Fig 1: Extra-desmosomal plakophilin-3 clusters are recruited to cell–cell junction-associated actin bundles. Triple-fluorescence microscopy of A431 cells stained for actin filaments (act, green), plakophilin-3 (Pkp3, red), and the desmosomal cadherin, desmoglein-2 (Dsg2, blue). The upper micrographs show a low magnification of a group of cells. Scale bar, 25 µm. Zoomed images of four representative cell-cell contact regions that are designated with dashed boxes (numbered 1 to 4) are in the bottom rows. Note that desmoglein-2 and plakophilin-3 are colocalized in desmosomes. In addition to desmosomes, each of the selected regions contains several plakophilin-3-positive clusters of different sizes (some of them are indicated with arrows), which are desmoglein-2-deficient but align along the actin-enriched structures. One of them (marked by the arrowhead in the region #1) is shown zoomed-in in the insets. Note that this large plakophilin-3 cluster incorporates several small desmosomes. Bars, 7 µm.