Association of a transglutaminase-related antigen with intermediate filaments.
A mouse monoclonal antibody, G92.1.2, raised against guinea pig liver transglutaminase (TGase) recognizes an antigen present in primary mouse dermal fibroblasts. A filamentous pattern, bearing remarkable similarity to the vimentin intermediate filament (IF) network, is seen when these cells are fixed and processed for indirect immunofluorescence with the antibody. Double-label immunofluorescence reveals that the antigen reacting with the antibody colocalizes precisely with vimentin IF and that this colocalization is retained after the treatment of fibroblasts with colchicine, which induces a redistribution of the majority of IFs into perinuclear aggregates. These morphological observations are further supported by the finding that the protein reacting with G92.1.2 is retained in IF-enriched cytoskeletal preparations made by using nonionic detergent-containing high ionic strength solutions. Western blots of the IF fraction show that G92.1.2 recognizes a major band of approximately 280 kDa and does not cross react with vimentin. Furthermore, when the antibody is microinjected into live dermal fibroblasts, it causes a collapse of the vimentin IF network in the majority of injected cells. The results suggest that a form of TGase, or a TGase-related antigen, is closely associated with the vimentin IF network of primary cultures of mouse dermal fibroblasts.
Trejo-Skalli
A V
AV
Department of Cell and Molecular Biology, Northwestern University Medical School, Chicago, IL 60611, USA.
Velasco
P T
PT
Murthy
S N
SN
Lorand
L
L
Goldman
R D
RD
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000941:Antigens / Q000276:immunology; D017209:Apoptosis / Q000502:physiology; D002478:Cells, Cultured; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000276:immunology / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D006168:Guinea Pigs; D015151:Immunoblotting; D007382:Intermediate Filaments / Q000201:enzymology* / Q000276:immunology; D008099:Liver / Q000201:enzymology; D051379:Mice; D011487:Protein Conformation; D012867:Skin / Q000166:cytology / Q000276:immunology / Q000648:ultrastructure; D013347:Subcellular Fractions / Q000201:enzymology; D011503:Transglutaminases / Q000276:immunology / Q000302:isolation & purification*; D014746:Vimentin / Q000302:isolation & purification
D000911:Antibodies, Monoclonal; D000941:Antigens; D014746:Vimentin; D011503:Transglutaminases