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Rennie ML, Gundogdu M, Arkinson C, Liness S, Frame S, Walden H. Structural and Biochemical Insights into the Mechanism of Action of the Clinical USP1 Inhibitor, KSQ-4279. J Med Chem 2024; 67:15557-15568. [PMID: 39190802 PMCID: PMC11403619 DOI: 10.1021/acs.jmedchem.4c01184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2024]
Abstract
DNA damage triggers cell signaling cascades that mediate repair. This signaling is frequently dysregulated in cancers. The proteins that mediate this signaling are potential targets for therapeutic intervention. Ubiquitin-specific protease 1 (USP1) is one such target, with small-molecule inhibitors already in clinical trials. Here, we use biochemical assays and cryo-electron microscopy (cryo-EM) to study the clinical USP1 inhibitor, KSQ-4279 (RO7623066), and compare this to the well-established tool compound, ML323. We find that KSQ-4279 binds to the same cryptic site of USP1 as ML323 but disrupts the protein structure in subtly different ways. Inhibitor binding drives a substantial increase in thermal stability of USP1, which may be mediated through the inhibitors filling a hydrophobic tunnel-like pocket in USP1. Our results contribute to the understanding of the mechanism of action of USP1 inhibitors at the molecular level.
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Affiliation(s)
- Martin Luke Rennie
- School of Molecular Biosciences, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Mehmet Gundogdu
- Ubiquigent Ltd, Dundee University Incubator, James Lindsay Place, Dundee DD1 5JJ, U.K
| | - Connor Arkinson
- School of Molecular Biosciences, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Steven Liness
- Ubiquigent Ltd, Dundee University Incubator, James Lindsay Place, Dundee DD1 5JJ, U.K
| | - Sheelagh Frame
- Ubiquigent Ltd, Dundee University Incubator, James Lindsay Place, Dundee DD1 5JJ, U.K
| | - Helen Walden
- School of Molecular Biosciences, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K
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2
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Alcón P, Kaczmarczyk AP, Ray KK, Liolios T, Guilbaud G, Sijacki T, Shen Y, McLaughlin SH, Sale JE, Knipscheer P, Rueda DS, Passmore LA. FANCD2-FANCI surveys DNA and recognizes double- to single-stranded junctions. Nature 2024; 632:1165-1173. [PMID: 39085614 PMCID: PMC11358013 DOI: 10.1038/s41586-024-07770-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 07/01/2024] [Indexed: 08/02/2024]
Abstract
DNA crosslinks block DNA replication and are repaired by the Fanconi anaemia pathway. The FANCD2-FANCI (D2-I) protein complex is central to this process as it initiates repair by coordinating DNA incisions around the lesion1. However, D2-I is also known to have a more general role in DNA repair and in protecting stalled replication forks from unscheduled degradation2-4. At present, it is unclear how DNA crosslinks are recognized and how D2-I functions in replication fork protection. Here, using single-molecule imaging, we show that D2-I is a sliding clamp that binds to and diffuses on double-stranded DNA. Notably, sliding D2-I stalls on encountering single-stranded-double-stranded (ss-ds) DNA junctions, structures that are generated when replication forks stall at DNA lesions5. Using cryogenic electron microscopy, we determined structures of D2-I on DNA that show that stalled D2-I makes specific interactions with the ss-dsDNA junction that are distinct from those made by sliding D2-I. Thus, D2-I surveys dsDNA and, when it reaches an ssDNA gap, it specifically clamps onto ss-dsDNA junctions. Because ss-dsDNA junctions are found at stalled replication forks, D2-I can identify sites of DNA damage. Therefore, our data provide a unified molecular mechanism that reconciles the roles of D2-I in the recognition and protection of stalled replication forks in several DNA repair pathways.
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Affiliation(s)
- Pablo Alcón
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Artur P Kaczmarczyk
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK
- MRC Laboratory of Medical Sciences, London, UK
| | - Korak Kumar Ray
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK
- MRC Laboratory of Medical Sciences, London, UK
| | - Themistoklis Liolios
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | | | | | - Yichao Shen
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | | | - Puck Knipscheer
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - David S Rueda
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK.
- MRC Laboratory of Medical Sciences, London, UK.
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3
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Rennie ML, Arkinson C, Chaugule VK, Walden H. Cryo-EM reveals a mechanism of USP1 inhibition through a cryptic binding site. SCIENCE ADVANCES 2022; 8:eabq6353. [PMID: 36170365 PMCID: PMC9519042 DOI: 10.1126/sciadv.abq6353] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/10/2022] [Indexed: 06/16/2023]
Abstract
Repair of DNA damage is critical to genomic integrity and frequently disrupted in cancers. Ubiquitin-specific protease 1 (USP1), a nucleus-localized deubiquitinase, lies at the interface of multiple DNA repair pathways and is a promising drug target for certain cancers. Although multiple inhibitors of this enzyme, including one in phase 1 clinical trials, have been established, their binding mode is unknown. Here, we use cryo-electron microscopy to study an assembled enzyme-substrate-inhibitor complex of USP1 and the well-established inhibitor, ML323. Achieving 2.5-Å resolution, with and without ML323, we find an unusual binding mode in which the inhibitor disrupts part of the hydrophobic core of USP1. The consequent conformational changes in the secondary structure lead to subtle rearrangements in the active site that underlie the mechanism of inhibition. These structures provide a platform for structure-based drug design targeting USP1.
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Affiliation(s)
- Martin L. Rennie
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Connor Arkinson
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Viduth K. Chaugule
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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4
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Sijacki T, Alcón P, Chen ZA, McLaughlin SH, Shakeel S, Rappsilber J, Passmore LA. The DNA-damage kinase ATR activates the FANCD2-FANCI clamp by priming it for ubiquitination. Nat Struct Mol Biol 2022; 29:881-890. [PMID: 36050501 PMCID: PMC7613635 DOI: 10.1038/s41594-022-00820-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 07/18/2022] [Indexed: 01/10/2023]
Abstract
DNA interstrand cross-links are tumor-inducing lesions that block DNA replication and transcription. When cross-links are detected at stalled replication forks, ATR kinase phosphorylates FANCI, which stimulates monoubiquitination of the FANCD2-FANCI clamp by the Fanconi anemia core complex. Monoubiquitinated FANCD2-FANCI is locked onto DNA and recruits nucleases that mediate DNA repair. However, it remains unclear how phosphorylation activates this pathway. Here, we report structures of FANCD2-FANCI complexes containing phosphomimetic FANCI. We observe that, unlike wild-type FANCD2-FANCI, the phosphomimetic complex closes around DNA, independent of the Fanconi anemia core complex. The phosphomimetic mutations do not substantially alter DNA binding but instead destabilize the open state of FANCD2-FANCI and alter its conformational dynamics. Overall, our results demonstrate that phosphorylation primes the FANCD2-FANCI clamp for ubiquitination, showing how multiple posttranslational modifications are coordinated to control DNA repair.
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Affiliation(s)
| | - Pablo Alcón
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Zhuo A Chen
- Technische Universität Berlin, Chair of Bioanalytics, Berlin, Germany
| | | | - Shabih Shakeel
- MRC Laboratory of Molecular Biology, Cambridge, UK
- Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Juri Rappsilber
- Technische Universität Berlin, Chair of Bioanalytics, Berlin, Germany
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5
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Foster B, Attwood M, Gibbs-Seymour I. Tools for Decoding Ubiquitin Signaling in DNA Repair. Front Cell Dev Biol 2021; 9:760226. [PMID: 34950659 PMCID: PMC8690248 DOI: 10.3389/fcell.2021.760226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/09/2021] [Indexed: 12/21/2022] Open
Abstract
The maintenance of genome stability requires dedicated DNA repair processes and pathways that are essential for the faithful duplication and propagation of chromosomes. These DNA repair mechanisms counteract the potentially deleterious impact of the frequent genotoxic challenges faced by cells from both exogenous and endogenous agents. Intrinsic to these mechanisms, cells have an arsenal of protein factors that can be utilised to promote repair processes in response to DNA lesions. Orchestration of the protein factors within the various cellular DNA repair pathways is performed, in part, by post-translational modifications, such as phosphorylation, ubiquitin, SUMO and other ubiquitin-like modifiers (UBLs). In this review, we firstly explore recent advances in the tools for identifying factors involved in both DNA repair and ubiquitin signaling pathways. We then expand on this by evaluating the growing repertoire of proteomic, biochemical and structural techniques available to further understand the mechanistic basis by which these complex modifications regulate DNA repair. Together, we provide a snapshot of the range of methods now available to investigate and decode how ubiquitin signaling can promote DNA repair and maintain genome stability in mammalian cells.
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Affiliation(s)
| | | | - Ian Gibbs-Seymour
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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6
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Mondal S, Reddy S, Mukhopadhyay SS. Optimized structure of monoubiquitinated FANCD2 (human) at Lys 561: a theoretical approach. J Biomol Struct Dyn 2021; 40:9374-9388. [PMID: 34014148 DOI: 10.1080/07391102.2021.1929490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fanconi anaemia pathway repairs inter-strand cross linking damage (ICL) of the DNA. Monoubiquitination of FANCD2 and FANCI is very crucial for ICL repairing. In this work we have tried to understand the monoubiquitinated FANCD2 structure, which facilitates the FANCD2 for binding the damage part of the chromatin. Crystal structure of the monoubiquitinated FANCD2 alone is not available, therefore we have modelled the optimized structure of the human monoubiquitinated (Lys 561) FANCD2. As there is no suitable software or web server we have developed a method for building up monoubiquitinated product and validated on simplest monoubiquitinated protein, diubiquitin. We have predicted the structure of human monoubiquitinated FANCD2 by using our method and studied the interaction with DNA by docking studies. Molecular Dynamics (MD) simulation has been used to understand the stability of the structure. Large structural differences have been observed between FANCD2 and monoubiquitinated FANCD2. Docking studies with DNA suggest that the binding site varies for the FANCD2 and monoubiquitinated FANCD2.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sudipa Mondal
- Department of Biotechnology, National Institute of Technology, Durgapur, India
| | - Subba Reddy
- Department of Biotechnology, National Institute of Technology, Durgapur, India
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7
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Structural basis of FANCD2 deubiquitination by USP1-UAF1. Nat Struct Mol Biol 2021; 28:356-364. [PMID: 33795880 DOI: 10.1038/s41594-021-00576-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/22/2021] [Indexed: 12/19/2022]
Abstract
Ubiquitin-specific protease 1 (USP1) acts together with the cofactor UAF1 during DNA repair processes to specifically remove monoubiquitin signals. One substrate of the USP1-UAF1 complex is the monoubiquitinated FANCI-FANCD2 heterodimer, which is involved in the repair of DNA interstrand crosslinks via the Fanconi anemia pathway. Here we determine structures of human USP1-UAF1 with and without ubiquitin and bound to monoubiquitinated FANCI-FANCD2. The crystal structures of USP1-UAF1 reveal plasticity in USP1 and key differences to USP12-UAF1 and USP46-UAF1, two related proteases. A cryo-EM reconstruction of USP1-UAF1 in complex with monoubiquitinated FANCI-FANCD2 highlights a highly orchestrated deubiquitination process, with USP1-UAF1 driving conformational changes in the substrate. An extensive interface between UAF1 and FANCI, confirmed by mutagenesis and biochemical assays, provides a molecular explanation for the requirement of both proteins, despite neither being directly involved in catalysis. Overall, our data provide molecular details of USP1-UAF1 regulation and substrate recognition.
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8
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Rennie ML, Lemonidis K, Arkinson C, Chaugule VK, Clarke M, Streetley J, Spagnolo L, Walden H. Differential functions of FANCI and FANCD2 ubiquitination stabilize ID2 complex on DNA. EMBO Rep 2020; 21:e50133. [PMID: 32510829 PMCID: PMC7332966 DOI: 10.15252/embr.202050133] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/15/2020] [Accepted: 05/15/2020] [Indexed: 12/24/2022] Open
Abstract
The Fanconi anaemia (FA) pathway is a dedicated pathway for the repair of DNA interstrand crosslinks and is additionally activated in response to other forms of replication stress. A key step in the FA pathway is the monoubiquitination of each of the two subunits (FANCI and FANCD2) of the ID2 complex on specific lysine residues. However, the molecular function of these modifications has been unknown for nearly two decades. Here, we find that ubiquitination of FANCD2 acts to increase ID2's affinity for double‐stranded DNA via promoting a large‐scale conformational change in the complex. The resulting complex encircles DNA, by forming a secondary “Arm” ID2 interface. Ubiquitination of FANCI, on the other hand, largely protects the ubiquitin on FANCD2 from USP1‐UAF1 deubiquitination, with key hydrophobic residues of FANCI's ubiquitin being important for this protection. In effect, both of these post‐translational modifications function to stabilize a conformation in which the ID2 complex encircles DNA.
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Affiliation(s)
- Martin L Rennie
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Kimon Lemonidis
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Connor Arkinson
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Viduth K Chaugule
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Mairi Clarke
- Scottish Centre for Macromolecular Imaging, University of Glasgow, Glasgow, UK
| | - James Streetley
- Scottish Centre for Macromolecular Imaging, University of Glasgow, Glasgow, UK
| | - Laura Spagnolo
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Helen Walden
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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9
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Alcón P, Shakeel S, Chen ZA, Rappsilber J, Patel KJ, Passmore LA. FANCD2-FANCI is a clamp stabilized on DNA by monoubiquitination of FANCD2 during DNA repair. Nat Struct Mol Biol 2020; 27:240-248. [PMID: 32066963 PMCID: PMC7067600 DOI: 10.1038/s41594-020-0380-1] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 01/14/2020] [Indexed: 01/18/2023]
Abstract
Vertebrate DNA crosslink repair excises toxic replication-blocking DNA crosslinks. Numerous factors involved in crosslink repair have been identified, and mutations in their corresponding genes cause Fanconi anemia (FA). A key step in crosslink repair is monoubiquitination of the FANCD2-FANCI heterodimer, which then recruits nucleases to remove the DNA lesion. Here, we use cryo-EM to determine the structures of recombinant chicken FANCD2 and FANCI complexes. FANCD2-FANCI adopts a closed conformation when the FANCD2 subunit is monoubiquitinated, creating a channel that encloses double-stranded DNA (dsDNA). Ubiquitin is positioned at the interface of FANCD2 and FANCI, where it acts as a covalent molecular pin to trap the complex on DNA. In contrast, isolated FANCD2 is a homodimer that is unable to bind DNA, suggestive of an autoinhibitory mechanism that prevents premature activation. Together, our work suggests that FANCD2-FANCI is a clamp that is locked onto DNA by ubiquitin, with distinct interfaces that may recruit other DNA repair factors.
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Affiliation(s)
- Pablo Alcón
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | - Zhuo A Chen
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Juri Rappsilber
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
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10
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Tan W, Murphy VJ, Charron A, van Twest S, Sharp M, Constantinou A, Parker MW, Crismani W, Bythell-Douglas R, Deans AJ. Preparation and purification of mono-ubiquitinated proteins using Avi-tagged ubiquitin. PLoS One 2020; 15:e0229000. [PMID: 32092106 PMCID: PMC7039436 DOI: 10.1371/journal.pone.0229000] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 01/27/2020] [Indexed: 01/13/2023] Open
Abstract
Site-specific conjugation of ubiquitin onto a range of DNA repair proteins regulates their critical functions in the DNA damage response. Biochemical and structural characterization of these functions are limited by an absence of tools for the purification of DNA repair proteins in purely the ubiquitinated form. To overcome this barrier, we designed a ubiquitin fusion protein that is N-terminally biotinylated and can be conjugated by E3 RING ligases onto various substrates. Biotin affinity purification of modified proteins, followed by cleavage of the affinity tag leads to release of natively-mono-ubiquitinated substrates. As proof-of-principle, we applied this method to several substrates of mono-ubiquitination in the Fanconi anemia (FA)-BRCA pathway of DNA interstrand crosslink repair. These include the FANCI:FANCD2 complex, the PCNA trimer and BRCA1 modified nucleosomes. This method provides a simple approach to study the role of mono-ubiquitination in DNA repair or any other mono-ubiquitination signaling pathways.
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Affiliation(s)
- Winnie Tan
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Medicine (St. Vincent’s Health), The University of Melbourne, Victoria, Australia
| | - Vincent J. Murphy
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Aude Charron
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- National Graduate School of Chemistry of Montpellier (ENSCM), Montpellier, France
| | - Sylvie van Twest
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Michael Sharp
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Angelos Constantinou
- Institute of Human Genetics (IGH), Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM), Montpellier, France
| | - Michael W. Parker
- Structural Biology Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Bio21 Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Wayne Crismani
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Medicine (St. Vincent’s Health), The University of Melbourne, Victoria, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Medicine (St. Vincent’s Health), The University of Melbourne, Victoria, Australia
| | - Andrew J. Deans
- Genome Stability Unit, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Medicine (St. Vincent’s Health), The University of Melbourne, Victoria, Australia
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11
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Chaugule VK, Arkinson C, Rennie ML, Kämäräinen O, Toth R, Walden H. Allosteric mechanism for site-specific ubiquitination of FANCD2. Nat Chem Biol 2019; 16:291-301. [PMID: 31873223 PMCID: PMC7035956 DOI: 10.1038/s41589-019-0426-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 11/05/2019] [Indexed: 01/31/2023]
Abstract
DNA damage repair is implemented by proteins that are coordinated by specialised molecular signals. One such signal in the Fanconi Anemia (FA) DNA-interstrand crosslink repair pathway is the site-specific monoubiquitination of FANCD2 and FANCI. The signal is mediated by a multi-protein FA core complex (FA-CC) however, the mechanics for precise ubiquitination remain elusive. We show that FANCL, the RING-bearing module in FA-CC, allosterically activates its cognate E2 Ube2T to drive site-specific FANCD2 ubiquitination. Unlike typical RING E3 ligases, FANCL catalyses ubiquitination by rewiring Ube2T’s intra-residue network to influence the active site. Consequently, a basic triad unique to Ube2T engages a structured acidic patch near the target lysine on FANCD2. This three-dimensional complementarity, between the E2 active site and substrate surface, induced by FANCL is central to site-specific monoubiquitination in the FA pathway. Furthermore, the allosteric network of Ube2T can be engineered to enhance FANCL catalysed FANCD2-FANCI di-monoubiquitination without compromising site-specificity.
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Affiliation(s)
- Viduth K Chaugule
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK. .,MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK.
| | - Connor Arkinson
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.,MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK
| | - Martin L Rennie
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Outi Kämäräinen
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Rachel Toth
- MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK
| | - Helen Walden
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK. .,MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee, UK.
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