Poly(ADP-ribosyl)ation links the chromatin remodeler SMARCA5/SNF2H to RNF168-dependent DNA damage signaling.
J Cell Sci
; 126(Pt 4): 889-903, 2013 Feb 15.
Article
em En
| MEDLINE
| ID: mdl-23264744
ABSTRACT
Ionizing radiation (IR)-induced DNA double-strand breaks (DSBs) arising in native chromatin elicit an RNF8/RNF168-dependent ubiquitylation response, which triggers the recruitment of various repair factors. Precisely how this response is regulated in the context of chromatin remains largely unexplored. Here, we show that SMARCA5/SNF2H, the catalytic subunit of ISWI chromatin remodeling complexes, is recruited to DSBs in a poly(ADP-ribose) polymerase 1 (PARP1)-dependent manner. Remarkably, PARP activity, although dispensable for the efficient spreading of γH2AX into damaged chromatin, selectively promotes spreading of SMARCA5, the E3 ubiquitin ligase RNF168, ubiquitin conjugates and the ubiquitin-binding factors RAD18 and the RAP80-BRCA1 complex throughout DSB-flanking chromatin. This suggests that PARP regulates the spatial organization of the RNF168-driven ubiquitin response to DNA damage. In support of this, we show that SMARCA5 and RNF168 interact in a DNA damage- and PARP-dependent manner. RNF168 became poly(ADP-ribosyl)ated after DNA damage, while RNF168 and poly(ADP-ribose) chains were required for SMARCA5 binding in vivo, explaining how SMARCA5 is linked to the RNF168 ubiquitin cascade. Moreover, SMARCA5 was found to regulate the ubiquitin response by promoting RNF168 accumulation at DSBs, which subsequently facilitates efficient ubiquitin conjugation and BRCA1 assembly. Underlining the importance of these findings, we show that SMARCA5 depletion renders cells sensitive to IR and results in DSB repair defects. Our study unveils a functional link between DNA damage-induced poly(ADP-ribosyl)ation, SMARCA5-mediated chromatin remodeling and RNF168-dependent signaling and repair of DSBs.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Dano ao DNA
/
Proteínas Cromossômicas não Histona
/
Adenosina Trifosfatases
/
Ubiquitina-Proteína Ligases
/
Montagem e Desmontagem da Cromatina
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Cell Sci
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Holanda