| Structural highlights
Function
[MCM7_YEAST] Acts as component of the MCM2-7 complex (MCM complex) which is the putative replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. The active ATPase sites in the MCM2-7 ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The six ATPase active sites, however, are likely to contribute differentially to the complex helicase activity. Once loaded onto DNA, double hexamers can slide on dsDNA in the absence of ATPase activity.[1] [2] [CDC45_YEAST] Required for initiation of chromosomal DNA replication. Acts at the origin of replication. Also has a role in minichromosome maintenance.[3] [4] [MCM5_YEAST] Acts as component of the MCM2-7 complex (MCM complex) which is the putative replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. The active ATPase sites in the MCM2-7 ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The six ATPase active sites, however, are likely to contribute differentially to the complex helicase activity; specifically the MCM2-MCM5 association is proposed to be reversible and to mediate a open ring conformation which may facilitate DNA loading. Once loaded onto DNA, double hexamers can slide on dsDNA in the absence of ATPase activity.[5] [6] [PSF1_YEAST] Required for DNA replication. Functions as part of the GINS complex which plays an essential role in the initiation of DNA replication by binding to DNA replication origins and facilitating the assembly of the DNA replication machinery. Required for the chromatin binding of CDC45.[7] [PSF3_YEAST] Functions as part of the GINS complex which plays an essential role in the initiation of DNA replication by binding to DNA replication origins and facilitating the assembly of the DNA replication machinery.[UniProtKB:P40359][8] [MCM4_YEAST] Acts as component of the MCM2-7 complex (MCM complex) which is the putative replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. The active ATPase sites in the MCM2-7 ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The six ATPase active sites, however, are likely to contribute differentially to the complex helicase activity. Once loaded onto DNA, double hexamers can slide on dsDNA in the absence of ATPase activity. Required for S phase execution.[9] [10] [DPB2_YEAST] DNA polymerase epsilon (DNA polymerase II) participates in chromosomal DNA replication. It is required during synthesis of the leading and lagging DNA strands at the replication fork and binds at/or near replication origins and moves along DNA with the replication fork. It has 3'-5' proofreading exonuclease activity that correct errors arising during DNA replication. It is also involved in DNA synthesis during DNA repair.[11] [PSF2_YEAST] Functions as part of the GINS complex which plays an essential role in the initiation of DNA replication by binding to DNA replication origins and facilitating the assembly of the DNA replication machinery.[12] [MCM6_YEAST] Acts as component of the MCM2-7 complex (MCM complex) which is the putative replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. The active ATPase sites in the MCM2-7 ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The six ATPase active sites, however, are likely to contribute differentially to the complex helicase activity. Once loaded onto DNA, double hexamers can slide on dsDNA in the absence of ATPase activity. Required for the entry in S phase and for cell division.[13] [14] [MCM3_YEAST] Acts as component of the MCM2-7 complex (MCM complex) which is the putative replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. The active ATPase sites in the MCM2-7 ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The six ATPase active sites, however, are likely to contribute differentially to the complex helicase activity. Once loaded onto DNA, double hexamers can slide on dsDNA in the absence of ATPase activity. Necessary for cell growth.[15] [16] [SLD5_YEAST] Required for DNA replication. Functions as part of the GINS complex which plays an essential role in the initiation of DNA replication by binding to DNA replication origins and facilitating the assembly of the DNA replication machinery.[17] [UniProtKB:P40359] [DPOE_YEAST] DNA polymerase epsilon (DNA polymerase II) participates in chromosomal DNA replication. It is required during synthesis of the leading and lagging DNA strands at the replication fork and binds at/or near replication origins and moves along DNA with the replication fork. It has 3'-5' proofreading exonuclease activity that correct errors arising during DNA replication. It is also involved in DNA synthesis during DNA repair.[18] [MCM2_YEAST] Acts as component of the MCM2-7 complex (MCM complex) which is the putative replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. The active ATPase sites in the MCM2-7 ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The six ATPase active sites, however, are likely to contribute differentially to the complex helicase activity; specifically the MCM2-MCM5 association is proposed to be reversible and to mediate a open ring conformation which may facilitate DNA loading. Once loaded onto DNA, double hexamers can slide on dsDNA in the absence of ATPase activity. Necessary for cell growth.[19] [20]
Publication Abstract from PubMed
Eukaryotic origin firing depends on assembly of the Cdc45-MCM-GINS (CMG) helicase. A key step is the recruitment of GINS that requires the leading-strand polymerase Pol epsilon, composed of Pol2, Dpb2, Dpb3, Dpb4. While a truncation of the catalytic N-terminal Pol2 supports cell division, Dpb2 and C-terminal Pol2 (C-Pol2) are essential for viability. Dpb2 and C-Pol2 are non-catalytic modules, shown or predicted to be related to an exonuclease and DNA polymerase, respectively. Here, we present the cryo-EM structure of the isolated C-Pol2/Dpb2 heterodimer, revealing that C-Pol2 contains a DNA polymerase fold. We also present the structure of CMG/C-Pol2/Dpb2 on a DNA fork, and find that polymerase binding changes both the helicase structure and fork-junction engagement. Inter-subunit contacts that keep the helicase-polymerase complex together explain several cellular phenotypes. At least some of these contacts are preserved during Pol epsilon-dependent CMG assembly on path to origin firing, as observed with DNA replication reconstituted in vitro.
Structure of DNA-CMG-Pol epsilon elucidates the roles of the non-catalytic polymerase modules in the eukaryotic replisome.,Goswami P, Abid Ali F, Douglas ME, Locke J, Purkiss A, Janska A, Eickhoff P, Early A, Nans A, Cheung AMC, Diffley JFX, Costa A Nat Commun. 2018 Nov 29;9(1):5061. doi: 10.1038/s41467-018-07417-1. PMID:30498216[21]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Remus D, Beuron F, Tolun G, Griffith JD, Morris EP, Diffley JF. Concerted loading of Mcm2-7 double hexamers around DNA during DNA replication origin licensing. Cell. 2009 Nov 13;139(4):719-30. doi: 10.1016/j.cell.2009.10.015. Epub 2009 Nov, 5. PMID:19896182 doi:http://dx.doi.org/10.1016/j.cell.2009.10.015
- ↑ Evrin C, Clarke P, Zech J, Lurz R, Sun J, Uhle S, Li H, Stillman B, Speck C. A double-hexameric MCM2-7 complex is loaded onto origin DNA during licensing of eukaryotic DNA replication. Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20240-5. doi:, 10.1073/pnas.0911500106. Epub 2009 Nov 12. PMID:19910535 doi:http://dx.doi.org/10.1073/pnas.0911500106
- ↑ Hopwood B, Dalton S. Cdc45p assembles into a complex with Cdc46p/Mcm5p, is required for minichromosome maintenance, and is essential for chromosomal DNA replication. Proc Natl Acad Sci U S A. 1996 Oct 29;93(22):12309-14. PMID:8901577
- ↑ Zou L, Mitchell J, Stillman B. CDC45, a novel yeast gene that functions with the origin recognition complex and Mcm proteins in initiation of DNA replication. Mol Cell Biol. 1997 Feb;17(2):553-63. PMID:9001208
- ↑ Remus D, Beuron F, Tolun G, Griffith JD, Morris EP, Diffley JF. Concerted loading of Mcm2-7 double hexamers around DNA during DNA replication origin licensing. Cell. 2009 Nov 13;139(4):719-30. doi: 10.1016/j.cell.2009.10.015. Epub 2009 Nov, 5. PMID:19896182 doi:http://dx.doi.org/10.1016/j.cell.2009.10.015
- ↑ Evrin C, Clarke P, Zech J, Lurz R, Sun J, Uhle S, Li H, Stillman B, Speck C. A double-hexameric MCM2-7 complex is loaded onto origin DNA during licensing of eukaryotic DNA replication. Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20240-5. doi:, 10.1073/pnas.0911500106. Epub 2009 Nov 12. PMID:19910535 doi:http://dx.doi.org/10.1073/pnas.0911500106
- ↑ Takayama Y, Kamimura Y, Okawa M, Muramatsu S, Sugino A, Araki H. GINS, a novel multiprotein complex required for chromosomal DNA replication in budding yeast. Genes Dev. 2003 May 1;17(9):1153-65. PMID:12730134 doi:http://dx.doi.org/10.1101/gad.1065903
- ↑ Takayama Y, Kamimura Y, Okawa M, Muramatsu S, Sugino A, Araki H. GINS, a novel multiprotein complex required for chromosomal DNA replication in budding yeast. Genes Dev. 2003 May 1;17(9):1153-65. PMID:12730134 doi:http://dx.doi.org/10.1101/gad.1065903
- ↑ Remus D, Beuron F, Tolun G, Griffith JD, Morris EP, Diffley JF. Concerted loading of Mcm2-7 double hexamers around DNA during DNA replication origin licensing. Cell. 2009 Nov 13;139(4):719-30. doi: 10.1016/j.cell.2009.10.015. Epub 2009 Nov, 5. PMID:19896182 doi:http://dx.doi.org/10.1016/j.cell.2009.10.015
- ↑ Evrin C, Clarke P, Zech J, Lurz R, Sun J, Uhle S, Li H, Stillman B, Speck C. A double-hexameric MCM2-7 complex is loaded onto origin DNA during licensing of eukaryotic DNA replication. Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20240-5. doi:, 10.1073/pnas.0911500106. Epub 2009 Nov 12. PMID:19910535 doi:http://dx.doi.org/10.1073/pnas.0911500106
- ↑ Shimizu K, Hashimoto K, Kirchner JM, Nakai W, Nishikawa H, Resnick MA, Sugino A. Fidelity of DNA polymerase epsilon holoenzyme from budding yeast Saccharomyces cerevisiae. J Biol Chem. 2002 Oct 4;277(40):37422-9. Epub 2002 Jul 17. PMID:12124389 doi:http://dx.doi.org/10.1074/jbc.M204476200
- ↑ Takayama Y, Kamimura Y, Okawa M, Muramatsu S, Sugino A, Araki H. GINS, a novel multiprotein complex required for chromosomal DNA replication in budding yeast. Genes Dev. 2003 May 1;17(9):1153-65. PMID:12730134 doi:http://dx.doi.org/10.1101/gad.1065903
- ↑ Remus D, Beuron F, Tolun G, Griffith JD, Morris EP, Diffley JF. Concerted loading of Mcm2-7 double hexamers around DNA during DNA replication origin licensing. Cell. 2009 Nov 13;139(4):719-30. doi: 10.1016/j.cell.2009.10.015. Epub 2009 Nov, 5. PMID:19896182 doi:http://dx.doi.org/10.1016/j.cell.2009.10.015
- ↑ Evrin C, Clarke P, Zech J, Lurz R, Sun J, Uhle S, Li H, Stillman B, Speck C. A double-hexameric MCM2-7 complex is loaded onto origin DNA during licensing of eukaryotic DNA replication. Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20240-5. doi:, 10.1073/pnas.0911500106. Epub 2009 Nov 12. PMID:19910535 doi:http://dx.doi.org/10.1073/pnas.0911500106
- ↑ Remus D, Beuron F, Tolun G, Griffith JD, Morris EP, Diffley JF. Concerted loading of Mcm2-7 double hexamers around DNA during DNA replication origin licensing. Cell. 2009 Nov 13;139(4):719-30. doi: 10.1016/j.cell.2009.10.015. Epub 2009 Nov, 5. PMID:19896182 doi:http://dx.doi.org/10.1016/j.cell.2009.10.015
- ↑ Evrin C, Clarke P, Zech J, Lurz R, Sun J, Uhle S, Li H, Stillman B, Speck C. A double-hexameric MCM2-7 complex is loaded onto origin DNA during licensing of eukaryotic DNA replication. Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20240-5. doi:, 10.1073/pnas.0911500106. Epub 2009 Nov 12. PMID:19910535 doi:http://dx.doi.org/10.1073/pnas.0911500106
- ↑ Takayama Y, Kamimura Y, Okawa M, Muramatsu S, Sugino A, Araki H. GINS, a novel multiprotein complex required for chromosomal DNA replication in budding yeast. Genes Dev. 2003 May 1;17(9):1153-65. PMID:12730134 doi:http://dx.doi.org/10.1101/gad.1065903
- ↑ Shimizu K, Hashimoto K, Kirchner JM, Nakai W, Nishikawa H, Resnick MA, Sugino A. Fidelity of DNA polymerase epsilon holoenzyme from budding yeast Saccharomyces cerevisiae. J Biol Chem. 2002 Oct 4;277(40):37422-9. Epub 2002 Jul 17. PMID:12124389 doi:http://dx.doi.org/10.1074/jbc.M204476200
- ↑ Remus D, Beuron F, Tolun G, Griffith JD, Morris EP, Diffley JF. Concerted loading of Mcm2-7 double hexamers around DNA during DNA replication origin licensing. Cell. 2009 Nov 13;139(4):719-30. doi: 10.1016/j.cell.2009.10.015. Epub 2009 Nov, 5. PMID:19896182 doi:http://dx.doi.org/10.1016/j.cell.2009.10.015
- ↑ Evrin C, Clarke P, Zech J, Lurz R, Sun J, Uhle S, Li H, Stillman B, Speck C. A double-hexameric MCM2-7 complex is loaded onto origin DNA during licensing of eukaryotic DNA replication. Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20240-5. doi:, 10.1073/pnas.0911500106. Epub 2009 Nov 12. PMID:19910535 doi:http://dx.doi.org/10.1073/pnas.0911500106
- ↑ Goswami P, Abid Ali F, Douglas ME, Locke J, Purkiss A, Janska A, Eickhoff P, Early A, Nans A, Cheung AMC, Diffley JFX, Costa A. Structure of DNA-CMG-Pol epsilon elucidates the roles of the non-catalytic polymerase modules in the eukaryotic replisome. Nat Commun. 2018 Nov 29;9(1):5061. doi: 10.1038/s41467-018-07417-1. PMID:30498216 doi:http://dx.doi.org/10.1038/s41467-018-07417-1
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