Structural mechanism for replication origin binding and remodeling by a metazoan origin recognition complex and its co-loader Cdc6

Abstract

The origin recognition complex (ORC) is essential for loading the Mcm2–7 replicative helicase onto DNA during DNA replication initiation. Here, the authors describe several cryo-electron microscopy structures of Drosophila ORC bound to DNA and its cofactor Cdc6 and also report an in vitro reconstitution system for Drosophila Mcm2–7 loading, revealing unexpected features of ORC’s DNA binding and remodeling mechanism during Mcm2–7 loading.