Formation of the Apical Pole of Epithelial (Madin-Darby Canine Kidney) Cells: Polarity of an Apical Protein Is Independent of Tight Junctions While Segregation of a Basolateral Marker Requires Cell-Cell Interactions

• Published in: The Journal of cell biology 1987-04, Vol.104 (4), p.905-916
• Main Authors: Vega-Salas, Dora E., Pedro J. I. Salas, Gundersen, Doris, Rodriguez-Boulan, Enrique
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Monoclonal; Antigens; Biological and medical sciences; Calcium; Cell Communication; Cell culture techniques; Cell Line; Cell lines; Cell Membrane - physiology; Cell Membrane - ultrastructure; Cell membranes; Cell membranes. Ionic channels. Membrane pores; Cell structures and functions; Cells; Dogs; Epithelial Cells; Epithelium - physiology; Fluorescence; Fundamental and applied biological sciences. Psychology; Intercellular Junctions - physiology; Intercellular Junctions - ultrastructure; Kidney; Kidney cells; MDCK cells; membrane proteins; Membrane Proteins - analysis; Microscopy, Electron; Molecular and cellular biology; Molecular Weight; Tight junctions
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.104.4.905

The time course of development of polarity of an apical (184-kD) and a basolateral (63-kD) plasma membrane protein of Madin-Darby canine kidney cells was followed using semiquantitative immunofluorescence on semithin (∼0.5-μm) frozen sections and monoclonal antibody probes. The 184-kD protein became highly polarized to the apical pole within the initial 24 h both in normal medium and in 1-5 μM Ca2+, which results in well-spread, dome-shaped cells, lacking tight junctions and other lateral membrane interactions. In contrast, the basolateral 63-kD membrane protein developed full polarity only after incubation in normal Ca2+concentrations for >72 h, a time much longer than that required for the formation of tight junctions (∼18 h) and failed to polarize in 1-5 μM Ca2+. These results demonstrate that intradomain restriction mechanisms independent of tight junctions, such as self-aggregation or specific interactions with the submembrane cytoskeleton, participate in the regionalization of at least some epithelial plasma membrane proteins. The full operation of these mechanisms depends on the presence of normal cell-cell interactions in the case of the basolateral 63-kD antigen but not in the case of the apical 184-kD protein.