RRC ID 81954
Author Kim S, Park SH, Kang N, Ra JS, Myung K, Lee KY.
Title Polyubiquitinated PCNA triggers SLX4-mediated break-induced replication in alternative lengthening of telomeres (ALT) cancer cells.
Journal Nucleic Acids Res
Abstract Replication stresses are the major source of break-induced replication (BIR). Here, we show that in alternative lengthening of telomeres (ALT) cells, replication stress-induced polyubiquitinated proliferating cell nuclear antigen (PCNA) (polyUb-PCNA) triggers BIR at telomeres and the common fragile site (CFS). Consistently, depleting RAD18, a PCNA ubiquitinating enzyme, reduces the occurrence of ALT-associated promyelocytic leukemia (PML) bodies (APBs) and mitotic DNA synthesis at telomeres and CFS, both of which are mediated by BIR. In contrast, inhibiting ubiquitin-specific protease 1 (USP1), an Ub-PCNA deubiquitinating enzyme, results in an increase in the above phenotypes in a RAD18- and UBE2N (the PCNA polyubiquitinating enzyme)-dependent manner. Furthermore, deficiency of ATAD5, which facilitates USP1 activity and unloads PCNAs, augments recombination-associated phenotypes. Mechanistically, telomeric polyUb-PCNA accumulates SLX4, a nuclease scaffold, at telomeres through its ubiquitin-binding domain and increases telomere damage. Consistently, APB increase induced by Ub-PCNA depends on SLX4 and structure-specific endonucleases. Taken together, our results identified the polyUb-PCNA-SLX4 axis as a trigger for directing BIR.
Volume 52(19)
Pages 11785-11805
Published 2024-10-28
DOI 10.1093/nar/gkae785
PII 7759988
PMID 39291733
PMC PMC11514459
MeSH ATPases Associated with Diverse Cellular Activities* / genetics ATPases Associated with Diverse Cellular Activities* / metabolism Cell Line, Tumor DNA Replication* DNA-Binding Proteins* / genetics DNA-Binding Proteins* / metabolism Humans Phosphoric Diester Hydrolases* / genetics Phosphoric Diester Hydrolases* / metabolism Polyubiquitin / genetics Polyubiquitin / metabolism Proliferating Cell Nuclear Antigen* / genetics Proliferating Cell Nuclear Antigen* / metabolism Recombinases Telomere* / genetics Telomere* / metabolism Telomere Homeostasis* / genetics Ubiquitin-Conjugating Enzymes / genetics Ubiquitin-Conjugating Enzymes / metabolism Ubiquitin-Protein Ligases* / genetics Ubiquitin-Protein Ligases* / metabolism Ubiquitin-Specific Proteases / genetics Ubiquitin-Specific Proteases / metabolism Ubiquitination*
Resource
DNA material CSII-CMV-MCS-IRES2-Bsd (RDB04385)