ISSN:
0886-1544
Keywords:
adherens junction
;
cytoskeleton
;
intercellular junction
;
tight junction
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
We previously reported the expression of ZO-1 in cell types that do not form tight junctions. Here we compare the molecular environments of ZO-1 in epithelial cells, primary cultures of astrocytes and in the non-epithelial S180 sarcoma cell line. ZO-1 co-localizes with a subset of actin filament in all cell types. In astrocytes, ZO-1 is found concentrated in discrete bands at points of cell-cell contact. Indirect immunofluorescent microscopy shows that these bands of ZO-1 co-localize with the adherens junction proteins vinculin and α-actinin, and with the antigen recognized by a pan-cadherin antibody. In contrast, ZO-1 in S180 cells, which exhibit limited cell-cell interactions, is diffusely distributed over the plasma membrane, with concentrations in lamellipodia where actin filaments accumulate. ZO-1 does not co-localize with vinculin at focal adhesions in this cell type. Analysis of ZO-1 immunoprecipitation profiles from different cell types, performed under conditions previously demonstrated to maintain interactions between ZO-1, ZO-2 and p130 from the MDCK epithelial cell line, show that the proteins which co-precipitate with ZO-1 vary with cell type. Precipitation of polypeptides at 165 kDa, potentially ZO-2, and 65 kDa occurs in both a mouse kidney tubule epithelial cell line and the non-epithelial S180 cells. No proteins specifically associate with ZO-1 immunoprecipitated from astrocytes. Spectrin, α-actinin, vinculin and cadherin are not detected in immunoblots of ZO-1 immunoprecipitates from any cell type. © 1995 Wiley-Liss, Inc.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cm.970310408
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