Journal Article

53BP1 and BRCA1 control pathway choice for stalled replication restart

Xu, Yixi, Ning, Shaokai, Wei, Zheng, Xu, Xinlin, Xu, Ran, Xing, Mengtan, Guo, Rong, Xu, Dongyi

2017

Overview

The cellular pathways that restart stalled replication forks are essential for genome stability and tumor prevention. However, how many of these pathways exist in cells and how these pathways are selectively activated remain unclear. Here, we describe two major fork restart pathways, and demonstrate that their selection is governed by 53BP1 and BRCA1, which are known to control the pathway choice to repair double-strand DNA breaks (DSBs). Specifically, 53BP1 promotes a fork cleavage-free pathway, whereas BRCA1 facilitates a break-induced replication (BIR) pathway coupled with SLX-MUS complex-mediated fork cleavage. The defect in the first pathway, but not DSB repair, in a 53BP1 mutant is largely corrected by disrupting BRCA1, and vice versa. Moreover, PLK1 temporally regulates the switch of these two pathways through enhancing the assembly of the SLX-MUS complex. Our results reveal two distinct fork restart pathways, which are antagonistically controlled by 53BP1 and BRCA1 in a DSB repair-independent manner.

• Publisher: eLife Sciences Publications Ltd,eLife Sciences Publications, Ltd
• Subject: 53BP1 / BRCA1 / BRCA1 protein / BRCA1 Protein - metabolism / Cancer Biology / Cell Line / Chromosomes and Gene Expression / Deoxyribonucleic acid / DNA / DNA Breaks, Double-Stranded / DNA damage / DNA Repair / DNA Replication / Experiments / Genomes / Humans / Medical research / MUS81 / Polo-like kinase 1 / Replication forks / replication stress / RIF1 / stalled replication fork restart / Tumor Suppressor p53-Binding Protein 1 - metabolism