scholarly journals Evidence for regulated dimerization of cell-cell adhesion molecule (C-CAM) in epithelial cells

1996 ◽  
Vol 320 (3) ◽  
pp. 847-853 ◽  
Author(s):  
Irene HUNTER ◽  
Hiroki SAWA ◽  
Magnus EDLUND ◽  
Björn ÖBRINK
Keyword(s):  
Cell Adhesion ◽  
Epithelial Cells ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
Plasma Membranes ◽  
Immunoglobulin Superfamily ◽  
Dimer Formation ◽  
Rat Liver Plasma Membranes ◽  
Self Association ◽  
Covalently Linked

C-CAM is a Ca2+-independent cell adhesion molecule (CAM) belonging to the immunoglobulin superfamily. Addition of chemical cross-linkers to isolated rat liver plasma membranes, intact epithelial cells and purified preparations of C-CAM stabilized one major C-CAM-containing product whose apparent molecular mass was approximately twice that of the C-CAM monomer. The failure to detect additional proteins after cleavage of the cross-linked species demonstrated that C-CAM exists as non-covalently linked dimers both in solution and on the cell surface. Dimerization occurred to the same extent in adherent monolayers and in single cell populations, indicating that dimer formation was the result of cis- interactions within the membranes of individual cells. Using isoform-specific anti-peptide antibodies, both C-CAM1 and C-CAM2 were found to be involved in dimerization, forming predominantly homo-dimeric species. Both calmodulin and Ca2+ ionophore modulated the level of dimer formation, suggesting a role for regulated self-association in the functional activity of C-CAM.

scholarly journals Human Blastocysts and Endometrial Epithelial Cells Express Activated Leukocyte Cell Adhesion Molecule (ALCAM/CD166)

2003 ◽  
Vol 88 (7) ◽  
pp. 3437-3443 ◽  
Author(s):  
Hiroshi Fujiwara ◽  
Keiji Tatsumi ◽  
Kenzo Kosaka ◽  
Yukiyasu Sato ◽  
Toshihiro Higuchi ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Epithelial Cells ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
Endometrial Epithelial Cells

scholarly journals Vascular Cell Adhesion Molecule-1 Is Expressed by Cortical Thymic Epithelial Cells and Mediates Thymocyte Adhesion. Implications for the Function of α4β1 (VLA4) Integrin in T-Cell Development

Blood ◽  
1997 ◽  
Vol 89 (7) ◽  
pp. 2461-2471 ◽  
Author(s):  
Daniel R. Salomon ◽  
Laura Crisa ◽  
Christopher F. Mojcik ◽  
Jennifer K. Ishii ◽  
George Klier ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
T Cell ◽  
Epithelial Cells ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
T Cell Development ◽  
Vascular Cell Adhesion ◽  
Vascular Cell ◽  
Vascular Cell Adhesion Molecule ◽  
Cell Adhesion Molecule 1

Abstract T-cell development requires a series of discrete selection and activation signals delivered to maturing progenitors in the thymic cortex and medulla. We have previously shown the constitutive activity of the integrin, α4β1 (VLA4), on a unique subpopulation of immature cortical thymocytes and proposed a role for integrin-mediated adhesion in positive selection by cortical epithelium. In the present report we show that thymic epithelial cell lines express vascular cell adhesion molecule-1 (VCAM-1) a high-affinity ligand for α4β1, and that VCAM-1 mediates thymocyte binding to these lines. Immunohistochemistry and confocal microscopy show that VCAM-1 is selectively expressed in situ by thymic epithelium in the cortex and corticomedullary junction, two locations at which VCAM-1 could determine the interaction between immature thymocytes and selecting elements on epithelial cells. In parallel, we confirmed that fibronectin (FN), the alternative ligand for α4β1, is expressed predominantly in the medulla. These results suggest that VCAM-1 is an adhesive ligand in the thymic cortex for the activated form of α4β1 constitutively expressed during development by immature double positive thymocytes. The structural segregation of the alternative ligand, FN, to the medulla suggests that medullary FN may regulate the migration, development, and export of more mature thymocytes.

scholarly journals Cell-adhesion molecule uvomorulin is localized in the intermediate junctions of adult intestinal epithelial cells.

1985 ◽  
Vol 100 (1) ◽  
pp. 327-332 ◽  
Author(s):  
K Boller ◽  
D Vestweber ◽  
R Kemler
Keyword(s):  
Cell Adhesion ◽  
Epithelial Cells ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
Intestinal Epithelial Cells ◽  
Rabbit Antiserum ◽  
Preimplantation Embryos ◽  
Intestinal Epithelial ◽  
Electron Microscopic ◽  
A Cell

Uvomorulin is a cell-adhesion molecule implicated in the compaction process of mouse preimplantation embryos and the aggregation of embryonal carcinoma cells. A rabbit antiserum against purified uvomorulin also reacts with epithelial cells of various adult tissues. In this study, we investigated the localization of uvomorulin on adult intestinal epithelial cells using electron microscopic analyses. Uvomorulin was shown to exhibit a highly restricted localization in the intermediate junctions of these cells. The results are discussed with respect to a possible adhesive function of uvomorulin on intestinal epithelial cells.

Axonal cell-adhesion molecule L1 in CNS myelination

2004 ◽  
Vol 1 (1) ◽  
pp. 65-72 ◽  
Author(s):  
G. BARBIN ◽  
M.S. AIGROT ◽  
P. CHARLES ◽  
A. FOUCHER ◽  
M. GRUMET ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
Culture Medium ◽  
Immunoglobulin Superfamily ◽  
Map Kinase Pathway ◽  
Cell Adhesion Molecule L1 ◽  
Cns Myelination ◽  
Kinase Pathway

Of the axonal signals influencing myelination, adhesion molecules expressed at the axonal surface are strong candidates to mediate interactions between myelinating cells and axons. The recognition cell-adhesion molecule L1, a member of the immunoglobulin superfamily has been shown to play important roles in neuronal migration and survival, and in PNS myelination. We have investigated the role of axonally expressed L1 in CNS myelination. In co-cultures of myelinating oligodendrocytes and neurons derived from murine brain, we demonstrate that, before myelination, L1 immunoreactivity is confined to neurites. After myelination commences, L1 expression is downregulated on myelinated axons and adjacent, but not yet myelinated, internodes. Interfering with L1 before the onset of myelination, by adding either anti-L1 antibody or L1-Fc fusion proteins to the culture medium, inhibits myelination. In addition, in purified cultures of oligodendrocytes, L1-Fc fusion protein prevents lysophosphatidic acid-induced activation of the mitogen-activated kinase (MAP)-kinase pathway. Together, our data indicate that L1 is involved in the initiation of CNS myelination, and that this effect might involve the dephosphorylation of oligodendroglial phosphoproteins.

scholarly journals Direct and Regulated Interaction of Integrin αEβ7 with E-Cadherin

1998 ◽  
Vol 140 (1) ◽  
pp. 197-210 ◽  
Author(s):  
Jonathan M.G. Higgins ◽  
Didier A. Mandlebrot ◽  
Sunil K. Shaw ◽  
Gary J. Russell ◽  
Elizabeth A. Murphy ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Fusion Protein ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
Divalent Cations ◽  
Cell Receptor ◽  
Intraepithelial Lymphocytes ◽  
Vital Role ◽  
Immunoglobulin Superfamily ◽  
E Cadherin

The cadherins are a family of homophilic adhesion molecules that play a vital role in the formation of cellular junctions and in tissue morphogenesis. Members of the integrin family are also involved in cell to cell adhesion, but bind heterophilically to immunoglobulin superfamily molecules such as intracellular adhesion molecule (ICAM)–1, vascular cell adhesion molecule (VCAM)–1, or mucosal addressin cell adhesion molecule (MadCAM)–1. Recently, an interaction between epithelial (E-) cadherin and the mucosal lymphocyte integrin, αEβ7, has been proposed. Here, we demonstrate that a human E-cadherin–Fc fusion protein binds directly to soluble recombinant αEβ7, and to αEβ7 solubilized from intraepithelial T lymphocytes. Furthermore, intraepithelial lymphocytes or transfected JY′ cells expressing the αEβ7 integrin adhere strongly to purified E-cadherin–Fc coated on plastic, and the adhesion can be inhibited by antibodies to αEβ7 or E-cadherin. The binding of αEβ7 integrin to cadherins is selective since cell adhesion to P-cadherin–Fc through αEβ7 requires >100-fold more fusion protein than to E-cadherin–Fc. Although the structure of the αE-chain is unique among integrins, the avidity of αEβ7 for E-cadherin can be regulated by divalent cations or phorbol myristate acetate. Cross-linking of the T cell receptor complex on intraepithelial lymphocytes increases the avidity of αEβ7 for E-cadherin, and may provide a mechanism for the adherence and activation of lymphocytes within the epithelium in the presence of specific foreign antigen. Thus, despite its dissimilarity to known integrin ligands, the specific molecular interaction demonstrated here indicates that E-cadherin is a direct counter receptor for the αEβ7 integrin.

scholarly journals Junctional adhesion molecule (JAM) binds to PAR-3

2001 ◽  
Vol 154 (3) ◽  
pp. 491-498 ◽  
Author(s):  
Masahiko Itoh ◽  
Hiroyuki Sasaki ◽  
Mikio Furuse ◽  
Harunobu Ozaki ◽  
Toru Kita ◽  
...  
Keyword(s):  
Adhesion Molecule ◽  
Plasma Membranes ◽  
Molecular Mechanisms ◽  
Spatial Relationship ◽  
Immunoglobulin Superfamily ◽  
Binding Assays ◽  
Adhesion Sites ◽  
Vitro Binding ◽  
Self Association

At tight junctions (TJs), claudins with four transmembrane domains are incorporated into TJ strands. Junctional adhesion molecule (JAM), which belongs to the immunoglobulin superfamily, is also localized at TJs, but it remains unclear how JAM is integrated into TJs. Immunoreplica electron microscopy revealed that JAM showed an intimate spatial relationship with TJ strands in epithelial cells. In L fibroblasts expressing exogenous JAM, JAM was concentrated at cell–cell adhesion sites, where there were no strand-like structures, but rather characteristic membrane domains free of intramembranous particles were detected. These domains were specifically labeled with anti-JAM polyclonal antibody, suggesting that JAM forms planar aggregates through their lateral self-association. Immunofluorescence microscopy and in vitro binding assays revealed that ZO-1 directly binds to the COOH termini of claudins and JAM at its PDZ1 and PDZ3 domains, respectively. Furthermore, another PDZ-containing polarity-related protein, PAR-3, was directly bound to the COOH terminus of JAM, but not to that of claudins. These findings led to a molecular architectural model for TJs: small aggregates of JAM are tethered to claudin-based strands through ZO-1, and these JAM aggregates recruit PAR-3 to TJs. We also discuss the importance of this model from the perspective of the general molecular mechanisms behind the recruitment of PAR proteins to plasma membranes.

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