Structural analysis of a eukaryotic sliding DNA clamp-clamp loader complex.

Gregory D Bowman; Mike O'Donnell; John Kuriyan

doi:10.1038/nature02585

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PubMed · 15201901

Structural analysis of a eukaryotic sliding DNA clamp-clamp loader complex.

Gregory D Bowman·Mike O'Donnell·John Kuriyan

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Abstract

Sliding clamps are ring-shaped proteins that encircle DNA and confer high processivity on DNA polymerases. Here we report the crystal structure of the five-protein clamp loader complex (replication factor-C, RFC) of the yeast Saccharomyces cerevisiae, bound to the sliding clamp (proliferating cell nuclear antigen, PCNA). Tight interfacial coordination of the ATP analogue ATP-gammaS by RFC results in a spiral arrangement of the ATPase domains of the clamp loader above the PCNA ring. Placement of a model for primed DNA within the central hole of PCNA reveals a striking correspondence between the RFC spiral and the grooves of the DNA double helix. This model, in which the clamp loader complex locks onto primed DNA in a screw-cap-like arrangement, provides a simple explanation for the process by which the engagement of primer-template junctions by the RFC:PCNA complex results in ATP hydrolysis and release of the sliding clamp on DNA.

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Adenosine Triphosphate Binding Sites DNA DNA-Binding Proteins Eukaryotic Cells Models, Molecular Nucleic Acid Conformation Proliferating Cell Nuclear Antigen Protein Conformation Protein Subunits Replication Protein C Saccharomyces cerevisiae Saccharomyces cerevisiae Proteins Journal Article Research Support, U.S. Gov't, P.H.S.

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Gregory D Bowman, Mike O'Donnell, John Kuriyan. 2004-06-17. Structural analysis of a eukaryotic sliding DNA clamp-clamp loader complex.. https://doi.org/10.1038/nature02585

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