Specificity and valency of concanavalin A in neuron-substratum adhesion and redistribution of cell surface receptors.
Neurons seeded in culture as spherical cells flatten partially to form lamellipodia by which they adhere to the substratum. Lamellipodium formation is stimulated specifically by concanavalin A (Con A) and other mannose-binding lectins in several types of neuronal cells, but not in similarly treated fibroblasts. Conditions that block much of the adsorption of Con A to the substratum have no effect on stimulation of lamellipodium formation by Con A. This suggests that Con A acts in solution on neurons and does not directly bind them to their substrata. Succinylated-Con A (bivalent) binds to the same receptors as native Con A (tetravalent) but does not elicit lamellipodium extension unless crosslinked with anti-Con A IgG. Treatment of neurons with Con A produces local changes in the composition of the cell surface resulting from redistribution of lectin receptor complexes. This redistribution is not as great with SCon A and, like lamellipodium formation, is sensitive to the valency of Con A. A variety of treatments (4 degrees C, trifluoperazine, nordihydroguaiaretic acid, 4-bromphenacyl bromide, and cytochalasin D), inhibit both Con A-receptor redistribution and lamellipodium extension by neurons. Other treatments (colchicine and cycloheximide) prevented neither lamellipodium formation nor redistribution.
D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000276:immunology; D002642:Chick Embryo; D003208:Concanavalin A / Q000378:metabolism / Q000494:pharmacology*; D005727:Ganglia, Spinal / Q000166:cytology / Q000276:immunology; D005728:Ganglia, Sympathetic / Q000166:cytology / Q000276:immunology; D007700:Kinetics; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000276:immunology; D011952:Receptors, Concanavalin A / Q000378:metabolism; D013696:Temperature
D011952:Receptors, Concanavalin A; D003208:Concanavalin A