Mouse Rif1 is a key regulator of the replication-timing program in mammalian cells

Thank you for submitting your manuscript on mouse Rif1 and replication timing for consideration by The EMBO Journal. It has now been evaluated by three referees, whose reports are copied below. While the all consider your findings as potentially important, interesting and timely, they at the same time find the study presently still preliminary, and raise a number of very substantive concerns that in our view preclude publication at the current stage. In particular, all referees remain unconvinced that the Rif1 deletion effects on BrdU incorporation in relation to S-phase length and cell cycle/Sphase stages have been conclusively established. Another major issue is the unclear relation of Rif1 deletion to replication origin licensing or activity as possible causes for replication timing alterations.