Monoubiquitination by the human Fanconi anemia core complex clamps FANCI:FANCD2 on DNA in filamentous arrays

eLife

Andrew Leis¹  Michael W Parker²  Sylvie van Twest³  Vincent J Murphy³  Michael Sharp³  Rohan Bythell-Douglas³  Andrew J Deans⁴  Wayne Crismani⁴  Winnie Tan⁴ 

[1] Bio21 Institute, University of Melbourne, Parkville, Australia;Bio21 Institute, University of Melbourne, Parkville, Australia;Structural Biology Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Australia;Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Australia;Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Australia;Department of Medicine (St. Vincent’s Health), The University of Melbourne, Melbourne, Australia;

关键词: Fanconi anemia;    DNA repair;    biochemistry;    ubiquitin;    Human;    Xenopus;   

DOI  :  10.7554/eLife.54128

来源: publisher

【 摘 要 】

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.

【 授权许可】

CC BY