1. A small-molecule inhibitor of the BRCA2-RAD51 interaction modulates RAD51 assembly and potentiates DNA damage-induced cell death
- Author
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Chris Abell, Kalina T. Haas, Matthias T. Ehebauer, Luca Pellegrini, Amy Emery, May Marsh, David J. Huggins, Chiara R. Valenzano, Tom L. Blundell, Ashok R. Venkitaraman, Bryn Hardwick, Miyoung Lee, Lorraine Barber, Timothy Sharpe, Rajavel Srinivasan, John Skidmore, Nicola J. Francis-Newton, Alessandro Esposito, Duncan Scott, Claudio Dagostin, Marko Hyvönen, Gerhard Fischer, Andrew R. Bayly, Grahame J. McKenzie, Trevor Perrior, Tommaso Moschetti, Anthony G. Coyne, Scott, Duncan [0000-0003-1917-9576], Coyne, Anthony [0000-0003-0205-5630], Esposito, Alessandro [0000-0002-5051-091X], Pellegrini, Luca [0000-0002-9300-497X], Blundell, Tom [0000-0002-2708-8992], Skidmore, John [0000-0001-9108-7858], Abell, Chris [0000-0001-9174-1987], and Apollo - University of Cambridge Repository
- Subjects
Models, Molecular ,DNA repair ,DNA damage ,Poly ADP ribose polymerase ,Clinical Biochemistry ,genetic processes ,RAD51 ,Molecular Conformation ,homologous recombination ,Crystallography, X-Ray ,01 natural sciences ,Biochemistry ,Article ,law.invention ,Small Molecule Libraries ,chemistry.chemical_compound ,law ,Drug Discovery ,Tumor Cells, Cultured ,Humans ,structure-guided drug discovery ,Molecular Biology ,Polymerase ,Pharmacology ,BRCA2 Protein ,radiosensitizer ,biology ,Cell Death ,010405 organic chemistry ,BRCA2 ,protein-protein interaction inhibition ,0104 chemical sciences ,Cell biology ,enzymes and coenzymes (carbohydrates) ,chemistry ,biology.protein ,Recombinant DNA ,health occupations ,Molecular Medicine ,cancer therapy ,Rad51 Recombinase ,biological phenomena, cell phenomena, and immunity ,Homologous recombination ,RAD51 inhibitor ,DNA ,DNA Damage ,Protein Binding - Abstract
Summary BRCA2 controls RAD51 recombinase during homologous DNA recombination (HDR) through eight evolutionarily conserved BRC repeats, which individually engage RAD51 via the motif Phe-x-x-Ala. Using structure-guided molecular design, templated on a monomeric thermostable chimera between human RAD51 and archaeal RadA, we identify CAM833, a 529 Da orthosteric inhibitor of RAD51:BRC with a Kd of 366 nM. The quinoline of CAM833 occupies a hotspot, the Phe-binding pocket on RAD51 and the methyl of the substituted α-methylbenzyl group occupies the Ala-binding pocket. In cells, CAM833 diminishes formation of damage-induced RAD51 nuclear foci; inhibits RAD51 molecular clustering, suppressing extended RAD51 filament assembly; potentiates cytotoxicity by ionizing radiation, augmenting 4N cell-cycle arrest and apoptotic cell death and works with poly-ADP ribose polymerase (PARP)1 inhibitors to suppress growth in BRCA2-wildtype cells. Thus, chemical inhibition of the protein-protein interaction between BRCA2 and RAD51 disrupts HDR and potentiates DNA damage-induced cell death, with implications for cancer therapy., Graphical abstract, Highlights • CAM833 inhibits the protein-protein interaction between RAD51 and BRCA2 • Crystal structure shows CAM833 binds RAD51 at the same site as the BRCA2 FxxA motif • CAM833 blocks formation of RAD51 foci and filaments, preventing DNA repair • CAM833 potentiates cytotoxicity by IR and synergises with PARP1 inhibitors, Scott et al. describe CAM833, an inhibitor of DNA recombinase RAD51, that binds at the site normally occupied by the BRC repeats of the BRCA2 protein. Through blocking this protein-protein interaction, CAM833 is able to prevent RAD51-mediated homologous recombination and thus potentiate cancer cells to damage by radiation or PARP1 inhibition.
- Published
- 2021
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