In:
Molecular Biology of the Cell, American Society for Cell Biology (ASCB), Vol. 11, No. 8 ( 2000-08), p. 2793-2802
Abstract:
The role of platelet endothelial cell adhesion molecule-1 (PECAM-1) in endothelial cell–cell interactions and its contribution to cadherin-mediated cell adhesion are poorly understood. Such studies have been difficult because all known endothelial cells express PECAM-1. We have used Madin-Darby canine kidney (MDCK) cells as a model system in which to evaluate the role of PECAM-1 isoforms that differ in their cytoplasmic domains in cell–cell interactions. MDCK cells lack endogenous PECAM-1 but form cell–cell junctions similar to those of endothelial cells, in which PECAM-1 is concentrated. MDCK cells were transfected with two isoforms of murine PECAM-1, Δ15 and Δ14 & 15, the predominant isoforms expressed in vivo. Expression of the Δ15 isoform resulted in apparent dedifferentiation of MDCK cells concomitant with the loss of adherens junctions, down-regulation of E-cadherin, α- and β-catenin expression, and sustained activation of extracellular regulated kinases. The Δ15 isoform was not concentrated at cell–cell contacts. In contrast, the Δ14 & 15 isoform localized to sites of cell–cell contact and had no effect on MDCK cell morphology, cadherin/catenin expression, or extracellular regulated kinase activity. Thus, the presence of exon 14 in the cytoplasmic domain of PECAM-1 has dramatic effects on the ability of cells to maintain adherens junctions and an epithelial phenotype. Therefore, changes in the expression of exon 14 containing PECAM-1 isoforms, which we have observed during development, may have profound functional consequences.
Type of Medium:
Online Resource
ISSN:
1059-1524
,
1939-4586
DOI:
10.1091/mbc.11.8.2793
Language:
English
Publisher:
American Society for Cell Biology (ASCB)
Publication Date:
2000
detail.hit.zdb_id:
1474922-1
SSG:
12
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