated ERK and activated c-src. Inhibition of calmodulin by W7, and CaMK II by KN-62, caused the otherwise weekly adhesive calreticulin underexpressing cells to behave like the overexpressing cells, via induction of increased cell spreading. Increased vinculin, activated paxillin, activated focal adhesion kinase and fibronectin levels were observed upon inhibition of either the calmodulin or the CaMK II signalling pathways, which was accompanied by an increase in cell spreading and focal contact formation. Both KN-62 and W7 treatment increased cell motility in underexpressing cells, but W7 treatment led to loss of directionality. Thus, both the calmodulin and CaMK II signalling pathways influence cellular spreading and motility, but subtle differences exist in their distal effects on motility effectors.
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Affiliation(s)
- Eva Szabo
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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28
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Papp S, Fadel MP, Michalak M, Opas M. Analysis of the suitability of calreticulin inducible HEK cells for adhesion studies: microscopical and biochemical comparisons. Mol Cell Biochem 2007; 307:237-48. [PMID: 17909946 DOI: 10.1007/s11010-007-9602-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Accepted: 08/27/2007] [Indexed: 01/10/2023]
Abstract
Calreticulin is a Ca(2+)-buffering ER chaperone that also modulates cell adhesiveness. In order to study the effect of calreticulin on the expression of adhesion-related genes, we created a calreticulin inducible Human Embryonic Kidney (HEK) 293 cell line. We found that fibronectin mRNA and both intra- and extra-cellular fibronectin protein levels increased following calreticulin induction. However, despite this increase in fibronectin, HEK293 cells did not assemble an extracellular fibrillar fibronectin matrix regardless of the level of calreticulin expression. Furthermore, HEK293 cells exhibited a poorly organized actin cytoskeleton, did not have clustered fibronectin receptors at the cell surface, and did not form focal contacts. This likely accounts for the lack of fibronectin matrix deposition by these cells regardless of calreticulin expression level. Vinculin abundance did not appreciably increase upon calreticulin induction and the level of active c-Src, a regulatory kinase of focal contacts, was found to be abundant and unregulated by calreticulin induction in these cells. The inability to form stable focal contacts and to commence fibronectin fibrillogenesis due to high c-Src activity may be responsible for the poor adhesive phenotype of HEK 293 cells. Thus, we show here that HEK293 cells are not suitable for microscopical studies of cell-substratum adhesions, but are best suited for biochemical studies.
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Affiliation(s)
- Sylvia Papp
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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29
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Papp S, Fadel MP, Kim H, McCulloch CA, Opas M. Calreticulin affects fibronectin-based cell-substratum adhesion via the regulation of c-Src activity. J Biol Chem 2007; 282:16585-98. [PMID: 17389592 DOI: 10.1074/jbc.m701011200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Calreticulin is an endoplasmic reticulum Ca2+-storage protein, which influences gene expression and cell adhesion. In this study, we show that calreticulin induces fibronectin gene expression and matrix deposition, leading to differences in cell spreading and focal adhesion formation in cells differentially expressing calreticulin. We further show that these effects of calreticulin occur via a c-Src-regulated pathway and that c-Src activity is inversely related to calreticulin abundance. Since c-Src is an important regulator of focal contact turnover, we investigated the effect of c-Src inhibition on cells differentially expressing calreticulin. Inhibition of c-Src rescued the poorly adhesive phenotype of the calreticulin-underexpressing cells in that they became well spread, commenced formation of numerous focal contacts, and deposited a rich fibronectin matrix. Importantly, we show that c-Src activity is dependent on releasable Ca2+ from the endoplasmic reticulum, thus implicating Ca2+-sensitive pathways that are affected by calreticulin in cell-substratum adhesion. We propose that calreticulin affects fibronectin synthesis and matrix assembly via the regulation of fibronectin gene expression. In parallel, calcium-dependent effects of calreticulin on c-Src activity influence the formation and/or stability of focal contacts, which are instrumental in matrix assembly and remodeling.
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Affiliation(s)
- Sylvia Papp
- Department of Laboratory Medicine and Pathobiology and Canadian Institutes of Health Research Group in Matrix Dynamics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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Opas M, Fadel MP. Partial reversal of transformed fusiform phenotype by overexpression of calreticulin. Cell Mol Biol Lett 2006; 12:294-307. [PMID: 17149557 PMCID: PMC6275922 DOI: 10.2478/s11658-006-0065-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Accepted: 11/20/2006] [Indexed: 11/20/2022] Open
Abstract
Calreticulin, a Ca2+-storage and chaperone protein of the ER, has also been shown to affect cell adhesiveness. To examine the effects of differential expression of calreticulin on cellular adhesiveness, we used L fibroblast cell lines stably expressing either elevated or reduced amounts of full length, ER-targeted calreticulin. Overexpression of calreticulin correlates with an increase in adhesiveness of L fibroblasts such that these transformed cells acquire epithelioid morphology and form an epithelial-cell sheet when crowded. Functionally, the “reversal” of transformed phenotype in L fibroblasts differentially overexpressing calreticulin can be accounted for by changes in levels of expression of N-cadherin and vinculin. Structurally, however, although the form and extent of cell-cell contacts in L fibroblasts overexpressing calreticulin mimicked those in normal epithelia, electron microscopical examination revealed that cell-cell junctions formed by these transformed cells bore only superficial resemblance to those of normal epithelia in culture. Our data imply that overexpression of calreticulin, while partially reverses fusiform transformed phenotype is in itself insufficient to re-establish bona fide zonulae adherens in transformed fibroblasts.
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Affiliation(s)
- Michal Opas
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
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31
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Ultrastructural analysis of development of myocardium in calreticulin-deficient mice. BMC DEVELOPMENTAL BIOLOGY 2006; 6:54. [PMID: 17112388 PMCID: PMC1660575 DOI: 10.1186/1471-213x-6-54] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Accepted: 11/19/2006] [Indexed: 01/24/2023]
Abstract
BACKGROUND Calreticulin is a Ca2+ binding chaperone of the endoplasmic reticulum which influences gene expression and cell adhesion. The levels of both vinculin and N-cadherin are induced by calreticulin expression, which play important roles in cell adhesiveness. Cardiac development is strictly dependent upon the ability of cells to adhere to their substratum and to communicate with their neighbours. RESULTS We show here that the levels of N-cadherin are downregulated in calreticulin-deficient mouse embryonic hearts, which may lead to the disarray and wavy appearance of myofibrils in these mice, which we detected at all investigated stages of cardiac development. Calreticulin wild type mice exhibited straight, thick and abundant myofibrils, which were in stark contrast to the thin, less numerous, disorganized myofibrils of the calreticulin-deficient hearts. Interestingly, these major differences were only detected in the developing ventricles while the atria of both calreticulin phenotypes were similar in appearance at all developmental stages. Glycogen also accumulated in the ventricles of calreticulin-deficient mice, indicating an abnormality in cardiomyocyte metabolism. CONCLUSION Calreticulin is temporarily expressed during heart development where it is required for proper myofibrillogenesis. We postulate that calreticulin be considered as a novel cardiac fetal gene.
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Gold LI, Rahman M, Blechman KM, Greives MR, Churgin S, Michaels J, Callaghan MJ, Cardwell NL, Pollins AC, Michalak M, Siebert JW, Levine JP, Gurtner GC, Nanney LB, Galiano RD, Cadacio CL. Overview of the role for calreticulin in the enhancement of wound healing through multiple biological effects. J Investig Dermatol Symp Proc 2006; 11:57-65. [PMID: 17069011 DOI: 10.1038/sj.jidsymp.5650011] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Calreticulin (CRT), an intracellular chaperone protein crucial for the proper folding and transport of proteins through the endoplasmic reticulum, has more recent acclaim as a critical regulator of extracellular functions, particularly in mediating cellular migration and as a requirement for phagocytosis of apoptotic cells. Consistent with these functions, we show that the topical application of CRT has profound effects on the process of wound healing by causing a dose-dependent increase in epithelial migration and granulation tissue formation in both murine and porcine normal and impaired animal models of skin injury. These effects of CRTare substantiated, in vitro, as we show that CRT strongly induces cell migration/wound closure of human keratinocytes and fibroblasts, using a wound/scratch plate assay, and stimulates cellular proliferation of human keratinocytes, fibroblasts, and vascular endothelial cells, providing mechanistic insight into how CRT functions in repair. Similarly, in both animal models, the histology of the wounds show marked proliferation of basal keratinocytes and dermal fibroblasts, dense cellularity of the dermis with notably increased numbers of macrophages and well-organized collagen fibril deposition. Thus, CRT profoundly affects the wound healing process by recruiting cells essential for repair into the wound, stimulating cell growth, and increasing extracellular matrix production.
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Affiliation(s)
- Leslie I Gold
- Department of Medicine, New York University School of Medicine, New York, New York 10016, USA.
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Franco C, Ho B, Mulholland D, Hou G, Islam M, Donaldson K, Bendeck MP. Doxycycline alters vascular smooth muscle cell adhesion, migration, and reorganization of fibrillar collagen matrices. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:1697-709. [PMID: 16651635 PMCID: PMC1606579 DOI: 10.2353/ajpath.2006.050613] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Remodeling of injured blood vessels is dependent on smooth muscle cells and matrix metalloproteinase activity. Doxycycline is a broad spectrum matrix metalloproteinase inhibitor that is under investigation for the treatment of acute coronary syndromes and aneurysms. In the present study, we examine the mechanisms by which doxycycline inhibits smooth muscle cell responses using a series of in vitro assays that mimic critical steps in pathological vascular remodeling. Doxycycline treatment dramatically increased smooth muscle cell adhesion to the substrate, as evidenced by interference reflection microscopy and immunostaining for paxillin and phosphotyrosine. Cell aggregation was also potentiated after treatment with doxycycline. Treatment with 104 mumol/L doxycycline reduced thymidine uptake by 58% compared with untreated cells (P < 0.05) and inhibited closure of a scrape wound made in a smooth muscle cell monolayer by 20% (P < 0.05). Contraction of a three-dimensional collagen gel was used as an in vitro model for constrictive vessel remodeling, demonstrating that treatment with 416 mumol/L doxycycline for 12 hours inhibited collagen gel remodeling by 37% relative to control (P < 0.05). In conclusion, we have shown that doxycycline treatment leads to dramatically increased smooth muscle cell adhesion, which in turn might limit responses in pathological vascular remodeling.
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Affiliation(s)
- Christopher Franco
- Department of Laboratory Medicine and Pathobiology, University of Toronto, ON, Canada M5S 1A8
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34
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Li SS, Liu Z, Uzunel M, Sundqvist KG. Endogenous thrombospondin-1 is a cell-surface ligand for regulation of integrin-dependent T-lymphocyte adhesion. Blood 2006; 108:3112-20. [PMID: 16835379 DOI: 10.1182/blood-2006-04-016832] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Lymphocyte adhesion to cells and extracellular matrix (ECM) via integrins plays a pivotal role for the function of the immune system. We show here that endogenous thrombospondin-1 (TSP-1) is a cell-surface ligand for cis interaction of surface receptors in T lymphocytes controlled by integrins and the T-cell antigen receptor (TCR/CD3). Stimulation of CD3 triggers rapid surface expression of TSP-1 in quiescent T cells, whereas activated cells express TSP-1 constitutively. Endogenous TSP-1 is attached to lipoprotein receptor-related protein 1 (LRP1/CD91) and calreticulin (CRT) on the cell surface through its NH2-terminal domain. Adhesion via integrins to ICAM-1 or ECM components up-regulates TSP turnover dramatically from a low level in nonadherent cells, whereas CD3 stimulation inhibits TSP turnover through interference with CD91/CRT-mediated internalization. Integrin-associated protein (IAP/CD47) is essential for TSP turnover and adhesion through interaction with the C-terminal domain of TSP-1 in response to triggering signals delivered at the NH2-terminal. These results indicate that endogenous TSP-1 connects separate cell-surface receptors functionally and regulates T-cell adhesion.
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Affiliation(s)
- Shu Shun Li
- Department of Laboratory Medicine, Division of Clinical Immunology, Karolinska Institute at Karolinska University Hospital Huddinge, Stockholm, Sweden
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35
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Williams DB. Beyond lectins: the calnexin/calreticulin chaperone system of the endoplasmic reticulum. J Cell Sci 2006; 119:615-23. [PMID: 16467570 DOI: 10.1242/jcs.02856] [Citation(s) in RCA: 341] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Calnexin and calreticulin are related proteins that comprise an ER chaperone system that ensures the proper folding and quality control of newly synthesized glycoproteins. The specificity for glycoproteins is conferred by a lectin site that recognizes an early oligosaccharide processing intermediate on the folding glycoprotein, Glc1Man9GlcNAc2. In addition, calnexin and calreticulin possess binding sites for ATP, Ca2+, non-native polypeptides and ERp57, an enzyme that catalyzes disulfide bond formation, reduction and isomerization. Recent studies have revealed the locations of some of these ligand-binding sites and have provided insights into how they contribute to overall chaperone function. In particular, the once controversial non-native-polypeptide-binding site has now been shown to function both in vitro and in cells. Furthermore, there is clear evidence that ERp57 participates in glycoprotein biogenesis either alone or in tandem with calnexin and calreticulin.
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Affiliation(s)
- David B Williams
- Department of Biochemistry and Immunology, University of Toronto, Toronto, Ontario, Canada, M5S 1A8.
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36
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Szabo E, Papp S, Opas M. Calreticulin and cellular adhesion/migration-specific signalling pathways. J Appl Biomed 2006. [DOI: 10.32725/jab.2006.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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37
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Michalak M. Endoplasmic reticulum quality control and congenital pathology. J Appl Biomed 2005. [DOI: 10.32725/jab.2005.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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38
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Li SS, Forslöw A, Sundqvist KG. Autocrine Regulation of T Cell Motility by Calreticulin-Thrombospondin-1 Interaction. THE JOURNAL OF IMMUNOLOGY 2005; 174:654-61. [PMID: 15634883 DOI: 10.4049/jimmunol.174.2.654] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The mechanisms regulating T lymphocyte migration within the extracellular matrix are not understood. We show in this study that the thrombospondin-1 binding site of calreticulin, spanning aa 19-32, is a major triggering factor for T cell motility and migration within a three-dimensional collagen type 1 matrix, and that exogenous motogenic factors such as chemokines can stimulate migration via a calreticulin-thrombospondin-1 pathway. Endogenous calreticulin binding to the N-terminal domain of endogenous thrombospondin-1 elicited a motogenic signal to the T cells through the C-terminal domain of thrombospondin-1 and its cell surface receptor integrin-associated protein (CD47). Our data further revealed that thrombospondin-1 was expressed on the cell surface with a high turnover, and that PI3K and the Janus family of tyrosine kinases were required for T cell motility mediated through calreticulin, thrombospondin-1, and CD47. These results unveil an autocrine mechanism of calreticulin-thrombospondin-1-CD47 interaction for the control of T cell motility and migration within three-dimensional extracellular matrix substrata.
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Affiliation(s)
- Shu Shun Li
- Division of Clinical Immunology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden
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39
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Bedard K, Szabo E, Michalak M, Opas M. Cellular Functions of Endoplasmic Reticulum Chaperones Calreticulin, Calnexin, and ERp57. INTERNATIONAL REVIEW OF CYTOLOGY 2005; 245:91-121. [PMID: 16125546 DOI: 10.1016/s0074-7696(05)45004-4] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Glycosylated proteins destined for the cell surface or to be secreted from the cell are trafficked through the endoplasmic reticulum during synthesis and folding. Correct folding is determined in large part by the sequence of the protein, but it is also assisted by interaction with enzymes and chaperones of the endoplasmic reticulum. Calreticulin, calnexin, and ERp57 are among the endoplasmic chaperones that interact with partially folded glycoproteins and determine if the proteins are to be released from the endoplasmic reticulum to be expressed, or alternatively, if they are to be sent to the proteosome for degradation. Studies on the effect of alterations in the expression and function of these proteins are providing information about the importance of this quality control system, as well as uncovering other important functions these proteins play outside of the endoplasmic reticulum.
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Affiliation(s)
- Karen Bedard
- Membrane Protein Research Group and Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
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40
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Nomura R, Aoki T, Hagiwara H, Senda T, Fujimoto T. Anti-calreticulin Antibody Binds to a Membrane Protein in Caveolae. Acta Histochem Cytochem 2005. [DOI: 10.1267/ahc.38.43] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- Ryuji Nomura
- Department of Anatomy I, Fujita Health University School of Medicine
| | - Takeo Aoki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Haruo Hagiwara
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Takao Senda
- Department of Anatomy I, Fujita Health University School of Medicine
| | - Toyoshi Fujimoto
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine
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41
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Giannone G, Rondé P, Gaire M, Beaudouin J, Haiech J, Ellenberg J, Takeda K. Calcium rises locally trigger focal adhesion disassembly and enhance residency of focal adhesion kinase at focal adhesions. J Biol Chem 2004; 279:28715-23. [PMID: 15102844 DOI: 10.1074/jbc.m404054200] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Focal adhesion kinase (FAK) activity and Ca(2+) signaling led to a turnover of focal adhesions (FAs) required for cell spreading and migration. We used yellow Cameleon-2 (Ycam), a fluorescent protein-based Ca(2+) sensor fused to FAK or to a FAK-related non-kinase domain, to measure simultaneously local Ca(2+) variations at FA sites and FA dynamics. Discrete subcellular Ca(2+) oscillators initiate both propagating and abortive Ca(2+) waves in migrating U87 astrocytoma cells. Ca(2+)-dependent FA disassembly occurs when the Ca(2+) wave reaches individual FAs, indicating that local but not global Ca(2+) increases trigger FA disassembly. An unexpectedly rapid flux of FAK between cytosolic and FA compartments was revealed by fluorescence recovery after photobleaching studies. The FAK-Ycam recovery half-time (17 s) at FAs was slowed (to 29 s) by Ca(2+) elevation. FAK-related non-kinase domain-Ycam had a faster, Ca(2+)-insensitive recovery half-time (11 s), which is consistent with the effect of Ca(2+) on FAK-Ycam dynamics not being due to a general modification of the dynamics of FA components. Because FAK association at FAs was prolonged by Ca(2+) and FAK autophosphorylation was correlated to intracellular Ca(2+) levels, we propose that local Ca(2+) elevations increase the residency of FAK at FAs, possibly by means of tyrosine phosphorylation of FAK, thereby leading to increased activation of its effectors involved in FA disassembly.
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Affiliation(s)
- Grégory Giannone
- Laboratoire de Pharmacologie et Physicochimie des Interactions Cellulaires et Moléculaires, Unité Mixte de Recherche CNRS 7034, Université Louis Pasteur de Strasbourg, 67401 Illkirch, France
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42
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Papp S, Fadel MP, Opas M. ER-to-cell surface signalling: calreticulin and cell adhesion. J Appl Biomed 2004. [DOI: 10.32725/jab.2004.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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43
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Ferreira V, Molina MC, Valck C, Rojas A, Aguilar L, Ramírez G, Schwaeble W, Ferreira A. Role of calreticulin from parasites in its interaction with vertebrate hosts. Mol Immunol 2004; 40:1279-91. [PMID: 15128045 DOI: 10.1016/j.molimm.2003.11.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Although parasites range from protozoan to complex, evolutionary advanced arthropods, in general, a hallmark of parasite life cycles is their ability to adapt to changes in temperature, pH and host defense strategies. Calreticulin, a calcium-binding protein, highly conserved and multifunctional, is present in every cell of higher organisms, except erythrocytes. The surprising array of calreticulin-associated functions include lectin-like chaperoning, calcium storage and signaling, modulation of gene expression, cell adhesion, enhancement of phagocytosis of C1q or collectin opsonized apoptotic cells, inhibition of angiogenesis and tumoral growth, inhibition of perforin pore formation in T and NK cells, and inhibition of C1q-dependent complement activation. Likewise, calreticulin is present in a wide spectrum of sub cellular compartments. Parasite calreticulin shows a surprisingly high degree of conservation within the framework of its functional domains. Its role within the parasite/host relationship needs to be assessed further, in particular with regard to its impact on parasite infectivity, by helping to evade from its hosts' immune response. With special emphasis on calreticulin from Trypanosoma cruzi, the intracellular protozoan agent of American trypanosomiasis (Chagas' disease), we wish to exemplify and highlight the various implications of parasite calreticulin, within the pathophysiology of parasite-mediated human and animal disease.
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Affiliation(s)
- Viviana Ferreira
- Programa de Immunología, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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44
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45
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46
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Michalak M, Lynch J, Groenendyk J, Guo L, Robert Parker JM, Opas M. Calreticulin in cardiac development and pathology. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1600:32-7. [PMID: 12445456 DOI: 10.1016/s1570-9639(02)00441-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Calreticulin is a Ca(2+) binding/storage chaperone resident in the lumen of endoplasmic reticulum (ER). The protein is an important component of the calreticulin/calnexin cycle and the quality control pathways in the ER. In mice, calreticulin deficiency is lethal due to impaired cardiac development. This is not surprising because the protein is expressed at high level at early stages of cardiac development. Overexpression of the protein in developing and postnatal heart leads to bradycardia, complete heart block and sudden death. Recent studies on calreticulin-deficient and transgenic mice revealed that the protein is a key upstream regulator of calcineurin-dependent pathways during cardiac development. Calreticulin and ER may play important role in cardiac development and postnatal pathologies.
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Affiliation(s)
- Marek Michalak
- Canadian Institutes of Health Research Membrane Protein Research Group and Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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47
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Michalak M, Robert Parker JM, Opas M. Ca2+ signaling and calcium binding chaperones of the endoplasmic reticulum. Cell Calcium 2002; 32:269-78. [PMID: 12543089 DOI: 10.1016/s0143416002001884] [Citation(s) in RCA: 339] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The endoplasmic reticulum is a centrally located organelle which affects virtually every cellular function. Its unique luminal environment consists of Ca(2+) binding chaperones, which are involved in protein folding, post-translational modification, Ca(2+) storage and release, and lipid synthesis and metabolism. The environment within the lumen of the endoplasmic reticulum has profound effects on endoplasmic reticulum function and signaling, including apoptosis, stress responses, organogenesis, and transcriptional activity. Calreticulin, a major Ca(2+) binding (storage) chaperone in the endoplasmic reticulum, is a key component of the calreticulin/calnexin cycle which is responsible for the folding of newly synthesized proteins and glycoproteins and for quality control pathways in the endoplasmic reticulum. The function of calreticulin, calnexin and other endoplasmic reticulum proteins is affected by continuous fluctuations in the concentration of Ca(2+) in the endoplasmic reticulum. Thus, changes in Ca(2+) concentration may play a signaling role in the lumen of the endoplasmic reticulum as well as in the cytosol. Recent studies on calreticulin-deficient and transgenic mice have revealed that calreticulin and the endoplasmic reticulum may be upstream regulators in the Ca(2+)-dependent pathways that control cellular differentiation and/or organ development.
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Affiliation(s)
- M Michalak
- Department of Biochemistry, Canadian Institutes of Health Research Membrane Protein Research Group, University of Alberta, Alta., T6G 2H7, Edmonton, Canada.
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48
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Goicoechea S, Pallero MA, Eggleton P, Michalak M, Murphy-Ullrich JE. The anti-adhesive activity of thrombospondin is mediated by the N-terminal domain of cell surface calreticulin. J Biol Chem 2002; 277:37219-28. [PMID: 12147682 DOI: 10.1074/jbc.m202200200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thrombospondin (TSP) induces reorganization of the actin cytoskeleton and restructuring of focal adhesions through binding of amino acids (aa) 17-35 (hep I peptide) of thrombospondin to a cell surface form of calreticulin (CRT). In this report we provide further evidence for the involvement of calreticulin in thrombospondin signaling and characterize thrombospondin-calreticulin interactions. Wild type but not crt(-/-) cells respond to hep I/TSP. Responsiveness can be restored by incubation of cells with exogenous calreticulin or by transfection with calreticulin. Thrombospondin forms complexes with the CRT-N-domain that are enhanced by physiologic levels of calcium and zinc. Consistent with thrombospondin/CRT-N-domain binding, only the CRT-N-domain blocks hep I- and thrombospondin-stimulated focal adhesion disassembly. A series of glutathione S-transferase-N-domain mutants were used to map the sequence within the N-domain that interacts with TSP/hep I. A construct containing aa 1-43 but not a construct of aa 1-31 supported thrombospondin binding and focal adhesion disassembly. A series of overlapping peptides were used to further map the thrombospondin-binding site. Peptides spanning aa 19-36 (RWIESKHKSDFGKFVLSS) blocked hep I-stimulated focal adhesion disassembly, indicating that the TSP/hep I-binding site is located to this sequence in calreticulin. A mutant fusion protein lacking aa 19-36 (glutathione S-transferase-CRTDeltahep I) failed to restore responsiveness to hep I in crt(-/-) cells, bind thrombospondin, or competitively block focal adhesion disassembly, providing evidence for the role of this calreticulin sequence in mediating thrombospondin signaling.
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Affiliation(s)
- Silvia Goicoechea
- Department of Pathology, Division of Molecular and Cellular Pathology and Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019, USA
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49
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Müller-Taubenberger A, Lupas AN, Li H, Ecke M, Simmeth E, Gerisch G. Calreticulin and calnexin in the endoplasmic reticulum are important for phagocytosis. EMBO J 2001; 20:6772-82. [PMID: 11726513 PMCID: PMC125758 DOI: 10.1093/emboj/20.23.6772] [Citation(s) in RCA: 188] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Calreticulin and calnexin are Ca2+-binding proteins with chaperone activity in the endoplasmic reticulum. These proteins have been eliminated by gene replacement in Dictyostelium, the only microorganism known to harbor both proteins; family members in Dictyostelium are located at the base of phylogenetic trees. A dramatic decline in the rate of phagocytosis was observed in double mutants lacking calreticulin and calnexin, whereas only mild changes occurred in single mutants. Dictyostelium cells are professional phagocytes, capable of internalizing particles by a sequence of activities: adhesion of the particle to the cell surface, actin-dependent outgrowth of a phagocytic cup, and separation of the phagosome from the plasma membrane. In the double-null mutants, particles still adhered to the cell surface, but the outgrowth of phagocytic cups was compromised. Green fluorescent protein-tagged calreticulin and calnexin, expressed in wild-type cells, revealed a direct link of the endoplasmic reticulum to the phagocytic cup enclosing a particle, such that the Ca2+ storage capacity of calreticulin and calnexin might directly modulate activities of the actin system during particle uptake.
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Affiliation(s)
| | - Andrei N. Lupas
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany and
SmithKline Beecham Pharmaceuticals UP1345, 1250 South Collegeville Road, Collegeville, PA 19426-0989, USA Present address: MPI für Entwicklungsbiologie, D-72076 Tübingen, Germany Corresponding author e-mail:
| | | | | | | | - Günther Gerisch
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany and
SmithKline Beecham Pharmaceuticals UP1345, 1250 South Collegeville Road, Collegeville, PA 19426-0989, USA Present address: MPI für Entwicklungsbiologie, D-72076 Tübingen, Germany Corresponding author e-mail:
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50
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Fadel MP, Szewczenko-Pawlikowski M, Leclerc P, Dziak E, Symonds JM, Blaschuk O, Michalak M, Opas M. Calreticulin affects beta-catenin-associated pathways. J Biol Chem 2001; 276:27083-9. [PMID: 11369768 DOI: 10.1074/jbc.m101676200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Calreticulin, a Ca(2+) storage protein and chaperone in the endoplasmic reticulum, also modulates cell adhesiveness. Overexpression of calreticulin correlates with (i) increased cell adhesiveness, (ii) increased expression of N-cadherin and vinculin, and (iii) decreased protein phosphorylation on tyrosine. Among proteins that are dephosphorylated in cells that overexpress calreticulin is beta-catenin, a structural component of cadherin-dependent adhesion complexes, a member of the armadillo family of proteins and a part of the Wnt signaling pathway. We postulate that the changes in cell adhesiveness may be due to calreticulin-mediated effects on a signaling pathway from the endoplasmic reticulum, which impinges on the Wnt signaling pathway via the cadherin/catenin protein system and involves changes in the activity of protein-tyrosine kinases and/or phosphatases.
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Affiliation(s)
- M P Fadel
- Department of Anatomy and Cell Biology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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