Substrate-selective repair and restart of replication forks by DNA translocases

Stalled replication forks are sources of genetic instability. Multiple fork-remodeling enzymes are recruited to stalled forks, but how they work to promote fork restart is poorly understood. By combining ensemble biochemical assays and single-molecule studies with magnetic tweezers, we show that SMA...

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Detalhes bibliográficos
Autores: Bétous, Rémy, Couch, Frank B., Mason, Aaron C., Eichman, Brandt F., Mañosas Castejón, María, Cortez, David
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:España
Recursos:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/53283
Acesso em linha:https://hdl.handle.net/2445/53283
Access Level:acceso abierto
Palavra-chave:ADN
Proteïnes
Cèl·lules canceroses
Escheríchia coli
Reparació de l'ADN
DNA
Proteins
Cancer cells
Escherichia coli
DNA repair
Descrição
Resumo:Stalled replication forks are sources of genetic instability. Multiple fork-remodeling enzymes are recruited to stalled forks, but how they work to promote fork restart is poorly understood. By combining ensemble biochemical assays and single-molecule studies with magnetic tweezers, we show that SMARCAL1 branch migration and DNA-annealing activities are directed by the single-stranded DNA-binding protein RPA to selectively regress stalled replication forks caused by blockage to the leading-strand polymerase and to restore normal replication forks with a lagging-strand gap. We unveil the molecular mechanisms by which RPA enforces SMARCAL1 substrate preference. E. coli RecG acts similarly to SMARCAL1 in the presence of E. coli SSB, whereas the highly related human protein ZRANB3 has different substrate preferences. Our findings identify the important substrates of SMARCAL1 in fork repair, suggest that RecG and SMARCAL1 are functional orthologs, and provide a comprehensive model of fork repair by these DNA translocases.