biostudies-literatureElango RHoward Hughes Medical InstituteNCI NIH HHSNIGMS NIH HHS801-812https://www.ebi.ac.uk/biostudies/studies/S-EPMC9941964biostudies-literatureUnknown29(8)Vertebrate replication forks arrested at interstrand DNA cross-links (ICLs) engage the Fanconi anemia pathway to incise arrested forks, 'unhooking' the ICL and forming a double strand break (DSB) that is repaired by homologous recombination (HR). The FANCP product, SLX4, in complex with the XPF (also known as FANCQ or ERCC4)-ERCC1 endonuclease, mediates ICL unhooking. Whether this mechanism operates at replication fork barriers other than ICLs is unknown. Here, we study the role of mouse SLX4 in HR triggered by a site-specific chromosomal DNA-protein replication fork barrier formed by the Escherichia coli-derived Tus-Ter complex. We show that SLX4-XPF is required for Tus-Ter-induced HR but not for error-free HR induced by a replication-independent DSB. We additionally uncover a role for SLNature structural & molecular biologyThe structure-specific endonuclease complex SLX4-XPF regulates Tus-Ter-induced homologous recombination.PMC9941964R01 CA095175R01 GM134425R35 CA263813R01 CA204127Scully RLach FPWillis NANicholson KElango RSmogorzewska ADuffey EEPanday AfalseThe structure-specific endonuclease complex SLX4-XPF regulates Tus-Ter-induced homologous recombination.Vertebrate replication forks arrested at interstrand DNA cross-links (ICLs) engage the Fanconi anemia pathway to incise arrested forks, 'unhooking' the ICL and forming a double strand break (DSB) that is repaired by homologous recombination (HR). The FANCP product, SLX4, in complex with the XPF (also known as FANCQ or ERCC4)-ERCC1 endonuclease, mediates ICL unhooking. Whether this mechanism operates at replication fork barriers other than ICLs is unknown. Here, we study the role of mouse SLX4 in HR triggered by a site-specific chromosomal DNA-protein replication fork barrier formed by the Escherichia coli-derived Tus-Ter complex. We show that SLX4-XPF is required for Tus-Ter-induced HR but not for error-free HR induced by a replication-independent DSB. We additionally uncover a role for SL2022-01-01T00:00:00Z2022 Aug2025-04-22T09:57:37.397Z2025-02-18T22:57:22.047ZS-EPMC99419643594138010.1038/s41594-022-00812-9