Fig. 5. Effect of cell permeable Antennapedia fusion peptides that mimic the p120ctn binding site on N-cadherin on the composition and function of the cadherin complex of proteins in E9 chick retina cells. (A) Intact E9 retina cells were incubated in the presence of the indicated peptide for 60 minutes or 120 minutes at room temperature. The cells were homogenized in buffer containing 1% NP-40 and immunoprecipitated with NCD-2. The resulting immuno-complexes were analyzed by western blot with the indicated antibody. (B) Intact E9 retina cells were incubated in the presence of the indicated peptide for 60 minutes at room temperature lysed in RIPA buffer, immunoprecipitated with anti-ß-catenin antibody and analysed by western blot using anti-phosphotyrosine antibody. The blots were then stripped and blotted with anti-ß-catenin antibody. (C) Retina cells were incubated with the indicated peptides and labeled with a cell-impermeable biotinylation reagent. The cells were lysed as above, cell-surface N-cadherin `pulled down' with avidin-coated beads, fractionated by SDS-PAGE and visualized by western blot with anti-N-cadherin antibody. An aliquot of the total lysate was also analyzed by western blot, for comparison. (D) Dissociated E8 chick neural retina cells were incubated for 1 hour at room temperature in the presence of the indicated peptide. Adhesion to immobilized Fc-N-cad is expressed as the percentage of adhesion in the absence of added peptide.