PT - JOURNAL ARTICLE AU - Zuanning Yuan AU - Roxana Georgescu AU - Ruda de Luna Almeida Santos AU - Daniel Zhang AU - Lin Bai AU - Nina Y. Yao AU - Gongpu Zhao AU - Michael E. O’Donnell AU - Huilin Li TI - Ctf4 organizes sister replisomes and Pol α into a replication factory AID - 10.1101/735746 DP - 2019 Jan 01 TA - bioRxiv PG - 735746 4099 - http://biorxiv.org/content/early/2019/08/23/735746.short 4100 - http://biorxiv.org/content/early/2019/08/23/735746.full AB - 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.