9gjp

From Proteopedia

(Difference between revisions)

Current revision

OCCM maturation intermediate stalled with an Arginine Finger mutation in Mcm5: Conformer 2

Structural highlights

9gjp is a 10 chain structure with sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Electron Microscopy, Resolution 3.4Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

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.^[1] ^[2]

Publication Abstract from PubMed

The MCM motor of the eukaryotic replicative helicase is loaded as a double hexamer onto DNA by the Origin Recognition Complex (ORC), Cdc6, and Cdt1. ATP binding supports formation of the ORC-Cdc6-Cdt1-MCM (OCCM) helicase-recruitment complex where ORC-Cdc6 and one MCM hexamer form two juxtaposed rings around duplex DNA. ATP hydrolysis by MCM completes MCM loading but the mechanism is unknown. Here, we used cryo-EM to characterise helicase loading with ATPase-dead Arginine Finger variants of the six MCM subunits. We report the structure of two MCM complexes with different DNA grips, stalled as they mature to loaded MCM. The Mcm2 Arginine Finger-variant stabilises DNA binding by Mcm2 away from ORC/Cdc6. The Arginine Finger-variant of the neighbouring Mcm5 subunit stabilises DNA engagement by Mcm5 downstream of the Mcm2 binding site. Cdc6 and Orc1 progressively disengage from ORC as MCM translocates along DNA. We observe that duplex DNA translocation by MCM involves a set of leading-strand contacts by the pre-sensor 1 ATPase hairpins and lagging-strand contacts by the helix-2-insert hairpins. Mutating any of the MCM residues involved impairs high-salt resistant DNA binding in vitro and double-hexamer formation assessed by electron microscopy. Thus, ATPase-powered duplex DNA translocation away from ORC underlies MCM loading.

Unidirectional MCM translocation away from ORC drives origin licensing.,Butryn A, Greiwe JF, Costa A Nat Commun. 2025 Jan 17;16(1):782. doi: 10.1038/s41467-025-56143-y. PMID:39824870^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

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
↑ Butryn A, Greiwe JF, Costa A. Unidirectional MCM translocation away from ORC drives origin licensing. Nat Commun. 2025 Jan 17;16(1):782. PMID:39824870 doi:10.1038/s41467-025-56143-y

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/9gjp"

Categories: Large Structures | Saccharomyces cerevisiae | Butryn A | Costa A

@@ Line 1: / Line 1: @@
-'''Unreleased structure'''
-The entry 9gjp is ON HOLD  until Paper Publication
+==OCCM maturation intermediate stalled with an Arginine Finger mutation in Mcm5: Conformer 2==
+<StructureSection load='9gjp' size='340' side='right'caption='[[9gjp]], [[Resolution|resolution]] 3.40&Aring;' scene=''>
+== Structural highlights ==
+<table><tr><td colspan='2'>[[9gjp]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9GJP OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9GJP FirstGlance]. <br>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.4&#8491;</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>, <scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=9gjp FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9gjp OCA], [https://pdbe.org/9gjp PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9gjp RCSB], [https://www.ebi.ac.uk/pdbsum/9gjp PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9gjp ProSAT]</span></td></tr>
+</table>
+== Function ==
+[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 ==
+The MCM motor of the eukaryotic replicative helicase is loaded as a double hexamer onto DNA by the Origin Recognition Complex (ORC), Cdc6, and Cdt1. ATP binding supports formation of the ORC-Cdc6-Cdt1-MCM (OCCM) helicase-recruitment complex where ORC-Cdc6 and one MCM hexamer form two juxtaposed rings around duplex DNA. ATP hydrolysis by MCM completes MCM loading but the mechanism is unknown. Here, we used cryo-EM to characterise helicase loading with ATPase-dead Arginine Finger variants of the six MCM subunits. We report the structure of two MCM complexes with different DNA grips, stalled as they mature to loaded MCM. The Mcm2 Arginine Finger-variant stabilises DNA binding by Mcm2 away from ORC/Cdc6. The Arginine Finger-variant of the neighbouring Mcm5 subunit stabilises DNA engagement by Mcm5 downstream of the Mcm2 binding site. Cdc6 and Orc1 progressively disengage from ORC as MCM translocates along DNA. We observe that duplex DNA translocation by MCM involves a set of leading-strand contacts by the pre-sensor 1 ATPase hairpins and lagging-strand contacts by the helix-2-insert hairpins. Mutating any of the MCM residues involved impairs high-salt resistant DNA binding in vitro and double-hexamer formation assessed by electron microscopy. Thus, ATPase-powered duplex DNA translocation away from ORC underlies MCM loading.
-Authors:
+Unidirectional MCM translocation away from ORC drives origin licensing.,Butryn A, Greiwe JF, Costa A Nat Commun. 2025 Jan 17;16(1):782. doi: 10.1038/s41467-025-56143-y. PMID:39824870<ref>PMID:39824870</ref>
-Description:
+From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
-[[Category: Unreleased Structures]]
+</div>
+<div class="pdbe-citations 9gjp" style="background-color:#fffaf0;"></div>
+== References ==
+<references/>
+__TOC__
+</StructureSection>
+[[Category: Large Structures]]
+[[Category: Saccharomyces cerevisiae]]
+[[Category: Butryn A]]
+[[Category: Costa A]]

9gjp

From Proteopedia

Current revision

OCCM maturation intermediate stalled with an Arginine Finger mutation in Mcm5: Conformer 2

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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