Tax, the human T cell leukemia virus type I oncoprotein, plays a crucial role in viral
transformation and the development of the virally associated disease adult T cell leukemia.
Because oncogenesis involves alterations in cell growth, it is important to examine the
effects of Tax on cell cycle progression. Using a synchronized cell system, we have found
that Tax expression accelerates G 1 phase progression and S phase entry with concomitant
DNA replication. This accelerated progression is accompanied by an earlier onset of cdk2 …