[Effect of protein synthesis inhibitors on DNA replication. I. Effect of the short-term action of cycloheximide on cell permeability for thymidine in vitro].

The effect of protein synthesis inhibitors on DNA replication was studied on L cells. After a 10 minutes' action of the inhibitors, protein synthesis was seen to be completely blocked, and DNA synthesis decreased by 85%. Four hours after a 20-minutes' cycloheximide treatment, the cells completely restored their ability to protein synthesis and DNA replication and even surpass the control level, due, probably, to a partial cell synchronization in S period. The short action of cycloheximide did not interfere with thymidine uptake by the cells. The rate of the exogenous precursor uptake was even higher than that in the control, apparently, because of its much reduced utilization in the inhibited DNA synthesis.