Rad54B serves as a scaffold in the DNA damage response that limits checkpoint strength.
Nat Commun
; 5: 5426, 2014 Nov 11.
Article
in En
| MEDLINE
| ID: mdl-25384516
ABSTRACT
The strength of the DNA damage checkpoint critically influences cell fate, yet the mechanisms behind the fine tuning of checkpoint strength during the DNA damage response (DDR) are poorly understood. Here we show that Rad54B--a SNF2 helicase-like DNA-repair protein--limits the strength of both the G1/S and G2/M checkpoints. We find that Rad54B functions as a scaffold for p53 degradation via its direct interaction with the MDM2-MDMX ubiquitin-ligase complex. During the early phases of the DDR, Rad54B is upregulated, thereby maintaining low checkpoint strength and facilitating cell cycle progression. Once the p53-mediated checkpoint is established, Rad54B is downregulated, and high checkpoint strength is maintained. Constitutive upregulation of Rad54B activity, which is frequently observed in tumours, promotes genomic instability because of checkpoint override. Thus, the scaffolding function of Rad54B dynamically regulates the maintenance of genome integrity by limiting checkpoint strength.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
DNA Damage
/
Nuclear Proteins
/
Nuclear Matrix
/
Tumor Suppressor Protein p53
/
DNA Helicases
/
Cell Cycle Checkpoints
Limits:
Humans
Language:
En
Journal:
Nat Commun
Journal subject:
BIOLOGIA
/
CIENCIA
Year:
2014
Document type:
Article
Affiliation country:
Japan
Country of publication:
ENGLAND
/
ESCOCIA
/
GB
/
GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
/
SCOTLAND
/
UK
/
UNITED KINGDOM