Figure 9.

Effect of PC overexpression on distribution of occludin, ZO-1, and pan-cadherin in MDCK cells. Localization of PC, occludin, ZO-1, and cadherin in parental MDCK cells (a, c, e, and g) and MDCK-PC8 cells stably overexpressing PC (b, d, f, and h). A honeycomb-like staining pattern is observed for both occludin (c) and ZO-1 (e) in parental cells when the focus is at the TJ level. In transfected MDCK cells, staining for both occludin (d) and ZO-1 (f) is more concentrated at the intersection (arrowheads) of cell–cell boundaries where three cells meet. In parental cells, staining for cadherin is uniform along the entire lateral membrane (g), whereas in transfected MDCK-PC8 cells (h), cadherin staining is less uniform and is more concentrated between the intersections (asterisks), rather than at the intersections (arrows), when the focus is at the level of the junctions. Cells were fixed in 2% paraformaldehyde and processed for double immunofluorescence as described in MATERIALS AND METHODS. Bars, 10 μm.