Journal article

The FA Core Complex Contains a Homo-dimeric Catalytic Module for the Symmetric Mono-ubiquitination of FANCI-FANCD2

Paolo Swuec, Ludovic Renault, Aaron Borg, Fenil Shah, Vincent J Murphy, Sylvie van Twest, Ambrosius P Snijders, Andrew J Deans, Alessandro Costa

CELL REPORTS | CELL PRESS | Published : 2017

Abstract

Activation of the main DNA interstrand crosslink repair pathway in higher eukaryotes requires mono-ubiquitination of FANCI and FANCD2 by FANCL, the E3 ligase subunit of the Fanconi anemia core complex. FANCI and FANCD2 form a stable complex; however, the molecular basis of their ubiquitination is ill defined. FANCD2 mono-ubiquitination by FANCL is stimulated by the presence of the FANCB and FAAP100 core complex components, through an unknown mechanism. How FANCI mono-ubiquitination is achieved remains unclear. Here, we use structural electron microscopy, combined with crosslink-coupled mass spectrometry, to find that FANCB, FANCL, and FAAP100 form a dimer of trimers, containing two FANCL mol..

View full abstract

Grants

Awarded by The Francis Crick Institute


Awarded by National Breast Cancer Foundation


Funding Acknowledgements

We would like to thank J. Gannon, A. Davies, and Cell Services at The Francis Crick Institute for help with the baculovirus work; and R. Carzaniga, L. Collinson, and K. MacLellan-Gibson for technical support with EM. We acknowledge Diamond for access and support of the cryo-EM facilities at eBIC, proposal EM14266, funded by Wellcome Trust/MRC/BBSRC. We thank A. Siebert, D. Clare, and S. Welsch for help with the Titan Krios. A.J.D. is funded by the National Breast Cancer Foundation (Australia), the Victorian Cancer Agency, the Fanconi Anemia Research Fund, the Victorian Government's OIS Program, and the Cancer Council of Victoria. Research in the A.C. lab is supported by The Francis Crick Institute (which receives its core funding from Cancer Research UK, the UK Medical Research Council, and the Wellcome Trust).