part of cell cycle process protein-DNA complex assembly MCM complex loading https://github.com/geneontology/go-ontology/issues/16570 GO:0140530 biological_process The protein localization process in which two MCM complexes become associated with chromatin at replication origins. MCM loading begins when origin-bound ORC and Cdc6 (Cdc18 in fission yeast) recruit one MCM2-7/Cdt1 complex to the origin, includes formation of a succession of intermediate complexes and ATP hydrolysis-dependent Mcm2-7 ring closure, and ends when two MCM hexamers fully encircle DNA, and are oriented head-to-head. The double hexamer is inactive for DNA unwinding. MCM loading takes place during G1 phase, and precedes CMG complex assembly. MCM complex loading at replication origin MCM double hexamer formation at replication origin pg 2020-10-12T16:46:23Z nuclear cell cycle DNA replication initiation