In order for any organism to replicate its DNA, a helicase must unwind the duplex DNA in front of the replication fork. In archaea, the replicative helicase is the MCM (minichromosome maintenance) helicase. Although much is known about the biochemical properties of the MCM helicase, the mechanism of assembly at the origin of replication is unknown. In the present paper, several possible mechanisms for the loading process are described.
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