Reduced E-cadherin–mediated cell adhesion by a constitutively monomeric E-cadherin/αE-catenin chimera. (A) Schematic representation of E-cadΔ70/β/α, in which residues 118–151 of β-catenin are inserted in between E-cadherin and αE-catenin. (B) SEC of E-cadΔ70/β/α (black line), E-cadΔ70/α dimer (green dotted line), and monomer (purple dotted line). (C) CBB-stained Native-PAGE of increasing concentrations of E-cadΔ70/β/α that were incubated for 16 h at 37°C. Quantification of the percent dimerization of E-cadΔ70/β/α compared with E-cadΔ70/α. n = 3. (D) Coimmunoprecipitation of Myc tagged with HA-tagged chimeras, using either E-cadΔ70/α or E-cadΔ70/β/α. Upon immunoprecipitation with HA antibodies, proteins were separated by SDS-PAGE and immunoblotted for HA and Myc. Quantification of the relative binding between differentially tagged E-cadΔ70/α and E-cadΔ70/β/α is shown. n = 4. (E) Immunofluorescence of E-cadΔ70/α and E-cadΔ70/β/α in L cells with an antibody to the extracellular domain of E-cadherin. (F) Adhesion to E-cadherin-Fc of L cells transfected with E-cadherin-GFP, E-cadΔ70/α, E-cadΔ70/β/α, or empty vector control, together with luciferase. Background adhesion to a no calcium control was subtracted, and the mean percentage of adherent cells relative to the total input luciferase signal and normalized to E-cadherin-GFP values is shown. n = 5 with standard deviation. An unpaired Student’s t test was performed for statistical analysis. (G) Hanging drop assay of L cells transfected with E-cadherin-GFP, E-cadΔ70/α, E-cadΔ70/β/α, or empty vector control showing the percentage of clusters of four or more cells, normalized to levels observed with E-cadherin. n = 3, with standard deviation. An unpaired Student’s t test was performed for statistical analysis.