title: Human RNF169 is a negative regulator of the ubiquitin-dependent response to DNA double-strand breaks.
abstract: Nonproteolytic ubiquitylation of chromatin surrounding deoxyribonucleic acid double-strand breaks (DSBs), mediated by the RNF8/RNF168 ubiquitin ligases, plays a key role in recruiting repair factors, including 53BP1 and BRCA1, to reestablish genome integrity. In this paper, we show that human RNF169, an uncharacterized E3 ubiquitin ligase paralogous to RNF168, accumulated in DSB repair foci through recognition of RNF168-catalyzed ubiquitylation products by its motif interacting with ubiquitin domain. Unexpectedly, RNF169 was dispensable for chromatin ubiquitylation and ubiquitin-dependent accumulation of repair factors at DSB sites. Instead, RNF169 functionally competed with 53BP1 and RAP80-BRCA1 for association with RNF168-modified chromatin independent of its catalytic activity, limiting the magnitude of their recruitment to DSB sites. By delaying accumulation of 53BP1 and RAP80 at damaged chromatin, RNF169 stimulated homologous recombination and restrained nonhomologous end joining, affecting cell survival after DSB infliction. Our results show that RNF169 functions in a noncanonical fashion to harness RNF168-mediated protein recruitment to DSB-containing chromatin, thereby contributing to regulation of DSB repair pathway utilization.
authors.affiliation: Ubiquitin Signaling Group, Department of Disease Biology, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, DK-2200 Copenhagen, Denmark.
authors.forename: Maria
authors.initials: M
authors.lastname: Poulsen
authors.forename: Claudia
authors.initials: C
authors.lastname: Lukas
authors.forename: Jiri
authors.initials: J
authors.lastname: Lukas
authors.forename: Simon
authors.initials: S
authors.lastname: Bekker-Jensen
authors.forename: Niels
authors.initials: N
authors.lastname: Mailand
mesh_terms: D019313:BRCA1 Protein / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000235:genetics; D002843:Chromatin / Q000378:metabolism*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded; D059766:DNA End-Joining Repair; D004268:DNA-Binding Proteins / Q000235:genetics; D057809:HEK293 Cells; D006367:HeLa Cells; D056488:Histone Chaperones; D059765:Homologous Recombination; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering; D000071857:Tumor Suppressor p53-Binding Protein 1; D025801:Ubiquitin / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination; D016335:Zinc Fingers / Q000235:genetics
chemical_list: D019313:BRCA1 Protein; C492913:BRCA1 protein, human; D002352:Carrier Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D056488:Histone Chaperones; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; C486521:RNF8 protein, human; C498301:TP53BP1 protein, human; D000071857:Tumor Suppressor p53-Binding Protein 1; C466234:UIMC1 protein, human; D025801:Ubiquitin; D004247:DNA; C535210:RNF168 protein, human; C572547:RNF169 protein, human; D044767:Ubiquitin-Protein Ligases