Structure-Based Optimization of Covalent, Small-Molecule Stabilizers of the 14-3-3 sigma /ER alpha Protein-Protein Interaction from Nonselective Fragments.Konstantinidou, M., Visser, E.J., Vandenboorn, E., Chen, S., Jaishankar, P., Overmans, M., Dutta, S., Neitz, R.J., Renslo, A.R., Ottmann, C., Brunsveld, L., Arkin, M.R.
(2023) J Am Chem Soc 145: 20328-20343
- PubMed: 37676236
- DOI: https://doi.org/10.1021/jacs.3c05161
- Primary Citation of Related Structures:
8AI0, 8ALR, 8ALT, 8ALV, 8ALW, 8AM7, 8ANF, 8AOY, 8APS, 8AQ1, 8AQC, 8AQE, 8AQZ, 8AR4, 8AR5, 8ARG, 8ARO, 8ARQ, 8ARR, 8ARW, 8ARX, 8ARY, 8ARZ, 8AS1, 8AT9, 8ATP, 8ATR, 8ATS, 8AU2, 8AUS, 8AUY, 8AV3, 8AV4, 8AV7, 8AV8, 8AWG, 8AXE, 8AXU, 8AZE, 8B39
- PubMed Abstract:
The stabilization of protein-protein interactions (PPIs) has emerged as a promising strategy in chemical biology and drug discovery. The identification of suitable starting points for stabilizing native PPIs and their subsequent elaboration into selective and potent molecular glues lacks structure-guided optimization strategies. We have previously identified a disulfide fragment that stabilized the hub protein 14-3-3σ bound to several of its clients, including ERα and C-RAF. Here, we show the structure-based optimization of the nonselective fragment toward selective and highly potent small-molecule stabilizers of the 14-3-3σ/ERα complex. The more elaborated molecular glues, for example, show no stabilization of 14-3-3σ/C-RAF up to 150 μM compound. Orthogonal biophysical assays, including mass spectrometry and fluorescence anisotropy, were used to establish structure-activity relationships. The binding modes of 37 compounds were elucidated with X-ray crystallography, which further assisted the concomitant structure-guided optimization. By targeting specific amino acids in the 14-3-3σ/ERα interface and locking the conformation with a spirocycle, the optimized covalent stabilizer 181 achieved potency, cooperativity, and selectivity similar to the natural product Fusicoccin-A. This case study showcases the value of addressing the structure, kinetics, and cooperativity for molecular glue development.
Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.