The DNA damage response acts as a safeguardagainst harmful DNA–RNA hybrids ofdifferent origins

Despite playing physiological roles in specific situations, DNA–RNA hybrids threat genome integrity. To investigate how cells do counteract spontaneous DNA–RNA hybrids, here we screen an siRNA library covering 240 human DNA damage response (DDR) genes and select siRNAs causing DNA–RNA hybrid accumul...

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Detalhes bibliográficos
Autores: Barroso Ceballos, Sonia Inés, Herrera Moyano, Emilia, Muñoz Sánchez, Sergio, García Rubio, María Luisa, Gómez González, Belén, Aguilera López, Andrés
Tipo de documento: artigo
Estado:Versión aceptada para publicación
Data de publicação:2019
País:España
Recursos:Universidad de Sevilla (US)
Repositório:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/93263
Acesso em linha:https://hdl.handle.net/11441/93263
https://doi.org/10.15252/embr.201847250
Access Level:Acceso aberto
Palavra-chave:ATM
ATR
DNA damage response
post-replicative repair
R loop
Descrição
Resumo:Despite playing physiological roles in specific situations, DNA–RNA hybrids threat genome integrity. To investigate how cells do counteract spontaneous DNA–RNA hybrids, here we screen an siRNA library covering 240 human DNA damage response (DDR) genes and select siRNAs causing DNA–RNA hybrid accumulation and a significant increase in hybrid‐dependent DNA breakage. We identify post‐replicative repair and DNA damage checkpoint factors, including those of the ATM/CHK2 and ATR/CHK1 pathways. Thus, spontaneous DNA–RNA hybrids are likely a major source of replication stress, but they can also accumulate and menace genome integrity as a consequence of unrepaired DSBs and post‐replicative ssDNA gaps in normal cells. We show that DNA–RNA hybrid accumulation correlates with increased DNA damage and chromatin compaction marks. Our results suggest that different mechanisms can lead to DNA–RNA hybrids with distinct consequences for replication and DNA dynamics at each cell cycle stage and support the conclusion that DNA–RNA hybrids are a common source of spontaneous DNA damage that remains unsolved under a deficient DDR.