Fig. 3: The Mms22-Rtt107 axis acts in parallel to the Slx4-Rtt107 axis in checkpoint dampening.

a mms22^RIM and slx4^TTS are additive in delaying the exit from the G2/M phase after transient exposure to MMS. Experiments were done as in Fig. 1c. Left: FACS profiles of indicated strains, with arrows highlighting differences among WT and mutant cells  toward the end of the time course. Right: percentages of cells that have exited the G2/M phase at the 300 min time point of the experiment were calculated based on three biological replicates, with averages and SEMs indicated. Statistical analysis was performed by one-tailed unpaired Student’s t-test. b mms22^RIM and slx4^TTS show additive effects for increasing the levels of active Rad53. Experiments were done as in Fig. 1d. Top: representative immunoblotting results detecting Rad53 phosphorylation at indicated time points. Tubulin served as the loading control. Bottom: relative levels of phosphorylated Rad53 were calculated based on three biological replicates, with averages and SEMs indicated. Statistical analysis was determined by one-tailed unpaired Student’s t-test. c mms22^RIM and slx4^RIM are additive in causing MMS sensitivity. Experiments were done as in Fig. 1b. d The effects of mms22^RIM and slx4^RIM on the chromatin association of Mms22 and Slx4. Sir2 and Tubulin were used to mark chromatin-bound (Chr) and non-chromatin (supernatant or Sup) fractions, respectively. WCE whole-cell extract. Left: cells contained Flag-tagged Mms22 and Slx4. Right: cells contained HA-tagged Mms22 and TAP-tagged Slx4. Cells were examined without MMS treatment. The experiments were conducted using two biological samples per genotype with similar results observed. e A model to summarize the Mms22-Rtt107 and Slx4-Rtt107 pathways in checkpoint dampening as suggested by our data presented in Figs. 1–3. Source data are provided as a Source Data file.