Persistent DNA damage signaling and DNA polymerase theta promote broken chromosome segregation.

Autor: Clay DE; Department of Cell Biology, Duke University School of Medicine, Durham, NC., Bretscher HS; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC., Jezuit EA; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC., Bush KB; University Program in Genetics and Genomics, Duke University School of Medicine, Durham, NC., Fox DT; Department of Cell Biology, Duke University School of Medicine, Durham, NC.; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC.; University Program in Genetics and Genomics, Duke University School of Medicine, Durham, NC.
Jazyk: angličtina
Zdroj: The Journal of cell biology [J Cell Biol] 2021 Dec 06; Vol. 220 (12). Date of Electronic Publication: 2021 Oct 06.
DOI: 10.1083/jcb.202106116
Abstrakt: Cycling cells must respond to DNA double-strand breaks (DSBs) to avoid genome instability. Missegregation of chromosomes with DSBs during mitosis results in micronuclei, aberrant structures linked to disease. How cells respond to DSBs during mitosis is incompletely understood. We previously showed that Drosophilamelanogaster papillar cells lack DSB checkpoints (as observed in many cancer cells). Here, we show that papillar cells still recruit early acting repair machinery (Mre11 and RPA3) and the Fanconi anemia (FA) protein Fancd2 to DSBs. These proteins persist as foci on DSBs as cells enter mitosis. Repair foci are resolved in a stepwise manner during mitosis. DSB repair kinetics depends on both monoubiquitination of Fancd2 and the alternative end-joining protein DNA polymerase θ. Disruption of either or both of these factors causes micronuclei after DNA damage, which disrupts intestinal organogenesis. This study reveals a mechanism for how cells with inactive DSB checkpoints can respond to DNA damage that persists into mitosis.
(© 2021 Clay et al.)
Databáze: MEDLINE