Inhibition of tubulin assembly by antileprosy drug dapsone.

The effect of dapsone on assembly-disassembly process of bovine brain tubulin was examined. The drug was found to readily bind tubulin dimer and that in its presence colchicine binding to tubulin was enhanced. Although dapsone associated with tubulin at a site other than the colchicine binding site, distinct inhibition of microtubule assembly was detected.