Interaction of the DF3/MUC1 breast carcinoma-associated antigen and β- catenin in cell adhesion

Abstract

The DF3/MUC1 mucin-like glycoprotein is aberrantly overexpressed in human breast carcinomas. The functional role of DF3 is unknown. The present studies demonstrate that DF3 associates with β-catenin. Similar findings have been obtained for γ-catenin but not α-catenin. DF3, like E-cadherin and the adenomatous polyposis coli gene product, contains an SXXXXXSSL site that is responsible for direct binding to β-catenin. The results further demonstrate that interaction of DF3 and β-catenin is dependent on cell adhesion. These findings and the role of β-catenin in cell signaling support a role for DF3 in the adhesion of epithelial cells.