EMD-20473

Single-particle
7.0 Å
EMD-20473 Deposition: 16/07/2019
Map released: 20/11/2019
Last modified: 16/10/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-20473

Structure of Ctf4 trimer in complex with three CMG helicases

EMD-20473

Single-particle
7.0 Å
EMD-20473 Deposition: 16/07/2019
Map released: 20/11/2019
Last modified: 16/10/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Saccharomyces cerevisiae
Sample: CMG-CMG-CMG-Ctf4
Fitted models: 6pto (Avg. Q-score: 0.087)

Deposition Authors: Yuan Z , Georgescu R
Ctf4 organizes sister replisomes and Pol alpha into a replication factory.
PUBMED: 31589141
DOI: doi:10.7554/eLife.47405
ISSN: 2050-084X
Abstract:
The current view is that eukaryotic replisomes are independent. Here we show that Ctf4 tightly dimerizes CMG helicase, with an extensive interface involving Psf2, Cdc45, and Sld5. Interestingly, Ctf4 binds only one Pol α-primase. Thus, Ctf4 may have evolved as a trimer to organize two helicases and one Pol α-primase into a replication factory. In the 2CMG-Ctf43-1Pol α-primase factory model, the two CMGs nearly face each other, placing the two lagging strands toward the center and two leading strands out the sides. The single Pol α-primase is centrally located and may prime both sister replisomes. The Ctf4-coupled-sister replisome model is consistent with cellular microscopy studies revealing two sister forks of an origin remain attached and are pushed forward from a protein platform. The replication factory model may facilitate parental nucleosome transfer during replication.