|
|
| Line 3: |
Line 3: |
| | <SX load='3ja8' size='340' side='right' viewer='molstar' caption='[[3ja8]], [[Resolution|resolution]] 3.80Å' scene=''> | | <SX load='3ja8' size='340' side='right' viewer='molstar' caption='[[3ja8]], [[Resolution|resolution]] 3.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3ja8]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae_s288c Saccharomyces cerevisiae s288c]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3JA8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3JA8 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3ja8]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae_S288C Saccharomyces cerevisiae S288C]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3JA8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3JA8 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.8Å</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/DNA_helicase DNA helicase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.4.12 3.6.4.12] </span></td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene></td></tr> |
| | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3ja8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ja8 OCA], [https://pdbe.org/3ja8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3ja8 RCSB], [https://www.ebi.ac.uk/pdbsum/3ja8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3ja8 ProSAT]</span></td></tr> | | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3ja8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ja8 OCA], [https://pdbe.org/3ja8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3ja8 RCSB], [https://www.ebi.ac.uk/pdbsum/3ja8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3ja8 ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[https://www.uniprot.org/uniprot/MCM7_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref> [[https://www.uniprot.org/uniprot/MCM5_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref> [[https://www.uniprot.org/uniprot/MCM2_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref> [[https://www.uniprot.org/uniprot/MCM4_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref> [[https://www.uniprot.org/uniprot/MCM3_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref> [[https://www.uniprot.org/uniprot/MCM6_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref>
| + | [https://www.uniprot.org/uniprot/MCM2_YEAST 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.<ref>PMID:19896182</ref> <ref>PMID:19910535</ref> |
| - | <div style="background-color:#fffaf0;">
| + | |
| - | == Publication Abstract from PubMed ==
| + | |
| - | DNA replication in eukaryotes is strictly regulated by several mechanisms. A central step in this replication is the assembly of the heterohexameric minichromosome maintenance (MCM2-7) helicase complex at replication origins during G1 phase as an inactive double hexamer. Here, using cryo-electron microscopy, we report a near-atomic structure of the MCM2-7 double hexamer purified from yeast G1 chromatin. Our structure shows that two single hexamers, arranged in a tilted and twisted fashion through interdigitated amino-terminal domain interactions, form a kinked central channel. Four constricted rings consisting of conserved interior beta-hairpins from the two single hexamers create a narrow passageway that tightly fits duplex DNA. This narrow passageway, reinforced by the offset of the two single hexamers at the double hexamer interface, is flanked by two pairs of gate-forming subunits, MCM2 and MCM5. These unusual features of the twisted and tilted single hexamers suggest a concerted mechanism for the melting of origin DNA that requires structural deformation of the intervening DNA.
| + | |
| - | | + | |
| - | Structure of the eukaryotic MCM complex at 3.8 A.,Li N, Zhai Y, Zhang Y, Li W, Yang M, Lei J, Tye BK, Gao N Nature. 2015 Aug 13;524(7564):186-91. doi: 10.1038/nature14685. Epub 2015 Jul 29. PMID:26222030<ref>PMID:26222030</ref>
| + | |
| - | | + | |
| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
| + | |
| - | </div>
| + | |
| - | <div class="pdbe-citations 3ja8" style="background-color:#fffaf0;"></div>
| + | |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </SX> | | </SX> |
| - | [[Category: DNA helicase]] | |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Saccharomyces cerevisiae s288c]] | + | [[Category: Saccharomyces cerevisiae S288C]] |
| - | [[Category: Gao, N]] | + | [[Category: Gao N]] |
| - | [[Category: Lei, J]] | + | [[Category: Lei J]] |
| - | [[Category: Li, N]] | + | [[Category: Li N]] |
| - | [[Category: Li, W]] | + | [[Category: Li W]] |
| - | [[Category: Tye, B K]] | + | [[Category: Tye BK]] |
| - | [[Category: Yang, M]] | + | [[Category: Yang M]] |
| - | [[Category: Zhai, Y]] | + | [[Category: Zhai Y]] |
| - | [[Category: Zhang, Y]] | + | [[Category: Zhang Y]] |
| - | [[Category: Cryo-em]]
| + | |
| - | [[Category: Dna replication]]
| + | |
| - | [[Category: Hydrolase]]
| + | |
| - | [[Category: Mcm2-7]]
| + | |
| - | [[Category: Single particle]]
| + | |
