TY - JOUR TI - Monoubiquitination by the human Fanconi anemia core complex clamps FANCI:FANCD2 on DNA in filamentous arrays AU - Tan, Winnie AU - van Twest, Sylvie AU - Leis, Andrew AU - Bythell-Douglas, Rohan AU - Murphy, Vincent J AU - Sharp, Michael AU - Parker, Michael W AU - Crismani, Wayne AU - Deans, Andrew J A2 - Heyer, Wolf-Dietrich A2 - Kuriyan, John VL - 9 PY - 2020 DA - 2020/03/13 SP - e54128 C1 - eLife 2020;9:e54128 DO - 10.7554/eLife.54128 UR - https://doi.org/10.7554/eLife.54128 AB - FANCI:FANCD2 monoubiquitination is a critical event for replication fork stabilization by the Fanconi anemia (FA) DNA repair pathway. It has been proposed that at stalled replication forks, monoubiquitinated-FANCD2 serves to recruit DNA repair proteins that contain ubiquitin-binding motifs. Here, we have reconstituted the FA pathway in vitro to study functional consequences of FANCI:FANCD2 monoubiquitination. We report that monoubiquitination does not promote any specific exogenous protein:protein interactions, but instead stabilizes FANCI:FANCD2 heterodimers on dsDNA. This clamping requires monoubiquitination of only the FANCD2 subunit. We further show using electron microscopy that purified monoubiquitinated FANCI:FANCD2 forms filament-like arrays on long dsDNA. Our results reveal how monoubiquitinated FANCI:FANCD2, defective in many cancer types and all cases of FA, is activated upon DNA binding. KW - Fanconi anemia KW - DNA repair KW - biochemistry KW - ubiquitin JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -