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Groh AC, Möller-Kerutt A, Gilhaus K, Höffken V, Nedvetsky P, Kleimann S, Behrens M, Ghosh S, Hansen U, Krahn MP, Ebnet K, Pavenstädt H, Ludwig A, Weide T. PALS1 is a key regulator of the lateral distribution of tight junction proteins in renal epithelial cells. J Cell Sci 2024; 137:jcs261303. [PMID: 38265145 DOI: 10.1242/jcs.261303] [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: 05/03/2023] [Accepted: 12/04/2023] [Indexed: 01/25/2024] Open
Abstract
The evolutionarily conserved apical Crumbs (CRB) complex, consisting of the core components CRB3a (an isoform of CRB3), PALS1 and PATJ, plays a key role in epithelial cell-cell contact formation and cell polarization. Recently, we observed that deletion of one Pals1 allele in mice results in functional haploinsufficiency characterized by renal cysts. Here, to address the role of PALS1 at the cellular level, we generated CRISPR/Cas9-mediated PALS1-knockout MDCKII cell lines. The loss of PALS1 resulted in increased paracellular permeability, indicating an epithelial barrier defect. This defect was associated with a redistribution of several tight junction-associated proteins from bicellular to tricellular contacts. PALS1-dependent localization of tight junction proteins at bicellular junctions required its interaction with PATJ. Importantly, reestablishment of the tight junction belt upon transient F-actin depolymerization or upon Ca2+ removal was strongly delayed in PALS1-deficient cells. Additionally, the cytoskeleton regulator RhoA was redistributed from junctions into the cytosol under PALS1 knockout. Together, our data uncover a critical role of PALS1 in the coupling of tight junction proteins to the F-actin cytoskeleton, which ensures their correct distribution along bicellular junctions and the formation of tight epithelial barrier.
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Affiliation(s)
- Ann-Christin Groh
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Annika Möller-Kerutt
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Kevin Gilhaus
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Verena Höffken
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Pavel Nedvetsky
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Medical Cell Biology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Simon Kleimann
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Malina Behrens
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Sujasha Ghosh
- School of Biological Sciences and NTU Institute of Structural Biology (NISB), Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore City, Singapore
| | - Uwe Hansen
- University Hospital of Münster, Institute of Musculoskeletal Medicine (IMM), Head Core Facility Electron Microscopy, Domagkstraße 3, 48149 Münster, Germany
| | - Michael P Krahn
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Medical Cell Biology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Klaus Ebnet
- Institute-associated Research Group "Cell adhesion and cell polarity", Institute of Medical Biochemistry, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Von-Esmarch-Straße 56, 48149 Münster, Germany
| | - Hermann Pavenstädt
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
| | - Alexander Ludwig
- School of Biological Sciences and NTU Institute of Structural Biology (NISB), Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore City, Singapore
| | - Thomas Weide
- University Hospital of Münster (UKM), Internal Medicine D (MedD), Department Molecular Nephrology, Albert-Schweitzer-Campus 1 Building A14, 48149 Münster, Germany
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Jin J, Tang Y, Cao L, Wang X, Chen Y, An G, Zhang H, Pan G, Bao J, Zhou Z. Microsporidia persistence in host impairs epithelial barriers and increases chances of inflammatory bowel disease. Microbiol Spectr 2024; 12:e0361023. [PMID: 38149855 PMCID: PMC10846195 DOI: 10.1128/spectrum.03610-23] [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: 10/10/2023] [Accepted: 11/27/2023] [Indexed: 12/28/2023] Open
Abstract
Microsporidia are intracellular fungus-like pathogens and the infection symptoms include recurrent diarrhea and systematic inflammations. The major infection route of microsporidia is the digestive tract. Since microsporidia are hard to fully eliminate, the interactions and persistence of the pathogen within epithelium may modulate host susceptibility to digestive disorders. In this study, both in vitro and in vivo infection models were applied. The alterations of epithelial barrier integrity, permeability, and tight junction proteins after microsporidia infection were assessed on MDCK/Caco-2 monolayers. The fecal intestinal microbiota and tissue alterations after microsporidia infection were assessed on C57BL/6 mice. Moreover, the susceptibility to develop dextran sulfate sodium (DSS)-induced inflammatory bowel diseases (IBDs) was also analyzed by the murine infection model. The results demonstrated that microsporidia infection increased epithelium permeability, weakened wound healing capability, and destructed tight junction protein zonula occludens-1. Microsporidia infection also dysregulates intestinal microbiota. These impairing effects of microsporidia increased host vulnerability to develop enteritis as shown by the murine model of DSS-induced IBD. Our study is the first to elucidate molecular mechanisms of the damaging effects of microsporidia on host epithelium and pointed out the cryptic threats of latent microsporidia infection to public health as reflected by the increased chances of developing more severe diseases.IMPORTANCEMicrosporidia are widely present in nature and usually cause latent and persistent infections in hosts. Given the fact that the digestive tract is the major infection route, it is of great importance to explore the consequences of microsporidia infection on the intestinal epithelial barrier and the risks to the host. In this study, we demonstrated the destructing effects of microsporidium infection on epithelial barriers manifested as increased epithelial permeability, weakened wound healing ability, and disrupted tight junctions. Moreover, microsporidia made the host more susceptible to dextran sulfate sodium-induced inflammatory bowel disease. These findings provide new evidence for us to better understand and develop novel strategies for microsporidia prevention and disease control.
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Affiliation(s)
- Jiangyan Jin
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Yunlin Tang
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Lu Cao
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Xue Wang
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Yebo Chen
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Guozhen An
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Huarui Zhang
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Guoqing Pan
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Jialing Bao
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Zeyang Zhou
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
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3
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Lu W, Luo D, Chen D, Zhang S, Chen X, Zhou H, Liu Q, Chen S, Liu W. Systematic Study of Paeonol/Madecassoside Co-Delivery Nanoemulsion Transdermal Delivery System for Enhancing Barrier Repair and Anti-Inflammatory Efficacy. Molecules 2023; 28:5275. [PMID: 37446936 DOI: 10.3390/molecules28135275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
Sensitive skin is defined as skin with low tolerance and high reactivity. Natural products, such as paeoniflorin and madecassoside, have unique skin care functionality. However, because they are hampered by the skin barrier, paeoniflorin and madecassoside have difficulty penetrating the stratum corneum, resulting in weakened skin barrier repair and anti-inflammatory effects. In addition, there is a lack of detailed studies on the efficacy of paeonol and madecassic in human skin, especially in 3D skin models and clinical trials. To overcome the low transdermal delivery issue, we developed nanoemulsions (PM-NEs) loaded with paeonol and madecassoside to improve their delivery efficiency and promote sensitive skin repair and anti-inflammation effects. Furthermore, systematic evaluations of the efficacy in cell line models, 3D skin models, and clinical trials were conducted. The PM-NEs effectively improved the efficacy of paeonol and madecassoside glucoside transdermal penetration and retention and enhanced cellular uptake. Cellular assays and 3D epidermal models showed that the PM-NEs significantly promoted the secretion of filamentous protein, aquaporin 3, Claudin-1, and hyaluronic acid, and considerably inhibited the secretion of interleukin 1α, interleukin 6, tumor necrosis factor-α, and prostaglandin E2 compared to free components. Notably, clinical trial data showed that the PM-NEs significantly reduced transepidermal water loss, a* values, erythropoietin, the amount of non-inflammatory acne, and the amount of inflammatory acne in the facial skin. Three levels of systematic studies suggest that co-delivery of paeoniflorin and madecassoside via nanoemulsions is a promising strategy to improve topical delivery efficiency and anti-inflammatory repair efficacy in sensitive skin.
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Affiliation(s)
- Wangwang Lu
- Guangzhou Jiyan Cosmetics Technology Co., Ltd., Guangzhou 510275, China
| | - Dan Luo
- National Engineering Research Center for Nanomedicine, Huazhong University of Science and Technology, Wuhan 430075, China
| | - Dan Chen
- National Engineering Research Center for Nanomedicine, Huazhong University of Science and Technology, Wuhan 430075, China
| | - Shuting Zhang
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xuan Chen
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Hong Zhou
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qian Liu
- Guangzhou Jiyan Cosmetics Technology Co., Ltd., Guangzhou 510275, China
| | - Siyuan Chen
- Institute for Biomaterials, Tech Institute for Advanced Materials, College of Materials Science and Engineering, Suqian Advanced Materials Industry Technology Innovation Center, NJTech-BARTY Joint Research Center for Innovative Medical Technology, Nanjing Tech University, Nanjing 211816, China
| | - Wei Liu
- National Engineering Research Center for Nanomedicine, Huazhong University of Science and Technology, Wuhan 430075, China
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
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Gerlach GF, Imseis ZH, Cooper SL, Santos AN, O’Brien LL. Mapping of the podocin proximity-dependent proteome reveals novel components of the kidney podocyte foot process. Front Cell Dev Biol 2023; 11:1195037. [PMID: 37325559 PMCID: PMC10262054 DOI: 10.3389/fcell.2023.1195037] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/03/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction: The unique architecture of glomerular podocytes is integral to kidney filtration. Interdigitating foot processes extend from the podocyte cell body, wrap around fenestrated capillaries, and form specialized junctional complexes termed slit diaphragms to create a molecular sieve. However, the full complement of proteins which maintain foot process integrity, and how this localized proteome changes with disease, remain to be elucidated. Methods: Proximity-dependent biotin identification (BioID) enables the identification of spatially localized proteomes. To this end, we developed a novel in vivo BioID knock-in mouse model. We utilized the slit diaphragm protein podocin (Nphs2) to create a podocin-BioID fusion. Podocin-BioID localizes to the slit diaphragm, and biotin injection leads to podocyte-specific protein biotinylation. We isolated the biotinylated proteins and performed mass spectrometry to identify proximal interactors. Results and Discussion: Gene ontology analysis of 54 proteins specifically enriched in our podocin-BioID sample revealed 'cell junctions,' 'actin binding,' and 'cytoskeleton organization' as top terms. Known foot process components were identified, and we further uncovered two novel proteins: the tricellular junctional protein Ildr2 and the CDC42 and N-WASP interactor Fnbp1l. We confirmed that Ildr2 and Fnbp1l are expressed by podocytes and partially colocalize with podocin. Finally, we investigated how this proteome changes with age and uncovered a significant increase in Ildr2. This was confirmed by immunofluorescence on human kidney samples and suggests altered junctional composition may preserve podocyte integrity. Together, these assays have led to new insights into podocyte biology and support the efficacy of utilizing BioID in vivo to interrogate spatially localized proteomes in health, aging, and disease.
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Affiliation(s)
| | | | | | | | - Lori L. O’Brien
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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Wang Y, Zhou H, Che Y, Wan X, Ding X, Zheng S, Wu C, Qin M, Xu Y, Yu Y, Kulyar MFEA, Li K, Wu Y. Emblica officinalis mitigates intestinal toxicity of mice by modulating gut microbiota in lead exposure. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 253:114648. [PMID: 36812873 DOI: 10.1016/j.ecoenv.2023.114648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/05/2023] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Lead (Pb) contamination has been affecting public health for decades. As a plant-derived medicine, the safety and effectiveness of Emblica officinalis (E. officinalis) fruit extract has been emphasized. The current study focused on mitigating the adverse effects of lead (Pb) exposure in reducing its toxicity worldwide. According to our findings, E. officinalis significantly improved weight loss and colon length shortening (p < 0.05 or p < 0.01). The data of colon histopathology and serum levels of inflammatory cytokines indicated a positive impact to the colonic tissue and inflammatory cell infiltration in a dose-dependent manner. Moreover, we confirmed the expression level improvement of tight junction proteins (TJPs), including ZO-1, Claudin-1, and Occludin. Furthermore, we found that the abundance of some commensal species necessary for maintaining homeostasis and other beneficial function decreased in Pb exposure model, while a remarkable reversion impact was noticed on the intestinal microbiome composition in the treatment group. These findings were consistent with our speculations that E. officinalis could mitigate the adverse effects caused by Pb in alleviating intestinal tissue damage, intestinal barrier disruption, and inflammation. Meanwhile, the variations in gut microbiota might drive the fulfilling current impact. Hence, the present study could provide the theoretical basis for mitigating intestinal toxicity induced by Pb exposure with the help of E. officinalis.
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Affiliation(s)
- Yaping Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China; College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Hui Zhou
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yanyun Che
- Engineering Laboratory for National Healthcare Theories and Products of Yunnan Province, Yunnan University of Chinese Medicine, Kunming 650500, PR China
| | - Xin Wan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiaoxue Ding
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Shengnan Zheng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Chenyang Wu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, PR China
| | - Miao Qin
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yanling Xu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yi Yu
- Department of Anesthesiology, Affiliated Stomatological Hospital, Nanjing Medical University, Nanjing 210029, PR China
| | - Muhammad Fakhar-E-Alam Kulyar
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China; College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Kun Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China; Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yi Wu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China; Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China.
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Breaking the Gingival Barrier in Periodontitis. Int J Mol Sci 2023; 24:ijms24054544. [PMID: 36901974 PMCID: PMC10003416 DOI: 10.3390/ijms24054544] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 03/02/2023] Open
Abstract
The break of the epithelial barrier of gingiva has been a subject of minor interest, albeit playing a key role in periodontal pathology, transitory bacteraemia, and subsequent systemic low-grade inflammation (LGI). The significance of mechanically induced bacterial translocation in gingiva (e.g., via mastication and teeth brushing) has been disregarded despite the accumulated knowledge of mechanical force effects on tight junctions (TJs) and subsequent pathology in other epithelial tissues. Transitory bacteraemia is observed as a rule in gingival inflammation, but is rarely observed in clinically healthy gingiva. This implies that TJs of inflamed gingiva deteriorate, e.g., via a surplus of lipopolysaccharide (LPS), bacterial proteases, toxins, Oncostatin M (OSM), and neutrophil proteases. The inflammation-deteriorated gingival TJs rupture when exposed to physiological mechanical forces. This rupture is characterised by bacteraemia during and briefly after mastication and teeth brushing, i.e., it appears to be a dynamic process of short duration, endowed with quick repair mechanisms. In this review, we consider the bacterial, immune, and mechanical factors responsible for the increased permeability and break of the epithelial barrier of inflamed gingiva and the subsequent translocation of both viable bacteria and bacterial LPS during physiological mechanical forces, such as mastication and teeth brushing.
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7
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Zhou M, Zhao W, Xue W, Liu J, Yu Z. Potential antihypertensive mechanism of egg white-derived peptide QIGLF revealed by proteomic analysis. Int J Biol Macromol 2022; 218:439-446. [PMID: 35878667 DOI: 10.1016/j.ijbiomac.2022.07.149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/05/2022] [Accepted: 07/19/2022] [Indexed: 02/06/2023]
Abstract
Previous work has shown that egg white-derived peptide QIGLF has significant in vivo antihypertensive activity. This study aimed to clarify the antihypertensive mechanisms of QIGLF on spontaneously hypertensive rats (SHRs) by a serum proteomic approach. Here, the tandem mass tag (TMT) quantitative proteomic was performed to discover serum protein changes in SHRs with QIGLF. As a result, SHRs with 4 weeks of QIGLF treatment have distinct serum protein expression profiles by principal component and Pearson's correlation coefficient analysis. Based on Gene Ontology (GO) annotation, oxygen transport and organelle fusion were found to be a regulated major biological process. Besides, aldosterone regulated sodium reabsorption, mitophagy, gap junction, and tight junction were significantly regulated based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. QIGLF might exert antihypertensive effects in the SHRs by inhibiting Na+ reabsorption and oxidative stress, restoring gap junction and tight junction.
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Affiliation(s)
- Mingjie Zhou
- School of Food Science and Engineering, Hainan University, Haikou 570228, PR China; College of Food Science and Engineering, Bohai University, Jinzhou 121013, PR China
| | - Wenzhu Zhao
- School of Food Science and Engineering, Hainan University, Haikou 570228, PR China
| | - Wenjun Xue
- College of Food Science and Engineering, Bohai University, Jinzhou 121013, PR China
| | - Jingbo Liu
- Lab of Nutrition and Functional Food, Jilin University, Changchun 130062, PR China
| | - Zhipeng Yu
- School of Food Science and Engineering, Hainan University, Haikou 570228, PR China.
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8
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Shashikanth N, France MM, Xiao R, Haest X, Rizzo HE, Yeste J, Reiner J, Turner JR. Tight junction channel regulation by interclaudin interference. Nat Commun 2022; 13:3780. [PMID: 35773259 PMCID: PMC9246906 DOI: 10.1038/s41467-022-31587-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 06/23/2022] [Indexed: 02/06/2023] Open
Abstract
Tight junctions form selectively permeable seals across the paracellular space. Both barrier function and selective permeability have been attributed to members of the claudin protein family, which can be categorized as pore-forming or barrier-forming. Here, we show that claudin-4, a prototypic barrier-forming claudin, reduces paracellular permeability by a previously unrecognized mechanism. Claudin-4 knockout or overexpression has minimal effects on tight junction permeability in the absence of pore-forming claudins. However, claudin-4 selectively inhibits flux across cation channels formed by claudins 2 or 15. Claudin-4-induced loss of claudin channel function is accompanied by reduced anchoring and subsequent endocytosis of pore-forming claudins. Analyses in nonepithelial cells show that claudin-4, which is incapable of independent polymerization, disrupts polymeric strands and higher order meshworks formed by claudins 2, 7, 15, and 19. This process of interclaudin interference, in which one claudin disrupts higher order structures and channels formed by a different claudin, represents a previously unrecognized mechanism of barrier regulation.
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Affiliation(s)
- Nitesh Shashikanth
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Marion M France
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Ruyue Xiao
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Xenia Haest
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Heather E Rizzo
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Jose Yeste
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
- Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Bellaterra, Spain
| | - Johannes Reiner
- Division of Gastroenterology and Endocrinology, Department of Medicine II, Rostock University Medical Center, Ernst-Heydemann-Str. 6, Rostock, Germany
| | - Jerrold R Turner
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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9
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Kuo WT, Odenwald MA, Turner JR, Zuo L. Tight junction proteins occludin and ZO-1 as regulators of epithelial proliferation and survival. Ann N Y Acad Sci 2022; 1514:21-33. [PMID: 35580994 PMCID: PMC9427709 DOI: 10.1111/nyas.14798] [Citation(s) in RCA: 83] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Epithelial cells are the first line of mucosal defense. In the intestine, a single layer of epithelial cells must establish a selectively permeable barrier that supports nutrient absorption and waste secretion while preventing the leakage of potentially harmful luminal materials. Key to this is the tight junction, which seals the paracellular space and prevents unrestricted leakage. The tight junction is a protein complex established by interactions between members of the claudin, zonula occludens, and tight junction-associated MARVEL protein (TAMP) families. Claudins form the characteristic tight junction strands seen by freeze-fracture microscopy and create paracellular channels, but the functions of ZO-1 and occludin, founding members of the zonula occludens and TAMP families, respectively, are less well defined. Recent studies have revealed that these proteins have essential noncanonical (nonbarrier) functions that allow them to regulate epithelial apoptosis and proliferation, facilitate viral entry, and organize specialized epithelial structures. Surprisingly, neither is required for intestinal barrier function or overall health in the absence of exogenous stressors. Here, we provide a brief overview of ZO-1 and occludin canonical (barrier-related) functions, and a more detailed examination of their noncanonical functions.
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Affiliation(s)
- Wei-Ting Kuo
- Graduate Institute of Oral Biology, National Taiwan University, Taipei, Taiwan.,Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | | | - Jerrold R Turner
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Li Zuo
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Anhui Medical University, Hefei, China
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10
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Monaco A, Axis J, Amsler K. Simple graphical approach to investigate differences in transepithelial paracellular leak pathway permeability. Physiol Rep 2022; 10:e15202. [PMID: 35274827 PMCID: PMC8915387 DOI: 10.14814/phy2.15202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023] Open
Abstract
Although many studies have reported differences in epithelial paracellular Leak Pathway permeability following genetic manipulations and treatment with various agents, the basis for these differences remains mostly unclear. Two primary mechanisms which could underlie differences in Leak Pathway permeability are differences in the density of Leak Pathway openings and differences in the opening size. Using a computational approach, we demonstrate that these two possibilities can be readily distinguished graphically by comparing the apparent paracellular permeabilities of a size panel of solutes measured across different cell layers. Using this approach, we demonstrated that depletion of ZO-1 protein in MDCK Type II renal epithelial cells decreased Leak Pathway opening size and increased opening density. Depletion of ZO-2 protein either had no effect or minimally decreased opening size and did not markedly change opening density. Comparison of MDCK Type II cells with MDCK Type I cells revealed that Type I cells exhibited a substantially smaller Leak Pathway permeability than did Type II cells. This lower permeability was due to a decrease in opening density with little or no change in opening size. These results demonstrate the utility of this approach to provide insights into the basis for observed differences in epithelial Leak Pathway permeability. This approach has wide applications including analysis of the molecular basis for Leak Pathway permeability, the effects of specific manipulations on Leak Pathway permeability properties, and the effects of permeation enhancers on Leak Pathway permeability properties.
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Affiliation(s)
- Ashley Monaco
- Department of Biomedical SciencesNYIT College of Osteopathic MedicineOld WestburyNew YorkUSA
| | - Josephine Axis
- Department of Biomedical SciencesNYIT College of Osteopathic MedicineOld WestburyNew YorkUSA
| | - Kurt Amsler
- Department of Biomedical SciencesNYIT College of Osteopathic MedicineOld WestburyNew YorkUSA
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11
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Yang HY, Liang ZH, Xie JL, Wu Q, Qin YY, Zhang SY, Tang GD. Gelsolin impairs barrier function in pancreatic ductal epithelial cells by actin filament depolymerization in hypertriglyceridemia‑induced pancreatitis in vitro. Exp Ther Med 2022; 23:290. [PMID: 35317441 PMCID: PMC8908475 DOI: 10.3892/etm.2022.11219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 01/25/2022] [Indexed: 11/23/2022] Open
Abstract
Gelsolin (GSN) is a calcium-regulated actin-binding protein that can sever actin filaments. Notably, actin dynamics affect the structure and function of epithelial barriers. The present study investigated the role of GSN in the barrier function of pancreatic ductal epithelial cells (PDECs) in hypertriglyceridemia-induced pancreatitis (HTGP). The human PDEC cell line HPDE6-C7 underwent GSN knockdown and was treated with caerulein (CAE) + triglycerides (TG). Intracellular calcium levels and the actin filament network were analyzed under a fluorescence microscope. The expression levels of GSN, E-cadherin, nectin-2, ZO-1 and occludin were evaluated by reverse transcription-quantitative polymerase chain reaction and western blotting. Ultrastructural changes in tight junctions were observed by transmission electron microscopy. Furthermore, the permeability of PDECs was analyzed by fluorescein isothiocyanate-dextran fluorescence. The results revealed that CAE + TG increased intracellular calcium levels, actin filament depolymerization and GSN expression, and increased PDEC permeability by decreasing the expression levels of E-cadherin, nectin-2, ZO-1 and occludin compared with the control. Moreover, changes in these markers, with the exception of intracellular calcium levels, were reversed by silencing GSN. In conclusion, GSN may disrupt barrier function in PDECs by causing actin filament depolymerization in HTGP in vitro.
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Affiliation(s)
- Hui-Ying Yang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Zhi-Hai Liang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Jin-Lian Xie
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Qing Wu
- Department of Gastroenterology, The Second Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530007, P.R. China
| | - Ying-Ying Qin
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Shi-Yu Zhang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Guo-Du Tang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
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12
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Mentor S, Makhathini KB, Fisher D. The Role of Cytoskeletal Proteins in the Formation of a Functional In Vitro Blood-Brain Barrier Model. Int J Mol Sci 2022; 23:ijms23020742. [PMID: 35054928 PMCID: PMC8775705 DOI: 10.3390/ijms23020742] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/27/2021] [Accepted: 01/07/2022] [Indexed: 02/05/2023] Open
Abstract
The brain capillary endothelium is highly regulatory, maintaining the chemical stability of the brain’s microenvironment. The role of cytoskeletal proteins in tethering nanotubules (TENTs) during barrier-genesis was investigated using the established immortalized mouse brain endothelial cell line (bEnd5) as an in vitro blood-brain barrier (BBB) model. The morphology of bEnd5 cells was evaluated using both high-resolution scanning electron microscopy and immunofluorescence to evaluate treatment with depolymerizing agents Cytochalasin D for F-actin filaments and Nocodazole for α-tubulin microtubules. The effects of the depolymerizing agents were investigated on bEnd5 monolayer permeability by measuring the transendothelial electrical resistance (TEER). The data endorsed that during barrier-genesis, F-actin and α-tubulin play a cytoarchitectural role in providing both cell shape dynamics and cytoskeletal structure to TENTs forming across the paracellular space to provide cell-cell engagement. Western blot analysis of the treatments suggested a reduced expression of both proteins, coinciding with a reduction in the rates of cellular proliferation and decreased TEER. The findings endorsed that TENTs provide alignment of the paracellular (PC) spaces and tight junction (TJ) zones to occlude bEnd5 PC spaces. The identification of specific cytoskeletal structures in TENTs endorsed the postulate of their indispensable role in barrier-genesis and the maintenance of regulatory permeability across the BBB.
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Affiliation(s)
- Shireen Mentor
- Neurobiology Research Group, Department of Medical Biosciences, University of the Western Cape, Cape Town 7535, South Africa; (S.M.); (K.B.M.)
| | - Khayelihle Brian Makhathini
- Neurobiology Research Group, Department of Medical Biosciences, University of the Western Cape, Cape Town 7535, South Africa; (S.M.); (K.B.M.)
| | - David Fisher
- Neurobiology Research Group, Department of Medical Biosciences, University of the Western Cape, Cape Town 7535, South Africa; (S.M.); (K.B.M.)
- School of Health Professions, University of Missouri, Columbia, MO 65211, USA
- Correspondence: ; Tel.: +27-21-959-2185
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13
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Marchelletta RR, Krishnan M, Spalinger MR, Placone TW, Alvarez R, Sayoc-Becerra A, Canale V, Shawki A, Park YS, Bernts LH, Myers S, Tremblay ML, Barrett KE, Krystofiak E, Kachar B, McGovern DP, Weber CR, Hanson EM, Eckmann L, McCole DF. T cell protein tyrosine phosphatase protects intestinal barrier function by restricting epithelial tight junction remodeling. J Clin Invest 2021; 131:138230. [PMID: 34623320 DOI: 10.1172/jci138230] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 07/22/2021] [Indexed: 12/12/2022] Open
Abstract
Genome-wide association studies revealed that loss-of-function mutations in protein tyrosine phosphatase non-receptor type 2 (PTPN2) increase the risk of developing chronic immune diseases, such as inflammatory bowel disease (IBD) and celiac disease. These conditions are associated with increased intestinal permeability as an early etiological event. The aim of this study was to examine the consequences of deficient activity of the PTPN2 gene product, T cell protein tyrosine phosphatase (TCPTP), on intestinal barrier function and tight junction organization in vivo and in vitro. Here, we demonstrate that TCPTP protected against intestinal barrier dysfunction induced by the inflammatory cytokine IFN-γ by 2 mechanisms: it maintained localization of zonula occludens 1 and occludin at apical tight junctions and restricted both expression and insertion of the cation pore-forming transmembrane protein, claudin-2, at tight junctions through upregulation of the inhibitory cysteine protease, matriptase. We also confirmed that the loss-of-function PTPN2 rs1893217 SNP was associated with increased intestinal claudin-2 expression in patients with IBD. Moreover, elevated claudin-2 levels and paracellular electrolyte flux in TCPTP-deficient intestinal epithelial cells were normalized by recombinant matriptase. Our findings uncover distinct and critical roles for epithelial TCPTP in preserving intestinal barrier integrity, thereby proposing a mechanism by which PTPN2 mutations contribute to IBD.
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Affiliation(s)
- Ronald R Marchelletta
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Moorthy Krishnan
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Marianne R Spalinger
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Taylaur W Placone
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Rocio Alvarez
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Anica Sayoc-Becerra
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Vinicius Canale
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Ali Shawki
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Young Su Park
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Lucas Hp Bernts
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Stephen Myers
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Michel L Tremblay
- Department of Biochemistry and Goodman Cancer Research Centre, Faculty of Medicine and Health Sciences, McGill University, Montréal, Québec, Canada
| | - Kim E Barrett
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Evan Krystofiak
- National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, Maryland, USA
| | - Bechara Kachar
- National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, Maryland, USA
| | - Dermot Pb McGovern
- F. Widjaja Foundation Inflammatory Bowel and Immunobiology Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | | | - Elaine M Hanson
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Lars Eckmann
- Division of Gastroenterology, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Declan F McCole
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
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14
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Monaco A, Ovryn B, Axis J, Amsler K. The Epithelial Cell Leak Pathway. Int J Mol Sci 2021; 22:ijms22147677. [PMID: 34299297 PMCID: PMC8305272 DOI: 10.3390/ijms22147677] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/13/2021] [Accepted: 07/15/2021] [Indexed: 01/08/2023] Open
Abstract
The epithelial cell tight junction structure is the site of the transepithelial movement of solutes and water between epithelial cells (paracellular permeability). Paracellular permeability can be divided into two distinct pathways, the Pore Pathway mediating the movement of small ions and solutes and the Leak Pathway mediating the movement of large solutes. Claudin proteins form the basic paracellular permeability barrier and mediate the movement of small ions and solutes via the Pore Pathway. The Leak Pathway remains less understood. Several proteins have been implicated in mediating the Leak Pathway, including occludin, ZO proteins, tricellulin, and actin filaments, but the proteins comprising the Leak Pathway remain unresolved. Many aspects of the Leak Pathway, such as its molecular mechanism, its properties, and its regulation, remain controversial. In this review, we provide a historical background to the evolution of the Leak Pathway concept from the initial examinations of paracellular permeability. We then discuss current information about the properties of the Leak Pathway and present current theories for the Leak Pathway. Finally, we discuss some recent research suggesting a possible molecular basis for the Leak Pathway.
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Affiliation(s)
- Ashley Monaco
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, Old Westbury, NY 11568, USA; (A.M.); (J.A.)
| | - Ben Ovryn
- Department of Physics, New York Institute of Technology, Northern Boulevard, Old Westbury, NY 11568, USA;
| | - Josephine Axis
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, Old Westbury, NY 11568, USA; (A.M.); (J.A.)
| | - Kurt Amsler
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, Old Westbury, NY 11568, USA; (A.M.); (J.A.)
- Correspondence: ; Tel.: +1-516-686-3716
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15
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Balta I, Marcu A, Linton M, Kelly C, Gundogdu O, Stef L, Pet I, Ward P, Deshaies M, Callaway T, Sopharat P, Gradisteanu-Pircalabioru G, Corcionivoschi N. Mixtures of natural antimicrobials can reduce Campylobacter jejuni, Salmonella enterica and Clostridium perfringens infections and cellular inflammatory response in MDCK cells. Gut Pathog 2021; 13:37. [PMID: 34099034 PMCID: PMC8182910 DOI: 10.1186/s13099-021-00433-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/01/2021] [Indexed: 11/10/2022] Open
Abstract
Background The classification of natural antimicrobials as potential antibiotic replacements is still hampered by the absence of clear biological mechanisms behind their mode of action. This study investigated the mechanisms underlying the anti-bacterial effect of a mixture of natural antimicrobials (maltodextrin, citric acid, sodium citrate, malic acid, citrus extract and olive extract) against Campylobacter jejuni RC039, Salmonella enterica SE 10/72 and Clostridium perfringens ATCC® 13124 invasion of Madin–Darby Canine Kidney cells (MDCK). Results Minimum sub-inhibitory concentrations were determined for Campylobacter jejuni (0.25%), Salmonella enterica (0.50%) and Clostridium perfringens (0.50%) required for the in vitro infection assays with MDCK cells. The antimicrobial mixture significantly reduced the virulence of all three pathogens towards MDCK cells and restored the integrity of cellular tight junctions through increased transepithelial resistance (TEER) and higher expression levels of ZO-1 (zonula occludens 1) and occludin. This study also identified the ERK (external regulated kinase) signalling pathway as a key mechanism in blocking the pro-inflammatory cytokine production (IL-1β, IL-6, IL-8, TNF-α) in infected cells. The reduction in hydrogen peroxide (H2O2) production and release by infected MDCK cells, in the presence of the antimicrobial mixture, was also associated with less tetrathionate formed by oxidation of thiosulphate (p < 0.0001). Conclusion The present study describes for the first time that mixtures of natural antimicrobials can prevent the formation of substrates used by bacterial pathogens to grow and survive in anaerobic environments (e.g. tetrathionate). Moreover, we provide further insights into pathogen invasion mechanisms through restoration of cellular structures and describe their ability to block the ERK–MAPK kinase pathway responsible for inflammatory cytokine release
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Affiliation(s)
- Igori Balta
- Food Microbiology, Bacteriology Branch, Veterinary Sciences Division, Agri-Food and Biosciences Institute, 18a Newforge Lane, Belfast, BT9 5PX, Northern Ireland, UK. .,Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine, 400372, Cluj-Napoca, Romania. .,Faculty of Bioengineering of Animal Resources, Banat University of Agricultural Sciences and Veterinary Medicine-King Michael I of Romania, 300645, Timisoara, Romania.
| | - Adela Marcu
- Faculty of Bioengineering of Animal Resources, Banat University of Agricultural Sciences and Veterinary Medicine-King Michael I of Romania, 300645, Timisoara, Romania.
| | - Mark Linton
- Food Microbiology, Bacteriology Branch, Veterinary Sciences Division, Agri-Food and Biosciences Institute, 18a Newforge Lane, Belfast, BT9 5PX, Northern Ireland, UK
| | - Carmel Kelly
- Food Microbiology, Bacteriology Branch, Veterinary Sciences Division, Agri-Food and Biosciences Institute, 18a Newforge Lane, Belfast, BT9 5PX, Northern Ireland, UK
| | - Ozan Gundogdu
- Department of Infection Biology, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, WC1E 7HT, London, UK
| | - Lavinia Stef
- Faculty of Bioengineering of Animal Resources, Banat University of Agricultural Sciences and Veterinary Medicine-King Michael I of Romania, 300645, Timisoara, Romania
| | - Ioan Pet
- Faculty of Bioengineering of Animal Resources, Banat University of Agricultural Sciences and Veterinary Medicine-King Michael I of Romania, 300645, Timisoara, Romania
| | | | | | - Todd Callaway
- Department of Animal and Dairy Science, University of Georgia, Athens, GA, USA
| | | | | | - Nicolae Corcionivoschi
- Food Microbiology, Bacteriology Branch, Veterinary Sciences Division, Agri-Food and Biosciences Institute, 18a Newforge Lane, Belfast, BT9 5PX, Northern Ireland, UK. .,Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine, 400372, Cluj-Napoca, Romania. .,Faculty of Bioengineering of Animal Resources, Banat University of Agricultural Sciences and Veterinary Medicine-King Michael I of Romania, 300645, Timisoara, Romania.
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16
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Chánez-Paredes S, Montoya-García A, Castro-Ochoa KF, García-Cordero J, Cedillo-Barrón L, Shibayama M, Nava P, Flemming S, Schlegel N, Gautreau AM, Vargas-Robles H, Mondragón-Flores R, Schnoor M. The Arp2/3 Inhibitory Protein Arpin Is Required for Intestinal Epithelial Barrier Integrity. Front Cell Dev Biol 2021; 9:625719. [PMID: 34012961 PMCID: PMC8128147 DOI: 10.3389/fcell.2021.625719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 03/17/2021] [Indexed: 12/23/2022] Open
Abstract
The intestinal epithelial barrier (IEB) depends on stable interepithelial protein complexes such as tight junctions (TJ), adherens junctions (AJ), and the actin cytoskeleton. During inflammation, the IEB is compromised due to TJ protein internalization and actin remodeling. An important actin regulator is the actin-related protein 2/3 (Arp2/3) complex, which induces actin branching. Activation of Arp2/3 by nucleation-promoting factors is required for the formation of epithelial monolayers, but little is known about the relevance of Arp2/3 inhibition and endogenous Arp2/3 inhibitory proteins for IEB regulation. We found that the recently identified Arp2/3 inhibitory protein arpin was strongly expressed in intestinal epithelial cells. Arpin expression decreased in response to tumor necrosis factor (TNF)α and interferon (IFN)γ treatment, whereas the expression of gadkin and protein interacting with protein C-kinase α-subunit 1 (PICK1), other Arp2/3 inhibitors, remained unchanged. Of note, arpin coprecipitated with the TJ proteins occludin and claudin-1 and the AJ protein E-cadherin. Arpin depletion altered the architecture of both AJ and TJ, increased actin filament content and actomyosin contractility, and significantly increased epithelial permeability, demonstrating that arpin is indeed required for maintaining IEB integrity. During experimental colitis in mice, arpin expression was also decreased. Analyzing colon tissues from ulcerative colitis patients by Western blot, we found different arpin levels with overall no significant changes. However, in acutely inflamed areas, arpin was significantly reduced compared to non-inflamed areas. Importantly, patients receiving mesalazine had significantly higher arpin levels than untreated patients. As arpin depletion (theoretically meaning more active Arp2/3) increased permeability, we wanted to know whether Arp2/3 inhibition would show the opposite. Indeed, the specific Arp2/3 inhibitor CK666 ameliorated TNFα/IFNγ-induced permeability in established Caco-2 monolayers by preventing TJ disruption. CK666 treatment also attenuated colitis development, colon tissue damage, TJ disruption, and permeability in dextran sulphate sodium (DSS)-treated mice. Our results demonstrate that loss of arpin triggers IEB dysfunction during inflammation and that low arpin levels can be considered a novel hallmark of acute inflammation.
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Affiliation(s)
| | | | | | | | | | - Mineko Shibayama
- Department of Infectomics and Molecular Pathogenesis, CINVESTAV-IPN, Mexico City, Mexico
| | - Porfirio Nava
- Department of Physiology, Biophysics and Neurosciences, CINVESTAV-IPN, Mexico City, Mexico
| | - Sven Flemming
- Department of Surgery I, University Hospital Würzburg, Würzburg, Germany
| | - Nicolas Schlegel
- Department of Surgery I, University Hospital Würzburg, Würzburg, Germany
| | | | | | | | - Michael Schnoor
- Department of Molecular Biomedicine, CINVESTAV-IPN, Mexico City, Mexico
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17
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Rouaud F, Sluysmans S, Flinois A, Shah J, Vasileva E, Citi S. Scaffolding proteins of vertebrate apical junctions: structure, functions and biophysics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183399. [DOI: 10.1016/j.bbamem.2020.183399] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 06/05/2020] [Accepted: 06/11/2020] [Indexed: 12/11/2022]
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18
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Wang Y, Brieher WM. CD2AP links actin to PI3 kinase activity to extend epithelial cell height and constrain cell area. J Cell Biol 2020; 219:jcb.201812087. [PMID: 31723006 PMCID: PMC7039212 DOI: 10.1083/jcb.201812087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 08/26/2019] [Accepted: 10/21/2019] [Indexed: 01/03/2023] Open
Abstract
Epithelial cells are categorized as cuboidal versus squamous based on the height of the lateral membrane. Wang and Brieher show that CD2AP links PI3K activity to actin assembly to extend the height of the lateral membrane. Maintaining the correct ratio of apical, basal, and lateral membrane domains is important for epithelial physiology. Here, we show that CD2AP is a critical determinant of epithelial membrane proportions. Depletion of CD2AP or phosphoinositide 3-kinase (PI3K) inhibition results in loss of F-actin and expansion of apical–basal domains, which comes at the expense of lateral membrane height in MDCK cells. We demonstrate that the SH3 domains of CD2AP bind to PI3K and are necessary for PI3K activity along lateral membranes and constraining cell area. Tethering the SH3 domains of CD2AP or p110γ to the membrane is sufficient to rescue CD2AP-knockdown phenotypes. CD2AP and PI3K are both upstream and downstream of actin polymerization. Since CD2AP binds to both actin filaments and PI3K, CD2AP might bridge actin assembly to PI3K activation to form a positive feedback loop to support lateral membrane extension. Our results provide insight into the squamous to cuboidal to columnar epithelial transitions seen in complex epithelial tissues in vivo.
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Affiliation(s)
- Yuou Wang
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, IL
| | - William M Brieher
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, IL
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19
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Liu S, Hu C, Luo Y, Yao K. Genome-wide DNA methylation profiles may reveal new possible epigenetic pathogenesis of sporadic congenital cataract. Epigenomics 2020; 12:771-788. [PMID: 32516005 DOI: 10.2217/epi-2019-0254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Aim: To investigate the possible epigenetic pathogenesis of sporadic congenital cataract. Materials & methods: We conducted whole genome bisulfite sequencing on peripheral blood from sporadic binocular or monocular congenital cataract patients and cataract-free participants. Results: We found massive differentially methylated regions within the whole genomes between any two groups. Meanwhile, we identified five genes (ACTN4, ACTG1, TUBA1A, TUBA1C, TUBB4B) for the binocular and control groups and TUBA1A for the monocular and control groups as the core differentially methylated region-related genes. The proteins encoded by these core genes are involved in building cytoskeleton and intercellular junctions. Conclusion: Changes in the methylation levels of core genes may disturb the function of cytoskeleton and intercellular junctions, eventually leading to sporadic congenital cataract.
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Affiliation(s)
- Siyu Liu
- Eye Center of The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310031, PR China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, Zhejiang Province 310031, PR China
| | - Chenyang Hu
- Eye Center of The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310031, PR China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, Zhejiang Province 310031, PR China
| | - Yueqiu Luo
- Eye Center of The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310031, PR China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, Zhejiang Province 310031, PR China
| | - Ke Yao
- Eye Center of The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310031, PR China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, Zhejiang Province 310031, PR China
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20
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Lynn KS, Peterson RJ, Koval M. Ruffles and spikes: Control of tight junction morphology and permeability by claudins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183339. [PMID: 32389670 DOI: 10.1016/j.bbamem.2020.183339] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/24/2020] [Accepted: 05/01/2020] [Indexed: 02/06/2023]
Abstract
Epithelial barrier function is regulated by a family of transmembrane proteins known as claudins. Functional tight junctions are formed when claudins interact with other transmembrane proteins, cytosolic scaffold proteins and the actin cytoskeleton. The predominant scaffold protein, zonula occludens-1 (ZO-1), directly binds to most claudin C-terminal domains, crosslinking them to the actin cytoskeleton. When imaged by immunofluorescence microscopy, tight junctions most frequently are linear structures that form between tricellular junctions. However, tight junctions also adapt non-linear architectures exhibiting either a ruffled or spiked morphology, which both are responses to changes in claudin engagement of actin filaments. Other terms for ruffled tight junctions include wavy, tortuous, undulating, serpentine or zig-zag junctions. Ruffling is under the control of hypoxia induced factor (HIF) and integrin-mediated signaling, as well as direct mechanical stimulation. Tight junction ruffling is specifically enhanced by claudin-2, antagonized by claudin-1 and requires claudin binding to ZO-1. Tight junction spikes are sites of active vesicle budding and fusion that appear as perpendicular projections oriented towards the nucleus. Spikes share molecular features with focal adherens junctions and tubulobulbar complexes found in Sertoli cells. Lung epithelial cells under stress form spikes due to an increase in claudin-5 expression that directly disrupts claudin-18/ZO-1 interactions. Together this suggests that claudins are not simply passive cargoes controlled by scaffold proteins. We propose a model where claudins specifically influence tight junction scaffold proteins to control interactions with the cytoskeleton as a mechanism that regulates tight junction assembly and function.
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Affiliation(s)
- K Sabrina Lynn
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Raven J Peterson
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Koval
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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21
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Lee EY, Yu JY, Paek AR, Lee SH, Jang H, Cho SY, Kim JH, Kang HG, Yun T, Oh SE, Park SY, You HJ. Targeting TJP1 attenuates cell-cell aggregation and modulates chemosensitivity against doxorubicin in leiomyosarcoma. J Mol Med (Berl) 2020; 98:761-773. [PMID: 32318747 DOI: 10.1007/s00109-020-01909-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/30/2020] [Accepted: 04/03/2020] [Indexed: 12/24/2022]
Abstract
Tight junction protein 1 (TJP1) is a membrane-associated cytosolic protein important for cell-cell communication in intercellular barriers in epithelial and non-epithelial cells. Here, we explored the functional involvement of TJP1 in non-epithelial tumors such as soft tissue sarcoma, especially in leiomyosarcoma (LMS). TJP1 expression in soft tissue sarcoma was analyzed in normal and tumor tissues as well as from public datasets such as the TCGA provisional dataset, in which TJP1 expression was compared with other subtypes such as undifferentiated sarcomas, and myxofibrosarcomas. SK-LMS-1 cell lines with reduced TJP1 expression showed attenuated anchorage-independent colony formation as well as reduced intercellular aggregation on non-coated culture plates compared with control as well as parental SK-LMS-1 cells. Transcriptome profiling following TJP1 knockdown in SK-LMS-1 cells suggested the involvement of several signaling pathways, including NF-κB pathway and growth factor receptor signaling. In addition, TJP1 downregulation induced enhanced response against anti-cancer agents, doxorubicin and gefitinib. Taken together, these results suggest that TJP1 contributes to sarcoma genesis and might be useful therapeutic target. KEY MESSAGES: • TJP1 expression at RNA level higher in tumor than in normal tissues of sarcoma. • Targeting TJP1 attenuates cell-cell aggregation and anchorage-independent growth. • Targeting TJP1 is beneficial in anti-cancer therapy in LMS.
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Affiliation(s)
- Eun-Young Lee
- Division of Translational Science, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea.,Department of Medical Biotechnology, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
| | - Jung Yeon Yu
- Division of Translational Science, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea
| | - A Rome Paek
- Division of Translational Science, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea
| | - So Hee Lee
- Division of Translational Science, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea
| | - Hyonchol Jang
- Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy (NCC-GCSP), National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea.,Division of Cancer Biology, Research Institute, National Cancer Center, Goyang, South Korea
| | - Soo Young Cho
- Clinical Genomic Analysis Branch, Research Institute, National Cancer Center, Goyang, South Korea
| | - June Hyuk Kim
- National Cancer Center Hospital, National Cancer Center, Goyang, South Korea
| | - Hyun Guy Kang
- National Cancer Center Hospital, National Cancer Center, Goyang, South Korea
| | - Tak Yun
- National Cancer Center Hospital, National Cancer Center, Goyang, South Korea
| | - Sung Eun Oh
- National Cancer Center Hospital, National Cancer Center, Goyang, South Korea
| | - Seog Yun Park
- National Cancer Center Hospital, National Cancer Center, Goyang, South Korea
| | - Hye Jin You
- Division of Translational Science, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea. .,Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy (NCC-GCSP), National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi, 10408, South Korea.
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22
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Song H, Zhang J, He W, Wang P, Wang F. Activation of Cofilin Increases Intestinal Permeability via Depolymerization of F-Actin During Hypoxia in vitro. Front Physiol 2019; 10:1455. [PMID: 31849705 PMCID: PMC6901426 DOI: 10.3389/fphys.2019.01455] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 11/11/2019] [Indexed: 12/15/2022] Open
Abstract
Mechanical barriers play a key role in maintaining the normal function of the intestinal mucosa. The barrier function of intestinal epithelial cells is significantly damaged after severe hypoxia. However, the molecular mechanisms underlying this hypoxia-induced damage are still not completely clear. Through the establishment of an in vitro cultured intestinal epithelial cell monolayer model (Caco-2), we treated cells with hypoxia or drugs [jasplakinolide or latrunculin A (LatA)] to detect changes in the transepithelial electrical resistance (TER), the expression of the cellular tight junction (TJ) proteins zonula occludens-1 (ZO-1) and occludin, the distribution of F-actin, the ratio of F-actin/G-actin content, and the expression of the cofilin protein. The results showed that hypoxia and drug treatment could both induce a significant reduction in the TER of the intestinal epithelial cell monolayer and a significant reduction in the expression of the ZO-1 and occludin protein. Hypoxia and LatA could cause a significant reduction in the ratio of F-actin/G-actin content, whereas jasplakinolide caused a significant increase in the ratio of F-actin/G-actin content. After hypoxia, cofilin phosphorylation was decreased. We concluded that the barrier function of the intestinal epithelial cell monolayer was significantly damaged after severe burn injury. The molecular mechanism might be that hypoxia-induced F-actin depolymerization and an imbalance between F-actin and G-actin through cofilin activation resulted in reduced expression and a change in the distribution of cellular TJ proteins.
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Affiliation(s)
- Huapei Song
- Department of Burns, State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Army Medical University, Chongqing, China
| | - Jian Zhang
- Department of Burns, State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Army Medical University, Chongqing, China
| | - Wen He
- Department of Burns, State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Army Medical University, Chongqing, China
| | - Pei Wang
- Department of Burns, State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Army Medical University, Chongqing, China
| | - Fengjun Wang
- Department of Burns, State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Army Medical University, Chongqing, China
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23
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Varadarajan S, Stephenson RE, Miller AL. Multiscale dynamics of tight junction remodeling. J Cell Sci 2019; 132:132/22/jcs229286. [PMID: 31754042 DOI: 10.1242/jcs.229286] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Epithelial cells form tissues that generate biological barriers in the body. Tight junctions (TJs) are responsible for maintaining a selectively permeable seal between epithelial cells, but little is known about how TJs dynamically remodel in response to physiological forces that challenge epithelial barrier function, such as cell shape changes (e.g. during cell division) or tissue stretching (e.g. during developmental morphogenesis). In this Review, we first introduce a framework to think about TJ remodeling across multiple scales: from molecular dynamics, to strand dynamics, to cell- and tissue-scale dynamics. We then relate knowledge gained from global perturbations of TJs to emerging information about local TJ remodeling events, where transient localized Rho activation and actomyosin-mediated contraction promote TJ remodeling to repair local leaks in barrier function. We conclude by identifying emerging areas in the field and propose ideas for future studies that address unanswered questions about the mechanisms that drive TJ remodeling.
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Affiliation(s)
- Saranyaraajan Varadarajan
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, United States
| | - Rachel E Stephenson
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, United States
| | - Ann L Miller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, United States
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24
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Abstract
Tight junctions (TJ) play a central role in the homeostasis of epithelial and endothelial tissues, by providing a semipermeable barrier to ions and solutes, by contributing to the maintenance of cell polarity, and by functioning as signaling platforms. TJ are associated with the actomyosin and microtubule cytoskeletons, and the crosstalk with the cytoskeleton is fundamental for junction biogenesis and physiology. TJ are spatially and functionally connected to adherens junctions (AJ), which are essential for the maintenance of tissue integrity. Mechano-sensing and mechano-transduction properties of several AJ proteins have been characterized during the last decade. However, little is known about how mechanical forces act on TJ and their proteins, how TJ control the mechanical properties of cells and tissues, and what are the underlying molecular mechanisms. Here I review recent studies that have advanced our understanding of the relationships between mechanical force and TJ biology.
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25
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Intestinal Barrier Function in Gluten-Related Disorders. Nutrients 2019; 11:nu11102325. [PMID: 31581491 PMCID: PMC6835310 DOI: 10.3390/nu11102325] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 12/15/2022] Open
Abstract
Gluten-related disorders include distinct disease entities, namely celiac disease, wheat-associated allergy and non-celiac gluten/wheat sensitivity. Despite having in common the contact of the gastrointestinal mucosa with components of wheat and other cereals as a causative factor, these clinical entities have distinct pathophysiological pathways. In celiac disease, a T-cell mediate immune reaction triggered by gluten ingestion is central in the pathogenesis of the enteropathy, while wheat allergy develops as a rapid immunoglobulin E- or non-immunoglobulin E-mediated immune response. In non-celiac wheat sensitivity, classical adaptive immune responses are not involved. Instead, recent research has revealed that an innate immune response to a yet-to-be-defined antigen, as well as the gut microbiota, are pivotal in the development in this disorder. Although impairment of the epithelial barrier has been described in all three clinical conditions, its role as a potential pathogenetic co-factor, specifically in celiac disease and non-celiac wheat sensitivity, is still a matter of investigation. This article gives a short overview of the mucosal barrier of the small intestine, summarizes the aspects of barrier dysfunction observed in all three gluten-related disorders and reviews literature data in favor of a primary involvement of the epithelial barrier in the development of celiac disease and non-celiac wheat sensitivity.
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26
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Chánez-Paredes S, Montoya-García A, Schnoor M. Cellular and pathophysiological consequences of Arp2/3 complex inhibition: role of inhibitory proteins and pharmacological compounds. Cell Mol Life Sci 2019; 76:3349-3361. [PMID: 31073744 PMCID: PMC11105272 DOI: 10.1007/s00018-019-03128-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 02/06/2023]
Abstract
The actin-related protein complex 2/3 (Arp2/3) generates branched actin networks important for many cellular processes such as motility, vesicular trafficking, cytokinesis, and intercellular junction formation and stabilization. Activation of Arp2/3 requires interaction with actin nucleation-promoting factors (NPFs). Regulation of Arp2/3 activity is achieved by endogenous inhibitory proteins through direct binding to Arp2/3 and competition with NPFs or by binding to Arp2/3-induced actin filaments and disassembly of branched actin networks. Arp2/3 inhibition has recently garnered more attention as it has been associated with attenuation of cancer progression, neurotoxic effects during drug abuse, and pathogen invasion of host cells. In this review, we summarize current knowledge on expression, inhibitory mechanisms and function of endogenous proteins able to inhibit Arp2/3 such as coronins, GMFs, PICK1, gadkin, and arpin. Moreover, we discuss cellular consequences of pharmacological Arp2/3 inhibition.
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Affiliation(s)
- Sandra Chánez-Paredes
- Department for Molecular Biomedicine, CINVESTAV-IPN, Av. IPN 2508, San Pedro Zacatenco, GAM, 07360, Mexico City, Mexico
| | - Armando Montoya-García
- Department for Molecular Biomedicine, CINVESTAV-IPN, Av. IPN 2508, San Pedro Zacatenco, GAM, 07360, Mexico City, Mexico
| | - Michael Schnoor
- Department for Molecular Biomedicine, CINVESTAV-IPN, Av. IPN 2508, San Pedro Zacatenco, GAM, 07360, Mexico City, Mexico.
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27
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Tervonen A, Ihalainen TO, Nymark S, Hyttinen J. Structural dynamics of tight junctions modulate the properties of the epithelial barrier. PLoS One 2019; 14:e0214876. [PMID: 30964903 PMCID: PMC6456171 DOI: 10.1371/journal.pone.0214876] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/21/2019] [Indexed: 01/09/2023] Open
Abstract
Tight junctions are dynamic structures that are crucial in establishing the diffusion and electrical barrier of epithelial monolayers. Dysfunctions in the tight junctions can impede this barrier function and lead to many pathological conditions. Unfortunately, detailed understanding of the non-specific permeation pathway through the tight junctions, the so-called leak pathway, is lacking. We created computational models of the leak pathway to describe the two main barrier measures, molecular permeability and transepithelial electric resistance while using common structural dynamics. Our results showed that the proposed alternatives for the leak pathway, the bicellular strand opening dynamics and the tricellular pores, contribute together with distinct degrees, depending on the epithelium. The models can also capture changes in the tight junction barrier caused by changes in tight junction protein composition. In addition, we observed that the molecular permeability was markedly more sensitive to changes in the tight junction structure and strand dynamics compared with transepithelial electric resistance. The results highlight that our model creates a good methodological framework to integrate knowledge on the tight junction structure as well as to provide insights and tools to advance tight junction research.
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Affiliation(s)
- Aapo Tervonen
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
- * E-mail:
| | - Teemu O. Ihalainen
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
| | - Soile Nymark
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
| | - Jari Hyttinen
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
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28
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Van Itallie CM, Lidman KF, Tietgens AJ, Anderson JM. Newly synthesized claudins but not occludin are added to the basal side of the tight junction. Mol Biol Cell 2019; 30:1406-1424. [PMID: 30943107 PMCID: PMC6724697 DOI: 10.1091/mbc.e19-01-0008] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A network of claudin strands creates continuous cell–cell contacts to form the intercellular tight junction barrier; a second protein, occludin, is associated along these strands. The physiological barrier remains stable despite protein turnover, which involves removal and replacement of claudins both in the steady state and during junction remodeling. Here we use a pulse–block–pulse labeling protocol with fluorescent ligands to label SNAP/CLIP-tags fused to claudins and occludin to identify their spatial trafficking pathways and kinetics in Madin–Darby canine kidney monolayers. We find that claudins are first delivered to the lateral membrane and, over time, enter the junction strand network from the basal side; this is followed by slow replacement of older claudins in the strands. In contrast, even at early times, newly synthesized occludin is found throughout the network. Taking the results together with our previous documentation of the mechanism for claudin strand assembly in a fibroblast model, we speculate that newly synthesized claudins are added at strand breaks and free ends; these are most common in the basalmost edge of the junction. In contrast, occludin can be added directly within the strand network. We further demonstrate that claudin trafficking and half-life depend on carboxy-terminal sequences and that different claudins compete for tight junction localization.
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Affiliation(s)
- Christina M Van Itallie
- Laboratory of Tight Junction Structure and Function, National Institutes of Health, Bethesda, MD 20892
| | - Karin Fredriksson Lidman
- Laboratory of Tight Junction Structure and Function, National Institutes of Health, Bethesda, MD 20892
| | - Amber Jean Tietgens
- Laboratory of Tight Junction Structure and Function, National Institutes of Health, Bethesda, MD 20892
| | - James Melvin Anderson
- Laboratory of Tight Junction Structure and Function, National Institutes of Health, Bethesda, MD 20892
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29
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Rho Flares Repair Local Tight Junction Leaks. Dev Cell 2019; 48:445-459.e5. [PMID: 30773490 DOI: 10.1016/j.devcel.2019.01.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 11/12/2018] [Accepted: 01/17/2019] [Indexed: 12/29/2022]
Abstract
Tight junctions contribute to epithelial barrier function by selectively regulating the quantity and type of molecules that cross the paracellular barrier. Experimental approaches to evaluate the effectiveness of tight junctions are typically global, tissue-scale measures. Here, we introduce Zinc-based Ultrasensitive Microscopic Barrier Assay (ZnUMBA), which we used in Xenopus laevis embryos to visualize short-lived, local breaches in epithelial barrier function. These breaches, or leaks, occur as cell boundaries elongate, correspond to visible breaks in the tight junction, and are followed by transient localized Rho activation, or Rho flares. We discovered that Rho flares restore barrier function by driving concentration of tight junction proteins through actin polymerization and ROCK-mediated localized contraction of the cell boundary. We conclude that Rho flares constitute a damage control mechanism that reinstates barrier function when tight junctions become locally compromised because of normally occurring changes in cell shape and tissue tension.
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30
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Arnold TR, Shawky JH, Stephenson RE, Dinshaw KM, Higashi T, Huq F, Davidson LA, Miller AL. Anillin regulates epithelial cell mechanics by structuring the medial-apical actomyosin network. eLife 2019; 8:39065. [PMID: 30702429 PMCID: PMC6424563 DOI: 10.7554/elife.39065] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 01/30/2019] [Indexed: 02/07/2023] Open
Abstract
Cellular forces sculpt organisms during development, while misregulation of cellular mechanics can promote disease. Here, we investigate how the actomyosin scaffold protein anillin contributes to epithelial mechanics in Xenopus laevis embryos. Increased mechanosensitive recruitment of vinculin to cell-cell junctions when anillin is overexpressed suggested that anillin promotes junctional tension. However, junctional laser ablation unexpectedly showed that junctions recoil faster when anillin is depleted and slower when anillin is overexpressed. Unifying these findings, we demonstrate that anillin regulates medial-apical actomyosin. Medial-apical laser ablation supports the conclusion that that tensile forces are stored across the apical surface of epithelial cells, and anillin promotes the tensile forces stored in this network. Finally, we show that anillin's effects on cellular mechanics impact tissue-wide mechanics. These results reveal anillin as a key regulator of epithelial mechanics and lay the groundwork for future studies on how anillin may contribute to mechanical events in development and disease.
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Affiliation(s)
- Torey R Arnold
- Department of Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Joseph H Shawky
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, United States.,Department of Developmental Biology, University of Pittsburgh, Pittsburgh, United States.,Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, United States
| | - Rachel E Stephenson
- Department of Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Kayla M Dinshaw
- Department of Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Tomohito Higashi
- Department of Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Farah Huq
- Department of Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Lance A Davidson
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, United States.,Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, United States
| | - Ann L Miller
- Department of Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, United States
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31
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BAR domain proteins-a linkage between cellular membranes, signaling pathways, and the actin cytoskeleton. Biophys Rev 2018; 10:1587-1604. [PMID: 30456600 DOI: 10.1007/s12551-018-0467-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 10/17/2018] [Indexed: 12/23/2022] Open
Abstract
Actin filament assembly typically occurs in association with cellular membranes. A large number of proteins sit at the interface between actin networks and membranes, playing diverse roles such as initiation of actin polymerization, modulation of membrane curvature, and signaling. Bin/Amphiphysin/Rvs (BAR) domain proteins have been implicated in all of these functions. The BAR domain family of proteins comprises a diverse group of multi-functional effectors, characterized by their modular architecture. In addition to the membrane-curvature sensing/inducing BAR domain module, which also mediates antiparallel dimerization, most contain auxiliary domains implicated in protein-protein and/or protein-membrane interactions, including SH3, PX, PH, RhoGEF, and RhoGAP domains. The shape of the BAR domain itself varies, resulting in three major subfamilies: the classical crescent-shaped BAR, the more extended and less curved F-BAR, and the inverse curvature I-BAR subfamilies. Most members of this family have been implicated in cellular functions that require dynamic remodeling of the actin cytoskeleton, such as endocytosis, organelle trafficking, cell motility, and T-tubule biogenesis in muscle cells. Here, we review the structure and function of mammalian BAR domain proteins and the many ways in which they are interconnected with the actin cytoskeleton.
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32
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Expression of periaxin (PRX) specifically in the human cerebrovascular system: PDZ domain-mediated strengthening of endothelial barrier function. Sci Rep 2018; 8:10042. [PMID: 29968755 PMCID: PMC6030167 DOI: 10.1038/s41598-018-28190-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 06/13/2018] [Indexed: 01/01/2023] Open
Abstract
Regulation of cerebral endothelial cell function plays an essential role in changes in blood-brain barrier permeability. Proteins that are important for establishment of endothelial tight junctions have emerged as critical molecules, and PDZ domain containing-molecules are among the most important. We have discovered that the PDZ-domain containing protein periaxin (PRX) is expressed in human cerebral endothelial cells. Surprisingly, PRX protein is not detected in brain endothelium in other mammalian species, suggesting that it could confer human-specific vascular properties. In endothelial cells, PRX is predominantly localized to the nucleus and not tight junctions. Transcriptome analysis shows that PRX expression suppresses, by at least 50%, a panel of inflammatory markers, of which 70% are Type I interferon response genes; only four genes were significantly activated by PRX expression. When expressed in mouse endothelial cells, PRX strengthens barrier function, significantly increases transendothelial electrical resistance (~35%; p < 0.05), and reduces the permeability of a wide range of molecules. The PDZ domain of PRX is necessary and sufficient for its barrier enhancing properties, since a splice variant (S-PRX) that contains only the PDZ domain, also increases barrier function. PRX also attenuates the permeability enhancing effects of lipopolysaccharide. Collectively, these studies suggest that PRX could potentially regulate endothelial homeostasis in human cerebral endothelial cells by modulating inflammatory gene programs.
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33
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Bilal S, Jaggi S, Janosevic D, Shah N, Teymour S, Voronina A, Watari J, Axis J, Amsler K. ZO-1 protein is required for hydrogen peroxide to increase MDCK cell paracellular permeability in an ERK 1/2-dependent manner. Am J Physiol Cell Physiol 2018; 315:C422-C431. [PMID: 29874107 DOI: 10.1152/ajpcell.00185.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hydrogen peroxide (H2O2) increases paracellular permeability of Madin-Darby canine kidney (MDCK) cells, but the mechanism mediating this effect remains unclear. Treatment of MDCK cells with H2O2 activated ERK 1/2. Inhibition of ERK 1/2 activation blocked the ability of H2O2 to increase paracellular permeability. Knockdown of zonula occludens-1 (ZO-1) protein but not occludin eliminated the ability of H2O2 to increase paracellular permeability. H2O2 treatment did not, however, affect the total cell content or contents of the Triton X-100-soluble and -insoluble fractions for occludin, ZO-1, or ZO-2. H2O2 treatment decreased the number of F-actin stress fibers in the basal portion of the cells. Similar to wild-type MDCK cells, H2O2 increased ERK 1/2 activation in ZO-1 knockdown and occludin knockdown cells. Inhibition of ERK 1/2 activation blocked the increase in paracellular permeability in occludin knockdown cells. ZO-1 knockdown cell paracellular permeability was regulated by PP1, an src inhibitor, indicating that the loss of response to H2O2 was not a general loss of the ability to regulate the paracellular barrier. Inhibition of myosin ATPase activity with blebbistatin increased paracellular permeability in ZO-1 knockdown cells but not in wild-type MDCK cells. H2O2 treatment sensitized wild-type MDCK cells to inhibition of myosin ATPase. Knockdown of TOCA-1 protein, which promotes formation of local branched actin networks, reproduced the effects of ZO-1 protein knockdown. These results demonstrate that H2O2 increases MDCK cell paracellular permeability through activation of ERK 1/2. This H2O2 action requires ZO-1 protein and TOCA-1 protein, suggesting involvement of the actin cytoskeleton.
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Affiliation(s)
- Sahar Bilal
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Shirin Jaggi
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Danielle Janosevic
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Nikita Shah
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Shereen Teymour
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Angelina Voronina
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Jessica Watari
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Josephine Axis
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Kurt Amsler
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
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34
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Abstract
CRISPR is a nuclease guidance system that enables rapid and efficient gene editing of specific DNA sequences within genomes. We review applications of CRISPR for the study and treatment of kidney disease. CRISPR enables functional experiments in cell lines and model organisms to validate candidate genes arising from genetic studies. CRISPR has furthermore been used to establish the first models of genetic disease in human kidney organoids derived from pluripotent stem cells. These gene-edited organoids are providing new insight into the cellular mechanisms of polycystic kidney disease and nephrotic syndrome. CRISPR-engineered cell therapies are currently in clinical trials for cancers and immunologic syndromes, an approach that may be applicable to inflammatory conditions such as lupus nephritis. Use of CRISPR in large domestic species such as pigs raises the possibility of farming kidneys for transplantation to alleviate the shortage of donor organs. However, significant challenges remain, including how to effectively deliver CRISPR to kidneys and how to control gene editing events within the genome. Thorough testing of CRISPR in preclinical models will be critical to the safe and efficacious translation of this powerful young technology into therapies.
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Affiliation(s)
- Nelly M Cruz
- Division of Nephrology, University of Washington School of Medicine, Seattle WA; Kidney Research Institute, University of Washington School of Medicine, Seattle WA; Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle WA; Department of Medicine, University of Washington School of Medicine, Seattle WA
| | - Benjamin S Freedman
- Division of Nephrology, University of Washington School of Medicine, Seattle WA; Kidney Research Institute, University of Washington School of Medicine, Seattle WA; Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle WA; Department of Medicine, University of Washington School of Medicine, Seattle WA.
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35
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Zhao J, Krystofiak ES, Ballesteros A, Cui R, Van Itallie CM, Anderson JM, Fenollar-Ferrer C, Kachar B. Multiple claudin-claudin cis interfaces are required for tight junction strand formation and inherent flexibility. Commun Biol 2018; 1:50. [PMID: 30271933 PMCID: PMC6123731 DOI: 10.1038/s42003-018-0051-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 04/03/2018] [Indexed: 02/07/2023] Open
Abstract
Tight junctions consist of a network of sealing strands that create selective ion permeability barriers between adjoining epithelial or endothelial cells. The current model for tight junction strands consists of paired rows of claudins (Cldn) coupled by a cis interface (X-1) derived from crystalline Cldn15. Here we show that tight junction strands exhibit a broad range of lateral bending, indicating diversity in cis interactions. By combining protein–protein docking, coevolutionary analysis, molecular dynamics, and a mutagenesis screen, we identify a new Cldn–Cldn cis interface (Cis-1) that shares interacting residues with X-1 but has an ~ 17° lateral rotation between monomers. In addition, we found that a missense mutation in a Cldn14 that causes deafness and contributes stronger to Cis-1 than to X-1 prevents strand formation in cultured cells. Our results suggest that Cis-1 contributes to the inherent structural flexibility of tight junction strands and is required for maintaining permeability barrier function and hearing. Jun Zhao, Evan S. Krystofiak, and colleagues identified a new cis interface (Cis-1) essential for the formation of normal tight junctions. This study suggests that Cis-1 contributes to maintaining structural flexibility of tight junction strands for proper ion balance and hearing.
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Affiliation(s)
- Jun Zhao
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, 35A Convent Drive, Bethesda, MD, 20892, USA.,Cancer and Inflammation Program, National Cancer Institute, Frederick, MD, 21702, USA
| | - Evan S Krystofiak
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, 35A Convent Drive, Bethesda, MD, 20892, USA
| | - Angela Ballesteros
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, 35A Convent Drive, Bethesda, MD, 20892, USA.,Molecular Physiology and Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD, 20892, USA
| | - Runjia Cui
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, 35A Convent Drive, Bethesda, MD, 20892, USA
| | - Christina M Van Itallie
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, 50 South Drive, Bethesda, MD, 20892, USA
| | - James M Anderson
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, 50 South Drive, Bethesda, MD, 20892, USA
| | - Cristina Fenollar-Ferrer
- Computational Structural Biology Unit, National Institute of Neurological Disorders and Stroke, 35 Convent Drive, Bethesda, MD, 20892, USA. .,Laboratory of Molecular & Cellular Neurobiology, National Institute of Mental Health, 35 Convent Drive, Bethesda, MD, 20892, USA.
| | - Bechara Kachar
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, 35A Convent Drive, Bethesda, MD, 20892, USA.
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36
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Malinova TS, Huveneers S. Sensing of Cytoskeletal Forces by Asymmetric Adherens Junctions. Trends Cell Biol 2018; 28:328-341. [DOI: 10.1016/j.tcb.2017.11.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 12/13/2022]
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37
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Miller KA, Garza-Mayers AC, Leung Y, Goldberg MB. Identification of interactions among host and bacterial proteins and evaluation of their role early during Shigella flexneri infection. MICROBIOLOGY-SGM 2018; 164:540-550. [PMID: 29488864 DOI: 10.1099/mic.0.000637] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Shigella species cause diarrhoea by invading and spreading through the epithelial layer of the human colon. The infection triggers innate immune responses in the host that the bacterium combats by translocating into the host cell cytosol via a type 3 secretion system bacterial effector proteins that interfere with host processes. We previously demonstrated that interaction of the Shigella type 3 secreted effector protein IcsB with the host protein Toca-1 inhibits the innate immune response microtubule-associated protein light-chain 3 (LC3)-associated phagocytosis, and that IcsB interaction with Toca-1 is required for inhibition of this host response. Here, we show that Toca-1 in vitro precipitated not only IcsB, but also the type 3 secreted proteins OspC3, IpgD and IpaB. OspC3 and IpgD precipitation with Toca-1 was dependent on IcsB. Early during infection, most of these proteins localized near intracellular Shigella. We examined whether interactions among these proteins restrict innate host cell responses other than LC3-associated phagocytosis. In infected cells, OspC3 blocks production and secretion of the mature pro-inflammatory cytokine IL-18; however, we found that interaction of OspC3 with IcsB, either directly or indirectly via Toca-1, was not required for OspC3-mediated restriction of IL-18 production. These results indicate that interactions of the host protein Toca-1 with a subset of type 3 effector proteins contribute to the established function of some, but not all involved, effector proteins.
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Affiliation(s)
- Kelly A Miller
- Department of Medicine, Division of Infectious Diseases, Massachusetts General Hospital, Cambridge, Massachusetts, USA.,Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Anna Cristina Garza-Mayers
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA.,Present address: Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Yiuka Leung
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA.,Present address: Department of Anesthesiology, The Hardin Memorial Hospital Foundation, Inc., Elizabethtown, Kentucky, USA
| | - Marcia B Goldberg
- Department of Medicine, Division of Infectious Diseases, Massachusetts General Hospital, Cambridge, Massachusetts, USA.,Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA
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38
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Fredriksson-Lidman K, Van Itallie CM, Tietgens AJ, Anderson JM. Sorbin and SH3 domain-containing protein 2 (SORBS2) is a component of the acto-myosin ring at the apical junctional complex in epithelial cells. PLoS One 2017; 12:e0185448. [PMID: 28961272 PMCID: PMC5621683 DOI: 10.1371/journal.pone.0185448] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/12/2017] [Indexed: 12/30/2022] Open
Abstract
SORBS2 is a scaffolding protein associated with Abl/Arg non-receptor tyrosine kinase pathways and is known to interact with actin and several other cytoskeletal proteins in various cell types. Previous BioID proximity labeling of tight and adherens junction proteins suggested that SORBS2 is a component of the apical junction complex of epithelial cells. We asked whether SORBS2 plays a previously unappreciated role in controlling perijunctional actin and tight junction barrier function. Using super resolution imaging we confirmed that SORBS2 is localized at the apical junction complex but farther from the membrane than ZO-1 and located partially overlapping both the tight- and adherens junctions with a periodic concentration that alternates with myosin IIB in polarized epithelial cells. Overexpression of GFP-SORBS2 recruited alpha-actinin, vinculin and N-WASP, and possibly CIP4 to cellular junctions. However, CRISPR-Cas9 knock-out of SORBS2 did not alter the localization- or immunofluorescent staining intensity of these or several other junctional- and cytoskeletal proteins. SORBS2 knock-out also did not affect the barrier function as measured by TER and dextran flux; nor did it change actin-dependent junction re-assembly as measured by Ca2+-switch and Latrunculin-B wash-out assays. The kinetics of HGF-induced cell scattering and wound healing, and dextran flux increase induced by PDGF also were unaffected by SORBS2 knock-out. SORBS2 concentrates with apical junctional actin that accumulates in response to knock-down of ZO-1 and ZO-2. In spite of our finding that SORBS2 is clearly a component of the apical junction complex, it does not appear to be required for either normal tight- or adherens junction assembly, structure or function or for growth factor-mediated changes in tight junction dynamics.
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Affiliation(s)
- Karin Fredriksson-Lidman
- Laboratory of Tight Junction Structure and Function, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
| | - Christina M. Van Itallie
- Laboratory of Tight Junction Structure and Function, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Amber J. Tietgens
- Laboratory of Tight Junction Structure and Function, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - James M. Anderson
- Laboratory of Tight Junction Structure and Function, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
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39
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Riz I, Hawley RG. Increased expression of the tight junction protein TJP1/ZO-1 is associated with upregulation of TAZ-TEAD activity and an adult tissue stem cell signature in carfilzomib-resistant multiple myeloma cells and high-risk multiple myeloma patients. Oncoscience 2017; 4:79-94. [PMID: 28966941 PMCID: PMC5616201 DOI: 10.18632/oncoscience.356] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 06/23/2017] [Indexed: 02/07/2023] Open
Abstract
Tight junction protein 1 (TJP1) has recently been proposed as a biomarker to identify multiple myeloma (MM) patients most likely to respond to bortezomib- and carfilzomib-based proteasome inhibitor regimens. Herein we report increased expression of TJP1 during the adaptive response mediating carfilzomib resistance in the LP-1/Cfz MM cell line. Moreover, increased TJP1 expression delineated a subset of relapsed/refractory MM patients on bortezomib-based therapy sharing an LP-1/Cfz-like phenotype characterized by activation of interacting transcriptional effectors of the Hippo signaling cascade (TAZ and TEAD1) and an adult tissue stem cell signature. siRNA-mediated knockdown of TJP1 or TAZ/TEAD1 partially sensitized LP-1/Cfz cells to carfilzomib. Connectivity Map analysis identified translation inhibitors as candidate therapeutic agents targeting this molecular phenotype. We confirmed this prediction by showing that homoharringtonine (omacetaxine mepesuccinate) — the first translation inhibitor to be approved by the U.S. Food and Drug Administration — displayed potent cytotoxic activity on LP-1/Cfz cells. Homoharringtonine treatment reduced the levels of TAZ and TEAD1 as well as the MM-protective proteins Nrf2 and MCL1. Thus, our data suggest the importance of further studies evaluating translation inhibitors in relapsed/refractory MM. On the other hand, use of TJP1 as a MM biomarker for proteasome inhibitor sensitivity requires careful consideration.
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Affiliation(s)
- Irene Riz
- Department of Anatomy and Regenerative Biology, George Washington University, Washington, DC, USA
| | - Robert G Hawley
- Department of Anatomy and Regenerative Biology, George Washington University, Washington, DC, USA
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40
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Contributions of intestinal epithelial barriers to health and disease. Exp Cell Res 2017; 358:71-77. [PMID: 28342899 DOI: 10.1016/j.yexcr.2017.03.036] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 03/16/2017] [Indexed: 12/15/2022]
Abstract
A core function of epithelia is to form barriers that separate tissue compartments within complex organisms. These barriers also separate the internal milieu from the external environment and are, therefore, an essential component of host defense. However, in many cases, a perfect barrier would be improbable with life itself. Examples include the air spaces within the lungs, the renal tubules, and the intestines. Here, we focus on the mechanisms by which barriers are assembled, maintained, and regulated in the context of health and disease. Because of its unique challenges and extensive study, we focus on the gastrointestinal tract as an organ-specific example of the essential contributions of the paracellular barrier to life.
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41
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Sluysmans S, Vasileva E, Spadaro D, Shah J, Rouaud F, Citi S. The role of apical cell-cell junctions and associated cytoskeleton in mechanotransduction. Biol Cell 2017; 109:139-161. [PMID: 28220498 DOI: 10.1111/boc.201600075] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 02/09/2017] [Accepted: 02/13/2017] [Indexed: 01/13/2023]
Abstract
Tissues of multicellular organisms are characterised by several types of specialised cell-cell junctions. In vertebrate epithelia and endothelia, tight and adherens junctions (AJ) play critical roles in barrier and adhesion functions, and are connected to the actin and microtubule cytoskeletons. The interaction between junctions and the cytoskeleton is crucial for tissue development and physiology, and is involved in the molecular mechanisms governing cell shape, motility, growth and signalling. The machineries which functionally connect tight and AJ to the cytoskeleton comprise proteins which either bind directly to cytoskeletal filaments, or function as adaptors for regulators of the assembly and function of the cytoskeleton. In the last two decades, specific cytoskeleton-associated junctional molecules have been implicated in mechanotransduction, revealing the existence of multimolecular complexes that can sense mechanical cues and translate them into adaptation to tensile forces and biochemical signals. Here, we summarise the current knowledge about the machineries that link tight and AJ to actin filaments and microtubules, and the molecular basis for mechanotransduction at epithelial and endothelial AJ.
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Affiliation(s)
- Sophie Sluysmans
- Department of Cell Biology, Institute of Genomics and Genetics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Ekaterina Vasileva
- Department of Cell Biology, Institute of Genomics and Genetics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Domenica Spadaro
- Department of Cell Biology, Institute of Genomics and Genetics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Jimit Shah
- Department of Cell Biology, Institute of Genomics and Genetics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Florian Rouaud
- Department of Cell Biology, Institute of Genomics and Genetics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Sandra Citi
- Department of Cell Biology, Institute of Genomics and Genetics of Geneva (iGE3), University of Geneva, Geneva, Switzerland
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42
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Hofherr A, Busch T, Huber N, Nold A, Bohn A, Viau A, Bienaimé F, Kuehn EW, Arnold SJ, Köttgen M. Efficient genome editing of differentiated renal epithelial cells. Pflugers Arch 2016; 469:303-311. [PMID: 27987038 PMCID: PMC5222933 DOI: 10.1007/s00424-016-1924-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/27/2016] [Accepted: 11/29/2016] [Indexed: 12/18/2022]
Abstract
Recent advances in genome editing technologies have enabled the rapid and precise manipulation of genomes, including the targeted introduction, alteration, and removal of genomic sequences. However, respective methods have been described mainly in non-differentiated or haploid cell types. Genome editing of well-differentiated renal epithelial cells has been hampered by a range of technological issues, including optimal design, efficient expression of multiple genome editing constructs, attainable mutation rates, and best screening strategies. Here, we present an easily implementable workflow for the rapid generation of targeted heterozygous and homozygous genomic sequence alterations in renal cells using transcription activator-like effector nucleases (TALENs) and the clustered regularly interspaced short palindromic repeat (CRISPR) system. We demonstrate the versatility of established protocols by generating novel cellular models for studying autosomal dominant polycystic kidney disease (ADPKD). Furthermore, we show that cell culture-validated genetic modifications can be readily applied to mouse embryonic stem cells (mESCs) for the generation of corresponding mouse models. The described procedure for efficient genome editing can be applied to any cell type to study physiological and pathophysiological functions in the context of precisely engineered genotypes.
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Affiliation(s)
- Alexis Hofherr
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany. .,Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany. .,Faculty of Biology, University of Freiburg, Freiburg, Germany.
| | - Tilman Busch
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Nora Huber
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andreas Nold
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Albert Bohn
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Amandine Viau
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Frank Bienaimé
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - E Wolfgang Kuehn
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Sebastian J Arnold
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,BIOSS Centre of Biological Signalling Studies, Albert-Ludwigs-University, Freiburg, Germany
| | - Michael Köttgen
- Renal Division, Department of Medicine, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany.
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43
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Van Itallie CM, Tietgens AJ, Anderson JM. Visualizing the dynamic coupling of claudin strands to the actin cytoskeleton through ZO-1. Mol Biol Cell 2016; 28:524-534. [PMID: 27974639 PMCID: PMC5305259 DOI: 10.1091/mbc.e16-10-0698] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 11/28/2016] [Accepted: 12/09/2016] [Indexed: 01/27/2023] Open
Abstract
The organization and integrity of epithelial tight junctions depend on interactions between claudins, ZO scaffolding proteins, and the cytoskeleton. However, although binding between claudins and ZO-1/2/3 and between ZO-1/2/3 and numerous cytoskeletal proteins has been demonstrated in vitro, fluorescence recovery after photobleaching analysis suggests interactions in vivo are likely highly dynamic. Here we use superresolution live-cell imaging in a model fibroblast system to examine relationships between claudins, ZO-1, occludin, and actin. We find that GFP claudins make easily visualized dynamic strand patches between two fibroblasts; strand dynamics is constrained by ZO-1 binding. Claudin association with actin is also dependent on ZO-1, but colocalization demonstrates intermittent rather than continuous association between claudin, ZO-1, and actin. Independent of interaction with ZO-1 or actin, claudin strands break and reanneal; pulse-chase-pulse analysis using SNAP-tagged claudins showed preferential incorporation of newly synthesized claudins into break sites. Although claudin strand behavior in fibroblasts may not fully recapitulate that of epithelial tight junction strands, this is the first direct demonstration of the ability of ZO-1 to stabilize claudin strands. We speculate that intermittent tethering of claudins to actin may allow for accommodation of the paracellular seal to physiological or pathological alterations in cell shape or movement.
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Affiliation(s)
- Christina M Van Itallie
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Amber Jean Tietgens
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - James M Anderson
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
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44
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Ugalde-Silva P, Gonzalez-Lugo O, Navarro-Garcia F. Tight Junction Disruption Induced by Type 3 Secretion System Effectors Injected by Enteropathogenic and Enterohemorrhagic Escherichia coli. Front Cell Infect Microbiol 2016; 6:87. [PMID: 27606286 PMCID: PMC4995211 DOI: 10.3389/fcimb.2016.00087] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/10/2016] [Indexed: 12/18/2022] Open
Abstract
The intestinal epithelium consists of a single cell layer, which is a critical selectively permeable barrier to both absorb nutrients and avoid the entry of potentially harmful entities, including microorganisms. Epithelial cells are held together by the apical junctional complexes, consisting of adherens junctions, and tight junctions (TJs), and by underlying desmosomes. TJs lay in the apical domain of epithelial cells and are mainly composed by transmembrane proteins such as occludin, claudins, JAMs, and tricellulin, that are associated with the cytoplasmic plaque formed by proteins from the MAGUK family, such as ZO-1/2/3, connecting TJ to the actin cytoskeleton, and cingulin and paracingulin connecting TJ to the microtubule network. Extracellular bacteria such as EPEC and EHEC living in the intestinal lumen inject effectors proteins directly from the bacterial cytoplasm to the host cell cytoplasm, where they play a relevant role in the manipulation of the eukaryotic cell functions by modifying or blocking cell signaling pathways. TJ integrity depends on various cell functions such as actin cytoskeleton, microtubule network for vesicular trafficking, membrane integrity, inflammation, and cell survival. EPEC and EHEC effectors target most of these functions. Effectors encoded inside or outside of locus of enterocyte effacement (LEE) disrupt the TJ strands. EPEC and EHEC exploit the TJ dynamics to open this structure, for causing diarrhea. EPEC and EHEC secrete effectors that mimic host proteins to manipulate the signaling pathways, including those related to TJ dynamics. In this review, we focus on the known mechanisms exploited by EPEC and EHEC effectors for causing TJ disruption.
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Affiliation(s)
- Paul Ugalde-Silva
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional México City, Mexico
| | - Octavio Gonzalez-Lugo
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional México City, Mexico
| | - Fernando Navarro-Garcia
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional México City, Mexico
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45
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Campos Y, Qiu X, Gomero E, Wakefield R, Horner L, Brutkowski W, Han YG, Solecki D, Frase S, Bongiovanni A, d'Azzo A. Alix-mediated assembly of the actomyosin-tight junction polarity complex preserves epithelial polarity and epithelial barrier. Nat Commun 2016; 7:11876. [PMID: 27336173 PMCID: PMC4931029 DOI: 10.1038/ncomms11876] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 05/09/2016] [Indexed: 02/07/2023] Open
Abstract
Maintenance of epithelial cell polarity and epithelial barrier relies on the spatial organization of the actin cytoskeleton and proper positioning/assembly of intercellular junctions. However, how these processes are regulated is poorly understood. Here we reveal a key role for the multifunctional protein Alix in both processes. In a knockout mouse model of Alix, we identified overt structural changes in the epithelium of the choroid plexus and in the ependyma, such as asymmetrical cell shape and size, misplacement and abnormal beating of cilia, blebbing of the microvilli. These defects culminate in excessive cell extrusion, enlargement of the lateral ventricles and hydrocephalus. Mechanistically, we find that by interacting with F-actin, the Par complex and ZO-1, Alix ensures the formation and maintenance of the apically restricted actomyosin-tight junction complex. We propose that in this capacity Alix plays a role in the establishment of apical-basal polarity and in the maintenance of the epithelial barrier.
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Affiliation(s)
- Yvan Campos
- Department of Genetics, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Xiaohui Qiu
- Department of Genetics, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Elida Gomero
- Department of Genetics, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Randall Wakefield
- Cellular Imaging Shared Resource, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Linda Horner
- Cellular Imaging Shared Resource, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Wojciech Brutkowski
- Laboratory of Imaging Tissue Structure and Function, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland
| | - Young-Goo Han
- Department of Developmental Neurobiology, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - David Solecki
- Department of Developmental Neurobiology, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Sharon Frase
- Cellular Imaging Shared Resource, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
| | - Antonella Bongiovanni
- Institute of Biomedicine and Molecular Immunology, National Research Council, 90146 Palermo, Italy
| | - Alessandra d'Azzo
- Department of Genetics, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, USA
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46
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Watson JR, Fox HM, Nietlispach D, Gallop JL, Owen D, Mott HR. Investigation of the Interaction between Cdc42 and Its Effector TOCA1: HANDOVER OF Cdc42 TO THE ACTIN REGULATOR N-WASP IS FACILITATED BY DIFFERENTIAL BINDING AFFINITIES. J Biol Chem 2016; 291:13875-90. [PMID: 27129201 PMCID: PMC4919469 DOI: 10.1074/jbc.m116.724294] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Indexed: 11/23/2022] Open
Abstract
Transducer of Cdc42-dependent actin assembly protein 1 (TOCA1) is an effector of the Rho family small G protein Cdc42. It contains a membrane-deforming F-BAR domain as well as a Src homology 3 (SH3) domain and a G protein-binding homology region 1 (HR1) domain. TOCA1 binding to Cdc42 leads to actin rearrangements, which are thought to be involved in processes such as endocytosis, filopodia formation, and cell migration. We have solved the structure of the HR1 domain of TOCA1, providing the first structural data for this protein. We have found that the TOCA1 HR1, like the closely related CIP4 HR1, has interesting structural features that are not observed in other HR1 domains. We have also investigated the binding of the TOCA HR1 domain to Cdc42 and the potential ternary complex between Cdc42 and the G protein-binding regions of TOCA1 and a member of the Wiskott-Aldrich syndrome protein family, N-WASP. TOCA1 binds Cdc42 with micromolar affinity, in contrast to the nanomolar affinity of the N-WASP G protein-binding region for Cdc42. NMR experiments show that the Cdc42-binding domain from N-WASP is able to displace TOCA1 HR1 from Cdc42, whereas the N-WASP domain but not the TOCA1 HR1 domain inhibits actin polymerization. This suggests that TOCA1 binding to Cdc42 is an early step in the Cdc42-dependent pathways that govern actin dynamics, and the differential binding affinities of the effectors facilitate a handover from TOCA1 to N-WASP, which can then drive recruitment of the actin-modifying machinery.
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Affiliation(s)
- Joanna R Watson
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
| | - Helen M Fox
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and the Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, United Kingdom
| | - Daniel Nietlispach
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
| | - Jennifer L Gallop
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and the Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, United Kingdom
| | - Darerca Owen
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
| | - Helen R Mott
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
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Stamatovic SM, Johnson AM, Keep RF, Andjelkovic AV. Junctional proteins of the blood-brain barrier: New insights into function and dysfunction. Tissue Barriers 2016; 4:e1154641. [PMID: 27141427 DOI: 10.1080/21688370.2016.1154641] [Citation(s) in RCA: 234] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 02/08/2016] [Accepted: 02/09/2016] [Indexed: 01/05/2023] Open
Abstract
The blood-brain barrier (BBB) is a highly complex and dynamic barrier. It is formed by an interdependent network of brain capillary endothelial cells, endowed with barrier properties, and perivascular cells (astrocytes and pericytes) responsible for inducing and maintaining those properties. One of the primary properties of the BBB is a strict regulation of paracellular permeability due to the presence of junctional complexes (tight, adherens and gap junctions) between the endothelial cells. Alterations in junction assembly and function significantly affect BBB properties, particularly barrier permeability. However, such alterations are also involved in remodeling the brain endothelial cell surface and regulating brain endothelial cell phenotype. This review summarizes the characteristics of brain endothelial tight, adherens and gap junctions and highlights structural and functional alterations in junctional proteins that may contribute to BBB dysfunction.
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Affiliation(s)
| | - Allison M Johnson
- Department of Pathology; University of Michigan Medical School ; Ann Arbor, MI USA
| | - Richard F Keep
- Department of Neurosurgery; University of Michigan Medical School; Ann Arbor, MI USA; Molecular and Integrative Physiology, University of Michigan Medical School; Ann Arbor, MI USA
| | - Anuska V Andjelkovic
- Department of Pathology; University of Michigan Medical School; Ann Arbor, MI USA; Department of Neurosurgery; University of Michigan Medical School; Ann Arbor, MI USA
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