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Autophosphorylation of DNA-PK(CS) regulates its dynamics at DNA double-strand breaks
The DNA-dependent protein kinase catalytic subunit (DNA-PK(CS)) plays an important role during the repair of DNA double-strand breaks (DSBs). It is recruited to DNA ends in the early stages of the nonhomologous end-joining (NHEJ) process, which mediates DSB repair. To study DNA-PK(CS) recruitment in...
Autores principales: | , , , , , , , , , |
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Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
2007
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2064131/ https://www.ncbi.nlm.nih.gov/pubmed/17438073 http://dx.doi.org/10.1083/jcb.200608077 |
Sumario: | The DNA-dependent protein kinase catalytic subunit (DNA-PK(CS)) plays an important role during the repair of DNA double-strand breaks (DSBs). It is recruited to DNA ends in the early stages of the nonhomologous end-joining (NHEJ) process, which mediates DSB repair. To study DNA-PK(CS) recruitment in vivo, we used a laser system to introduce DSBs in a specified region of the cell nucleus. We show that DNA-PK(CS) accumulates at DSB sites in a Ku80-dependent manner, and that neither the kinase activity nor the phosphorylation status of DNA-PK(CS) influences its initial accumulation. However, impairment of both of these functions results in deficient DSB repair and the maintained presence of DNA-PK(CS) at unrepaired DSBs. The use of photobleaching techniques allowed us to determine that the kinase activity and phosphorylation status of DNA-PK(CS) influence the stability of its binding to DNA ends. We suggest a model in which DNA-PK(CS) phosphorylation/autophosphorylation facilitates NHEJ by destabilizing the interaction of DNA-PK(CS) with the DNA ends. |
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