1
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Büyücek S, Viehweger F, Reiswich V, Gorbokon N, Chirico V, Bernreuther C, Lutz F, Kind S, Schlichter R, Weidemann S, Clauditz TS, Hinsch A, Bawahab AA, Jacobsen F, Luebke AM, Dum D, Hube-Magg C, Kluth M, Möller K, Menz A, Marx AH, Krech T, Lebok P, Fraune C, Sauter G, Simon R, Burandt E, Minner S, Steurer S, Lennartz M, Freytag M. Reduced occludin expression is related to unfavorable tumor phenotype and poor prognosis in many different tumor types: A tissue microarray study on 16,870 tumors. PLoS One 2025; 20:e0321105. [PMID: 40173205 PMCID: PMC11964279 DOI: 10.1371/journal.pone.0321105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2024] [Accepted: 03/01/2025] [Indexed: 04/04/2025] Open
Abstract
Occludin is a key component of tight junctions. Reduced occludin expression has been linked to cancer progression in individual tumor types, but a comprehensive and standardized analysis across human tumor types is lacking. To study the prevalence and clinical relevance of occludin expression in cancer, a tissue microarray containing 16,870 samples from 148 different tumor types and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. Occludin immunostaining was observed in 10,746 (76.6%) of 14,017 analyzable tumors, including 18.9% with weak, 16.2% with moderate, and 41.6% with strong staining intensity. Occludin positivity was found in 134 of 148 tumor categories and was most frequent in adenocarcinomas (37.5-100%) and neuroendocrine neoplasms (67.9-100%), less common in squamous cell carcinomas (23.8-93%) and in malignant mesotheliomas (up to 48.1%), and rare in Non-Hodgkin's lymphomas (1-2%) and most mesenchymal tumors. Reduced occludin staining was linked to adverse tumor features in several tumor types, including colorectal adenocarcinoma (advanced pT stage, p < 0.0001; L1 status, p = 0.0384; absence of microsatellite instability, p < 0.0001), pancreatic adenocarcinoma (advanced pT stage, p = 0.005), clear cell renal cell carcinoma (high ISUP grade, p < 0.0001; advanced pT stage, p < 0.0001; high UICC stage, p < 0.0001; distant metastasis, p = 0.0422; shortened overall or recurrence-free survival, p ≤ 0.0116), papillary renal cell carcinoma (high pT stage, p < 0.0001; high UICC stage, p = 0.0228; distant metastasis, p = 0.0338; shortened recurrence-free survival, p = 0.006), and serous high-grade ovarian cancer (advanced pT stage, p = 0.0133). Occludin staining was unrelated to parameters of tumor aggressiveness in breast, gastric, endometrial, and thyroidal cancer. Our data demonstrate significant levels of occludin expression in many different tumor entities and identify reduced occludin expression as a potentially useful prognostic feature in several tumor entities.
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Affiliation(s)
- Seyma Büyücek
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Florian Viehweger
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Viktor Reiswich
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Natalia Gorbokon
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Viktoria Chirico
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Bernreuther
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Florian Lutz
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Simon Kind
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ria Schlichter
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sören Weidemann
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Till S. Clauditz
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Andrea Hinsch
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Frank Jacobsen
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Pathology-Hamburg, Labor Lademannbogen MVZ GmbH, Hamburg, Germany
| | - Andreas M. Luebke
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - David Dum
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Claudia Hube-Magg
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Martina Kluth
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Katharina Möller
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anne Menz
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Andreas H. Marx
- Department of Pathology, Academic Hospital Fuerth, Fuerth Germany
| | - Till Krech
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Pathology, Clinical Center Osnabrueck, Osnabrueck, Germany
| | - Patrick Lebok
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Pathology, Clinical Center Osnabrueck, Osnabrueck, Germany
| | - Christoph Fraune
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Pathology, Clinical Center Osnabrueck, Osnabrueck, Germany
| | - Guido Sauter
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ronald Simon
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Eike Burandt
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sarah Minner
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan Steurer
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Maximilian Lennartz
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Morton Freytag
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Zhang L, Wei X. The Lego hypothesis of tissue morphogenesis: stereotypic organization of parallel orientational cell adhesions for epithelial self-assembly. Biol Rev Camb Philos Soc 2025; 100:445-460. [PMID: 39308450 PMCID: PMC11718597 DOI: 10.1111/brv.13147] [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: 01/13/2024] [Revised: 09/06/2024] [Accepted: 09/10/2024] [Indexed: 01/11/2025]
Abstract
How tissues develop distinct structures remains poorly understood. We propose herein the Lego hypothesis of tissue morphogenesis, which states that during tissue morphogenesis, the topographical properties of cell surface adhesion molecules can be dynamically altered and polarised by regulating the spatiotemporal expression and localization of orientational cell adhesion (OCA) molecules cell-autonomously and non-cell-autonomously, thus modulating cells into unique Lego pieces for self-assembling into distinct cytoarchitectures. This concept can be exemplified by epithelial morphogenesis, in which cells are coalesced into a sheet by many types of adhesions. Among them, parallel OCAs (pOCAs) at the lateral cell membranes are essential for configuring cells in parallel. Major pOCAs include Na+/K+-ATPase-mediated adhesions, Crumbs-mediated adhesions, tight junctions, adherens junctions, and desmosomes. These pOCAs align in stereotypical orders along the apical-to-basal axis, and their absolute positioning is also regulated. Such spatial organization of pOCAs underlies proper epithelial morphogenesis. Thus, a key open question about tissue morphogenesis is how to regulate OCAs to make compatible adhesive cellular Lego pieces for tissue construction.
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Affiliation(s)
- Lili Zhang
- Department of PsychologyDalian Medical University9 Lvshun South Road WestDalian116044Liaoning ProvinceChina
| | - Xiangyun Wei
- Departments of Ophthalmology and Microbiology & Molecular GeneticsUniversity of Pittsburgh1622 Locust StreetPittsburgh15219PAUSA
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3
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Zhang L, Wen X, Chen X, Zhou Y, Wang K, Zhu Y. GhCASPL1 regulates secondary cell wall thickening in cotton fibers by stabilizing the cellulose synthase complex on the plasma membrane. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024; 66:2632-2647. [PMID: 39315818 PMCID: PMC11622535 DOI: 10.1111/jipb.13777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 08/26/2024] [Accepted: 08/30/2024] [Indexed: 09/25/2024]
Abstract
Cotton (Gossypium hirsutum) fibers are elongated single cells that rapidly accumulate cellulose during secondary cell wall (SCW) thickening, which requires cellulose synthase complex (CSC) activity. Here, we describe the CSC-interacting factor CASPARIAN STRIP MEMBRANE DOMAIN-LIKE1 (GhCASPL1), which contributes to SCW thickening by influencing CSC stability on the plasma membrane. GhCASPL1 is preferentially expressed in fiber cells during SCW biosynthesis and encodes a MARVEL domain protein. The ghcaspl1 ghcaspl2 mutant exhibited reduced plant height and produced mature fibers with fewer natural twists, lower tensile strength, and a thinner SCW compared to the wild type. Similarly, the Arabidopsis (Arabidopsis thaliana) caspl1 caspl2 double mutant showed a lower cellulose content and thinner cell walls in the stem vasculature than the wild type but normal plant morphology. Introducing the cotton gene GhCASPL1 successfully restored the reduced cellulose content of the Arabidopsis caspl1 caspl2 mutant. Detergent treatments, ultracentrifugation assays, and enzymatic assays showed that the CSC in the ghcaspl1 ghcaspl2 double mutant showed reduced membrane binding and decreased enzyme activity compared to the wild type. GhCASPL1 binds strongly to phosphatidic acid (PA), which is present in much higher amounts in thickening fiber cells compared to ovules and leaves. Mutating the PA-binding site in GhCASPL1 resulted in the loss of its colocalization with GhCesA8, and it failed to localize to the plasma membrane. PA may alter membrane structure to facilitate protein-protein interactions, suggesting that GhCASPL1 and PA collaboratively stabilize the CSC. Our findings shed light on CASPL functions and the molecular machinery behind SCW biosynthesis in cotton fibers.
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Affiliation(s)
- Li Zhang
- Institute for Advanced StudiesWuhan UniversityWuhan430072China
| | - Xingpeng Wen
- Institute for Advanced StudiesWuhan UniversityWuhan430072China
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life SciencesWuhan UniversityWuhan430072China
- TaiKang Center for Life and Medical SciencesWuhan UniversityWuhan430072China
| | - Xin Chen
- State Key Laboratory of Protein and Plant Gene Research, College of Life SciencesPeking UniversityBeijing100871China
| | - Yifan Zhou
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life SciencesWuhan UniversityWuhan430072China
| | - Kun Wang
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life SciencesWuhan UniversityWuhan430072China
| | - Yuxian Zhu
- Institute for Advanced StudiesWuhan UniversityWuhan430072China
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life SciencesWuhan UniversityWuhan430072China
- TaiKang Center for Life and Medical SciencesWuhan UniversityWuhan430072China
- State Key Laboratory of Protein and Plant Gene Research, College of Life SciencesPeking UniversityBeijing100871China
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4
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Kageler L, Perr J, Flynn RA. Tools to investigate the cell surface: Proximity as a central concept in glycoRNA biology. Cell Chem Biol 2024; 31:1132-1144. [PMID: 38772372 PMCID: PMC11193615 DOI: 10.1016/j.chembiol.2024.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 04/02/2024] [Accepted: 04/25/2024] [Indexed: 05/23/2024]
Abstract
Proximity is a fundamental concept in chemistry and biology, referring to the convergence of molecules to facilitate new molecular interactions or reactions. Hybrid biopolymers like glycosylphosphatidylinositol (GPI)-anchored proteins, ubiquitinated proteins, glycosylated RNAs (glycoRNAs), and RNAylated proteins exemplify this by covalent bonding of moieties that are often orthogonally active. Hybrid molecules like glycoRNAs are localized to new physical spaces, generating new interfaces for biological functions. To fully investigate the compositional and spatial features of molecules like glycoRNAs, flexible genetic and chemical tools that encompass different encoding and targeting biopolymers are required. Here we discuss concepts of molecular proximity and explore newer proximity labeling technologies that facilitate applications in RNA biology, cell surface biology, and the interface therein with a particular focus on glycoRNA biology. We review the advantages and disadvantages of methods pertaining to cell surface RNA identification and provide insights into the vast opportunities for method development in this area.
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Affiliation(s)
- Lauren Kageler
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, USA
| | - Jonathan Perr
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, USA
| | - Ryan A Flynn
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, USA; Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.
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5
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Dithmer S, Blasig IE, Fraser PA, Qin Z, Haseloff RF. The Basic Requirement of Tight Junction Proteins in Blood-Brain Barrier Function and Their Role in Pathologies. Int J Mol Sci 2024; 25:5601. [PMID: 38891789 PMCID: PMC11172262 DOI: 10.3390/ijms25115601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/10/2024] [Accepted: 03/28/2024] [Indexed: 06/21/2024] Open
Abstract
This review addresses the role of tight junction proteins at the blood-brain barrier (BBB). Their expression is described, and their role in physiological and pathological processes at the BBB is discussed. Based on this, new approaches are depicted for paracellular drug delivery and diagnostics in the treatment of cerebral diseases. Recent data provide convincing evidence that, in addition to its impairment in the course of diseases, the BBB could be involved in the aetiology of CNS disorders. Further progress will be expected based on new insights in tight junction protein structure and in their involvement in signalling pathways.
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Affiliation(s)
- Sophie Dithmer
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany (I.E.B.)
| | - Ingolf E. Blasig
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany (I.E.B.)
| | | | - Zhihai Qin
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100049, China
| | - Reiner F. Haseloff
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany (I.E.B.)
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6
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Torices S, Daire L, Simon S, Naranjo O, Mendoza L, Teglas T, Fattakhov N, Adesse D, Toborek M. Occludin: a gatekeeper of brain Infection by HIV-1. Fluids Barriers CNS 2023; 20:73. [PMID: 37840143 PMCID: PMC10577960 DOI: 10.1186/s12987-023-00476-7] [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: 08/05/2023] [Accepted: 10/09/2023] [Indexed: 10/17/2023] Open
Abstract
Compromised structure and function of the blood-brain barrier (BBB) is one of the pathological hallmarks of brain infection by HIV-1. BBB damage during HIV-1 infection has been associated with modified expression of tight junction (TJ) proteins, including occludin. Recent evidence indicated occludin as a redox-sensitive, multifunctional protein that can act as both an NADH oxidase and influence cellular metabolism through AMPK kinase. One of the newly identified functions of occludin is its involvement in regulating HIV-1 infection. Studies suggest that occludin expression levels and the rate of HIV-1 infection share a reverse, bidirectional relationship; however, the mechanisms of this relationship are unclear. In this review, we describe the pathways involved in the regulation of HIV-1 infection by occludin. We propose that occludin may serve as a potential therapeutic target to control HIV-1 infection and to improve the lives of people living with HIV-1.
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Affiliation(s)
- Silvia Torices
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Leah Daire
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Sierra Simon
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Oandy Naranjo
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Luisa Mendoza
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Timea Teglas
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Nikolai Fattakhov
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
| | - Daniel Adesse
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
| | - Michal Toborek
- Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, 528E Gautier Bldg. 1011 NW 15th Street Miami, Miami, FL, 11336, USA.
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7
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Wangsanut T, Amsri A, Pongpom M. Antibody screening reveals antigenic proteins involved in Talaromyces marneffei and human interaction. Front Cell Infect Microbiol 2023; 13:1118979. [PMID: 37404721 PMCID: PMC10315666 DOI: 10.3389/fcimb.2023.1118979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 05/30/2023] [Indexed: 07/06/2023] Open
Abstract
Talaromycosis is a fungal infection that generally affects immunocompromised hosts and is one of the most frequent systemic mycoses in HIV patients, especially in endemic areas such as Southeast Asia. Talaromyces marneffei, the causative agent of talaromycosis, grows as a mold in the environment but adapts to the human body and host niches by transitioning from conidia to yeast-like cells. Knowledge of the human host and T. marneffei interaction has a direct impact on the diagnosis, yet studies are still lacking. The morbidity and mortality rates are high in taloromycosis patients if the diagnosis and treatments are delayed. Immunogenic proteins are excellent candidates for developing detection tools. Previously, we identified antigenic proteins that were recognized by antibodies from talaromycosis sera. Three of these identified proteins have been previously characterized in detail, while the others have not been explored. To expedite the progress of antigen discovery, the complete list of antigenic proteins and their features was fully reported in this study. Functional annotation and Gene Ontology examination revealed that these proteins showed a high association with membrane trafficking. Further bioinformatics analyses were performed to search for antigenic protein characteristics, including functional domains, critical residues, subcellular localization, secretory signals, and epitope peptide sequences. Expression profiling of these antigenic encoding genes was investigated using quantitative real-time PCR. The results demonstrated that most genes were expressed at low levels in the mold form, but were highly upregulated in the pathogenic yeast phase, consistent with the antigenic role of these genes during the human-host interaction. Most transcripts accumulated in the conidia, suggesting a role during phase transition. The collection of all antigen-encoding DNA sequences described here is freely accessible at GenBank, which could be useful for the research community to develop into biomarkers, diagnostic tests, research detection tools, and even vaccines.
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8
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Gao X, Yang Q, Zhang S, Huang X, Yan Z, Wang P, Gun S. LncRNA ALDB-898 modulates intestinal epithelial cell damage caused by Clostridium perfringens type C in piglet by regulating ssc-miR-122-5p/OCLN signaling. Mol Immunol 2022; 149:143-156. [PMID: 35834877 DOI: 10.1016/j.molimm.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 07/06/2022] [Accepted: 07/06/2022] [Indexed: 11/18/2022]
Abstract
Diarrhea of piglets caused by Clostridium perfringens type C (C. perfringens type C) infection is a global problem afflicting piglet production. Long noncoding RNA (LncRNA) and microRNA (miRNA) have emerged as critical regulators of this pathological process, but the underlying molecular mechanisms remain unclear. In this study, we first observed the expression changes of ALDBSSCG0000000898 (ALDB-898) and ssc-miR-122-5p in infected ileum tissue of piglets with C. perfringens type C, and then used C. perfringens beta2 toxin (CPB2) to induce intestinal porcine epithelial cells (IPEC-J2) to construct an injury model. Cytometry kit 8 (CCK-8), lactate dehydrogenase (LDH), real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, flow cytometry and fluorescein isothiocyanate-dextran 4 (FITC-Dextran 4) flux assays were performed to study the effect of ALDB-898 and ssc-miR-122-5p in apoptosis, inflammation and intestinal barrier damage and inflammatory in IPEC-J2 cells induced by CPB2. In addition, dual-luciferase reporter gene analysis was performed to confirm the relationship between ssc-miR-122-5p and ALDB-898 or ssc-miR-122-5p and occludin (OCLN), respectively. There were lower expression levels of ALDB-898 and OCLN and higher expression levels of ssc-miR-122-5p in diarrhea piglets caused by Clostridium perfringens type C. ALDB-898 and OCLN were significantly decreased and ssc-miR-122-5p was increased in IPEC-J2 after exposure to the CPB2 in a dose- and time-dependent manner. ALDB-898 overexpression mitigated CPB2-induced cell injury by promoting viability, restraining apoptosis, cytotoxicity, and inflammatory response, as well as weakening the destruction of the intestinal barrier. Further mechanisms disclosed that ALDB-898 functioned as a competing endogenous RNA (ceRNA) via binding to ssc-miR-122-5p, and OCLN was a target of ssc-miR-122-5p. Importantly, the ssc-miR-122-5p mimic led to abolishing the protective function of ALDB-898 on CPB2-induced IPEC-J2 cell damage, and the addition of OCLN reversed the negative impact of ssc-miR-122-5p, thereby restoring the protection of ALDB-898. Our data showed that ALDB-898 could enhance the expression of OCLN through competitive binding ssc-miR-122-5p to suppress CPB2-induced damage. The ALDB-898/ssc-miR-122-5p/OCLN signaling may be a candidate therapeutic pathway for diarrhea of piglets.
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Affiliation(s)
- Xiaoli Gao
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Qiaoli Yang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Shengwei Zhang
- Farmer Education and Training Work Station of Gansu Province, Lanzhou 730030, China
| | - Xiaoyu Huang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Zunqiang Yan
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Pengfei Wang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
| | - Shuangbao Gun
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China; Gansu Research Center for Swine Production Engineering and Technology, Lanzhou 730070, China.
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9
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Rubio-Ramos A, Bernabé-Rubio M, Labat-de-Hoz L, Casares-Arias J, Kremer L, Correas I, Alonso MA. MALL, a membrane-tetra-spanning proteolipid overexpressed in cancer, is present in membraneless nuclear biomolecular condensates. Cell Mol Life Sci 2022; 79:236. [PMID: 35399121 PMCID: PMC8995265 DOI: 10.1007/s00018-022-04270-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/08/2022] [Accepted: 03/22/2022] [Indexed: 12/04/2022]
Abstract
Proteolipids are proteins with unusual lipid-like properties. It has long been established that PLP and plasmolipin, which are two unrelated membrane-tetra-spanning myelin proteolipids, can be converted in vitro into a water-soluble form with a distinct conformation, raising the question of whether these, or other similar proteolipids, can adopt two different conformations in the cell to adapt their structure to distinct environments. Here, we show that MALL, another proteolipid with a membrane-tetra-spanning structure, distributes in membranes outside the nucleus and, within the nucleus, in membrane-less, liquid-like PML body biomolecular condensates. Detection of MALL in one or other environment was strictly dependent on the method of cell fixation used, suggesting that MALL adopts different conformations depending on its physical environment —lipidic or aqueous— in the cell. The acquisition of the condensate-compatible conformation requires PML expression. Excess MALL perturbed the distribution of the inner nuclear membrane proteins emerin and LAP2β, and that of the DNA-binding protein BAF, leading to the formation of aberrant nuclei. This effect, which is consistent with studies identifying overexpressed MALL as an unfavorable prognostic factor in cancer, could contribute to cell malignancy. Our study establishes a link between proteolipids, membranes and biomolecular condensates, with potential biomedical implications.
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Affiliation(s)
- Armando Rubio-Ramos
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Miguel Bernabé-Rubio
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Leticia Labat-de-Hoz
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Javier Casares-Arias
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Leonor Kremer
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain
| | - Isabel Correas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
- Department of Molecular Biology, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Miguel A Alonso
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
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10
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Shulgin AA, Lebedev TD, Prassolov VS, Spirin PV. Plasmolipin and Its Role in Cell Processes. Mol Biol 2021; 55:773-785. [PMID: 34955555 PMCID: PMC8682038 DOI: 10.1134/s0026893321050113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/26/2021] [Accepted: 04/05/2021] [Indexed: 12/04/2022]
Abstract
The mechanisms involved in the origin and development of malignant and neurodegenerative diseases are an important area of modern biomedicine. A crucial task is to identify new molecular markers that are associated with rearrangements of intracellular signaling and can be used for prognosis and the development of effective treatment approaches. The proteolipid plasmolipin (PLLP) is a possible marker. PLLP is a main component of the myelin sheath and plays an important role in the development and normal function of the nervous system. PLLP is involved in intracellular transport, lipid raft formation, and Notch signaling. PLLP is presumably involved in various disorders, such as cancer, schizophrenia, Alzheimer's disease, and type 2 diabetes mellitus. PLLP and its homologs were identified as possible virus entry receptors. The review summarizes the data on the PLLP structure, normal functions, and role in diseases.
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Affiliation(s)
- A. A. Shulgin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Moscow Institute of Physics and Technology (State University), 141701 Dolgoprudny, Moscow oblast Russia
| | - T. D. Lebedev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - V. S. Prassolov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - P. V. Spirin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
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11
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Heymans C, Delcorte O, Spourquet C, Villacorte-Tabelin M, Dupasquier S, Achouri Y, Mahibullah S, Lemoine P, Balda MS, Matter K, Pierreux CE. Spatio-temporal expression pattern and role of the tight junction protein MarvelD3 in pancreas development and function. Sci Rep 2021; 11:14519. [PMID: 34267243 PMCID: PMC8282860 DOI: 10.1038/s41598-021-93654-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/23/2021] [Indexed: 11/29/2022] Open
Abstract
Tight junction complexes are involved in the establishment and maintenance of cell polarity and the regulation of signalling pathways, controlling biological processes such as cell differentiation and cell proliferation. MarvelD3 is a tight junction protein expressed in adult epithelial and endothelial cells. In Xenopus laevis, MarvelD3 morphants present differentiation defects of several ectodermal derivatives. In vitro experiments further revealed that MarvelD3 couples tight junctions to the MEKK1-JNK pathway to regulate cell behaviour and survival. In this work, we found that MarvelD3 is expressed from early developmental stages in the exocrine and endocrine compartments of the pancreas, as well as in endothelial cells of this organ. We thoroughly characterized MarvelD3 expression pattern in developing pancreas and evaluated its function by genetic ablation. Surprisingly, inactivation of MarvelD3 in mice did not alter development and differentiation of the pancreatic tissue. Moreover, tight junction formation and organization, cell polarization, and activity of the JNK-pathway were not impacted by the deletion of MarvelD3.
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Affiliation(s)
| | - Ophélie Delcorte
- Cell Biology Unit, de Duve Institute, UCLouvain, Woluwe, Belgium
| | | | - Mylah Villacorte-Tabelin
- Cell Biology Unit, de Duve Institute, UCLouvain, Woluwe, Belgium
- PRISM, MSU-IIT, Iligan City, Philippines
| | | | | | - Siam Mahibullah
- Cell Biology Unit, de Duve Institute, UCLouvain, Woluwe, Belgium
| | - Pascale Lemoine
- Cell Biology Unit, de Duve Institute, UCLouvain, Woluwe, Belgium
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12
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Shimizu Y, Shinoda T, Shirasago Y, Kondoh M, Shinya N, Hanada K, Yagi K, Suzuki T, Wakita T, Kimura-Someya T, Shirouzu M, Fukasawa M. Occludin-binding single-chain variable fragment and antigen-binding fragment antibodies prevent hepatitis C virus infection. FEBS Lett 2020; 595:220-229. [PMID: 33113151 DOI: 10.1002/1873-3468.13975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/23/2020] [Accepted: 10/09/2020] [Indexed: 11/07/2022]
Abstract
Occludin (OCLN) is a tetraspan membrane component of epithelial tight junctions and a known receptor for hepatitis C virus (HCV). Previously, we established functional monoclonal antibodies (mAbs) that bind to each extracellular loop of OCLN and showed their ability to prevent in vitro and in vivo HCV infection. In this study, we converted these mAbs to corresponding monovalent antigen-binding fragments (Fabs) and single-chain variable fragment (scFv) antibodies. These Fab fragments and scFv antibodies demonstrate similar binding specificity and affinity to parental anti-OCLN mAbs. Moreover, Fab fragments and scFv antibodies inhibit in vitro HCV infection. The small functional monovalent OCLN-binding probes reported in our study have high potential as drug candidates and tools for biological and pharmaceutical studies of OCLN.
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Affiliation(s)
- Yoshimi Shimizu
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan.,Department of Pharmaceutical Sciences, Teikyo Heisei University, Nakano-ku, Japan
| | - Takehiro Shinoda
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Japan
| | - Yoshitaka Shirasago
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Masuo Kondoh
- Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan
| | - Naoko Shinya
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Kiyohito Yagi
- Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan
| | - Tetsuro Suzuki
- Department of Infectious Diseases, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Tomomi Kimura-Someya
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Japan
| | - Mikako Shirouzu
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Japan
| | - Masayoshi Fukasawa
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
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13
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Lochhead JJ, Yang J, Ronaldson PT, Davis TP. Structure, Function, and Regulation of the Blood-Brain Barrier Tight Junction in Central Nervous System Disorders. Front Physiol 2020; 11:914. [PMID: 32848858 PMCID: PMC7424030 DOI: 10.3389/fphys.2020.00914] [Citation(s) in RCA: 237] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 07/08/2020] [Indexed: 12/16/2022] Open
Abstract
The blood-brain barrier (BBB) allows the brain to selectively import nutrients and energy critical to neuronal function while simultaneously excluding neurotoxic substances from the peripheral circulation. In contrast to the highly permeable vasculature present in most organs that reside outside of the central nervous system (CNS), the BBB exhibits a high transendothelial electrical resistance (TEER) along with a low rate of transcytosis and greatly restricted paracellular permeability. The property of low paracellular permeability is controlled by tight junction (TJ) protein complexes that seal the paracellular route between apposing brain microvascular endothelial cells. Although tight junction protein complexes are principal contributors to physical barrier properties, they are not static in nature. Rather, tight junction protein complexes are highly dynamic structures, where expression and/or localization of individual constituent proteins can be modified in response to pathophysiological stressors. These stressors induce modifications to tight junction protein complexes that involve de novo synthesis of new protein or discrete trafficking mechanisms. Such responsiveness of BBB tight junctions to diseases indicates that these protein complexes are critical for maintenance of CNS homeostasis. In fulfillment of this vital role, BBB tight junctions are also a major obstacle to therapeutic drug delivery to the brain. There is an opportunity to overcome this substantial obstacle and optimize neuropharmacology via acquisition of a detailed understanding of BBB tight junction structure, function, and regulation. In this review, we discuss physiological characteristics of tight junction protein complexes and how these properties regulate delivery of therapeutics to the CNS for treatment of neurological diseases. Specifically, we will discuss modulation of tight junction structure, function, and regulation both in the context of disease states and in the setting of pharmacotherapy. In particular, we will highlight how these properties can be potentially manipulated at the molecular level to increase CNS drug levels via paracellular transport to the brain.
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14
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Castello-Serrano I, Lorent JH, Ippolito R, Levental KR, Levental I. Myelin-Associated MAL and PLP Are Unusual among Multipass Transmembrane Proteins in Preferring Ordered Membrane Domains. J Phys Chem B 2020; 124:5930-5939. [PMID: 32436385 PMCID: PMC7792449 DOI: 10.1021/acs.jpcb.0c03028] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Eukaryotic membranes can be partitioned into lipid-driven membrane microdomains called lipid rafts, which function to sort lipids and proteins in the plane of the membrane. As protein selectivity underlies all functions of lipid rafts, there has been significant interest in understanding the structural and molecular determinants of raft affinity. Such determinants have been described for lipids and single-spanning transmembrane proteins; however, how multipass transmembrane proteins (TMPs) partition between ordered and disordered phases has not been widely explored. Here we used cell-derived giant plasma membrane vesicles (GPMVs) to systematically measure multipass TMP partitioning to ordered membrane domains. Across a set of 24 structurally and functionally diverse multipass TMPs, the large majority (92%) had minimal raft affinity. The only exceptions were two myelin-associated four-pass TMPs, myelin and lymphocyte protein (MAL), and proteo lipid protein (PLP). We characterized the potential mechanisms for their exceptional raft affinity and observed that PLP requires cholesterol and sphingolipids for optimal association with ordered membrane domains and that PLP and MAL appear to compete for cholesterol-mediated raft affinity. These observations suggest broad conclusions about the composition of ordered membrane domains in cells and point to previously unrecognized drivers of raft affinity for multipass transmembrane proteins.
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Affiliation(s)
- Ivan Castello-Serrano
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Joseph H Lorent
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Rossana Ippolito
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Kandice R Levental
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Ilya Levental
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
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15
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Mailly L, Baumert TF. Hepatitis C virus infection and tight junction proteins: The ties that bind. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183296. [PMID: 32268133 DOI: 10.1016/j.bbamem.2020.183296] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/25/2020] [Accepted: 03/28/2020] [Indexed: 02/07/2023]
Abstract
The hepatitis C virus (HCV) is a major cause of liver diseases ranging from liver inflammation to advanced liver diseases like cirrhosis and hepatocellular carcinoma (HCC). HCV infection is restricted to the liver, and more specifically to hepatocytes, which represent around 80% of liver cells. The mechanism of HCV entry in human hepatocytes has been extensively investigated since the discovery of the virus 30 years ago. The entry mechanism is a multi-step process relying on several host factors including heparan sulfate proteoglycan (HSPG), low density lipoprotein receptor (LDLR), tetraspanin CD81, Scavenger Receptor class B type I (SR-BI), Epidermal Growth Factor Receptor (EGFR) and Niemann-Pick C1-like 1 (NPC1L1). Moreover, in order to establish a persistent infection, HCV entry is dependent on the presence of tight junction (TJ) proteins Claudin-1 (CLDN1) and Occludin (OCLN). In the liver, tight junction proteins play a role in architecture and homeostasis including sealing the apical pole of adjacent cells to form bile canaliculi and separating the basolateral domain drained by sinusoidal blood flow. In this review, we will highlight the role of liver tight junction proteins in HCV infection, and we will discuss the potential targeted therapeutic approaches to improve virus eradication.
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Affiliation(s)
- Laurent Mailly
- Université de Strasbourg, INSERM, UMR-S1110, Institut de Recherche sur les Maladies Virales et Hépatiques, F-67000 Strasbourg, France.
| | - Thomas F Baumert
- Université de Strasbourg, INSERM, UMR-S1110, Institut de Recherche sur les Maladies Virales et Hépatiques, F-67000 Strasbourg, France; Pôle Hépato-digestif, Hôpitaux Universitaires de Strasbourg, F-67000 Strasbourg, France; Institut Universitaire de France, F-75231 Paris, France.
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16
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Díaz-Coránguez M, Liu X, Antonetti DA. Tight Junctions in Cell Proliferation. Int J Mol Sci 2019; 20:E5972. [PMID: 31783547 PMCID: PMC6928848 DOI: 10.3390/ijms20235972] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 11/22/2019] [Accepted: 11/22/2019] [Indexed: 12/23/2022] Open
Abstract
Tight junction (TJ) proteins form a continuous intercellular network creating a barrier with selective regulation of water, ion, and solutes across endothelial, epithelial, and glial tissues. TJ proteins include the claudin family that confers barrier properties, members of the MARVEL family that contribute to barrier regulation, and JAM molecules, which regulate junction organization and diapedesis. In addition, the membrane-associated proteins such as MAGUK family members, i.e., zonula occludens, form the scaffold linking the transmembrane proteins to both cell signaling molecules and the cytoskeleton. Most studies of TJ have focused on the contribution to cell-cell adhesion and tissue barrier properties. However, recent studies reveal that, similar to adherens junction proteins, TJ proteins contribute to the control of cell proliferation. In this review, we will summarize and discuss the specific role of TJ proteins in the control of epithelial and endothelial cell proliferation. In some cases, the TJ proteins act as a reservoir of critical cell cycle modulators, by binding and regulating their nuclear access, while in other cases, junctional proteins are located at cellular organelles, regulating transcription and proliferation. Collectively, these studies reveal that TJ proteins contribute to the control of cell proliferation and differentiation required for forming and maintaining a tissue barrier.
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Affiliation(s)
| | | | - David A. Antonetti
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, MI 48105, USA; (M.D.-C.); (X.L.)
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17
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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: 35] [Impact Index Per Article: 5.8] [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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18
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Allam AH, Charnley M, Russell SM. Context-Specific Mechanisms of Cell Polarity Regulation. J Mol Biol 2018; 430:3457-3471. [PMID: 29886017 DOI: 10.1016/j.jmb.2018.06.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/04/2018] [Accepted: 06/04/2018] [Indexed: 12/31/2022]
Abstract
Cell polarity is an essential process shared by almost all animal tissues. Moreover, cell polarity enables cells to sense and respond to the cues provided by the neighboring cells and the surrounding microenvironment. These responses play a critical role in regulating key physiological processes, including cell migration, proliferation, differentiation, vesicle trafficking and immune responses. The polarity protein complexes regulating these interactions are highly evolutionarily conserved between vertebrates and invertebrates. Interestingly, these polarity complexes interact with each other and key signaling pathways in a cell-polarity context-dependent manner. However, the exact mechanisms by which these interactions take place are poorly understood. In this review, we will focus on the roles of the key polarity complexes SCRIB, PAR and Crumbs in regulating different forms of cell polarity, including epithelial cell polarity, cell migration, asymmetric cell division and the T-cell immunological synapse assembly and signaling.
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Affiliation(s)
- Amr H Allam
- Centre for Micro-Photonics, Faculty of Science, Engineering & Technology, Swinburne University of Technology, Hawthorn, Australia; Immune Signalling Laboratory, Peter MacCallum Cancer Centre, Parkville, Australia.
| | - Mirren Charnley
- Centre for Micro-Photonics, Faculty of Science, Engineering & Technology, Swinburne University of Technology, Hawthorn, Australia; Immune Signalling Laboratory, Peter MacCallum Cancer Centre, Parkville, Australia; Biointerface Engineering Group, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC, Australia.
| | - Sarah M Russell
- Centre for Micro-Photonics, Faculty of Science, Engineering & Technology, Swinburne University of Technology, Hawthorn, Australia; Immune Signalling Laboratory, Peter MacCallum Cancer Centre, Parkville, Australia; Department of Pathology, The University of Melbourne, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Australia.
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19
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Morgan SV, Garwood CJ, Jennings L, Simpson JE, Castelli LM, Heath PR, Mihaylov SR, Vaquéz-Villaseñor I, Minshull TC, Ince PG, Dickman MJ, Hautbergue GM, Wharton SB. Proteomic and cellular localisation studies suggest non-tight junction cytoplasmic and nuclear roles for occludin in astrocytes. Eur J Neurosci 2018; 47:1444-1456. [PMID: 29738614 PMCID: PMC6079634 DOI: 10.1111/ejn.13933] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 04/16/2018] [Indexed: 12/16/2022]
Abstract
Occludin is a component of tight junctions, which are essential structural components of the blood–brain barrier. However, occludin is expressed in cells without tight junctions, implying additional functions. We determined the expression and localisation of occludin in astrocytes in cell culture and in human brain tissue, and sought novel binding partners using a proteomic approach. Expression was investigated by immunocytochemistry and immunoblotting in the 1321N1 astrocytoma cell line and ScienCell human primary astrocytes, and by immunohistochemistry in human autopsy brain tissue. Recombinant N‐ and C‐terminal occludin was used to pull‐down proteins from 1321N1 cell lysates and protein‐binding partners identified by mass spectrometry analysis. Occludin was expressed in both the cytoplasm and nucleus of astrocytes in vitro and in vivo. Mass spectrometry identified binding to nuclear and cytoplasmic proteins, particularly those related to RNA metabolism and nuclear function. Occludin is expressed in several subcellular compartments of brain cell‐types that do not form tight junctions and the expression patterns in cell culture reflect those in human brain tissue, indicating they are suitable model systems. Proteomic analysis suggests that occludin has novel functions in neuroepithelial cells that are unrelated to tight junction formation. Further research will establish the roles of these functions in both cellular physiology and in disease states.
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Affiliation(s)
- Sarah V Morgan
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Claire J Garwood
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Luke Jennings
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Julie E Simpson
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Lydia M Castelli
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Paul R Heath
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Simeon R Mihaylov
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | | | - Thomas C Minshull
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - Paul G Ince
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Mark J Dickman
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - Guillaume M Hautbergue
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Stephen B Wharton
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
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20
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Schejter ED. Myoblast fusion: Experimental systems and cellular mechanisms. Semin Cell Dev Biol 2016; 60:112-120. [DOI: 10.1016/j.semcdb.2016.07.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 07/11/2016] [Accepted: 07/12/2016] [Indexed: 12/18/2022]
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21
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Cording J, Günther R, Vigolo E, Tscheik C, Winkler L, Schlattner I, Lorenz D, Haseloff RF, Schmidt-Ott KM, Wolburg H, Blasig IE. Redox Regulation of Cell Contacts by Tricellulin and Occludin: Redox-Sensitive Cysteine Sites in Tricellulin Regulate Both Tri- and Bicellular Junctions in Tissue Barriers as Shown in Hypoxia and Ischemia. Antioxid Redox Signal 2015; 23:1035-49. [PMID: 25919114 DOI: 10.1089/ars.2014.6162] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
UNLABELLED Tight junctions (TJs) seal paracellular clefts in epithelia/endothelia and form tissue barriers for proper organ function. TJ-associated marvel proteins (TAMPs; tricellulin, occludin, marvelD3) are thought to be relevant to regulation. Under normal conditions, tricellulin tightens tricellular junctions against macromolecules. Traces of tricellulin occur in bicellular junctions. AIMS As pathological disturbances have not been analyzed, the structure and function of human tricellulin, including potentially redox-sensitive Cys sites, were investigated under reducing/oxidizing conditions at 3- and 2-cell contacts. RESULTS Ischemia, hypoxia, and reductants redistributed tricellulin from 3- to 2-cell contacts. The extracellular loop 2 (ECL2; conserved Cys321, Cys335) trans-oligomerized between three opposing cells. Substitutions of these residues caused bicellular localization. Cys362 in transmembrane domain 4 contributed to bicellular heterophilic cis-interactions along the cell membrane with claudin-1 and marvelD3, while Cys395 in the cytosolic C-terminal tail promoted homophilic tricellullar cis-interactions. The Cys sites included in homo-/heterophilic bi-/tricellular cis-/trans-interactions contributed to cell barrier tightness for small/large molecules. INNOVATION Tricellulin forms TJs via trans- and cis-association in 3-cell contacts, as demonstrated electron and quantified fluorescence microscopically; it tightens 3- and 2-cell contacts. Tricellulin's ECL2 specifically seals 3-cell contacts redox dependently; a structural model is proposed. CONCLUSIONS TAMP ECL2 and claudins' ECL1 share functionally and structurally similar features involved in homo-/heterophilic tightening of cell-cell contacts. Tricellulin is a specific redox sensor and sealing element at 3-cell contacts and may compensate as a redox mediator for occludin loss at 2-cell contacts in vivo and in vitro. Molecular interaction mechanisms were proposed that contribute to tricellulin's function. In conclusion, tricellulin is a junctional redox regulator for ischemia-related alterations.
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Affiliation(s)
- Jimmi Cording
- 1 Leibniz-Institut für Molekulare Pharmakologie , Berlin, Germany
| | - Ramona Günther
- 1 Leibniz-Institut für Molekulare Pharmakologie , Berlin, Germany
| | - Emilia Vigolo
- 2 Department of Nephrology, Max Delbrueck Center for Molecular Medicine , Charite Berlin, Berlin, Germany
| | | | - Lars Winkler
- 1 Leibniz-Institut für Molekulare Pharmakologie , Berlin, Germany
| | | | - Dorothea Lorenz
- 1 Leibniz-Institut für Molekulare Pharmakologie , Berlin, Germany
| | | | - Kai M Schmidt-Ott
- 2 Department of Nephrology, Max Delbrueck Center for Molecular Medicine , Charite Berlin, Berlin, Germany
| | - Hartwig Wolburg
- 3 Department of General Pathology, Institute of Pathology and Neuropathology, Medical School, University of Tübingen , Tübingen, Germany
| | - Ingolf E Blasig
- 1 Leibniz-Institut für Molekulare Pharmakologie , Berlin, Germany
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22
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Affiliation(s)
- Sophia Häfner
- University of Copenhagen, BRIC Biotech Research & Innovation Centre, Lund Group, 2200 Copenhagen, Denmark.
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23
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Zhao YZ, Zhang M, Liu HF, Wang JP. Progesterone is neuroprotective by inhibiting cerebral edema after ischemia. Neural Regen Res 2015; 10:1076-81. [PMID: 26330829 PMCID: PMC4541237 DOI: 10.4103/1673-5374.160097] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2015] [Indexed: 01/08/2023] Open
Abstract
Ischemic edema can alter the structure and permeability of the blood-brain barrier. Recent studies have reported that progesterone reduces cerebral edema after cerebral ischemia. However, the underlying mechanism of this effect has not yet been elucidated. In the present study, progesterone effectively reduced Evans blue extravasation in the ischemic penumbra, but not in the ischemic core, 48 hours after cerebral ischemia in rats. Progesterone also inhibited the down-regulation of gene and protein levels of occludin and zonula occludens-1 in the penumbra. These results indicate that progesterone may effectively inhibit the down-regulation of tight junctions, thereby maintaining the integrity of the blood-brain barrier and reducing cerebral edema.
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Affiliation(s)
- Yuan-Zheng Zhao
- Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Min Zhang
- Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Heng-Fang Liu
- Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Jian-Ping Wang
- Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
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Yaffe Y, Hugger I, Yassaf IN, Shepshelovitch J, Sklan EH, Elkabetz Y, Yeheskel A, Pasmanik-Chor M, Benzing C, Macmillan A, Gaus K, Eshed-Eisenbach Y, Peles E, Hirschberg K. The myelin proteolipid plasmolipin forms oligomers and induces liquid-ordered membranes in the Golgi complex. J Cell Sci 2015; 128:2293-302. [DOI: 10.1242/jcs.166249] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 05/18/2015] [Indexed: 01/27/2023] Open
Abstract
ABSTRACT
Myelin comprises a compactly stacked massive surface area of protein-poor thick membrane that insulates axons to allow fast signal propagation. Increasing levels of the myelin protein plasmolipin (PLLP) were correlated with post-natal myelination; however, its function is unknown. Here, the intracellular localization and dynamics of PLLP were characterized in primary glial and cultured cells using fluorescently labeled PLLP and antibodies against PLLP. PLLP localized to and recycled between the plasma membrane and the Golgi complex. In the Golgi complex, PLLP forms oligomers based on fluorescence resonance energy transfer (FRET) analyses. PLLP oligomers blocked Golgi to plasma membrane transport of the secretory protein vesicular stomatitis virus G protein (VSVG), but not of a VSVG mutant with an elongated transmembrane domain. Laurdan staining analysis showed that this block is associated with PLLP-induced proliferation of liquid-ordered membranes. These findings show the capacity of PLLP to assemble potential myelin membrane precursor domains at the Golgi complex through its oligomerization and ability to attract liquid-ordered lipids. These data support a model in which PLLP functions in myelin biogenesis through organization of myelin liquid-ordered membranes in the Golgi complex.
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Affiliation(s)
- Yakey Yaffe
- Department of Pathology, Sackler School of Medicine, Tel-Aviv 69978, Israel
| | - Ilan Hugger
- Department of Pathology, Sackler School of Medicine, Tel-Aviv 69978, Israel
| | - Inbar Nevo Yassaf
- Department of Pathology, Sackler School of Medicine, Tel-Aviv 69978, Israel
| | | | - Ella H. Sklan
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv 69978, Israel
| | - Yechiel Elkabetz
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel-Aviv 69978, Israel
| | - Adva Yeheskel
- Bioinformatics Unit, G.S.W. Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Metsada Pasmanik-Chor
- Bioinformatics Unit, G.S.W. Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Carola Benzing
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and ARC Centre of Excellence in Advanced Molecular Imaging, Centre for Vascular Research University of New South Wales, Sydney, Australia 2033
| | - Alexander Macmillan
- Biomedical Imaging Facility, University of New South Wales, Sydney, Australia 2033
| | - Katharina Gaus
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and ARC Centre of Excellence in Advanced Molecular Imaging, Centre for Vascular Research University of New South Wales, Sydney, Australia 2033
| | - Yael Eshed-Eisenbach
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel 76100
| | - Elior Peles
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel 76100
| | - Koret Hirschberg
- Department of Pathology, Sackler School of Medicine, Tel-Aviv 69978, Israel
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Bauer HC, Krizbai IA, Bauer H, Traweger A. "You Shall Not Pass"-tight junctions of the blood brain barrier. Front Neurosci 2014; 8:392. [PMID: 25520612 PMCID: PMC4253952 DOI: 10.3389/fnins.2014.00392] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 11/14/2014] [Indexed: 12/31/2022] Open
Abstract
The structure and function of the barrier layers restricting the free diffusion of substances between the central nervous system (brain and spinal cord) and the systemic circulation is of great medical interest as various pathological conditions often lead to their impairment. Excessive leakage of blood-borne molecules into the parenchyma and the concomitant fluctuations in the microenvironment following a transient breakdown of the blood-brain barrier (BBB) during ischemic/hypoxic conditions or because of an autoimmune disease are detrimental to the physiological functioning of nervous tissue. On the other hand, the treatment of neurological disorders is often hampered as only minimal amounts of therapeutic agents are able to penetrate a fully functional BBB or blood cerebrospinal fluid barrier. An in-depth understanding of the molecular machinery governing the establishment and maintenance of these barriers is necessary to develop rational strategies allowing a controlled delivery of appropriate drugs to the CNS. At the basis of such tissue barriers are intimate cell-cell contacts (zonulae occludentes, tight junctions) which are present in all polarized epithelia and endothelia. By creating a paracellular diffusion constraint TJs enable the vectorial transport across cell monolayers. More recent findings indicate that functional barriers are already established during development, protecting the fetal brain. As an understanding of the biogenesis of TJs might reveal the underlying mechanisms of barrier formation during ontogenic development numerous in vitro systems have been developed to study the assembly and disassembly of TJs. In addition, monitoring the stage-specific expression of TJ-associated proteins during development has brought much insight into the “developmental tightening” of tissue barriers. Over the last two decades a detailed molecular map of transmembrane and cytoplasmic TJ-proteins has been identified. These proteins not only form a cell-cell adhesion structure, but integrate various signaling pathways, thereby directly or indirectly impacting upon processes such as cell-cell adhesion, cytoskeletal rearrangement, and transcriptional control. This review will provide a brief overview on the establishment of the BBB during embryonic development in mammals and a detailed description of the ultrastructure, biogenesis, and molecular composition of epithelial and endothelial TJs will be given.
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Affiliation(s)
- Hans-Christian Bauer
- Institute of Tendon and Bone Regeneration, Paracelsus Medical University - Spinal Cord Injury and Tissue Regeneration Center Salzburg Salzburg, Austria ; Department of Traumatology and Sports Injuries, Paracelsus Medical University Salzburg, Austria ; Austrian Cluster for Tissue Regeneration Vienna, Austria
| | - István A Krizbai
- Biological Research Centre, Institute of Biophysics, Hungarian Academy of Sciences Szeged, Hungary ; Institute of Life Sciences, Vasile Goldis Western University of Arad Arad, Romania
| | - Hannelore Bauer
- Department of Organismic Biology, University of Salzburg Salzburg, Austria
| | - Andreas Traweger
- Institute of Tendon and Bone Regeneration, Paracelsus Medical University - Spinal Cord Injury and Tissue Regeneration Center Salzburg Salzburg, Austria ; Austrian Cluster for Tissue Regeneration Vienna, Austria
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David N, Yaffe Y, Hagoel L, Elazar M, Glenn JS, Hirschberg K, Sklan EH. The interaction between the hepatitis C proteins NS4B and NS5A is involved in viral replication. Virology 2014; 475:139-49. [PMID: 25462354 DOI: 10.1016/j.virol.2014.10.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 08/07/2014] [Accepted: 10/22/2014] [Indexed: 02/07/2023]
Abstract
Hepatitis C virus (HCV) replicates in membrane associated, highly ordered replication complexes (RCs). These complexes include viral and host proteins necessary for viral RNA genome replication. The interaction network among viral and host proteins underlying the formation of these RCs is yet to be thoroughly characterized. Here, we investigated the association between NS4B and NS5A, two critical RC components. We characterized the interaction between these proteins using fluorescence resonance energy transfer and a mammalian two-hybrid system. Specific tryptophan residues within the C-terminal domain (CTD) of NS4B were shown to mediate this interaction. Domain I of NS5A, was sufficient to mediate its interaction with NS4B. Mutations in the NS4B CTD tryptophan residues abolished viral replication. Moreover, one of these mutations also affected NS5A hyperphosphorylation. These findings provide new insights into the importance of the NS4B-NS5A interaction and serve as a starting point for studying the complex interactions between the replicase subunits.
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Affiliation(s)
- Naama David
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yakey Yaffe
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Lior Hagoel
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Menashe Elazar
- Department of Medicine, Division of Gastroenterology and Hepatology, Stanford University School of Medicine, United States
| | - Jeffrey S Glenn
- Department of Medicine, Division of Gastroenterology and Hepatology, Stanford University School of Medicine, United States; Veterans Administration Medical Center, Palo Alto, CA, United States
| | - Koret Hirschberg
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ella H Sklan
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
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Haseloff RF, Dithmer S, Winkler L, Wolburg H, Blasig IE. Transmembrane proteins of the tight junctions at the blood-brain barrier: structural and functional aspects. Semin Cell Dev Biol 2014; 38:16-25. [PMID: 25433243 DOI: 10.1016/j.semcdb.2014.11.004] [Citation(s) in RCA: 249] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 11/14/2014] [Indexed: 01/27/2023]
Abstract
The blood-brain barrier (BBB) is formed by microvascular endothelial cells sealed by tetraspanning tight junction (TJ) proteins, such as claudins and TAMPs (TJ-associated marvel proteins, occludin and tricellulin). Claudins are the major components of the TJs. At the BBB, claudin-5 dominates the TJs by preventing the paracellular permeation of small molecules. On the other hand, TAMPs regulate the structure and function of the TJs; tricellulin may tighten the barrier for large molecules. This review aims at integrating and summarizing the most relevant and recent work on how the BBB is influenced by claudin-1, -3, -5, -12 and the TAMPs occludin and tricellulin, all of which are four-transmembrane TJ proteins. The exact functions of claudin-1, -3, -12 and TAMPs at this barrier still need to be elucidated.
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Affiliation(s)
- Reiner F Haseloff
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Sophie Dithmer
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Lars Winkler
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Hartwig Wolburg
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Ingolf E Blasig
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany.
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Van Itallie CM, Anderson JM. Architecture of tight junctions and principles of molecular composition. Semin Cell Dev Biol 2014; 36:157-65. [PMID: 25171873 DOI: 10.1016/j.semcdb.2014.08.011] [Citation(s) in RCA: 380] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 08/15/2014] [Accepted: 08/19/2014] [Indexed: 12/11/2022]
Abstract
The tight junction creates an intercellular barrier limiting paracellular movement of solutes and material across epithelia. Currently many proteins have been identified as components of the tight junction and understanding their architectural organization and interactions is critical to understanding the biology of the barrier. In general the architecture can be conceptualized into compartments with the transmembrane barrier proteins (claudins, occludin, JAM-A, etc.), linked to peripheral scaffolding proteins (such as ZO-1, afadin, MAGI1, etc.) which are in turned linked to actin and microtubules through numerous linkers (cingulin, myosins, protein 4.1, etc.). Within this complex network are associated many signaling proteins that affect the barrier and broader cell functions. The PDZ domain is a commonly used motif to specifically link individual junction protein pairs. Here we review some of the key proteins defining the tight junction and general themes of their organization with the perspective that much will be learned about function by characterizing the detailed architecture and subcompartments within the junction.
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Affiliation(s)
- Christina M Van Itallie
- The Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Building 50, Room 4525, 50 South Drive, Bethesda, MD 20892, USA.
| | - James M Anderson
- The Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Building 50, Room 4525, 50 South Drive, Bethesda, MD 20892, USA.
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29
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Roppolo D, Boeckmann B, Pfister A, Boutet E, Rubio MC, Dénervaud-Tendon V, Vermeer JEM, Gheyselinck J, Xenarios I, Geldner N. Functional and Evolutionary Analysis of the CASPARIAN STRIP MEMBRANE DOMAIN PROTEIN Family. PLANT PHYSIOLOGY 2014; 165:1709-1722. [PMID: 24920445 PMCID: PMC4119050 DOI: 10.1104/pp.114.239137] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/08/2014] [Indexed: 05/20/2023]
Abstract
CASPARIAN STRIP MEMBRANE DOMAIN PROTEINS (CASPs) are four-membrane-span proteins that mediate the deposition of Casparian strips in the endodermis by recruiting the lignin polymerization machinery. CASPs show high stability in their membrane domain, which presents all the hallmarks of a membrane scaffold. Here, we characterized the large family of CASP-like (CASPL) proteins. CASPLs were found in all major divisions of land plants as well as in green algae; homologs outside of the plant kingdom were identified as members of the MARVEL protein family. When ectopically expressed in the endodermis, most CASPLs were able to integrate the CASP membrane domain, which suggests that CASPLs share with CASPs the propensity to form transmembrane scaffolds. Extracellular loops are not necessary for generating the scaffold, since CASP1 was still able to localize correctly when either one of the extracellular loops was deleted. The CASP first extracellular loop was found conserved in euphyllophytes but absent in plants lacking Casparian strips, an observation that may contribute to the study of Casparian strip and root evolution. In Arabidopsis (Arabidopsis thaliana), CASPL showed specific expression in a variety of cell types, such as trichomes, abscission zone cells, peripheral root cap cells, and xylem pole pericycle cells.
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Affiliation(s)
- Daniele Roppolo
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Brigitte Boeckmann
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Alexandre Pfister
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Emmanuel Boutet
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Maria C Rubio
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Valérie Dénervaud-Tendon
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Joop E M Vermeer
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Jacqueline Gheyselinck
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Ioannis Xenarios
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
| | - Niko Geldner
- Department of Plant Molecular Biology, University of Lausanne, Quartier Sorge, Lausanne 1015, Switzerland (D.R., A.P., M.C.R., V.D.-T., J.E.M.V., N.G.);Swiss Institute of Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland (B.B., E.B., I.X.);Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, 50080 Zaragoza, Spain (M.C.R.);Vital-IT Group and University of Lausanne, Quartier Sorge, Bâtiment Génopode, Lausanne 1015, Switzerland (I.X.); andInstitute of Plant Sciences, University of Bern, 3013 Bern, Switzerland (D.R., J.G.)
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Bewley MC, Tash BR, Tian F, Flanagan JM. A complex affair: Attraction and repulsion make occludin and ZO-1 function! Tissue Barriers 2014; 1:e23496. [PMID: 24665376 PMCID: PMC3879131 DOI: 10.4161/tisb.23496] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 12/22/2012] [Accepted: 01/04/2013] [Indexed: 01/02/2023] Open
Abstract
Tight junctions (TJs) are protein complexes comprised of claudins, which anchor them in the membrane and numerous cytosolic scaffolding proteins including MAGI, MUPP1, cingulin and members of the Zonula Occludens (ZO) family. Originally, their main function was thought to be as a paracellular barrier. More recently, however, additional roles in signal transduction, differentiation and proliferation have been reported. Dysregulation is associated with a wide range of disease states, including diabetic retinopathy, irritable bowel disease and some cancers. ZO proteins and occludin form a protein complex that appears to act as a master regulator of TJ assembly/disassembly. Recent studies have highlighted the structural character of the primary ZO-1:occludin interaction and identified regions on occludin that control association and disassociation of TJ in a phosphorylation-dependent manner. We hypothesize that regions within ZO-1 in the so-called U5 and U6 regions behave in a similar manner.
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Affiliation(s)
- Maria C Bewley
- Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey, PA USA
| | - Brian R Tash
- Renal Electrolyte and Hypertension Division; University of Pennsylvania; Philadelphia, PA USA
| | - Fang Tian
- Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey, PA USA
| | - John M Flanagan
- Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey, PA USA
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Shahheydari H, Frost S, Smith BJ, Groblewski GE, Chen Y, Byrne JA. Identification of PLP2 and RAB5C as novel TPD52 binding partners through yeast two-hybrid screening. Mol Biol Rep 2014; 41:4565-72. [PMID: 24604726 DOI: 10.1007/s11033-014-3327-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 02/26/2014] [Indexed: 01/01/2023]
Abstract
Tumor protein D52 (TPD52) is overexpressed in different cancers, but its molecular functions are poorly defined. A large, low-stringency yeast two-hybrid screen using full-length TPD52 bait identified known partners (TPD52, TPD52L1, TPD52L2, MAL2) and four other preys that reproducibly bound TPD52 and TPD52L1 baits (PLP2, RAB5C, GOLGA5, YIF1A). PLP2 and RAB5 interactions with TPD52 were confirmed in pull down assays, with interaction domain mapping experiments indicating that both proteins interact with a novel binding region of TPD52. This study provides insights into TPD52 functions, and ways to maximise the efficiency of low-stringency yeast two-hybrid screens.
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Affiliation(s)
- Hamideh Shahheydari
- Children's Cancer Research Unit, Kids Research Institute, The Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW, 2145, Australia
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Bellmann C, Schreivogel S, Günther R, Dabrowski S, Schümann M, Wolburg H, Blasig IE. Highly conserved cysteines are involved in the oligomerization of occludin-redox dependency of the second extracellular loop. Antioxid Redox Signal 2014; 20:855-67. [PMID: 23923978 PMCID: PMC3924802 DOI: 10.1089/ars.2013.5288] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
UNLABELLED The tight junction (TJ) marker occludin is a 4-transmembrane domain (TMD) protein with unclear physiological and pathological functions, interacting with other TJ proteins. It oligomerizes and is redox sensitive. However, oligomerization sites and mechanisms are unknown. AIMS To identify hypoxia-sensitive binding sites, we investigated the consequences of amino-acid substitutions of highly conserved cysteines in human occludin, under normal and hypoxic incubations. RESULTS (i) The extracellular loop 2 (ECL2) showed homophilic trans- and cis-association between opposing cells and along the cell membrane, respectively, caused by a loop properly folded via an intraloop disulfide bridge between the shielded C216 and C237. Hypoxia and reductants prevented the associations. (ii) C82 in TMD1 directly cis-associated without disulfide formation. (iii) C76 in TMD1 and C148 in TMD2 limited the trans-interaction; C76 also limited occludin-related paracellular tightness and changed the strand morphology of claudin-1. (iv) The diminished binding strength found after substituting C82, C216, or C237 was accompanied by increased occludin mobility in the cell membrane. INNOVATION The data enable the first experimentally proven structural model of occludin and its homophilic interaction sites, in which the ECL2, via intraloop disulfide formation, has a central role in occludin's hypoxia-sensitive oligomerization and to regulate the structure of TJs. CONCLUSION Our findings support the new concept that occludin acts as a hypoxiasensor and contributes toward regulating the TJ assembly redox dependently. This is of pathogenic relevance for tissue barrier injury with reducing conditions. The ECL2 disulfide might be a model for four TMD proteins in TJs with two conserved cysteines in an ECL.
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Tight junction regulation through vesicle trafficking: bringing cells together. Biochem Soc Trans 2014; 42:195-200. [DOI: 10.1042/bst20130162] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Epithelial layers are integral for many physiological processes and are maintained by intercellular adhesive structures. During disease, these structures can disassemble, leading to breakdown of epithelia. TJs (tight junctions) are one type of intercellular adhesion. Loss of TJs has been linked to the pathogenesis of many diseases. The present review focuses on the role of vesicle trafficking in regulation of TJs, in particular trafficking of the TJ protein occludin. We examine how endocytosis and endosomal recycling modulate occludin localization under steady-state conditions and during stimulated TJ disassembly.
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Dörfel MJ, Westphal JK, Bellmann C, Krug SM, Cording J, Mittag S, Tauber R, Fromm M, Blasig IE, Huber O. CK2-dependent phosphorylation of occludin regulates the interaction with ZO-proteins and tight junction integrity. Cell Commun Signal 2013; 11:40. [PMID: 23758859 PMCID: PMC3695765 DOI: 10.1186/1478-811x-11-40] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 06/04/2013] [Indexed: 01/28/2023] Open
Abstract
Background Casein kinase 2 (CK2) is a ubiquitously expressed Ser/Thr kinase with multiple functions in the regulation of cell proliferation and transformation. In targeting adherens and tight junctions (TJs), CK2 modulates the strength and dynamics of epithelial cell-cell contacts. Occludin previously was identified as a substrate of CK2, however the functional consequences of CK2-dependent occludin phosphorylation on TJ function were unknown. Results Here, we present evidence that phosphorylation of a Thr400-XXX-Thr404-XXX-Ser408 motif in the C-terminal cytoplasmic tail of human occludin regulates assembly/disassembly and barrier properties of TJs. In contrast to wildtype and T400A/T404A/S408A-mutated occludin, a phospho-mimetic Occ-T400E/T404E/S408E construct was impaired in binding to ZO-2. Interestingly, pre-phosphorylation of a GST-Occ C-terminal domain fusion protein attenuated binding to ZO-2, whereas, binding to ZO-1 was not affected. Moreover, Occ-T400E/T404E/S408E showed delayed reassembly into TJs in Ca2+-switch experiments. Stable expression of Occ-T400E/T404E/S408E in MDCK C11 cells augments barrier properties in enhancing paracellular resistance in two-path impedance spectroscopy, whereas expression of wildtype and Occ-T400A/T404A/S408A did not affect transepithelial resistance. Conclusions These results suggest an important role of CK2 in epithelial tight junction regulation. The occludin sequence motif at amino acids 400–408 apparently represents a hotspot for Ser/Thr-kinase phosphorylation and depending on the residue(s) which are phosphorylated it differentially modulates the functional properties of the TJ.
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Affiliation(s)
- Max J Dörfel
- Institute of Biochemistry II, Jena University Hospital, Friedrich-Schiller-University Jena, Nonnenplan 2, 07743 Jena, Germany.
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An N-terminal amphipathic helix in dengue virus nonstructural protein 4A mediates oligomerization and is essential for replication. J Virol 2013; 87:4080-5. [PMID: 23325687 DOI: 10.1128/jvi.01900-12] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Dengue virus (DENV) causes dengue fever, a major health concern worldwide. We identified an amphipathic helix (AH) in the N-terminal region of the viral nonstructural protein 4A (NS4A). Disruption of its amphipathic nature using mutagenesis reduced homo-oligomerization and abolished viral replication. These data emphasize the significance of NS4A in the life cycle of the dengue virus and demarcate it as a target for the design of novel antiviral therapy.
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McCaffrey G, Davis TP. Physiology and pathophysiology of the blood-brain barrier: P-glycoprotein and occludin trafficking as therapeutic targets to optimize central nervous system drug delivery. J Investig Med 2012; 60:1131-40. [PMID: 23138008 PMCID: PMC3851303 DOI: 10.2310/jim.0b013e318276de79] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The blood-brain barrier (BBB) is a physical and metabolic barrier that separates the central nervous system from the peripheral circulation. Central nervous system drug delivery across the BBB is challenging, primarily because of the physical restriction of paracellular diffusion between the endothelial cells that comprise the microvessels of the BBB and the activity of efflux transporters that quickly expel back into the capillary lumen a wide variety of xenobiotics. Therapeutic manipulation of protein trafficking is emerging as a novel means of modulating protein function, and in this minireview, the targeting of the trafficking of 2 key BBB proteins, P-glycoprotein and occludin, is presented as a novel, reversible means of optimizing central nervous system drug delivery.
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Affiliation(s)
- Gwen McCaffrey
- Department of Medical Pharmacology, University of Arizona College of Medicine, Tucson, AZ 85745, USA.
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Luissint AC, Artus C, Glacial F, Ganeshamoorthy K, Couraud PO. Tight junctions at the blood brain barrier: physiological architecture and disease-associated dysregulation. Fluids Barriers CNS 2012; 9:23. [PMID: 23140302 PMCID: PMC3542074 DOI: 10.1186/2045-8118-9-23] [Citation(s) in RCA: 441] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 10/21/2012] [Indexed: 01/01/2023] Open
Abstract
The Blood–brain barrier (BBB), present at the level of the endothelium of cerebral blood vessels, selectively restricts the blood-to-brain paracellular diffusion of compounds; it is mandatory for cerebral homeostasis and proper neuronal function. The barrier properties of these specialized endothelial cells notably depend on tight junctions (TJs) between adjacent cells: TJs are dynamic structures consisting of a number of transmembrane and membrane-associated cytoplasmic proteins, which are assembled in a multimolecular complex and acting as a platform for intracellular signaling. Although the structural composition of these complexes has been well described in the recent years, our knowledge about their functional regulation still remains fragmentary. Importantly, pericytes, embedded in the vascular basement membrane, and perivascular microglial cells, astrocytes and neurons contribute to the regulation of endothelial TJs and BBB function, altogether constituting the so-called neurovascular unit. The present review summarizes our current understanding of the structure and functional regulation of endothelial TJs at the BBB. Accumulating evidence points to a correlation between BBB dysfunction, alteration of TJ complexes and progression of a variety of CNS diseases, such as stroke, multiple sclerosis and brain tumors, as well as neurodegenerative diseases like Parkinson’s and Alzheimer’s diseases. Understanding how TJ integrity is controlled may thus help improve drug delivery across the BBB and the design of therapeutic strategies for neurological disorders.
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