Description:
<jats:sec><jats:label /><jats:p>Protocadherin LKC (PLKC) is a member of the heterogeneous subgroup of protocadherins, which was identified and described as a potential tumor‐suppressor gene involved in contact inhibition. Several aspects of the structure, posttranslational processing, targeting and function of this new protocadherin are still not known. Here, we generated MDCK cell lines that stably express PLKC and investigated its cellular distribution, biosynthesis, glycosylation and association with detergent‐resistant membranes, particularly during cellular differentiation. We demonstrate that PLKC is localized at the apical membrane and adherens junctions, but it does not colocalize with the tight junctions proteins ZO‐1 and occludin. Unlike E‐cadherin, PLKC is not redistributed from the cell membrane to submembranous and vesicular structures upon Ca<jats:sup>2+</jats:sup> removal. Interestingly, PLKC associates during differentiation with detergent‐resistant membranes that trigger its redistribution from intracellular membranes to the cell surface. This association occurs concomitant with alterations in the O‐glycosylation pattern that is increased in postconfluent, i.e. well differentiated MDCK cells. Finally, we demonstrate that PLKC is directly involved in the establishment of a proper epithelial cell polarity.</jats:p><jats:p><jats:italic>This work has been supported by grants from the German Research Council, DFG (SFB 621) to HYN.</jats:italic></jats:p></jats:sec>