The MCM3 protein (minichromosome maintenance protein 3) is a 110 kD DNA-dependent ATPase containing a nuclear localization sequence. The MCM3 protein is a component of the DNA pre-replication complex that acts to allow DNA to undergo single round of replication per cell cycle. MCM3 is constitutively expressed and can be modified by acetylation. Acetylation of MCM3 inhibits the initiation of DNA replication. MCM3 has been reported to interact with the MCM5 (CDC46) and MCM3AP proteins. The Poly6023 antibody recognizes both human and mouse MCM3 and has been shown to be useful for Western blotting.