View source for 7tfk


==Atomic model of S. cerevisiae clamp loader RFC bound to two DNA molecules, one at the 5'-recessed end and the other at the 3'-recessed end==
<StructureSection load='7tfk' size='340' side='right'caption='[[7tfk]], [[Resolution|resolution]] 3.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7tfk]] is a 9 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7TFK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7TFK 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]] 3.25&#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=AGS:PHOSPHOTHIOPHOSPHORIC+ACID-ADENYLATE+ESTER'>AGS</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=7tfk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7tfk OCA], [https://pdbe.org/7tfk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7tfk RCSB], [https://www.ebi.ac.uk/pdbsum/7tfk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7tfk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RFC1_YEAST RFC1_YEAST] Component of the ATP-dependent clamp loader RFC complex for the POL30/PCNA homotrimer DNA clamp. During a clamp loading circle, the RFC:clamp complex binds to DNA and the recognition of the double-stranded/single-stranded junction stimulates ATP hydrolysis by RFC. The complex presumably provides bipartite ATP sites in which one subunit supplies a catalytic site for hydrolysis of ATP bound to the neighboring subunit. Dissociation of RFC from the clamp leaves the clamp encircling DNA. Replication factor C (RFC or activator 1) complex acts during elongation of primed DNA templates by DNA polymerase delta and epsilon. RFC has an essential but redundant activity in sister chromatid cohesion establishment.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
RFC uses ATP to assemble PCNA onto primed sites for replicative DNA polymerases delta and epsilon. The RFC pentamer forms a central chamber that binds 3' ss/ds DNA junctions to load PCNA onto DNA during replication. We show here five structures that identify a second DNA binding site in RFC that binds a 5' duplex. This 5' DNA site is located between the N-terminal BRCT domain and AAA+ module of the large Rfc1 subunit. Our structures reveal ideal binding to a 7-nt gap, which includes 2 bp unwound by the clamp loader. Biochemical studies show enhanced binding to 5 and 10 nt gaps, consistent with the structural results. Because both 3' and 5' ends are present at a ssDNA gap, we propose that the 5' site facilitates RFC's PCNA loading activity at a DNA damage-induced gap to recruit gap-filling polymerases. These findings are consistent with genetic studies showing that base excision repair of gaps greater than 1 base requires PCNA and involves the 5' DNA binding domain of Rfc1. We further observe that a 5' end facilitates PCNA loading at an RPA coated 30-nt gap, suggesting a potential role of the RFC 5'-DNA site in lagging strand DNA synthesis.

Cryo-EM structures reveal that RFC recognizes both the 3'- and 5'-DNA ends to load PCNA onto gaps for DNA repair.,Zheng F, Georgescu R, Yao NY, Li H, O'Donnell ME Elife. 2022 Jul 13;11:e77469. doi: 10.7554/eLife.77469. PMID:35829698<ref>PMID:35829698</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7tfk" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Synthetic construct]]
[[Category: Georgescu R]]
[[Category: Li H]]
[[Category: O'Donnell ME]]
[[Category: Yao YN]]
[[Category: Zheng F]]