ASSOCIATION OF THE APC GENE-PRODUCT WITH BETA-CATENIN

Mutations in the human APC gene are linked to familial adenomatous pol yposis and to the progression of sporadic colorectal and gastric tumor s. To gain insight into APC function, APC-associated proteins were ide ntified by immunoprecipitation experiments. Antibodies to APC precipit ated a 95-kilodalton protein that was purified and identified by seque ncing as beta-catenin, a protein that binds to the cell adhesion molec ule E-cadherin. An antibody specific to beta-catenin also recognized t he 95-kilodalton protein in the immunoprecipitates. These results sugg est that APC is involved in cell adhesion.