Closing the MCM cycle at replication termination sites

Abstract

The initiation of eukaryotic DNA replication is a highly regulated process conserved from yeast to human. The past decade has seen significant advances in understanding how the CMG (Cdc45‐ MCM ‐ GINS ) replicative helicase is loaded onto DNA . However, very little was known on how this complex is removed from chromatin at the end of S phase. Two papers in a recent issue of Science show that in yeast and in Xenopus , the CMG complex is unloaded at replication termination sites by an active mechanism involving the polyubiquitylation of Mcm7.