question: What is the role of the MCM2-7 complex?
answer: The MCM2-7 complex is a ring-shaped heterohexamer helicase, that unwinds the DNA double helix ahead of the other replication machinery. During pre-replication complex (pre-RC) formation, origin recognition complex (ORC), Cdc6, and Cdt1 cooperatively load a double-hexameric MCM2-7 complex onto DNA. Loading of MCM2-7 is a prerequisite for licensing of eukaryotic DNA replication. During S phase MCM2-7 functions as part of the replicative helicase but within the pre-RC MCM2-7 is inactive.