title: Endogenous N-cadherin in a subpopulation of MDCK cells: distribution and catenin complex composition.
abstract: Epithelial (E)-cadherin plays a critical role in developing a normal epithelial phenotype but neural (N)-cadherin can disrupt epithelial shape, at least in carcinoma-derived cells. Here the normal epithelial cell line MDCK was used to select for a trypsin-sensitive (TS-MDCK) subpopulation that expresses low levels of endogenous N-cadherin. Similar amounts of E-cadherin and all catenins are found in both TS-MDCK and trypsin-resistant cells (TR-MDCK), but TS-MDCK are less phenotypically epithelioid and more motile, and junctional proteins are more detergent soluble. In TS-MDCK, N-cadherin is largely nonjunctional; a similar N-cadherin distribution and mesenchymal phenotype are found in TR-MDCK transfected to express low levels of exogenous N-cadherin. Little N-cadherin was attracted to junctions between TS-MDCK and hTERT-RPE1 cells, a retinal pigment epithelium-derived line that expresses dominantly N-cadherin. No differences were seen in E-cadherin-catenin complexes in TS- and TR-MDCK, but N-cadherin-catenin complexes in TS-MDCK have more abundant p120 catenin. Overall, the results indicate that E- and N-cadherin assemble stoichiometrically different complexes with p120 in the same cells. Further, N-cadherin does not participate with E-cadherin in a zonular epithelial junction in normal MDCK epithelial cells. Rather, even low levels of endogenous N-cadherin contribute to a disrupted epithelial phenotype, resembling the effect of N-cadherin on carcinoma-derived epithelial cells.
authors.affiliation: Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, WI 53226-4812, USA.
authors.forename: Yong-Ha
authors.initials: YH
authors.lastname: Youn
authors.forename: Jeehee
authors.initials: J
authors.lastname: Hong
authors.forename: Janice M
authors.initials: JM
authors.lastname: Burke
mesh_terms: D000818:Animals; D001483:Base Sequence; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D051177:Catenins; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002460:Cell Line; D018076:DNA, Complementary / Q000235:genetics; D004285:Dogs; D015870:Gene Expression; D006801:Humans; D046912:Multiprotein Complexes; D010641:Phenotype; D010750:Phosphoproteins / Q000378:metabolism*; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012995:Solubility; D014162:Transfection; D000095002:Delta Catenin
chemical_list: D015820:Cadherins; D051177:Catenins; D015815:Cell Adhesion Molecules; D018076:DNA, Complementary; D046912:Multiprotein Complexes; D010750:Phosphoproteins; D011994:Recombinant Proteins; D000095002:Delta Catenin