MCM6
Encyclopedia
DNA replication licensing factor MCM6 is a protein
that in humans is encoded by the MCM6 gene
. MCM6 is one of the highly conserved mini-chromosome maintenance proteins (MCM
) that are essential for the initiation of eukaryotic genome
replication
.
, 4
and 7
possesses DNA
helicase
activity, and may act as a DNA unwinding enzyme
. The hexameric protein complex formed by the MCM proteins is a key component of the 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 Cdt1 at defined residues, by mutating these target residues Wei et al. observed lack of Cdt1 recruitment of Mcm2-7 to the pre-RC.
s. There are 2 non overlapping alternative last exon
s. The transcript
s appear to differ by truncation of the 3' end, presence or absence of 2 cassette exons, common exons with different boundaries.
MCM6 produces, by alternative splicing
, 3 different transcripts, all with introns, putatively encoding 3 different protein isoforms.
MCM6 contains two of the regulatory regions for LCT
, the gene encoding the protein 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.
Mutation
s in these regions are associated with lactose tolerance into adult life.
with ORC1L, ORC2L
, Replication protein A1, ORC4L
, MCM4
, MCM7
, MCM2
and CDC45-related protein
.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the MCM6 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
. MCM6 is one of the highly conserved mini-chromosome maintenance proteins (MCM
Mini Chromosome Maintenance
Mini Chromosome Maintenance complex, or Minichromosome Maintenance protein complex or mini-chromosome maintenance 2-7 helicase complex has a role in both the initiation and the elongation phases of eukaryotic DNA replication, specifically the formation and elongation of the replication fork...
) that are essential for the initiation of eukaryotic genome
Genome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....
replication
DNA replication
DNA replication is a biological process that occurs in all living organisms and copies their DNA; it is the basis for biological inheritance. The process starts with one double-stranded DNA molecule and produces two identical copies of the molecule...
.
Function
The MCM complex consisting of MCM6 (this protein) and MCM2MCM2
DNA replication licensing factor MCM2 is a protein that in humans is encoded by the MCM2 gene.-Interactions:MCM2 has been shown to interact with Replication protein A1, AKAP8, MCM5, MCM6, MCM7, ORC1L, ORC2L, ORC4L, ORC5L, MCM4, MCM3 and Cell division cycle 7-related protein kinase.-Further reading:...
, 4
MCM4
DNA replication licensing factor MCM4 is a protein that in humans is encoded by the MCM4 gene.-Interactions:MCM4 has been shown to interact with ORC1L, ORC2L, Replication protein A1, ORC4L, ORC5L, ORC3L, MCM6, MCM7, MCM2, Cell division cycle 7-related protein kinase and ORC6L.-Further reading:...
and 7
MCM7
DNA replication licensing factor MCM7 is a protein that in humans is encoded by the MCM7 gene.-Interactions:MCM7 has been shown to interact with Replication protein A1, ORC3L, Retinoblastoma protein, MCM5, MCM6, ORC1L, ORC2L, ORC5L, MCM4, MCM3, CDC6, MNAT1, DBF4, MCM2, UBE3A, CDC45-related protein...
possesses DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
helicase
Helicase
Helicases are a class of enzymes vital to all living organisms. They are motor proteins that move directionally along a nucleic acid phosphodiester backbone, separating two annealed nucleic acid strands using energy derived from ATP hydrolysis.-Function:Many cellular processes Helicases are a...
activity, and may act as a DNA unwinding enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
. The hexameric protein complex formed by the MCM proteins is a key component of the pre-replication complex
Pre-replication complex
A pre-replication complex is a protein complex that forms at the origin of replication during the initiation step of DNA replication. Formation of the pre-RC is required for DNA replication to occur. Complete and faithful replication of the genome ensures that each daughter cell will carry the...
(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 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 intronIntron
An intron is any nucleotide sequence within a gene that is removed by RNA splicing to generate the final mature RNA product of a gene. The term intron refers to both the DNA sequence within a gene, and the corresponding sequence in RNA transcripts. Sequences that are joined together in the final...
s. There are 2 non overlapping alternative last exon
Exon
An exon is a nucleic acid sequence that is represented in the mature form of an RNA molecule either after portions of a precursor RNA have been removed by cis-splicing or when two or more precursor RNA molecules have been ligated by trans-splicing. The mature RNA molecule can be a messenger RNA...
s. The transcript
Transcript
Transcript may refer to:* Transcript , a copy of a student's permanent academic record* Transcription , the process of creating an equivalent RNA copy of a sequence of DNA* Transcript , a record of all court proceedings...
s appear to differ by truncation of the 3' end, presence or absence of 2 cassette exons, common exons with different boundaries.
MCM6 produces, by alternative splicing
Alternative splicing
Alternative splicing is a process by which the exons of the RNA produced by transcription of a gene are reconnected in multiple ways during RNA splicing...
, 3 different transcripts, all with introns, putatively encoding 3 different protein isoforms.
MCM6 contains two of the regulatory regions for LCT
Lactase
Lactase , a part of the β-galactosidase family of enzymes, is a glycoside hydrolase involved in the hydrolysis of the disaccharide lactose into constituent galactose and glucose monomers...
, the gene encoding the protein lactase
Lactase
Lactase , a part of the β-galactosidase family of enzymes, is a glycoside hydrolase involved in the hydrolysis of the disaccharide lactose into constituent galactose and glucose monomers...
, 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
Enhancer (genetics)
In genetics, an enhancer is a short region of DNA that can be bound with proteins to enhance transcription levels of genes in a gene cluster...
element capable of differentially activating transcription of LCT promoter.
Mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...
s in these regions are associated with lactose tolerance into adult life.
Interactions
MCM6 has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with ORC1L, ORC2L
ORC2L
Origin recognition complex subunit 2 is a protein that in humans is encoded by the ORC2L gene.-Interactions:ORC2L has been shown to interact with ORC1L, Replication protein A1, ORC4L, ORC5L, ORC3L, MCM4, CDC6, MCM5, MCM6, MCM7, MCM10, DBF4, MCM2 and ORC6L.-Further reading:...
, Replication protein A1, ORC4L
ORC4L
Origin recognition complex subunit 4 is a protein that in humans is encoded by the ORC4L gene.-Interactions:ORC4L has been shown to interact with ORC1L, MCM6, ORC2L, ORC5L, ORC3L, MCM2, MCM4, MCM3 and ORC6L.-Further reading:...
, MCM4
MCM4
DNA replication licensing factor MCM4 is a protein that in humans is encoded by the MCM4 gene.-Interactions:MCM4 has been shown to interact with ORC1L, ORC2L, Replication protein A1, ORC4L, ORC5L, ORC3L, MCM6, MCM7, MCM2, Cell division cycle 7-related protein kinase and ORC6L.-Further reading:...
, MCM7
MCM7
DNA replication licensing factor MCM7 is a protein that in humans is encoded by the MCM7 gene.-Interactions:MCM7 has been shown to interact with Replication protein A1, ORC3L, Retinoblastoma protein, MCM5, MCM6, ORC1L, ORC2L, ORC5L, MCM4, MCM3, CDC6, MNAT1, DBF4, MCM2, UBE3A, CDC45-related protein...
, MCM2
MCM2
DNA replication licensing factor MCM2 is a protein that in humans is encoded by the MCM2 gene.-Interactions:MCM2 has been shown to interact with Replication protein A1, AKAP8, MCM5, MCM6, MCM7, ORC1L, ORC2L, ORC4L, ORC5L, MCM4, MCM3 and Cell division cycle 7-related protein kinase.-Further reading:...
and CDC45-related protein
CDC45-related protein
CDC45 is a protein that in humans is encoded by the CDC45L gene.-Interactions:CDC45-related protein has been shown to interact with ORC1L, MCM6, MCM7, MCM3 and ORC6L.-Further reading:...
.