Based on studies in budding yeast, once the initial complex of ORC(1-6), CDC6, CDT1 and MCM2-7 (OCCM) is formed, CDT1 is released from DNA in an ATP-dependent manner. The ATPase activity of CDC6 is necessary for CDT1 release, but ATPase activities of other ATPases in the complex (e.g. ORC1) may contribute to CDT1 release. ORC6 is necessary for the retention of MCM2-7 after ATP hydrolysis (Fernández-Cid et al. 2013).
ATP hydrolysis activity of ORC(1-6):CDC6:origin of replication:CDT1:MCM2-7 [nucleoplasm]