Fig. 3.
Isw2 and Ino80 attenuate S phase checkpoint activity and facilitate efficient checkpoint deactivation during and after HU treatment. (a) Flow cytometry analysis during and after transient HU treatment. WT and isw2 nhp10 cells were arrested in G1 and released into YPD containing 200 mM HU for 90 min. Then, cells were released into the S phase in YPD and collected at the indicated time points after release. Flow cytometry was performed as described for Fig. 2b. (b) Rad53 ISA assay during and after HU treatment. Cells were harvested during G1 arrest, every 30 min during HU treatment, and every 20 min during S phase recovery. The arrows show the Rad53 ISA band, and asterisks designate other kinases with ISA activity that served as a loading control. (c) Rad53 Western blot analysis during and after HU treatment. Western blot analysis of cells grown under transient HU conditions was performed as described for panel b. The blot was probed with anti-Rad53 and antitubulin antibodies.