ATM-phosphorylated SPOP Contributes to 53BP1 Exclusion from Chromatin During DNA Replication
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53BP1 activates nonhomologous end joining (NHEJ) and inhibits homologous recombination (HR) repair of DNA double-strand breaks (DSBs). Dissociation of 53BP1 from DSBs and consequent activation of HR, a less error-prone pathway than NHEJ, helps maintain genome integrity during DNA replication; however, the underlying mechanisms are not fully understood. Here, we demonstrate that E3 ubiquitin ligase SPOP promotes HR during S phase of the cell cycle by excluding 53BP1 from DSBs. In response to DNA damage, ATM kinase-catalyzed phosphorylation of SPOP causes a conformational change in SPOP, revealed by x-ray crystal structures, that stabilizes its interaction with 53BP1. 53BP1-bound SPOP induces polyubiquitination of 53BP1, eliciting 53BP1 extraction from chromatin by a valosin-containing protein/p97 segregase complex. Our work shows that SPOP facilitates HR repair over NHEJ during DNA replication by contributing to 53BP1 removal from chromatin. Cancer-derived SPOP mutations block SPOP interaction with 53BP1, inducing HR defects and chromosomal instability.
Ye Q, Ma J, Wang Z, Liu T, Wang B, Zhu L Nat Commun. 2024; 15(1):10596.
PMID: 39632881 PMC: 11618752. DOI: 10.1038/s41467-024-54978-5.
53BP1-the 'Pandora's box' of genome integrity.
Kilgas S, Swift M, Chowdhury D DNA Repair (Amst). 2024; 144:103779.
PMID: 39476547 PMC: 11611608. DOI: 10.1016/j.dnarep.2024.103779.
Lim B, Matsui Y, Jung S, Djekidel M, Qi W, Yuan Z PLoS Biol. 2024; 22(9):e3002760.
PMID: 39226322 PMC: 11398655. DOI: 10.1371/journal.pbio.3002760.
Effect of ubiquitin protease system on DNA damage response in prostate cancer (Review).
Lin Y, Jin X Exp Ther Med. 2023; 27(1):33.
PMID: 38125344 PMC: 10731405. DOI: 10.3892/etm.2023.12321.
de la Pena Avalos B, Paquet N, Tropee R, Coulombe Y, Palacios H, Leung J Nucleic Acids Res. 2023; 52(3):1173-1187.
PMID: 38084915 PMC: 10853800. DOI: 10.1093/nar/gkad1177.