Figure 4.

Redundant roles for p120 family members ARVCF and δ-catenin. A431 cells stably expressing human p120 siRNA were transiently transfected with ARVCF-GFP, δ-catenin–GFP, or myc-tagged plakophilin-3 (Pkp-3-myc). 24 h after transfection, cells were plated sparsely and individual colonies grew for 2 d. Levels of the transfected proteins and E-cadherin were then analyzed by immunofluorescence. GFP expression alone (i, eluminated cells) did not affect E-cadherin levels (ii). Both ARVCF-GFP (iii) and δ-catenin–GFP (v) substantially increased levels of E-cadherin (iv and vi) and rescued cell–cell adhesion. In contrast, plakophilin-3 (vii), a p120-related protein that does not bind classical cadherins, but had no effect on E-cadherin levels (viii) or cell–cell adhesion.