A dileucine motif targets E-cadherin to the basolateral cell surface in Madin-Darby canine kidney and LLC-PK1 epithelial cells Journal Article
| Authors: | Miranda, K. C.; Khromykh, T.; Christy, P.; Le, T. L.; Gottardi, C. J.; Yap, A. S.; Stow, J. L.; Teasdale, R. D. |
| Article Title: | A dileucine motif targets E-cadherin to the basolateral cell surface in Madin-Darby canine kidney and LLC-PK1 epithelial cells |
| Abstract: | E-cadherin is a major adherens junction protein of epithelial cells, with a central role in cell-cell adhesion and cell polarity. Newly synthesized E-cadherin is targeted to the basolateral cell surface. We analyzed targeting information in the cytoplasmic tail of E-cadherin by utilizing chimeras of E-cadherin fused to the ectodomain of the interleukin-2α (IL-2α) receptor expressed in Madin-Darby canine kidney and LLC-PK1 epithelial cells. Chimeras containing the full-length or membrane-proximal half of the E-cadherin cytoplasmic tail were correctly targeted to the basolateral domain. Sequence analysis of the membrane-proximal tail region revealed the presence of a highly conserved dileucine motif, which was analyzed as a putative targeting signal by mutagenesis. Elimination of this motif resulted in the loss of Tac/E-cadherin basolateral localization, pin-pointing this dileucine signal as being both necessary and sufficient for basolateral targeting of E-cadherin. Truncation mutants unable to bind β-catenin were correctly targeted, showing, contrary to current understanding, that β-catenin is not required for basolateral trafficking. Our results also provide evidence that dileucine-mediated targeting is maintained in LLC-PK 1 cells despite the altered polarity of basolateral proteins with tyrosine-based signals in this cell line. These results provide the first direct insights into how E-cadherin is targeted to the basolateral membrane. |
| Keywords: | unclassified drug; nonhuman; molecular genetics; polymerase chain reaction; protein motif; proteins; animal cell; animal; cytology; metabolism; animals; gene expression; basement membrane; cell line; immunofluorescence; tyrosine; uvomorulin; animalia; chemistry; amino acid sequence; molecular sequence data; sequence homology, amino acid; dog; dogs; nucleotide sequence; membrane protein; immunoprecipitation; immunoblotting; epithelium cell; epithelial cells; base sequence; cell polarity; amino acid; dna primers; primer dna; sequence homology; leucine; biochemistry; beta catenin; cadherin; cadherins; biological organs; swine; synthesis (chemical); complementary dna; amino acid motifs; biotinylation; plasmid dna; cells; canis familiaris; interleukin 2 receptor; cell strain; biological membranes; priority journal; article; interleukin 2alpha receptor; basolateral membrane; llc-pk1 cells |
| Journal Title: | Journal of Biological Chemistry |
| Volume: | 276 |
| Issue: | 25 |
| ISSN: | 0021-9258 |
| Publisher: | American Society for Biochemistry and Molecular Biology |
| Date Published: | 2001-06-22 |
| Start Page: | 22565 |
| End Page: | 22572 |
| Language: | English |
| DOI: | 10.1074/jbc.M101907200 |
| PUBMED: | 11312273 |
| PROVIDER: | scopus |
| DOI/URL: | |
| Notes: | Export Date: 21 May 2015 -- Source: Scopus |
