Characterization of the Colchicine Binding of Membrane Fractions from Rat and Mouse Liver

A variety of cytological studies have produced the concept that the antimitotic drugs colchicine and Colcemid bind to specific proteins, the "tubulins" (1, 3, 4, 20, 38, 42) . Moreover it has been implied in most of these studies that these "colchicine-binding proteins" are recovered in a soluble form, i .e ., in the 100,000 g supernate from a cellular homogenate . However, recently, colchicine-binding has been described for particulate cellular subfractions from various tissues,