Inhibition of intercellular adhesion by concanavalin A is associated with concanavalin A-mediated redistribution of surface receptors.
The inhibition of adhesion between aggregates and layers of embryonic retinal cells by concanavalin A (Con A) and Con A-mediated rearrangements of Con A receptors on retinal cells were studied. A short incubation of aggregates and layers with 10 micrograms/ml Con A substantially reduced aggregate-to-layer adhesion in a subsequent assay without soluble lectin present. This effect of Con A was dose-dependent, temperature-sensitive, involved events subsequent to Con A binding, and was reduced by cytochalasin B. The inhibition produced by succinylated Con A was substantially increased by incubation with antibody to Con A. Visualization of ConA- receptor complexes by fluorescence microscopy revealed that binding of Con A induced clearing of Con A receptors from filopodia, flattened regions of growth cones, and the edges of axons. This clearing reaction was prevented by the same agents that reduced Con A's inhibition of cell adhesion: low temperature, succinylation of Con A, or cytochalasin B. Aggregate-layer adhesion was restored by releasing Con A at 37 degrees C. Inhibitors of protein and ATP synthesis did not prevent recovery of ability to make adhesions. However, release of Con A at lowered temperatures did not prevent recovery. The results suggest that intercellular adhesion is inhibited by events associated with redistribution of Con A-receptor complexes on retinal cells.
D001386:Azides / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects*; D002478:Cells, Cultured; D003078:Colchicine / Q000494:pharmacology; D003208:Concanavalin A / Q000031:analogs & derivatives / Q000494:pharmacology*; D003571:Cytochalasin B / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D008766:Methylmannosides / Q000494:pharmacology; D011952:Receptors, Concanavalin A / Q000502:physiology*; D011955:Receptors, Drug / Q000502:physiology*; D013696:Temperature
D001386:Azides; D008766:Methylmannosides; D011952:Receptors, Concanavalin A; D011955:Receptors, Drug; D003208:Concanavalin A; D003571:Cytochalasin B; D003078:Colchicine