Figure 6.

PS1 promotes cytoskeletal association of the cadherin/catenin complexes. (A) Confluent cultures of E-cadherin-transfected PS1+/+ or PS1−/− fibroblasts were extracted in 1% Triton X-100, and insoluble fractions were solubilized in urea buffer (see Materials and Methods). Sixty micrograms of protein of the Triton X-100-soluble fraction or 75 μg of the insoluble fraction was then probed with antibodies against γ-catenin (γ-cat) or E-cadherin (E-cad). (B) Extracts from E-cadherin-transfected PS1−/− fibroblasts, transiently transfected with vector (VECT), WT PS1 (wtPS1), or PS1 FAD mutant ΔE9 (PS1ΔE9), were prepared and probed as in A, plus anti-β-catenin (β-cat) antibodies.