DNA replication licensing factor, required for pre-replication complex assembly. Faithful duplication of the genetic material requires 'once per cell cycle' DNA replication initiation and elongation. Central to this control is the tightly regulated formation of prereplicative complexes (preRCs) at future origins of DNA replication. Required for the recruitment of the MCM2-7 helicase complex to the replication origins. Associates with the MCM2-7 complex. Interacts with MCM2, ORC1, ORC2 and ORC6. Undergoes cell cycle-dependent changes in its nuclear localization. Exits the nucleus and remains in the cytoplasm during S phase through early mitosis, and re-accumulates in the nucleus around the end of mitosis. Present with 2190 molecules/cell in log phase SD medium. Belongs to the Cdt1 family.