title: USP45 deubiquitylase controls ERCC1-XPF endonuclease-mediated DNA damage responses.
abstract: Reversible protein ubiquitylation plays important roles in various processes including DNA repair. Here, we identify the deubiquitylase USP45 as a critical DNA repair regulator. USP45 associates with ERCC1, a subunit of the DNA repair endonuclease XPF-ERCC1, via a short acidic motif outside of the USP45 catalytic domain. Wild-type USP45, but not a USP45 mutant defective in ERCC1 binding, efficiently deubiquitylates ERCC1 in vitro, and the levels of ubiquitylated ERCC1 are markedly enhanced in USP45 knockout cells. Cells lacking USP45 are hypersensitive specifically to UV irradiation and DNA interstrand cross-links, similar to cells lacking ERCC1. Furthermore, the repair of UV-induced DNA damage is markedly reduced in USP45-deficient cells. ERCC1 translocation to DNA damage-induced subnuclear foci is markedly impaired in USP45 knockout cells, possibly accounting for defective DNA repair. Finally, USP45 localises to sites of DNA damage in a manner dependent on its deubiquitylase activity, but independent of its ability to bind ERCC1-XPF. Together, these results establish USP45 as a new regulator of XPF-ERCC1 crucial for efficient DNA repair.
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK a.b.perezoliva@dundee.ac.uk j.rouse@dundee.ac.uk d.r.alessi@dundee.ac.uk.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Perez-Oliva
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK.
authors.forename: Christophe
authors.initials: C
authors.lastname: Lachaud
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK.
authors.forename: Piotr
authors.initials: P
authors.lastname: Szyniarowski
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK.
authors.forename: Ivan
authors.initials: I
authors.lastname: Muñoz
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Macartney
authors.affiliation: Janssen Research & Development, LLC, Spring House, PA, USA.
authors.forename: Ian
authors.initials: I
authors.lastname: Hickson
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK a.b.perezoliva@dundee.ac.uk j.rouse@dundee.ac.uk d.r.alessi@dundee.ac.uk.
authors.forename: John
authors.initials: J
authors.lastname: Rouse
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK a.b.perezoliva@dundee.ac.uk j.rouse@dundee.ac.uk d.r.alessi@dundee.ac.uk.
authors.forename: Dario R
authors.initials: DR
authors.lastname: Alessi
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000528:radiation effects; D000818:Animals; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D004249:DNA Damage; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004720:Endonucleases / Q000235:genetics / Q000378:metabolism*; D010450:Endopeptidases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D054875:Ubiquitination; D014466:Ultraviolet Rays / Q000009:adverse effects
chemical_list: D004268:DNA-Binding Proteins; C095888:xeroderma pigmentosum group F protein; C071447:ERCC1 protein, human; D004720:Endonucleases; C499360:Ercc1 protein, mouse; D010450:Endopeptidases
keywords: UV irradiation; interstrand cross‐link; nucleotide excision repair; ubiquitin