PCNA-binding activity separates RNF168 functions in DNA replication and DNA double-stranded break signaling
RNF168 orchestrates a ubiquitin-dependent DNA damage response to regulate the recruitment of repair factors, such as 53BP1 to DNA double-strand breaks (DSBs). In addition to its canonical functions in DSB signaling, RNF168 may facilitate DNA replication fork progression. However, the precise role of RNF168 in DNA replication remains unclear. Here, we demonstrate that RNF168 is recruited to DNA replication factories in a manner that is independent of the canonical DSB response pathway regulated by Ataxia-Telangiectasia Mutated (ATM) and RNF8. We identify a degenerate Proliferating Cell Nuclear Antigen (PCNA)-interacting peptide (DPIP) motif in the C-terminus of RNF168, which together with its Motif Interacting with Ubiquitin (MIU) domain mediates binding to mono-ubiquitylated PCNA at replication factories. An RNF168 mutant harboring inactivating substitutions in its DPIP box and MIU1 domain (termed RNF168 ΔDPIP/ΔMIU1) is not recruited to sites of DNA synthesis and fails to support ongoing DNA replication. Notably, the PCNA interaction-deficient RNF168 ΔDPIP/ΔMIU1 mutant fully rescues the ability of RNF168-/- cells to form 53BP1 foci in response to DNA DSBs. Therefore, RNF168 functions in DNA replication and DSB signaling are fully separable. Our results define a new mechanism by which RNF168 promotes DNA replication independently of its canonical functions in DSB signaling.
Authors
- Pei Zhou (ORCID: https://orcid.org/0000-0002-7823-3416)
- Jay Ramanlal Anand (ORCID: https://orcid.org/0000-0003-2071-9891)
- Kenneth H. Pearce (ORCID: https://orcid.org/0000-0001-8138-5421)
- Satpal S. Jhujh (ORCID: https://orcid.org/0000-0001-5766-659X)
- Elizabeth Mutter‐Rottmayer
- Cyrus Vaziri (ORCID: https://orcid.org/0000-0002-3081-8685)
- Amélie Fradet‐Turcotte (ORCID: https://orcid.org/0000-0002-5431-8650)
- Grant S. Stewart (ORCID: https://orcid.org/0000-0002-0960-3241)
- Steve Chen
- John J. Reynolds (ORCID: https://orcid.org/0000-0001-8690-5828)
- Pablo Ariel (ORCID: https://orcid.org/0000-0002-8494-0379)
- Nandana Nandakumar
- Yang Yang (ORCID: https://orcid.org/0000-0002-5936-4090)
- Xing Cheng (ORCID: https://orcid.org/0000-0002-2389-2377)
- Jing An (ORCID: https://orcid.org/0000-0002-1265-2474)
- Sophie-Anne Blanchet
- Deepika Jayaprakash
- Yanzhe Gao
Institutions
- University of North Carolina at Chapel Hill (US)
- Harbin Medical University (CN)
- Chongqing University (CN)
- Duke University (US)
- Cancer Institute (WIA) (IN)
- Cancer Research Center (US)
- Chongqing Cancer Hospital (CN)
- Université Laval (CA)
- University of Birmingham (GB)
Publication Details
- Journal
- Nucleic Acids Research
- Published
- 2024-10-24
- DOI
- https://doi.org/10.1093/nar/gkae918
- Citations
- 6
- Primary Topic
- DNA Repair Mechanisms
- Type
- article
- Field-Weighted Citation Impact
- 1.40
Funders
- University of Birmingham
- National Institutes of Health
- Canadian Institutes of Health Research
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill
- Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine