Fig. 7.
S-phase stress-response mechanisms. The timeless-tipin fork protection complex (FPCTim-Tip) is involved in the ATR-Chk1-dependent replication checkpoint. FPCTim-Tip has checkpoint-independent functions that are important for fork protection, DNA repair, and sister chromatid cohesion. In this model, FPCTim-Tip stabilizes replication forks in a configuration that is recognized by replication checkpoint sensors. In addition, FPCTim-Tip cooperates with ChlR1 to promote proper establishment of sister chromatid cohesion.