MCM6

DNA replication licensing factor MCM6 is a is_associated_with::protein that in humans is encoded by the MCM6 is_associated_with::gene. MCM6 is one of the highly conserved mini-chromosome maintenance proteins (MCM) that are essential for the initiation of is_associated_with::eukaryotic is_associated_with::genome replication.

Function
The MCM complex consisting of MCM6 (this protein) and is_associated_with::MCM2, 4 and 7 possesses is_associated_with::DNA is_associated_with::helicase activity, and may act as a DNA unwinding is_associated_with::enzyme. The hexameric protein complex formed by the MCM proteins is a key component of the is_associated_with::pre-replication complex (pre-RC) and may be involved in the formation of replication forks and in the recruitment of other DNA replication related proteins. The phosphorylation of the complex by CDC2 kinase reduces the helicase activity, suggesting a role in the regulation of DNA replication. Mcm 6 has recently been shown to interact strongly is_associated_with::Cdt1 at defined residues, by mutating these target residues Wei et al. observed lack of Cdt1 recruitment of Mcm2-7 to the pre-RC.

Gene
The MCM6 gene, MCM6, is expressed at very high level. MCM6 contains 18 is_associated_with::introns. There are 2 non overlapping alternative last is_associated_with::exons. The transcripts appear to differ by truncation of the 3' end, presence or absence of 2 cassette exons, common exons with different boundaries.

MCM6 produces, by is_associated_with::alternative splicing, 3 different transcripts, all with introns, putatively encoding 3 different protein is_associated_with::isoforms.

MCM6 contains two of the regulatory regions for LCT, the gene encoding the protein is_associated_with::lactase, located in two of the MCM6 introns, approximately 14 kb (-13910) and 22 kb (-22018) upstream of LCT. The (-13910) region, in particular, has been shown to function in vitro as an enhancer element capable of differentially activating transcription of LCT promoter.

is_associated_with::Mutations in these regions are associated with is_associated_with::lactose tolerance into adult life.

Interactions
MCM6 has been shown to interact with:


 * is_associated_with::CDC45-related protein,
 * is_associated_with::MCM2,
 * is_associated_with::MCM4,
 * is_associated_with::MCM7,
 * is_associated_with::ORC1L,
 * is_associated_with::ORC2L,
 * is_associated_with::ORC4L, and
 * is_associated_with::Replication protein A1.