Fig. 4. Subcellular distribution of MAGI-3 in epithelial cells. Caco2 colon carcinoma cells were double labeled using a polyclonal antibody to MAGI-3 (A,D,G,J) and monoclonal antibodies to ß-catenin (B), desmoplakin (E), cingulin (H) or ZO-1 (K) as indicated. MAGI-3 is shown in red, all other proteins in green, and DAPI-labeled nuclei are blue. Merge images of each set are shown on the right. Higher magnification of the region labeled with an asterisk from the merge image is shown in the inset of each panel. Note that MAGI-3 colocalized with cingulin and ZO-1 but not with ß-catenin or desmoplakin. Similar cellular distribution of MAGI-3 in Caco2 cells was also detected using a distinct monoclonal antibody (M). The localization of MAGI-3 in transfected MDCK cells, which do not express endogenous MAGI-3, is presented in panels N, or as a double staining with Claudin-1 (O; green). Bars, A-L, 15 µm; M, 20 µm; N-O, 40 µm.