Polyubiquitinated PCNA recruits the ZRANB3 translocase to maintain genomic integrity after replication stress.

Publication Year
2012

Type

Journal Article
Abstract

Completion of DNA replication after replication stress depends on PCNA, which undergoes monoubiquitination to stimulate direct bypass of DNA lesions by specialized DNA polymerases or is polyubiquitinated to promote recombination-dependent DNA synthesis across DNA lesions by template switching mechanisms. Here we report that the ZRANB3 translocase, a SNF2 family member related to the SIOD disorder SMARCAL1 protein, is recruited by polyubiquitinated PCNA to promote fork restart following replication arrest. ZRANB3 depletion in mammalian cells results in an increased frequency of sister chromatid exchange and DNA damage sensitivity after treatment with agents that cause replication stress. Using in vitro biochemical assays, we show that recombinant ZRANB3 remodels DNA structures mimicking stalled replication forks and disassembles recombination intermediates. We therefore propose that ZRANB3 maintains genomic stability at stalled or collapsed replication forks by facilitating fork restart and limiting inappropriate recombination that could occur during template switching events.

Journal
Mol Cell
Volume
47
Issue
3
Pages
396-409
Date Published
2012 Aug 10
ISSN Number
1097-4164
Alternate Journal
Mol Cell
PMCID
PMC3613862
PMID
22704558