cDNAs of cell adhesion molecules of different specificity induce changes in cell shape and border formation in cultured S180 cells.

Abstract

Abstract. The liver cell adhesion molecule (L-CAM) and N-cadherin or adherens junction-specific CAM (A-CAM) are structurally related cell surface glycoproteins that mediate calcium-dependent adhesion in different tissues. We have isolated and characterized a full-length cDNA clone for chicken N-cadherin and used this clone to transfect S180 mouse sarcoma cells that do not normally express N-cadherin. The transfected cells (S180cadN cells) expressed N-cadherin on their surfaces and resembled S180 cells transfected with L-CAM (S180L cells) in that at confluence they formed an epithelioid sheet and displayed a large increase in the number of adherens and gap junctions. In addition, N-cadherin in S180cadN cells, like L-CAM in S180L ceils, accumulated at cellular boundaries where it was colocalized with cortical actin. In S180L ceils and S180cadN cells, L-CAM and N-cadherin were seen at sites of adherens junctions but were not restricted to these areas. Adhesion mediated by either CAM was inhibited by treatment with cytochalasin D that disrupted the actin network of the transfected cells. Despite their known structural similarities, there was no evidence of interaction between L-CAM and N-cadherin.Doubly transfected cells (S180L/cadN) also formed epithelioid sheets. In these cells, both N-cadherin and L-CAM colocalized at areas of cell contact and the presence of antibodies to both CAMs was required to disrupt the sheets of cells. Studies using divalent antibodies to localize each CAM at the cell surface or to perturb their distributions indicated that in the same cell there were no interactions between L-CAM and N-cadherin molecules.These data suggest that the Ca++-dependent CAMs are likely to play a critical role in the maintenance of epithelial structures and support a model for the segregation of epithelia based on differences in specificity of CAM mediated binding. They also provide further support for the so-called precedence hypothesis that proposes that expression and homophilic binding of CAMs are necessary for formation of junctional structures in epithelia.

N‐cadherin transcripts in Xenopus laevis from early tailbud to tadpole

“…A series of elegant experiments have shown that fibroblastic cells transfected with cadherins acquire an epitheloid morphology Nagafuchi et al, 1987;Friedlander et al, 1989;Miyatani et al, 1989). Mixed aggregates of transfected cells expressing different levels of cadherin or distinct cadherins will sort out, emphasizing the importance of cadherins in the function of tissue boundaries and positioning of cells within tissues (Matsuzaki et al, 1990;Mege et al, 1988;Nose et al, 1988).…”

Lamellipodium extension and cadherin adhesion: two cell responses to cadherin activation relying on distinct signalling pathways

“…The mouse myogenic C2 cell line (Yaffe and Saxel, 1977) and the chicken N-cadherin-expressing S180 cell line, N-cad S180 (Matsuzaki et al, 1990), were grown in Dulbecco's modified Eagle's medium (DMEM) plus Glutamax supplemented with 10% fetal calf serum under 7.5% CO2 at 37°C. The human adenocarcinoma SW48 epithelial cell line (from ATCC) was grown in Leibovitz's medium (L-15) plus L-Glutamine 2.0 mM and 10% fetal calf serum in the absence of CO2 at 37°C.…”

In the First Extracellular Domain of E-cadherin, Heterophilic Interactions, but Not the Conserved His-Ala-Val Motif, Are Required for Adhesion

“…Both the extracellular and the intracellular portions of the cadherin play critical roles in mediating adhesion (6). Perturbation and expression experiments have demonstrated that cadherin-mediated adhesion promotes a range of cellular processes subsequent to adhesion, including epithelial polarization (7,8), blastula compaction (2), neurite outgrowth (9,10), and formation of desmosomes (11,12) and gap junctions (13)(14)(15)(16).…”