bioRxiv preprint doi: https://doi.org/10.1101/2021.01.20.427433; this version posted January 20, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. Microarray screening reveals a non-conventional SUMO-binding mode linked to DNA repair by non-homologous end-joining Maria Jose Cabello-Lobato1, Matthew Jenner2,3, Christian M. Loch4, Stephen P. Jackson5, Qian Wu6, Matthew J. Cliff7, Christine K. Schmidt1* 1Manchester Cancer Research Centre (MCRC), Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, 555 Wilmslow Road, Manchester M20 4GJ, UK 2Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK 3Warwick Integrative Synthetic Biology (WISB) Centre, University of Warwick, Coventry, CV4 7AL, UK 4AVM Biomed, Pottstown, PA 19464, USA 5Wellcome/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge CB2 1QN, UK 6Astbury Centre for Structural Molecular Biology, School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK 7Manchester Institute of Biotechnology (MIB) and School of Chemistry, University of Manchester, Manchester M1 7DN, UK *Correspondence:
[email protected] SUMOylation is critical for a plethora of cellular signalling pathways including the repair of DNA double-strand breaks (DSBs). If misrepaired, DSBs can lead to cancer, neurodegeneration, immunodeficiency and premature ageing. Based on systematic proteome microarray screening combined with widely applicable carbene footprinting and high-resolution structural profiling, we define two non-conventional SUMO2- binding modules on XRCC4, a DNA repair protein important for DSB repair by non- homologous end-joining (NHEJ).