Colchicine permeation is required for inhibition of concanavalin A capping in Chinese hamster ovary cells.

Several antimitotic, tubulin-binding agents, such as colchicine, colcemid, and podophyllotoxin, inhibit the capping of fluorescent-labeled concanavalin A in Chinese hamster ovary cells. By comparing the effects of these agents on parental cell lines on several independently selected colchicine-resistant mutants with decreased drug permeability, we have demonstrated that permeation of these drugs in required for inhibition of capping. These data support the hypothesis that these antimitotic agents interact with an intracellular component, probably microtubules, to prevent the directional movement of concanavalin A receptors on the surface membranes of Chinese hamster ovary cells.