Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
Eukaryotes have six minichromosome maintenance (MCM) proteins that are essential for DNA replication. The contribution of ATPase activity of MCM complexes to their function in replication is poorly understood. We have established a cell-free system competent for replication in which all MCM proteins are supplied by purified recombinant Xenopus MCM complexes. Recombinant MCM2-7 complex was able to assemble onto chromatin, load Cdc45 onto chromatin, and restore DNA replication in MCM-depleted extracts. Using mutational analysis in the Walker A motif of MCM6 and MCM7 of MCM2-7, we show that ATP binding and/or hydrolysis by MCM proteins is dispensable for chromatin loading and pre-replicative complex (pre-RC) assembly, but is required for origin unwinding during DNA replication. Moreover, this ATPase-deficient mutant complex did not support DNA replication in MCM-depleted extracts. Altogether, these results both demonstrate the ability of recombinant MCM proteins to perform all replication roles of MCM complexes, and further support the model that MCM2-7 is the replicative helicase. These data establish that mutations affecting the ATPase activity of the MCM complex uncouple its role in pre-RC assembly from DNA replication.
Aparicio,
Components and dynamics of DNA replication complexes in S. cerevisiae: redistribution of MCM proteins and Cdc45p during S phase.
1997, Pubmed
Aparicio,
Components and dynamics of DNA replication complexes in S. cerevisiae: redistribution of MCM proteins and Cdc45p during S phase.
1997,
Pubmed
Bailis,
MCM proteins: DNA damage, mutagenesis and repair.
2004,
Pubmed
Bell,
DNA replication in eukaryotic cells.
2002,
Pubmed
Blow,
Initiation of DNA replication in nuclei and purified DNA by a cell-free extract of Xenopus eggs.
1986,
Pubmed
,
Xenbase
Blow,
Replication origins in Xenopus egg extract Are 5-15 kilobases apart and are activated in clusters that fire at different times.
2001,
Pubmed
,
Xenbase
Chong,
A double-hexamer archaeal minichromosome maintenance protein is an ATP-dependent DNA helicase.
2000,
Pubmed
Chong,
Purification of an MCM-containing complex as a component of the DNA replication licensing system.
1995,
Pubmed
,
Xenbase
Cortez,
Minichromosome maintenance proteins are direct targets of the ATM and ATR checkpoint kinases.
2004,
Pubmed
Davey,
Reconstitution of the Mcm2-7p heterohexamer, subunit arrangement, and ATP site architecture.
2003,
Pubmed
Diffley,
Two steps in the assembly of complexes at yeast replication origins in vivo.
1994,
Pubmed
,
Xenbase
Edwards,
MCM2-7 complexes bind chromatin in a distributed pattern surrounding the origin recognition complex in Xenopus egg extracts.
2002,
Pubmed
,
Xenbase
Fletcher,
The structure and function of MCM from archaeal M. Thermoautotrophicum.
2003,
Pubmed
Forsburg,
Eukaryotic MCM proteins: beyond replication initiation.
2004,
Pubmed
Fujita,
In vivo interaction of human MCM heterohexameric complexes with chromatin. Possible involvement of ATP.
1997,
Pubmed
Gilbert,
Making sense of eukaryotic DNA replication origins.
2001,
Pubmed
Gómez,
Different phenotypes in vivo are associated with ATPase motif mutations in Schizosaccharomyces pombe minichromosome maintenance proteins.
2002,
Pubmed
Hendrickson,
Phosphorylation of MCM4 by cdc2 protein kinase inhibits the activity of the minichromosome maintenance complex.
1996,
Pubmed
,
Xenbase
Hyrien,
Paradoxes of eukaryotic DNA replication: MCM proteins and the random completion problem.
2003,
Pubmed
Hyrien,
Chromosomal replication initiates and terminates at random sequences but at regular intervals in the ribosomal DNA of Xenopus early embryos.
1993,
Pubmed
,
Xenbase
Ishimi,
A DNA helicase activity is associated with an MCM4, -6, and -7 protein complex.
1997,
Pubmed
Jares,
Xenopus cdc7 function is dependent on licensing but not on XORC, XCdc6, or CDK activity and is required for XCdc45 loading.
2000,
Pubmed
,
Xenbase
Kaplan,
Mcm4,6,7 uses a "pump in ring" mechanism to unwind DNA by steric exclusion and actively translocate along a duplex.
2003,
Pubmed
Kelman,
The single minichromosome maintenance protein of Methanobacterium thermoautotrophicum DeltaH contains DNA helicase activity.
1999,
Pubmed
Koonin,
A common set of conserved motifs in a vast variety of putative nucleic acid-dependent ATPases including MCM proteins involved in the initiation of eukaryotic DNA replication.
1993,
Pubmed
Kubota,
Licensing of DNA replication by a multi-protein complex of MCM/P1 proteins in Xenopus eggs.
1997,
Pubmed
,
Xenbase
Labib,
Uninterrupted MCM2-7 function required for DNA replication fork progression.
2000,
Pubmed
Lee,
Isolation and characterization of various complexes of the minichromosome maintenance proteins of Schizosaccharomyces pombe.
2000,
Pubmed
Madine,
MCM3 complex required for cell cycle regulation of DNA replication in vertebrate cells.
1995,
Pubmed
,
Xenbase
Mahbubani,
Cell cycle regulation of the replication licensing system: involvement of a Cdk-dependent inhibitor.
1997,
Pubmed
,
Xenbase
Maine,
Mutants of S. cerevisiae defective in the maintenance of minichromosomes.
1984,
Pubmed
Maiorano,
MCM8 is an MCM2-7-related protein that functions as a DNA helicase during replication elongation and not initiation.
2005,
Pubmed
,
Xenbase
Masuda,
CDK- and Cdc45-dependent priming of the MCM complex on chromatin during S-phase in Xenopus egg extracts: possible activation of MCM helicase by association with Cdc45.
2003,
Pubmed
,
Xenbase
Mimura,
Central role for cdc45 in establishing an initiation complex of DNA replication in Xenopus egg extracts.
2000,
Pubmed
,
Xenbase
Mimura,
Xenopus Cdc45-dependent loading of DNA polymerase alpha onto chromatin under the control of S-phase Cdk.
1998,
Pubmed
,
Xenbase
Moir,
Cold-sensitive cell-division-cycle mutants of yeast: isolation, properties, and pseudoreversion studies.
1982,
Pubmed
Murray,
Cell cycle extracts.
1991,
Pubmed
Pacek,
A requirement for MCM7 and Cdc45 in chromosome unwinding during eukaryotic DNA replication.
2004,
Pubmed
,
Xenbase
Pape,
Hexameric ring structure of the full-length archaeal MCM protein complex.
2003,
Pubmed
Patel,
Structure and function of hexameric helicases.
2000,
Pubmed
Prokhorova,
Sequential MCM/P1 subcomplex assembly is required to form a heterohexamer with replication licensing activity.
2000,
Pubmed
,
Xenbase
Schwacha,
Interactions between two catalytically distinct MCM subgroups are essential for coordinated ATP hydrolysis and DNA replication.
2001,
Pubmed
Shechter,
The intrinsic DNA helicase activity of Methanobacterium thermoautotrophicum delta H minichromosome maintenance protein.
2000,
Pubmed
Shechter,
MCM proteins and checkpoint kinases get together at the fork.
2004,
Pubmed
,
Xenbase
Shechter,
DNA unwinding is an Mcm complex-dependent and ATP hydrolysis-dependent process.
2004,
Pubmed
,
Xenbase
Takahashi,
Fission yeast minichromosome loss mutants mis cause lethal aneuploidy and replication abnormality.
1994,
Pubmed
Tercero,
DNA synthesis at individual replication forks requires the essential initiation factor Cdc45p.
2000,
Pubmed
Tye,
MCM proteins in DNA replication.
1999,
Pubmed
Walter,
Initiation of eukaryotic DNA replication: origin unwinding and sequential chromatin association of Cdc45, RPA, and DNA polymerase alpha.
2000,
Pubmed
,
Xenbase
Walter,
Regulation of replicon size in Xenopus egg extracts.
1997,
Pubmed
,
Xenbase
Walter,
Evidence for sequential action of cdc7 and cdk2 protein kinases during initiation of DNA replication in Xenopus egg extracts.
2000,
Pubmed
,
Xenbase
You,
Roles of Mcm7 and Mcm4 subunits in the DNA helicase activity of the mouse Mcm4/6/7 complex.
2002,
Pubmed
Yu,
The Methanobacterium thermoautotrophicum MCM protein can form heptameric rings.
2002,
Pubmed
Zou,
Formation of a preinitiation complex by S-phase cyclin CDK-dependent loading of Cdc45p onto chromatin.
1998,
Pubmed