1
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Hijazi N, Shi Z, Rockey DC. Paxillin regulates liver fibrosis via actin polymerization and ERK activation in hepatic stellate cells. J Cell Sci 2023; 136:jcs261122. [PMID: 37667902 PMCID: PMC10560551 DOI: 10.1242/jcs.261122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/15/2023] [Indexed: 09/06/2023] Open
Abstract
Liver injury leads to fibrosis and cirrhosis. The primary mechanism underlying the fibrogenic response is the activation of hepatic stellate cells (HSCs), which are 'quiescent' in normal liver but become 'activated' after injury by transdifferentiating into extracellular matrix (ECM)-secreting myofibroblasts. Given that integrins are important in HSC activation and fibrogenesis, we hypothesized that paxillin, a key downstream effector in integrin signaling, might be critical in the fibrosis pathway. Using a cell-culture-based model of HSC activation and in vivo models of liver injury, we found that paxillin is upregulated in activated HSCs and fibrotic livers. Overexpression of paxillin (both in vitro and in vivo) led to increased ECM protein expression, and depletion of paxillin in a novel conditional mouse injury model reduced fibrosis. The mechanism by which paxillin mediated this effect appeared to be through the actin cytoskeleton, which signals to the ERK pathway and induces ECM protein production. These data highlight a novel role for paxillin in HSC biology and fibrosis.
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Affiliation(s)
- Nour Hijazi
- Digestive Disease Research Center Core, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Zengdun Shi
- Digestive Disease Research Center Core, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Don C. Rockey
- Digestive Disease Research Center Core, Medical University of South Carolina, Charleston, SC 29425, USA
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2
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Kaplan L, Drexler C, Pfaller AM, Brenna S, Wunderlich KA, Dimitracopoulos A, Merl-Pham J, Perez MT, Schlötzer-Schrehardt U, Enzmann V, Samardzija M, Puig B, Fuchs P, Franze K, Hauck SM, Grosche A. Retinal regions shape human and murine Müller cell proteome profile and functionality. Glia 2023; 71:391-414. [PMID: 36334068 DOI: 10.1002/glia.24283] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 09/29/2022] [Accepted: 10/07/2022] [Indexed: 11/08/2022]
Abstract
The human macula is a highly specialized retinal region with pit-like morphology and rich in cones. How Müller cells, the principal glial cell type in the retina, are adapted to this environment is still poorly understood. We compared proteomic data from cone- and rod-rich retinae from human and mice and identified different expression profiles of cone- and rod-associated Müller cells that converged on pathways representing extracellular matrix and cell adhesion. In particular, epiplakin (EPPK1), which is thought to play a role in intermediate filament organization, was highly expressed in macular Müller cells. Furthermore, EPPK1 knockout in a human Müller cell-derived cell line led to a decrease in traction forces as well as to changes in cell size, shape, and filopodia characteristics. We here identified EPPK1 as a central molecular player in the region-specific architecture of the human retina, which likely enables specific functions under the immense mechanical loads in vivo.
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Affiliation(s)
- Lew Kaplan
- Department of Physiological Genomics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Corinne Drexler
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria.,Vienna Biocenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Anna M Pfaller
- Department of Physiological Genomics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Santra Brenna
- Neurology Department, Experimental Research in Stroke and Inflammation (ERSI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kirsten A Wunderlich
- Department of Physiological Genomics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Andrea Dimitracopoulos
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Juliane Merl-Pham
- Research Unit Protein Science and Metabolomics and Proteomics Core, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Maria-Theresa Perez
- Department of Clinical Sciences, Division of Ophthalmology, Lund University, Lund, Sweden.,NanoLund, Nanometer Structure Consortium, Lund University, Lund, Sweden
| | | | - Volker Enzmann
- Department of Ophthalmology, Bern University Hospital, Inselspital, University of Bern, Bern, Switzerland.,Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Marijana Samardzija
- Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Berta Puig
- Neurology Department, Experimental Research in Stroke and Inflammation (ERSI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Peter Fuchs
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria
| | - Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK.,Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science and Metabolomics and Proteomics Core, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Antje Grosche
- Department of Physiological Genomics, Ludwig-Maximilians-Universität München, Munich, Germany
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3
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Ge L, Huang P, Miao H, Yu H, Wu D, Chen F, Lin Y, Lin Y, Li W, Hua J. The new landscape of differentially expression proteins in placenta tissues of gestational diabetes based on iTRAQ proteomics. Placenta 2023; 131:36-48. [PMID: 36473392 DOI: 10.1016/j.placenta.2022.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 10/26/2022] [Accepted: 11/24/2022] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Gestational diabetes mellitus (GDM) refers to abnormal glucose tolerance that occurs or is firstly diagnosed during pregnancy. GDM is related to various adverse pregnancy outcomes, but GDM pathogeny has not been fully elucidated. Nevertheless, previous studies have observed that many proteins in the placentas of patients with GDM are dysregulated. The present study aimed to establish a novel differentially expressed protein (DEP) landscape of GDM and normal maternal placentas and to explore the possible connection between DEPs and GDM pathogenesis. This study provides new insights into the mechanism of GDM and should make an important contribution to the development of biomarkers. METHODS The morphological characteristics of the placenta were observed on 30 GDM and normal maternal placental tissues stained with haematoxylin and eosin. Isobaric tags for relative and absolute quantitation (iTRAQ) was used in the proteomics screening of the DEPs of the normal and GDM maternal placentas. Bioinformatics analysis was performed on the DEPs, and parallel reaction monitoring (PRM) was performed to verify the DEPs. Finally, the quantitative analysis of iTRAQ and PRM was verified by immunohistochemical assay. RESULTS A total of 68 DEPs in the GDM placenta were identified with iTRAQ proteomics experiment, comprising 21 up-regulated and 47 down-regulated DEPs. Bioinformatics analysis showed that the regulation of transport, catabolic process of non-coding RNA, cytoskeleton and cell binding were the most abundant Gene Ontology terms, and RNA degradation was an important pathway for significant enrichment. Protein-protein interaction network analysis showed that heterogeneous nuclear ribonucleoproteins A2/B1 (HNRNPA2B1), heterogeneous nuclear ribonucleoprotein A/B (HNRNPAB), heterogeneous nuclear ribonucleoprotein L (HNRNPL) and heterogeneous nuclear ribonucleoprotein A3 (HNRNPA3) were the cores of the up-regulated proteins. Band 3 anion transport protein (SLC4A1), spectrin beta chain erythrocytic (SPTB), ankyrin-1 (ANK1), spectrin beta chain non-erythrocytic 2 (SPTBN2), D-3-phosphoglycerate dehydrogenase (PHGDH) and exosome complex component RRP42 (EXOSC7) were the cores of the down-regulated proteins. These proteins are involved in the binding, splicing, processing, transport and degradation of RNA and in the formation and maintenance of the cytoskeleton. PRM verification results showed that seven proteins, namely, epiplakin (EPPK1), cold-inducible RNA-binding protein (CIRBP), HNRNPA2B1, HNRNPAB, HNRNPL, Ras-related protein Rab-21 (RAB21) and Ras-related protein Rab-3B (RAB3B), were up-regulated, whereas SPTB and SLC4A1 were down-regulated. The results of immunohistochemical assay also showed that the expression of five proteins, namely EPPK1, HNRNPA2B1, HNRNPAB, CIRBP and RAB21, were significantly higher in GDM placental tissues (P < 0.01). The GDM placentas showed changes in the morphological evaluation, including poor villous maturation, obvious increase in the number of syncytiotrophoblast nodules, thickening of the wall of dry villous arterioles with lumen stenosis, increased fibrinous exudation and excessive filling of villous interstitial vessels. DISCUSSION Differentially expressed proteins related to a variety of biological processes in the GDM placenta were found. Fourteen proteins, namely, HNRNPA2B1, HNRNPAB, HNRNPL, HNRNPA3, EPPK1, CIRBP, RAB21, RAB3B, SLC4A1, SPTB, ANK1, SPTBN2, PHGDH and EXOSC7, which were differentially expressed in the placenta, may play an important role in regulating the occurrence and development of gestational diabetes through multi-channel and multi-link regulation.
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Affiliation(s)
- Li Ge
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China.
| | - Pingping Huang
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Haiyan Miao
- Department of Obstetrics and Gynecology, The Second People's Hospital Affiliated to Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Honghong Yu
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Dongmei Wu
- Department of Obstetrics and Gynecology, The Second People's Hospital Affiliated to Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Fan Chen
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Yan Lin
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Yuzheng Lin
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Wenfang Li
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Jinghe Hua
- School of Nursing, Fujian University of Traditional Chinese Medicine, Fuzhou, China
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Ratajczyk S, Drexler C, Windoffer R, Leube RE, Fuchs P. A Ca 2+-Mediated Switch of Epiplakin from a Diffuse to Keratin-Bound State Affects Keratin Dynamics. Cells 2022; 11:cells11193077. [PMID: 36231039 PMCID: PMC9563781 DOI: 10.3390/cells11193077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/19/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
Keratins exert important structural but also cytoprotective functions. They have to be adaptable to support cellular homeostasis. Epiplakin (EPPK1) has been shown to decorate keratin filaments in epithelial cells and to play a protective role under stress, but the mechanism is still unclear. Using live-cell imaging of epithelial cells expressing fluorescently tagged EPPK1 and keratin, we report here an unexpected dynamic behavior of EPPK1 upon stress. EPPK1 was diffusely distributed throughout the cytoplasm and not associated with keratin filaments in living cells under standard culture conditions. However, ER-, oxidative and UV-stress, as well as cell fixation, induced a rapid association of EPPK1 with keratin filaments. This re-localization of EPPK1 was reversible and dependent on the elevation of cytoplasmic Ca2+ levels. Moreover, keratin filament association of EPPK1 led to significantly reduced keratin dynamics. Thus, we propose that EPPK1 stabilizes the keratin network in stress conditions, which involve increased cytoplasmic Ca2+.
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Affiliation(s)
- Sonia Ratajczyk
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), A-1030 Vienna, Austria
- Vienna Biocenter PhD Program, A Doctoral School of the University of Vienna and Medical University of Vienna, A-1030 Vienna, Austria
| | - Corinne Drexler
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), A-1030 Vienna, Austria
- Vienna Biocenter PhD Program, A Doctoral School of the University of Vienna and Medical University of Vienna, A-1030 Vienna, Austria
| | - 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
| | - Peter Fuchs
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), A-1030 Vienna, Austria
- Correspondence: ; Tel.: +43-1-4277-52855
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5
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Fuchs P, Drexler C, Ratajczyk S, Eckhart L. Comparative genomics reveals evolutionary loss of epiplakin in cetaceans. Sci Rep 2022; 12:1112. [PMID: 35064199 PMCID: PMC8782857 DOI: 10.1038/s41598-022-05087-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 01/06/2022] [Indexed: 12/14/2022] Open
Abstract
The adaptation of vertebrates to different environments was associated with changes in the molecular composition and regulation of epithelia. Whales and dolphins, together forming the clade cetaceans, have lost multiple epithelial keratins during or after their evolutionary transition from life on land to life in water. It is unknown whether the changes in keratins were accompanied by gain or loss of cytoskeletal adapter proteins of the plakin family. Here we investigated whether plakin proteins are conserved in cetaceans and other vertebrates. Comparative analysis of genome sequences showed conservation of dystonin, microtubule actin crosslinking factor 1 (MACF1), plectin, desmoplakin, periplakin and envoplakin in cetaceans. By contrast, EPPK1 (epiplakin) was disrupted by inactivating mutations in all cetaceans investigated. Orthologs of EPPK1 are present in bony and cartilaginous fishes and tetrapods, indicating an evolutionary origin of EPPK1 in a common ancestor of jawed vertebrates (Gnathostomes). In many vertebrates, EPPK1 is flanked by an as-yet uncharacterized gene that encodes protein domains homologous to the carboxy-terminal segment of MACF1. We conclude that epiplakin, unlike other plakins, was lost in cetaceans.
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Affiliation(s)
- Peter Fuchs
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria.
| | - Corinne Drexler
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria
| | - Sonia Ratajczyk
- Max Perutz Labs, Department of Biochemistry and Cell Biology, University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria
| | - Leopold Eckhart
- Skin Biology Laboratory, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
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6
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Castañón MJ, Wiche G. Identifying Plectin Isoform Functions through Animal Models. Cells 2021; 10:cells10092453. [PMID: 34572100 PMCID: PMC8468861 DOI: 10.3390/cells10092453] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/04/2021] [Accepted: 09/14/2021] [Indexed: 12/12/2022] Open
Abstract
Plectin, a high-molecular-weight cytoskeletal linker protein, binds with high affinity to intermediate filaments of all types and connects them to junctional complexes, organelles, and inner membrane systems. In addition, it interacts with actomyosin structures and microtubules. As a multifunctional protein, plectin has been implicated in several multisystemic diseases, the most common of which is epidermolysis bullosa simplex with muscular dystrophy (EBS-MD). A great part of our knowledge about plectin’s functional diversity has been gained through the analysis of a unique collection of transgenic mice that includes a full (null) knockout (KO), several tissue-restricted and isoform-specific KOs, three double KOs, and two knock-in lines. The key molecular features and pathological phenotypes of these mice will be discussed in this review. In summary, the analysis of the different genetic models indicated that a functional plectin is required for the proper function of striated and simple epithelia, cardiac and skeletal muscle, the neuromuscular junction, and the vascular endothelium, recapitulating the symptoms of humans carrying plectin mutations. The plectin-null line showed severe skin and muscle phenotypes reflecting the importance of plectin for hemidesmosome and sarcomere integrity; whereas the ablation of individual isoforms caused a specific phenotype in myofibers, basal keratinocytes, or neurons. Tissue-restricted ablation of plectin rendered the targeted cells less resilient to mechanical stress. Studies based on animal models other than the mouse, such as zebrafish and C. elegans, will be discussed as well.
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Wesley T, Berzins S, Kannourakis G, Ahmed N. The attributes of plakins in cancer and disease: perspectives on ovarian cancer progression, chemoresistance and recurrence. Cell Commun Signal 2021; 19:55. [PMID: 34001250 PMCID: PMC8127266 DOI: 10.1186/s12964-021-00726-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 02/20/2021] [Indexed: 02/06/2023] Open
Abstract
The plakin family of cytoskeletal proteins play an important role in cancer progression yet are under-studied in cancer, especially ovarian cancer. These large cytoskeletal proteins have primary roles in the maintenance of cytoskeletal integrity but are also associated with scaffolds of intermediate filaments and hemidesmosomal adhesion complexes mediating signalling pathways that regulate cellular growth, migration, invasion and differentiation as well as stress response. Abnormalities of plakins, and the closely related spectraplakins, result in diseases of the skin, striated muscle and nervous tissue. Their prevalence in epithelial cells suggests that plakins may play a role in epithelial ovarian cancer progression and recurrence. In this review article, we explore the roles of plakins, particularly plectin, periplakin and envoplakin in disease-states and cancers with emphasis on ovarian cancer. We discuss the potential role the plakin family of proteins play in regulating cancer cell growth, survival, migration, invasion and drug resistance. We highlight potential relationships between plakins, epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) and discuss how interaction of these processes may affect ovarian cancer progression, chemoresistance and ultimately recurrence. We propose that molecular changes in the expression of plakins leads to the transition of benign ovarian tumours to carcinomas, as well as floating cellular aggregates (commonly known as spheroids) in the ascites microenvironment, which may contribute to the sustenance and progression of the disease. In this review, attempts have been made to understand the crucial changes in plakin expression in relation to progression and recurrence of ovarian cancer. Video Abstract
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Affiliation(s)
- Tamsin Wesley
- Fiona Elsey Cancer Research Institute, Ballarat Technology Central Park, Suites 23-26, 106-110 Lydiard Street South, Ballarat, VIC, 3353, Australia.,School of Science, Psychology and Sport, Federation University Australia, Ballarat, VIC, 3010, Australia
| | - Stuart Berzins
- Fiona Elsey Cancer Research Institute, Ballarat Technology Central Park, Suites 23-26, 106-110 Lydiard Street South, Ballarat, VIC, 3353, Australia.,School of Science, Psychology and Sport, Federation University Australia, Ballarat, VIC, 3010, Australia
| | - George Kannourakis
- Fiona Elsey Cancer Research Institute, Ballarat Technology Central Park, Suites 23-26, 106-110 Lydiard Street South, Ballarat, VIC, 3353, Australia.,School of Science, Psychology and Sport, Federation University Australia, Ballarat, VIC, 3010, Australia
| | - Nuzhat Ahmed
- Fiona Elsey Cancer Research Institute, Ballarat Technology Central Park, Suites 23-26, 106-110 Lydiard Street South, Ballarat, VIC, 3353, Australia. .,School of Science, Psychology and Sport, Federation University Australia, Ballarat, VIC, 3010, Australia. .,Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, VIC, 3052, Australia. .,Centre for Reproductive Health, The Hudson Institute of Medical Research and Department of Translational Medicine, Monash University, Melbourne, VIC, 3168, Australia.
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8
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Keratin intermediate filaments in the colon: guardians of epithelial homeostasis. Int J Biochem Cell Biol 2020; 129:105878. [PMID: 33152513 DOI: 10.1016/j.biocel.2020.105878] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/24/2020] [Accepted: 10/29/2020] [Indexed: 12/12/2022]
Abstract
Keratin intermediate filament proteins are major cytoskeletal components of the mammalian simple layered columnar epithelium in the gastrointestinal tract. Human colon crypt epithelial cells express keratins 18, 19 and 20 as the major type I keratins, and keratin 8 as the type II keratin. Keratin expression patterns vary between species, and mouse colonocytes express keratin 7 as a second type II keratin. Colonic keratin patterns change during cell differentiation, such that K20 increases in the more differentiated crypt cells closer to the central lumen. Keratins provide a structural and mechanical scaffold to support cellular stability, integrity and stress protection in this rapidly regenerating tissue. They participate in central colonocyte processes including barrier function, ion transport, differentiation, proliferation and inflammatory signaling. The cell-specific keratin compositions in different epithelial tissues has allowed for the utilization of keratin-based diagnostic methods. Since the keratin expression pattern in tumors often resembles that in the primary tissue, it can be used to recognize metastases of colonic origin. This review focuses on recent findings on the biological functions of mammalian colon epithelial keratins obtained from pivotal in vivo models. We also discuss the diagnostic value of keratins in chronic colonic disease and known keratin alterations in colon pathologies. This review describes the biochemical properties of keratins and their molecular actions in colonic epithelial cells and highlights diagnostic data in colorectal cancer and inflammatory bowel disease patients, which may facilitate the recognition of disease subtypes and the establishment of personal therapies in the future.
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Ye J, Wu Y, Li M, Gong X, Zhong B. Keratin 8 Mutations Were Associated With Susceptibility to Chronic Hepatitis B and Related Progression. J Infect Dis 2020; 221:464-473. [PMID: 31515557 DOI: 10.1093/infdis/jiz467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/10/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Keratin 8 and 18 (K8/K18) are the exclusively expressed keratins intermediate filaments pair in hepatocytes that protect against liver injuries and viral infection. We aimed to explore the genetic link between keratin variants and chronic hepatitis B virus (CHB) infection in a large cohort from a high-epidemic area. METHODS Genomic deoxyribonucleic acid was isolated from patients, and Sanger sequencing was applied to analyze variations in exon regions of K8/18. Biochemical and functional analysis of novel mutations was also performed. RESULTS The 713 participants comprised 173 healthy controls and 540 patients, which covered chronic hepatitis (n = 174), decompensated cirrhosis (n = 192), and primary liver carcinoma (n = 174). The frequency of mutations in K8/18 was significantly higher among patients than among controls (8.15% vs 0.58%, P < .001). Significant differences were found between the chronic hepatitis subgroup and controls in multiple comparisons (6.32% vs 0.58%, P = .006). All 21 missense mutations (3.89%) were detected in the keratin 8 (K8), including 4 novel conserved missense variants (R469C, R469H, A447V, and K483T). Multivariate logistic regression analysis demonstrated a higher risk of acute-on-chronic liver failure (ACLF) and missense variants (odds ratio = 4.38, P = .035). Transfection of these variants caused keratin network disruption in vivo. CONCLUSIONS Novel K8 cytoskeleton-disrupting variants predispose toward ACLF in CHB.
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Affiliation(s)
- Junzhao Ye
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangdong, China
| | - Yanqin Wu
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangdong, China
| | - Minrui Li
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangdong, China
| | - Xiaorong Gong
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangdong, China
| | - Bihui Zhong
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangdong, China
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10
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Mohammed F, Trieber C, Overduin M, Chidgey M. Molecular mechanism of intermediate filament recognition by plakin proteins. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118801. [PMID: 32712070 DOI: 10.1016/j.bbamcr.2020.118801] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/15/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022]
Abstract
The plakin family of cytolinkers interacts with intermediate filaments (IFs) through plakin repeat domain (PRD) and linker modules. Recent structure/function studies have established the molecular basis of envoplakin-PRD and periplakin-linker interactions with vimentin. Both plakin modules share a broad basic groove which recognizes acidic rod elements on IFs, a mechanism that is applicable to other plakin family members. This review postulates a universal IF engagement mechanism that illuminates the specific effects of pathogenic mutations associated with diseases including arrhythmogenic right ventricular cardiomyopathy, and reveals how diverse plakin proteins offer tailored IF tethering to ensure stable, dynamic and regulated cellular structures.
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Affiliation(s)
- Fiyaz Mohammed
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham B15 2TT, UK.
| | - Catharine Trieber
- Department of Biochemistry, Faculty of Medicine and Dentistry, 474 Medical Sciences Building, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
| | - Michael Overduin
- Department of Biochemistry, Faculty of Medicine and Dentistry, 474 Medical Sciences Building, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
| | - Martyn Chidgey
- Institute of Clinical Sciences, University of Birmingham, Birmingham B15 2TT, UK.
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11
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Keratin intermediate filaments: intermediaries of epithelial cell migration. Essays Biochem 2020; 63:521-533. [PMID: 31652439 DOI: 10.1042/ebc20190017] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/13/2019] [Accepted: 09/25/2019] [Indexed: 12/12/2022]
Abstract
Migration of epithelial cells is fundamental to multiple developmental processes, epithelial tissue morphogenesis and maintenance, wound healing and metastasis. While migrating epithelial cells utilize the basic acto-myosin based machinery as do other non-epithelial cells, they are distinguished by their copious keratin intermediate filament (KF) cytoskeleton, which comprises differentially expressed members of two large multigene families and presents highly complex patterns of post-translational modification. We will discuss how the unique mechanophysical and biochemical properties conferred by the different keratin isotypes and their modifications serve as finely tunable modulators of epithelial cell migration. We will furthermore argue that KFs together with their associated desmosomal cell-cell junctions and hemidesmosomal cell-extracellular matrix (ECM) adhesions serve as important counterbalances to the contractile acto-myosin apparatus either allowing and optimizing directed cell migration or preventing it. The differential keratin expression in leaders and followers of collectively migrating epithelial cell sheets provides a compelling example of isotype-specific keratin functions. Taken together, we conclude that the expression levels and specific combination of keratins impinge on cell migration by conferring biomechanical properties on any given epithelial cell affecting cytoplasmic viscoelasticity and adhesion to neighboring cells and the ECM.
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12
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Ribeiro D, Planchon S, Leclercq C, Raundrup K, Alves S, Bessa R, Renaut J, Almeida A. The muscular, hepatic and adipose tissues proteomes in muskox (Ovibos moschatus): Differences between males and females. J Proteomics 2019; 208:103480. [DOI: 10.1016/j.jprot.2019.103480] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/28/2019] [Accepted: 08/02/2019] [Indexed: 02/07/2023]
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Xue L, Lu X, He J, Zhang T, Wu X, Zhang Y, Wang N, An Z, Xu J, Geng Y. Serum CK 18-M30 reflect liver pathological severity during NAFLD progression in a rat model. Pathol Res Pract 2018; 214:1778-1786. [PMID: 30149902 DOI: 10.1016/j.prp.2018.08.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 08/04/2018] [Accepted: 08/18/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND CK 18-M30 was increased in patients with NAFLD. However, little is known about the relationship between CK 18-M30 and NAFLD progression. We aimed to analyze the variety of CK 18-M30 and other metabolism indices during NAFLD progression. Meanwhile, we aimed to investigate the correlation between CK 18-M30 and liver pathology during NAFLD progression. MATERIALS AND METHODS Rats were fed with high sucrose and high fat diet for building NAFLD models. We detected liver pathology by hematoxylin-eosin (HE) staining. We also detected serum CK 18-M30 and metabolism indices including liver enzymes, serum lipids and glycometabolism indices. RESULTS The aggravating degree of liver pathology appeared with prolonged feeding period. The relevance of CK 18-M30 to the severity of liver pathology were higher relative to other indices. CONCLUSION Our results suggested the significance of CK 18-M30 in the progression of NAFLD and provided new evidence for the early diagnosis and prognostic estimation of NAFLD.
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Affiliation(s)
- Li Xue
- Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Xiaolan Lu
- Department of Gastroenterology, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Juntao He
- Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Ting Zhang
- Department of Laboratory, Wuxi Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Wuxi, Jiangsu 214002, PR China.
| | - Xiaokang Wu
- Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Yanping Zhang
- Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Ningning Wang
- Department of Infection Control, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China.
| | - Zhe An
- Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China
| | - Jiru Xu
- Department of Immunology and Pathogenic Biology, Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, PR China.
| | - Yan Geng
- Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, PR China.
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Jirouskova M, Nepomucka K, Oyman-Eyrilmez G, Kalendova A, Havelkova H, Sarnova L, Chalupsky K, Schuster B, Benada O, Miksatkova P, Kuchar M, Fabian O, Sedlacek R, Wiche G, Gregor M. Plectin controls biliary tree architecture and stability in cholestasis. J Hepatol 2018; 68:1006-1017. [PMID: 29273475 DOI: 10.1016/j.jhep.2017.12.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 11/27/2017] [Accepted: 12/12/2017] [Indexed: 01/09/2023]
Abstract
BACKGROUND & AIMS Plectin, a highly versatile cytolinker protein, controls intermediate filament cytoarchitecture and cellular stress response. In the present study, we investigate the role of plectin in the liver under basal conditions and in experimental cholestasis. METHODS We generated liver-specific plectin knockout (PleΔalb) mice and analyzed them using two cholestatic liver injury models: bile duct ligation (BDL) and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) feeding. Primary hepatocytes and a cholangiocyte cell line were used to address the impact of plectin on keratin filament organization and stability in vitro. RESULTS Plectin deficiency in hepatocytes and biliary epithelial cells led to aberrant keratin filament network organization, biliary tree malformations, and collapse of bile ducts and ductules. Further, plectin ablation significantly aggravated biliary damage upon cholestatic challenge. Coincidently, we observed a significant expansion of A6-positive progenitor cells in PleΔalb livers. After BDL, plectin-deficient bile ducts were prominently dilated with more frequent ruptures corresponding to an increased number of bile infarcts. In addition, more abundant keratin aggregates indicated less stable keratin filaments in PleΔalb hepatocytes. A transmission electron microscopy analysis revealed a compromised tight junction formation in plectin-deficient biliary epithelial cells. In addition, protein profiling showed increased expression of the adherens junction protein E-Cadherin, and inefficient upregulation of the desmosomal protein desmoplakin in response to BDL. In vitro analyses revealed a higher susceptibility of plectin-deficient keratin networks to stress-induced collapse, paralleled by elevated activation of p38 MAP kinase. CONCLUSION Our study shows that by maintaining proper keratin network cytoarchitecture and biliary epithelial stability, plectin plays a critical role in protecting the liver from stress elicited by cholestasis. LAY SUMMARY Plectin is a cytolinker protein capable of interconnecting all three cytoskeletal filament systems and linking them to plasma membrane-bound junctional complexes. In liver, the plectin-controlled cytoskeleton mechanically stabilizes epithelial cells and provides them with the capacity to adapt to increased bile pressure under cholestasis.
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Affiliation(s)
- Marketa Jirouskova
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Katerina Nepomucka
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic; Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Gizem Oyman-Eyrilmez
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Alzbeta Kalendova
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Helena Havelkova
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Lenka Sarnova
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Karel Chalupsky
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Bjoern Schuster
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Oldrich Benada
- Laboratory of Molecular Structure Characterization, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Petra Miksatkova
- Forensic Laboratory of Biologically Active Substances, Department of Chemistry of Natural Compounds, University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Martin Kuchar
- Forensic Laboratory of Biologically Active Substances, Department of Chemistry of Natural Compounds, University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Ondrej Fabian
- Department of Pathology and Molecular Medicine, Charles University, Prague, and University Hospital Motol, Prague, Czech Republic
| | - Radislav Sedlacek
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic; Laboratory of Transgenic Models of Diseases, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Gerhard Wiche
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Austria
| | - Martin Gregor
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic.
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15
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SARNOVA L, GREGOR M. Biliary System Architecture: Experimental Models and Visualization Techniques. Physiol Res 2017; 66:383-390. [DOI: 10.33549/physiolres.933499] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The complex architecture of the liver biliary network represents a structural prerequisite for the formation and secretion of bile as well as excretion of toxic substances through bile ducts. Disorders of the biliary tract affect a significant portion of the worldwide population, often leading to cholestatic liver diseases. Cholestatic liver disease is a condition that results from an impairment of bile formation or bile flow to the gallbladder and duodenum. Cholestasis leads to dramatic changes in biliary tree architecture, worsening liver disease and systemic illness. Recent studies show that the prevalence of cholestatic liver diseases is increasing. The availability of well characterized animal models, as well as development of visualization approaches constitutes a critical asset to develop novel pathogenetic concepts and new treatment strategies.
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Affiliation(s)
| | - M. GREGOR
- Laboratory of Integrative Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
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16
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Keratins Are Altered in Intestinal Disease-Related Stress Responses. Cells 2016; 5:cells5030035. [PMID: 27626448 PMCID: PMC5040977 DOI: 10.3390/cells5030035] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 08/18/2016] [Accepted: 08/25/2016] [Indexed: 12/17/2022] Open
Abstract
Keratin (K) intermediate filaments can be divided into type I/type II proteins, which form obligate heteropolymers. Epithelial cells express type I-type II keratin pairs, and K7, K8 (type II) and K18, K19 and K20 (type I) are the primary keratins found in the single-layered intestinal epithelium. Keratins are upregulated during stress in liver, pancreas, lung, kidney and skin, however, little is known about their dynamics in the intestinal stress response. Here, keratin mRNA, protein and phosphorylation levels were studied in response to murine colonic stresses modeling human conditions, and in colorectal cancer HT29 cells. Dextran sulphate sodium (DSS)-colitis was used as a model for intestinal inflammatory stress, which elicited a strong upregulation and widened crypt distribution of K7 and K20. K8 levels were slightly downregulated in acute DSS, while stress-responsive K8 serine-74 phosphorylation (K8 pS74) was increased. By eliminating colonic microflora using antibiotics, K8 pS74 in proliferating cells was significantly increased, together with an upregulation of K8 and K19. In the aging mouse colon, most colonic keratins were upregulated. In vitro, K8, K19 and K8 pS74 levels were increased in response to lipopolysaccharide (LPS)-induced inflammation in HT29 cells. In conclusion, intestinal keratins are differentially and dynamically upregulated and post-translationally modified during stress and recovery.
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17
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Moch M, Windoffer R, Schwarz N, Pohl R, Omenzetter A, Schnakenberg U, Herb F, Chaisaowong K, Merhof D, Ramms L, Fabris G, Hoffmann B, Merkel R, Leube RE. Effects of Plectin Depletion on Keratin Network Dynamics and Organization. PLoS One 2016; 11:e0149106. [PMID: 27007410 PMCID: PMC4805305 DOI: 10.1371/journal.pone.0149106] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/27/2016] [Indexed: 12/19/2022] Open
Abstract
The keratin intermediate filament cytoskeleton protects epithelial cells against various types of stress and is involved in fundamental cellular processes such as signaling, differentiation and organelle trafficking. These functions rely on the cell type-specific arrangement and plasticity of the keratin system. It has been suggested that these properties are regulated by a complex cycle of assembly and disassembly. The exact mechanisms responsible for the underlying molecular processes, however, have not been clarified. Accumulating evidence implicates the cytolinker plectin in various aspects of the keratin cycle, i.e., by acting as a stabilizing anchor at hemidesmosomal adhesion sites and the nucleus, by affecting keratin bundling and branching and by linkage of keratins to actin filament and microtubule dynamics. In the present study we tested these hypotheses. To this end, plectin was downregulated by shRNA in vulvar carcinoma-derived A431 cells. As expected, integrin β4- and BPAG-1-positive hemidesmosomal structures were strongly reduced and cytosolic actin stress fibers were increased. In addition, integrins α3 and β1 were reduced. The experiments furthermore showed that loss of plectin led to a reduction in keratin filament branch length but did not alter overall mechanical properties as assessed by indentation analyses using atomic force microscopy and by displacement analyses of cytoplasmic superparamagnetic beads using magnetic tweezers. An increase in keratin movement was observed in plectin-depleted cells as was the case in control cells lacking hemidesmosome-like structures. Yet, keratin turnover was not significantly affected. We conclude that plectin alone is not needed for keratin assembly and disassembly and that other mechanisms exist to guarantee proper keratin cycling under steady state conditions in cultured single cells.
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Affiliation(s)
- Marcin Moch
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Reinhard Windoffer
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Nicole Schwarz
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Raphaela Pohl
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Andreas Omenzetter
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Aachen, Germany
| | - Uwe Schnakenberg
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Aachen, Germany
| | - Fabian Herb
- Institute of Imaging & Computer Vision, RWTH Aachen University, Aachen, Germany
| | | | - Dorit Merhof
- Institute of Imaging & Computer Vision, RWTH Aachen University, Aachen, Germany
| | - Lena Ramms
- Institute of Complex Systems, Forschungszentrum Jülich, Jülich, Germany
| | - Gloria Fabris
- Institute of Complex Systems, Forschungszentrum Jülich, Jülich, Germany
| | - Bernd Hoffmann
- Institute of Complex Systems, Forschungszentrum Jülich, Jülich, Germany
| | - Rudolf Merkel
- Institute of Complex Systems, Forschungszentrum Jülich, Jülich, Germany
| | - Rudolf E. Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
- * E-mail:
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18
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Szabo S, Wögenstein KL, Fuchs P. Functional and Genetic Analysis of Epiplakin in Epithelial Cells. Methods Enzymol 2015; 569:261-85. [PMID: 26778563 DOI: 10.1016/bs.mie.2015.06.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Epiplakin is a large member (>700 kDa) of the plakin protein family and exclusively expressed in epithelial cell types. Compared to other plakin proteins epiplakin exhibits an unusual structure as it consists entirely of a variable number of consecutive plakin repeat domains (13 in humans, 16 in mice). The only binding partners of epiplakin identified so far are keratins of simple as well as of stratified epithelia. Epiplakin-deficient mice show no obvious spontaneous phenotype. However, ex vivo studies using epiplakin-deficient primary cells indicated protective functions of epiplakin in response to stress. Recent studies using stress models for organs of the gastrointestinal tract revealed that epiplakin-deficient mice develop more pronounced pancreas and liver injuries than their wild-type littermates. In addition, impaired stress-induced keratin network reorganization was observed in the affected organs, and primary epiplakin-deficient hepatocytes showed reduced tolerance for forced keratin overexpression which could be rescued by a chemical chaperone. These findings indicate protective functions of epiplakin in chaperoning disease-induced keratin reorganization. In this review, we describe some of the methods we used to analyze epiplakin's function with the focus on biochemical and ex vivo techniques.
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Affiliation(s)
- Sandra Szabo
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Karl L Wögenstein
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Peter Fuchs
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria.
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