2-AMINOPURINE OVERRIDES A LATE TELOPHASE DELAY CREATED BY ECTOPIC EXPRESSION OF THE PITSLRE-BETA-1 PROTEIN-KINASE

Minimal overexpression of the PITSLREbeta1 protein kinase in CHO cells to a marked delay in late mitosis. We have previously shown that this delay is characterized by the presence of substantially increased num bers of tubulin midbodies, inhibition of cytokinesis, and numerous mul tinucleated and micronucleated cells. Others have shown that the prote in kinase inhibitor 2-aminopurine (2-AP) is capable of overriding drug induced cell cycle blocks. In this study we demonstrate that the late mitotic delay and altered cellular morphology caused by ectopic expre ssion of the PITSLREbeta1 protein kinase can be overcome by 2-aminopur ine treatment. Furthermore, 2-aminopurine inhibits PITSLREbeta1 protei n kinase activity in vivo, but does not effect p34cdc2 protein kinase activity in a similar manner. (C) 1994 Academic Press, Inc.