Demonstration of type II hemidesmosomes in a mammary gland epithelial cell line, BMGE-H.
Hemidesmosomes (HDs) are specialized cell-substrate junctions with distinct cytoplasmic plaques where intermediate filaments (IFs) are anchored. In our previous work, we described two types of HDs in terms of their molecular constituents, i.e. type I HD and type II HD [Hieda, Y., Nishizawa, Y., Uematsu, J., & Owaribe, K. (1992) J. Cell Biol. 116, 1497-1506]. In the present study we further characterized type II HDs in cultured cells, comparing their composition and function with those of conventional type I HDs. Although the two bovine mammary gland epithelial cell lines, BMGE+H and BMGE-H, were derived from the same tissue, their cell-substrate adhesion properties are markedly different. Immunological examination showed that BMGE-H cells express HD1 and the integrin alpha 6 beta 4 complex but not bullous pemphigoid antigens, while BMGE+H cells express all these components, i.e. the former have type II HDs and the latter have type I HDs. GoH3, a monoclonal antibody to the integrin alpha 6 subunit, inhibited BMGE-H cell adhesion to laminin as a substrate, as also observed for BMGE+H cells. These and electron microscopic results indicate that BMGE-H cells form type II HD-like structures containing HD1 and alpha 6 beta 4 which are associated with IFs. This structure mediates adhesion of the cell to laminin. This is the first demonstration of an adhesion function for type II HDs in cultured cells.
Uematsu
J
J
Department of Molecular Biology, School of Science, Nagoya University.
Nishizawa
Y
Y
Sonnenberg
A
A
Owaribe
K
K
D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D001324:Autoantigens / Q000032:analysis; D001665:Binding Sites; D002352:Carrier Proteins; D002417:Cattle; D002448:Cell Adhesion; D002460:Cell Line; D003094:Collagen; D003598:Cytoskeletal Proteins; D003896:Desmosomes / Q000737:chemistry / Q000502:physiology / Q000648:ultrastructure*; D000071821:Dystonin; D004591:Electrophoresis, Polyacrylamide Gel; D015151:Immunoblotting; D039161:Integrin alpha6beta4; D016023:Integrins / Q000032:analysis; D007797:Laminin / Q000032:analysis; D008321:Mammary Glands, Animal / Q000648:ultrastructure*; D051379:Mice; D008856:Microscopy, Fluorescence; D009419:Nerve Tissue Proteins; D024041:Non-Fibrillar Collagens; D010391:Pemphigoid, Bullous / Q000276:immunology; D011233:Precipitin Tests; D000097805:Collagen Type XVII
D000954:Antigens, Surface; D001324:Autoantigens; D002352:Carrier Proteins; D003094:Collagen; D003598:Cytoskeletal Proteins; D000071821:Dystonin; D039161:Integrin alpha6beta4; D016023:Integrins; D007797:Laminin; D009419:Nerve Tissue Proteins; D024041:Non-Fibrillar Collagens; D000097805:Collagen Type XVII; C095667:Dst protein, mouse