Extrusion of nuclei of murine suspension culture cells with microtubule poisons

Abstract

Microtubule poisons such as colchicine, colcemid and vinblastine caused extrusion of nuclei of murine suspension culture cells (mastocytoma p-815 cells, myeloma PU-3 cells, leukemia M1 cells). Enucleation did not follow spontaneously in most cells, but it did occur when the treated cells were centrifuged in Separate-L gradient. These poisons did not induce nuclear extrusion in cells growing in monolayer (L cells, BALB/c 3T3 cells, SV40-transformed BALB/c 3T3 cells, histiocytoma HC-11 cells). Cytochalasin B (CB) that had been reported to cause nuclear extrusion in the cells cultured in monolayer [1] did not induce the extrusion in the suspension culture cells but inhibited the colchicine-induced nuclear extrusion.