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Hütz K, Zeiler J, Sachs L, Ormanns S, Spindler V. Loss of desmoglein 2 promotes tumorigenic behavior in pancreatic cancer cells. Mol Carcinog 2017; 56:1884-1895. [PMID: 28277619 DOI: 10.1002/mc.22644] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 02/17/2017] [Accepted: 03/03/2017] [Indexed: 12/31/2022]
Abstract
The ability to maintain cell-cell adhesion is crucial for tissue integrity and organization. Accordingly, loss of cohesiveness plays a critical role in cancer invasion and metastasis. Desmosomes are cell junctions providing strong intercellular adhesive strength and dysregulation of desmosomal constituents contributes to cancer progression through altered cell signaling pathways. Here, we focused on the desmosomal adhesion molecules Desmoglein 2 (Dsg2) and Desmocollin 2 (Dsc2), and their contribution to migration and invasion in pancreatic cancer cells. Silencing of Dsg2 but not Dsc2 resulted in loss of cell cohesion and enhanced migration, and invasion of pancreatic adenocarcinoma cells. To identify potential pathways regulated by Dsg2, we performed kinase arrays and detected the activity of ERK and growth factor receptors to be significantly enhanced in Dsg2-deficient cells. Consequently, inhibition of ERK phosphorylation in Dsg2 knockdown cells normalized migration. Loss of Dsg2 resulted in reduced levels of the desmosomal adapter protein and transcriptional regulator Plakoglobin (PG) in an ERK-dependent manner, whereas other desmosomal molecules were not altered. Overexpression of PG rescued enhanced migration induced by silencing of Dsg2. These results identify a novel pro-migratory pathway of pancreatic cancer cells in which loss of Dsg2 reduces the levels of PG via deregulated MAPK signaling.
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Affiliation(s)
- Katharina Hütz
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Julian Zeiler
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Lena Sachs
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Steffen Ormanns
- Institute of Pathology, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Volker Spindler
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität Munich, Munich, Germany
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Brodehl A, Belke DD, Garnett L, Martens K, Abdelfatah N, Rodriguez M, Diao C, Chen YX, Gordon PMK, Nygren A, Gerull B. Transgenic mice overexpressing desmocollin-2 (DSC2) develop cardiomyopathy associated with myocardial inflammation and fibrotic remodeling. PLoS One 2017; 12:e0174019. [PMID: 28339476 PMCID: PMC5365111 DOI: 10.1371/journal.pone.0174019] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 03/02/2017] [Indexed: 12/16/2022] Open
Abstract
Background Arrhythmogenic cardiomyopathy is an inherited heart muscle disorder leading to ventricular arrhythmias and heart failure, mainly as a result of mutations in cardiac desmosomal genes. Desmosomes are cell-cell junctions mediating adhesion of cardiomyocytes; however, the molecular and cellular mechanisms underlying the disease remain widely unknown. Desmocollin-2 is a desmosomal cadherin serving as an anchor molecule required to reconstitute homeostatic intercellular adhesion with desmoglein-2. Cardiac specific lack of desmoglein-2 leads to severe cardiomyopathy, whereas overexpression does not. In contrast, the corresponding data for desmocollin-2 are incomplete, in particular from the view of protein overexpression. Therefore, we developed a mouse model overexpressing desmocollin-2 to determine its potential contribution to cardiomyopathy and intercellular adhesion pathology. Methods and results We generated transgenic mice overexpressing DSC2 in cardiac myocytes. Transgenic mice developed a severe cardiac dysfunction over 5 to 13 weeks as indicated by 2D-echocardiography measurements. Corresponding histology and immunohistochemistry demonstrated fibrosis, necrosis and calcification which were mainly localized in patches near the epi- and endocardium of both ventricles. Expressions of endogenous desmosomal proteins were markedly reduced in fibrotic areas but appear to be unchanged in non-fibrotic areas. Furthermore, gene expression data indicate an early up-regulation of inflammatory and fibrotic remodeling pathways between 2 to 3.5 weeks of age. Conclusion Cardiac specific overexpression of desmocollin-2 induces necrosis, acute inflammation and patchy cardiac fibrotic remodeling leading to fulminant biventricular cardiomyopathy.
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Affiliation(s)
- Andreas Brodehl
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Darrell D. Belke
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Lauren Garnett
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Kristina Martens
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Nelly Abdelfatah
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Marcela Rodriguez
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Schulich School of Engineering, University of Calgary, Calgary, Alberta, Canada
| | - Catherine Diao
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Yong-Xiang Chen
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Paul M. K. Gordon
- Alberta Children's Hospital Research Institute Genomics and Bioinformatics Facility, University of Calgary, Calgary, Alberta, Canada
| | - Anders Nygren
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Schulich School of Engineering, University of Calgary, Calgary, Alberta, Canada
| | - Brenda Gerull
- Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany
- * E-mail:
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Tanaka T, Goto K, Iino M. Diverse Functions and Signal Transduction of the Exocyst Complex in Tumor Cells. J Cell Physiol 2016; 232:939-957. [DOI: 10.1002/jcp.25619] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 09/23/2016] [Indexed: 12/11/2022]
Affiliation(s)
- Toshiaki Tanaka
- Department of Anatomy and Cell Biology; School of Medicine; Yamagata University; Yamagata Japan
- Department of Dentistry, Oral and Maxillofacial Surgery; Plastic and Reconstructive Surgery; School of Medicine; Yamagata University; Yamagata Japan
| | - Kaoru Goto
- Department of Anatomy and Cell Biology; School of Medicine; Yamagata University; Yamagata Japan
| | - Mitsuyoshi Iino
- Department of Dentistry, Oral and Maxillofacial Surgery; Plastic and Reconstructive Surgery; School of Medicine; Yamagata University; Yamagata Japan
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Ebert LM, Tan LY, Johan MZ, Min KKM, Cockshell MP, Parham KA, Betterman KL, Szeto P, Boyle S, Silva L, Peng A, Zhang Y, Ruszkiewicz A, Zannettino ACW, Gronthos S, Koblar S, Harvey NL, Lopez AF, Shackleton M, Bonder CS. A non-canonical role for desmoglein-2 in endothelial cells: implications for neoangiogenesis. Angiogenesis 2016; 19:463-86. [PMID: 27338829 PMCID: PMC5026727 DOI: 10.1007/s10456-016-9520-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 06/11/2016] [Indexed: 01/06/2023]
Abstract
Desmogleins (DSG) are a family of cadherin adhesion proteins that were first identified in desmosomes and provide cardiomyocytes and epithelial cells with the junctional stability to tolerate mechanical stress. However, one member of this family, DSG2, is emerging as a protein with additional biological functions on a broader range of cells. Here we reveal that DSG2 is expressed by non-desmosome-forming human endothelial progenitor cells as well as their mature counterparts [endothelial cells (ECs)] in human tissue from healthy individuals and cancer patients. Analysis of normal blood and bone marrow showed that DSG2 is also expressed by CD34+CD45dim hematopoietic progenitor cells. An inability to detect other desmosomal components, i.e., DSG1, DSG3 and desmocollin (DSC)2/3, on these cells supports a solitary role for DSG2 outside of desmosomes. Functionally, we show that CD34+CD45dimDSG2+ progenitor cells are multi-potent and pro-angiogenic in vitro. Using a ‘knockout-first’ approach, we generated a Dsg2 loss-of-function strain of mice (Dsg2lo/lo) and observed that, in response to reduced levels of Dsg2: (i) CD31+ ECs in the pancreas are hypertrophic and exhibit altered morphology, (ii) bone marrow-derived endothelial colony formation is impaired, (iii) ex vivo vascular sprouting from aortic rings is reduced, and (iv) vessel formation in vitro and in vivo is attenuated. Finally, knockdown of DSG2 in a human bone marrow EC line reveals a reduction in an in vitro angiogenesis assay as well as relocalisation of actin and VE-cadherin away from the cell junctions, reduced cell–cell adhesion and increased invasive properties by these cells. In summary, we have identified DSG2 expression in distinct progenitor cell subpopulations and show that, independent from its classical function as a component of desmosomes, this cadherin also plays a critical role in the vasculature.
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Affiliation(s)
- Lisa M Ebert
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Lih Y Tan
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - M Zahied Johan
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Kay Khine Myo Min
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Michaelia P Cockshell
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Kate A Parham
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Kelly L Betterman
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Paceman Szeto
- Cancer Development and Treatment Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, Melbourne, VIC, Australia.,Department of Pathology, University of Melbourne, Melbourne, VIC, Australia
| | - Samantha Boyle
- Cancer Development and Treatment Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, Melbourne, VIC, Australia.,Department of Pathology, University of Melbourne, Melbourne, VIC, Australia
| | - Lokugan Silva
- Cancer Development and Treatment Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, Melbourne, VIC, Australia.,Department of Pathology, University of Melbourne, Melbourne, VIC, Australia
| | - Angela Peng
- Cancer Development and Treatment Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, Melbourne, VIC, Australia.,Department of Pathology, University of Melbourne, Melbourne, VIC, Australia
| | - YouFang Zhang
- Cancer Development and Treatment Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, Melbourne, VIC, Australia.,Department of Pathology, University of Melbourne, Melbourne, VIC, Australia
| | - Andrew Ruszkiewicz
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Andrew C W Zannettino
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia.,Adelaide Medical School, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Stan Gronthos
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia.,Adelaide Medical School, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Simon Koblar
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia.,Adelaide Medical School, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Natasha L Harvey
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia
| | - Angel F Lopez
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia.,Adelaide Medical School, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Mark Shackleton
- Cancer Development and Treatment Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, Melbourne, VIC, Australia.,Department of Pathology, University of Melbourne, Melbourne, VIC, Australia
| | - Claudine S Bonder
- Centre for Cancer Biology, University of South Australia and SA Pathology, PO Box 14, Rundle Mall, Adelaide, SA, 5000, Australia. .,Adelaide Medical School, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia.
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Chelko SP, Asimaki A, Andersen P, Bedja D, Amat-Alarcon N, DeMazumder D, Jasti R, MacRae CA, Leber R, Kleber AG, Saffitz JE, Judge DP. Central role for GSK3β in the pathogenesis of arrhythmogenic cardiomyopathy. JCI Insight 2016; 1:85923. [PMID: 27170944 DOI: 10.1172/jci.insight.85923] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Arrhythmogenic cardiomyopathy (ACM) is characterized by redistribution of junctional proteins, arrhythmias, and progressive myocardial injury. We previously reported that SB216763 (SB2), annotated as a GSK3β inhibitor, reverses disease phenotypes in a zebrafish model of ACM. Here, we show that SB2 prevents myocyte injury and cardiac dysfunction in vivo in two murine models of ACM at baseline and in response to exercise. SB2-treated mice with desmosome mutations showed improvements in ventricular ectopy and myocardial fibrosis/inflammation as compared with vehicle-treated (Veh-treated) mice. GSK3β inhibition improved left ventricle function and survival in sedentary and exercised Dsg2mut/mut mice compared with Veh-treated Dsg2mut/mut mice and normalized intercalated disc (ID) protein distribution in both mutant mice. GSK3β showed diffuse cytoplasmic localization in control myocytes but ID redistribution in ACM mice. Identical GSK3β redistribution is present in ACM patient myocardium but not in normal hearts or other cardiomyopathies. SB2 reduced total GSK3β protein levels but not phosphorylated Ser 9-GSK3β in ACM mice. Constitutively active GSK3β worsens ACM in mutant mice, while GSK3β shRNA silencing in ACM cardiomyocytes prevents abnormal ID protein distribution. These results highlight a central role for GSKβ in the complex phenotype of ACM and provide further evidence that pharmacologic GSKβ inhibition improves cardiomyopathies due to desmosome mutations.
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Affiliation(s)
- Stephen P Chelko
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Angeliki Asimaki
- Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Peter Andersen
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Djahida Bedja
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Australian School of Advanced Medicine, Macquarie University, Sydney, New South Wales, Australia
| | - Nuria Amat-Alarcon
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Deeptankar DeMazumder
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ravirasmi Jasti
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Calum A MacRae
- Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Remo Leber
- Schiller AG, Research and Development, Baar, Switzerland
| | - Andre G Kleber
- Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Jeffrey E Saffitz
- Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Daniel P Judge
- Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Peri-implantation lethality in mice carrying megabase-scale deletion on 5qc3.3 is caused by Exoc1 null mutation. Sci Rep 2015; 5:13632. [PMID: 26346620 PMCID: PMC4562154 DOI: 10.1038/srep13632] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 08/03/2015] [Indexed: 01/28/2023] Open
Abstract
We found a novel spontaneous mouse mutant with depigmentation in the ventral body, which we called White Spotting (WS) mouse. Genetic investigation revealed deletion of a > 1.2-Mb genomic region containing nine genes (Kit, Kdr, Srd5a3, Tmeme165, Clock, Pdcl2, Nmu, Exoc1, and Cep135). We designated this mutant allele KitWS. Interestingly, homozygous mutants (KitWS/WS) showed a peri-implantation lethal phenotype. Expression analyses of these nine genes in blastocysts suggested that Exoc1 was a prime candidate for this phenotype. We produced Exoc1 knockout mice, and the same peri-implantation lethal phenotype was seen in Exoc1−/− embryos. In addition, the polygenic effect without Exoc1 was investigated in genome-edited KitWE mice carrying the Mb-scale deletion induced by the CRISPR/Cas9 system. As KitWE/WE embryos did not exhibit the abnormal phenotype, which was seen in KitWS/WS. We concluded that peri-implantation lethality in KitWS/WS was caused by a monogenic defect of Exoc1.
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Cody JD, Sebold C, Heard P, Carter E, Soileau B, Hasi-Zogaj M, Hill A, Rupert D, Perry B, O'Donnell L, Gelfond J, Lancaster J, Fox PT, Hale DE. Consequences of chromsome18q deletions. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2015; 169:265-80. [PMID: 26235940 DOI: 10.1002/ajmg.c.31446] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 06/28/2015] [Indexed: 11/11/2022]
Abstract
Providing clinically relevant prognoses and treatment information for people with a chromsome18q deletion is particularly challenging because every unrelated person has a unique region of hemizygosity. The hemizygous region can involve almost any region of 18q including between 1 and 101 genes (30 Mb of DNA). Most individuals have terminal deletions, but in our cohort of over 350 individuals 23% have interstitial deletions. Because of this heterogeneity, we take a gene by gene approach to understanding the clinical consequences. There are 196 genes on 18q. We classified 133 of them as dosage insensitive, 15 (8%) as dosage sensitive leading to haploinsufficiency while another 10 (5%) have effects that are conditionally haploinsufficient and are dependent on another factor, genetic or environmental in order to cause an abnormal phenotype. Thirty-seven genes (19%) have insufficient information to classify their dosage effect. Phenotypes attributed to single genes include: congenital heart disease, minor bone morphology changes, central nervous system dysmyelination, expressive speech delay, vesicouretreral reflux, polyposis, Pitt-Hopkins syndrome, intellectual disability, executive function impairment, male infertility, aural atresia, and high frequency sensorineural hearing loss. Additionally, identified critical regions for other phenotypes include: adolescent idiopathic scoliosis and pectus excavatum, Virchow-Robin perivascular spaces, small corpus callosum, strabismus, atopic disorders, mood disorder, IgA deficiency, nystagmus, congenital heart disease, kidney malformation, vertical talus, CNS dysmyelination growth hormone deficiency and cleft palate. Together these findings make it increasingly feasible to compile an individualized syndrome description based on each person's individuated genotype. Future work will focus on understanding molecular mechanisms leading to treatment.
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Kant S, Holthöfer B, Magin TM, Krusche CA, Leube RE. Desmoglein 2-Dependent Arrhythmogenic Cardiomyopathy Is Caused by a Loss of Adhesive Function. ACTA ACUST UNITED AC 2015; 8:553-63. [PMID: 26085008 DOI: 10.1161/circgenetics.114.000974] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 06/09/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND The desmosomal cadherin desmoglein 2 (Dsg2) localizes to the intercalated disc coupling adjacent cardiomyocytes. Desmoglein 2 gene (DSG2) mutations cause arrhythmogenic cardiomyopathy (AC) in human and transgenic mice. AC is characterized by arrhythmia, cardiodilation, cardiomyocyte necrosis with replacement fibrosis, interstitial fibrosis, and intercalated disc dissociation. The genetic DSG2 constellations encountered are compatible with loss of adhesion and altered signaling. To further elucidate pathomechanisms, we examined whether heart-specific Dsg2 depletion triggers cardiomyopathy. METHODS AND RESULTS Because DSG2 knockouts die during early embryogenesis, mice were prepared with cardiomyocyte-specific DSG2 ablation. Healthy transgenic animals were born with a functional heart presenting intercalated discs with incorporated desmosomal proteins. Dsg2 protein expression was reduced below 3% in the heart. All animals developed AC during postnatal growth with pronounced chamber dilation, calcifying cardiomyocyte necrosis, aseptic inflammation, interstitial and focal replacement fibrosis, and conduction defects with altered connexin 43 distribution. Electron microscopy revealed absence of desmosome-like structures and regional loss of intercalated disc adhesion. Mice carrying 2 mutant DSG2 alleles coding for Dsg2 lacking part of the adhesive EC1-EC2 domains present an indistinguishable phenotype, which is similar to that observed in human AC patients. CONCLUSIONS The observations show that the presence of Dsg2 is not essential for late heart morphogenesis and for cardiac contractility to support postnatal life. On increasing mechanical demands, heart function is severely compromised as evidenced by the onset of cardiomyopathy with pronounced morphological alterations. We propose that loss of Dsg2 compromises adhesion, and that this is a major pathogenic mechanism in DSG2-related and probably other desmosome-related ACs.
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Affiliation(s)
- Sebastian Kant
- From the Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany (S.K., B.H., C.A.K., R.E.L.); and Institute of Biology and Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany (T.M.M.)
| | - Bastian Holthöfer
- From the Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany (S.K., B.H., C.A.K., R.E.L.); and Institute of Biology and Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany (T.M.M.)
| | - Thomas M Magin
- From the Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany (S.K., B.H., C.A.K., R.E.L.); and Institute of Biology and Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany (T.M.M.)
| | - Claudia A Krusche
- From the Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany (S.K., B.H., C.A.K., R.E.L.); and Institute of Biology and Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany (T.M.M.)
| | - Rudolf E Leube
- From the Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany (S.K., B.H., C.A.K., R.E.L.); and Institute of Biology and Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany (T.M.M.).
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Abstract
The arrival of multicellularity in evolution facilitated cell-cell signaling in conjunction with adhesion. As the ectodomains of cadherins interact with each other directly in trans (as well as in cis), spanning the plasma membrane and associating with multiple other entities, cadherins enable the transduction of "outside-in" or "inside-out" signals. We focus this review on signals that originate from the larger family of cadherins that are inwardly directed to the nucleus, and thus have roles in gene control or nuclear structure-function. The nature of cadherin complexes varies considerably depending on the type of cadherin and its context, and we will address some of these variables for classical cadherins versus other family members. Substantial but still fragmentary progress has been made in understanding the signaling mediators used by varied cadherin complexes to coordinate the state of cell-cell adhesion with gene expression. Evidence that cadherin intracellular binding partners also localize to the nucleus is a major point of interest. In some models, catenins show reduced binding to cadherin cytoplasmic tails favoring their engagement in gene control. When bound, cadherins may serve as stoichiometric competitors of nuclear signals. Cadherins also directly or indirectly affect numerous signaling pathways (e.g., Wnt, receptor tyrosine kinase, Hippo, NFκB, and JAK/STAT), enabling cell-cell contacts to touch upon multiple biological outcomes in embryonic development and tissue homeostasis.
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Affiliation(s)
- Pierre D McCrea
- Department of Genetics, University of Texas MD Anderson Cancer Center; Program in Genes & Development, Graduate School in Biomedical Sciences, Houston, Texas, USA.
| | - Meghan T Maher
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Cara J Gottardi
- Cellular and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA; Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
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Kountikov EI, Poe JC, Maclver NJ, Rathmell JC, Tedder TF. A spontaneous deletion within the desmoglein 3 extracellular domain of mice results in hypomorphic protein expression, immunodeficiency, and a wasting disease phenotype. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 185:617-30. [PMID: 25542773 DOI: 10.1016/j.ajpath.2014.10.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 10/17/2014] [Accepted: 10/23/2014] [Indexed: 01/03/2023]
Abstract
Desmoglein 3 is a transmembrane component of desmosome complexes that mediate epidermal cell-to-cell adhesion and tissue integrity. Antibody blockade of desmoglein 3 function in pemphigus vulgaris patients leads to skin blistering (acantholysis) and oral mucosa lesions. Desmoglein 3 deficiency in mice leads to a phenotype characterized by cyclic alopecia in addition to the dramatic skin and mucocutaneous acantholysis observed in pemphigus patients. In this study, mice that developed an overt squeaky (sqk) phenotype were identified with obstructed airways, cyclic hair loss, and severe immunodeficiency subsequent to the development of oral lesions and malnutrition. Single-nucleotide polymorphism-based quantitative trait loci mapping revealed a genetic deletion that resulted in expression of a hypomorphic desmoglein 3 protein with a truncation of an extracellular cadherin domain. Because hypomorphic expression of a truncated desmoglein 3 protein led to a spectrum of severe pathology not observed in mice deficient in desmoglein 3, similar human genetic alterations may also disrupt desmosome function and induce a disease course distinct from pathogenesis of pemphigus vulgaris.
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Affiliation(s)
- Evgueni I Kountikov
- Department of Immunology, Duke University Medical Center, Durham, North Carolina
| | - Jonathan C Poe
- Department of Immunology, Duke University Medical Center, Durham, North Carolina
| | - Nancie J Maclver
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina
| | - Jeffrey C Rathmell
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina
| | - Thomas F Tedder
- Department of Immunology, Duke University Medical Center, Durham, North Carolina.
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Johnson JL, Najor NA, Green KJ. Desmosomes: regulators of cellular signaling and adhesion in epidermal health and disease. Cold Spring Harb Perspect Med 2014; 4:a015297. [PMID: 25368015 DOI: 10.1101/cshperspect.a015297] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Desmosomes are intercellular junctions that mediate cell-cell adhesion and anchor the intermediate filament network to the plasma membrane, providing mechanical resilience to tissues such as the epidermis and heart. In addition to their critical roles in adhesion, desmosomal proteins are emerging as mediators of cell signaling important for proper cell and tissue functions. In this review we highlight what is known about desmosomal proteins regulating adhesion and signaling in healthy skin-in morphogenesis, differentiation and homeostasis, wound healing, and protection against environmental damage. We also discuss how human diseases that target desmosome molecules directly or interfere indirectly with these mechanical and signaling functions to contribute to pathogenesis.
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Affiliation(s)
- Jodi L Johnson
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611 Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Nicole A Najor
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Kathleen J Green
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611 Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
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Dudley JS, Murphy CR, Thompson MB, McAllan BM. Desmoglein-2 during pregnancy and its role in the evolution of viviparity in a marsupial (Sminthopsis crassicaudata; Dasyuridae). J Morphol 2014; 276:261-72. [DOI: 10.1002/jmor.20333] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 09/28/2014] [Accepted: 10/02/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Jessica S. Dudley
- School of Medical Sciences and Bosch Institute; University of Sydney; Sydney NSW 2006 Australia
| | - Christopher R. Murphy
- School of Medical Sciences and Bosch Institute; University of Sydney; Sydney NSW 2006 Australia
| | - Michael B. Thompson
- School of Biological Science (A08); University of Sydney; Sydney NSW 2006 Australia
| | - Bronwyn M. McAllan
- School of Medical Sciences and Bosch Institute; University of Sydney; Sydney NSW 2006 Australia
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64
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Abstract
Desmosomes are intercellular junctions that provide strong adhesion or hyper-adhesion in tissues. Here, we discuss the molecular and structural basis of this with particular reference to the desmosomal cadherins (DCs), their isoforms and evolution. We also assess the role of DCs as regulators of epithelial differentiation. New data on the role of desmosomes in development and human disease, especially wound healing and pemphigus, are briefly discussed, and the importance of regulation of the adhesiveness of desmosomes in tissue dynamics is considered.
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Affiliation(s)
- Mohamed Berika
- Department of Anatomy, Faculty of Medicine, Mansoura University , Mansoura City , Egypt
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65
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Abstract
Desmosomes are morphologically and biochemically defined cell-cell junctions that are required for maintaining the mechanical integrity of skin and the heart in adult mammals. Furthermore, since mice with null mutations in desmosomal plaque proteins (plakoglobin and desmoplakin) die in utero, it is also evident that desmosomes are indispensable for normal embryonic development. This review focuses on the role of desmosomes in vivo. We will summarize the effects of mutations in desmosomal genes on pre- and post-embryonic development of mouse and man and discuss recent findings relating to the specific role of desmosomal cadherins in skin differentiation and homeostasis.
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Affiliation(s)
- Xing Cheng
- Department of Dermatology, Baylor College of Medicine, Houston, TX 77030, USA
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66
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Patel DM, Green KJ. Desmosomes in the Heart: A Review of Clinical and Mechanistic Analyses. ACTA ACUST UNITED AC 2014; 21:109-28. [DOI: 10.3109/15419061.2014.906533] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Lowndes M, Rakshit S, Shafraz O, Borghi N, Harmon RM, Green KJ, Sivasankar S, Nelson WJ. Different roles of cadherins in the assembly and structural integrity of the desmosome complex. J Cell Sci 2014; 127:2339-50. [PMID: 24610950 DOI: 10.1242/jcs.146316] [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: 12/12/2022] Open
Abstract
Adhesion between cells is established by the formation of specialized intercellular junctional complexes, such as desmosomes. Desmosomes contain isoforms of two members of the cadherin superfamily of cell adhesion proteins, desmocollins (Dsc) and desmogleins (Dsg), but their combinatorial roles in desmosome assembly are not understood. To uncouple desmosome assembly from other cell-cell adhesion complexes, we used micro-patterned substrates of Dsc2aFc and/or Dsg2Fc and collagen IV; we show that Dsc2aFc, but not Dsg2Fc, was necessary and sufficient to recruit desmosome-specific desmoplakin into desmosome puncta and produce strong adhesive binding. Single-molecule force spectroscopy showed that monomeric Dsc2a, but not Dsg2, formed Ca(2+)-dependent homophilic bonds, and that Dsg2 formed Ca(2+)-independent heterophilic bonds with Dsc2a. A W2A mutation in Dsc2a inhibited Ca(2+)-dependent homophilic binding, similar to classical cadherins, and Dsc2aW2A, but not Dsg2W2A, was excluded from desmosomes in MDCK cells. These results indicate that Dsc2a, but not Dsg2, is required for desmosome assembly through homophilic Ca(2+)- and W2-dependent binding, and that Dsg2 might be involved later in regulating a switch to Ca(2+)-independent adhesion in mature desmosomes.
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Affiliation(s)
- Molly Lowndes
- Cancer Biology Program, Stanford University, Stanford, CA 94305, USA
| | - Sabyasachi Rakshit
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA Ames Laboratory, United States Department of Energy, Ames, IA 50011, USA
| | - Omer Shafraz
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA Ames Laboratory, United States Department of Energy, Ames, IA 50011, USA
| | - Nicolas Borghi
- Institut Jacques Monod, Unité Mixte de Recherche 7592, Centre National de la Recherche Scientifique, and Université Paris-Diderot, 75013 Paris, France
| | - Robert M Harmon
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Kathleen J Green
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Sanjeevi Sivasankar
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA Ames Laboratory, United States Department of Energy, Ames, IA 50011, USA
| | - W James Nelson
- Cancer Biology Program, Stanford University, Stanford, CA 94305, USA Department of Biology, Stanford University, Stanford, CA 94305, USA Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
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68
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Jiang K, Rankin CR, Nava P, Sumagin R, Kamekura R, Stowell SR, Feng M, Parkos CA, Nusrat A. Galectin-3 regulates desmoglein-2 and intestinal epithelial intercellular adhesion. J Biol Chem 2014; 289:10510-10517. [PMID: 24567334 DOI: 10.1074/jbc.m113.538538] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The desmosomal cadherins, desmogleins, and desmocollins mediate strong intercellular adhesion. Human intestinal epithelial cells express the desmoglein-2 isoform. A proteomic screen for Dsg2-associated proteins in intestinal epithelial cells identified a lectin referred to as galectin-3 (Gal3). Gal3 bound to N-linked β-galactosides in Dsg2 extracellular domain and co-sedimented with caveolin-1 in lipid rafts. Down-regulation of Gal3 protein or incubation with lactose, a galactose-containing disaccharide that competitively inhibits galectin binding to Dsg2, decreased intercellular adhesion in intestinal epithelial cells. In the absence of functional Gal3, Dsg2 protein was internalized from the plasma membrane and degraded in the proteasome. These results report a novel role of Gal3 in stabilizing a desmosomal cadherin and intercellular adhesion in intestinal epithelial cells.
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Affiliation(s)
- Kun Jiang
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Carl R Rankin
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Porfirio Nava
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322; Department of Physiology, Biophysics and Neuroscience, CINVESTAV IPN., Av. IPN 2508, Col. San Pedro Zacatenco, 07360 Ciudad de México, Distrito Federal, México
| | - Ronen Sumagin
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Ryuta Kamekura
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Sean R Stowell
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Mingli Feng
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Charles A Parkos
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322
| | - Asma Nusrat
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology and Mucosal Inflammation Research Unit, Emory University, Atlanta, Georgia 30322.
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69
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Peitsch WK, Doerflinger Y, Fischer-Colbrie R, Huck V, Bauer AT, Utikal J, Goerdt S, Schneider SW. Desmoglein 2 depletion leads to increased migration and upregulation of the chemoattractant secretoneurin in melanoma cells. PLoS One 2014; 9:e89491. [PMID: 24558503 PMCID: PMC3928442 DOI: 10.1371/journal.pone.0089491] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Accepted: 01/23/2014] [Indexed: 12/21/2022] Open
Abstract
During development and progression of malignant melanoma, an important role has been attributed to alterations of cell-cell adhesions, in particular, to a “cadherin switch” from E- to N-cadherin. We have previously shown that a subtype of melanoma cells express the desmosomal cadherin desmoglein 2 as non-junction-bound cell surface protein in addition to classical cadherins. To study the role of desmoglein 2 in melanoma cells, melanoma lines containing high endogenous amounts of desmoglein 2 were depleted of the protein by RNA interference. Transwell migration and scratch wounding assays showed markedly increased migration upon desmoglein 2 suppression whereas proliferation and viability remained unaltered. In gene expression profiles, desmoglein 2 depletion was associated with overexpression of migration-related genes. Strongest overexpression was found for secretogranin II which has not been reported in melanoma cells before. The bioactive peptide derived from secretogranin II, secretoneurin, is known to exert chemoattractive functions and was demonstrated here to stimulate melanoma cell migration. In summary, we show that desmoglein 2 expression attenuates migration of melanoma cells. The mechanism of desmoglein 2 impaired cell migration is mediated by downregulation of secretogranin II. Loss of desmoglein 2 increases expression of secretogranin II, followed by an enhanced migratory activity of melanoma cells. Our data add a new pathway of regulating melanoma cell migration related to a desmoglein 2 – secretogranin II axis.
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Affiliation(s)
- Wiebke K. Peitsch
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- * E-mail:
| | - Yvette Doerflinger
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Volker Huck
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
| | - Alexander T. Bauer
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
| | - Jochen Utikal
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
- Skin Cancer Unit, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sergij Goerdt
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan W. Schneider
- Department of Dermatology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
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70
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Waschke J, Spindler V. Desmosomes and Extradesmosomal Adhesive Signaling Contacts in Pemphigus. Med Res Rev 2014; 34:1127-45. [DOI: 10.1002/med.21310] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Jens Waschke
- Institute of Anatomy and Cell Biology, Department I; Ludwig-Maximilians-Universität (LMU) Munich; Pettenkoferstrasse 11 D-80336 Munich Germany
| | - Volker Spindler
- Institute of Anatomy and Cell Biology, Department I; Ludwig-Maximilians-Universität (LMU) Munich; Pettenkoferstrasse 11 D-80336 Munich Germany
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71
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Abstract
Desmosomes anchor intermediate filaments at sites of cell contact established by the interaction of cadherins extending from opposing cells. The incorporation of cadherins, catenin adaptors, and cytoskeletal elements resembles the closely related adherens junction. However, the recruitment of intermediate filaments distinguishes desmosomes and imparts a unique function. By linking the load-bearing intermediate filaments of neighboring cells, desmosomes create mechanically contiguous cell sheets and, in so doing, confer structural integrity to the tissues they populate. This trait and a well-established role in human disease have long captured the attention of cell biologists, as evidenced by a publication record dating back to the mid-1860s. Likewise, emerging data implicating the desmosome in signaling events pertinent to organismal development, carcinogenesis, and genetic disorders will secure a prominent role for desmosomes in future biological and biomedical investigations.
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Affiliation(s)
- Robert M Harmon
- Department of Pathology, Northwestern University Feinberg, School of Medicine , Chicago, IL , USA
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72
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Abstract
Desmogleins (Dsgs) are calcium-dependent, transmembrane glycoproteins belonging to the desmosomal cadherin superfamily, which play significant roles in selective calcium ions (Ca2+) dependent adhesion interactions between cell surfaces. Four subtypes of Dsg have been identified. Recent observations show the distribution of Dsgs can correlate with specific types of keratinization, anchorage of the hair, and hypotrichosis.
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Affiliation(s)
- Pramod Kumar Nigam
- Department of Dermatology and STD, Pt. J.N.M. Medical College, Raipur, Chhattisgarh, India
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73
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Nekrasova O, Green KJ. Desmosome assembly and dynamics. Trends Cell Biol 2013; 23:537-46. [PMID: 23891292 DOI: 10.1016/j.tcb.2013.06.004] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 06/14/2013] [Accepted: 06/17/2013] [Indexed: 01/06/2023]
Abstract
Desmosomes are intercellular junctions that anchor intermediate filaments (IFs) to the plasma membrane, forming a supracellular scaffold that provides mechanical resilience to tissues. This anchoring function is accomplished by specialized members of the cadherin family and associated cytoskeletal linking proteins, which together form a highly organized membrane core flanked by mirror-image cytoplasmic plaques. Due to the biochemical insolubility of desmosomes, the mechanisms that govern assembly of these components into a functional organelle remained elusive. Recently developed molecular reporters and live cell imaging approaches have provided powerful new tools to monitor this finely tuned process in real time. Here we discuss studies that are beginning to decipher the machinery and regulation governing desmosome assembly and homeostasis in situ and how these mechanisms are affected during disease pathogenesis.
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Affiliation(s)
- Oxana Nekrasova
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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74
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Desmoglein 2 is less important than desmoglein 3 for keratinocyte cohesion. PLoS One 2013; 8:e53739. [PMID: 23326495 PMCID: PMC3543261 DOI: 10.1371/journal.pone.0053739] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 12/03/2012] [Indexed: 11/19/2022] Open
Abstract
Desmosomes provide intercellular adhesive strength required for integrity of epithelial and some non-epithelial tissues. Within the epidermis, the cadherin-type adhesion molecules desmoglein (Dsg) 1-4 and desmocollin (Dsc) 1-3 build the adhesive core of desmosomes. In keratinocytes, several isoforms of these proteins are co-expressed. However, the contribution of specific isoforms to overall cell cohesion is unclear. Therefore, in this study we investigated the roles of Dsg2 and Dsg3, the latter of which is known to be essential for keratinocyte adhesion based on its autoantibody-induced loss of function in the autoimmune blistering skin disease pemphigus vulgaris (PV). The pathogenic PV antibody AK23, targeting the Dsg3 adhesive domain, led to profound loss of cell cohesion in human keratinocytes as revealed by the dispase-based dissociation assays. In contrast, an antibody against Dsg2 had no effect on cell cohesion although the Dsg2 antibody was demonstrated to interfere with Dsg2 transinteraction by single molecule atomic force microscopy and was effective to reduce cell cohesion in intestinal epithelial Caco-2 cells which express Dsg2 as the only Dsg isoform. To substantiate these findings, siRNA-mediated silencing of Dsg2 or Dsg3 was performed in keratinocytes. In contrast to Dsg3-depleted cells, Dsg2 knockdown reduced cell cohesion only under conditions of increased shear. These experiments indicate that specific desmosomal cadherins contribute differently to keratinocyte cohesion and that Dsg2 compared to Dsg3 is less important in this context.
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75
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Kowalczyk AP, Green KJ. Structure, function, and regulation of desmosomes. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 116:95-118. [PMID: 23481192 DOI: 10.1016/b978-0-12-394311-8.00005-4] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Desmosomes are adhesive intercellular junctions that mechanically integrate adjacent cells by coupling adhesive interactions mediated by desmosomal cadherins to the intermediate filament cytoskeletal network. Desmosomal cadherins are connected to intermediate filaments by densely clustered cytoplasmic plaque proteins comprising members of the armadillo gene family, including plakoglobin and plakophilins, and members of the plakin family of cytolinkers, such as desmoplakin. The importance of desmosomes in tissue integrity is highlighted by human diseases caused by mutations in desmosomal genes, autoantibody attack of desmosomal cadherins, and bacterial toxins that selectively target desmosomal cadherins. In addition to reviewing the well-known roles of desmosomal proteins in tissue integrity, this chapter also highlights the growing appreciation for how desmosomal proteins are integrated with cell signaling pathways to contribute to vertebrate tissue organization and differentiation.
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Affiliation(s)
- Andrew P Kowalczyk
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
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76
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Insights into the role of cell-cell junctions in physiology and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 306:187-221. [PMID: 24016526 DOI: 10.1016/b978-0-12-407694-5.00005-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Contacting cells establish different classes of intricate structures at the cell-cell junctions. These structures are of increasing research interest as they regulate a broad variety of processes in development and disease. Further, in vitro studies are revealing that various cell-cell interaction proteins are involved not only in cell-cell processes but also in many additional aspects of physiology, such as migration and apoptosis. This chapter reviews the basic classification of cell-cell junctional structures and some of their representative proteins. Their roles in development and disease are briefly outlined, followed by a section on contemporary methods for probing cell-cell interactions and some recent developments. This chapter concludes with a few suggestions for potential research directions to further develop this promising area of study.
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Chen J, Nekrasova OE, Patel DM, Klessner JL, Godsel LM, Koetsier JL, Amargo EV, Desai BV, Green KJ. The C-terminal unique region of desmoglein 2 inhibits its internalization via tail-tail interactions. ACTA ACUST UNITED AC 2012; 199:699-711. [PMID: 23128240 PMCID: PMC3494854 DOI: 10.1083/jcb.201202105] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tail–tail interactions of desmoglein 2, promoted by its C-terminal unique region, inhibit its internalization, stabilizing it at the cell surface and promoting intercellular adhesion. Desmosomal cadherins, desmogleins (Dsgs) and desmocollins, make up the adhesive core of intercellular junctions called desmosomes. A critical determinant of epithelial adhesive strength is the level and organization of desmosomal cadherins on the cell surface. The Dsg subclass of desmosomal cadherins contains a C-terminal unique region (Dsg unique region [DUR]) with unknown function. In this paper, we show that the DUR of Dsg2 stabilized Dsg2 at the cell surface by inhibiting its internalization and promoted strong intercellular adhesion. DUR also facilitated Dsg tail–tail interactions. Forced dimerization of a Dsg2 tail lacking the DUR led to decreased internalization, supporting the conclusion that these two functions of the DUR are mechanistically linked. We also show that a Dsg2 mutant, V977fsX1006, identified in arrhythmogenic right ventricular cardiomyopathy patients, led to a loss of Dsg2 tail self-association and underwent rapid endocytosis in cardiac muscle cells. Our observations illustrate a new mechanism desmosomal cadherins use to control their surface levels, a key factor in determining their adhesion and signaling roles.
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Affiliation(s)
- Jing Chen
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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78
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79
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Abstract
Desmosomes are intercellular adhesive junctions that are particularly prominent in tissues experiencing mechanical stress, such as the heart and epidermis. Whereas the related adherens junction links actin to calcium-dependent adhesion molecules known as classical cadherins, desmosomes link intermediate filaments (IF) to the related subfamily of desmosomal cadherins. By tethering these stress-bearing cytoskeletal filaments to the plasma membrane, desmosomes serve as integrators of the IF cytoskeleton throughout a tissue. Recent evidence suggests that IF attachment in turn strengthens desmosomal adhesion. This collaborative arrangement results in formation of a supracellular network, which is critical for imparting mechanical integrity to tissues. Diseases and animal models targeting desmosomal components highlight the importance of desmosomes in development and tissue integrity, while the downregulation of individual protein components in cancer metastasis and wound healing suggests their importance in cell homeostasis. This chapter will provide an update on desmosome composition, function, and regulation, and will also discuss recent work which raises the possibility that desmosome proteins do more than play a structural role in tissues where they reside.
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80
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Kimura TE, Merritt AJ, Lock FR, Eckert JJ, Fleming TP, Garrod DR. Desmosomal adhesiveness is developmentally regulated in the mouse embryo and modulated during trophectoderm migration. Dev Biol 2012; 369:286-97. [PMID: 22819675 DOI: 10.1016/j.ydbio.2012.06.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 06/28/2012] [Accepted: 06/29/2012] [Indexed: 12/16/2022]
Abstract
During embryonic development tissues remain malleable to participate in morphogenetic movements but on completion of morphogenesis they must acquire the toughness essential for independent adult life. Desmosomes are cell-cell junctions that maintain tissue integrity especially where resistance to mechanical stress is required. Desmosomes in adult tissues are termed hyper-adhesive because they adhere strongly and are experimentally resistant to extracellular calcium chelation. Wounding results in weakening of desmosomal adhesion to a calcium-dependent state, presumably to facilitate cell migration and wound closure. Since desmosomes appear early in mouse tissue development we hypothesised that initial weak adhesion would be followed by acquisition of hyper-adhesion, the opposite of what happens on wounding. We show that epidermal desmosomes are calcium-dependent until embryonic day 12 (E12) and become hyper-adhesive by E14. Similarly, trophectodermal desmosomes change from calcium-dependence to hyper-adhesiveness as blastocyst development proceeds from E3 to E4.5. In both, development of hyper-adhesion is accompanied by the appearance of a midline between the plasma membranes supporting previous evidence that hyper-adhesiveness depends on the organised arrangement of desmosomal cadherins. By contrast, adherens junctions remain calcium-dependent throughout but tight junctions become calcium-independent as desmosomes mature. Using protein kinase C (PKC) activation and PKCα-/- mice, we provide evidence suggesting that conventional PKC isoforms are involved in developmental progression to hyper-adhesiveness. We demonstrate that modulation of desmosomal adhesion by PKC can regulate migration of trophectoderm. It appears that tissue stabilisation is one of several roles played by desmosomes in animal development.
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81
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Abstract
Much of the original research on desmosomes and their biochemical components was through analysis of skin and mucous membranes. The identification of desmogleins 1 and 3, desmosomal adhesion glycoproteins, as targets in pemphigus, a fatal autoimmune blistering disease of the skin and mucous membranes, provided the first link between desmosomes, desmogleins, and human diseases. The clinical and histological similarities of staphylococcal scalded skin syndrome or bullous impetigo and pemphigus foliaceus led us to identify desmoglein 1 as the proteolytic target of staphylococcal exfoliative toxins. Genetic analysis of striate palmoplantar keratoderma and hypotrichosis identified their responsible genes as desmogleins 1 and 4, respectively. More recently, these fundamental findings in cutaneous biology were extended beyond the skin. Desmoglein 2, which is expressed earliest among the four isoforms of desmoglein in development and found in all desmosome-bearing epithelial cells, was found to be mutated in arrythmogenic right ventricular cardiomyopathy and has also been identified as a receptor for a subset of adenoviruses that cause respiratory and urinary tract infections. The story of desmoglein research illuminates how dermatological research, originally focused on one skin disease, pemphigus, has contributed to understanding the biology and pathophysiology of many seemingly unrelated tissues and diseases.
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Affiliation(s)
- Masayuki Amagai
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
| | - John R. Stanley
- Department of Dermatology, University of Pennsylvania, Philadelphia, PA, USA
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82
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Desmosomal cadherins in zebrafish epiboly and gastrulation. BMC DEVELOPMENTAL BIOLOGY 2012; 12:1. [PMID: 22235774 PMCID: PMC3268089 DOI: 10.1186/1471-213x-12-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 01/11/2012] [Indexed: 01/30/2023]
Abstract
Background The desmosomal cadherins (DCs), desmocollin (Dsc) and desmoglein (Dsg), are the adhesion molecules of desmosomes, intercellular adhesive junctions of epithelia and cardiac muscle. Both the DCs and desmosomes have demonstrably essential roles in mammalian development. In order to initiate their study in a more tractable developmental system we have characterised zebrafish DCs and examined their roles in early zebrafish development. Results We find that zebrafish possess one Dsc, the orthologue of mammalian Dsc1, which we designate zfDsc. Unlike mammalian Dscs, zfDsc exists only as the "a" form since it lacks the alternatively-spliced mini-exon that shortens the cytoplasmic domain to produce the "b" form. Zebrafish possess two Dsgs, designated zfDsgα and zfDsgβ, orthologues of mammalian Dsg2. They show 43.8% amino acid identity and the α form has a 43 amino acid glycine-rich sequence of unknown function in its extracellular domain. Both zfDsc and zfDsgα were present as maternal and zygotic transcripts whereas zfDsgβ was first expressed from 8 hours post-fertilisation (hpf). All three transcripts were present throughout subsequent stages of development. Morpholino knockdown of both zfDsc and zfDsgα expression produced similar defects in epiboly, axis elongation and somite formation, associated with abnormal desmosomes or reduced desmosome numbers. Conclusions These results demonstrate an important role for DCs and desmosomes in the early morphogenesis of the zebrafish embryo, provide a basis for more detailed analysis of their role and raise interesting questions relating to the evolution and functional significance of DC isoforms.
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83
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Gehmlich K, Syrris P, Reimann M, Asimaki A, Ehler E, Evans A, Quarta G, Pantazis A, Saffitz JE, McKenna WJ. Molecular changes in the heart of a severe case of arrhythmogenic right ventricular cardiomyopathy caused by a desmoglein-2 null allele. Cardiovasc Pathol 2011; 21:275-82. [PMID: 22036071 DOI: 10.1016/j.carpath.2011.09.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 07/29/2011] [Accepted: 09/16/2011] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder caused by mutations in desmosomal genes. It is often associated with life-threatening arrhythmias. Some affected individuals develop progressive heart failure and may require cardiac transplantation. METHODS The explanted heart of a young adult with end-stage heart failure due to a null allele in desmoglein-2 was studied at macroscopic, microscopic, and molecular level. Myocardial samples were probed for junctional localization of desmosomal components and the gap junction protein connexin43 by immunohistochemical staining. In addition, the protein content of desmosomal and adherens junction markers as well as connexin43 was assessed by Western blotting. RESULTS Histological analysis confirmed ARVC. Despite the loss of specific immunoreactive signal for desmosomal components at the cardiac intercalated disks (shown for plakoglobin, desmoplakin, and plakophilin-2), these proteins could be detected by Western blotting. Only for desmoglein-2, desmocollin-2, and plakoglobin were reduced protein levels observed. Adherens junction proteins were not affected. Lower phosphorylation levels were observed for connexin43; however, localization of the gap junction protein displayed regional differences. At the molecular level, disease progression was more severe in the right ventricle compared to the left ventricle. CONCLUSION Our data suggest that, in the ARVC heart, plakoglobin is mainly redistributed from the junctions to other cellular pools and that protein degradation only plays a secondary role. Homogenous changes in the phosphorylation status of connexin43 were observed in multiple ARVC samples, suggesting that this might be a general feature of the disease.
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Affiliation(s)
- Katja Gehmlich
- Institute of Cardiovascular Science and The Heart Hospital, University College London, United Kingdom.
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Pilichou K, Bezzina CR, Thiene G, Basso C. Arrhythmogenic cardiomyopathy: transgenic animal models provide novel insights into disease pathobiology. ACTA ACUST UNITED AC 2011; 4:318-26. [PMID: 21673311 DOI: 10.1161/circgenetics.110.959031] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Kalliopi Pilichou
- Department of Medical Diagnostic Sciences and Special Therapies, University of Padua, Padua, Italy
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85
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Abstract
Desmoglein-2 (Dsg2) is a desmosomal cadherin that is aberrantly expressed in human skin carcinomas. In addition to its well-known role in mediating intercellular desmosomal adhesion, Dsg2 regulates mitogenic signaling that may promote cancer development and progression. However, the mechanisms by which Dsg2 activates these signaling pathways and the relative contribution of its signaling and adhesion functions in tumor progression are poorly understood. In this study we show that Dsg2 associates with caveolin-1 (Cav-1), the major protein of specialized membrane microdomains called caveolae, which functions in both membrane protein turnover and intracellular signaling. Sequence analysis revealed that Dsg2 contains a putative Cav-1-binding motif. A permeable competing peptide resembling the Cav-1 scaffolding domain bound to Dsg2, disrupted normal Dsg2 staining and interfered with the integrity of epithelial sheets in vitro. Additionally, we observed that Dsg2 is proteolytically processed; resulting in a 95-kDa ectodomain shed product and a 65-kDa membrane-spanning fragment, the latter of which localizes to lipid rafts along with full-length Dsg2. Disruption of lipid rafts shifted Dsg2 to the non-raft fractions, leading to the accumulation of these proteins. Interestingly, Dsg2 proteolytic products are elevated in vivo in skin tumors from transgenic mice overexpressing Dsg2. Collectively, these data are consistent with the possibility that accumulation of truncated Dsg2 protein interferes with desmosome assembly and/or maintenance to disrupt cell-cell adhesion. Furthermore, the association of Dsg2 with Cav-1 may provide a mechanism for regulating mitogenic signaling and modulating the cell-surface presentation of an important adhesion molecule, both of which could contribute to malignant transformation and tumor progression.
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86
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Abstract
Adherens junctions, which are intercellular adhesive complexes that are crucial for maintaining epithelial homeostasis, are downregulated in many cancers to promote tumour progression. However, the role of desmosomes - adhesion complexes that are related to adherens junctions - in carcinogenesis has remained elusive. Recent studies using mouse genetic approaches have uncovered a role for desmosomes in tumour suppression, demonstrating that desmosome downregulation occurs before that of adherens junctions to drive tumour development and early invasion, suggesting a two-step model of adhesion dysfunction in cancer progression.
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Affiliation(s)
- Rachel L Dusek
- Department of Radiation Oncology and Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
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87
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Krusche CA, Holthöfer B, Hofe V, van de Sandt AM, Eshkind L, Bockamp E, Merx MW, Kant S, Windoffer R, Leube RE. Desmoglein 2 mutant mice develop cardiac fibrosis and dilation. Basic Res Cardiol 2011; 106:617-33. [PMID: 21455723 PMCID: PMC3105238 DOI: 10.1007/s00395-011-0175-y] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 03/09/2011] [Accepted: 03/21/2011] [Indexed: 12/13/2022]
Abstract
Desmosomes are cell–cell adhesion sites and part of the intercalated discs, which couple adjacent cardiomyocytes. The connection is formed by the extracellular domains of desmosomal cadherins that are also linked to the cytoskeleton on the cytoplasmic side. To examine the contribution of the desmosomal cadherin desmoglein 2 to cardiomyocyte adhesion and cardiac function, mutant mice were prepared lacking a part of the extracellular adhesive domain of desmoglein 2. Most live born mutant mice presented normal overall cardiac morphology at 2 weeks. Some animals, however, displayed extensive fibrotic lesions. Later on, mutants developed ventricular dilation leading to cardiac insufficiency and eventually premature death. Upon histological examination, cardiomyocyte death by calcifying necrosis and replacement by fibrous tissue were observed. Fibrotic lesions were highly proliferative in 2-week-old mutants, whereas the fibrotic lesions of older mutants showed little proliferation indicating the completion of local muscle replacement by scar tissue. Disease progression correlated with increased mRNA expression of c-myc, ANF, BNF, CTGF and GDF15, which are markers for cardiac stress, remodeling and heart failure. Taken together, the desmoglein 2-mutant mice display features of dilative cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy, an inherited human heart disease with pronounced fibrosis and ventricular arrhythmias that has been linked to mutations in desmosomal proteins including desmoglein 2.
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Affiliation(s)
- Claudia A. Krusche
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Bastian Holthöfer
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Valérie Hofe
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Annette M. van de Sandt
- Division of Cardiology, Angiology and Pneumology, Department of Medicine, University Hospital Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Leonid Eshkind
- Institute for Toxicology, Medical Centre of the Johannes Gutenberg-University Mainz, Obere Zahlbacher Str. 67, 55131 Mainz, Germany
| | - Ernesto Bockamp
- Institute for Toxicology, Medical Centre of the Johannes Gutenberg-University Mainz, Obere Zahlbacher Str. 67, 55131 Mainz, Germany
| | - Marc W. Merx
- Division of Cardiology, Angiology and Pneumology, Department of Medicine, University Hospital Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Sebastian Kant
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Reinhard Windoffer
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Rudolf E. Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
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Chang EH, Pezzulo AA, Zabner J. Do cell junction protein mutations cause an airway phenotype in mice or humans? Am J Respir Cell Mol Biol 2011; 45:202-20. [PMID: 21297078 DOI: 10.1165/rcmb.2010-0498tr] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Cell junction proteins connect epithelial cells to each other and to the basement membrane. Genetic mutations of these proteins can cause alterations in some epithelia leading to varied phenotypes such as deafness, renal disease, skin disorders, and cancer. This review examines if genetic mutations in these proteins affect the function of lung airway epithelia. We review cell junction proteins with examples of disease mutation phenotypes in humans and in mouse knockout models. We also review which of these genes are expressed in airway epithelium by microarray expression profiling and immunocytochemistry. Last, we present a comprehensive literature review to find the lung phenotype when cell junction and adhesion genes are mutated or subject to targeted deletion. We found that in murine models, targeted deletion of cell junction and adhesion genes rarely result in a lung phenotype. Moreover, mutations in these genes in humans have no obvious lung phenotype. Our research suggests that simply because a cell junction or adhesion protein is expressed in an organ does not imply that it will exhibit a drastic phenotype when mutated. One explanation is that because a functioning lung is critical to survival, redundancy in the system is expected. Therefore mutations in a single gene might be compensated by a related function of a similar gene product. Further studies in human and animal models will help us understand the overlap in the function of cell junction gene products. Finally, it is possible that the human lung phenotype is subtle and has not yet been described.
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Affiliation(s)
- Eugene H Chang
- Department of Otolaryngology–Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, USA
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89
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Lie PPY, Cheng CY, Mruk DD. The biology of the desmosome-like junction a versatile anchoring junction and signal transducer in the seminiferous epithelium. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 286:223-69. [PMID: 21199783 PMCID: PMC4381909 DOI: 10.1016/b978-0-12-385859-7.00005-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Mammalian spermatogenesis, a complex process that involves the movement of developing germ cells across the seminiferous epithelium, entails extensive restructuring of Sertoli-Sertoli and Sertoli-germ cell junctions. Presently, it is not entirely clear how zygotene spermatocytes gain entry into the adluminal compartment of the seminiferous epithelium, which is sealed off from the systemic circulation by the Sertoli cell component of the blood-testis barrier, without compromising barrier integrity. To begin to address this question, it is critical that we first have a good understanding of the biology and the regulation of different types of Sertoli-Sertoli and Sertoli-germ cell junctions in the testis. Supported by recent studies in the field, we discuss how crosstalk between different types of junctions contributes to their restructuring during germ cell movement across the blood-testis barrier. We place special emphasis on the emerging role of desmosome-like junctions as signal transducers during germ cell movement across the seminiferous epithelium.
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Affiliation(s)
- Pearl P Y Lie
- Population Council, Center for Biomedical Research, New York, New York, USA
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90
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Teh MT, Parkinson EK, Thurlow JK, Liu F, Fortune F, Wan H. A molecular study of desmosomes identifies a desmoglein isoform switch in head and neck squamous cell carcinoma. J Oral Pathol Med 2010; 40:67-76. [PMID: 20923451 DOI: 10.1111/j.1600-0714.2010.00951.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Desmosomes, the intercellular junctions that confer strong adhesion between epithelial cells, are frequently altered in malignancy. However, a comprehensive analysis of these structures has not been carried out in oral neoplasia. Oral squamous cell carcinomas (SCCs) and pre-malignant dysplasia can be sub-classified according to their in vitro replicative lifespan, where the immortal dysplasia (ID) and carcinoma (IC) subsets have p16(ink4a) and p53 dysfunction, telomerase deregulation and genetic instability and the mortal subset (MD and MC) do not. We found that the desmosomal proteins exhibit a distinct expression pattern in oral mucosa when compared with epidermis in vivo. Microarray data from a large panel of lines revealed that the transcript levels of DSG3, DSC2/3, DP, PG and PKP1 were reduced in ID and IC. Interestingly, DSG2 was up-regulated in MC. Reduction of DSG3 and up-regulation of DSG2 were found in two independent microarray datasets. Significantly, we demonstrated that reduction of DSG3 and up-regulation of DSG2 was reversible in vitro by using RNAi-mediated knockdown of DSG2 in IC cells. The remaining desmosomal proteins were largely disrupted or internalized and associated with retraction of keratin intermediate filaments in oral SCC lines. These findings suggest dysfunction and loss of desmosomal components are common events in the immortal class of oral SCC and that these events may precede overt malignancy.
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Affiliation(s)
- Muy-Teck Teh
- Queen Mary University of London, Barts & The London, School of Medicine and Dentistry, Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, London, UK
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91
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The Misregulation of Cell Adhesion Components during Tumorigenesis: Overview and Commentary. JOURNAL OF ONCOLOGY 2010; 2010. [PMID: 20953359 PMCID: PMC2952821 DOI: 10.1155/2010/174715] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 08/23/2010] [Accepted: 09/10/2010] [Indexed: 12/18/2022]
Abstract
Cell adhesion complexes facilitate attachment between cells or the binding of cells to the extracellular matrix. The regulation of cell adhesion is an important step in embryonic development and contributes to tissue homeostasis allowing processes such as differentiation and cell migration. Many mechanisms of cancer progression are reminiscent of embryonic development, for example, epithelial-mesenchymal transition, and involve the disruption of cell adhesion and expression changes in components of cell adhesion structures. Tight junctions, adherens junctions, desmosomes, and focal adhesion besides their roles in cell-cell or cell-matrix interaction also possess cell signaling function. Perturbations of such signaling pathways can lead to cancer. This article gives an overview of the common structures of cell adhesion and summarizes the impact of their loss on cancer development and progression with articles highlighted from the present issue.
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92
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Abstract
The 6-billion human population provides a vast reservoir of mutations, which, in addition to the opportunity of detecting very subtle defects, including specific cognitive dysfunctions as well as late appearing disorders, offers a unique background in which to investigate the roles of cell-cell adhesion proteins. Here we focus on inherited human disorders involving members of the cadherin superfamily. Most of the advances concern monogenic disorders. Yet, with the development of single nucleotide polymorphism (SNP) association studies, cadherin genes are emerging as susceptibility genes in multifactorial disorders. Various skin and heart disorders revealed the critical role played by desmosomal cadherins in epidermis, hairs, and myocardium, which experience high mechanical stress. Of particular interest in that respect is the study of Usher syndrome type 1 (USH1), a hereditary syndromic form of deafness. Studies of USH1 brought to light the crucial role of transient fibrous links formed by cadherin 23 and protocadherin 15 in the cohesion of the developing hair bundle, the mechanoreceptive structure of the auditory sensory cells, as well as the involvement of these cadherins in the formation of the tip-link, a key component of the mechano-electrical transduction machinery. Finally, in line with the well-established role of cadherins in synaptic formation, maintenance, strength, and plasticity, a growing number of cadherin family members, especially protocadherins, have been found to be involved in neuropsychiatric disorders.
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Affiliation(s)
- Aziz El-Amraoui
- Institut Pasteur, Unité de Génétique et Physiologie de l'Audition, 25 Rue du Dr Roux, 75015 Paris, France.
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93
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Abstract
Desmosomes are intercellular junctions that tether intermediate filaments to the plasma membrane. Desmogleins and desmocollins, members of the cadherin superfamily, mediate adhesion at desmosomes. Cytoplasmic components of the desmosome associate with the desmosomal cadherin tails through a series of protein interactions, which serve to recruit intermediate filaments to sites of desmosome assembly. These desmosomal plaque components include plakoglobin and the plakophilins, members of the armadillo gene family. Linkage to the cytoskeleton is mediated by the intermediate filament binding protein, desmoplakin, which associates with both plakoglobin and plakophilins. Although desmosomes are critical for maintaining stable cell-cell adhesion, emerging evidence indicates that they are also dynamic structures that contribute to cellular processes beyond that of cell adhesion. This article outlines the structure and function of the major desmosomal proteins, and explores the contributions of this protein complex to tissue architecture and morphogenesis.
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Affiliation(s)
- Emmanuella Delva
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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94
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Abstract
Desmosomes are intercellular junctions whose primary function is strong intercellular adhesion, known as hyperadhesion. In the present review, we discuss how their structure appears to support this function as well as how they are assembled and down-regulated. Desmosomal components also have signalling functions that are important in tissue development and remodelling. Their adhesive and signalling functions are both compromised in genetic and autoimmune diseases that affect the heart, skin and mucous membranes. We conclude that much work is required on structure–function relationships within desmosomes in vivo and on how they participate in signalling processes to enhance our knowledge of tissue homoeostasis and human disease.
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95
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Exploring the Nature of Desmosomal Cadherin Associations in 3D. Dermatol Res Pract 2010; 2010:930401. [PMID: 20672011 PMCID: PMC2905946 DOI: 10.1155/2010/930401] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 02/17/2010] [Accepted: 04/16/2010] [Indexed: 12/01/2022] Open
Abstract
Desmosomes are a complex assembly of protein molecules that mediate adhesion between adjacent cells. Desmosome composition is well established and spatial relationships between components have been identified. Intercellular cell-cell adhesion is created by the interaction of extracellular domains of desmosomal cadherins, namely, desmocollins and desmogleins. High-resolution methods have provided insight into the structural interactions between cadherins. However, there is a lack of understanding about the architecture of the intact desmosomes and the physical principles behind their adhesive strength are unclear. Electron Tomography (ET) studies have offered three-dimensional visual data of desmosomal cadherin associations at molecular resolution. This review discusses the merits of two cadherin association models represented using ET. We discuss the possible role of sample preparation on the structural differences seen between models and the possibility of adaptive changes in the structure as a direct consequence of mechanical stress and stratification.
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96
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Biazik JM, Thompson MB, Murphy CR. Desmosomes in the uterine epithelium of noninvasive skink placentae. Anat Rec (Hoboken) 2010; 293:502-12. [PMID: 20169564 DOI: 10.1002/ar.21093] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Australian species of viviparous skinks have noninvasive epitheliochorial placentation where there is no breeching or interruption of the uterine epithelial cell barrier. This is contrary to some African and South American species of skinks which exhibit invading chorionic cells and a localized endotheliochorial placenta. The desmosomes, which maintain the adhesive properties of the junctional complex between uterine epithelial cells, were found to decrease as gestation progressed in the uterus of two highly placentotrophic Australian skinks, but no changes in desmosomal numbers were present in the uterus of two Australian oviparous skinks or viviparous skinks with a simple placenta. In mammals, desmosomes decrease in the uterine epithelium of species with invasive hemochorial placentation, where less chemical and mechanical adhesion between cells assists the invading trophoblast at the time of implantation. However, Australian viviparous skinks do not have an invasive trophoblast; yet, similarities in decreasing lateral cellular adhesion exist in the uterus of both invasive and noninvasive placental types. This similarity in cellular mechanisms suggests a conservation of plasma membrane changes across placentation irrespective of reptilian or mammalian origin.
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Affiliation(s)
- Joanna M Biazik
- Bosch Institute, The University of Sydney, New South Wales, Australia.
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97
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Schlegel N, Meir M, Heupel WM, Holthöfer B, Leube RE, Waschke J. Desmoglein 2-mediated adhesion is required for intestinal epithelial barrier integrity. Am J Physiol Gastrointest Liver Physiol 2010; 298:G774-83. [PMID: 20224006 DOI: 10.1152/ajpgi.00239.2009] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The integrity of intercellular junctions that form the "terminal bar" in intestinal epithelium is crucial for sealing the intestinal barrier. Whereas specific roles of tight and adherens junctions are well known, the contribution of desmosomal adhesion for maintaining the intestinal epithelial barrier has not been specifically addressed. For the present study, we generated a desmoglein 2 antibody directed against the extracellular domain (Dsg2 ED) to test whether impaired Dsg2-mediated adhesion affects intestinal epithelial barrier functions in vitro. This antibody was able to specifically block Dsg2 interaction in cell-free atomic-force microscopy experiments. For in vitro studies of the intestinal barrier we used Caco2 cells following differentiation into tight enterocyte-like epithelial monolayers. Application of Dsg2 ED to Caco2 monolayers resulted in increased cell dissociation compared with controls in a dispase-based enterocyte dissociation assay. Under similar conditions, Dsg2 antibody significantly decreased transepithelial electrical resistance and increased FITC-dextran flux, indicating that Dsg2 interaction is critically involved in the maintenance of epithelial intestinal barrier functions. As revealed by immunostaining, this was due to Dsg2 ED antibody-induced rupture of tight junctions because tight junction proteins claudins 1, 4, and 5, occludin, and tight junction-associated protein zonula occludens-1 were partially removed from cell borders by Dsg2 ED treatment. Similar results were obtained by application of a commercial monoclonal antibody directed against the ED of Dsg2. Antibody-induced effects were blocked by absorption experiments using Dsg2-Fc-coated beads. Our data indicate that Dsg2-mediated adhesion affects tight junction integrity and is required to maintain intestinal epithelial barrier properties.
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Affiliation(s)
- Nicolas Schlegel
- Inst. of Anatomy and Cell Biology, University of Würzburg, Germany
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98
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von Kopylow K, Kirchhoff C, Jezek D, Schulze W, Feig C, Primig M, Steinkraus V, Spiess AN. Screening for biomarkers of spermatogonia within the human testis: a whole genome approach. Hum Reprod 2010; 25:1104-12. [DOI: 10.1093/humrep/deq053] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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100
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Singh H, Aplin JD. Adhesion molecules in endometrial epithelium: tissue integrity and embryo implantation. J Anat 2009; 215:3-13. [PMID: 19453302 PMCID: PMC2714633 DOI: 10.1111/j.1469-7580.2008.01034.x] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2008] [Indexed: 12/16/2022] Open
Abstract
Cell adhesion in endometrial epithelium is regulated to maintain the continuity and protectiveness of the luminal covering cell layer while permitting interstitial implantation of the embryo during a restricted period of about 4 days. Many apparently normal embryos fail to implant, and epithelial-embryo adhesion remains a poorly understood phenomenon. After menstruation, epithelial regeneration occurs by epiboly from the basal residues of glands, an activity that requires migration on extracellular matrix as well as cell-cell cohesion. Here we review current knowledge of adhesion molecules in the epithelium.
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Affiliation(s)
- Harmeet Singh
- Maternal and Fetal Health Research Group, University of Manchester, Manchester, UK
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