Fig. 1.

S-phase progression is inhibited in response to SDS. (A) Wild-type cells were arrested and released in G1-phase by α-factor. The cell cycle progression was monitored by FACS analysis in the presence or absence of 0.0075% SDS added at time 0 (red arrow) or 20 min after release (blue arrow). (B) First, cdc7-4 cells were arrested in G1-phase by α-factor at 23 °C and then released at 37 °C, the restrictive temperature, to block the cells after pre-RC formation but with an inactive helicase. Cells were then released into YPD media at 23 °C and collected every 20 min to monitor the cell cycle progression by FACS analysis in the presence or absence of SDS 0.0075% added at time 0 (green arrow). The diagrams below show at what point of the cycle that the cells were in when SDS was added.