Actin cytoskeletal lesions in differentiated human colon carcinoma Caco-2 cells after exposure to soybean agglutinin.
We have investigated the effects of soybean agglutinin on the cytoskeletal element actin in differentiated Caco-2 cells. The actin cytoskeleton of the cells was visualized by fluorescence microscopy using 7-nitrobenz-2-oxa-1, 3-diazole phallacidin as a specific marker for F-actin. Compared with control Caco-2 cells no changes in the fluorescence pattern were observed after incubation with soybean agglutinin. However, using the deoxyribonuclease-I inhibition assay a dose-related response was noted in the increase of intracellular G-actin after a 2-hour incubation period with soybean agglutinin. Already after exposure for 15 min to soybean agglutinin a decrease in intracellular F-actin was demonstrable. This apparent depolymerization could be prevented by incubating the Caco-2 cells with soybean agglutinin and the appropriate monosaccharide simultaneously. The increase in the amount of G-actin appeared to be correlated with a shortening of microvilli on the Caco-2 cells.
Draaijer
M
M
Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Utrecht, The Netherlands.
Koninkx
J
J
Hendriks
H
H
Kik
M
M
Van Dijk
J
J
Mouwen
J
J
D000199:Actins / Q000032:analysis*; D002454:Cell Differentiation; D003110:Colonic Neoplasms / Q000473:pathology / Q000648:ultrastructure*; D003599:Cytoskeleton / Q000187:drug effects / Q000648:ultrastructure*; D006801:Humans; D037102:Lectins / Q000494:pharmacology*; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence / Q000379:methods; D008871:Microvilli / Q000187:drug effects / Q000648:ultrastructure; D037121:Plant Lectins; D030262:Soybean Proteins; D013025:Glycine max; D014407:Tumor Cells, Cultured / Q000648:ultrastructure*; D010835:Phytohemagglutinins
D000199:Actins; D037102:Lectins; D037121:Plant Lectins; D030262:Soybean Proteins; C028824:soybean lectin; D010835:Phytohemagglutinins