Colcemid Sensitivity of Fission Yeast

In an a t t empt to unders t and the regulat ion of chromosome segregation and cell division in eukaryotic cells, we are examining the inhib i t ion of cell division of the fission yeast Schzzosaccharomyces pombe by the ant imitot ic drug Colcemid (N-deacetyl-N-methylcolchicine, Ciba Pharmaceu t ica l C o , Summit , N. J . ) (1). Our approaches include a study of the physiological parameters accompanying inhibi t ion by Colcemid, a genetic study of mutan t s resistant to the drug, and an analysis of b inding of the drug to prote in fractions from sensitive and resistant strains of this yeast. In the present paper , we repor t on the sensitivity to Colcemid of different stages in the cell cycle of synchronous cultures of & pombe.