NEIL3 Promotes DSB Repair in Fanconi Anemia/BRCA Pathway via Homologous Recombination

Abstract

Summary Interstrand crosslinks (ICLs) repair by the canonical Fanconi anemia (FA) pathway generates double-strand breaks (DSBs), which are subsequently repaired by the homologous recombination (HR) pathway. Recent studies show that the NEIL3 DNA glycosylase repairs psoralen-ICLs by direct unhooking. However, whether and how NEIL3 regulates MMC and cisplatin-ICL repair remains unclear. Here we show that NEIL3 participates in DSB repair step of ICL repair by promoting HR pathway. Mechanistically, NEIL3 is recruited to the DSB sites through its GRF zinc finger motifs. NEIL3 interacts with the DSB resection machinery, including CtIP, the MRE11-RAD50-NBS1 (MRN) complex, and DNA2, which is mediated by the GRF zinc finger motifs. In addition, NEIL3 is necessary for the chromatin recruitment of the resection machinery, and depletion of NEIL3 decreases end resection and compromises HR. Taken together, our results show that NEIL3 plays an important role in MMC/cisplatin-ICL repair by promoting the HR step in FA/BRCA pathway.