The Journal of Membrane Biology

, Volume 203, Issue 1, pp 21–30

Association of α-Dystrobrevin with Reorganizing Tight Junctions

Article

DOI: 10.1007/s00232-004-0728-1

Cite this article as:
Sjö, A., Magnusson, K. & Peterson, K. J Membrane Biol (2005) 203: 21. doi:10.1007/s00232-004-0728-1

Abstract

Alpha-dystrobrevin (α-DB) has been described primarily as a cytoplasmic component of the dystrophin-glycoprotein complex in skeletal muscle cells. Isoforms of α-DB show different localization in cells and tissues; at basolateral membranes in epithelial cells, dystrobrevins mediate contact with the extracellular matrix, peripheral and transmembrane proteins and the filamentous actin cytoskeleton. Beside their structural role, α-DBs are assumed to be important in cell signalling and cell differentiation. We have primarily assessed the role of α-DB in two epithelial cell lines (MDCK I, HT 29), which represent different developmental stages and exhibit distinct permeability characteristics. Using a polyclonal anti-α-DB antibody, we have investigated its expression, localization and association with tight junction (TJ)- associated proteins (ZO-1, occludin) before and after protein kinase C (PKC) activation with phorbol myristate acetate. Distinct subsets of α-DB isoforms were detected in the two cell lines by immunoblotting. In both cell lines there was submembranous localization of α-DB both apically and basolaterally, shown with confocal imaging. PKC activation caused a reorganization of TJ, which was parallel to increased localization of α-DB to TJ areas, most pronounced in MDCK I cells. Moreover, actin and ZO-1 co-immunoprecipitated with a-DB, as displayed with immunoblotting. Our findings suggest that a-dystrobrevin specifically is associated with the tight junctions during their reorganization.

Keywords

Dystrobrevin Tight junction Protein kinase C Epithelium Dystrophin-glycoprotein 

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Division of Medical Microbiology, Department of Molecular and Clinical Medicine, Faculty of Health Sciences Linköping UniversitySweden