EMD-41664

Single-particle
4.1 Å
EMD-41664 Deposition: 20/08/2023
Map released: 04/09/2024
Last modified: 09/10/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-41664

Cryo-EM structure of S. cerevisiae Ctf18-RFC-PCNA-PolE-DNA complex

EMD-41664

Single-particle
4.1 Å
EMD-41664 Deposition: 20/08/2023
Map released: 04/09/2024
Last modified: 09/10/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Saccharomyces cerevisiae, synthetic construct
Sample: Ctf18-RFC-PCNA-PolE-DNA complex
Fitted models: 8twa (Avg. Q-score: 0.349)

Deposition Authors: Yuan Z , Georgescu R , O'Donnell M, Li H
Mechanism of PCNA loading by Ctf18-RFC for leading-strand DNA synthesis.
Yuan Z , Georgescu R , Yao NY , Yurieva O , O'Donnell ME , Li H
(2024) Science , 385 , eadk5901 - eadk5901
PUBMED: 39088616
DOI: doi:10.1126/science.adk5901
ISSN: 1095-9203
ASTM: SCIEAS
Abstract:
The proliferating cell nuclear antigen (PCNA) clamp encircles DNA to hold DNA polymerases (Pols) to DNA for processivity. The Ctf18-RFC PCNA loader, a replication factor C (RFC) variant, is specific to the leading-strand Pol (Polε). We reveal here the underlying mechanism of Ctf18-RFC specificity to Polε using cryo-electron microscopy and biochemical studies. We found that both Ctf18-RFC and Polε contain specific structural features that direct PCNA loading onto DNA. Unlike other clamp loaders, Ctf18-RFC has a disordered ATPase associated with a diverse cellular activities (AAA+) motor that requires Polε to bind and stabilize it for efficient PCNA loading. In addition, Ctf18-RFC can pry prebound Polε off of DNA, then load PCNA onto DNA and transfer the PCNA-DNA back to Polε. These elements in both Ctf18-RFC and Polε provide specificity in loading PCNA onto DNA for Polε.