1
|
Ciavolella G, Ferrand N, Sabbah M, Perthame B, Natalini R. A Model for Membrane Degradation Using a Gelatin Invadopodia Assay. Bull Math Biol 2024; 86:30. [PMID: 38347328 DOI: 10.1007/s11538-024-01260-w] [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: 07/11/2023] [Accepted: 01/15/2024] [Indexed: 02/15/2024]
Abstract
One of the most crucial and lethal characteristics of solid tumors is represented by the increased ability of cancer cells to migrate and invade other organs during the so-called metastatic spread. This is allowed thanks to the production of matrix metalloproteinases (MMPs), enzymes capable of degrading a type of collagen abundant in the basal membrane separating the epithelial tissue from the connective one. In this work, we employ a synergistic experimental and mathematical modelling approach to explore the invasion process of tumor cells. A mathematical model composed of reaction-diffusion equations describing the evolution of the tumor cells density on a gelatin substrate, MMPs enzymes concentration and the degradation of the gelatin is proposed. This is completed with a calibration strategy. We perform a sensitivity analysis and explore a parameter estimation technique both on synthetic and experimental data in order to find the optimal parameters that describe the in vitro experiments. A comparison between numerical and experimental solutions ends the work.
Collapse
Affiliation(s)
- Giorgia Ciavolella
- Inria Centre de l'Université de Bordeaux, Institut de Mathématiques de Bordeaux, CNRS UMR 5251, 351 cours de la Libération, 33405, Talence Cedex, France.
| | - Nathalie Ferrand
- Sorbonne Université Cancer Biology and Therapeutics, INSERM, CNRS, Institut Universitaire de Cancérologie, Saint- Antoine Research Center (CRSA), 75012, Paris, France
| | - Michéle Sabbah
- Sorbonne Université Cancer Biology and Therapeutics, INSERM, CNRS, Institut Universitaire de Cancérologie, Saint- Antoine Research Center (CRSA), 75012, Paris, France
| | - Benoît Perthame
- Sorbonne Université, Inria, Université de Paris, Laboratoire Jacques-Louis Lions, UMR7598, 4 place Jussieu, 75005, Paris, France
| | - Roberto Natalini
- Istituto per le Applicazioni del Calcolo 'M.Picone', Rome, Italy
| |
Collapse
|
2
|
Schmiedinger T, Vogel GF, Eiter O, Pfaller K, Kaufmann WA, Flörl A, Gutleben K, Schönherr S, Witting B, Lechleitner TW, Ebner HL, Seppi T, Hess MW. Cryo-immunoelectron microscopy of adherent cells improved by the use of electrospun cell culture substrates. Traffic 2013; 14:886-94. [PMID: 23631675 DOI: 10.1111/tra.12080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 04/25/2013] [Accepted: 04/30/2013] [Indexed: 01/27/2023]
Abstract
Electrospun nanofibres are an excellent cell culture substrate, enabling the fast and non-disruptive harvest and transfer of adherent cells for microscopical and biochemical analyses. Metabolic activity and cellular structures are maintained during the only half a minute-long harvest and transfer process. We show here that such samples can be optimally processed by means of cryofixation combined either with freeze-substitution, sample rehydration and cryosection-immunolabelling or with freeze-fracture replica-immunolabelling. Moreover, electrospun fibre substrates are equally suitable for complementary approaches, such as biochemistry, fluorescence microscopy and cytochemistry.
Collapse
Affiliation(s)
- Thomas Schmiedinger
- Department of Therapeutic Radiology and Oncology, Innsbruck Medical University, Anichstrasse 35, A-6020, Innsbruck, Austria
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Martin KH, Hayes KE, Walk EL, Ammer AG, Markwell SM, Weed SA. Quantitative measurement of invadopodia-mediated extracellular matrix proteolysis in single and multicellular contexts. J Vis Exp 2012:e4119. [PMID: 22952016 DOI: 10.3791/4119] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Cellular invasion into local tissues is a process important in development and homeostasis. Malregulated invasion and subsequent cell movement is characteristic of multiple pathological processes, including inflammation, cardiovascular disease and tumor cell metastasis. Focalized proteolytic degradation of extracellular matrix (ECM) components in the epithelial or endothelial basement membrane is a critical step in initiating cellular invasion. In tumor cells, extensive in vitro analysis has determined that ECM degradation is accomplished by ventral actin-rich membrane protrusive structures termed invadopodia. Invadopodia form in close apposition to the ECM, where they moderate ECM breakdown through the action of matrix metalloproteinases (MMPs). The ability of tumor cells to form invadopodia directly correlates with the ability to invade into local stroma and associated vascular components. Visualization of invadopodia-mediated ECM degradation of cells by fluorescent microscopy using dye-labeled matrix proteins coated onto glass coverslips has emerged as the most prevalent technique for evaluating the degree of matrix proteolysis and cellular invasive potential. Here we describe a version of the standard method for generating fluorescently-labeled glass coverslips utilizing a commercially available Oregon Green-488 gelatin conjugate. This method is easily scaled to rapidly produce large numbers of coated coverslips. We show some of the common microscopic artifacts that are often encountered during this procedure and how these can be avoided. Finally, we describe standardized methods using readily available computer software to allow quantification of labeled gelatin matrix degradation mediated by individual cells and by entire cellular populations. The described procedures provide the ability to accurately and reproducibly monitor invadopodia activity, and can also serve as a platform for evaluating the efficacy of modulating protein expression or testing of anti-invasive compounds on extracellular matrix degradation in single and multicellular settings.
Collapse
Affiliation(s)
- Karen H Martin
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, USA
| | | | | | | | | | | |
Collapse
|
4
|
Heidenreich DJ, Reedy MV, Brauer PR. Homocysteine enhances cardiac neural crest cell attachment in vitro by increasing intracellular calcium levels. Dev Dyn 2008; 237:2117-28. [PMID: 18651663 DOI: 10.1002/dvdy.21644] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Elevated homocysteine (Hcys) increases the risk of neurocristopathies. Previous studies show Hcys inhibits neural crest (NC) cell migration in vivo. However, the mechanisms responsible for this effect are unknown. Here, we evaluated the effect of Hcys on NC cell attachment in vitro and determined if any of the effects were due to altered Ca2+ signaling. We found Hcys enhanced NC cell attachment in a dose and substrate-dependent manner. Ionomycin mimicked the effect of Hcys while BAPTA-AM and 2-APB blocked the effect of Hcys on NC attachment. In contrast, inhibitors of plasma membrane Ca2+ channels had no effect on NC attachment. Hcys also increased the emission of the intracellular Ca2+-sensitive probe, Fluo-4. These results show Hcys alters NC attachment by triggering an increase in intracellular Ca2+ possibly by generating inositol triphosphate. Hence, the teratogenic effect ascribed to Hcys may be due to perturbation of intracellular Ca2+ signaling.
Collapse
Affiliation(s)
- David J Heidenreich
- Department of Biomedical Sciences, Creighton University, Omaha, Nebraska 68178, USA
| | | | | |
Collapse
|
5
|
Leslie M. More than one way to attach. J Biophys Biochem Cytol 2005. [PMCID: PMC2258040 DOI: 10.1083/jcb1713fta2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
6
|
Vainionpää N, Kikkawa Y, Lounatmaa K, Miner JH, Rousselle P, Virtanen I. Laminin-10 and Lutheran blood group glycoproteins in adhesion of human endothelial cells. Am J Physiol Cell Physiol 2005; 290:C764-75. [PMID: 16236823 DOI: 10.1152/ajpcell.00285.2005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Laminin alpha5-chain, a constituent of laminins-10 and -11, is expressed in endothelial basement membranes. In this study we evaluated the roles of alpha5 laminins and Lutheran blood group glycoproteins (Lu), recently identified receptors of the laminin alpha5-chain, in the adhesion of human dermal microvascular and pulmonary artery endothelial cells. Field emission scanning electron microscopy and immunohistochemistry showed that the endothelial cells spread on laminin-10 and formed fibronectin-positive fibrillar adhesion structures. Immunoprecipitation results suggested that the cells produced fibronectin, which they could use as adhesion substratum, during the adhesion process. When the protein synthesis during the adhesion was inhibited with cycloheximide, the formation of fibrillar adhesions on laminin-10 was abolished, suggesting that laminin-10 does not stimulate the formation of any adhesion structures. Northern and Western blot analyses showed that the cells expressed M(r) 78,000 and 85,000 isoforms of Lu. Quantitative cell adhesion assays showed that in the endothelial cell adhesion to laminin-10, Lu acted in concert with integrins beta(1) and alpha(v)beta(3), whereas in the adhesion to laminin-10/11, Lu and integrin beta(1) were involved. In the cells adhering to the alpha5 laminins, Lu and the integrins showed uniform cell surface distribution. These findings indicate that alpha5 laminins stimulate endothelial cell adhesion but not the formation of fibrillar or focal adhesions. Lu mediates the adhesion of human endothelial cells to alpha5 laminins in collaboration with integrins beta(1) and alpha(v)beta(3).
Collapse
Affiliation(s)
- Noora Vainionpää
- Institute of Biomedicine/Anatomy, PO Box 63, Haartmaninkatu 8, University of Helsinki, FIN-00014 Helsinki, Finland.
| | | | | | | | | | | |
Collapse
|
7
|
Alfandari D, Cousin H, Gaultier A, Smith K, White JM, Darribère T, DeSimone DW. Xenopus ADAM 13 is a metalloprotease required for cranial neural crest-cell migration. Curr Biol 2001; 11:918-30. [PMID: 11448768 DOI: 10.1016/s0960-9822(01)00263-9] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Cranial neural-crest (CNC) cells originate from the lateral edge of the anterior neuroepithelium and migrate to form parts of the peripheral nervous system, muscles, cartilage, and bones of the face. Neural crest-cell migration involves the loss of adhesion from the surrounding neuroepithelium and a corresponding increase in cell adhesion to the extracellular matrix (ECM) present in migratory pathways. While proteolytic activity is likely to contribute to the regulation of neural crest-cell adhesion and migration, the role of a neural crest-specific protease in these processes has yet to be demonstrated. We previously showed that CNC cells express ADAM 13, a cell surface metalloprotease/disintegrin. Proteins of this family are known to act in cell-cell adhesion and as sheddases. ADAMs have also been proposed to degrade the ECM, but this has not yet been shown in a physiological context. RESULTS Using a tissue transplantation technique, we show that Xenopus CNC cells overexpressing wild-type ADAM 13 migrate along the same hyoid, branchial, and mandibular pathways used by normal CNC cells. In contrast, CNC cell grafts that express protease-defective ADAM 13 fail to migrate along the hyoid and branchial pathways. In addition, ectopic expression of wild-type ADAM 13 results in a gain-of-function phenotype in embryos, namely the abnormal positioning of trunk neural-crest cells. We further show that explanted embryonic tissues expressing wild-type, but not protease-defective, ADAM 13 display decreased cell-matrix adhesion. Purified ADAM 13 can cleave fibronectin, and tissue culture cells that express wild-type, but not protease-defective, ADAM 13 can remodel a fibronectin substrate. CONCLUSIONS Our findings support the hypothesis that the protease activity of ADAM 13 plays a critical role in neural crest-cell migration along defined pathways. We propose that the ADAM 13-dependent modification of ECM and/or other guidance molecules is a key step in the directed migration of the CNC.
Collapse
Affiliation(s)
- D Alfandari
- Laboratoire de Biologie Moléculaire et Cellulaire du Developpement, Equipe Adhesion et Migration Cellulaires, 9 quai St. Bernard Bat C, 7 degrees etage, 75005, Paris, France.
| | | | | | | | | | | | | |
Collapse
|
8
|
Katz BZ, Zamir E, Bershadsky A, Kam Z, Yamada KM, Geiger B. Physical state of the extracellular matrix regulates the structure and molecular composition of cell-matrix adhesions. Mol Biol Cell 2000; 11:1047-60. [PMID: 10712519 PMCID: PMC14830 DOI: 10.1091/mbc.11.3.1047] [Citation(s) in RCA: 326] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
This study establishes that the physical state of the extracellular matrix can regulate integrin-mediated cytoskeletal assembly and tyrosine phosphorylation to generate two distinct types of cell-matrix adhesions. In primary fibroblasts, alpha(5)beta(1) integrin associates mainly with fibronectin fibrils and forms adhesions structurally distinct from focal contacts, independent of actomyosin-mediated cell contractility. These "fibrillar adhesions" are enriched in tensin, but contain low levels of the typical focal contact components paxillin, vinculin, and tyrosine-phosphorylated proteins. However, when the fibronectin is covalently linked to the substrate, alpha(5)beta(1) integrin forms highly tyrosine-phosphorylated, "classical" focal contacts containing high levels of paxillin and vinculin. These experiments indicate that the physical state of the matrix, not just its molecular composition, is a critical factor in defining cytoskeletal organization and phosphorylation at adhesion sites. We propose that molecular organization of adhesion sites is controlled by at least two mechanisms: 1) specific integrins associate with their ligands in transmembrane complexes with appropriate cytoplasmic anchor proteins (e.g., fibronectin-alpha(5)beta(1) integrin-tensin complexes), and 2) physical properties (e.g., rigidity) of the extracellular matrix regulate local tension at adhesion sites and activate local tyrosine phosphorylation, recruiting a variety of plaque molecules to these sites. These mechanisms generate structurally and functionally distinct types of matrix adhesions in fibroblasts.
Collapse
Affiliation(s)
- B Z Katz
- Craniofacial Developmental Biology and Regeneration Branch, National Institute of Craniofacial and Dental Research, National Institutes of Health, Bethesda, MD, USA
| | | | | | | | | | | |
Collapse
|
9
|
Chen WT, Wang JY. Specialized surface protrusions of invasive cells, invadopodia and lamellipodia, have differential MT1-MMP, MMP-2, and TIMP-2 localization. Ann N Y Acad Sci 1999; 878:361-71. [PMID: 10415741 DOI: 10.1111/j.1749-6632.1999.tb07695.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Surface protrusions, invadopodia, and analogous lamellipodia at the leading edge of an invasive cell, which make contact with the underlying extracellular matrix (ECM), are the main motor for cellular locomotion and invasion. Previous studies have demonstrated that invadopodia, but not lamellipodia, are sites of ECM degradation on the cell surface. Such degradative activity is in part due to the localization of latent matrix metalloproteinase-2 (MMP-2) and membrane type-1 MMP (MT1-MMP) to invadopodia, where MMP activation occurs. Although lamellipodia exhibit similar structure and mobility to invadopodia, lamellipodia, by virtue of their location at the cellular periphery, are readily accessible to the soluble tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and blood-borne inhibitors. We show here that TIMP-2 co-localizes with MT1-MMP and MMP-2 at lamellipodia but not with that of invadopodia. Thus, the MMP-TIMP localization at lamellipodia may be a key mechanism for the regulation of MMP activation on the cell surface, which in turn governs expression of the cell-invasive phenotype.
Collapse
Affiliation(s)
- W T Chen
- Department of Medicine/Medical Oncology, State University of New York at Stony Brook, New York 11794-8160, USA.
| | | |
Collapse
|
10
|
Bourdoulous S, Orend G, MacKenna DA, Pasqualini R, Ruoslahti E. Fibronectin matrix regulates activation of RHO and CDC42 GTPases and cell cycle progression. J Cell Biol 1998; 143:267-76. [PMID: 9763437 PMCID: PMC2132814 DOI: 10.1083/jcb.143.1.267] [Citation(s) in RCA: 185] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/1998] [Revised: 08/24/1998] [Indexed: 11/22/2022] Open
Abstract
Adherent cells assemble fibronectin into a fibrillar matrix on their apical surface. The fibril formation is initiated by fibronectin binding to the integrins alpha5 beta1 and alphav beta3, and is completed by a process that includes fibronectin self-assembly. We found that a 76- amino acid fragment of fibronectin (III1-C) that forms one of the self-assembly sites caused disassembly of preformed fibronectin matrix without affecting cell adhesion. Treating attached fibroblasts or endothelial cells with III1-C inhibited cell migration and proliferation. Rho-dependent stress fiber formation and Rho-dependent focal contact protein phosphorylation were also inhibited, whereas Cdc42 was activated, leading to actin polymerization into filopodia. ACK (activated Cdc42-binding kinase) and p38 MAPK (mitogen-activated protein kinase), two downstream effectors of Cdc42, were activated, whereas PAK (p21-activated kinase) and JNK/SAPK (c-Jun NH2-terminal kinase/ stress-activated protein kinase) were inhibited. III1-C treatment also modulated activation of JNK and ERK (extracellular signal-regulated kinases) in response to growth factors, and reduced the activity of the cyclin E-cdk2 complex. These results indicate that the absence of fibronectin matrix causes activation of Cdc42, and that fibronectin matrix is required for Rho activation and cell cycle progression.
Collapse
Affiliation(s)
- S Bourdoulous
- Cancer Research Center, The Burnham Institute, La Jolla, California 92037, USA
| | | | | | | | | |
Collapse
|
11
|
Pöllänen J, Stephens RW, Vaheri A. Directed plasminogen activation at the surface of normal and malignant cells. Adv Cancer Res 1991; 57:273-328. [PMID: 1950706 DOI: 10.1016/s0065-230x(08)61002-7] [Citation(s) in RCA: 207] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- J Pöllänen
- Department of Virology, University of Helsinki, Finland
| | | | | |
Collapse
|
12
|
Lombardi L, Ballinari D, Bongarzone I, Migliari M, Mondellini P, Traversari C, Modina S. Ultrastructural cytoskeleton alterations and modification of actin expression in the NIH/3T3 cell line after transformation with Ha-ras-activated oncogene. CELL MOTILITY AND THE CYTOSKELETON 1990; 15:220-9. [PMID: 1692516 DOI: 10.1002/cm.970150405] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cytoskeleton alterations of NIH/3T3 fibroblast monolayers transfected with Ha-ras-activated oncogene were studied by immunofluorescence, immunoelectron microscopy, and immunoelectrophoretic analysis of actin isoforms. Transformation foci were found to consist of cells with a round shape and rare stress fibers that spread sparsely, forming rare focal contacts and fibronexuses. The loss of stress fibers in transformed cells was confirmed by staining with rhodamine-phalloidin and with a fluorescinated anti-non-muscle cell actin antibody. The transformed cells were anchored to the substrate prominently by filaments that contained fibronectin, as showed by immunoelectron microscopy. A down-regulation of alpha-actin isoform was observed by immunofluorescence and immunoblotting analysis using a specific monoclonal antibody. The diffuse distribution of alpha-actin, lacking a specific association with stress fibers, challenges the hypothesis of a connection between alpha-actin down-regulation and stress fiber loss.
Collapse
Affiliation(s)
- L Lombardi
- Division of Experimental Oncology A, University of Milan, Italy
| | | | | | | | | | | | | |
Collapse
|
13
|
Bart KM, Schumacher G. Use of a gelatin substrate for viewing sessile aquatic organisms by scanning electron microscopy. JOURNAL OF ELECTRON MICROSCOPY TECHNIQUE 1989; 11:170-1. [PMID: 2709136 DOI: 10.1002/jemt.1060110213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- K M Bart
- Hamilton College, Biology Department, Clinton, New York 13323
| | | |
Collapse
|
14
|
Abstract
Focal adhesions are areas of cell surfaces where specializations of cytoskeletal, membrane and extracellular components combine to produce stable cell-matrix interactions. The morphology of these adhesions and the components identified in them are discussed together with possible mechanisms of their formation.
Collapse
Affiliation(s)
- A Woods
- Department of Cell Biology, University of Alabama, Birmingham 35294
| | | |
Collapse
|
15
|
Saga S, Nagata K, Chen WT, Yamada KM. pH-dependent function, purification, and intracellular location of a major collagen-binding glycoprotein. J Cell Biol 1987; 105:517-27. [PMID: 3038929 PMCID: PMC2114926 DOI: 10.1083/jcb.105.1.517] [Citation(s) in RCA: 148] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
A major collagen-binding heat shock protein of molecular mass 47,000 D was found to bind to collagen by a pH-dependent interaction; binding was abolished at pH 6.3. Native 47-kD protein could therefore be purified from chick embryo homogenates in milligram quantities by gelatin-affinity chromatography and gentle acidic elution. Rat monoclonal and rabbit polyclonal antibodies were generated against the purified 47-kD protein. Immunofluorescence microscopy of cultured chick embryo fibroblasts with these antibodies revealed bright, granular perinuclear staining as well as a weaker reticular network structure towards the cell periphery, suggesting that this protein was located in the endoplasmic reticulum. No immunofluorescence staining was detected on the cell surface. Double-staining experiments with these antibodies and fluorescently labeled wheat-germ agglutinin suggested that the 47-kD protein was absent from the Golgi apparatus. Localization of the 47-kD protein in the endoplasmic reticulum but not in the Golgi complex was confirmed by immunoelectron microscopy. In vivo localization studies using immunohistochemistry of cryostat sections of chick liver revealed that the 47-kD protein was present in fibrocytes, Kupffer cells, and smooth muscle cells. It was absent from hepatocytes and the epithelia of bile ducts or sinusoidal endothelium. This major transformation- and heat shock-regulated glycoprotein is thus localized intracellularly, is expressed in only certain cells, and functions in a pH-regulated manner. These findings suggest that this glycoprotein is not likely to be a general cell-surface collagen receptor, but may instead play roles in intracellular protein processing or translocation.
Collapse
|
16
|
Baetscher M, Pumplin DW, Bloch RJ. Vitronectin at sites of cell-substrate contact in cultures of rat myotubes. J Biophys Biochem Cytol 1986; 103:369-78. [PMID: 2426279 PMCID: PMC2113821 DOI: 10.1083/jcb.103.2.369] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Affinity-purified antibodies to the serum glycoprotein, vitronectin, were used to study sites of cell-substrate contact in cultures of rat myotubes and fibroblasts. Cells were removed from the substrate by treatment with saponin, leaving fragments of plasma membrane attached to the glass coverslip. When stained for vitronectin by indirect immunofluorescence, large areas of the substrate were brightly labeled. The focal contacts of fibroblasts and the broad adhesion plaques of myotubes appeared black, however, indicating that the antibodies had failed to react with those areas. Contact sites within the adhesion plaque remained unlabeled after saponin-treated samples were extracted with Triton X-100, or after intact cultures were sheared with a stream of fixative. These procedures expose extracellular macromolecules at the cell-substrate interface, which can then be labeled with concanavalin A. In contrast, when samples were sheared and then sonicated to remove all the cellular material from the coverslip, the entire substrate labeled extensively and almost uniformly with anti-vitronectin. Extracellular molecules associated with substrate contacts were also studied after freeze-fracture, using a technique we term "post-release fracture labeling." Platinum replicas of the external membrane were removed from the glass with hydrofluoric acid to expose the extracellular material. Anti-vitronectin, bound to the replicas and visualized by a second antibody conjugated to colloidal gold, labeled the broad areas of close myotube-substrate attachment and the nearby glass equally well. Our results are consistent with the hypothesis that vitronectin is present at all sites of cell-substrate contact, but that its antigenic sites are obscured by material deposited by both myotube and fibroblast cells.
Collapse
|
17
|
Duband JL, Rocher S, Chen WT, Yamada KM, Thiery JP. Cell adhesion and migration in the early vertebrate embryo: location and possible role of the putative fibronectin receptor complex. J Cell Biol 1986; 102:160-78. [PMID: 2934401 PMCID: PMC2114053 DOI: 10.1083/jcb.102.1.160] [Citation(s) in RCA: 240] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Using a combined in vivo and in vitro approach, we have analyzed the immunofluorescent localization and function of a 140,000-mol-wt glycoprotein complex implicated in cell adhesion to fibronectin (FN), with particular emphasis on neural crest cell adhesion and migration. This putative fibronectin receptor complex (FN-receptor) was detectable in almost all tissues derived from each of the three primary germ layers. It was present in both mesenchymal and epithelial cells, and was particularly enriched at sites close to concentrations of FN, e.g., at the basal surfaces of epithelial cells. It was also present on neural crest cells. The distribution and function of this putative receptor was then analyzed on individual cells in vitro. It was diffusely organized on highly locomotory neural crest cells and somitic fibroblasts. Both motile cell types also displayed relatively low numbers of focal contacts and microfilament bundles and limited amounts of localized vinculin, alpha-actinin, and endogenous FN. In contrast, the FN-receptor in stationary embryonic cells, i.e., somitic cells after long-term culture or ectodermal cells, existed in characteristic linear patterns generally co-distributed with alpha-actinin and fibers of endogenous FN. Anti-FN-receptor antibodies inhibited the adhesion to FN of motile embryonic cells, but not of stationary fibroblasts. However, these same antibodies adsorbed to substrata readily mediated adhesion and spreading of cells, but were much less effective for cell migration. Our results demonstrate a widespread occurrence in vivo of the putative FN-receptor, with high concentrations near FN. Embryonic cell migration was associated with a diffuse organization of this putative receptor on the cell surface in presumably labile adhesions, whereas stationary cells were anchored to the substratum at specific sites linked to the cytoskeleton near local concentrations of FN-receptor.
Collapse
|
18
|
Keller RE. The cellular basis of amphibian gastrulation. DEVELOPMENTAL BIOLOGY (NEW YORK, N.Y. : 1985) 1986; 2:241-327. [PMID: 3078116 DOI: 10.1007/978-1-4613-2141-5_7] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- R E Keller
- Department of Zoology, University of California, Berkeley 94720
| |
Collapse
|
19
|
McKinney RV, Steflik DE, Koth DL. Evidence for a junctional epithelial attachment to ceramic dental implants. A transmission electron microscopic study. J Periodontol 1985; 56:579-91. [PMID: 3863908 DOI: 10.1902/jop.1985.56.10.579] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The interface of the crevicular gingiva with the surface of a dental implant is a critical zone representing the potential biological seal which protects the underlying bone and soft tissue-supporting mechanisms from destructive extraneous substances. Ultrastructural examination of regenerated junctional epithelial cells interfacing surgically placed endosteal dental implants, comprised of alpha-alumina oxide ceramic in single crystalline form, exhibited an external basal lamina and linear body located between the external surface epithelial cell and the implant. In addition, hemidesmosomes were located at intervals along the outer junctional epithelial plasma membrane. The component substructures of the basal lamina and the hemidesmosomes were similar to those seen interfacing natural teeth. The linear body was an electron-dense structure between the lamina densa and the inert biomaterial. This study provides ultrastructural evidence for the presence of an attachment complex between gingiva and aluminum oxide implants which is analogous to that seen around natural teeth. These data support concept that a viable biological seal can develop around endosteal dental implants and provide support for satisfactory clinical service.
Collapse
|
20
|
Damsky CH, Knudsen KA, Bradley D, Buck CA, Horwitz AF. Distribution of the cell substratum attachment (CSAT) antigen on myogenic and fibroblastic cells in culture. J Cell Biol 1985; 100:1528-39. [PMID: 3921554 PMCID: PMC2113851 DOI: 10.1083/jcb.100.5.1528] [Citation(s) in RCA: 245] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Previous studies (Neff et al., 1982, J. Cell. Biol. 95:654-666; Decker et al., 1984. J. Cell. Biol. 99:1388-1404) have described a monoclonal antibody (CSAT Mab) directed against a complex of three integral membrane glycoproteins of 120,000-160,000 mol wt (CSAT antigen [ag]) involved in the cell matrix adhesion of myoblasts and fibroblasts. In localization studies on fibroblasts presented here, CSAT ag has a discrete, well-organized distribution pattern. It co-aligns with portions of stress fibers and is enriched at the periphery of, but not directly beneath vinculin-rich focal contacts. In this last location, it co-distributes with fibronectin, consistent with the suggestion that the CSAT ag participates in the mechanism by which fibroblasts attach to fibronectin. In prefusion myoblasts, which are rapidly detached by CSAT Mab, CSAT ag is distributed diffusely as are vinculin, laminin, and fibronectin. After fusion, myotubes become more difficult to detach with CSAT Mab. The CSAT ag and vinculin are organized in a much more discrete pattern on the myotube surface, becoming enriched at microfilament bundle termini and in lateral lamellae which appear to attach myotubes to the substratum. These results suggest that the organization of CSAT ag-adhesive complexes on the surface of myogenic cells can affect the stability of their adhesive contacts. We conclude from the sum of the studies presented that, in both myogenic and fibroblastic cells, the CSAT ag is localized in sites expected of a surface membrane mediator of cell adhesion to extracelluon of CSAT ag-adhesive complexes on the surface of myogenic cells can affect the stability of their adhesive contacts. We conclude from the sum of the studies presented that, in both myogenic and fibroblastic cells, the CSAT ag is localized in sites expected of a surface membrane mediator of cell adhesion to extracellular matrix. The results from studies that use fibroblasts in particular suggest the involvement of CSAT ag in the adhesion of these cells to fibronectin.
Collapse
|
21
|
Chen WT, Hasegawa E, Hasegawa T, Weinstock C, Yamada KM. Development of cell surface linkage complexes in cultured fibroblasts. J Biophys Biochem Cytol 1985; 100:1103-14. [PMID: 3884631 PMCID: PMC2113771 DOI: 10.1083/jcb.100.4.1103] [Citation(s) in RCA: 265] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The possible role of a 140K membrane-associated protein complex (140K) in fibronectin-cytoskeleton associations has been examined. The 140K was identified by the monoclonal antibody JG22E. Monoclonal and polyclonal antibodies to the 140K showed identical patterns of binding to the cell membranes of fixed and permeabilized chicken embryonic fibroblasts; localization was diffuse, but with marked concentration in cell-to-extracellular matrix contact sites. Correlative localization with interference reflection microscopy and double-label or triple-label immunofluorescence showed that 140K co-distributed with extracellular fibronectin fibrils and intracellular alpha-actinin in microfilament bundles at extracellular matrix contact sites but tended not to co-localize with tropomyosin present in bundles at sites farther from adhesion sites. In addition, binding of antibodies to 140K, alpha-actinin, and fibronectin was excluded from vinculin-rich focal adhesion sites at the cellular periphery. A progressive development of cell surface alpha-actinin-140K-fibronectin associations was observed in early spreading cells. The anti-140K monoclonal antibody JG22E inhibited the attachment and spreading of both normal and Rous sarcoma virus-transformed chicken embryonic fibroblasts to a fibronectin substratum. However, the anti-140K monoclonal antibody became a positive mediator of cell attachment and spreading if it was adsorbed or cross-linked to the substratum. Our results provide the first description of a membrane-associated protein complex that co-localizes with fibronectin and microfilament bundles, and they suggest that the 140K complex may be part of a cell surface linkage between fibronectin and the cytoskeleton.
Collapse
|
22
|
A polyoma mutant that encodes small T antigen but not middle T antigen demonstrates uncoupling of cell surface and cytoskeletal changes associated with cell transformation. Mol Cell Biol 1985. [PMID: 6098822 DOI: 10.1128/mcb.4.12.2774] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The hr-t gene of polyoma virus encodes both the small and middle T (tumor) antigens and exerts pleiotropic effects on cells. By mutating the 3' splice site for middle T mRNA, we have constructed a virus mutant, Py808A, which fails to express middle T but encodes normal small and large T proteins. The mutant failed to induce morphological transformation or growth in soft agar, but did stimulate postconfluent growth of normal cells. Cells infected by Py808A became fully agglutinable by lectins while retaining normal actin cable architecture and normal levels of extracellular fibronectin. These properties of Py808A demonstrated the separability of structural changes at the cell surface from those in the cytoskeleton and extracellular matrix, parameters which have heretofore been linked in the action of the hr-t and other viral oncogenes.
Collapse
|
23
|
Liang TJ, Carmichael GG, Benjamin TL. A polyoma mutant that encodes small T antigen but not middle T antigen demonstrates uncoupling of cell surface and cytoskeletal changes associated with cell transformation. Mol Cell Biol 1984; 4:2774-83. [PMID: 6098822 PMCID: PMC369288 DOI: 10.1128/mcb.4.12.2774-2783.1984] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The hr-t gene of polyoma virus encodes both the small and middle T (tumor) antigens and exerts pleiotropic effects on cells. By mutating the 3' splice site for middle T mRNA, we have constructed a virus mutant, Py808A, which fails to express middle T but encodes normal small and large T proteins. The mutant failed to induce morphological transformation or growth in soft agar, but did stimulate postconfluent growth of normal cells. Cells infected by Py808A became fully agglutinable by lectins while retaining normal actin cable architecture and normal levels of extracellular fibronectin. These properties of Py808A demonstrated the separability of structural changes at the cell surface from those in the cytoskeleton and extracellular matrix, parameters which have heretofore been linked in the action of the hr-t and other viral oncogenes.
Collapse
|
24
|
|
25
|
Chen WT, Olden K, Bernard BA, Chu FF. Expression of transformation-associated protease(s) that degrade fibronectin at cell contact sites. J Biophys Biochem Cytol 1984; 98:1546-55. [PMID: 6325472 PMCID: PMC2113210 DOI: 10.1083/jcb.98.4.1546] [Citation(s) in RCA: 137] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Virus-transformed fibroblasts show an increased production of proteases as well as loss of extracellular adhesive proteins. To determine whether these transformation-associated events are related, we investigated the capacity of Rous sarcoma virus-transformed cells (embryonic chick fibroblasts and mouse BALB/c 3T3) to degrade fibronectin by using a novel cross-linked protein substratum: fluorescence-labeled or radiolabeled fibronectin covalently linked to the surface of a fixed gelatin film. In serum-containing medium, the coupled fibronectin was not released when incubated without cells, and only a small amount was released when incubated with nontransformed cells. However, when transformed cells were seeded on the radiolabeled fibronectin-coupled substratum, there was a threefold increase in the time-dependent release of radioactivity into the medium. The released material was characterized as peptides with molecular sizes of less than 30,000 daltons. Correspondingly, growth of transformed cells on the rhodamine-fibronectin substratum resulted in the appearance of discrete negative fluorescent spots beneath the cells and along their migratory paths, whereas a uniform fluorescent carpet was detected with nontransformed cells. The release of radioactivity was partially inhibited by protease inhibitors, including alpha 2-macroglobulin, leupeptin, and benzamidine, but the negative fluorescent spots appeared unaffected by any of these inhibitors. However, both the release of radiolabeled peptides and the appearance of fluorescence-negative spots were inhibited by 1,10-phenanthroline at concentrations that did not affect cellular attachment and protein synthesis, thus supporting a role for proteases in localized degradation of fibronectin substratum. These fluorescence-negative spots coincided with sites of fibronectin disappearance as judged by indirect labeling with antibodies to cellular fibronectin. In addition, immunofluorescent analyses showed a correlation between vinculin localization and the negative fibronectin spots found under transformed cells, indicating that degradation occurs at cell substratum contact sites. These results can be correlated with other transformation-associated phenotypic changes, and are discussed in terms of the invasion of tumor cells into the extracellular matrix.
Collapse
|
26
|
References. Mol Aspects Med 1984. [DOI: 10.1016/b978-0-08-033239-0.50027-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
27
|
Cooper MS, Keller RE. Perpendicular orientation and directional migration of amphibian neural crest cells in dc electrical fields. Proc Natl Acad Sci U S A 1984; 81:160-4. [PMID: 6582473 PMCID: PMC344630 DOI: 10.1073/pnas.81.1.160] [Citation(s) in RCA: 107] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The behavior of cultured neural crest cells of Ambystoma mexicanum and Xenopus laevis in dc electrical fields was studied. In fields of 1-5 V/cm, isolated or confluent cells retract both their anode- and cathode-facing margins. Subsequently, the cells elongate, with protrusive activity confined to their narrow ends. In larger fields (greater than or equal to 5 V/cm), protrusions form on the cathode-facing sides of the perpendicularly oriented cells. The cells then begin migrating laterally, perpendicular to their long axes, towards the cathode. We suggest that the perpendicular alignment and cathode-directed migrations result from cytoskeletal changes mediated by modified ion fluxes through the anode-facing (hyperpolarized) and cathode-facing (depolarized) cell membranes. The breaking of cellular confluence in response to dc electric fields is also discussed.
Collapse
|
28
|
Geiger B, Avnur Z, Kreis TE, Schlessinger J. The dynamics of cytoskeletal organization in areas of cell contact. CELL AND MUSCLE MOTILITY 1984; 5:195-234. [PMID: 6423268 DOI: 10.1007/978-1-4684-4592-3_5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
29
|
Chapman AE. Characterization of a 140Kd cell surface glycoprotein involved in myoblast adhesion. J Cell Biochem 1984; 25:109-21. [PMID: 6384244 DOI: 10.1002/jcb.240250206] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Two monoclonal antibodies that cause changes in the morphology of cultured chick myogenic cells have been described previously [8]. In this paper, these antibodies are shown to interact with the same 140Kd protein. The 140Kd protein has been further characterized as a cell-surface glycoprotein by lactoperoxidase-catalyzed iodinations and lectin affinity chromatography. The protein is resistant to digestion by trypsin and collagenase and has been shown to be unrelated to fibronectin by immunoprecipitation studies and by peptide mapping. A second protein, of approximately 170Kd MW, is also immunoprecipitated by the monoclonal antibodies. This protein is probably unrelated to the 140Kd protein since the peptide maps are quite distinct.
Collapse
|
30
|
Hedman K, Christner J, Julkunen I, Vaheri A. Chondroitin sulfate at the plasma membranes of cultured fibroblasts. J Biophys Biochem Cytol 1983; 97:1288-93. [PMID: 6413515 PMCID: PMC2112601 DOI: 10.1083/jcb.97.4.1288] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
We have previously shown that in confluent human fibroblast cultures chondroitin sulfate proteoglycan is a component of the fibronectin-containing pericellular matrix fibers. In the present work the distribution of chondroitin sulfate was studied in subconfluent cell cultures using antibodies that bind to a chemically defined carbohydrate fragment of chondroitinase ABC-modified chondroitin sulfate proteoglycan. Using immunofluorescence microscopy, we observed, in addition to the fibrillar matrix staining, chondroitin sulfate diffusely distributed at the cell surface. In indirect immunoferritin electron microscopy this staining corresponded to patchy binding of ferritin close (24 nm) to the outer aspect of the plasma membrane. The patchy organization appeared uniform in all cell surfaces. The cell surface chondroitin sulfate could not be removed from the plasma membrane by agents that dissociate electrostatic interactions. These data show that in fibroblasts chondroitin sulfate is a component of the outer aspect of the plasma membrane, and raise the possibility of an integral plasma membrane chondroitin sulfate proteoglycan.
Collapse
|
31
|
Cole GJ, Elam JS. Characterization of axonally transported glycoproteins in regenerating garfish olfactory nerve. J Neurochem 1983; 41:691-702. [PMID: 6875560 DOI: 10.1111/j.1471-4159.1983.tb04796.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This study examined changes in composition and concanavalin A (Con A) binding of axonally transported glycoproteins and their pronase-generated glycopeptides in regenerating garfish olfactory nerve. A previous study had demonstrated a regeneration-related increase in the proportion of [3H]glucosamine label in lower-molecular-weight Con A-binding glycopeptides derived from transported glycoproteins. Further analysis of carbohydrate composition shows that these molecules resemble mannose-rich oligosaccharides in composition and are increased in absolute amount in regenerating nerve. Subcellular analysis shows that the Con A-binding glycopeptides are enriched in membrane subfractions, particularly in a high-density fraction that morphologically resembles isolated cell surface coat. Regeneration-related changes in intact axonally transported glycoproteins were also detected. Sodium dodecyl sulfate gel electrophoresis of transport-labeled glycoproteins disclosed growth-correlated increases in radioactivity associated with 180-200K, 105-115K, and 80-90K components, while a 150-160K molecular weight class of glycoproteins was diminished in relative labeling. Intact glycoproteins displaying an affinity for Con A were also augmented in regenerating nerve, the increases occurring primarily in molecules in the 50-140K range.
Collapse
|
32
|
Priestley GC, Adams LW. Hyperactivity of fibroblasts cultured from psoriatic skin: I. Faster proliferation and effect of serum withdrawal. Br J Dermatol 1983; 109:149-56. [PMID: 6871094 DOI: 10.1111/j.1365-2133.1983.tb07075.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Fibroblasts were cultured from the involved and uninvolved forearm skin of patients with severe generalized psoriasis and compared with those from the forearms of normal controls of similar ages. Thirteen strains were obtained from involved skin (PSA strains) and sixteen strains from uninvolved skin (PSB), with thirteen control strains (NSF). Outgrowth of fibroblasts from the psoriatic skin explants was slightly quicker than from control skin and the average proliferation rates of passaged strains were PSA 144, PSB 134 and NSF 94 (P less than 0.05). Psoriatic fibroblasts were abnormally dependent on serum for anchorage. In serum-free medium many cells rounded up and were only loosely attached to the substratum. This effect was rapid, reversible and not corrected by adding fibronectin. Cell attachment assays showed only small differences between the psoriatic and normal fibroblasts and the main effect of serum withdrawal appeared to be on spreading rather than attachment. These data suggest that the dermis of both involved and uninvolved psoriatic skin is abnormal and that the hyperactivity persists in vitro. Our findings seem most compatible with a hyperproliferative reaction of both epidermis and dermis to an extracutaneous, perhaps vascular, stimulus.
Collapse
|
33
|
Swafford JR, Malloy PJ, Reeves HC. Immunochemical localization of NADP-specific isocitrate dehydrogenase in Escherichia coli. Science 1983; 221:295-6. [PMID: 6344223 DOI: 10.1126/science.6344223] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The intracellular localization of isocitrate dehydrogenase was determined by immunochemical techniques with ultrathin sections of Escherichia coli. The thin sections, which were obtained by ultracryomicrotomy, were incubated first with antiserum specific for the enzyme and then with a protein A-gold complex. Transmission electron microscopy showed that the gold label was dispersed mainly in the cytoplasm.
Collapse
|
34
|
Altered cell spreading in cytochalasin B: a possible role for intermediate filaments. Mol Cell Biol 1983. [PMID: 6298602 DOI: 10.1128/mcb.3.1.113] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trypsinized chicken embryo dermal fibroblasts plated in the presence of cytochalasin B (CB) quickly attached to the substrate and within 24 h obtained an arborized morphology. This morphology is the result of the pushing out of pseudopodial processes along the substrate from the round central cell body. There were no microfilament bundles in the processes of these cells plated in the presence of CB; however, the processes were packed with highly oriented, parallel-aligned intermediate filaments. Only a few scattered microtubules were seen in these processes. These results demonstrated that in CB, cells are capable of a form of movement, i.e., the extension of pseudopodial processes, without the presence of the microfilament structures usually associated with extensions of the cytoplasm and pseudopodial movements. We also found that arborization did not depend on fibronectin since cells plated in CB did not have fibronectin fibers associated with the processes. Chicken fibroblasts transformed with tsLA24A, a Rous sarcoma virus which is temperature sensitive for pp60src, formed arborized cells with properties similar to those of uninfected fibroblasts when plated in the presence of CB at the nonpermissive temperature (41 degrees C). At the permissive temperature for transformation (36 degrees C), the cells attached to the substrate but remained round. These round cells were not only deficient in microfilament bundles but also lacked the highly organized intermediate filaments found in the processes of the arborized cells at 41 degrees C. Although both microfilament bundles and the fibronectin matrix were decreased after transformation with Rous sarcoma virus, neither was involved in the formation of processes in normal cells plated in CB. Therefore, the inability of the transformed cells to form or maintain processes in CB must be the result of another structural alteration in the transformed cells, such as that of the intermediate filaments.
Collapse
|
35
|
Couchman JR, Höök M, Rees DA, Timpl R. Adhesion, growth, and matrix production by fibroblasts on laminin substrates. J Cell Biol 1983; 96:177-83. [PMID: 6681817 PMCID: PMC2112271 DOI: 10.1083/jcb.96.1.177] [Citation(s) in RCA: 165] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Human embryonic skin fibroblasts have been shown to attach and spread on laminin substrates in the absence of protein synthesis and presence of fibronectin-depleted serum and anti-fibronectin antibodies. Rates of attachment and the type of spreading are virtually identical on fibronectin and laminin-coated substrates with the development of microfilament bundles and focal adhesions. Antibodies to laminin, but not fibronectin, will prevent or reverse fibroblast adhesion to laminin, whereas antibodies to fibronectin but not laminin will give similar results on fibronectin-coated substrates. These and other results indicate that fibroblasts possess distinct receptors for laminin and fibronectin which on contact with suitable substrates promote adhesion through interaction with common intermediates. This type of adhesion is compatible with subsequent growth and extracellular matrix production.
Collapse
|
36
|
Maher P, Singer SJ. A 200-kd protein isolated from the fascia adherens membrane domains of chicken cardiac muscle cells is detected immunologically in fibroblast focal adhesions. CELL MOTILITY 1983; 3:419-29. [PMID: 6362888 DOI: 10.1002/cm.970030510] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
On the premise that the fascia adherens of cardiac muscle cell intercalated disk membranes is a structure that is closely homologous to the focal adhesions formed by fibroblasts, a fascia adherens preparation was isolated from chicken cardiac muscle, and was analyzed for its protein composition. A prominent 200-kilodalton (kd) protein was purified from the fascia preparation and shown to be antigenically unrelated to several previously characterized cytoskeletal proteins, including cardiac myosin and vinculin. With monospecific antibodies to the 200-kd protein, an identical or closely similar intracellular protein was shown to be associated with the focal adhesion plaques of fibroblasts.
Collapse
|
37
|
Menko AS, Toyama Y, Boettiger D, Holtzer H. Altered cell spreading in cytochalasin B: a possible role for intermediate filaments. Mol Cell Biol 1983; 3:113-25. [PMID: 6298602 PMCID: PMC368508 DOI: 10.1128/mcb.3.1.113-125.1983] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Trypsinized chicken embryo dermal fibroblasts plated in the presence of cytochalasin B (CB) quickly attached to the substrate and within 24 h obtained an arborized morphology. This morphology is the result of the pushing out of pseudopodial processes along the substrate from the round central cell body. There were no microfilament bundles in the processes of these cells plated in the presence of CB; however, the processes were packed with highly oriented, parallel-aligned intermediate filaments. Only a few scattered microtubules were seen in these processes. These results demonstrated that in CB, cells are capable of a form of movement, i.e., the extension of pseudopodial processes, without the presence of the microfilament structures usually associated with extensions of the cytoplasm and pseudopodial movements. We also found that arborization did not depend on fibronectin since cells plated in CB did not have fibronectin fibers associated with the processes. Chicken fibroblasts transformed with tsLA24A, a Rous sarcoma virus which is temperature sensitive for pp60src, formed arborized cells with properties similar to those of uninfected fibroblasts when plated in the presence of CB at the nonpermissive temperature (41 degrees C). At the permissive temperature for transformation (36 degrees C), the cells attached to the substrate but remained round. These round cells were not only deficient in microfilament bundles but also lacked the highly organized intermediate filaments found in the processes of the arborized cells at 41 degrees C. Although both microfilament bundles and the fibronectin matrix were decreased after transformation with Rous sarcoma virus, neither was involved in the formation of processes in normal cells plated in CB. Therefore, the inability of the transformed cells to form or maintain processes in CB must be the result of another structural alteration in the transformed cells, such as that of the intermediate filaments.
Collapse
|
38
|
Neff NT, Lowrey C, Decker C, Tovar A, Damsky C, Buck C, Horwitz AF. A monoclonal antibody detaches embryonic skeletal muscle from extracellular matrices. J Biophys Biochem Cytol 1982; 95:654-66. [PMID: 6183279 PMCID: PMC2112965 DOI: 10.1083/jcb.95.2.654] [Citation(s) in RCA: 252] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
We have described a monoclonal antibody that rounds and detaches chick skeletal myoblasts and myotubes from extracellular substrata. The antibody also inhibits the attachment of myogenic cells to a gelatin-coated substratum but has no detectable effect on myoblast fusion. The cellular response to antibody treatment varies with differentiation and cell type. Young myoblasts and myotubes are rapidly rounded and detached by the antibody. Older myotubes require longer incubation times or higher antibody titers for rounding and detachment. Chick embryo fibroblasts, cardiac cells, and neurons are not similarly rounded and remain attached. Since the antibody also detaches cells from embryonic muscle tissue explants, the cell-substratum interaction perturbed by the antibody appears relevant to the in vivo interaction of myogenic cells with their extracellular matrices. Binding studies using iodinated antibody revealed 2-4 x 10(5) sites per myoblast with an apparent Kd in the range of 2-5 x 10(-9) molar. Embryo fibroblasts bind antibody as well and display approximately twice the number of binding sites per cell. The fluorescence distribution of antigen on myoblasts and myotubes is somewhat punctate and particularly bright along the edge of the myotube. The distribution on fibroblasts was also punctate and was particularly bright along the cell periphery and portions of stress fibers. For both cell types the binding was distinctly different than that reported for collagen, fibronectin, and other extracellular molecules. The antigen, as isolated by antibody affinity chromatography, inhibits antibody-induced rounding. SDS PAGE reveals two unique polypeptides migrating in the region of approximately 120 and 160 kilodaltons (kd). The most straightforward mechanism for the antibody-induced rounding and detachment is the perturbation of a membrane molecule involved in adhesion. The hypothesized transmembrane link between extracellular macromolecules and the cytoskeleton provides an obvious candidate.
Collapse
|
39
|
Chen WT, Singer SJ. Immunoelectron microscopic studies of the sites of cell-substratum and cell-cell contacts in cultured fibroblasts. J Cell Biol 1982; 95:205-22. [PMID: 6815205 PMCID: PMC2112341 DOI: 10.1083/jcb.95.1.205] [Citation(s) in RCA: 301] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Our object was to obtain information about the molecular structures present at cell-substratum and cell-cell contact sites formed by cultured fibroblasts. We have carried out double immunoelectron-microscopic labeling experiments on ultrathin frozen sections cut through such contact sites to determine the absolute and relative dispositions of the three proteins fibronectin, vinculin, and alpha-actinin with respect to these sites. (a) Three types of cell-substratum and cell-cell contact sites familiar from plastic sections could also be discriminated in the frozen sections by morphological criteria alone, i.e., the gap distances between the two surfaces, and the presence of submembranous densities. These types were: (i) focal adhesions (FA); (ii) close contacts (CC); and (iii) extracellular matrix contacts (ECM). This morphological typing of the contact sites allowed us to recognize and assign distinctive immunolabeling patterns for the three proteins to each type of site on the frozen sections. (b) FA sites were immunolabeled intracellularly for vinculin and alpha-actinin, with vinculin labeling situated closer to the membrane than alpha-actinin. Fibronectin was not labeled in the narrow gap between the cell surface and the substratum, or between two cells, at FA sites. Control experiments showed that this could not be ascribed to inaccessibility of the FA narrow gap to the immunolabeling reagents but indicated an absence or severe depletion of fibronectin from these sites. (c) CC sites were labeled intracellularly for alpha-actinin but not vinculin and were labeled extracellularly for fibronectin. (d) ECM sites were characterized by large separations (often greater than 100 nm) between the cell and substratum or between two cells, which were connected by long cables of extracellular matrix components, including fibronectin. In late (24-36 h) cultures, ECM contacts predominated over the other types. ECM sites appeared to be of two kinds, one labeled intracellularly for both alpha-actinin and vinculin, the other for alpha-actinin alone. (e) From these and other results, a coherent but tentative scheme is proposed for the molecular ultrastructure of these contacts sites, and specific functional roles are suggested for fibronectin, vinculin, and alpha-actinin in cell adhesion and in the linkage of intracellular microfilaments to membranes at the different types of contact sites.
Collapse
|
40
|
|
41
|
Virtanen I, Vartio T, Badley RA, Lehto VP. Fibronectin in adhesion, spreading and cytoskeletal organization of cultured fibroblasts. Nature 1982; 298:660-3. [PMID: 6808395 DOI: 10.1038/298660a0] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
42
|
Couchman JR, Rees DA, Green MR, Smith CG. Fibronectin has a dual role in locomotion and anchorage of primary chick fibroblasts and can promote entry into the division cycle. J Cell Biol 1982; 93:402-10. [PMID: 6178746 PMCID: PMC2112840 DOI: 10.1083/jcb.93.2.402] [Citation(s) in RCA: 132] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Fibronectin (FN), which is already known to be a natural factor for fibroblast spreading on substrata, has now been shown to be essential for two distinct types of adhesion with different biological functions in chick heart fibroblasts, namely adhesion directed toward locomotion and toward stationary anchorage for growth. Manipulation of culture conditions and the use of antisera of differing specificities has demonstrated that both exogenous and cell-derived FN are important in each process. The organization of the fibronectin-containing matrix differs between the two states. Immunoelectron microscopy with a colloidal gold marker reveals the presence of small membrane-associated plaques of fibronectin in motile cells with associated submembranous specialization. A fibrillar matrix containing fibronectin is dominant in nonmotile, growing fibroblasts. The development of focal adhesions for stationary anchorage can be dramatically enhanced by addition of cell-derived FN at an appropriate stage, and this promotes entry into the growth cycle. New macromolecular synthesis in addition to FN is necessary for focal adhesion development but not for locomotion.
Collapse
|
43
|
Carter WG. The cooperative role of the transformation-sensitive glycoproteins, GP140 and fibronectin, in cell attachment and spreading. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)81103-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
44
|
Singer II. Association of fibronectin and vinculin with focal contacts and stress fibers in stationary hamster fibroblasts. J Cell Biol 1982; 92:398-408. [PMID: 6801062 PMCID: PMC2112091 DOI: 10.1083/jcb.92.2.398] [Citation(s) in RCA: 123] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We have recently observed a transmembrane association between extracellular fibronectin (FN) fibers and elongated focal patches or fibers of vinculin (VN) in G1-arrested stationary Nil 8 hamster fibroblasts, with double-label immunofluorescence microscopy (Singer and Paradiso, 1981, Cell. 24:481-492). We hypothesized that these FN-VN complexes might correspond to focal contacts, the membrane sites that are probably mainly responsible for attaching cells to their substrata, because vinculin is often localized in focal contacts. However, because fibronectin-vinculin associations may not be restricted to the substrate adhesive surface of the cell, it became necessary to determine whether some or all of the various kinds of FN-VN complexes which we described are in proximity to the substrate. Using interference reflection optics and double-label immunofluorescence microscopy for fibronectin and vinculin, many elongated (up to 38 micrometer) FN-VN associations were found to be strikingly coincident with focal contacts in the perinuclear area of extremely flattened arrested Nil 8 fibroblasts in 0.3% fetal bovine serum (FBS). In addition, the long FN-VN adhesion complexes were precisely aligned with the major phase-dense stress fibers observed at the ventral surfaces of these stationary cells with phase contrast microscopy. Fibronectin was neither associated with vinculin-containing focal contacts of Nil 8 cells cultured in medium with 5% FBS nor with vinculin-negative focal contacts located at the extreme edges of stationary cells arrested in 0.3 FBS. Our time-course experiments suggest that early FN-VN lacking-focal contacts, which form at the cellular margins, develop into mature substrate adhesion complexes containing both fibronectin and vinculin, localized in the major stress fibers at the centers of sessile fibroblasts.
Collapse
|
45
|
Damsky CH, Knudsen KA, Buck CA. Integral membrane glycoproteins related to cell-substratum adhesion in mammalian cells. J Cell Biochem 1982; 18:1-13. [PMID: 7068775 DOI: 10.1002/jcb.1982.240180102] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Broad spectrum antisera have been raised against surface membrane-derived material from baby hamster kidney cells and mouse mammary tumor epithelial cells. These antisera disrupt cell-substratum adhesion in their respective cell types. Using an antibody neutralization (blocking) assay, adhesion-related glycoproteins have been isolated from non-ionic detergent extracts of each cell type. The purified material in each case consisted of a restricted population of glycoproteins of approximately 120,000-160,000 Mr. Purified material from each system blocked the disruption of adhesion induced by the heterologous antiserum on either cell type. The antisera were capable of disrupting cell-substratum adhesion of a large number of cell types and species sources. In addition, antibody blocking activity could be detected from partially purified extracts of several adult hamster cell types and a variety of cultured cell types. Thus, in addition to having similar substratum-associated glycoproteins ((eg, fibronectin) and cytoskeleton-associated proteins (eg, alpha-actinin and vinculin) cells from different species and tissue sources appear to have a relatively conserved class of integral membrane glycoproteins involved in cell substratum-adhesion.
Collapse
|
46
|
Knudsen KA, Damsky CH, Buck CA. Expression of adhesion-related membrane components in adherent versus nonadherent hamster melanoma cells. J Cell Biochem 1982; 18:157-67. [PMID: 7068778 DOI: 10.1002/jcb.1982.240180204] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The existence of integral membrane components that are involved in cell-substratum adhesion has been postulated. Using an immunochemical approach developed in this laboratory, we provide further evidence for the role in cell-substratum adhesion of integral membrane glycoproteins within a molecular weight region of 120,000-140,000. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of material enriched approximately 100-fold in adhesion-related components revealed the 120,000-140,000 Mr glycoproteins in an adherent hamster melanoma cell line. These glycoproteins are greatly reduced in a nonadherent variant. Induction of adhesion in these cells by exposure to BudR is accompanied by re-expression of the surface adhesion antigens.
Collapse
|
47
|
|
48
|
|
49
|
Geiger B, Dutton AH, Tokuyasu KT, Singer SJ. Immunoelectron microscope studies of membrane-microfilament interactions: distributions of alpha-actinin, tropomyosin, and vinculin in intestinal epithelial brush border and chicken gizzard smooth muscle cells. J Cell Biol 1981; 91:614-28. [PMID: 6799520 PMCID: PMC2112792 DOI: 10.1083/jcb.91.3.614] [Citation(s) in RCA: 345] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The ultrastructural localization of three cytoskeletal proteins, alpha-actinin, tropomyosin, and vinculin, in the brush border of epithelial cells of chicken small intestine and the smooth muscle cells of chicken gizzard was studied by immunofluorescence and immunonelectron microscope labeling of frozen sections of lightly fixed, intact tissues. In the immunoelectron microscope studies, a recently described new type of electron-dense antibody conjugate, imposil-antibody, has been successfully used, along with ferritin-antibody conjugates, in single and double immunolabeling experiments. In the intestinal brush border shows that vinvulin is sharply confined to the junctional complex close to the membrane region of the zonula adherens, in distinct contrast to the more diffuse distributions of the other two proteins. In the smooth muscle cells, the labeling patterns show that vinculin is sharply confined to the membrane-associated dense plaques, closer to the membrane than the alpha-Actinin is also present in the cytoplastic dense bodies, from which vinculin is absent. Tropomyosin is present diffusely distributed in the cytoplasm, but absent from both dense plaques and dense bodies. These findings with the muscle cells demonstrate, therefore, that the dense plaques and dense bodies are chemically and structurally distinct entities. The results with both tissues, along with those in previous papers (Geiger, 1979, Cell. 18:193-205.; Geiger et al., 1980, Proc. Natl. Acad. Sci. U. S. A. 77:4127-4131), suggest that vinculin may play an important and widespread role in the linkage of actin-containing microfilament bundles to membranes.
Collapse
|
50
|
Koteliansky VE, Glukhova MA, Morozkin AD, Musatov AP, Shirinsky VP, Tskhovrebova LA, Smirnov VN. A study of actin-fibronectin interaction. FEBS Lett 1981; 133:31-5. [PMID: 7308472 DOI: 10.1016/0014-5793(81)80464-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|