A role for the spindle assembly checkpoint in the DNA damage response

Spontaneous DNA damage poses a continuous threat to genomic integrity. If unchecked, genotoxic insults result in genomic instability, a hallmark of cancer cells. In eukaryotic cells a DNA Damage Response (DDR) detects and responds to genotoxic stress, acting as an anti-cancer barrier in humans. Amon...

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Detalles Bibliográficos
Autores: Palou, Roger|||0000-0001-7674-9358, Palou Marin, Gloria|||0000-0002-1077-4275, Garcia Quintana, David|||0000-0002-4909-6686
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:185943
Acceso en línea:https://ddd.uab.cat/record/185943
https://dx.doi.org/urn:doi:10.1007/s00294-016-0634-y
Access Level:acceso abierto
Palabra clave:DNA damage response (DDR)
Spindle assembly checkpoint (SAC)
S Phase checkpoint
Chromosome segregation
Genomic instability
Cyclin Dependent Kinase (Cdk1)
Descripción
Sumario:Spontaneous DNA damage poses a continuous threat to genomic integrity. If unchecked, genotoxic insults result in genomic instability, a hallmark of cancer cells. In eukaryotic cells a DNA Damage Response (DDR) detects and responds to genotoxic stress, acting as an anti-cancer barrier in humans. Among other actions, the DDR blocks the segregation of incompletely replicated or damaged chromosomes, thus preventing aneuploidy. In a work aimed at better understanding such S-M control, we recently showed that cells block anaphase through different control pathways. The S phase checkpoint kinase Mec1/ATR inhibits mitotic Cyclin Dependent Kinase activity through effector kinases Swe1/Wee1 and Rad53/Chk2. Cells also stabilize the levels of Pds1/securin to block sister chromatid segregation in response to DNA damage. We show here that Pds1/securin abundance is still secured when the S phase checkpoint response is fully abrogated in mec1/ATR tel1/ATM double null mutants. When such cells are exposed to genotoxic stress, Pds1/securin is stabilized in a spindle assembly checkpoint (SAC) dependent manner. Disruption of the SAC and the S phase checkpoint together, allows chromosome segregation in the presence of DNA damage or replication stress. Our results place the SAC as a part of the DDR, which appears to count on different, independent control layers to preserve genomic integrity when chromosome replication is challenged.