Fugger, Kasper6; Chu, Wai Kit7; Haahr, Peter5; Kousholt, Arne Nedergaard6; Beck, Halfdan6; Payne, Miranda J5; Hanada, Katsuhiro5; Hickson, Ian D7; Sørensen, Claus Storgaard6
1 Sørensen Group, BRIC Research Groups, BRIC, Københavns Universitet2 Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, Københavns Universitet3 Section I. Center for Healthy Aging, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, Københavns Universitet4 Molecular Aging Program, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, Københavns Universitet5 unknown6 Sørensen Group, BRIC Research Groups, BRIC, Københavns Universitet7 Section I. Center for Healthy Aging, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, Københavns Universitet
The molecular events occurring following the disruption of DNA replication forks are poorly characterized, despite extensive use of replication inhibitors such as hydroxyurea in the treatment of malignancies. Here, we identify a key role for the FBH1 helicase in mediating DNA double-strand break formation following replication inhibition. We show that FBH1-deficient cells are resistant to killing by hydroxyurea, and exhibit impaired activation of the pro-apoptotic factor p53, consistent with decreased DNA double-strand break formation. Similar findings were obtained in murine ES cells carrying disrupted alleles of Fbh1. We also show that FBH1 through its helicase activity co-operates with the MUS81 nuclease in promoting the endonucleolytic DNA cleavage following prolonged replication stress. Accordingly, MUS81 and EME1-depleted cells show increased resistance to the cytotoxic effects of replication stress. Our data suggest that FBH1 helicase activity is required to eliminate cells with excessive replication stress through the generation of MUS81-induced DNA double-strand breaks.
Nature Communications, 2013, Vol 4
Alleles; Animals; Blotting, Southern; Cell Death; Cell Line, Tumor; DNA Breaks, Double-Stranded; DNA Helicases; DNA Replication; DNA-Binding Proteins; Doxycycline; Embryonic Stem Cells; Endonucleases; F-Box Proteins; Humans; Mice; RNA, Small Interfering; Signal Transduction; Stress, Physiological