title: A new non-catalytic role for ubiquitin ligase RNF8 in unfolding higher-order chromatin structure.
abstract: The ubiquitin ligases RNF8 and RNF168 orchestrate DNA damage signalling through the ubiquitylation of histone H2A and the recruitment of downstream repair factors. Here, we demonstrate that RNF8, but not RNF168 or the canonical H2A ubiquitin ligase RNF2, mediates extensive chromatin decondensation. Our data show that CHD4, the catalytic subunit of the NuRD complex, interacts with RNF8 and is essential for RNF8-mediated chromatin unfolding. The chromatin remodelling activity of CHD4 promotes efficient ubiquitin conjugation and assembly of RNF168 and BRCA1 at DNA double-strand breaks. Interestingly, RNF8-mediated recruitment of CHD4 and subsequent chromatin remodelling were independent of the ubiquitin-ligase activity of RNF8, but involved a non-canonical interaction with the forkhead-associated (FHA) domain. Our study reveals a new mechanism of chromatin remodelling-assisted ubiquitylation, which involves the cooperation between CHD4 and RNF8 to create a local chromatin environment that is permissive to the assembly of checkpoint and repair machineries at DNA lesions.
authors.affiliation: Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Martijn S
authors.initials: MS
authors.lastname: Luijsterburg
authors.forename: Klara
authors.initials: K
authors.lastname: Acs
authors.forename: Leena
authors.initials: L
authors.lastname: Ackermann
authors.forename: Wouter W
authors.initials: WW
authors.lastname: Wiegant
authors.forename: Simon
authors.initials: S
authors.lastname: Bekker-Jensen
authors.forename: Dorthe H
authors.initials: DH
authors.lastname: Larsen
authors.forename: Kum Kum
authors.initials: KK
authors.lastname: Khanna
authors.forename: Haico
authors.initials: H
authors.lastname: van Attikum
authors.forename: Niels
authors.initials: N
authors.lastname: Mailand
authors.forename: Nico P
authors.initials: NP
authors.lastname: Dantuma
mesh_terms: D000818:Animals; D001324:Autoantigens / Q000378:metabolism; D019313:BRCA1 Protein / Q000378:metabolism; D045744:Cell Line, Tumor; D002843:Chromatin / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D006224:Cricetinae; D053903:DNA Breaks, Double-Stranded; D004265:DNA Helicases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex / Q000378:metabolism; D051379:Mice; D025801:Ubiquitin / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D001324:Autoantigens; D019313:BRCA1 Protein; C115323:CHD4 protein, human; D002843:Chromatin; D004268:DNA-Binding Proteins; C486521:RNF8 protein, human; D025801:Ubiquitin; C535210:RNF168 protein, human; C549817:Rnf8 protein, mouse; D044767:Ubiquitin-Protein Ligases; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex; C509277:Mi-2beta protein, mouse; D004265:DNA Helicases