Biphasic recruitment of TRF2 to DNA damage sites promotes non-sister chromatid homologous recombination repair.
J Cell Sci
; 131(23)2018 12 05.
Article
em En
| MEDLINE
| ID: mdl-30404833
ABSTRACT
TRF2 (TERF2) binds to telomeric repeats and is critical for telomere integrity. Evidence suggests that it also localizes to non-telomeric DNA damage sites. However, this recruitment appears to be precarious and functionally controversial. We find that TRF2 recruitment to damage sites occurs by a two-step mechanism the initial rapid recruitment (phase I), and stable and prolonged association with damage sites (phase II). Phase I is poly(ADP-ribose) polymerase (PARP)-dependent and requires the N-terminal basic domain. The phase II recruitment requires the C-terminal MYB/SANT domain and the iDDR region in the hinge domain, which is mediated by the MRE11 complex and is stimulated by TERT. PARP-dependent recruitment of intrinsically disordered proteins contributes to transient displacement of TRF2 that separates two phases. TRF2 binds to I-PpoI-induced DNA double-strand break sites, which is enhanced by the presence of complex damage and is dependent on PARP and the MRE11 complex. TRF2 depletion affects non-sister chromatid homologous recombination repair, but not homologous recombination between sister chromatids or non-homologous end-joining pathways. Our results demonstrate a unique recruitment mechanism and function of TRF2 at non-telomeric DNA damage sites.
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Base de dados:
MEDLINE
Assunto principal:
Dano ao DNA
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Cromátides
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Proteína 2 de Ligação a Repetições Teloméricas
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Reparo de DNA por Recombinação
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article