Cadherin-mediated specific cell adhesion and animal morphogenesis.

Cadherins are a family of transmembrane glycoproteins which are responsible for Ca2+-dependent cell-cell adhesion. Each member of the family displays a unique pattern of tissue distribution. The expression of cadherin molecules in an embryo is spatiotemporally regulated so as to be associated with a variety of morphogenetic events. Antibodies against cadherins perturb the morphogenesis of tissues, indicating their importance in tissue formation. When cells were transfected with cDNAs encoding cadherins, they expressed the exogenous cadherin molecules and these were functional. Using these transfected cells, we tested whether each member of the cadherin family has a binding specificity, and found that cells preferentially adhere to those expressing the identical cadherin type. The cadherin-mediated specific adhesion also occurred in the attachment of neurites to the surface of other cells. These observations suggest that cadherins are crucial for the selective adhesiveness of cells, and thus for the embryonic morphogenetic processes in which specific adhesive interactions of cells are involved.