BRCA2 promotes DNA-RNA hybrid resolution by DDX5 helicase at DNA breaks to facilitate their repair

The BRCA2 tumor suppressor is a DNA double-strand break (DSB) repair factor essential for maintaining genome integrity. BRCA2-deficient cells spontaneously accumulate DNA-RNA hybrids, a known source of genome instability. However, the specific role of BRCA2 on these structures remains poorly underst...

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Detalles Bibliográficos
Autores: Sessa, Gaetana, Gómez González, Belén, Silva, Sonia, Pérez Calero, Carmen, Beaurepere, Romane, Barroso Ceballos, Sonia Inés, Martineau, Sylvain, Martin, Charlotte A., Ehlén, Åsa, Martínez, Juan S., Lombard, Bérangére, Loew, Damarys, Vagner, Stéphan, Aguilera López, Andrés, Carreira, Aura
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/110909
Acceso en línea:https://hdl.handle.net/11441/110909
https://doi.org/10.15252/embj.2020106018
Access Level:acceso abierto
Palabra clave:BRCA2
DNA double-strand breaks
DNA-RNA hybrids
Homologous recombination
R-loops
Descripción
Sumario:The BRCA2 tumor suppressor is a DNA double-strand break (DSB) repair factor essential for maintaining genome integrity. BRCA2-deficient cells spontaneously accumulate DNA-RNA hybrids, a known source of genome instability. However, the specific role of BRCA2 on these structures remains poorly understood. Here we identified the DEAD-box RNA helicase DDX5 as a BRCA2-interacting protein. DDX5 associates with DNA-RNA hybrids that form in the vicinity of DSBs, and this association is enhanced by BRCA2. Notably, BRCA2 stimulates the DNA-RNA hybrid-unwinding activity of DDX5 helicase. An impaired BRCA2-DDX5 interaction, as observed in cells expressing the breast cancer variant BRCA2-T207A, reduces the association of DDX5 with DNA-RNA hybrids, decreases the number of RPA foci, and alters the kinetics of appearance of RAD51 foci upon irradiation. Our findings are consistent with DNA-RNA hybrids constituting an impediment for the repair of DSBs by homologous recombination and reveal BRCA2 and DDX5 as active players in their removal.