The essential elements for the noncovalent association of two DNA ends during NHEJ synapsis.
Nat Commun
; 10(1): 3588, 2019 08 09.
Article
em En
| MEDLINE
| ID: mdl-31399561
ABSTRACT
One of the most central questions about the repair of a double-strand DNA break (DSB) concerns how the two free DNA ends are brought together - a step called synapsis. Using single-molecule FRET (smFRET), we show here that both Ku plus XRCC4DNA ligase IV are necessary and sufficient to achieve a flexible synapsis of blunt DNA ends, whereas either alone is not. Addition of XLF causes a transition to a close synaptic state, and maximum efficiency of close synapsis is achieved within 20 min. The promotion of close synapsis by XLF indicates a role that is independent of a filament structure, with action focused at the very ends of each duplex. DNA-PKcs is not required for the formation of either the flexible or close synaptic states. This model explains in biochemical terms the evolutionarily central synaptic role of Ku, X4L4, and XLF in NHEJ for all eukaryotes.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Quebras de DNA de Cadeia Dupla
/
Reparo do DNA por Junção de Extremidades
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Revista:
Nat Commun
Assunto da revista:
BIOLOGIA
/
CIENCIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Canadá