Specificity for deubiquitination of monoubiquitinated FANCD2 is driven by the N-terminus of USP1

Arkinson, C., Chaugule, V. K., Toth, R. and Walden, H. (2018) Specificity for deubiquitination of monoubiquitinated FANCD2 is driven by the N-terminus of USP1. Life Science Alliance, 1(5), e201800162. (doi: 10.26508/lsa.201800162) (PMID:30456385) (PMCID:PMC6238601)

Abstract

The Fanconi anemia pathway for DNA interstrand crosslink repair and the translesion synthesis pathway for DNA damage tolerance both require cycles of monoubiquitination and deubiquitination. The ubiquitin-specific protease-1 (USP1), in complex with USP1-associated factor 1, regulates multiple DNA repair pathways by deubiquitinating monoubiquitinated Fanconi anemia group D2 protein (FANCD2), Fanconi anemia group I protein (FANCI), and proliferating cell nuclear antigen (PCNA). Loss of USP1 activity gives rise to chromosomal instability. Whereas many USPs hydrolyse ubiquitin–ubiquitin linkages, USP1 targets ubiquitin–substrate conjugates at specific sites. The molecular basis of USP1's specificity for multiple substrates is poorly understood. Here, we reconstitute deubiquitination of purified monoubiquitinated FANCD2, FANCI, and PCNA and show that molecular determinants for substrate deubiquitination by USP1 reside within the highly conserved and extended N-terminus. We found that the N-terminus of USP1 harbours a FANCD2-specific binding sequence required for deubiquitination of K561 on FANCD2. In contrast, the N-terminus is not required for direct PCNA or FANCI deubiquitination. Furthermore, we show that the N-terminus of USP1 is sufficient to engineer specificity in a more promiscuous USP.

• Item Type: Articles
• Additional Information: This work was supported by the Medical Research Council (grant MC_UU_12016/12); the European Molecular Biology Organization Young Investigator Programme to H Walden; and the European Research Council consolidator grant (ERC-2015-CoG-681582 ICLUb) to H Walden.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Chaugule, Dr Viduth and Arkinson, Connor and Walden, Professor Helen
• Authors: Arkinson, C., Chaugule, V. K., Toth, R., and Walden, H.
• College/School: College of Medical Veterinary and Life Sciences; College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Life Science Alliance
• Publisher: Life Science Alliance
• ISSN: 2575-1077
• ISSN (Online): 2575-1077
• Copyright Holders: Copyright © 2018 The Authors
• First Published: First published in Life Science Alliance 1(5):e201800162
• Publisher Policy: Reproduced under a Creative Commons License