Polymorphism of AJs in α-catenin–expressing 468 cells. (a) Immunofluorescence staining of the parental α-catenin–deficient 468 cells for E-cadherin (Ec) and actin filaments (Act). The boxed regions are magnified on the right. Note that E-cadherin molecules can assemble only into tiny clusters. (b) Dn-αCat–expressing 468 cells triple stained for Dendra2 (Dn), actin (Act), and vinculin (Vin). The arrows and the asterisk point to the basolateral and apicolateral junctions, respectively, which are positive for all three markers. The α-catenin–negative focal contacts are indicated by arrowheads. (c) Dn-αCat–expressing 468 cells triple stained for Dendra2 (Dn), actin (Act), and a TJ protein cingulin (Cin). Apical (left) and basal (right) focus planes are shown. Note that the apicolateral AJs associate with TJs and with a fine actin staining (apical focus plane). The lateral cell membranes are enriched with numerous lateral spot-like junctions, which did not show clear association with actin structures. The base of the lateral membranes formed basolateral AJs associated with the radial actin bundles (basal focus plane). Schematic representation of the Dn-αCat is given on the top of image. Dn denotes the GFP Dendra2. αH denotes the head domain of α-catenin implicated in binding to β-catenin and homodimerization. M1–M3 and αABD denote middle domains and αABD of α-catenin, respectively. Bars, 10 µm.