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bioRxiv · 10.1101/2020.01.24.918474

Crystal Structure of the Tof1-Csm3 (Timeless-Tipin) Fork Protection Complex

Grabarczyk, D. B.
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Abstract

The Tof1-Csm3 fork protection complex has a central role in the replisome - it promotes the progression of DNA replication forks and protects them when they stall, while also enabling cohesion establishment and checkpoint responses. Here, I present the crystal structure of the Tof1-Csm3 complex from Chaetomium thermophilum at 3.1 [A] resolution. The structure reveals that Tof1 is an extended alpha-helical repeat protein which is capped at its C-terminal end by Csm3, a small helical bundle protein. I also characterize the DNA binding properties of the complex and a cancer-associated peptide-binding site. This study provides the molecular basis for understanding the functions of the Tof1-Csm3 complex, its human orthologue the Timeless-Tipin complex and additionally the Drosophila circadian rhythm protein Timeless.

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Grabarczyk, D. B.. 2020-01-24. Crystal Structure of the Tof1-Csm3 (Timeless-Tipin) Fork Protection Complex. https://doi.org/10.1101/2020.01.24.918474

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