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Garrigues HJ, DeMaster LK, Rubinchikova YE, Rose TM. KSHV attachment and entry are dependent on αVβ3 integrin localized to specific cell surface microdomains and do not correlate with the presence of heparan sulfate. Virology 2014; 464-465:118-133. [PMID: 25063885 DOI: 10.1016/j.virol.2014.06.035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/02/2014] [Accepted: 06/27/2014] [Indexed: 11/16/2022]
Abstract
Cellular receptors for KSHV attachment and entry were characterized using tyramide signal amplification (TSA)-enhanced confocal microscopy. Integrins αVβ3, αVβ5 and α3β1 were detected on essentially all the actin-based cell surface microdomains that initially bind KSHV, while the presence of CD98 and heparan sulfate (HS), the putative attachment receptor, was more variable. KSHV bound to the same cell surface microdomains with and without HS indicating that initial attachment of KSHV is not dependent on HS and that receptors other than HS can mediate attachment. A human salivary gland (HSG) epithelial line was identified, which lacks αVβ3 but expresses high levels of HS, α3β1 and other putative KSHV receptors. These cells were resistant to KSHV binding and infection. Reconstitution of cell surface αVβ3 rendered HSG cells highly susceptible to KSHV infection, demonstrating a critical role for αVβ3 in the binding and entry of KSHV that is not shared with other proposed receptors.
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Affiliation(s)
- H Jacques Garrigues
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA.
| | - Laura K DeMaster
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | - Yelena E Rubinchikova
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA.
| | - Timothy M Rose
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA; Department of Pediatrics, University of Washington, Seattle, WA 98195, USA.
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KSHV cell attachment sites revealed by ultra sensitive tyramide signal amplification (TSA) localize to membrane microdomains that are up-regulated on mitotic cells. Virology 2014; 452-453:75-85. [PMID: 24606685 DOI: 10.1016/j.virol.2014.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 11/28/2013] [Accepted: 01/07/2014] [Indexed: 11/24/2022]
Abstract
Cell surface structures initiating attachment of Kaposi's sarcoma-associated herpesvirus (KSHV) were characterized using purified hapten-labeled virions visualized by confocal microscopy with a sensitive fluorescent enhancement using tyramide signal amplification (TSA). KSHV attachment sites were present in specific cellular domains, including actin-based filopodia, lamellipodia, ruffled membranes, microvilli and intercellular junctions. Isolated microdomains were identified on the dorsal surface, which were heterogeneous in size with a variable distribution that depended on cellular confluence and cell cycle stage. KSHV binding domains ranged from scarce on interphase cells to dense and continuous on mitotic cells, and quantitation of bound virus revealed a significant increase on mitotic compared to interphase cells. KSHV also bound to a supranuclear domain that was distinct from microdomains in confluent and interphase cells. These results suggest that rearrangement of the cellular membrane during mitosis induces changes in cell surface receptors implicated in the initial attachment stage of KSHV entry.
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Schwartz MP, Rogers RE, Singh SP, Lee JY, Loveland SG, Koepsel JT, Witze ES, Montanez-Sauri SI, Sung KE, Tokuda EY, Sharma Y, Everhart LM, Nguyen EH, Zaman MH, Beebe DJ, Ahn NG, Murphy WL, Anseth KS. A quantitative comparison of human HT-1080 fibrosarcoma cells and primary human dermal fibroblasts identifies a 3D migration mechanism with properties unique to the transformed phenotype. PLoS One 2013; 8:e81689. [PMID: 24349113 PMCID: PMC3857815 DOI: 10.1371/journal.pone.0081689] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 10/25/2013] [Indexed: 01/09/2023] Open
Abstract
Here, we describe an engineering approach to quantitatively compare migration, morphologies, and adhesion for tumorigenic human fibrosarcoma cells (HT-1080s) and primary human dermal fibroblasts (hDFs) with the aim of identifying distinguishing properties of the transformed phenotype. Relative adhesiveness was quantified using self-assembled monolayer (SAM) arrays and proteolytic 3-dimensional (3D) migration was investigated using matrix metalloproteinase (MMP)-degradable poly(ethylene glycol) (PEG) hydrogels (“synthetic extracellular matrix” or “synthetic ECM”). In synthetic ECM, hDFs were characterized by vinculin-containing features on the tips of protrusions, multipolar morphologies, and organized actomyosin filaments. In contrast, HT-1080s were characterized by diffuse vinculin expression, pronounced β1-integrin on the tips of protrusions, a cortically-organized F-actin cytoskeleton, and quantitatively more rounded morphologies, decreased adhesiveness, and increased directional motility compared to hDFs. Further, HT-1080s were characterized by contractility-dependent motility, pronounced blebbing, and cortical contraction waves or constriction rings, while quantified 3D motility was similar in matrices with a wide range of biochemical and biophysical properties (including collagen) despite substantial morphological changes. While HT-1080s were distinct from hDFs for each of the 2D and 3D properties investigated, several features were similar to WM239a melanoma cells, including rounded, proteolytic migration modes, cortical F-actin organization, and prominent uropod-like structures enriched with β1-integrin, F-actin, and melanoma cell adhesion molecule (MCAM/CD146/MUC18). Importantly, many of the features observed for HT-1080s were analogous to cellular changes induced by transformation, including cell rounding, a disorganized F-actin cytoskeleton, altered organization of focal adhesion proteins, and a weakly adherent phenotype. Based on our results, we propose that HT-1080s migrate in synthetic ECM with functional properties that are a direct consequence of their transformed phenotype.
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Affiliation(s)
- Michael P. Schwartz
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail: (MPS); (KSA)
| | - Robert E. Rogers
- College of Medicine, Texas A&M Health Science Center, Bryan, Texas, United States of America
| | - Samir P. Singh
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, Colorado, United States of America
| | - Justin Y. Lee
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, Colorado, United States of America
| | - Samuel G. Loveland
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Justin T. Koepsel
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Eric S. Witze
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, , United States of America
| | - Sara I. Montanez-Sauri
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Paul P. Carbone Comprehensive Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kyung E. Sung
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Paul P. Carbone Comprehensive Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Emi Y. Tokuda
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, Colorado, United States of America
| | - Yasha Sharma
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - Lydia M. Everhart
- Department of Chemical and Materials Engineering, University of Dayton, Dayton, Ohio, United States of America
| | - Eric H. Nguyen
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Muhammad H. Zaman
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - David J. Beebe
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Paul P. Carbone Comprehensive Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Natalie G. Ahn
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, Colorado, United States of America
- Howard Hughes Medical Institute, University of Colorado at Boulder, Boulder, Colorado, United States of America
| | - William L. Murphy
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Orthopedics and Rehabilitation, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kristi S. Anseth
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, Colorado, United States of America
- Howard Hughes Medical Institute, University of Colorado at Boulder, Boulder, Colorado, United States of America
- * E-mail: (MPS); (KSA)
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Sista S, Wen C, Hodgson PD, Pande G. The influence of surface energy of titanium-zirconium alloy on osteoblast cell functions in vitro. J Biomed Mater Res A 2011; 97:27-36. [PMID: 21308982 DOI: 10.1002/jbm.a.33013] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 10/18/2010] [Accepted: 11/18/2010] [Indexed: 11/07/2022]
Abstract
The success of an implant used for bone regeneration and repair is determined by the events that take place at the cell-material interface. An understanding of these interactions in vitro gives insights into the formulation of ideal conditions for their effective functioning in vivo. Thus, it is not only important to understand the physico-chemical properties of the materials but, also necessary to assess the cellular responses to them to determine their long-term stability and efficacy as implants. In the present study, we have compared the physico-chemical and biological properties of titanium (Ti) and two Ti-based alloys, namely: Ti- Zirconium (TiZr) and Ti-Niobium (TiNb). The morphology, chemical analysis, surface roughness, and contact angle measurements of the alloys were assessed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), profilometer, and contact angle goniometer, respectively whereas the biological properties of the materials were evaluated by measuring the adhesion, proliferation, and differentiation of MC3T3-E1 osteoblast cells on the surfaces of these alloys. Our results indicate that the biological properties of osteoblasts were better on TiZr surface than on TiNb surface. Furthermore, the surface energy and substrate composition influenced the superior biological activity of the TiZr alloy.
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Affiliation(s)
- Subhash Sista
- Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India; Institute for Technology Research and Innovation, Deakin University, Pigdons Road, Waurn Ponds, Geelong, Victoria 3217, Australia
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Fender P, Schoehn G, Perron-Sierra F, Tucker GC, Lortat-Jacob H. Adenovirus dodecahedron cell attachment and entry are mediated by heparan sulfate and integrins and vary along the cell cycle. Virology 2007; 371:155-64. [PMID: 17950396 DOI: 10.1016/j.virol.2007.09.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2007] [Revised: 08/22/2007] [Accepted: 09/07/2007] [Indexed: 11/30/2022]
Abstract
The adenovirus penton base is a strategic protein involved in the virus internalisation pathway through interaction between its RGD sequences and integrin. In some human adenovirus serotypes, this pentameric protein features the ability of interacting together by twelve, leading to the formation of a symmetric nanoparticle called dodecahedron (Dd). This non-infectious adenovirus-like particle exhibiting sixty RGD sequences interacts with integrin but also with heparan sulfate proteoglycans (HSPGs) expressed at the cell surface. In this study, we discriminate the respective importance of HSPGs and integrin on human adenovirus serotype 3 dodecahedron attachment and entry. Using different cell lines and a specific integrin inhibitor, we have determined that HSPGs are mainly responsible for particle attachment to the cell surface, favouring a strictly required interaction with integrin that triggers internalisation. No other receptors are involved in Dd entry and integrins on their own can mediate the particle entry in HSPGs-deficient cells. Moreover, integrin recognition by Dd is highly susceptible to cations and particularly to manganese that enhances particle binding by 4- to 7-fold compared to calcium. Interestingly, investigations on Dd receptors along the cell cycle revealed an enhanced particle targeting to mitotic cells and a loss of internalisation at this stage. This phenomenon observed with both HeLa- and HSPGs-deficient cells, depends on integrin remodelling during mitosis. This provides new clues for the use of this adenovirus nanoparticle as a delivery vector and sheds light on the integrin and HSPGs relationship in both resting and dividing cells.
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Affiliation(s)
- Pascal Fender
- CNRS, CEA, UJF: Institut de Biologie Structurale, 41 rue Jules Horowitz 38027 Grenoble, France.
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Goligorsky MS, Li H, Brodsky S, Chen J. Relationships between caveolae and eNOS: everything in proximity and the proximity of everything. Am J Physiol Renal Physiol 2002; 283:F1-10. [PMID: 12060581 DOI: 10.1152/ajprenal.00377.2001] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Caveolae, flask-shaped invaginations of the plasma membrane occupying up to 30% of cell surface in capillaries, represent a predominant location of endothelial nitric oxide synthase (eNOS) in endothelial cells. The caveolar coat protein caveolin forms high-molecular-weight, Triton-insoluble complexes through oligomerization mediated by interactions between NH2-terminal residues 61-101. eNOS is targeted to caveolae by cotranslational N-myristoylation and posttranslational palmitoylation. Caveolin-1 coimmunoprecipitates with eNOS; interaction with eNOS occurs via the caveolin-1 scaffolding domain and appears to result in the inhibition of NOS activity. The inhibitory conformation of eNOS is reversed by the addition of excess Ca2+/calmodulin and by Akt-induced phosphorylation of eNOS. Here, we shall dissect the system using the classic paradigm of a reflex loop: 1) the action of afferent elements, such as fluid shear stress and its putative caveolar sensor, on caveolae; 2) the ways in which afferent signals may affect the central element, the activation of the eNOS-nitric oxide system; and 3) several resultant well-established and novel physiologically important effector mechanisms, i.e., vasorelaxation, angiogenesis, membrane fluidity, endothelial permeability, deterrance of inflammatory cells, and prevention of platelet aggregation.
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Affiliation(s)
- Michael S Goligorsky
- Department of Medicine, State University of New York at Stony Brook, Stony Brook, New York 11794-8152, USA.
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Seidman MA, Hogan SM, Wendland RL, Worgall S, Crystal RG, Leopold PL. Variation in adenovirus receptor expression and adenovirus vector-mediated transgene expression at defined stages of the cell cycle. Mol Ther 2001; 4:13-21. [PMID: 11472101 DOI: 10.1006/mthe.2001.0414] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Detailed investigations have addressed the infection pathway of recombinant adenovirus (Ad) gene transfer vectors, but little attention has been paid to the influence of cell physiology on the outcome of Ad infection. Based on observations that Ad infection of clonal cell populations show cell-to-cell variability in the extent of capsid binding, we hypothesized that the cell cycle may influence the outcome of Ad infection. To address this hypothesis, we evaluated Ad association with cells in both unsynchronized and pharmacologically synchronized cell populations. In unsynchronized cell populations, elevated Ad association with cells correlated with expression of cyclin B1, a marker of entry into the M phase of mitosis. The same analysis conducted on cell populations that were synchronized at M phase (using paclitaxel or nocodazole) or at S phase (using aphidicolin) confirmed that M phase cells bound three- to sixfold more capsid compared with unsynchronized cells, which are primarily in the G(1) and G(2) phases. The elevated association of vectors with cells translated into 2.5- to 4-fold greater transgene expression 24 hours after infection. Assessment of cell surface expression of Ad receptors demonstrated that both the high-affinity coxsackie-adenovirus receptor for Ad fiber protein and the low-affinity alpha(v) integrin receptor for Ad penton base protein showed increased cell surface expression at M phase (1.5-fold and 2- to 3-fold increases, respectively). These data demonstrate that Ad infection of a homogenous population of cells can vary depending on the cell cycle stage, with enhanced Ad binding and expression correlating with the enhanced expression of Ad receptors during M phase. These observations have relevance to understanding the mechanisms of gene transfer by Ad vectors and should help in the design of in vivo gene transfer strategies.
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Affiliation(s)
- M A Seidman
- Division of Pulmonary and Critical Care Medicine, Weill Medical College of Cornell University, New York, NY, USA.
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Gopalakrishna P, Chaubey S, Manogaran P, Pande G. Modulation of ?5?1 integrin functions by the phospholipid and cholesterol contents of cell membranes. J Cell Biochem 2000. [DOI: 10.1002/(sici)1097-4644(20000615)77:4<517::aid-jcb1>3.0.co;2-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Deitch JS, Williams JK, Adams MR, Fly CA, Herrington DM, Jordan RE, Nakada MT, Jakubowski JA, Geary RL. Effects of beta3-integrin blockade (c7E3) on the response to angioplasty and intra-arterial stenting in atherosclerotic nonhuman primates. Arterioscler Thromb Vasc Biol 1998; 18:1730-7. [PMID: 9812911 DOI: 10.1161/01.atv.18.11.1730] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Because the beta3-antagonist abciximab (c7E3 Fab) has significantly improved late outcomes after coronary angioplasty, the beta3 integrins have been implicated in the arterial response to injury. However, the mechanisms underlying this benefit are unknown. The observation that c7E3 binds beta3 integrins on vascular cells (alphavbeta3) with affinity equal to that for the platelet glycoprotein IIb/IIIa integrin has led to the hypothesis that c7E3 may act directly on the artery wall to prevent restenosis after angioplasty. To test this hypothesis, we studied the effects of c7E3 on structural changes within the artery wall after angioplasty or stent angioplasty in 23 male cynomolgus monkeys with established atherosclerosis. Animals were randomly assigned to receive either a bolus of c7E3 (0.4 mg/kg IV, n=11) followed by a 48-hour infusion (0. 2 microg. kg-1. min-1) or an equal volume of vehicle (n=12). Animals received weight-adjusted aspirin and heparin and then underwent unilateral iliac artery experimental angioplasty and subclavian artery stent angioplasty (Palmaz). Iliac artery lumen diameter (LD) was determined by angiography at baseline (LDPre), after angioplasty (LDPost), and 35 days later (LDDay35). Arteries were then fixed by perfusion and removed for analysis. Lumen, intima, media, and external elastic lamina (EEL) areas were measured in iliac artery cross sections. Values from each injured iliac artery were normalized to the contralateral uninjured iliac artery to control for interanimal variability in baseline artery size and atherosclerosis extent. Intimal area was also measured in subclavian stent cross sections. c7E3 blocked platelet aggregation and prolonged the bleeding time from 2.8+/-1.1 to 19.8+/-2.5 minutes, P<0.001. Experimental angioplasty increased LDPost an average of 28%, and the initial gain was similar in both groups (P=NS). Despite an anti-platelet effect, c7E3 did not inhibit iliac lumen narrowing (LDDay35-LDPost: c7E3, -0.69+/-0.17 versus vehicle, -0.99+/-.17 mm, P=0.35); intimal hyperplasia (neointima area: c7E3, 1.12+/-.28 versus vehicle, 1.22+/-.20 mm2, P=0.77); or decrease in artery wall size (EEL area [percent of uninjured control]: c7E3, 101+/-7% versus vehicle, 121+/-7%). Stent intimal hyperplasia was also unaltered by c7E3 treatment (neointimal area: c7E3, 1.09+/-0.16 versus vehicle, 1. 28+/-0.11 mm2, P=0.36). These results suggest that the benefits of c7E3 treatment in coronary angioplasty were not from inhibition of intimal hyperplasia or improved artery wall remodeling. Alternative mechanisms should be explored to explain improved late outcomes after angioplasty in patients treated with c7E3.
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Affiliation(s)
- J S Deitch
- Departments of Surgery and Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
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Bauer A, Lickert H, Kemler R, Stappert J. Modification of the E-cadherin-catenin complex in mitotic Madin-Darby canine kidney epithelial cells. J Biol Chem 1998; 273:28314-21. [PMID: 9774455 DOI: 10.1074/jbc.273.43.28314] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
One of the hallmarks of polarized epithelial cells undergoing mitosis is their rounded morphology. This phenotype correlates with a reduced cell-substratum adhesion, apparently caused by a modulation of integrin function. However, it is still unclear whether the cadherin-mediated cell-cell adhesion is affected as well. To address this question, the cadherin complex was analyzed in different cell cycle stages of Madin-Darby canine kidney cells. By immunofluorescence, mitotic Madin-Darby canine kidney cells showed an increased staining of E-cadherin and the catenins (alpha-catenin, beta-catenin, plakoglobin, p120(ctn)) in the cytosol, suggesting a reorganization of the cadherin-catenin complex during mitosis. Biochemical analysis revealed that the overall amount of these components, as well as the proportion of the complex associated with the actin cytoskeleton, remained unchanged in mitotic cells. However, we found evidence for an internalization of E-cadherin during mitosis. In addition, the cadherin-catenin complex was analyzed for mitosis-specific changes in phosphorylation. We report a decrease in the tyrosine phosphorylation of beta-catenin, plakoglobin, and p120(ctn) during mitosis. Moreover, we observed a mitosis-specific Ser/Thr-phosphorylation of p120(ctn), as detected by the MPM-2 antibody. Hence, the cadherin/catenin complex is a target for different posttranslational modifications during mitosis, which may also have a profound impact on cadherin-mediated cell-cell adhesion.
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Affiliation(s)
- A Bauer
- Department of Molecular Embryology, Max-Planck Institute of Immunobiology, Stübeweg 51, D-79108 Freiburg, Germany
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