The cytoplasmic domain of CEACAM1-L controls its lateral localization and the organization of desmosomes in polarized epithelial cells
Author:
Sundberg Ulla1, Beauchemin Nicole2, Öbrink Björn1
Affiliation:
1. Department of Cell and Molecular Biology, Medical Nobel Institute, Karolinska Institute, 171 77 Stockholm, Sweden 2. McGill Cancer Center, McGill University, Montreal, QC H3G 1Y6, Canada
Abstract
Two CEACAM1 isoforms with different cytoplasmic domains, CEACAM1-L and CEACAM1-S, are unequally distributed in polarized epithelial MDCK cells. CEACAM1-S is exclusively apical whereas CEACAM1-L occurs both in apical and lateral cell surfaces. Using confocal microscopy and CEACAM1-L mutants, we identified several amino acids in the cytoplasmic domain that were instrumental for the lateral localization. Tyr515, but not Tyr488, constituted a prominent lateral targeting signal. Pervanadate-stimulated Tyr phosphorylation induced rapid phosphatidylinositol 3-kinase-dependent disappearance of lateral CEACAM1-L, whereas staurosporine, a Ser/Thr kinase inhibitor, resulted in slower phosphatidylinositol 3-kinase-independent disappearance. Both drugs caused accumulation of CEACAM1-L in a late endosome/lysosome compartment. Colocalization studies of occludin, ZO-1, E-cadherin, β-catenin and desmoplakin indicated that laterally localized CEACAM1-L was present in adherens junctions but not in tight junctions or desmosomes. Overexpressed CEACAM1-L did not affect the organization of tight junction or adherens junction proteins, but perturbed the arrangement of desmosomes. The abundance of desmosomes in the lateral cell surfaces decreased significantly and the submembraneous cytokeratin filaments became disorganized. The signal for desmosomal perturbance resided within amino acids 484-518 in the C-terminal part of the cytoplasmic domain, among which an intact Tyr515 was indispensable.
Publisher
The Company of Biologists
Reference50 articles.
1. Beauchemin, N., Draber, P., Dveksler, G., Gold, P., Gray-Owen, S., Grunert, F., Hammarström, S., Holmes, K. V., Karlsson, A., Kuroki, M. et al. (1999). Redefined nomenclature for members of the carcinoembryonic antigen family. Exp. Cell Res.252, 243-249. 2. Boehm, M. and Bonifacino, J. S. (2001). Adaptins. The final recount. Mol. Biol. Cell.12, 2907-2920. 3. Boulton, I. C. and Gray-Owen, S. D. (2002). Neisserial binding to CEACAM1 arrests the activation and proliferation of CD4+ T lymphocytes. Nat. Immunol.3, 229-236. 4. Boyer, B., Tucker, G. C., Vallés, A. M., Franke, W. W. and Thiery, J. P. (1989). Rearrangements of desmosomal and cytoskeletal proteins during the transition from epithelial to fibroblastoid organization in cultured rat bladder carcinoma cells. J. Cell Biol.109, 1495-1509. 5. Brümmer, J., Neumaier, M., Göpfert, C. and Wagener, C. (1995). Association of pp60c-src with biliary glycoprotein (CD66a), an adhesion molecule of the carcinoembryonic antigen family downregulated in colorectal carcinomas. Oncogene11, 1649-1655.
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